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  • Blackwell Publishing Ltd
  • Annual Reviews
  • 2005-2009  (3.882)
  • 1990-1994
  • 1980-1984
  • 2007  (550)
  • 2005  (3.332)
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  • 2005-2009  (3.882)
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  • 1
    Publikationsdatum: 2022-05-25
    Beschreibung: Author Posting. © Annual Reviews, 2003. This article is posted here by permission of Annual Reviews for personal use, not for redistribution. The definitive version was published in Annual Review of Environment and Resources 28 (2003): 521-558, doi:10.1146/annurev.energy.28.011503.163443.
    Beschreibung: Agriculture and industrial development have led to inadvertent changes in the natural carbon cycle. As a consequence, concentrations of carbon dioxide and other greenhouse gases have increased in the atmosphere and may lead to changes in climate. The current challenge facing society is to develop options for future management of the carbon cycle. A variety of approaches has been suggested: direct reduction of emissions, deliberate manipulation of the natural carbon cycle to enhance sequestration, and capture and isolation of carbon from fossil fuel use. Policy development to date has laid out some of the general principles to which carbon management should adhere. These are summarized as: how much carbon is stored, by what means, and for how long. To successfully manage carbon for climate purposes requires increased understanding of carbon cycle dynamics and improvement in the scientific capabilities available for measurement as well as for policy needs. The specific needs for scientific information to underpin carbon cycle management decisions are not yet broadly known. A stronger dialogue between decision makers and scientists must be developed to foster improved application of scientific knowledge to decisions. This review focuses on the current knowledge of the carbon cycle, carbon measurement capabilities (with an emphasis on the continental scale) and the relevance of carbon cycle science to carbon sequestration goals.
    Beschreibung: The National Center for Atmospheric Research is supported by the National Science Foundation.
    Schlagwort(e): Carbon sequestration ; Measurement techniques ; Climate ; Kyoto protocol
    Repository-Name: Woods Hole Open Access Server
    Materialart: Article
    Format: 406392 bytes
    Format: application/pdf
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  • 2
    Publikationsdatum: 2022-05-25
    Beschreibung: First published online as a Review in Advance on October 24, 2005. (Some corrections may occur before final publication online and in print)
    Beschreibung: Author Posting. © Annual Reviews, 2005. This article is posted here by permission of Annual Reviews for personal use, not for redistribution. The definitive version was published in Annual Review of Physiology 68 (2006): 22.1-22.29, doi:10.1146/annurev.physiol.68.040104.105418.
    Beschreibung: Superfast muscles of vertebrates power sound production. The fastest, the swimbladder muscle of toadfish, generates mechanical power at frequencies in excess of 200 Hz. To operate at these frequencies, the speed of relaxation has had to increase approximately 50-fold. This increase is accomplished by modifications of three kinetic traits: (a) a fast calcium transient due to extremely high concentration of sarcoplasmic reticulum (SR)-Ca2+ pumps and parvalbumin, (b) fast off-rate of Ca2+ from troponin C due to an alteration in troponin, and (c) fast cross-bridge detachment rate constant (g, 50 times faster than that in rabbit fast-twitch muscle) due to an alteration in myosin. Although these three modifications permit swimbladder muscle to generate mechanical work at high frequencies (where locomotor muscles cannot), it comes with a cost: The high g causes a large reduction in attached force-generating cross-bridges, making the swimbladder incapable of powering low-frequency locomotory movements. Hence the locomotory and sound-producing muscles have mutually exclusive designs.
    Beschreibung: This work was made possible by support from NIH grants AR38404 and AR46125 as well as the University of Pennsylvania Research Foundation.
    Schlagwort(e): Parvalbumin ; Ca2+ release ; Ca2+ uptake ; Cross-bridges ; Adaptation ; Sound production ; Whitman Center
    Repository-Name: Woods Hole Open Access Server
    Materialart: Article
    Format: 567086 bytes
    Format: application/pdf
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  • 3
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 161-196 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Our views regarding the origins and functions of splenic marginal zone B cells have changed considerably over the past few years. Perspectives regarding the development and function of these cells vary considerably between investigators studying human and rodent immunology. Marginal zone B cells are now recognized to constitute a distinct naive B lymphoid lineage. Considerable progress has been made regarding the mechanisms involved in marginal zone B cell development in the mouse. Many of the molecular events that participate in the retention of this lineage of B cells in the marginal zone have been identified. Here, we discuss the functions of these cells in both innate and adaptive immunity. We also attempt to reconcile differing viewpoints regarding the generation and function of marginal zone B cells in rodents and primates.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 487-513 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Helper T (Th) cellĐ??regulated B cell immunity progresses in an ordered cascade of cellular development that culminates in the production of antigen-specific memory B cells. The recognition of peptide MHC class II complexes on activated antigen-presenting cells is critical for effective Th cell selection, clonal expansion, and effector Th cell function development (Phase I). Cognate effector Th cellĐ??B cell interactions then promote the development of either short-lived plasma cells (PCs) or germinal centers (GCs) (Phase II). These GCs expand, diversify, and select high-affinity variants of antigen-specific B cells for entry into the long-lived memory B cell compartment (Phase III). Upon antigen rechallenge, memory B cells rapidly expand and differentiate into PCs under the cognate control of memory Th cells (Phase IV). We review the cellular and molecular regulators of this dynamic process with emphasis on the multiple memory B cell fates that develop in vivo.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 415-445 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The proliferation and differentiation of lymphocytes are regulated by receptors localized on the cell surface. Engagement of these receptors induces the activation of intracellular signaling proteins that transmit the receptor signals to distinct targets and control the cellular responses. The first signaling proteins to be discovered in higher organisms were the products of oncogenes. For example, the kinases Src and Abelson (Abl) were originally identified as oncogenes and were later characterized as important proteins for signal transduction in various cell types, including lymphocytes. Now, as many cellular signaling molecules have been discovered and ordered into certain pathways, we can better understand why particular signaling proteins are associated with tumorigenesis. In this review, we discuss recent progress in unraveling the molecular mechanisms of signaling pathways that control the proliferation and differentiation of early B cells. We point out the concepts of auto-inhibition and subcellular localization as crucial aspects in the regulation of B cell signaling.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 683-747 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Multiple sclerosis (MS) develops in young adults with a complex predisposing genetic trait and probably requires an inciting environmental insult such as a viral infection to trigger the disease. The activation of CD4+ autoreactive T cells and their differentiation into a Th1 phenotype are a crucial events in the initial steps, and these cells are probably also important players in the long-term evolution of the disease. Damage of the target tissue, the central nervous system, is, however, most likely mediated by other components of the immune system, such as antibodies, complement, CD8+ T cells, and factors produced by innate immune cells. Perturbations in immunomodulatory networks that include Th2 cells, regulatory CD4+ T cells, NK cells, and others may in part be responsible for the relapsing-remitting or chronic progressive nature of the disease. However, an important paradigmatic shift in the study of MS has occurred in the past decade. It is now clear that MS is not just a disease of the immune system, but that factors contributed by the central nervous system are equally important and must be considered in the future.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 651-682 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: CD8+ T cells play a critical role in antiviral immunity by exerting direct antiviral activity against infected cells. Because of their ability to recognize all types of viral proteins, they offer the promise of providing broad immunity to viruses that evade humoral immunity by varying their surface proteins. Consequently, there is considerable interest in developing vaccines that elicit effective antiviral TCD8+ responses. Generating optimal vaccines ultimately requires rational design based on detailed knowledge of how TCD8+ are activated in vivo under natural circumstances. Here we review recent progress obtained largely by in vivo studies in mice to understand the mechanistic basis for activation of naive TCD8+ in virus infections. These studies point the way to detailed understanding and provide some key information for vaccine development, although much remains to be learned to enable truly rational vaccine design.
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 945-974 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The Notch pathway is gaining increasing recognition as a key regulator of developmental choices, differentiation, and function throughout the hematolymphoid system. Notch controls the generation of hematopoietic stem cells during embryonic development and may affect their subsequent homeostasis. Commitment to the T??cell lineage and subsequent stages of early thymopoiesis is critically regulated by Notch. Recent data indicate that Notch can also direct the differentiation and activity of peripheral T and B cells. Thus, the full spectrum of Notch effects is just beginning to be understood. In this review, we discuss this explosion of knowledge as well as current controversies and challenges in the field.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: High-performing project teams are crucial for effective research and development (R&D). To become high performing, teams need to make use of their different skills and reflect upon their collective actions, thereby combining knowledge that could lead to value-adding activities for the company. This article describes the use of team coaching in supporting team reflection and learning in global R&D project teams. A collaborative research approach was used during the 8 months of coaching, with several inquiry methods being employed. The results indicate that coaching interventions have a positive effect on team performance, both from an efficiency perspective as well as from a creativity and climate perspective. Practical and theoretical implications are discussed, as is future research.
    Materialart: Digitale Medien
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  • 11
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: One crucial yet relatively unexamined perspective on issues of concern to both organizations and nations, the creativity and productivity of scientific efforts, is the insider perspective. Insiders are privy to confidential information – in this study, first-hand observations of good and bad leadership – because of their position within the laboratory. The insider perspective can help answer such questions as: What are scientists' lived experiences of effective management? What have they observed as some of the impacts of ineffective management? What worries them in terms of their own capacity to lead and manage? This paper describes interim results of an ongoing, exploratory study of insiders in academia, government, and industry. For the past 5 years, more than 200 scientific researchers from Europe, Asia, and the US have been asked open-ended questions about (1) the best example of scientific leadership they have encountered; (2) the worst example; and (3) their most difficult problems leading scientific endeavours. Their responses to date have included unexpected and surprising results. Good leaders are most frequently described as caring and compassionate (in contrast to the expected description of technically competent). Bad leaders are most frequently described as (surprisingly) abusive. The other important (and ‘unintended’) finding is that gender inequity persists. These responses illuminate some of the challenges facing those who manage research and development (R&D), who study the management of R&D, and who are responsible for national policies regarding R&D.
    Materialart: Digitale Medien
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  • 12
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: This paper presents and discusses the contribution of ‘mentoring’ relationships to organisational learning and knowledge creation in the early stages of research and development (R&D) projects. Our study considers the characteristics of a scientific leader, the nature of the context he creates, and how dialogue contributes to scientific breakthrough. Our study is unusual in as much as research on knowledge creation has developed separately, yet in parallel, with that of mentoring. It is rare to combine these disciplines and yet our research shows there is much to learn from examining the two as a process.We conducted our research at TECHNO, a high-tech-based European company producing advanced equipment dedicated to particles acceleration. Interviews were carried out in 2002–2003 with the founder of the company, the head of the R&D and engineering department, and team members involved in the low energy cyclotron project.Our exploratory research enabled us to identify differences in actors' perceptions about the nature and characteristics of these relationships. Our study also suggests that not all sets of relationships can tolerate the degree of intensity provided by the ‘mentor’. TECHNO has other ‘mentors’ who do not manage to generate the same creative context. Complementary mentoring styles based on premises and process reflection allow to support and enhance ‘upper levels’ learning by junior team members. We examine the nature of the leaders as mentors and catalysts within the learning process and briefly discuss implications for setting up and maintaining learning teams.
    Materialart: Digitale Medien
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  • 13
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: The present research uses conversations with new product innovators in commercial organisations to explore how they experience innovating in those organisations. Based on their words, the study explores how innovators experience the complex social settings and structures of their organisation, how this affects creativity, and how innovative climates are enabled or inhibited by it. Organic, self-organising working structures are shown to enable creative commercial innovation more easily than hierarchical settings. Innovators' own words also identify what motivates them. ‘Excitement’ and ‘creative buzz’ are shown to be common intrinsic motivators and ‘tangible benefit’ for organisation or customers is shown to reinforce this. Innovators' experience of networks is also studied, along with their experiences of leadership in organisations. While this study is exploratory in scope, it is hoped that it will be of value in organisations looking to build effective partnerships with their innovators.
    Materialart: Digitale Medien
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  • 14
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: International evidence shows that research is increasingly being carried out in organisational forms built around cross-sectoral (government, academic and business) and transdisciplinary teams with well-defined national social, economic or environmental objectives in view. As a result, new and unfamiliar forms of organisational arrangements for research are emerging within universities and elsewhere. These collaborative research centres have been variously termed ‘hybrid’ or ‘parasitic’. This paper draws upon around 30 in-depth interviews with participants from selected Australian Cooperative Research Centres (CRC). It examines how researchers reconcile the many demands of their dual role, first, as a government researcher or academic, and second as a committed participant in an industry-collaborative research centre. These collaborations go beyond ‘applied research’ to span fundamental research and immediately useful knowledge. But reward systems and performance measures for academic researchers are still founded largely on ‘discovery’, while those for government researchers are based upon ‘application’. The risk is that researchers will be deflected by the collaboration in ways that conflict with their institutional responsibilities. The paper reports work analysing the management strategies used by the CRCs and their public sector partners to ensure that their common goals are achieved while preserving their institutional interests and the expectations of their research staff. The aim is to identify effective ways of managing the various ‘risks’ of cross-sector collaborative research and development (R&D) in Australia and more widely.
    Materialart: Digitale Medien
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  • 15
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: As research and innovation have become central to the economy, the challenge of managing these activities has taken on greater importance. Studies have focused on the impact of organizational variables on research activities, such as work environment, human resource factors, and managerial practices. But little attention has been paid to the effect of differences among types of research projects. While the notion that differences exist among research projects is acknowledged, particularly in the research & development portfolio literature, there have been relatively few studies into the dimensions by which research projects, and needs of project team members, differ. Further, there is little recognition that these differences translate into the need for different research project management practices. The objective of this paper is to investigate differences among research projects along three dimensions, amount of funding, complexity of project teams, and research orientation. These dimensions are selected because of their central theoretical importance in the organizational literature, as well as posing a number of different challenges for research management. This study looked at 18 research projects at a national laboratory and analyzed the responses of project members to a comprehensive research environment survey conducted in 2001. The results of the analysis indicate that there are significant differences between types of projects along three dimensions and suggest ways that research performance can be improved through management intervention.
    Materialart: Digitale Medien
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  • 16
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 35 (2005), S. 0 
    ISSN: 1467-9310
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Profiles of inventors' technological competence are a valuable source of information for decision-making in research and development (R&D) management, e.g. concerning inventor assessment, human resource development and R&D team-building. In the following exposition, a new method of inventor profiling will be put forward, which is based in particular on semantic patent analysis and multidimensional scaling. First, in the course of semantic patent analysis, specialized software, equipped with a natural language processor, reads the patent text transferring the contents into a subject–action–object–format (SAO). The extracted SAO structures are then used to create similarity matrices for patents or patent sets, respectively, according to a specific similarity value. Subsequently, an inventor competence map can be produced by means of multidimensional scaling.The benefits of this method for R&D-related issues in human resource management will be illustrated by the example of a German mechanical engineering company. Two distinct types of profiles were generated and tested: (i) the profile of a single key inventor and (ii) a profile of key inventor sets. The single key inventor profile gives information on the range of competence, i.e. the homogeneity or heterogeneity of a certain inventor's competences, providing far more detailed insights than resorting to bibliographic data like international patent classification (IPC) classes or citations, whereas the latter kind of profile establishes the position of a certain key inventor in relation to others, helping to highlight specific groups of inventors and their domains. These results are clearly apt to support human resource management.
    Materialart: Digitale Medien
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  • 17
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 975-1028 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The conversion of exogenous and endogenous proteins into immunogenic peptides recognized by T lymphocytes involves a series of proteolytic and other enzymatic events culminating in the formation of peptides bound to MHC class I or class II molecules. Although the biochemistry of these events has been studied in detail, only in the past few years has similar information begun to emerge describing the cellular context in which these events take place. This review thus concentrates on the properties of antigen-presenting cells, especially those aspects of their overall organization, regulation, and intracellular transport that both facilitate and modulate the processing of protein antigens. Emphasis is placed on dendritic cells and the specializations that help account for their marked efficiency at antigen processing and presentation both in vitro and, importantly, in vivo. How dendritic cells handle antigens is likely to be as important a determinant of immunogenicity and tolerance as is the nature of the antigens themselves.
    Materialart: Digitale Medien
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  • 18
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 515-548 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The discovery of new functions for the original B7 family members, together with the identification of additional B7 and CD28 family members, have revealed new ways in which the B7:CD28 family regulates T cell activation and tolerance. B7-1/B7-2:CD28 interactions not only promote initial T cell activation but also regulate self-tolerance by supporting CD4+CD25+ T regulatory cell homeostasis. CTLA-4 can exert its inhibitory effects in both B7-1/B7-2 dependent and independent fashions. B7-1 and B7-2 can signal bidirectionally by engaging CD28 and CTLA-4 on T cells and by delivering signals into B7-expressing cells. The five new B7 family members, ICOS ligand, PD-L1 (B7-H1), PD-L2 (B7-DC), B7-H3, and B7-H4 (B7x/B7-S1) are expressed on professional antigen-presenting cells as well as on cells within nonlymphoid organs, providing new means for regulating T cell activation and tolerance in peripheral tissues. The new CD28 families members, ICOS, PD-1, and BTLA, are inducibly expressed on T cells, and they have important roles in regulating previously activated T cells. PD-1 and BTLA also are expressed on B cells and may have broader immunoregulatory functions. The ICOS:ICOSL pathway appears to be particularly important for stimulating effector T cell responses and T cellĐ??dependent B cell responses, but it also has an important role in regulating T cell tolerance. In addition, the PD-1:PD-L1/PD-L2 pathway plays a critical role in regulating T cell activation and tolerance. In this review, we revisit the roles of the B7:CD28 family members in regulating immune responses, and we discuss their therapeutic potential.
    Materialart: Digitale Medien
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  • 19
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 26 (2005), S. 877-900 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Natural killer T (NKT) cells constitute a conserved T cell sublineage with unique properties, including reactivity for a synthetic glycolipid presented by CD1d, expression of an invariant T cell antigen receptor (TCR) ʼ̛ chain, and unusual requirements for thymic selection. They rapidly produce many cytokines after stimulation and thus influence diverse immune responses and pathogenic processes. Because of intensive research effort, we have learned much about factors promoting the development and survival of NKT cells, regulation of their cytokine production, and the means by which they influence dendritic cells and other cell types. Despite this progress, knowledge of the natural antigen(s) they recognize and their physiologic role remain incomplete. The activation of NKT cells paradoxically can lead either to suppression or stimulation of immune responses, and we cannot predict which will occur. Despite this uncertainty, many investigators are hopeful that immune therapies can be developed based on NKT cell stimulation.
    Materialart: Digitale Medien
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  • 20
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 549-600 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The Tec family tyrosine kinases are now recognized as important mediators of antigen receptor signaling in lymphocytes. Three members of this family, Itk, Rlk, and Tec, are expressed in T cells and activated in response to T cell receptor (TCR) engagement. Although initial studies demonstrated a role for these proteins in TCR-mediated activation of phospholipase C-??, recent data indicate that Tec family kinases also regulate actin cytoskeletal reorganization and cellular adhesion following TCR stimulation. In addition, Tec family kinases are activated downstream of G proteinĐ??coupled chemokine receptors, where they play parallel roles in the regulation of Rho GTPases, cell polarization, adhesion, and migration. In all these systems, however, Tec family kinases are not essential signaling components, but instead function to modulate or amplify signaling pathways. Although they quantitatively reduce proximal signaling, mutations that eliminate Tec family kinases in T cells nonetheless qualitatively alter T cell development and differentiation.
    Materialart: Digitale Medien
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  • 21
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 69-99 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The immune response to the malaria parasite is complex and poorly understood. Although antibodies and T cells can control parasite growth in model systems, natural immunity to malaria in regions of high endemicity takes several years to develop. Variation and polymorphism of antibody target antigens are known to impede immune responses, but these factors alone cannot account for the slow acquisition of immunity. In human and animal model systems, cell-mediated responses can control parasite growth effectively, but such responses are regulated by parasite load via direct effects on dendritic cells and possibly on T and B cells as well. Furthermore, high parasite load is associated with pathology, and cell-mediated responses may also harm the host. Inflammatory cytokines have been implicated in the pathogenesis of cerebral malaria, anemia, weight loss, and respiratory distress in malaria. Immunity without pathology requires rapid parasite clearance, effective regulation of the inflammatory antiparasite effects of cellular responses, and the eventual development of a repertoire of antibodies effective against multiple strains. Data suggest that this may be hastened by exposure to malaria antigens in low dose, leading to augmented cellular immunity and rapid parasite clearance.
    Materialart: Digitale Medien
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  • 22
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 23-68 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Several members of the tumor necrosis factor receptor (TNFR) family function after initial T cell activation to sustain T cell responses. This review focuses on CD27, 4-1BB (CD137), OX40 (CD134), HVEM, CD30, and GITR, all of which can have costimulatory effects on T cells. The effects of these costimulatory TNFR family members can often be functionally, temporally, or spatially segregated from those of CD28 and from each other. The sequential and transient regulation of T cell activation/survival signals by different costimulators may function to allow longevity of the response while maintaining tight control of T cell survival. Depending on the disease condition, stimulation via costimulatory TNF family members can exacerbate or ameliorate disease. Despite these complexities, stimulation or blockade of TNFR family costimulators shows promise for several therapeutic applications, including cancer, infectious disease, transplantation, and autoimmunity.
    Materialart: Digitale Medien
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  • 23
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 447-485 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Autoimmunity is a complex process that likely results from the summation of multiple defective tolerance mechanisms. The NOD mouse strain is an excellent model of autoimmune disease and an important tool for dissecting tolerance mechanisms. The strength of this mouse strain is that it develops spontaneous autoimmune diabetes, which shares many similarities to autoimmune or type 1a diabetes (T1D) in human subjects, including the presence of pancreas-specific autoantibodies, autoreactive CD4+ and CD8+ T cells, and genetic linkage to disease syntenic to that found in humans. During the past ten years, investigators have used a wide variety of tools to study these mice, including immunological reagents and transgenic and knockout strains; these tools have tremendously enhanced the study of the fundamental disease mechanisms. In addition, investigators have recently developed a number of therapeutic interventions in this animal model that have now been translated into human therapies. In this review, we summarize many of the important features of disease development and progression in the NOD strain, emphasizing the role of central and peripheral tolerance mechanisms that affect diabetes in these mice. The information gained from this highly relevant model of human disease will lead to potential therapies that may alter the development of the disease and its progression in patients with T1D.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 24
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 101-125 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Recent studies have demonstrated that cell membranes provide a unique environment for protein-protein and protein-lipid interactions that are critical for the assembly and function of the T cell receptor (TCR)-CD3 complex. Highly specific polar interactions among transmembrane (TM) domains that are uniquely favorable in the lipid environment organize the association of the three signaling dimers with the TCR. Each of these three assembly steps depends on the formation of a three-helix interface between one basic and two acidic residues in the membrane environment. The same polar TM residues that drive assembly also play a central role in quality control and export by directing the retention and degradation of free subunits and partial complexes, while membrane proximal cytoplasmic signals control recycling and degradation of surface receptors. Recent studies also suggest that interactions between the membrane and the cytoplasmic domains of CD3 proteins may be important for receptor triggering.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 1-25 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: The author describes studies that led to the resolution and reconstitution of the cytochrome P450 enzyme system in microsomal membranes. The review indicates how purification and characterization of the cytochromes led to rigorous evidence for multiple isoforms of the oxygenases with distinct chemical and physical properties and different but somewhat overlapping substrate specificities. Present knowledge of the individual steps in the P450 and reductase reaction cycles is summarized, including evidence for the generation of multiple functional oxidants that may contribute to the exceptional diversity of the reactions catalyzed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 26
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 51-88 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: This review describes the three mammalian glutathione transferase (GST) families, namely cytosolic, mitochondrial, and microsomal GST, the latter now designated MAPEG. Besides detoxifying electrophilic xenobiotics, such as chemical carcinogens, environmental pollutants, and antitumor agents, these transferases inactivate endogenous ʼ̛,?‚-unsaturated aldehydes, quinones, epoxides, and hydroperoxides formed as secondary metabolites during oxidative stress. These enzymes are also intimately involved in the biosynthesis of leukotrienes, prostaglandins, testosterone, and progesterone, as well as the degradation of tyrosine. Among their substrates, GSTs conjugate the signaling molecules 15-deoxy-??12,14-prostaglandin J2 (15d-PGJ2) and 4-hydroxynonenal with glutathione, and consequently they antagonize expression of genes trans-activated by the peroxisome proliferator-activated receptor ?? (PPAR??) and nuclear factor-erythroid 2 p45-related factor 2 (Nrf2). Through metabolism of 15d-PGJ2, GST may enhance gene expression driven by nuclear factor-?”B (NF-?”B). Cytosolic human GST exhibit genetic polymorphisms and this variation can increase susceptibility to carcinogenesis and inflammatory disease. Polymorphisms in human MAPEG are associated with alterations in lung function and increased risk of myocardial infarction and stroke. Targeted disruption of murine genes has demonstrated that cytosolic GST isoenzymes are broadly cytoprotective, whereas MAPEG proteins have proinflammatory activities. Furthermore, knockout of mouse GSTA4 and GSTZ1 leads to overexpression of transferases in the Alpha, Mu, and Pi classes, an observation suggesting they are part of an adaptive mechanism that responds to endogenous chemical cues such as 4-hydroxynonenal and tyrosine degradation products. Consistent with this hypothesis, the promoters of cytosolic GST and MAPEG genes contain antioxidant response elements through which they are transcriptionally activated during exposure to Michael reaction acceptors and oxidative stress.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 27
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 177-202 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: The importance of reactive metabolites in the pathogenesis of drug-induced toxicity has been a focus of research interest since pioneering investigations in the 1950s revealed the link between toxic metabolites and chemical carcinogenesis. There is now a great deal of evidence that shows that reactive metabolites are formed from drugs known to cause hepatotoxicity, but how these toxic species initiate and propagate tissue damage is still poorly understood. This review summarizes the evidence for reactive metabolite formation from hepatotoxic drugs, such as acetaminophen, tamoxifen, diclofenac, and troglitazone, and the current hypotheses of how this leads to liver injury. Several hepatic proteins can be modified by reactive metabolites, but this in general equates poorly with the extent of toxicity. Much more important may be the identification of the critical proteins modified by these toxic species and how this alters their function. It is also important to note that the toxicity of reactive metabolites may be mediated by noncovalent binding mechanisms, which may also have profound effects on normal liver physiology. Technological developments in the wake of the genomic revolution now provide unprecedented power to characterize and quantify covalent modification of individual target proteins and their functional consequences; such information should dramatically improve our understanding of drug-induced hepatotoxic reactions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 28
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 291-310 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: The cytochrome P450 monooxygenases (CYPs) are the dominant enzyme system responsible for xenobiotic detoxification and drug metabolism. Several CYP isoforms exhibit non-Michaelis-Menten, or "atypical," steady state kinetic patterns. The allosteric kinetics confound prediction of drug metabolism and drug-drug interactions, and they challenge the theoretical paradigms of allosterism. Both homotropic and heterotropic ligand effects are now widely documented. It is becoming apparent that multiple ligands can simultaneously bind within the active sites of individual CYPs, and the kinetic parameters change with ligand occupancy. In fact, the functional effect of any specific ligand as an activator or inhibitor can be substrate dependent. Divergent approaches, including kinetic modeling and X-ray crystallography, are providing new information about how multiple ligand binding yields complex CYP kinetics.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 29
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 335-355 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: Recent discoveries of novel and potentially important biological activity have spurred interest in the chemistry and biochemistry of nitroxyl (HNO). It has become clear that, among all the nitrogen oxides, HNO is unique in its chemistry and biology. Currently, the intimate chemical details of the biological actions of HNO are not well understood. Moreover, many of the previously accepted chemical properties of HNO have been recently revised, thus requiring reevaluation of possible mechanisms of biological action. Herein, we review these developments in HNO chemistry and biology.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 30
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 385-412 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: Adenosine and its receptors have been the topic of many recent reviews ( 1Đ??26 ). These reviews provide a good summary of much of the relevant literatureĐ??including the older literature. We have, therefore, chosen to focus the present review on the insights gained from recent studies on genetically modified mice, particularly with respect to the function of adenosine receptors and their potential as therapeutic targets. The information gained from studies of drug effects is discussed in this context, and discrepancies between genetic and pharmacological results are highlighted.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 31
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 657-687 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: Cardiac fibroblasts play a central role in the maintenance of extracellular matrix in the normal heart and as mediators of inflammatory and fibrotic myocardial remodeling in the injured and failing heart. In this review, we evaluate the cardiac fibroblast as a therapeutic target in heart disease. Unique features of cardiac fibroblast cell biology are discussed in relation to normal and pathophysiological cardiac function. The contribution of cardiac fibrosis as an independent risk factor in the outcome of heart failure is considered. Candidate drug therapies that derive benefit from actions on cardiac fibroblasts are summarized, including inhibitors of angiotensin-aldosterone systems, endothelin receptor antagonists, statins, anticytokine therapies, matrix metalloproteinase inhibitors, and novel antifibrotic/anti-inflammatory agents. These findings point the way to future challenges in cardiac fibroblast biology and pharmacotherapy.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 32
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 367-386 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: In vertebrates, serum antibodies are an essential component of innate and adaptive immunity and immunological memory. They also can contribute significantly to immunopathology. Their composition is the result of tightly regulated differentiation of B lymphocytes into antibody-secreting plasma blasts and plasma cells. The survival of antibody-secreting cells determines their contribution to the immune response in which they were generated and to long-lasting immunity, as provided by stable serum antibody levels. Short-lived plasma blasts and/or plasma cells secrete antibodies for a reactive immune response. Short-lived plasma blasts can become long-lived plasma cells, probably by competition with preexisting plasma cells for occupation of a limited number of survival niches in the body, in a process not yet fully understood. Limitation of the number of long-lived plasma cells allows the immune system to maintain a stable humoral immunological memory over long periods, to react to new pathogenic challenges, and to adapt the humoral memory in response to these antigens.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 33
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 337-366 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: C reactive protein, the first innate immunity receptor identified, and serum amyloid P component are classic short pentraxins produced in the liver. Long pentraxins, including the prototype PTX3, are expressed in a variety of tissues. Some long pentraxins are expressed in the brain and some are involved in neuronal plasticity and degeneration. PTX3 is produced by a variety of cells and tissues, most notably dendritic cells and macrophages, in response to Toll-like receptor (TLR) engagement and inflammatory cytokines. PTX3 acts as a functional ancestor of antibodies, recognizing microbes, activating complement, and facilitating pathogen recognition by phagocytes, hence playing a nonredundant role in resistance against selected pathogens. In addition, PTX3 is essential in female fertility because it acts as a nodal point for the assembly of the cumulus oophorus hyaluronan-rich extracellular matrix. Thus, the prototypic long pentraxin PTX3 is a multifunctional soluble pattern recognition receptor at the crossroads between innate immunity, inflammation, matrix deposition, and female fertility.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 34
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 225-274 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The integrated processing of signals transduced by activating and inhibitory cell surface receptors regulates NK cell effector functions. Here, I review the structure, function, and ligand specificity of the receptors responsible for NK cell recognition.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 35
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 787-819 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Lymphotoxins (LT) provide essential communication links between lymphocytes and the surrounding stromal and parenchymal cells and together with the two related cytokines, tumor necrosis factor (TNF) and LIGHT (LT-related inducible ligand that competes for glycoprotein D binding to herpesvirus entry mediator on T cells), form an integrated signaling network necessary for efficient innate and adaptive immune responses. Recent studies have identified signaling pathways that regulate several genes, including chemokines and interferons, which participate in the development and function of microenvironments in lymphoid tissue and host defense. Disruption of the LT/TNF/LIGHT network alleviates inflammation in certain autoimmune disease models, but decreases resistance to selected pathogens. Pharmacological disruption of this network in human autoimmune diseases such as rheumatoid arthritis alleviates inflammation in a significant number of patients, but not in other diseases, a finding that challenges our molecular paradigms of autoimmunity and perhaps will reveal novel roles for this network in pathogenesis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 36
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 387-414 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The newly discovered CATERPILLER (CLR) gene family encodes proteins with a variable but limited number of N-terminal domains, followed by a nucleotide-binding domain (NBD) and leucine-rich repeats (LRR). The N-terminal domain consists of transactivation, CARD, Pyrin, or BIR domains, with a minority containing undefined domains. These proteins are remarkably similar in structure to the TIR-NBD-LRR and CC-NBD-LRR disease resistance (R) proteins that mediate immune responses in plants. The NBD-LRR architecture is conserved in plants and vertebrates, but only remnants are found in worms and flies. The CLRs regulate inflammatory and apoptotic responses, and some act as sensors that detect pathogen products. Several CLR genes have been genetically linked to susceptibility to immunologic disorders. We describe prominent family members, including CIITA, CARD4/NOD1, NOD2/CARD15, CIAS1, CARD7/NALP1, and NAIP, in more detail. We also discuss implied roles of these proteins in diversifying immune detection and in providing a check-and-balance during inflammation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 37
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 901-944 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Macrophages express a broad range of plasma membrane receptors that mediate their interactions with natural and altered-self components of the host as well as a range of microorganisms. Recognition is followed by surface changes, uptake, signaling, and altered gene expression, contributing to homeostasis, host defense, innate effector mechanisms, and the induction of acquired immunity. This review covers recent studies of selected families of structurally defined molecules, studies that have improved understanding of ligand discrimination in the absence of opsonins and differential responses by macrophages and related myeloid cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 38
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 601-649 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: T cell development is guided by a complex set of transcription factors that act recursively, in different combinations, at each of the developmental choice points from T-lineage specification to peripheral T cell specialization. This review describes the modes of action of the major T-lineage-defining transcription factors and the signal pathways that activate them during intrathymic differentiation from pluripotent precursors. Roles of Notch and its effector RBPSuh (CSL), GATA-3, E2A/HEB and Id proteins, c-Myb, TCF-1, and members of the Runx, Ets, and Ikaros families are critical. Less known transcription factors that are newly recognized as being required for T cell development at particular checkpoints are also described. The transcriptional regulation of T cell development is contrasted with that of B cell development, in terms of their different degrees of overlap with the stem-cell program and the different roles of key transcription factors in gene regulatory networks leading to lineage commitment.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 39
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 307-335 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The significance of type I interferons (IFN-ʼ̛/?‚) in biology and medicine renders research on their activities continuously relevant to our understanding of normal and abnormal (auto) immune responses. This relevance is bolstered by discoveries that unambiguously establish IFN-ʼ̛/?‚, among the multitude of cytokines, as dominant in defining qualitative and quantitative characteristics of innate and adaptive immune processes. Recent advances elucidating the biology of these key cytokines include better definition of their complex signaling pathways, determination of their importance in modifying the effects of other cytokines, the role of Toll-like receptors in their induction, their major cellular producers, and their broad and diverse impact on both cellular and humoral immune responses. Consequently, the role of IFN-ʼ̛/?‚ in the pathogenesis of autoimmunity remains at the forefront of scientific inquiry and has begun to illuminate the mechanisms by which these molecules promote or inhibit systemic and organ-specific autoimmune diseases.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 40
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 127-159 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Secondary lymphoid organs serve as hubs for the adaptive immune system, bringing together antigen, antigen-presenting cells, and lymphocytes. Two families of G proteinĐ??coupled receptors play essential roles in lymphocyte migration through these organs: chemokine receptors and sphingosine-1-phosphate (S1P) receptors. Chemokines expressed by lymphoid stromal cells guide lymphocyte and dendritic cell movements during antigen surveillance and the initiation of adaptive immune responses. S1P receptor-1 is required for lymphocyte egress from thymus and secondary lymphoid organs and is downregulated by the immunosuppressive drug FTY720. Here, we review the steps associated with the initiation of adaptive immune responses in secondary lymphoid organs, highlighting the roles of chemokines and S1P.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 41
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 749-786 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: This review focuses on recent progress in our understanding of how mast cells can contribute to the initiation, development, expression, and regulation of acquired immune responses, both those associated with IgE and those that are apparently expressed independently of this class of Ig. We emphasize findings derived from in vivo studies in mice, particularly those employing genetic approaches to influence mast cell numbers and/or to alter or delete components of pathways that can regulate mast cell development, signaling, or function. We advance the hypothesis that mast cells not only can function as proinflammatory effector cells and drivers of tissue remodeling in established acquired immune responses, but also may contribute to the initiation and regulation of such responses. That is, we propose that mast cells can also function as immunoregulatory cells. Finally, we show that the notion that mast cells have primarily two functional configurations, off (or resting) or on (or activated for extensive mediator release), markedly oversimplifies reality. Instead, we propose that mast cells are "tunable," by both genetic and environmental factors, such that, depending on the circumstances, the cell can be positioned phenotypically to express a wide spectrum of variation in the types, kinetics, and/or magnitude of its secretory functions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 42
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 1-21 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: This essay summarizes my 40 years of research in immunology. As a young physician, I encountered a patient with Waldenstro?m's macroglobulinemia, and this inspired me to study the structure of IgM. I began to ask how antibody responses are regulated. In the late 1960s, the essential role of T cells in antibody production had been reported. In search of molecules mediating T cell helper function, I discovered activities in the culture supernatant of T cells that induced proliferation and differentiation of B cells. This led to my life's work: studying one of those factors, interleukin-6 (IL-6). To my surprise, IL-6 turned out to play additional roles, including myeloma growth factor and hepatocyte-stimulating factor activities. More importantly, it was involved in a number of diseases, such as rheumatoid arthritis and Castleman's disease. I feel exceptionally fortunate that my work not only revealed the framework of cytokine signaling, including identification of the IL-6 receptor, gp130, NF-IL6, STAT3, and SOCS-1, but also led to the development of a new therapy for chronic inflammatory diseases.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 43
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 853-875 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Most mammalian cells have nuclei that contain DNA, which replicates during cell proliferation. DNA is destroyed by various developmental processes in mammals. It is degraded during programmed cell death that accompanies mammalian development. The nuclei of erythrocytes and eye lens fiber cells are also removed during their differentiation into mature cells. If DNA is not properly degraded in these processes, it can cause various diseases, including tissue atrophy, anemia, cataract, and autoimmune diseases, which indicates that DNA can be a pathogenic molecule. Here, I present how DNA is degraded during programmed cell death, erythroid cell differentiation, and lens cell differentiation. I discuss what might be or will be learned from understanding the molecular mechanisms of DNA degradation that occurs during mammalian development.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 44
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 465-476 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: Normal cellular functioning requires processing of proteins regulating cell cycle, growth, and apoptosis. The ubiquitin-proteasome pathway (UBP) modulates intracellular protein degradation. Specifically, the 26S proteasome is a multienzyme protease that degrades misfolded or redundant proteins; conversely, blockade of the proteasomal degradation pathways results in accumulation of unwanted proteins and cell death. Because cancer cells are more highly proliferative than normal cells, their rate of protein translation and degradation is also higher. This notion led to the development of proteasome inhibitors as therapeutics in cancer. The FDA recently approved the first proteasome inhibitor bortezomib (VelcadeĐ?„), formerly known as PS-341, for the treatment of newly diagnosed and relapsed/refractory multiple myeloma (MM). Ongoing studies are examining other novel proteasome inhibitors, in addition to bortezomib, for the treatment of MM and other cancers.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 45
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Pharmacology 45 (2005), S. 565-585 
    ISSN: 0362-1642
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Medizin , Chemie und Pharmazie
    Notizen: The enormous public health problem posed by malaria has been substantially worsened in recent years by the emergence and worldwide spread of drug-resistant parasites. The utility of two major therapies, chloroquine and the synergistic combination of pyrimethamine/sulfadoxine, is now seriously compromised. Although several genetic mechanisms have been described, the major source of drug resistance appears to be point mutations in protein target genes. Clinically significant resistance to these agents requires the accumulation of multiple mutations, which genetic studies of parasite populations suggest arise focally and sweep through the population. Efforts to circumvent resistance range from the use of combination therapy with existing agents to laboratory studies directed toward discovering novel targets and therapies. The prevention and management of drug resistance are among the most important practical problems of tropical medicine and public health. Leonard J. Bruce-Chwatt, 1972
    Materialart: Digitale Medien
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  • 46
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 197-223 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Neutrophils provide the first line of defense of the innate immune system by phagocytosing, killing, and digesting bacteria and fungi. Killing was previously believed to be accomplished by oxygen free radicals and other reactive oxygen species generated by the NADPH oxidase, and by oxidized halides produced by myeloperoxidase. We now know this is incorrect. The oxidase pumps electrons into the phagocytic vacuole, thereby inducing a charge across the membrane that must be compensated. The movement of compensating ions produces conditions in the vacuole conducive to microbial killing and digestion by enzymes released into the vacuole from the cytoplasmic granules.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 47
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 821-852 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: The complement system not only represents an effective innate immune mechanism of host defense to eradicate microbial pathogens, but it is also widely involved in many forms of acute and chronic inflammatory diseases including sepsis, acute lung injury, ischemia-reperfusion injury, and asthma, to give just a few examples. The complement-activated product, C5a, displays powerful biological activities that lead to inflammatory sequelae. C5a is a strong chemoattractant and is involved in the recruitment of inflammatory cells such as neutrophils, eosinophils, monocytes, and T lymphocytes, in activation of phagocytic cells and release of granule-based enzymes and generation of oxidants, all of which may contribute to innate immune functions or tissue damage. Accumulating data suggest that C5a provides a vital bridge between innate and adaptive immune functions, extending the roles of C5a in inflammation. Herein, we review human and animal data describing the cellular and molecular mechanisms of C5a in the development of inflammatory disorders, sepsis, acute lung injury, ischemia-reperfusion injury, and asthma.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 48
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Immunology 23 (2005), S. 275-306 
    ISSN: 0732-0582
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie , Medizin
    Notizen: Type 1 interferon-(ʼ̛, ?‚, ?)-producing cells (IPCs), also known as plasmacytoid dendritic cell precursors (pDCs), represent 0.2%Đ??0.8% of peripheral blood mononuclear cells in both humans and mice. IPCs display plasma cell morphology, selectively express Toll-like receptor (TLR)-7 and TLR9, and are specialized in rapidly secreting massive amounts of type 1 interferon following viral stimulation. IPCs can promote the function of natural killer cells, B cells, T cells, and myeloid DCs through type 1 interferons during an antiviral immune response. At a later stage of viral infection, IPCs differentiate into a unique type of mature dendritic cell, which directly regulates the function of T cells and thus links innate and adaptive immune responses. After more than two decades of effort by researchers, IPCs finally claim their place in the hematopoietic chart as the most important cell type in antiviral innate immunity. Understanding IPC biology holds future promise for developing cures for infectious diseases, cancer, and autoimmune diseases.
    Materialart: Digitale Medien
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  • 49
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: This article reports on the union recognition dispute that took place at the McDonald's food-processing plant in Moscow. It examines this dispute in the context of McDonald's employment practices worldwide, the interventions made by international and local unions, and Russian government bodies. Despite these interventions it became impossible to either organise the workforce or establish a collective agreement. The case illustrates the difficulties facing both local unions and global union federations when confronted by intransigent multinational companies, especially in low-skilled sectors in transitional economies.
    Materialart: Digitale Medien
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  • 50
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: This paper is concerned with exploring the barriers to cross-border trade union cooperation among graphical workers in Europe. Highlighting the increasing globalisation of graphical multinationals, the paper illustrates that graphical unions cannot restrict their activities to developments within national boundaries. As such it highlights some of the obstacles that unions face in attempting to instigate transnational cooperation strategies. These obstacles include: the role of employers, the prevailing practices of the unions, employee reticence, the role of the law and resource constraints. It concludes by stressing the continuing need to strengthen cross-border trade union networks with the ability to impose effective sanctions against the unbridled growth of multinational power.
    Materialart: Digitale Medien
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  • 51
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Books reviewed:John T. Addison and Claus Schnabel (eds). International Handbook of Trade Unions
Reviewed by John KellyWalter Müller-Jentsch and Hansjörg Weitbrecht (eds). The Changing Contours of German Industrial Relations
Reviewed by Steve FrenchYonatan Reshef and Sandra Rastin. Unions in the Time of Revolution. Government Restructuring in Alberta and Ontario
Reviewed by Roy J. Adams
    Materialart: Digitale Medien
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  • 52
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: A lower national minimum wage for 18- to 21-year-olds and the exclusion of all workers under 18 prompted fears of a distortion in the British labour market and an undermining of training initiatives. Empirical data collected from employers in two low paying sectors, revealing the full utilisation of young workers and under-utilisation of training initiatives, ensure these fears are not justified and that the government's basis for the lower rate cannot be substantiated.
    Materialart: Digitale Medien
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  • 53
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: The French system of continuing vocational training was set up in 1970 by an intersectoral collective agreement that was then followed by legislation. More than 30 years on, the economic and social context has changed and the system now faces new challenges. In 2001 and again in 2003 the social partners embarked upon new negotiations in a bid to redesign the system. Analysis of the negotiation process and of its outcomes  reveals  both  the  persistence  of  societal  characteristics  and  the  emergence  of significant innovations, particularly in the individualisation of training. This dual trend is explained by the characteristics of the actors involved as well as by the weakness of the state.
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  • 54
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Books reviewed: Decentralised Pay Setting: A Study of the Outcomes of Collective Bargaining Reforms in the Civil Service in Australia, Sweden and the UK 
K. A. Bender and R. F. Elliott 
Ashgate, 2003, xii + 160 pp., £50.00 A Very Late Development: An Autobiography 
Alan Fox 
British Universities Industrial Relations Association, 2nd and revised edition, 2004, 306 pp., £8.00 (paperback) Unions in the 21st Century: An International Perspective 
Anil Verma and Thomas A. Kochan (eds) 
Palgrave Macmillan, 2004, 296 pp., £50.00 The Management of Human Resources in the Asia Pacific Region: Convergence Reconsidered 
Chris Rowley and John Benson (eds)
Cass (Studies in Asia Pacific Business), 2004, 208 pp., £18.99
    Materialart: Digitale Medien
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  • 55
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: The extraordinary growth in foreign direct investment coupled with the widespread declination of union penetration has increasingly allowed multinationals to pit unions across borders as competitors for investment and jobs. Based on a theoretical analysis of the exercise of power in a prisoner's dilemma game, the essential conditions and incentives for cooperation among unions across borders for the purpose of collective bargaining with multinationals are identified and practical, strategic-level implications for transnational interunion partnerships are addressed.
    Materialart: Digitale Medien
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  • 56
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: There has been a growing interest in the way patterns of employment relations are changing in China. However, there remains insufficient understanding in employment relations in small private businesses. This study of small businesses in China explores major issues in employment relations in these firms. The finding shows that there are major differences between large and small businesses in China in their employment practices and that considerable similarities exist between small firms in China and those in other countries.
    Materialart: Digitale Medien
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  • 57
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: In response to Schmidt, Le, and Ilies' (2003) call for further assessment of transient error variance in measures of key individual difference variables, the current study examines transient error estimates for eight speeded cognitive ability scales and a composite scale. One hundred twenty-three participants were tested on two occasions with a 1-week interval between administrations. Estimates of transient error ranged from a low of .01 to a high of .18, with an average value of .09. The coefficient of equivalence, based on the split-half method, resulted in overestimates of reliability by as little as 1.90% to as much as 25.96%, with an average 12.96%.
    Materialart: Digitale Medien
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  • 58
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Although recruitment researchers often discuss influences on decisions to apply for jobs, few studies assess actual application behavior. This study of individuals who expressed an interest in a firefighter job revealed that applying was related to recruiting source informativeness and organizational familiarity. Source informativeness was not related to self-selection out of the process after application or performance on the selection process, but was related to perceptions of familiarity and to applicant demographics. Implications for recruitment are discussed.
    Materialart: Digitale Medien
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  • 59
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 60
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Critics and advocates of union–management partnership agreements offer competing assessments of the potential outcomes for workplace union representation. These include the attenuation of the role of lay activists and intra-union conflict. In this case study of Amicus-MSF at Legal & General partnership involved centralised decision making, membership loss and activist-leadership tensions, but these were temporary. With employer support the local union leadership ‘cultivated’ a cadre of pro-partnership activists with extended reach into management decision making, increasing membership and strengthening workplace organisation.
    Materialart: Digitale Medien
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  • 61
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: An international foundation for the promotion of basic research in biomedicine, the Boehringer Ingelheim Fonds (B.I.F.), reports that fellowships are awarded to post-graduate researchers according to the following main criteria: (1) scientific quality as demonstrated by the applicant's achievements to date, (2) the originality of the proposed research project, and (3) the scientific standing of the laboratory where the research will be conducted. Using the Boolean probit statistical technique, this study examines the multiple conjunctural causation that a fellowship will be awarded only if all three of these criteria are assessed positively by the B.I.F. peer review committee. In agreement with the prescriptive principles of the foundation the results suggest that the B.I.F. approves applications only if all of the three criteria are rated positively.
    Materialart: Digitale Medien
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  • 62
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Industrial relations journal 36 (2005), S. 0 
    ISSN: 1468-2338
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: This paper identifies the constraints and opportunities facing trade unions in post-socialist societies through a comparison of the Russian and Chinese cases. The paper charts the changing role of trade unions in the integration of state-socialist economies into global capitalism and argues that this presents the trade unions with a dilemma: whether to reconstitute their traditional role through collaboration with management and the state apparatus, or whether to develop their ability to defend the rights and interests of workers. While the former offers the line of least resistance, there are progressive elements pushing for change in both trade union movements.
    Materialart: Digitale Medien
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  • 63
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Standardized tests are commonly used to select individuals in both pre-employment and educational settings. Nevertheless, research has yet to sufficiently explore the relationship between test anxiety (TA) and test performance in selection contexts. The goal of this study was to assess the dimensionality of TA, the relations between TA and test performance, and the impact of gender on TA within the realm of personnel selection. Test anxiety was found to be bi-dimensional and negatively related to performance on a cognitively based selection instrument. Gender moderated the relation between TA and test performance, with stronger associations for males. This finding is consistent with the sex-linked anxiety coping theory that is advanced here. Implications of this study and avenues for future research are discussed.
    Materialart: Digitale Medien
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  • 64
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: A situational judgment test (SJT) and a Big 5 personality test were administered to 203 participants under instructions to respond honestly and to fake good using a within-subjects design. Participants indicated both the best and worst response (i.e., Knowledge) and the most likely and least likely response (i.e., Behavioral Tendency) to each situation. Faking effect size for the SJT Behavioral Tendency response format was (d=.34) when participants responded first under honest instructions and (d=.15) when they responded first under faking instructions. Those for the Big 5 dimensions ranged from d=.26 to d=1.0. For the Knowledge response format results were inconsistent. Honest condition Knowledge SJT scores were more highly correlated with cognitive ability (r=.56) than were Behavioral Tendency SJT scores (r=.38). Implications for researchers and practitioners are discussed.
    Materialart: Digitale Medien
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  • 65
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Applied psychologists have long been interested in the relationship between applicant personality and employment interview ratings. Analysis of data from two studies, one using a situational interview and one using a behavioral interview, suggests that the correlations of structured interview ratings with self-report measures of personality factors are generally rather low. Further, a small meta-analysis integrates these two studies and the limited previous literature to arrive at a similar conclusion – there is relatively little relationship between structured interviews and self-reported personality factors.
    Materialart: Digitale Medien
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  • 66
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: In this study, we investigated the moderating role of interdependence (a personality trait that measures the extent to which individuals desire working in a group-based, cooperative setting) on the relationship between competitiveness and one-year objective sales performance. On the basis of data from 133 sales representatives, results indicated that: (a) competitiveness was related to objective sales performance; and (b) interdependence moderated the relationship between competitiveness and objective sales performance such that competitiveness predicted objective sales performance more strongly for those who scored low in interdependence versus those who scored high in interdependence. Implications for sales selection and reward systems and directions for future research are considered.
    Materialart: Digitale Medien
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  • 67
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Recruiters infer personal traits from job applicants' resumés and use these inferences in evaluating job applicants' employability. No research to date, however, has determined if resumé reviewers' inferences of applicants' personality drawn solely from resumé biographical data are valid. In the present study, resumé reviewers (N=52) examined one of two applicant resumés and then described the applicant's personality based on the Big 5 taxonomy. Validities of reviewers' inferences concerning applicant personality were assessed by correlating resumé reviewers' judgments with applicants' self-reported Big 5 personality scores. Results suggested that valid personality inferences are possible based solely on resumé evaluation. We also found evidence suggesting that attending a brief training session may enhance reviewers' accuracy when inferring applicants' personality from resumé information.
    Materialart: Digitale Medien
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  • 68
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    International journal of selection and assessment 13 (2005), S. 0 
    ISSN: 1468-2389
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Wirtschaftswissenschaften
    Notizen: Although there has been empirical attention paid to the criterion-related validity of predictor composites, there has been much less attention paid to the standardized ethnic group differences associated with these composites. One important area of inquiry in predictor composite research is the influence of adding predictors to a test of general mental ability. The limited empirical literature on this practice is mixed, but the prevailing expectation is that there is likely to be higher validity and less adverse impact. Unfortunately, much of the previous work is limited by the presence of inaccurate validity and standardized ethnic group difference values. In this analysis we formed meta-analytic matrices to more accurately estimate the validity and standardized ethnic group differences of several composites that combine a measure of cognitive ability with measures of conscientiousness, a structured interview, or biodata. While results were somewhat complex, we found that adding alternative predictors does not result in a situation in which validity automatically goes up and adverse impact potential automatically goes down. In fact, the reductions in adverse impact (if any) from adding “non-cognitive” predictors were more modest than much of the literature suggests.
    Materialart: Digitale Medien
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  • 69
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. The two approaches most commonly applied to characterizing the chemical form and ‘reactivity’ of metals in the soil solid phase are sequential extraction procedures (SEPs) and isotopic dilution (ID). The development and limitations of both approaches are described and their application to contaminated soils discussed. It may be argued that ID offers a better means of discriminating between ‘reactive’ and ‘inert’ forms of metal. However, the literature on SEPs is considerably larger, providing greater scope for comparative analysis of new data. Although ID methods are subject to operational constraints, the procedural dependency of SEPs is probably much greater. Thus greater effort has been expended to standardize and verify methodologies for SEPs. However, despite achieving a level of ‘political ratification’ at the procedural level, the use of SEPs within risk assessments for planning or development purposes is currently almost absent. The future for ID methods in this context may lie in site-specific risk assessments that include improved methods for the prediction of metal solubility and bioavailability.
    Materialart: Digitale Medien
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  • 70
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Chemical analysis alone is inadequate for comprehensively assessing the impact of soil pollution on biota. The term bioavailability can only be applied in a context specific to a target biological receptor or a proven chemical surrogate. Integration of biological and chemical data can often yield significant advances in hazard assessment and act as a suitable baseline for making site-specific risk assessments. Here, the value of biological techniques is discussed and their application described. The relative merit of test selection is considered and the new direction being developed in sublethal assessments. Currently, however, one of the major limitations is the seeming lack of flexibility of many assays in that they are either applicable to agricultural systems or industrial scenarios, but rarely to both. As a consequence, few assays have internationally adopted protocols. The introduction of new methods and the continued improvement and refinement of assays make this area of soil science dynamic and responsive.
    Materialart: Digitale Medien
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  • 71
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. A current global trend towards intensification or specialization of agricultural enterprises has been accompanied by increasing public awareness of associated environmental consequences. Air and water pollution from losses of nutrients, such as nitrogen (N) and sulphur (S), are a major concern. Governments have initiated extensive regulatory frameworks, including various land use policies, in an attempt to control or reduce the losses. This paper presents an overview of critical input and loss processes affecting N and S for temperate climates, and provides some background to the discussion in subsequent papers evaluating specific farming systems. Management effects on potential gaseous and leaching losses, the lack of synchrony between supply of nutrients and plant demand, and options for optimizing the efficiency of N and S use are reviewed. Integration of inorganic and organic fertilizer inputs and the equitable re-distribution of nutrients from manure are discussed. The paper concludes by highlighting a need for innovative research that is also targeted to practical approaches for reducing N and S losses, and improving the overall synchrony between supply and demand.
    Materialart: Digitale Medien
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  • 72
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Sustainable management of nutrients in agricultural systems is critical for sufficient production of nutritious foods and to minimize environmental pollution. In this overview, we discuss some of the most important factors influencing nutrient cycling, and how practices for sustainable nutrient management can be optimized. In most cases, problems are associated with excessive use of nutrients (manures, other organic amendments, and inorganic fertilizers). Options for dealing with such problems at the farm level include: reducing nutrient inputs to balance exports, increasing the land area on which manures are applied, and export of excess nutrients from the farm in the form of value-added products. These strategies can be used singly, or in combination. Nutrients in the human food chain are often not recycled back to primary crop production. To manage such issues, and avoid regional nutrient accumulations, we need to develop a better understanding of large-scale nutrient flows, and develop policies to manage them. We stress the importance of scale when considering nutrient management in the future.
    Materialart: Digitale Medien
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  • 73
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. The practice of large phosphorus (P) additions to agricultural land has resulted in an increased depletion of limited mineable rock phosphate resources, P accumulation in soils with an increased risk for P losses, and intensified eutrophication and deterioration of water quality in recipient water bodies. A number of measures have been used to reach balance between P inputs and outputs in agricultural systems, with the goal of achieving improved P use efficiency, sustained high crop yields and reduced P losses. This paper discusses how this goal may be achieved. Results from a Swedish long-term fertility experiment combined with results of a P leaching study using a selection of soils from the fertility experiment are used to evaluate the effects of a balanced P system on yields, soil P levels and P leaching. Three P fertilizer application strategies are compared (zero P, replacement P, and a treatment where surplus P fertilization was used to achieve a rapid increase in the soil P status). The replacement P strategy appeared to be the most sustainable system but P fixation in this system must be accounted for. When surplus P rates were applied, increased crop yields were counterbalanced by poorer use efficiency and P accumulation in soil. Topsoil P content was a poor predictor of P leaching. Instead, balancing P inputs and outputs represents a first step in the management of P losses, but additional, site-specific measures are required to counteract site-specific factors responsible for P losses.
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  • 74
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Low input grazing-based meat production is often practised on land where alternative land use is restricted and where high biodiversity warrants specific environmental payments. Although these systems are characterized by low external nutrient inputs, significant nutrient losses may occur per unit of produce, even though losses per unit area are low. If the aim is to have animal production without further eutrophication of watercourses, these losses should be minimized,. However, if nutrient-poor grasslands characterized by high biodiversity are the aim, some losses must be accepted to balance nutrient inputs by atmospheric deposition. The impact of grazing animals on nutrient dynamics in grasslands is reviewed in this paper, and options to further improve nutrient management are discussed. It is concluded that nutrient management should largely be addressed indirectly through management of animal behaviour in relation to grazing and supplemental feeding, as well as through optimization of the seasonal distribution of livestock size. A case study indicated that N losses from a cattle farm could be reduced considerably by these means, while animal production could actually be improved. Sustainability issues and trends in legislative and social pressures on low input grazing-based systems of animal production are discussed in relation to nutrient management and practical recommendations.
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  • 75
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Book reviewed in this article: Below-ground interactions in tropical agroecosystems: concepts and models with multiple plant components. M. van Noordwijk, G. Cadish and C. K. Ong (Editors).
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  • 76
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Book reviewed in this article: Good statistical practice for natural resources research. By R.D. Stone, R. Coe, E.F. Allan and I.C. Dale (Editors).
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  • 77
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. A model of soil variability as a continuous background process with superimposed point contamination was applied to 569 measurements of metal concentrations (Cr, Ni and Pb) in the topsoils of Sheffield, England. Robust estimators of the variogram were shown to be required to describe spatial variation of the metal concentrations at most sampled locations. This is diagnostic of the presence of a contaminant process. Values of the standardized kriging error from the cross-validation of each datum were used to identify spatial outliers for each metal. The ordinary kriged estimates of Cr, Ni and Pb were mapped after removing the outliers to estimate the background variation. Each of the 35 spatial outliers that occured in gardens have concentrations exceeding their Soil Guideline Value for residential land use with plant uptake, highlighting a potentially significant exposure pathway. The frequent observation of coal and furnace waste at these sites suggests that their dispersal, following domestic use and industrial processes, respectively, represents a significant point contaminant process. There was no evidence for spatial clustering of the point process. However, the spatial outliers of Cr and Ni showed a significant association with disturbed sites identified from historical land use maps, in part due to their prevalence in areas of historical steel manufacture. The magnitude of diffuse pollution for each metal in the urban soil was estimated by removing the spatial outliers and comparing robust measures of location with those from a survey of soils developed over the same parent materials in adjacent rural and peri-urban environments. The Winsorized mean Pb concentrations in urban topsoil (203 mg kg−1) were twice the value in the rural environment (101 mg kg−1), highlighting a very substantial diffuse Pb load to urban soils. The equivalent estimated diffuse components in urban soils for Cr and Ni were, respectively, 25% and 14% higher than the rural soils.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 78
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Soils contaminated with organic chemicals are now widespread in industrialized and developing countries, and the risk assessment and remediation of such contaminated sites is a priority. However, containment and remediation strategies are complicated in many cases by the range of contaminants present and the historical nature of the contamination. Research has increased our understanding of the behaviour of organic contaminants in soil and the factors that control their behaviour. There is a fundamental need to understand and, where possible, quantify the bioavailable fraction as well as the total concentration of contaminant present in soil: the bioavailable fraction is key to toxicity or biodegradation. To quantify these fractions, a large number of techniques have been employed, ranging from organic and aqueous based solvent extractions to the use of biota. Many studies have been carried out investigating the use of chemical techniques to describe bioavailability, which could be used in the assessment and remediation of contaminated land. The aim of this review is to consider the behaviour of organic contaminants in soil, highlighting issues of bioavailability, and then to discuss the relevance of the various methods for assessing risk and potential remediation of organic contaminants in soil.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 79
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. A number of organic farms in Flanders were sampled to investigate the general phosphorus (P) status and degree of P saturation (Psat) of the soils. Where possible, the soil P status was compared to that in conventional agriculture and related to farm characteristics: agricultural land use, soil texture, fertilization intensity and time since conversion. Generally, the P status of the organic farms was high, and similar to that of conventional farms in Flanders, which is due to the restricted time since conversion to organic farming on most farms. The average soil Psat was slightly lower (37%) than the average value for East Flanders (39%) taken over the soil profile to 90 cm. However, a large proportion of the field areas on organic farms still had a Psat greater than 30% (critical Psat value), which may be an indication that P saturation will continue to be a problem for these farms.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 80
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Application of organic residues to soil is generally assumed to improve soil tilth. Only few studies have reported the long-term effects on the more subtle aspects of soil porosity, and no reports have considered the potential effects of organic amendments on the pore system in the subsoil. We sampled undisturbed soil cores (100 cm3 and 6280 cm3) using metal cylinders in differently fertilized plots in the long-term field experiment at Askov Experimental Station, Denmark. We selected the 0–60 cm soil layer of plots dressed for a century with either mineral fertilizers (labelled NPK) or animal manure (labelled AM) and unfertilized plots (UNF) as a reference. Both fertilization treatments were studied at two levels of nutrient application: ‘normal’ (labelled ‘1’) and 1.5 times ‘normal’ (labelled ‘1½’). Water retention, air permeability and air diffusivity were measured on the small cores, and we used the large cores for measuring near-saturated and saturated hydraulic conductivity. In the plough layer, the AM and NPK soils displayed identical pore volumes in size fractions that were larger as well as smaller than 30 μm, while the UNF soil had a significantly smaller volume of pores 〈 30 μm. No clear trends were found in treatment effects on pore organization as calculated from air diffusivity and air permeability measurements. No significant differences in hydraulic conductivity were found in the plough layer. For the subsoil below ploughing depth, significantly larger macropore volumes and near-saturated hydraulic conductivities were found for soil of plots receiving the larger (‘1½’) amount of nutrients compared with the ‘normally’ dressed soil. This effect was independent of fertilization system (AM or NPK). We attribute the larger volume of macropores to the improved root growth conditions in the soil with the higher nutrient level. We conclude that addition of animal manure at rates realistic in agriculture has only a modest effect on soil pore characteristics of the plough layer soil compared with the use of mineral fertilizers. For the subsoil below ploughing depth, a high level of nutrient application may increase soil macroporosity and near-saturated hydraulic conductivity, but the origin of nutrients is of no significance.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 81
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. A daily multi-layered water balance (DAMUWAB) approach has been formulated with modest input data on daily climatic records, slope gradient, physical soil properties and basic crop characteristics, for predicting the water and oxygen availability in freely drained soils of semiarid as well as subhumid tropical cropping systems. In this study, a simple one-dimensional root extension model is coupled to a water-uptake model that differentiates the uptake capacity of roots according to their depth. It has an intermediate level of detail between functional, 10-day period single-layered water balance (DESIWAB) approaches for land evaluation purposes, and the descriptive, daily water balances used in many crop growth models. Modelling capacity, functionality and expandability of DAMUWAB surpass the performance of DESIWAB. Water and oxygen shortages occurring in each compartment were found to limit water uptake and transpiration. Sensitivity analysis and comparison of DAMLWAB with the worldwide operational DESIWAB approach proved successful for model validation in the tropics and subtropics.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 82
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. A study was conducted to compare the performance of the PR1 capacitance probe (Delta-T Devices) in measuring soil volumetric moisture content (θ) with two established standard methods: the neutron probe (Didcot Instruments) and the gravimetric method. Over a two-year period, the three methods were used to measure θ in glasshouse plots containing crops of either oilseed rape (Brassica napus L.) or bambara groundnut (Vigna subterranea L.). The PR1 probe gave variable performance depending on the depth and soil profile where the measurements were made. In most cases, the PR1 probe significantly overestimated θ. In some cases, it significantly underestimated θ or gave similar values to the other methods. Despite this frequent overestimation of θ, the PR1 probe adequately registered the relative changes in θ Its measurements were linearly and positively related to those of the gravimetric and neutron-probe methods. However, the regression lines significantly deviated from the 1:l line. This paper discusses the possible reasons for the unsatisfactory performance of the PR1 probe and the practical problems associated with the installation of its access tubes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 83
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Nitrate leaching from crop rotations supporting organic grain production was investigated from 1997 to 2000 in a field experiment at three locations in Denmark on different soil types. Three experimental factors were included in the experiment in a factorial design: (1) proportion of N2-fixing crops in the rotation (crop rotation), (2) catch crop (with and without), and (3) manure (with and without). Three, four-course rotations were compared, two at each location. The nitrate leaching was measured using ceramic suction cells. Leaching losses from the crop rotation with grass–clover green manure and without catch crops were 104, 54 and 35 kg N ha−1 yr−1 on the coarse sand, the loamy sand, and the sandy loam, respectively. There was no effect of manure application or time of ploughing-in the grass–clover green manure crop on the accumulated nitrate leaching from the entire rotation. Catch crops reduced nitrate leaching significantly, by 30–38%, on the sandy soils. At all locations catch crops reduced the annual averaged nitrate concentration to meet drinking water quality standards in the crop rotation with green manure. On the coarse sand there was a time lag between the onset of drainage and the start of N-uptake by the catch crop.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 84
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Soil organic carbon stocks to 1 m for Brazil, calculated using an updated Soil and Terrain (SOTER) database and simulation of phenoforms, are 65.9–67.5 Pg C, of which 65% is in the Amazonian region of Brazil. Other researchers have obtained similar gross results, despite very different spatial patterns mapped due to use of different methods.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 85
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. The effects of rice-straw management (incorporation, burning or removal) on soil organic carbon content and physical and hydraulic properties were determined after five years of rice–wheat cropping in a sandy loam soil in northwest India. Soil organic carbon content was greater with straw incorporation and straw burning than with straw removal, and aggregation status, total porosity, pore-size distribution, bulk density, dispersion ratio and soil strength were correspondingly improved. The treatment effects were confined mainly to the 0–5 cm depth. Water retention was less with straw burning than straw removal, owing to increased water repellency of the soil surfaces. Cumulative infiltration and its rate after five hours were greater with straw incorporation than straw burning or removal. Air entry values were unaffected by straw management; however, the values were greater after rice harvest than after wheat harvest.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 86
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. A field study was conducted to assess the effect of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP), applied at a rate of 1 kg ha−1, on nitrous oxide (N2O) emissions, forage production and N extraction from a grassland soil after cattle slurry applications in autumn and spring. Nitrous oxide emissions were measured daily or weekly using the closed chamber technique. DMPP efficiency after slurry application was lower in spring (16.7 °C mean soil temperature) than in autumn (11.4 °C mean soil temperature). Thus, DMPP was able to maintain soil mineral N in the ammonium form for 22 days and reduce cumulative N2O emissions by 69% in autumn, while in spring its effect on soil mineral N lasted for 7–14 days, reducing cumulative N2O losses by 48%. Furthermore, application of DMPP after slurry did not decrease biomass yield or N uptake.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 87
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 88
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. The effects of nitrogen fertilizer and tillage systems on soil organic carbon (SOC) storage have been tested in many field experiments worldwide. The published results of this research are here compiled for evaluation of the impact of management practices on carbon sequestration. Paired data from 137 sites with varying nitrogen rates and 161 sites with contrasting tillage systems were included. Nitrogen fertilizer increased SOC but only when crop residues were returned to the soil; a multiple regression model accounted for just over half the variance (R2=0.56, P=0.001). The model included as independent variables: cumulative nitrogen fertilizer rate; rainfall; temperature; soil texture; and a cropping intensity index, calculated as a combination of the number of crops per year and percentage of corn in the rotation. Carbon sequestration increased as more nitrogen was applied to the system, and as rainfall or cropping intensity increased. At sites with higher mean temperatures and also in fine textured soils, carbon sequestration decreased. When the carbon costs of production, transportation and application of fertilizer are subtracted from the carbon sequestration predicted by the model, it appears that nitrogen fertilizer-use in tropical regions results in no additional carbon sequestration, whereas in temperate climates, it appears to promote net carbon sequestration. No differences in SOC were found between reduced till (chisel, disc, and sweep till) and no-till, whereas conventional tillage (mouldboard plough, disc plough) was associated with less SOC. The accumulation of SOC under conservation tillage (reduced and no till) was an S-shape time dependent process, which reached a steady state after 25–30 years, but this relationship only accounted for 26% of the variance. Averaging out SOC differences in all the experiments under conservation tillage, there was an increase of 2.1 t C ha−1 over ploughing. However, when only those cases that had apparently reached equilibrium were included (all no till vs. conventional tillage comparisons from temperate regions), mean SOC increased by approximately 12 t C ha−1. This estimate is larger than others previously reported. Carbon sequestration under conservation tillage was not significantly related to climate, soil texture or rotation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 89
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Over the last three decades there has been a great increase in the production of waste from urban, industrial and agricultural activity that could be recycled as a source of plant nutrients, and used to enhance soil quality. The use of these materials could partially offset the need for mineral fertilizers, giving both economic and environmental benefits. An incubation experiment was carried out using different organic waste materials applied to a Cambic Arenosol. Air-dried soil was mixed with increasing amounts of composted solid municipal waste, secondary pulp-mill sludge, hornmeal, poultry manure, solid phase from pig slurry, and composted pig manure, resulting in applications equivalent to 0, 40, 80, 120, 160 and 200 kg ha−1 of Kjeldahl nitrogen. The samples were incubated for 244 days under a controlled environment of 24 °C and 60% water holding capacity of the soil. The increasing amounts of waste applied always led to a greater amount of potentially available nitrogen present in the soil/waste mixture. Based on the proportion of their active N fraction, wastes were ranked: poultry manure〉hornmeal〉solid phase from pig slurry〉composted pig manure〉secondary pulp-mill sludge〉composted municipal solid waste. The results were well described by a one-pool exponential mineralization model, and mineral N formation was proportional to the quantity of waste applied. Of the wastes tested, those from animal sources showed greater nitrogen mineralisation. Nitrification was rapid, and concentrations of ammonium nitrogen remained relatively small.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 90
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Knowledge of the stocks and the potential range of soil organic carbon (SOC) in various land–soil combinations is an important precursor to policies aimed at linking, for example, management of SOC to greenhouse gas emission controls. To investigate the factors controlling the percentage of SOC (%SOC) of soils in England and Wales, we made a multiple regression analysis of data for the 2448 arable and ley-arable sites in the 1980 England and Wales National Soil Inventory (NSI). Clay content, average annual precipitation and depth of topsoil explained 25.5% of the variation in %SOC, when calcareous and peaty soils and those susceptible to flooding were excluded. Using ‘robust’ statistics, ‘indicative SOC management ranges’ were estimated for different physiotopes, that is, landscape units for which the environmental factors governing %SOC are similar, namely soil clay content and precipitation. These ranges describe the expected %SOC range for an arable soil in a given physiotope. They have potential to support approximate targets for the %SOC of arable soils and for estimating upper and lower limits for sequestered soil carbon in arable systems.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 91
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Hydraulic properties of soils after rice cropping are generally unfavourable for wheat cultivation. Poor drainage, delayed planting and oxygen stress in the root zone may adversely affect the wheat crop after lowland rice cultivation. We studied long-term effects of lantana (Lantana spp. L.) residue additions at 10, 20 and 30 t ha−1 yr−1 (fresh biomass) on physical properties of a silty clay loam soil under rice–wheat cropping in northwest India. At the end of ten cropping cycles, soil water retention, infiltration rate, saturated hydraulic conductivity and drying rate of soil increased significantly with lantana additions. The available water capacity (AWC), on volume basis, declined at rice harvest (from 22.0 to 18.8–20.9%), but increased at wheat harvest (from 12.9 to 13.4–15.0%) after lantana treatment. The volumes of water transmission (〉50 μm) and storage pores (0.5–50 μm) were greater, while the volume of residual pores (〈0.5 μm) was smaller in lantana-treated plots than in controls at both rice and wheat harvest. Infiltration rate in the lantana-treated soil was 1.6–7.9 times that of the control (61 mm d−1) at rice harvest, and 2–4.1 times that of the control (1879 mm d−1) at wheat harvest. Thus lantana addition improved soil hydraulic properties to the benefit of the wheat crop in a rice–wheat cropping sequence.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 92
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 93
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Terrestrial ecosystem risk assessment remains in its infancy by comparison with the aquatic discipline, yet it is advancing quickly in response to increasing concerns surrounding soil quality and the sustainable use of soil. Several international frameworks have been developed during the last decade to aid decision-makers as the need for scientifically derived tools for determining ecological risk from land contamination has been recognized. From the regulatory viewpoint, the priority is establishing what to protect in order to prevent ecological harm. This is a complex issue requiring clear objectives in a risk assessment context. The most important factor in assessing ecological harm is whether or not ecosystem function is altered as a result of land contamination and, if it is, judging the significance. A consensus is developing that ecological risk assessment should aim to protect populations rather than individuals. This paper critically reviews recent developments in risk assessment for terrestrial ecosystems and land contamination in the UK, with emphasis on deriving a measure of ecological harm to assess ecosystem function. We seek to further justify the use of earthworms as a favoured indicator species for protecting ecological function. Guidance on how to measure harm in relation to ecological function is, however, still lacking.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 94
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Effective use and recycling of manures together with occasional and judicious use of supplementary fertilizing materials forms the basis for management of phosphorus (P) and potassium (K) within organic farming systems. Replicated field trials were established at three sites across the UK to compare the supply of P and K to grass–clover swards cut for silage from a range of fertilizing materials, and to assess the usefulness of routine soil tests for P and K in organic farming systems. None of the fertilizing materials (farmyard manure, rock phosphate, Kali vinasse, volcanic tuff) significantly increased silage yields, nor was P offtake increased. However, farmyard manure and Kali vinasse proved effective sources of K to grass and clover in the short to medium term. Available P (measured as Olsen-P) showed no clear relationship with crop P offtake in these trials. In contrast, available K (measured by ammonium nitrate extraction) proved a useful measurement to predict K availability to crops and support K management decisions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 95
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. We investigated whether an insoluble polyacrylate polymer could be used to improve the quality of a copper-contaminated soil. Growth of annual medic (Medicago polymorpha L.) was stimulated in the polymer-amended soil, such that total biomass produced was three times that of plants from unamended soil. Roots of plants cultivated in the polymer-amended soil had a concentration of copper that was 73% of that in plants from the unamended soil. Biological N2 fixation was enhanced in the polymer-amended soil. Soil enzymatic activities at the end of the experiment were correlated with plant growth and copper concentration of plants grown in soils with different levels of copper, which were achieved by mixing the contaminated soil with varying proportions of a soil of low copper content. Shoot dry weight was positively correlated with acid phosphatase, β-glucosidase, β-galactosidase and urease, whereas copper concentration in the roots of the annual medic was negatively correlated with acid phosphatase, β-galactosidase, cellulase and urease. The results are consistent with soil remediation by the polyacrylate polymer. Soil quality as inferred from plant growth, biological N2 fixation and soil enzymatic activities improved as a result of the remediation process.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 96
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. In Australia, stubble burning and tillage are two of the major processes responsible for the decline of soil organic carbon concentration in cropped soils, and the resulting soil degradation. However, the relative importance of these two practices in influencing the soil organic carbon concentration and the long-term impact on soil quality and productivity are not clear. The effects of stubble burning as practised by farmers in southeastern Australia were evaluated in two field trials, one of 19 years duration, the other of 5 years. Conventional tillage (three tillage passes) led to greater loss of soil organic carbon than stubble burning. Loss of total soil organic carbon attributed to stubble burning in the 0–10 cm layer was estimated to be 1.75 t C ha−1 over the period of the 19-year trial, equivalent to 29% of that lost due to tillage. In the 5-year trial, no change in soil organic carbon due to stubble burning was detectable. Changes in soil quality associated with stubble burning detected in the longer trial included a reduction in macro-aggregate stability, and increases in pH and exchangeable K+. Only the latter two were detected in the shorter trial. A higher mean wheat yield (average 0.15 t ha−1) following stubble burning was observed in the 19-year trial but not in the 5-year trial. Research to monitor the longer term effects of stubble burning is needed, and to identify conditions where loss of soil organic carbon is minimized.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 97
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract In Galicia (northwest Spain) the application of organic wastes to agricultural land is a common practice, which may increase total and bioavailable metal contents in the soil. In this study, total metal concentrations were determined in acid soils under different use (pasture, cropland, woodland) in an agricultural area where agro-industrial sludges are frequently recycled as manure. The aim was to establish baseline metal levels which could be used to determine the capacity of soils to absorb organic wastes. The estimation of baseline metal concentrations was carried out by two methods, one based on the analysis of means and geometric deviations, and another based on a modal analysis. Results suggested that the modal analysis procedure might be preferable when analysing data sets with a heterogeneous frequency distribution. In general, there was no significant difference in total metal concentrations when comparing soils from different land uses. Baseline levels for each metal indicated that all soils were suitable for organic waste application under current European Union (EU) legislation. From 2015, more restrictive metal limit values have been proposed by the EU, potentially preventing the addition of metal-containing wastes to pasture, cropland and woodland soils. The dissolved metal values in each soil were also estimated by empirical equations relating total metal concentrations, pH and organic matter content. Results showed that only the pasture soils would be suitable for organic waste disposal under the proposed EU metal limits for 2015, due to liming and substantial organic matter content. Total metal concentrations were insufficient to discriminate environmental risk in acid soils of different land use. The determination of baseline levels in reference areas and the estimation of soil metal bioavailability are suggested to define permissible values in the developing legislation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 98
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Despite considerable investment, some UK bathing waters fail to comply with mandatory standards as defined by the EU Bathing Water Directive (76/160/EEC). Continued non-compliance has been associated with diffuse sources of faecal indicator organism (FIO) contamination, in particular those deriving from agricultural land. This paper examines concentrations of FIOs in surface, subsurface and instream water samples at field sites considered to pose a high potential risk of FIO contamination. Quality of samples was compared with FIO standards for bathing water compliance in the UK. FIO concentrations exceeding mandatory and guideline standards were recorded frequently at all sites. In freely draining soils, FIO mobilization by rainfall was predominantly via subsurface flow, with occasional surface water flow linked to intensive rainfall events. In slowly permeable soils, surface mobilization of FIOs predominated, with the occurrence of limited subsurface samples linked to seasonal desiccation cracking within the soil, and to intense rainfall events. Watercourse FIO concentrations were significantly increased as the stream passed-by fields with freely draining soils. The data imply a generally higher risk of FIO transfer from freely draining soils and occasional increased risk from less permeable soils due to temporal changes in soil structure and rainfall intensity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 99
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Nutrient losses from arable land are important contributors to eutrophication of surface waters, and phosphorus (P) and nitrogen (N) usually act together to regulate production of Cyanobacteria. Concentrations and losses of both nutrients in drainage water from pipe drains were studied and compared in 15 crop rotations on a clay soil in southwest Sweden. Special emphasis was placed on P and it was possible to evaluate critical components of the crop rotations by flow-proportional water sampling. Total P concentrations in drainage water were generally small (0.04–0.18 mg L−1), but during two wetter years out of six, high P concentrations were measured following certain management practices, including ploughing-in lucerne (Medicago sativa L.) and fertilizing in advance without incorporation into the soil to meet the needs of several subsequent crops. This resulted in average flow-weighted concentrations of total P between 0.3 and 0.7 mg L−1. In crop rotations containing green manures, green fallow or leguminous leys, there was also a risk for increased P losses after these crops were ploughed in. The losses increased in the order: cash crops 〈 dairy with grass 〈 dairy with lucerne 〈 monoculture with barley 〈 organic farming with cattle slurry 〈 stockless organic farming with green manure. P balances varied between −9 and +8 kg P ha−1 and N balances between +4 and +35 kg N ha−1. The balances were not related to actual leaching losses. Phosphorus losses in drainage from set-aside were 67–82% of those from cash crops grown in ploughed and P-fertilized soil at the same site, indicating a high background P loss from this clay soil.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 100
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 21 (2005), S. 0 
    ISSN: 1475-2743
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. Changes in surface soil properties of a savanna Alfisol under cultivation with applications of manure and inorganic NPK fertilizer were evaluated after 45 years of annual cropping. Soils from treatments with fertilizer only, fertilizer in combination with farmyard manure (FYM) at both high and low rates were compared to soil from a control receiving neither fertilizer nor manure. The high rate of FYM and fertilizer significantly improved soil aggregation, increased C, N and P status, while reducing soil penetration resistance. The results showed that there is a need to use both manure and inorganic fertilizer to maintain soil fertility in savanna soils under continuous cultivation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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