ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Springer  (16)
  • 2000-2004  (2)
  • 1995-1999  (12)
  • 1975-1979  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Folk theorems on transmission access: Proofs and counterexamples (1996)
    Springer
    Journal of regulatory economics 10 (1996), S. 5-23 
    Details
    ISSN: 1573-0468
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract Nodal prices, congestion revenues, transmission capacity rights, and compensation for wire ownership are key concepts used to formulate claims about proposals to organize competitive and open transmission access. Underlying those claims are implicit assertions (folk theorems) concerning the regulation of transmission access, the determination of power flows, properties of economic dispatch, and the operations of competitive nodal markets for power. The paper has two objectives. We first formulate these folk theorems as explicit mathematical assertions. We then prove that some of these assertions are true, and we present counterexamples to other assertions. The counterexamples are interesting because they negate plausible propositions, including: (1) uncongested lines do not receive congestion rents (defined through node price differences); (2) nodal prices clear markets for power only if the allocation is efficient; (3) in an efficient allocation power can only flow from nodes with lower prices to nodes with higher prices; (4) strengthening transmission lines or building additional lines increases transmission capacity; (5) transmission capacity rights are compatible with any economically efficient dispatch.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00133356
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Long-term variation in the effect of lizards on spider density is linked to rainfall (1995)
    Springer
    Oecologia 103 (1995), S. 133-139 
    Details
    ISSN: 1432-1939
    Keywords: Rainfall ; Climate ; Predation ; Spiders ; Lizards
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The objective of this study was to ascertain whether the impact of lizards on spiders varies temporally, and if so, whether this variability is related to rainfall. We compared annual censuses of orb-spider populations on 24 islands with diurnal lizards present, and on 20 islands with diurnal lizards absent, to rainfall over a 10-year period. A strong positive correlation (Pearson r=0.877) was found between mean spider density on nolizard islands and the number of days of rain that occurred 2 months prior to spider censuses; correlation coefficients declined with longer and shorter time periods prior to censuses. Correlation coefficients between mean spider density on lizard islands and rainfall showed a similar pattern but were generally lower than those for no-lizard islands. The strength of the impact of lizards on spiders, measured as the ratio of mean spider density on no-lizard islands to mean spider density on lizard islands, varied considerably and was positively correlated with rainfall; the correlation was highest with number of rain days 6 months prior to spider censuses (r=0.741). Repeated-measures analysis of variance on the time series of spider densities showed that the lizard factor (present versus absent) varied significantly among years. Split-plot ANOVA with rainfall as a covariate indicated that spider density and the impact of lizards on spider density were both significantly correlated with rainfall. We discuss several hypotheses on the causal mechanisms that integrate abiotic and biotic factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00329072
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Intracellular appearance of nitrite and nitrate in nitrogen-starved cells of Ankistrodesmus braunii (1976)
    Springer
    Planta 129 (1976), S. 175-181 
    Details
    ISSN: 1432-2048
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The occurrence of heterotrophic nitrification in nitrogen-starved cells of Ankistrodesmus braunii was confirmed. The levels of nitrate and nitrite were measured over a period of four weeks. The validity of quantitative determinations in the presence of highly active nitrate and nitrite reductases is discussed. Whereas free hydroxylamine as an intermediate could not be detected, increased hydroxylamine oxidase activity was found in nitrogen-starved cultures. Nitrite reductase and hydroxylamine oxidase can be assigned to particles by sucrose density gradient centrifugation. The possible involvement of microbodies, which were found to be present in Ankistrodesmus, in metabolic processes during nitrogen starvation is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00390025
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The quantum to classical crossover for a weak link capacitor (1995)
    Springer
    Journal of low temperature physics 101 (1995), S. 1037-1054 
    Details
    ISSN: 1573-7357
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We consider a model weak link, an ultra-small capacitor subject to tunnelling, to ohmic dissipation and fed with an external displacement current. The framework we employ is the new approach of quantum state diffusion, which treats individual open quantum systems as well as being able to generate the conventional ensemble averages. We show how evidence for archetypal quantum behaviour (coherent oscillations) and archetypal classical behaviour (chaos) arises, for weak links whose parameters are related by a rather modest scaling. Interestingly, the quantum behaviour can arise for a weak link with intrinsic parameter values such that it could exhibit chaos, if it were a purely classical device.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00754523
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Echo-Planar Magnetic Resonance Imaging to Assess Water Volume in the Distal Small Bowel (1995)
    Springer
    Pharmaceutical research 12 (1995), S. 1134-1139 
    Details
    ISSN: 1573-904X
    Keywords: mannitol ; small intestinal transit ; echo-planar magnetic resonance imaging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. Assessment of fluid volumes and flow through the small intestine has in the past only been possible by means of invasive intubation studies on human volunteers. Intubation very likely disturbs gut motility and stimulates secretion. Methods. The aim of this study was to utilise the new technique of echo-planar magnetic resonance imaging in order to non-invasively visualise the changing volume of water in the small intestinal lumen. 200mls of test solution was ingested and water volume assessed using a multi-slice scanning technique on 3 separate days. The solutions were pure water, pure water plus 2.264 or l0g of mannitol. These were taken on separate days by 8 healthy male volunteers. Regions of interest were constructed in the area of the lower pelvis excluding retroperitoneal structures. Results. The water content of the lower small intestine did not change significantly over the 4 hours after the control solution. By contrast after both mannitol solutions there was an increase in the amount of water in the distal intestine as assessed by the area under the curve of the volume time profile (Control 51 ml.h (SD ±47); mannitol 2.264g/200ml 72ml.h (SD ±57); 10g/200ml mannitol 115ml.h (SD ±56)). Page's L Trend test showed that the trend for the volume to increase with increasing mannitol concentration to be statistically significant at the 1% level (L= 108). Conclusions. The study highlights the potential of echo-planar magnetic resonance imaging to visualise changes in gastrointestinal physiology in a non-invasive manner.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016251624220
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Faculty Responsibilities in Dealing with Collegiate Cheating: A Student Development Perspective (1997)
    Springer
    Teaching business ethics 1 (1997), S. 117-130 
    Details
    ISSN: 1573-1944
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Economics
    Notes: Abstract Recent research has demonstrated that business students have more tolerant attitudes toward cheating (Roig and Ballew, 1994), tend to believe they need unethical beliefs in order to complete their degrees (Lane and Schaupp, 1989), and are more likely to cheat than non-business students (Baird, 1980; McCabe and Trevino, 1995). Given the importance of this issue, this paper discusses the responsibilities of faculty members in dealing with collegiate cheating. A student development perspective (Kibler, 1993; Sanford, 1966) is used to articulate these responsibilities. Three other perspectives are discussed with respect to each viewpoint's limitations to students' development. In addition, based on empirical, theoretical, and experimental information, strategies for managing classroom cheating are offered within the framework of the student development perspective. Special attention is paid to issues relevant to business students and faculty throughout the paper.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009728100939
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    In situ detection of heavy metal substituted chlorophylls in water plants (1998)
    Springer
    Photosynthesis research 58 (1998), S. 123-133 
    Details
    ISSN: 1573-5079
    Keywords: antenna pigments ; copper ; fluorescence microscopy ; fluorimetry ; spectroscopy ; zinc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The in vivo substitution of magnesium, the central atom of chlorophyll, by heavy metals (mercury, copper, cadmium, nickel, zinc, lead) leads to a breakdown in photosynthesis and is an important damage mechanism in heavy metal-stressed plants. In this study, a number of methods are presented for the efficient in situ detection of this substitution (i.e. in whole plants or in chloroplasts). While macroscopic observations point to the formation of heavy metal chlorophylls at higher concentrations, fluorescence microscopy enables the detection of this reaction at very low substitution rates. Therefore, the course of the reaction can be followed by continuously measuring the fluorescence of whole plants. Furthermore absorbance spectroscopy of whole cells or isolated chloroplasts also enables the in situ detection of heavy metal chlorophylls. These methods provide practicable approaches in detecting the formation of these compounds in situ, avoiding artefacts that might occur using extraction methods based on polar solvents. In addition to the new methods for in situ detection, an extreme heterogeneity in the reaction of cells in the same tissue upon heavy metal stress was observed: while some cells are already disintegrating, others still show normal fluorescence and photosynthetic activity. Measurements of fluorescence kinetics gave a further hint that in high light intensity a substitution of Mg by heavy metals might take place specifically in PS II reaction centres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006132608181
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Ethical Business and Investment: A Model for Business and Society (2000)
    Springer
    Journal of business ethics 27 (2000), S. 149-160 
    Details
    ISSN: 1573-0697
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Economics
    Notes: Abstract Two key questions lie at the heart of the business challenge for business ethics: is it possible for business and investors to do well while doing good; and if so, how can this be achieved? This paper adopts an international investment perspective to address these questions. It demonstrates that it is possible for business and investors to achieve a triple bottom line of environmental, social and financial performance. A new integrated model of Ethical Business including an Ethical Scorecard performance measurement technology is presented based on international ethical investment criteria and case studies of businesses rated highly by ethical investors. Ethical Performance Scores are presented for these businesses and New Zealand business. Examples from New Zealand are presented to illustrate the Ethical Scorecard and ethical business practice. The model and scoring system provide a basis for international benchmarking of ethical business to assist investors, managers and researchers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006445915026
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Learning from the Literature on Collegiate Cheating: A Review of Empirical Research (1998)
    Springer
    Journal of business ethics 17 (1998), S. 683-700 
    Details
    ISSN: 1573-0697
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Economics
    Notes: Abstract The role demographic, personality, and situational factors play in the ethical decision making process has received a significant amount of attention (Ford and Richardson, 1994). However, the empirical research on students' decisions to engage in collegiate cheating has not been included in this literature. This paper reviews the last 25 years of empirical research on collegiate cheating. The individual/situational factor typology from Ford and Richardson's review (1994) is used to compare the two literatures. In addition, issues pertaining to the quantification of academic dishonesty, the perception that cheating is increasing, and methodological considerations are addressed in this review.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1017903001888
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Regional Differences in Quinine Absorption from the Undisturbed Human Colon Assessed Using a Timed Release Delivery System (1999)
    Springer
    Pharmaceutical research 16 (1999), S. 1087-1092 
    Details
    ISSN: 1573-904X
    Keywords: transcellular ; paracellular ; absorption ; gastrointestinal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. To investigate the regional absorption characteristics of the distal gut using two markers of permeability, quinine (a transcellular probe) and 51CrEDTA (a paracellular probe). Methods. The permeability markers were delivered to the undisturbed gastrointestinal tract in 39 healthy volunteers using an oral timed-release delivery vehicle which allowed pulsed release within a particular site of the gut. Site of release was identified using gamma scintigraphy. Absorption of quinine and 5lCrEDTA was assessed by measuring the percent excretion in the urine using HPLC and gamma counting respectively. Serial plasma samples allowed time-concentration curves for quinine to be plotted. Results. There was a significant trend for diminished absorption with more distal delivery of the transcellular probe, quinine, which was: 6.26 ± 0.87% (small intestine, n = 10); 4.65 ± 0.93% (ascending colon, n = 16); and 2.59 ± 0.52% (transverse colon, n = 10) of the ingested dose excreted respectively (p 〈 0.001). No such gradient was seen with the paracellular marker, 5lCrEDTA. Conclusions. These results suggest that delayed release formuations should aim for release in the distal small bowel and proximal colon if absorption is to be miximised. Absorption by the transcellular route diminishes in the more distal colon, a fact which has implications for delayed or sustained release formulations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018948102778
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...