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  • Blackwell Publishing Ltd  (24.939)
  • Santiago de Chile
  • Santiago de Chile: Universidad de Chile, Departamento de Economía
  • La Habana
  • 2020-2023  (8)
  • 1975-1979  (15.626)
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  • 1
    Publikationsdatum: 2022-09-27
    Beschreibung: Little research attention has been given to validating clusters obtained from the groundwater geochemistry of the waterworks' capture zone with a prevailing lake‐groundwater exchange. To address this knowledge gap, we proposed a new scheme whereby Gaussian finite mixture modeling (GFMM) and Spike‐and‐Slab Bayesian (SSB) algorithms were utilized to cluster the groundwater geochemistry while quantifying the probability of the resulting cluster membership against each other. We applied GFMM and SSB to 13 geochemical parameters collected during different sampling periods at 13 observation points across the Barnim Highlands plateau located in the northeast of Berlin, Germany; this included 10 observation wells, two lakes, and a gallery of drinking production wells. The cluster analysis of GFMM yielded nine clusters, either with a probability ≥0.8, while the SSB produced three hierarchical clusters with a probability of cluster membership varying from 〈0.2 to 〉0.8. The findings demonstrated that the clustering results of GFMM were in good agreement with the classification as per the principal component analysis and Piper diagram. By superimposing the parameter clustering onto the observation clustering, we could identify discrepancies that exist among the parameters of a certain cluster. This enables the identification of different factors that may control the geochemistry of a certain cluster, although parameters of that cluster share a strong similarity. The GFMM results have shown that from 2002, there has been active groundwater inflow from the lakes towards the capture zone. This means that it is necessary to adopt appropriate measures to reverse the inflow towards the lakes.
    Beschreibung: Article impact statement: The probability of cluster membership quantified using an algorithm should be validated against another probabilistic‐based classifier.
    Beschreibung: Federal Ministry of Education and Research http://dx.doi.org/10.13039/501100002347
    Schlagwort(e): ddc:551.9 ; ddc:551.49
    Sprache: Englisch
    Materialart: doc-type:article
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  • 2
    Publikationsdatum: 2022-10-01
    Beschreibung: Copper (Cu) is an essential element for plants and microorganisms and at larger concentrations a toxic pollutant. A number of factors controlling Cu dynamics have been reported, but information on quantitative relationships is scarce. We aimed to (i) quantitatively describe and predict soil Cu concentrations (CuAR) in aqua regia considering site‐specific effects and effects of pH, soil organic carbon (SOC) and cation exchange capacity (CEC), and (ii) study the suitability of mixed‐effects modelling and rule‐based models for the analysis of long‐term soil monitoring data. Thirteen uncontaminated long‐term monitoring soil profiles in southern Germany were analysed. Since there was no measurable trend of increasing CuAR concentrations with time in the respective depth ranges of the sites, data from different sampling dates were combined and horizon‐specific regression analyses including model simplifications were carried out for 10 horizons. Fixed‐ and mixed‐effects models with the site as a random effect were useful for the different horizons and significant contributions (either of main effects or interactions) of SOC, CEC and pH were present for 9, 8 and 7 horizons, respectively. Horizon‐specific rule‐based cubist models described the CuAR data similarly well. Validations of cubist models and mixed‐effects models for the CuAR concentrations in A horizons were successful for the given population after random splitting into calibration and validation samples, but not after independent validations with random splitting according to sites. Overall, site, CEC, SOC and pH provide important information for a description of CuAR concentrations using the different regression approaches. Highlights: Information on quantitative relationships for factors controlling Cu dynamics is scarce. Site, CEC, SOC and pH provide important information for a description of Cu concentrations. Validations of cubist models and mixed‐effects models for A horizons were successful for a closed population of sites.
    Beschreibung: Bavarian State Ministry of the Environment and Consumer Protection http://dx.doi.org/10.13039/501100010219
    Beschreibung: Ministry of Agriculture and Environment Mecklenburg‐Western Pomerania
    Schlagwort(e): ddc:631.4
    Sprache: Englisch
    Materialart: doc-type:article
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  • 3
    Publikationsdatum: 2022-10-04
    Beschreibung: Soil aeration is a critical factor for oxygen‐limited subsoil processes, as transport by diffusion and advection is restricted by the long distance to the free atmosphere. Oxygen transport into the soil matrix is highly dependent on its connectivity to larger pore channels like earthworm and root colonised biopores. Here we hypothesize that the soil matrix around biopores represents different connectivity depending on biopore genesis and actual coloniser. We analysed the soil pore system of undisturbed soil core samples around biopores generated or colonised by roots and earthworms and compared them with the pore system of soil, not in the immediacy of a biopore. Oxygen partial pressure profiles and gas relative diffusion was measured in the rhizosphere and drilosphere from the biopore wall into the bulk soil with microelectrodes. The measurements were linked with structural features such as porosity and connectivity obtained from X‐ray tomography and image analysis. Aeration was enhanced in the soil matrix surrounding biopores in comparison to the bulk soil, shown by higher oxygen concentrations and higher relative diffusion coefficients. Biopores colonised by roots presented more connected lateral pores than earthworm colonised ones, which resulted in enhanced aeration of the rhizosphere compared to the drilosphere. This has influenced biotic processes (microbial turnover/mineralization or root respiration) at biopore interfaces and highlights the importance of microstructural features for soil processes and their dependency on the biopore's coloniser.
    Beschreibung: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659
    Schlagwort(e): ddc:631.4
    Sprache: Englisch
    Materialart: doc-type:article
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  • 4
    Publikationsdatum: 2022-07-26
    Beschreibung: Application of farmyard manure (FYM) is common practice to improve physical and chemical properties of arable soil and crop yields. However, studies on effects of FYM application mainly focussed on topsoils, whereas subsoils have rarely been addressed so far. We, therefore, investigated the effects of 36‐year FYM application with different rates of annual organic carbon (OC) addition (0, 469, 938 and 1875 g C m−2 a−1) on OC contents of a Chernozem in 0–30 cm (topsoil) and 35–45 cm (subsoil) depth. We also investigated its effects on soil structure and hydraulic properties in subsoil. X‐ray computed tomography was used to analyse the response of the subsoil macropore system (≥19 μm) and the distribution of particulate organic matter (POM) to different FYM applications, which were related to contents in total OC (TOC) and water‐extractable OC (WEOC). We show that FYM‐C application of 469 g C m−2 a−1 caused increases in TOC and WEOC contents only in the topsoil, whereas rates of ≥938 g C m−2 a−1 were necessary for TOC enrichment also in the subsoil. At this depth, the subdivision of TOC into different OC sources shows that most of the increase was due to fresh POM, likely by the stimulation of root growth and bioturbation. The increase in subsoil TOC went along with increases in macroporosity and macropore connectivity. We neither observed increases in plant‐available water capacity nor in unsaturated hydraulic conductivity. In conclusion, only very high application of FYM over long periods can increase OC content of subsoil at our study site, but this increase is largely based on fresh, easily degradable POM and likely accompanied by high C losses when considering the discrepancy between OC addition rate by FYM and TOC response in soil. Highlights A new image processing procedure to distinguish fresh and decomposed POM. The increase of subsoil C stock based to a large extend on fresh, labile POM. Potential of arable subsoils for long‐term C storage by large FYM application rates is limited. The increase in TOC has no effect on hydraulic properties of the subsoil.
    Beschreibung: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659
    Schlagwort(e): ddc:631.4
    Sprache: Englisch
    Materialart: doc-type:article
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  • 5
    Publikationsdatum: 2022-04-01
    Beschreibung: We present a workflow to estimate geostatistical aquifer parameters from pumping test data using the Python package welltestpy. The procedure of pumping test analysis is exemplified for two data sets from the Horkheimer Insel site and from the Lauswiesen site, Germany. The analysis is based on a semi‐analytical drawdown solution from the upscaling approach Radial Coarse Graining, which enables to infer log‐transmissivity variance and horizontal correlation length, beside mean transmissivity, and storativity, from pumping test data. We estimate these parameters of aquifer heterogeneity from type‐curve analysis and determine their sensitivity. This procedure, implemented in welltestpy, is a template for analyzing any pumping test. It goes beyond the possibilities of standard methods, for example, based on Theis' equation, which are limited to mean transmissivity and storativity. A sensitivity study showed the impact of observation well positions on the parameter estimation quality. The insights of this study help to optimize future test setups for geostatistical aquifer analysis and provides guidance for investigating pumping tests with regard to aquifer statistics using the open‐source software package welltestpy.
    Beschreibung: Article impact statement: We present a workflow to infer parameters of subsurface heterogeneity from pumping test data exemplified at two sites using welltestpy.
    Beschreibung: German Federal Environmental Foundation (DBU) http://dx.doi.org/10.13039/100007636
    Schlagwort(e): ddc:551.49
    Sprache: Englisch
    Materialart: doc-type:article
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  • 6
    Publikationsdatum: 2022-04-01
    Beschreibung: In designed experiments, different sources of variability and an adequate scale of measurement need to be considered, but not all approaches in common usage are equally valid. In order to elucidate the importance of sources of variability and choice of scale, we conducted an experiment where the effects of biochar and slurry applications on soil properties related to soil fertility were studied for different designs: (a) for a field‐scale sampling design with either a model soil (without natural variability) as an internal control or with composited soils, (b) for a design with a focus on amendment variabilities, and (c) for three individual field‐scale designs with true field replication and a combined analysis representative of the population of loess‐derived soils. Three silty loam sites in Germany were sampled and the soil macroaggregates were crushed. For each design, six treatments (0, 0.15 and 0.30 g slurry‐N kg−1 with and without 30 g biochar kg−1) were applied before incubating the units under constant soil moisture conditions for 78 days. CO2 fluxes were monitored and soils were analysed for macroaggregate yields and associated organic carbon (C). Mixed‐effects models were used to describe the effects. For all soil properties, results for the loess sites differed with respect to significant contributions of fixed effects for at least one site, suggesting the need for a general inclusion of different sites. Analysis using a multilevel model allowed generalizations for loess soils to be made and showed that site:slurry:biochar and site:slurry interactions were not negligible for macroaggregate yields. The use of a model soil as an internal control enabled observation of variabilities other than those related to soils or amendments. Experiments incorporating natural variability in soils or amendments resulted in partially different outcomes, indicating the need to include all important sources of variability. Highlights Effects of biochar and slurry applications were studied for different designs and mixed‐effects models were used to describe the effects. Including an internal control allowed observation of, e.g., methodological and analytical variabilities. The results suggested the need for a general inclusion of different sites. Analysis using a multilevel model allowed generalizations for loess soils. The results indicated the need to include all important sources of variability.
    Schlagwort(e): ddc:631.4
    Sprache: Englisch
    Materialart: doc-type:article
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  • 7
    Publikationsdatum: 2022-04-01
    Beschreibung: Temperate forest soils are often considered as an important sink for atmospheric carbon (C), thereby buffering anthropogenic CO2 emissions. However, the effect of tree species composition on the magnitude of this sink is unclear. We resampled a tree species common garden experiment (six sites) a decade after initial sampling to evaluate whether forest floor (FF) and topsoil organic carbon (Corg) and total nitrogen (Nt) stocks changed in dependence of tree species (Norway spruce—Picea abies L., European beech—Fagus sylvatica L., pedunculate oak—Quercus robur L., sycamore maple—Acer pseudoplatanus L., European ash—Fraxinus excelsior L. and small‐leaved lime—Tilia cordata L.). Two groups of species were identified in terms of Corg and Nt distribution: (1) Spruce with high Corg and Nt stocks in the FF developed as a mor humus layer which tended to have smaller Corg and Nt stocks and a wider Corg:Nt ratio in the mineral topsoil, and (2) the broadleaved species, of which ash and maple distinguished most clearly from spruce by very low Corg and Nt stocks in the FF developed as mull humus layer, had greater Corg and Nt stocks, and narrow Corg:Nt ratios in the mineral topsoil. Over 11 years, FF Corg and Nt stocks increased most under spruce, while small decreases in bulk mineral soil (esp. in 0–15 cm and 0–30 cm depth) Corg and Nt stocks dominated irrespective of species. Observed decadal changes were associated with site‐related and tree species‐mediated soil properties in a way that hinted towards short‐term accumulation and mineralisation dynamics of easily available organic substances. We found no indication for Corg stabilisation. However, results indicated increasing Nt stabilisation with increasing biomass of burrowing earthworms, which were highest under ash, lime and maple and lowest under spruce. Highlights We studied if tree species differences in topsoil Corg and Nt stocks substantiate after a decade. The study is unique in its repeated soil sampling in a multisite common garden experiment. Forest floors increased under spruce, but topsoil stocks decreased irrespective of species. Changes were of short‐term nature. Nitrogen was most stable under arbuscular mycorrhizal species.
    Beschreibung: Deutsche Forschungsgemeinschaff (DFG)
    Schlagwort(e): ddc:551.9 ; ddc:631.41
    Sprache: Englisch
    Materialart: doc-type:article
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  • 8
    Publikationsdatum: 2022-09-30
    Beschreibung: In recent years, German cities were heavily impacted by pluvial flooding and related damage is projected to increase due to climate change and urbanisation. It is important to ask how to improve urban pluvial flood risk management. To understand the current state of property level adaptation, a survey was conducted in four municipalities that had recently been impacted by pluvial flooding. A hybrid framework based on the Protection Motivation Theory (PMT) and the Protection Action Decision Model (PADM) was used to investigate drivers of adaptive behaviour through both descriptive and regression analyses. Descriptive statistics revealed that participants tended to instal more low‐ and medium‐cost measures than high‐cost measures. Regression analyses showed that coping appraisal increased protection motivation, but that the adaptive behaviour also depends on framing factors, particularly homeownership. We further found that, while threat appraisal solely affects protection motivation and responsibility appraisal affects solely maladaptive thinking, coping appraisal affects both. Our results indicate that PMT is a solid starting point to study adaptive behaviours in the context of pluvial flooding, but we need to go beyond that by, for instance, considering factors of the PADM, such as responsibility, ownership, or respondent age, to fully understand this complex decision‐making process.
    Beschreibung: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347
    Schlagwort(e): ddc:551.489 ; ddc:363.34
    Sprache: Englisch
    Materialart: doc-type:article
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  • 9
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: The development of the Analytical Photogrammetry Compiler (APC) is traced and a detailed description is given of the component parts of the AP/C-4.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn retrace le developpement du restituteur analytique (APC) et on donne une description detaillée des composants du AP/C-4.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Skizzierung des Analytical Photogrammetry Compiler (APC) und detaillierte Beschreibung der Hauptbaugruppen der AP/C-4.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: The fifth biennial symposium of the Photogrammetric Society was held at the University of Birmingham on 6th to 8th April. It has been decided to perpetuate the memory of E. H. Thompson by giving his name to the series of symposia which originated at Birmingham in 1971 Eight papers were delivered to the 1979 symposium. They covered a wide variety of topics which included, in addition to a review of Thompson's own contribution to analytical photogrammetry, a modern approach to the handling of parallax measurements; aspects of digitising; low cost automatic contouring; high energy roentgen photogrammetry; applications in anatomy; the photogrammetric operator's point of view; and cadastral surveys. The majority of the papers are published in this issue of The Photogrammetric Record.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe cinquième symposium biennal de la Société de Photogrammétrie s'est dérouléà l'université de Birmingham du 6 au 8 Avril. On décida de perpétuer le souvenir de E. H. Thompson en donnant son nom à la série de symposiums inaugurée à Birmingham en 1971 Huit communications ont été présentées au symposium de 1979. Elles concernaient une grande diversité de sujets qui comprenaient, en plus d'une revue de la contribution de Thompson à la photogrammétrie analytique, une methode moderne de mesure de parallaxe; des aspects de la transformation digitale; une visée automatique à bas prix; la photogrammétrie Roentgen à grande energie; des applications en anatomie; le point de vue de l'opérateur en photogrammétrie; et des cadastres. La majorité des communications sont publicées dans ce numéro de The Photogrammetric Record.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Das 5. im Abstand von zwei Jahren von der Photogrammetric Society veranstaltete Symposium fand vom 6. bis 8. April an der Universität Birmingham statt. Es wurde beschlossen, in ehrendem Gedenken Prof. Thompsons seinen Namen dieser Serie von Symposien, die 1971 in Birmingham begonnen hat, zu geben.Auf dem Symposium 1979 wurden 8 Vorträge gehalten. Sie beinhalten ein breites Themenspektrum, darunter ergänzend zu einem äberblick über den Beitrag Thompsons zur analytischen Photogrammetrie, eine moderne Lösung zur Verarbeitung von Parallaxenmessungen, Aspekte der Digital-isierung, eine kostengünstige automatische Höhenlinienentwicklung, Röntgen-photogrammetrie, Anwendungen in der Anatomie, der Standpunkt des photogrammetrischen Auswerters und Katastermessungen. Die Mehrzahl der Beiträge wird in dieser Ausgabe des Photogrammetric Record veröffentlicht.
    Materialart: Digitale Medien
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  • 11
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: As part of his comprehensive analysis of cadastral surveys within the British Commonwealth (Dale, 1976), the author considered the contribution of aerial photography and photogrammetric surveys to this aspect of land administration. In this paper, he examines that contribution and underlines the limitations of photogrammetry as a cadastral survey method.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé L'auteur extrait de l'étude exhaustive qu'il a faite du levé cadastral dans le Commonwealth (Dale, 1976) tout ce qui a rapport à la photogrammétrie: contribution et limitations.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIn seiner umfassenden Analyse von Katastermessungen (Dale, 1976) betrachtete der Autor den Beitrag der Aerophotogrammetrie und photo-grammetrischer Messungen für die Landeinrichtung. In der vorliegenden Arbeit werden diese Ausführungen überpruft und in diesem Zusammenhang die Grenzen der Photogrammetrie herausgearbeitet.
    Materialart: Digitale Medien
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  • 12
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: A simple method is described for calibrating cameras at object distances of less than 0·5 m.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit une méthode simple pour calibrer les appareils de photographie pour des objets à des distances de moins de 0·5 m.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines einfachen Verfahrens zur Kammerkalibrierung für Aufnahmeentfernungen von weniger als 0·5 m.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 13
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: Book Reviewed in this article:CHARTERED LAND SURVEYOR/CHARTERED MINERALS SURVEYOR, Volume 1, Number 1, Spring 1979. Edited by M. Hanson.STUDENT MAP PACK. Dissected highland area: Maesteg, South Wales (Educational Map Series No. 10A). Industrial area: Washington New Town (Educational Map Series No. 11A).PHOTOGRAPHIC TECHNIQUES IN SCIENTIFIC RESEARCH, Volume 3. Edited by A. A. Newman.THE CAMERA AT WAR. By J. Lewinski.RECOGNITION OF TREE SPECIES ON AERIAL PHOTOGRAPHS. By L. Sayn-Wittgenstein.
    Materialart: Digitale Medien
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  • 14
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 15
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: Three investigations of the suitability of photogrammetry as a method of measurement are described, in the fields of marine, mechanical and structural engineering. Analytical solutions for a single model, a strip and a block of photographs are discussed.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit trois tentatives de recours à la photogrammétrie en métrologie industrielle, dans les industries de la marine, de la mécanique, et des structures métalliques. On discute l'intérêt des solutions analytiques pour le couple, la bande ou le bloc de photos.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung von drei Untersuchungen bezüglich Eignung der Photogrammetrie als Messverfahren im Schiffbau, im Maschinenbau und im Bauwesen. Diskussion analytischer Lösungen für das Einzelmodell, die Bildreihe und den Block.
    Materialart: Digitale Medien
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  • 16
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: The concept of optimum interpolation is briefly explained. The use of polynomial and non-polynomial stepwise regression for obtaining optimum or near optimum interpolation is illustrated. Least squares collocation is presented as an advanced method for optimising stepwise regression whenever the latter does not achieve desired optimum interpolation for given terrain. A Fortran IV program, written to illustrate an optimum interpolation algorithm using stepwise regression and collocation, is found to produce better results than existing interpolation methods. Other applications of such an algorithm are also discussed.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn expose brièvement le concept d'interpolation optimale, ainsi que les méthodes d'approximation polynomials ou autres qui permettent de la réaliser localement au mieux. On présente la collocation comme une méthode permettant de parachever l'interpolation; on a trouvé effectivement, avec un programme écrit en Fortran IV, que les résultats obtenus ainsi étaient meilleurs. On envisage aussi d'autre types d'applications de cet algorithme.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungKurze Erläuterung des Begriffs der optimalen Interpolation. Skizzierung der Anwendung von schrittweiser Regression mit Hilfe von Polynomen oder anderen Verfahren zur Ermittlung optimaler oder genähert optimaler Inter-polationen. Die Kollokation nach kleinsten Quadraten wird als verbesserte Methode zur Optimierung der schrittweisen Regression dargestellt, wenngleich letztere keine optimale Interpolation für ein gegebenes Gelände liefert. Ein Rechenprogramm in Fortran IV, das zur Veranschaulichung eines optimalen Interpolations-Algorithmus mit Hilfe der schrittweisen Regression und Kollokation geschrieben wurde, lieferte bessere Ergebnisse als vorhandene Interpolationsmethoden. Andere Anwendungen eines solchen Algorithmus werden ebenfalls erörtert.
    Materialart: Digitale Medien
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  • 17
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 18
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 19
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 20
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 21
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: An algorithm for the generation of digital ground models is described. The algorithm is based on an approximate solution and uses data obtained with simple measuring equipment. Processing of the observations is carried out by an on line desk top computer and the results of some tests are given.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit un algorithme pour la génération de modèles de terrain digitaux. L'algorithme est basé sur une solution approximative et utilise des résultats obtenus avec un appareil de mesure simple. Les observations sont etudiées par une ordinateur de bureau lié directement et on donne les resultats de certains travaux.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines Algorithmus zur Erzeugung digitaler Geländemodelle. Dieser basiert auf einer Näherungslösung und verwendet Daten, die mit einfachen Messgeräten gewonnen wurden. Die Datenverarbeitung wird mit Hilfe eines Tischrechners ausgeführt, und es werden einige Testergebnisse mitgeteilt.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 22
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: The author reviews procedures for obtaining stereomicrographs from binocular and monocular optical microscopes, from transmission and scanning electron microscopes and from an X-ray microscope. A description is given of the EMPD2 plotter for stereomicrographs and the advantages of various reconstruction techniques are considered, including a computer method used in the study of virus particles.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméL'auteur fait la revue des procédés qui permettent d'obtenir des stéréomicrographes à partir de microscopes optiques binoculaires et monoculaires, de microscopes electroniques transmetteurs et explorateurs et de microscopes radioscopiques. On donne une description de l'appareil de restituion EMPD2 pour les stéréomicrographes et on considère les avantages de diverses techniques de reconstruction, y compris d'une méthode avec ordinateur utilisée dans l'étude de particules de virus.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Autor gibt einen Überblick über Verfahren zur Aufnahme von Stereomikrofotos mit Hilfe binokularer und monokularer optischer Mikroskope, mit Hilfe von Durchstrahlungs- und Abtast-Elektronenmikroskopen sowie mit einem Röntgenmikroskop. Der EMPD 2 Plotter für Mikrostereofotos und die Vorteile verschiedener Rekonstruktionsmethoden, einschliesslich eines Rechnerverfahrens zur Untersuchung von Virus-Teilchen werden erörtert.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 23
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 24
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: Problems are sometimes encountered during the relative orientation of close range photography which has a limited usable format and a large Z range. Computer simulations and practical tests with both a comparator and a plotting instrument are used to investigate the problems and possible inaccuracies. Systematic errors in the photogrammetric model are revealed.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn rencontre souvent des difficultés lorsqu'on forme un modèle avec des clichés pris à courte distance, à format réduit et lorsque l'objet présente quelque profondeur. On a approfondi ces problèmes en utilisant conjointement simulations et essais pratiques; on a prouvé ainsi que les déformations du modèle étaient systématiques.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungMitunter ergeben sich bei der relativen Orientierung von Nahbereischsbildern Probleme, weil das nutzbare Bildformat klein und der z-Bereich gross sind. Mit Hilfe von Computer-Simulationen und praktischer Tests mit einem Komparator bzw. einem Auswertegerät wurden die Probleme und mögliche Ungenauigkeiten untersucht. Dabei wurden systematische Fehler in dem photogrammetrischen Modell aufgedeckt.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 26
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: Water currents in an hydraulic model have been determined by means of a photogrammetric method of detecting the movement of tethered buoys. Single vertical photographs, taken by a non-metric camera, have been analysed to produce the required differential measurements. The use of a non-metric camera is justified by an analysis of the errors involved and a consideration of the requisite type of measurements.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUne méthode photogrammétrique a été mise au point pour déterminer par mesures différentielles sur un modèle hydraulique les mouvements de bouées en vue d'étudier les courants; seules des photos verticales isolées sont prises, avec une camera non métrique, ici largement suffisante pour l'exactitude requise.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBestimmung der Wasserströmungen in einem hydraulischen Modell durch photogrammetrische Ermittlung der Bewegung von verankerten Bojen. Einzeine Steilbilder, die mit einer Amateurkamera aufgenommen wurden, dienten zur Ableitung der geforderten Differenzen-Messungen. Die Verwendung einer Amateurkamera wird durch eine Analyse der auftretenden Fehler und eine Betrachtung der geforderten Messungswerte gerechtfertigt.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 27
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 28
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 29
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: Book Reviewed in this article:THE GEOGRAPHER AS A MAP-MAKER. By A. Hodgkiss.ARCHITECTURAL PHOTOGRAMMETRY. By R. W. A. Dallas.BIBLIOGRAPHIA CARTOGRAPHICA Volume 4 (1977). Edited by L. Zögner.PRINCIPLES OF SURVEYING. By J. G. Olliver and J. Clendinning.THE ELEMENTS OF ASTRONOMY FOR SURVEYORS. By J. B. Mackie.JOURNËE D'ËTUDE SUR LA STËRËO-ORTHOPHOTOGRAPHIE.THE NAZI CONNECTION. By F. W. Winterbotham.AERIAL ARCHAEOLOGY. Edited by D. A. EDWARDS and C. R. Partridge.PHOTOGRAPHY BY INFRARED. ITS PRINCIPLES AND APPLICATIONS. By H. Lou Gibson.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 30
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: This article provides a brief description of the functions and capabilities of an image generating system developed by Linotype-Paul Limited for the Royal Aircraft Establishment, Farnborough.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Cet article donne une courte description des fonctions et des possibilités d'un système generateur d'images developpé par Linotype-Paul Limited pour Royal Aircraft Establishment, Farnborough.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Kurze Beschreibung der Funktionen und Fähigkeiten eines bilderzeugenden Systems, das bei der Linotype-Paul Limited für das Royal Aircraft Establishment in Farnborough entwickelt wurde.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 31
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 9 (1979), S. 0 
    ISSN: 1477-9730
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Architektur, Bauingenieurwesen, Vermessung
    Notizen: This paper describes the production of stereopairs of shadow photographs to simulate X-ray pictures and demonstrates the possibility of determining analytically the precise position in the object space of foreign bodies using a digitiser as a monocomparator and projective transformation theory to dispense with the necessity of undertaking normal inner and relative orientation analytical procedures.A model is constructed and comparison accuracy tests are made using shadow and X-ray picture pairs. The paper also suggests that the use of projective transformation theory is more appropriate in short range photogrammetry than traditional topographic stereophotogrammetric theory.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméCette communication décrit la production de couples stéréoscopiques de photographies d'ombre pour simuler des radiogrammes et démontre la possibilité de determiner analytiquement la position exacte dans l'espace de l'objet de corps étrangers en utilisant un transformateur digital comme mono comparateur et une théorie de transformation projective pour dispenser de la nécessité d'entreprendre les procédés normaux d'orientation analytique interieurs et relatifs.On construit un modèle et on fait des testes précis de comparaison en utilisant des couples de photographies d'ombre et de radiogrammes. La communication suggère aussi que l'utilisation de la théorie de transformation projective est plus appropriée pour la photogrammétrie à champs court que la théorie traditionnelle de stéréophotogrammétrie topographique.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird die Herstellung von Stereobildpaaren von Schatten-Fotos beschrieben, womit Röntgenbilder simuliert und die Möglichkeit der analytischen Bestimmung der präzisen Lage von Fremdkörpern im Objektraum gezeigt werden sollten. Dazu wurde ein Monokomparator als Digitalisiervorrichtung und die Theorie der projektiven Transformation angewendet, urn auf die sonst übliche analytische Bestimmung der inneren und relativen Orientierung verzichten zu können.Es wurden ein Modell konstruiert und vergleichende Genauigkeitstests für aus Schatten-Fotos bzw. Röntgenbildern bestehende Bildpaare durchgeführt. Im Beitrag wird die Meinung vertreten, dass die Theorie der projektiven Transformation bei der Nahphotogrammetrie günstiger ist, als die traditionelle Theorie der topographischen Stereophotogrammetrie.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 32
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 33
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Examination of stained specimens (protargol and nigrosinbutanol) of hypotrich ciliates during division allows understanding of morphogenesis of buccal structures and cirri. Midventral, frontal, and transverse cirri in both proter and opisthe of Urostyla marina differentiate from a longitudinal series of numerous oblique ciliary streaks in a manner similar to that of Bakuella, Holosticha, Keronopsii. Pseudourostyla, and Uroleptus. This pattern differs markedly from that in Amphisiella, Kahliella, Paraholosticha, and Paraurostyla, in which the fronto-ventral and transverse cirri arise from a series of fewer (2–5) ciliary streaks in a longitudinal or fan-like array. Rows of marginal cirri in U. marina arise independently, as in Urostyla grandis. On the basis of comparisons of both structural and morphogenetic features of this and other hypotrichs, the family Urostylidae is redefined to contain Urostyla (type), Bakuella, Holosticha, Keronopsis, Pseudourostyla, and Uroleptus. Other genera formerly contained in the families Holostichidae and Urostylidae are placed in synonymy, assigned to other families, or held in uncertain familial relationship pending their rediscovery and further investigation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 34
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSISUltrastructure of the plasmodium wall and of sporogenesis were studied in Myxosoma funduli Kudo infecting the gills of Fundulus kansae (Garman). Plasmodia were located within the lamellar tissues adjacent to sinuses and capillaries. The plasmodium wall consisted of a single unit membrane which was continuous with numerous pinocytic canals extending into the parasite ectoplasm. The plasmodium membrane was covered by a surface coat of almost uniform thickness which prevented direct parasite-host cell contact. Numerous generative cells and cell aggregates, representing early stages of spore development, were seen in immature plasmodia. Later stages of spore development, including mature spores, were observed in older plasmodia. Sporogenesis was initiated by envelopment of one generative cell, the sporont, by a 2nd, nondividing cell, the envelope cell. The sporont and its progeny proceeded through a series of divisions until there were 10 cells, all compartmentalized within the envelope cell. Subsequently, the 10 cells became structurally differentiated and arranged into two 5-celled spore-producing units, each consisting of 1 binucleate sporoplasm and 2 capsulogenic cells, all surrounded by 2 valvogenic cells. Observations of later developmental stages revealed the major events of capsulogenesis, valvogenesis, and sporoplasm maturation, which occurred concomitantly during spore construction.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 35
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Richmond, M. H. & Smith, D. C., eds. 1979. The Cell as a Habitat.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 36
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Exoerythrocytic merozoites of Plasmodium lophurae grown in embryonic turkey brain cells were successfully separated from host cell material by elution from a DEAE-cellulose column at ionic strength 0.22. Purity of parasite samples was assessed by sodium dodecyl sulphate acrylamide gel electrophoresis and electron microscopy. Increasing the ionic strength gave greater recoveries of merozoites, but host cell contamination increased.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 37
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Blastocrithidia culicis, Crithidia deanei, Crithidia fasciculata, Herpetomonas samuelpessoai, Leptomonas seymouri and Leishmania tarentolae grown in cultures were compared by electrophoretic mobility for isoenzymes in 6 enzymes. All species were found distinct in these characteristics. Endosymbiotic C. deanei, which was identical to the aposymbiotic C. deanei in 5 enzymes, had an extra band in aspartate aminotransferase. No differences in isoenzymes were found between members of one species maintained in 2 different culture media.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 38
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: RESUME.Des divisions synchrones chez Euglena gracilis Z peuvent ětre obtenues par différentes méthodes. Lorsque les cellules sont cultivées sur milieu contenant du lactate comme seule source de carbone, des divisions synchrones sont observables, indépen-damment des conditions d'éclairement. Toutefois, il existe une relation entre la phase des divisions cellulaires et les périodes lumière-obscurité appliquée à la culture.Pendant le cycle cellulaire, nous montrons que les synthèses des macromolécules sont discontinues: c'est le cas pour les ADN nucléaire et mitochondrial, les ARN ribosomaux et non-ribosomaux, ainsi que pour certaines protéines (cytochrome c 558). Des variations cycliques touchant la morphologie des mitochondries et des chloroplastes sont observées. Au cours du cycle cellulaire, les processus métaboliques séquentiels accompagnent les modifications de structure des organites. C'est ainsi qu'en début du cycle, au commencement de la phase G1, sont synthétisés les ribosomes cytoplasmiques et qu'ensuite, chez les euglènes vertes, les ARN non-ribosomaux sont formés.Ces synthèses d'ARN précèdent l'accroissement du chondriome et du plastidome dans la cellule. En milieu de phase G1, une nouvelle synthèse d'ARN non-ribosomal commence et est observée avant la synthèse des ADN nucléaire et mitochondrial. En fin de phase G1, démarre la division des organites à partir du chondriome et du plastidome en réseau.SYNOPSIS.Synchronous divisions of Euglena gracilis strain Z can be obtained by various methods. When the cells are cultivated in a medium containing lactate as the sole carbon source, synchronous divisions are observed, independent of the conditions of illumination. Nevertheless, there exists a relationship between the phase of cell division and the periods of light and darkness applied to the culture.During the cell cycle, the synthesis of macromolecules is discontinuous—this is true of nuclear and mitochondrial DNA, ribosomal and nonribosomal RNA, and certain proteins (cytochrome c 558). Cyclic variations in the structure of mitochondria and chloroplasts are also observed. In the course of the cell cycle, sequential metabolic processes accompany structural modifications of the organelles. Also, at the beginning of the cycle, at the start of phase G1, the cytoplasmic ribosomes are synthesized, and then, in green euglenids, nonribosomal RNAs are formed. These syntheses of RNA precede enlargement of the chondriome and plastids. In mid-G1 phase, a new synthesis of RNA begins, which precedes synthesis of nuclear and mitochondrial DNA. At the end of G1 phase, division of organelles starts, beginning with the chondriome and plastids, arranged in a network.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 39
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Cell-free synthesis of high molecular weight polypeptides, programmed by RNA from Tetrahymena pyriformis strain W is reported, and methods for preparation of the RNA are described. The RNA was extracted by the SDS-phenol-chloroform-isoamyl alcohol technic. The bulk of extracted RNA was ribosomal and on sucrose gradients peaked at -17S and 25S. After heat denaturation all the 25S RNA was converted to 17S. indicating the presence of hidden breaks, possibly the result of nuclease activity during extraction. Nevertheless, when poly(A)–RNA was collected using oligo-(dT)-cellulose column chromatography, it promoted a 15–fold increase in incorporation of [35S] methionine into TCA-precipitable material. Slab-gel electrophoresis and autoradiography of the product revealed 12 different major polypeptides, varying in weight from 28.000 to 65,000 Daltons. A method for preparation of translatable RNA from Tetrahymena will make possible the comparison of messenger RNAs associated with specific cell structures and with different developmental events.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 40
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Lorica building was studied experimentally for Tintinnopsis parva Merkle, an agglutinated tintinnid. This species incorporated either siliceous or Ca-rich particles. Evidence of agglutination was seen within 30 min after the addition of particles to cultures of the protozoa. Fully agglutinated loricae were produced by the proter; partially incrusted loricae attributed to an opisthe were also recovered. The cytoplasmic evaginations of unknown function called striae were seen in the scanning electron microscope in better relief than ever before. They may provide the mechanism whereby the enclosed capsules are brought into contact with prey organisms.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 41
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Culture procyclic forms of Trypanosoma brucei rhodesiense and Trypanosoma congolense were fed to Glossina morsitans morsitans through artificial membranes. A very high percentage of the flies so fed produced established midgut infections, a proportion of which went on to develop into mature metacyclic trypanosomes capable of infecting mammalian hosts. The method offers a safe, clean way of infecting tsetse flies with African trypanosomes which reduces the need for trypanosome-infected animals in the laboratory.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 42
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. The helical coiling state of a glycerinated stalk in the family Vorticellidae had been regarded, without any evidence, as a reversible and completely equilibrated mechano-chemical system regulated by the external free Ca2+ concentration. Our present detailed observations of many individual stalks of glycerinated Vorticella convallaria revealed that the contraction-extension cycle of the helical stalks caused by increasing and decreasing free Ca2+ concentrations in the medium represents a kind of hysteresis. This phenomenon was observed in extensively glycerinated Vorticella in a medium of very low or physiological ionic strength, as well as in briefly glycerinated ciliates. With regard to the configurational change in various parts of a glycerinated stalk during the contraction-extension cycle, it was found that the initial bending of the stalk caused by increasing free Ca2+ concentration begins to take place near the zooid (head) while the initial reextension of the stalk with decreasing free Ca2+ concentration begins to take place near the zooid (head) while the initial reextension of the stalk with decreasing free Ca2+ concentration takes place simultaneously throughout the entire stalk. The Ca2+ threshold for complete reextension of the part of the stalk near the rootlet was found to be much higher than that near the zooid.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 43
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Amblyospora sp. in Culex salinarius (Coquillett) is transovarially transmitted and has 2 developmental sequences, one in each host sex. In females, the entire life cycle is restricted to oenocytes which become greatly hypertrophied due to the multiplication of diplokaryotic cells during merogony and come to lie next to ovaries. Sporulation occurs only after a blood meal is taken and is shortly followed by infection of the oocytes and subsequent transmission to the next host generation. In the male host, infections spread from oenocytes to adipose tissue where diplokaryotic cells undergo a 2nd merogony. During this merognic cylce, the number of diplokaryotic cells greatly increases and the infection is spread throughout the body of the larval host. Sporulation is initiated with the physical separation of the 2 members of the diplokaryon and the simulatneous secretion of a pansporoblastic membrane. Subsequent meiotic division and morphogenesis result in the formation of 8 haploid spores enclosed with a pansporoblastic membrane. Buildup of spores and subsequent destruction of host adipose tissue prove fatal to the male host during the 4th larval stage.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 44
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Glutamate decarboxylase, γ-aminobutyrate-α-ketoglutarate aminotransferase and NAD-linked and NADP-linked succinic semialdehyde dehydrogenase, all constituting the GABA (γ-aminobutyrate)-shunt pathway of glutamate metabolism are localized in the mitochondrial matrix in a streptomycin-bleached mutant of Euglena gracilis strain Z. Glutamate dehydrogenase, requiring NADP as the cofactor, was distributed in the cytoplasm. An improved version of the controlled digestion method for preparing Euglena mitochondria, which involves use of trypsin and a trypsin inhibitor and removal of broken cells before mechanical disruption of cells, is also described.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 45
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. By phenol extraction and DEAE cellulose column chromatography, tRNA was isolated from Tetrahymena pyriformis strain GL. Following acid hydrolysis of the tRNA, the methylated purine content was determined by Dowex 50 column chromatography and paper chromatography.The most abundant methylated guanine derivative was found to be N2-DMG. Also present were 1-MG, N2-MG, and 7-MG. The most abundant methylated adenine was found to be 1-MA; no 2-MA was detected. Small amounts of the N6-methyladenines were detected.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 46
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Corliss, John O. 1979. The Ciliated Protozoa. Characterization, Classification and Guide to the Literature.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 47
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: New fish species and geographic records for Rhabdospora thelohani Laguessé, 1895 (rodlet cells) are presented. Additionally, the ultrastructure of R. thelohani in Alburnoides bipunctatus ohridanus Karaman, Borostomias antarcticus (Louml;nnberg), Leuciscus cephalus albus Bonaparte and Rutilus rubilio (Bonaparte) is compared with that reported by other authors and with members of Subphylum Apicomplexa. The ultrastructure of R. thelohani was similar in all the fish species examined: however, the organism was not present in all members of any single species and had intertissue density variations. Rhabdospora thelohani is pyriform. averaging in size 7 × 12 m̈, with a basal nucleus. The surface complex is composed of a layer (0.5 m̈m diameter) formed by microfilaments (9.3 nm) and an outer trilaminar membrane (9.3 nm). The cytoplasm contains structures identical to rhoptries, micronemes and subpellicular microtubules. Mitochondria. Golgi apparatus, and rough endoplasmic reticulum were not observed, although free ribosomes were present and arranged in a vesicular pattern. The observations suggest that the organism moves between cells of epithelial layers and is either released into a lumen intact or passively or actively discharges its contents into a lumen. Results from this study indicate that R. thelohani should be considered a member of Apicomplexa unless definitive evidence is presented to the contrary.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 48
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Kallinikova, V. D. 1977. Kletochnaya Organella Kinetoplast. [The Kinetoplast, a Cell Organelle (in Russian).]
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 49
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: McClure, H. E., Poonswad, P., Greiner, E. G. Laird, M. 1978. Haematozoa in the Birds of Eastern and Southern Asia.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 50
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Long, P. L., Boorman, K. N. Freeman, B. M. 1978. Avian Coccidiosis. Poultry Science Symposium #13.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 51
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: The effect of exposure period and concentration of algae on the frequency of infection of aposymbiotic ciliates by algae obtained from the same clone of Paramecium bursaria syngen 2, was studied. The frequency of infection was roughly proportional to the algal concentration and to the exposure time of ciliates to algae. The relationship of algal concentration to infection frequency closely fitted the Poisson distribution curve for N = 1, suggesting that the minimum number of algae required to infect a single ciliate is 1. However, the data also strongly suggested that the average number of algae required to initiate infection of an average ciliate was ˜ 1,000. Three possible resolutions of this situation are: (a) the selection by the ciliate of a rare infective variant from a heterogeneous population: (b) the rare escape of an alga from digestion by the ciliate; and (c) the requirement for a large number of algae-ciliate contacts to induce susceptibility in the ciliate. Splitting the exposure of ciliates to algae into 2 periods of 0.5 h, separated by 5 h in the absence of algae, produced a much higher frequency of infection than a single l-h exposure, supporting the suggestion that the large number of algae is required to induce susceptibility in the ciliate which can then be infected by as few as a single algal cell.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 52
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: A plaque technic was evaluated and used for the isolation and enumeration of small, free-living amebae in lake-bottom samples which were collected each month for one year from a Nebraska lake. Several culture media were evaluated, and a simple glucose-salts medium was chosen. The most frequent ameba in the lake-bottom samples was Acanthamoeba polyhaga which underwent marked increases and decreases in population densities during the collection period. This pattern was not correlated with water temperature, bacterial counts, and nitrate or phosphate levels. Other species of amebae of the genera Hartmannella, Vahlkampfia, Naegleria, Paratetramitus and Echinamoeba were isolated. Most of these were either found infrequently or remained at relatively low, constant densities throughout the year. In addition, 4 species of Acrasieae of the genera Dictyostelium and Polysphondylium were isolated from the lake-bottom samples.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 53
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Hydroxyurea (HU) inhibits increase in cell number in cultures of Crithidia fasciculata. Complete inhibition is produced by 8 mM and higher concentrations. If HU is not removed, population growth resumes in 45–50 h: if HU is removed, partially synchronous growth occurs through 2 cycles. During HU inhibition, the rate of DNA synthesis is reduced to 1% of that in exponentially growing cultures; protein and RNA syntheses continue at slightly reduced rates. Mean cell size and protein and RNA contents per cell increase; rate of oxygen consumption per mg cell protein remains constant. The behavior of a culture upon addition of HU and upon its removal agrees with predictions based on the hypothesis that the only direct effect of HU is to block DNA synthesis. The synchrony produced by HU is judged satisfactory for investigations of kinetoplast and nuclear replication but not for biochemical characterization of other aspects of the cell cycle.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 54
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Dihydrofolate reductase (E.C. 1.5.1.3) from Plasmodium falciparum and from its host, the owl monkey (Aotus trivirgatus). were partially purified and characterized. The molecular weight of the parasite enzyme was estimated to be over 10 times as high as that of the host enzyme. The host enzyme had 2 pH optima whereas the parasite enzyme only one. The activity of the host enzyme was greatly stimulated by KCI and urea, while that of the parasite enzyme was inhibited at high concentrations of such chaotropic agents. Km of the parasite enzyme was significantly higher than that of the host enzyme. The parasite enzyme had much lower Ki for pyrimethamine than the host enzyme. Dihydrofolate reductases isolated from pyrimethamine-resistant and pyrimethaminesensitive strains of P. falciparum were found to be similar.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 55
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: The chelator GEDTA was used to show that Ca2+ is required for the growth of Tetrahymena pyriformis strain W and for normal galvanotactic responses and swimming.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 56
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Entamoeba histolytica required CO2 for growth in axenic culture while growth was inhibited by H2. The organism was tolerant to 5% O2 in the gas phase and it was able to detoxify products of O2 reduction in the medium. The ameba did not require a negative oxidation-reduction potential for axenic growth. However, little or no free O2 was present in media exposed to 5% O2 in the gas phase. Growth was improved by adding yeast extract to the medium.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 57
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Twelve acid hydrolases, 4 near-neutral hydrolases and alkaline phosphatase were demonstrated in 0.34 M sucrose homogenates of Trypanosoma cruzi strain Y: p-nitrophenylphosphatase and α-naphthylphosphatase, with optimum pH at ˜ 6.0; α-galactosidase, β-galactosidase, β-glucosidase, N-acetyl-β-glucosaminidase, cathepsin A and peptidase I and III, with optimum pH between 5.0 and 6.0: and arylsulfatase cathepsin D, α-arabinase and α-mannosidase with optimum pH at ˜ 4.0 α-Glucosidase, gluccse-6-phosphatase and peptidase II had optimum pH at ˜ 7.0. β-Glycerophcsphatase had a broad pH-activity curve from 4.0 to 7.4, with maximum activity at pH 7.0. The main kinetic characteristics of these enzymes and their quantitative assay methods were studied.No activity was detected for α-fucosidase, β-xylosidase, β-glucuronidase, elaidate esterase. acid lipase, and alkaline phospho-diesterase.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 58
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 59
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Vitamin B12 deficiency arrests cell division in Euglena gracilis. B12 starvation for short periods made it possible to induce synchronous growth by addition of the vitamin. Culture conditions were established to optimize replenishment synchrony. The DNA content of E. gracilis in steady state culture and vitamin B12 deficiency culture was measured by flow cytofluorometry and was consistent with colorimetric determinations. The cell volume and DNA distributions of E. gracilis in synchronous culture were analyzed and the sequential changes during the division cycle were computed. Synchronous culture permits more definitive studies of shifts in cell volume and DNA distributions, in which the biochemical events required for cell division are presumably synchronized.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 60
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Atypical eukaryotic RNA polymerase activity was demonstrated in nuclei of Crypthecodinium cohnii, a eukaryote devoid of histones. Nuclei were isolated from growing cultures of this dinoflagellate and assayed for endogenous RNA polymerase (EC 2.7.7.6) activity. There was a biphasic response to Mg2+ with optima at ˜ 0.01 and 0.02 M MgCl2, but in contrast to other eukaryotic RNA polymerases, this enzyme activity was inhibited by low MnCl2 concentrations. In the presence of 0.01 M MgCl2 the optimum (NH4)2SO4 concentration was 0.025 M, a concentration at which the nuclei were lysed. Incorporation of [3H]UMP into RNA was inhibited by actinomycin D and dependent on the presence of undegraded DNA, and the reaction product was sensitive to ribonuclease and KOH digestion. Omission of one or more ribonucleoside triphosphates greatly reduced the incorporation. Only a slight enhancement of RNA polymerase activity resulted from the addition of various amounts of native and denatured calf thymus DNA. Spermine caused a marked inhibition while spermidine had little effect on RNA synthesis in the nuclei. Under the optimum conditions described in the present paper the nuclei incorporated ˜ 3 pmoles of [3H]UMP/muml; DNA at 25 C for 15 min, and ˜ 80% of this activity was inhibited by the eukaryotic RNA polymerase II inhibitor, α-amanitin (20 m̈/ml). A unique situation therefore exists in C. cohnii nuclei, in which absence of histones (a prokaryotic trait) is combined with α-amanitin-sensitive RNA polymerase activity (a eukaryotic trait).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 61
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: After demonstration that emetine is amebicidal by inhibiting protein synthesis, the question arose whether active protein synthesis is required for emetine's amebicidal effect. The answer appears to be “no,” as derived from experiments on intact amebae. Responses were compared for log- and stationary-growth phase amebae. In the latter, protein synthesis is significantly slower, and sensitivity to emetine, i.e. degree of inhibition of protein synthesis, was maintained independently of rate of protein synthesis. Both stages equally bound tritiated emetine to their ribcsomes. Binding of [3H]emetine was not affected by certain drugs that interfere with energy metabolism, protein synthesis, and/or ribosomal function, e.g. dinitrophenol, puromycin, chloroquine, and acriflavin. High concentrations of EDTA combined with puromycin (which disaggregates ribosomes into their subunits) lowered binding by 50%.In chase experiments the ribosomes of intact amebae were prelabeled with [3H]emetine or [3H]isoemetine, then exposed to relatively high concentrations of unlabeled emetine. Labeled isoemetine was displaced almost completely, whereas no displacement of [3H]emetine occurred; evidently, the high stability of the emetine-ribosome binding is due in part to a hydrogen-bonding reaction of the C-1' atom of the emetine molecule with the chain-elongation site. Finally, evidence was obtained that capacity to bind emetine is an index of drug resistance.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 62
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Four new eimerian species are described from red-backed voles. Clethrionomys gapperi in Pennsylvania. Sporulated oocysts of Eimeria clethrionomyis sp. n. are ellipsoidal, 18.8 (16.5–21.5) × 14.9 (14.0–16.5) with elongate, ovoid sporocysts, 10.6 (9.5–12.0) × 6.1 (5.5–7.0). The oocyst wall is smooth, with 2 layers, and thins, with terminal cap at one or both ends. Polar granules, dark Stieda body and sporocyst residuum are present. The occyst residuum is absent. Sporulated oocysts of Eimeria gallatii sp. n. are ellipsoidal, 27.7 (21–32) × 19.3 (17–24) with ovoid sporocysts, 13.5 (12–15) × 8.8 (8–10). The oocyst wall is smooth, 2-layered, with a micropyle and thin wall at the end opposite the micropyle. Polar granules. Stieda body and sporocyst residuum are present. The oocyst residuum is atypical, of cobwebby material. Sporulated oocysts of Eimeria pileata sp. n. are subspherical to spherical, 25.2 (20.5–29.5) × 22.5(19.5–25.5) with ellipsoidal sporocysts, 13.4(10.5–15.0) × 8.4 (7.5–9.5). The oocyst wall is rough, pitted, striated, 2-layered, with no micropyle. Polar granules, oocyst and sporocyst residuum. Stieda body and stiedal cap are present. Sporulated oocysts of Eimeria marconii sp. n. are ellipsoidal, 13.0 (10.5–15.0) × 10.6 (9.5–12.0) with elongate, ovoid sporocysts, 7.7 (7.0–8.5) × 4.2 (3.0–4.5). The oocyst wall is smooth, single-layered, with no micropyle. Polar granules, dark Stieda body and sporocyst residuum are present. There is no oocyst residuum.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 63
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS The ethanolic phosphotungstic acid (PTA) technic was used to detect, at the fine-structural level, basic proteins in various developmental stages of pathogenic Trypanosoma cruzi, and nonpathogenic Herpetomonas samuelpessoai, Leptomonas samueli, and Crithidia deanei, trypanosomatids. Reactions were observed in the nucleus of all stages. In the kinetoplast of epimastigote and promastigote forms reactions were noted mainly at the periphery. In trypomastigotes and choanomastigotes forms, however, an intense reaction was observed throughout the kinetoplast. Reactions were present in cytoplasmic vesicles related to protein storage in T. cruzi and in membrane-bounded peroxisome-like organelles of H. samuelpessoai, L. samueli and C. deanei. The network of filaments which forms the paraxial rod did not react. In the flagellum, reaction was noted only at the peripheral doublet microtubules. PTA reacts also with structures related to the junction between the flagellar and cell body membranes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 64
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Administration of the thymidine analog 5-bromodeoxyuridine to exponentially growing cultures of Tetrahymena pyriformis GL in chemically defined medium results in inhibition of cell multiplication by at least one generation before DNA synthesis stops. Cell multiplication can be restored in these cultures, if they are transferred to fresh growth medium, but although most of the cells in the culture contain close to a G2-amount of DNA, a full DNA replication round is a prerequisite for renewed cell multiplication. Large extrusion bodies are found at the first division after transfer to fresh growth medium. Autoradiographic analysis has revealed that the DNA in the extrusion body is a representative of the DNA in the macronucleus indicating a random distribution of DNA between daughter nuclei and extrusion body.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 65
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Bold, H. C. & Wynne, M. J. 1978. Introdirction to the Algae. Structure and Reproduction.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 66
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Oocysts of Eimeria filamentifera sp. n. were isolated from 2 of 2 snapping turtles, Chelydra serpentina (Linné), in Iowa. The ovoid to ellipsoid oocysts of this species averaged 23.2 × 18.6 μm and had a length/width ratio ranging from 1.1 to 1.6. The ellipsoid sporocysts averaged 14.0 × 7.7 μm and had papillose, filament-bearing Stieda bodies. Oocyst and sporocyst residua were present, but micropyle and polar granule were not. This appears to be the 2nd species of Eimeria reported from snapping turtles, with E. chelydrae being the first.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 67
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. First-generation schizogony of Eimeria bovis in bovine cell culture was studied by electron microscopy. The intracellular sporozoite retained its structure for at least 6 days at which time it rounded up and lost its apical complex. Although the refractile body underwent certain morphologic changes, it was retained throughout the parasite's growth. The beginning of mitosis was marked by the formation of a cytoplasmic funnel which traversed the nucleus opening on each side toward a pair of centrioles. Subsequently, there developed an intranuclear spindle. Separation of the daughter nuclei was preceded by the formation of typical centrocones. Differentiation of merozoites was accomplished by exogenesis during the last mitotic division. A dense fiber, interpreted as a link connecting the merozoite anlage with its nucleus, extended from the developing apical complex to the nearest division pole. In the anlage, the inner membrane complex was at first composed of patches associated with pairs of subpellicular microtubules. Rhoptries appeared early in merogenesis, whereas micronemes formed at the time the merozoites detached from the residuum. The level of amylopectin, low in schizonts, rose at the beginning of merozoite formation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 68
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Structure of Trypanoplasma beckeri sp. n. from the cabezon, Scorpaenichthys marmoratus (Ayres), is described from living specimens and from both Giemsa-, and protargol-stained smears. Flagellates from fish blood were usually long and slender, averaging 109.0 × 6.5 fan. The anterior flagellum averaged 8.5 μm; the recurrent flagellum bordered the body and terminated as a very short free flagellum, 2.5 μm long on the average. No true undulating membrane was observed, but in living individuals the recurrent flagellum undulated rapidly near its point of origin. The oval nucleus, averaging 8.5 × 4.0 μm, was located near the anterior cad of the body. An argentophilic, aciculum-like structure appeared to connect the nucleus to the area at the base of the flagella. The kinetoplast was not observed in fish blood forms. On the basis of laboratory experiments, the leech, Malmiana diminuta Burreson, was ascertained to be the vector for T. beckeri. Upon entry into the leech, flagellates became rounded, and division commenced within a few hours. Division continued for ˜48 h and the flagellates became progressively smaller until reaching a length of ˜10.0 μm. After 72 h they were found in high numbers in the proboscis sheath and also in the anterior crop of the leech. When infected leeches fed on an uninfected fish, flagellates were first observed in the fishes’ peripheral circulation 8 days later.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 69
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. It is evident from a survey of the Russian literature that many species of avian haematozoa recorded do not meet the basic criteria required by the International Code of Zoological Nomenclature. Thus 28 species of Haemoproteus and 4 species of Leucocytozoon are considered to be nomina nuda, while 1 species, Leucocytozoon turtur orientalis is a synonym of L. marchouxi.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 70
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Gamogony of Theileria ovis Rodhain occurs within the gut of nymphs of the tick Rhipicephalus evertsi evertsi Neumann. After molting, spherical and ovoid parasites are found within the intestinal cells of the ticks. These stages are thought to be zygotes, because they undergo a transformation process leading ultimately (in 3 days) to the formation of a motile stage, the kinete, the fine structure of which is very similar to that of the ookinetes of the hemosporidia. The kinete leaves the gut cells of the tick and penetrates the salivary gland cells where it produces infective stages (the sporozoites). These stages may be transmitted to sheep during the next blood meal of the tick. The developmental processes of T. ovis are compared to those of Hemosporina.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 71
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Kreier, J. P., ed. 1978. Parasitic Protozoa, Volume II, Intestinal Flagellates, Histomonads, Trichomonads, Amoeba, Opalinids, and Ciliates.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 72
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. The endogenous development of Isospora rivolta (Grassi) was studied in cats fed oocysts, and was compared with the endogenous cycle after feeding them mice infected with I. rivolta. For the mouse-induced cycle, 14 newborn cats were killed 12 to 240 h after having been fed mesenteric lymph nodes and spleens of mice. Asexual and sexual development occurred throughout the small intestine, in epithelial cells of the villi and glands of Lieberkuhn. The number of asexual generations was not determined with certainty, but there were at least 3 structurally different meronts. Type I meronts appeared at 12–48 h postinoculation (HPI). They were 8.5(6–13) × 5.1(3–6) μm, contained 2–8 merozoites, and divide by binary division or endodyogeny. Type II meronts were multinucleate merozoite-shaped meronts within a single parasitophorous vacuole. They were found at 48–172 HPI and measured 12.6(9–18) × 9.8(9–13) μm. Individual multinucleate merozoite-shaped meronts were 7–13 × 3–5 μm in sections and contained 2–30 slender (5.5 × 1.0 μm) merozoites. Type III meronts occurred at 72–192 HPI and gamonts at 72–96 HPI. Mature microgamonts measured 11.3(9–15) × 8.0(6–9) μm in sections and up to 21.5 × 14 μm in smears, and contained up to 70 microgametes. Macrogamonts measured 13.3(11–18) × 9.0(5–13) μm in sections and 18 × 16 μm in smears. Oocysts were 10–15 × 9–15 μm in sections and 19.8(17–24) × 18.0(17–23) μm in fixed and stained smears. Unsporulated oocysts in feces were 22.3(18–25) × 19.7(16–23) μm and spomlated oocysts 25.4(23–29) × 23.4(20–26) μm. Sporulation was completed within 24 h at 22–26 C. For the study of the oocyst-induced cycle in cats, 18 newborn cats were killed between 6 and 192 HPI. The endogenous development was essentially similar to the mouse-induced cycle, but merogony and gametogony occurred 12–48 h later than in the latter cycle. Isospora rivolta was pathogenic for newborn but not for weaned cats. Newborn cats fed 105 sporocysts or infected mice usually developed diarrhea 3–4 days after inoculation. Microscopically, desquamation of the tips of the villi and cryptitis were seen in the ilium and cecum in association with meronts and gamonts.For the study of the development of I. rivolta in mice, mice were killed from day 1 to 23 months after having been fed 105–105 sporocysts, and their tissues were examined for the parasites microscopically, and by feeding to cats. The following conclusions were drawn. (A) Isospora rivolta most frequently invaded the mesenteric lymph nodes of mice and remained there for 23 months at least. It also invaded the spleen, liver, and skeletal muscles of mice. This species could not be passed from mouse to mouse. Sporozoites increased in size from ˜6.8 × 4.9 μm on day 1 to ˜13.4 × 6.9 μm on day 31 postinoculation. Division was not seen.Prepatent period was 4–7 days and patent periods ranged from 2 to several weeks.
    Materialart: Digitale Medien
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  • 73
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Cells of the insect flagellate Crithidia fasciculata contained mannan and arabinogalactan components, whose porportion varied with culture age, the former predominating during early stages, and the latter during the later stages of exponential growth and the deceleration phase. The mannan was a β-D-(1→2)-linked D-mannopyranan. The arabinogalactan had a complex structure containing, in part, a β-D-(1→-3)-linked galactopyranose main-chain substituted in the 2 positions by single-unit D-arabinopyranose side-chains and with some unsubstituted units.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 74
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: McClure, H. E., Poonswad, P., Greiner, E. C. & Laird, M. 1978. Haematozoa in the Birds of Eastern and Southern Asia.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 75
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Scholtyseck, E. Fine Strirctirre of Parasitic Protoxm. An Atlas of Microgruphs, Druwings und Diagrams.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 76
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Agamococcidiorida ord. n. and Rhytidocystidae fam. n. are established in the apicomplexan subclass Coccidiasina for the genus Rhytidocystis Henneguy, 1907. Dehornia Porchet-Henneré, 1972 is synonymized with Rhytidocystis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 77
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: The process by which malaria parasites are killed in sickled erythrocytes was studied by electron microscopy. In vitro cultures of Plasmodium falciparum in sickle cell hemoglobin (HbS) homozygous (SS) and heterozygous (SA) red cells were deoxygenated for up to 6 h and fixed under anaerobic conditions. Parasites in SS cells appeared to be disrupted by intrusions of needle-like deoxyHbS aggregates; disintegration of cytoplasm and membranes followed. In SA red cells, the parasites were generally not disrupted. Instead, extensive vacuolization occurred, a sign of metabolic inhibition. The resistance of HbS gene carriers to malaria results partly from these causes of intracellular parasite death.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 78
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: The fate of extranuclear chromatin bodies (ECBs) formed by exclusion of macronuclear material at the time of karyokinesis was followed quantitatively in Tetrahymena pyriformis strain GL-I. In a logarithmic growth phase culture, 51% of the dividing cells produced one (43%) or more (8%) ECBs. Most of these gradually disappear before the next cell division, but ˜ 13% are retained and carried into subsequent cell cycles. The random distribution of ECBs into anterior or posterior daughter cells, their staining and morphological characteristics, and their rapid loss in cells in starvation medium, all indicate that ECBs play no more of a role in cellular activity than that of an internally produced food vacuole.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 79
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Patterson, D. J. 1978. Kahl's Keys to the Ciliates.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 80
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: The mechanisms regulating the development of cilia in Tetrahymena are poorly understood but might be revealed through the study of ciliogenesis mutants. Failure to regenerate cilia after dibucaine deciliation results in continued absence of motility. Therefore, to isolate ciliogenesis mutants efficiently, methods for separating motile and nonmotile cells are essential. We examined the efficacy of Ficoll underlayers for these separations. Ciliates of T. thermophila strain mpr-/mpr (6 mp sens IV) (6-methyl purine-sensitive; mating type IV) were mixed with Ficoll and added as underlayers to separatory funnels containing growth medium. At 27 C most of the cells remained motile and were found in the top layer; at 37 C, there was a time-dependent increase in the number of nonmotile cells and the number of cells in the Ficoll layer. After 150 min at 37 C, most of the cells became nonmotile and were found in the Ficoll layer. Other studies indicated that at 37 C, the cells remained alive and capable of regenerating cilia when deciliated. Thus, it is clear that the Ficoll underlayer effectively separates the majority of nonmotile cells from the majority of motile cells. Evidently, however, at 37 C wild-type T. thermophila exhibit temperature-sensitive phenotypic variability with regard to motility which should be minimized when selecting for mutations affecting motility and ciliogenesis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 81
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Colchicine has a temperature-dependent cytotoxic effect on Entamoeba sp. (Laredo isolate) that is most apparent when the drug is applied during the initiation of cultures at a concentration of 7.5 mM or higher. Continued transfer of cultures in medium containing progressively increasing concentrations of colchicine has resulted in a variant that grows prolifically in the presence of colchicine (7.5 mM) with a generation time comparable to that of the parent stock. Comparison of a number of parameters of the 2 variants revealed that colchicine resistance was accompanied by a change in cell shape, a reduced membrane permeability, which could partially be overcome by the addition of dimethyl sulfoxide (DMSO), and a reduced tolerance to osmotic stress. However, the parent strain and resistant variant were equally susceptible to cycloheximide and puromycin suggesting that the acquired colchicine resistance may not be explained on the basis of an entirely unspecific generalized reduced ability for drug uptake.Colchicine resistance and altered structure were found to be stable over a long period of time. The possible interdependence of these 2 parameters and their relation to cell motility in Entamoeba sp. are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 82
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Plasmodium cynomolgi, Plasmodium knowlesi, and Plasmodium berghei sporozoites, before and after incubation with immune serum, were studied after freeze-fracture by electron microscopy. There were evenly distributed numerous intramembranous particles (IMP) on the P face of the outer membrane. The E face of the plasma membrane had fewer IMP than its P face. The E face of the intermediate membrane had few IMP and also linear arrays of slightly raised ridges running the length of the parasite. The P face of the intermediate membrane had many IMP aligned along the long axis of the sporozoite. On the P face of the inner membrane. IMP were arranged in very distinct rows conforming to the long axis of the parasite; the E face of this membrane had a few randomly distributed IMP.A prominent change in the sporozoite incubated in immune serum was the appearance of a layer of aggregated particles around the parasite. The P face of the plasma membrane had several clear areas devoid of IMP and IMP aggregates. No changes were seen in the other fractured faces of the pellicle. These observations suggest that immune serum acts only on the P face of the plasma membrane.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 83
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Exocellular carbohydrase activity was detected, in the absence of cell lysis, in cell-free culture supernatant fluids of rumen holotrich ciliates after incubations in buffer systems of varying tonicity, from cell suspensions that were isolated by various technics, and in which bacterial activity had been suppressed by antibiotics. The kinetic characteristics of the holotrich invertases and β–glucosidase from Dasytricha, although having interspecies variations, were the same for the intra- and extracellular form of the enzyme. The properties of the invertase activity present in cell-free rumen contents resembled those of the exocellular enzymes formed by the holotrichs. Invertase activity in the in vitro culture supernatant fluid of Dasytricha ruminantium increased throughout the incubation period and was influenced by the initial pH, temperature, sucrose concentration, and inoculum size. Exocellular holotrich carbohydrase activity was increased when the incubation substrate was not readily utilized by the protozoa. Intracellular carbohydrase activity was also influenced by the carbohydrate substrate.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 84
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Phytomonas staheli sp. n. is described from the oil palm (Elaeis guineensis) and the coconut palm (Cocos nucifera) of Surinam, South America. The phytomonad is the probable cause of “Hartrot” in the coconut palm and “Marchitez sopresiva” in oil palms. Parasites are confined to the sieve tubes in palms. Some success was obtained at cultivation of the organism from Elaeis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 85
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. A new species of neogregarine, Mattesia geminata sp. n., that infects immature stages of the tropical fire ant, Solenopsis geminata (Fabricius), is described. The parasite, which develops in the hypodermis, causes disruption of the developing eyes, melanization of the cuticle, and death of pupae. lntracolonial infection rates are usually less than 2±, but may exceed 90±. Attempts to transmit the infection were unsuccessful.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 86
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Liver biopsies of white rates infected by Plasmodium berghei sporozoites were examined by electron microscopy. Intrahepatocytic schizont development was confirmed. In addition, at 60 and 70 h after sporozoite inoculation, exoerythrocytic merozoites were noted in Kupffer cells of liver sinusoids. Although it is theoretically possible that this observation may be of merozoite development in Kupffer cells, the authors suspect that this example of phagocytosis would be one of the host's natural defenses against sporozoite-transmitted malaria.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 87
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: RESUME. L'individualisation de 2 spores bicellulaires à partir d'un měme pansporoblaste caractérise la sporulation du parasite de l'Amphipode Orchestia gammarellus (Pallas) précédemment décrit sous le nom de Marteilia sp. Cette sporulation le distingue des espèces du měme genre parasite d'Huǐtres qui sont toutes caractérisées par la production de spores tricellulaires. Les conditions semblables dans lesquelles les pansporoblastes paraissent se differencier à partir d'une cellule souche dans laquelle ils poursuivent leur évolution vers la sporogenèse ainsi que divers caractères cytologiques communs, nous incitent à maintenir tous ces parasites dans une měme famille mais à placer celui de l'Amphipode dans un genre différent. Nous proposons de le nommer Paramarteilia orchestiae gen. n., sp. n.Ces parasites ne peuvent ětre maintenus dans les Protozoaires en raison de leur évolution vers la pluricellularité et de l'individualisation de ces éléments somatiques que représentent la cellule souche primaire, les pansporoblastes et cellules sporales (à l'exception des sporoplasmes). Il semble logique de les inclure dans l'embranchement des Myxozoaires créé par Grassé pour les Myxosporidies et Actinomyxidies qui différencient également des spores pluricellulaires et des éléments somatiques. Les centrioles à 9 singlets de P. orchestiae ainsi que les cellules primaires uninucléées, quel que soit le nombre de pansporoblastes qu'elles contiennent, peuvent ětre considérés comme des caractères résiduels d'Unicellulaires.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 88
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. When transformed procyclic noninfective trypanosomes of several unrelated stocks of Trypanosoma brucei were cultivated in T-30 Falcon flasks at 28 C in a liquid medium containing head-salivary gland explants of Glossina morsitans morsitans some of the organisms developed into forms infective for mice. Infective trypanosomes were detected 7 to 14 days after the cultures were prepared and they persisted for varying periods of up to 88 days when the cultures were terminated. A few of the salivary glands became invaded with parasites about the time infective organisms appeared in the cultures. Using T. brucei TREU 929, it was shown that trypanosomes grown with between 27 and 50 explants were capable of producing infections consistently for prolonged periods. On the other hand, trypanosomes cultivated with 25 or fewer explants rarely infected mice. Infectivity titrations on trypanosome suspensions from cultures of stocks TREU 1275 and TREU 929 revealed that the maximum number of infective organisms was present 26 to 50 days after initiation of the cultures. Control cultures of trypanosomes grown in medium alone were generally not infective but 2 of the 6 stocks gave rise to a few sporadic infections. A few epimastigote-like and metacyclic-like trypanosomes were seen in stained preparations of infective inocula.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 89
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Trypanosoma cruzi strain Peru was cultivated in the presence of an established cell line of Triatoma infestans embryo cells (TI-32). Bloodstream trypomastigotes differentiated into amastigote-like cells (first differentiation phase) which multiplied to form large clusters of cells. Because of their clustering nature, a new term, “staphylomastigotes,” has been proposed for this stage. After 10 days of cultivation, 90% of the staphylomastigotes underwent differentiation (2nd differentiation phase) to trypomastigotes (˜98%) or epimastigotes (˜2%). Bloodstream trypomastigotes cultivated without TI-32 cells underwent the first, but not the 2nd differentiation phase, although occasional epimastigotes were seen (〈 1%). The evidence presented suggests that TI-32 cells produce a labile factor(s) important not only for initiation of the 2nd differentiation phase but also for maintaining the parasites in the trypomastigote stage. The pH of the culture medium was not the initiating factor for the 2nd differentiation phase.Infectivity studies indicated that staphylomastigotes were as infective as bloodstream trypomastigotes, but that metacyclic trypomastigotes isolated from culture after the 2nd differentiation phase were slightly more infective than bloodstream forms.Electromicrographs of styphylomastigotes do not provide any evidence of exchange of genetic material between cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 90
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Purine nucleotide biosynthesis was studied in culture forms of Trypanosoma cruzi strain Y, Crithidia deanei (a reduviid trypanosomatid with an endosymbiote) and an aposymbiotic strain of C. deanei (obtained by curing C. deanei with chloramphenicol). Trypanosoma cruzi was found to synthesize purine nucleotides only from the preformed bases adenine and guanine (“salvage” pathway), adenine being incorporated into both adenine and guanine nucleotides. Similar results were obtained with guanine, indicating that this flagellate has a system for the interconversion of purine nucleotides. Crithidia deanei was able to synthesize purine and pyrimidine nucleotides from glycine (“de novo” pathway) and purine nucleotides from adenine and guanine (“salvage” pathway). Adenine was incorporated into both adenine and guanine nucleotides, while guanine was incorporated into guanine nucleotides only, indicating the presence of a metabolic block at the level of GMP reducaase. The aposymbiotic C. deanei strain was unable to utilize glycine for the synthesis of purine nucleotides, although glycine was utilized for synthesizing pyrimidine nucleotides. These results suggest that the endosymbiote is implicated in the de novo purine nucleotide pathway of the C. deanei-endosymbiote complex. The incorporation of adenine and guanine by aposymbiotic C. deanei strain followed a pattern similar to that observed for C. deanei.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 91
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Plasma membranes of normal duckling erythrocytes were prepared by blender homogenization and nitrogen decompression. Surface membrane vesicles of red cells infected with the avian malaria Plasmodium lophurae were produced by nitrogen decompression. Membranes of erythrocyte-free malaria parasites were removed from cytoplasmic constituents by Dounce homogenization. These membranes were collected by centrifugation in a sucrose step gradient and purified on a linear sucrose gradient. Red cell membranes had a buoyant density of 1.159 g/cm3, whereas plasmodial membranes banded at 2 densities: 1.110 g/cm3 and 1.158 g/cm3. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the isolated red cell membranes revealed 7 major protein bands with molecular weights (MW) ranging from 230,000 to 22,000, and 3 glycoprotein bands with MW of 160,000, 88,000 and 37,000. Parasite membranes also had 7 major bands with MW ranging from 100,000 to 22,000. No glycoproteins were identifiable in these membranes. The proteins of the surface membranes from infected red cells had MW similar to those from normal red cells; however, there was some evidence of a reduction in the amount of the high MW polypeptides. The red cell membrane contained 79 nmoles sialic acid/mg membrane protein, whereas plasmodial membranes had 8 nmoles sialic acid/mg membrane protein. The sialic acid content of the surface membranes of infected red cells was significantly smaller than that of normal cells. Lactoperoxidase-glucose oxidase-catalyzed iodination of intact normal and malaria-infected erythrocytes labeled 7 surface components. Although no observable differences in iodinatable proteins were seen in these preparations, there was a striking reduction in the iodinatability of erythrocytic membranes obtained from P. lophurae-infected cells. Erythrocyte-free plasmodia bound very little radioactive iodine; the small amount of radioactivity was distributed among 3 major bands with MW of 42,000, 32,000 and 28,000.It is suggested that the alterations of the surface of the P. lophurae-infected erythrocyte do not occur by a wholesale insertion of plasmodial membrane proteins into the red cell plasma membrane, but rather that there are parasite-mediated modifications of existing membrane polypeptides.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 92
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS. Mutants (NP1 and PSJ5) of Tetrahymena thermophila strains B and D 1968 exist that are unable to construct a functional oral apparatus and form food vacuoles at 37 C but which do so normally at 30 C. Food vacuole-less cells starved in dilute salt solution released similar amounts of acid phosphatase, β-N-acetyl-glucosaminidase and ±-glucosidase activity into the medium as wildtype cells during an 8-h period. Actively growing, food vacuole-less cells had ˜50% less total protein, acid phosphatase, β-N-acetyl-glucosamin-idase, and ±-glucosidase per cell than wildtype cells after 72-h growth. During this time food vacuole-less cells released significant amounts of the 3 acid hydrolases into the growth medium. For each hydrolase, the total activity released from growing, food vacuole-less cells was less, on a per cell basis, than the amount released from food vacuole formers. The proportion of the total activity secreted by the mutant and the wildtype cells was the same for acid phosphatase and β-N-acetyl-glucosaminidase and somewhat lower for ±-glucosidase. It is concluded that the release of a significant amount of acid hydrolase activity from Tetrahymena is independent of food vacuole formation and may be analogous to the secretory activity of other nonphagocytic eukaryotic cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 93
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Total numbers and distribution of genera, subgenera and species were determined for the ciliate protozoa in rumen contents of 4 Brazilian water buffalo Bubalus bubalis Linnaeus. The fauna of one animal, housed in close proximity to European and zebu-type cattle, differed considerably from that of the remaining animals, which were somewhat isolated on a large ranch. Several of the protozoan species observed in the semi-isolated animals were first described in rumen contents from humped Indian cattle, and their subsequent occurrence in other hosts and geographic locations has been limited or absent. In all, 49 different species of protozoa were found, 8 of which have not been previously described. Three of the new species belong to the genus Entodinium: E. ciculum sp. n., E. spinonucleatum sp. n. and E. triangulum sp. n.: 4 to Diplodinium (Ostracodinium): D. (O.) brazili sp. n., D. (O.) esalqum sp. n., D. (O.) nucleolobum sp. n., and D. (O.) tiete sp. n.; and one to Diplodinium (Eudiplodinium): D. (E.) bubalus sp. n.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 94
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS Two isolates of the thraustochytrid Ulkenia amoeboidea (Bahnweg & Sparrow) were obtained from the North Sea. In both isolates, the limax ameba liberated from the thallus rapidly assumed a nematode-like shape and movement characteristic of several sporozoan trophozoites. On rounding up, it underwent repeated binary fission and produced biflagellate zoospores.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 95
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS The course of Trypanosoma congolense infections in Glossina morsitans morsitans was followed by electron-microscopic examination of ultrathin sections of the guts and proboscises of infected flies. Guts dissected from flies 7 days after infection with culture procyclic forms of T. congolense had heavy trypanosome infections in the midgut involving both the endo- and ectoperitrophic spaces. Trypanosomes were also seen in the process of penetrating the fully formed peritrophic membrane in the central region of the midgut. By post infection day 21, trypanosomes had reached the proboscis of the fly and were found as clumps of epimastigote forms attached to the labrum by hemidesmosomes between their flagella and the chitinous lining of the food canal. Desmosome connections were observed between the flagella of adjacent epimastigotes. Flies examined at postinfection days 28 and 42 had, in addition to the attached forms in the labrum, free forms in the hypopharynx.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 96
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS The formation of the contractile vacuole pore (CVP) in Tetrahymena thermophila. genotype molb/molb is temporally and spatially associated with the formation of the fission gap in the CVP meridian. New CVPs arise when fission gaps appear in CVP meridians, the new pores being found anterior to the gaps. When, however, CVP meridians are rotated 180°, the fission gaps develop late. In more than 1/3 of the 180°-rotated CVP meridians, the new CVPs are formed before the appearance of the fission gap. Evidently, the appearance of the gap is not a prerequisite for CVP formation. Nevertheless, mutants exist in which the absence of fission gap and CVP are correlated in some cases and in which the presence of supernumerary fission gap and CVP are correlated in other instances. It is suggested that the 2 developmental events, although not causally related to each other, may be controlled by a common morpho-genetic signal. This commits a certain site (mid-body) along a ciliary meridian to develop the fission gap as well as the CVP; however, after this step of commitment, the appearance of the fission gap is delayed in 180°-rotated CVP meridians.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 97
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS DNA synthesis of intracellular Trypanosoma cruzi amastigotes, following the infection of bovine embryo skeletal muscle (BESM) cells, was studied by autoradiography. After penetration, there was a prereplicative lag period (∼12 h) followed by a synchronous round of DNA synthesis which was found to be independent of parasite number/BESM cell and the host cell DNA synthesis cycle. Parasite reproduction occurred, for the first time, at ∼ 21 h postinfection. It was concluded that T. cruzi trypomastigotes are in the G1/G, phase of their cell division cycle and that after penetration parasite reproduction occurs independent of events controlling host cell DNA synthesis and growth. The early synchronous growth of intracellular amastigotes should facilitate further studies on the biochemical events controlling trypomastigote-to-amastigote transformation and amastigote reproduction. A further application is envisaged for studies on the mode of action of drugs with trypanocidal activity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 98
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS The effect of cycloheximide on the experimentally induced synchronous encystment of a hypotrich ciliate, Histriculus, was examined and the cytoplasmic ultrastructures of the control and the inhibitor-treated organisms were compared. Encystment was divided into the following 5 stages based on observations of living cells: stage 1, cells with brown cytoplasm; stage 2, cells with smooth, transparent cytoplasm: stage 3, spindle-shaped cells; stage 4, spherical cells without cyst walls; and stage 5, young cysts with cyst walls. When cycloheximide treatment was preceded by stage 2, encystment and transformation into the next stages were totally blocked, whereas even in the presence of the inhibitor, stage 4 and stage 5 cells encysted normally, and stage 3 cells transformed into stage 4 although they did not form cyst walls. On the basis of ultrastructural studies it is suggested that the formation and excretion of ectocyst precursors are severely inhibited by cycloheximide and that polysome formation, active in stages 1 and 2, might be almost finished by stage 3. The role of lysosomal enzymes in the early stages of encystment are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 99
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: SYNOPSIS The babesicides imidocarb and amicarbalide, which have structural similarities to the antitrypanosomatid diamidines, proved active against Trypanosoma brucei mouse infections: both cured infections when doses were administered daily for 3 days 24 h post-inoculation (curative dose imidocarb, 10 mg/kg; amicarbalide, 25 mg/kg). Mice were considered cured after survival 30 days longer than untreated infected controls, with no trypanosomes present in blood or cerebrospinal fluid smears. Both agents also cured when administered 48 and 72 h after challenge with T. brucei and prolonged the lives of animals 94 h after challenge. The results are discussed in respect to the potential of these carbanilides and their precursors, the antitumor phthalanilides, as lead compounds in chemotherapy of mammalian trypanosomiases.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 100
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 26 (1979), S. 0 
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Wilson, R. Alan. 1979. An Introduction to Parasitology.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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