22 research outputs found

    Die Geschichte der VeterinÀrmedizinischen FakultÀt der UniversitÀt Leipzig von 1923 bis 1933

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    Die vorliegende Arbeit versteht sich als ein Beitrag zur wissenschaftlichen Bearbeitung der Geschichte der VeterinĂ€rmedizinischen FakultĂ€t der UniversitĂ€t Leipzig und behandelt das erste Jahrzehnt ihres Bestehens, also den Zeitraum von 1923 bis 1933. Als Grundlage der Dokumentation dienten hauptsĂ€chlich Archivalien. Des Weiteren wurden zeitgenössische Fachzeitschriften verwendet. Zur Darstellung des zeitgeschichtlichen Hintergrundes wurden hauptsĂ€chlich SekundĂ€rliteratur sowie einige wenige Internetseiten verwendet. Die Ergebnisse sind in zwei Abschnitte untergliedert, dabei befasst sich der erste Abschnitt mit der GesamtfakultĂ€t, wĂ€hrend der zweite Abschnitt nĂ€her auf die einzelnen Institute und Kliniken eingeht. Die Gesamtsituation war stark geprĂ€gt vom Umzug der TierĂ€rztlichen Hochschule Dresden nach Leipzig und der damit verbundenen Eingliederung in die Leipziger Alma mater. Desweiteren verursachte die wirtschaftliche Notlage erhebliche Probleme fĂŒr Forschung und Lehre. Dies ist auch im zweiten Abschnitt bei der Besprechung der einzelnen Einrichtungen an der FakultĂ€t ein allgegenwĂ€rtiges Thema. Des Weiteren wird auf die Dozenten der Institute und Kliniken eingegangen, soweit diese nicht bereits Gegenstand anderer Dissertationen waren. Die wichtigsten Forschungsarbeiten und – soweit anhand von Archivalien belegbar – die Geldgeber dafĂŒr werden ebenfalls fĂŒr die meisten Einrichtungen der FakultĂ€t aufgezeigt. In der anschließenden Diskussion werden zunĂ€chst die Vor- und Nachteile des Umzuges von Dresden nach Leipzig gegenĂŒbergestellt. Obwohl die Nachteile hierbei zu ĂŒberwiegen scheinen, kommt die Autorin zu dem Schluss, dass es nicht der Umzug an sich war, der sich als nachteilig erwies, sondern die wirtschaftlichen Bedingungen nach dem 1. Weltkrieg, welche den Umzug zu einer regelrechten BewĂ€hrungsprobe machten. Weiterhin wird diskutiert, ob es unter den gegebenen UmstĂ€nden möglich war, freie Forschung zu betreiben. Hier wird deutlich, dass diese Möglichkeit zwar theoretisch gegeben war, praktisch jedoch waren diejenigen Forscher, welche sich mit Themen beschĂ€ftigten, die das Interesse des Staates und/oder der Industrie weckten, weitaus besser gestellt und konnten ihre Forschungen entsprechend schnell vorantreiben. Als Beispiel sei hier Arthur SCHEUNERT genannt, der sich hauptsĂ€chlich mit Vitaminforschungen beschĂ€ftigte. Forschungen, fĂŒr die der Staat bzw. die Industrie keine bzw. nur wenige Gelder aufbringen konnten oder wollten, waren dagegen nur möglich, weil sich Leiter und Mitarbeiter der Institute unter Erbringung persönlicher finanzieller und zeitlicher Opfer dafĂŒr einsetzten, wie beispielsweise Herman BAUM und sein PrĂ€parator Paul KURZWEG.This paper should be understood as one article regarding the scientific processing of the history of the Faculty for Veterinary Medicine at the University of Leipzig. The paper presents the first decade of its existence, meaning the time period from 1923 to 1933. The archives have served primarily as the foundation of the documentation. Furthermore, contemporary technical journals have been used. Secondary literature and a few Internet pages have also been primarily used for the presentation of the historical background. The results have been sub-divided into two sections, whereby the first section deals with the overall faculty, while the second section addresses the details of the individual institutes and clinics. The overall situation was strongly characterized by the relocation of the College of Veterinary Medicine, Dresden, and its incorporation into the University of Leipzig. Furthermore, the economic necessity caused significant problems for research work and teaching. This is also a ubiquitous topic in the second section as part of the discussion of the individual establishments of the faculty. Furthermore, insofar as such has not been the topic of other dissertations, the lecturers at the institutes and clinics will be discussed. The most important research projects and, to the extent such can be proven on the basis of the archives, the sponsors for such projects will also be presented for most of the establishments of the faculty. The advantages and disadvantages of the relocation from Dresden to Leipzig will first be contrasted in the subsequent discussion. Although the disadvantages of this would seem to prevail, the author has concluded that the relocation itself was not the true disadvantages, but rather the economic conditions after the First World War, which made the relocation into a real test. Furthermore, if it would have been possible to conduct research freely under the circumstances will also be discussed. The fact that this possibility was entirely possible in theory, however those researchers who investigated these issues and wakened the interests of the state and/or the industry were much more capable of expediting their own research more quickly will be made clear. Arthur SCHEUNERT, who primarily performed vitamin research, would be one example. Research projects that either the state or industry could not, or did not, want to support financially were only possible, because the leaders and employees of the institutes invested their own money and time, as exemplified by Herman BAUM and his preparatory, Paul KURZWEG

    Engineered polysaccharides: α‐1,3‐glucan acetates showing upper critical solution temperature in organic solvents

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    Abstract Acetates of α‐1,3‐glucan dissolved in N , N ‐dimethyl acetamide/LiCl are prepared by converting the polysaccharide with acetyl chloride, acetic acid anhydride/pyridine, or with acetic acid/ N,N â€Č‐carbonyl diimidazole. Values of the degree of substitution for the acetyl groups (DS Ac ) of up to 2.6 are realized. NMR spectroscopic measurements reveal a preferred conversion of the primary hydroxyl group at position 6 followed by positions 2 and 4. Depending on the DS Ac , the samples may be soluble in solvents of different polarity at room temperature or at elevated temperatures showing upper critical solution temperature at DS of about 2.5. This process is found to be reversible

    Bacteria-responsive multilayer coatings comprising polycationic nanospheres for bacteria biofilm prevention on urinary catheters

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    This work reports on the development of infection-preventive coatings on silicone urinary catheters that contain in their structure and release on demand antibacterial polycationic nanospheres. Polycationic aminocellulose conjugate was first sonochemically processed into nanospheres to improve its antibacterial potential compared to the bulk conjugate in solution (ACSol). Afterwards the processed aminocellulose nanospheres (ACNSs) were combined with the hyaluronic acid (HA) polyanion to build a layer-by-layer construct on silicone surfaces. Although the coating deposition was more effective when HA was coupled with ACSol than with ACNSs, the ACNSs-based coatings were thicker and displayed smoother surfaces due to the embedment of intact nanospheres. The antibacterial effect of the ACNSs multilayers was by 40 % higher compared to the ACSol coatings. This fact was further translated into more effective prevention of Pseudomonas aeruginosa biofilm formation. The coatings were stable in absence of bacteria, whereas their disassembling occurred gradually during incubation with Pseudomonas aeruginosa, and thus eradicate the biofilm upon release of antibacterial agents. Only 5 bilayers of HA/ACNSs were sufficient to prevent the biofilm formation, in contrast to the 10 bilayers of ACSol required to achieve the same effect. The antibiofilm efficiency of (HA/ACNSs)10 multilayer construct built on a Foley catheter was additionally validated under dynamic conditions using a model of catheterized bladder in which the biofilm was grown during seven days.M.M.F. acknowledges the support of the European Commissionunder the Marie Curie Intra-European Fellowship (IEF) Program (Grant Agreement ‘‘NanoQuench” FP7-331416)

    The representation of motor (inter)action, states of action, and learning: Three perspectives on motor learning by way of imagery and execution

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    Frank C, Schack T. The representation of motor (inter)action, states of action, and learning: Three perspectives on motor learning by way of imagery and execution. Frontiers in Psychology. 2017;8: 678.Learning in intelligent systems is a result of direct and indirect interaction with the environment. While humans can learn by way of different states of (inter)action such as the execution or the imagery of an action, their unique potential to induce brain- and mind-related changes in the motor action system is still being debated. The systematic repetition of different states of action (e.g., physical and/or mental practice) and their contribution to the learning of complex motor actions has traditionally been approached by way of performance improvements. More recently, approaches highlighting the role of action representation in the learning of complex motor actions have evolved and may provide additional insight into the learning process. In the present perspective paper, we build on brain-related findings and sketch recent research on learning by way of imagery and execution from a hierarchical, perceptual-cognitive approach to motor control and learning. These findings provide insights into the learning of intelligent systems from a perceptual-cognitive, representation-based perspective and as such add to our current understanding of action representation in memory and its changes with practice. Future research should build bridges between approaches in order to more thoroughly understand functional changes throughout the learning process and to facilitate motor learning, which may have particular importance for cognitive systems research in robotics, rehabilitation, and sports

    Die Geschichte der VeterinÀrmedizinischen FakultÀt der UniversitÀt Leipzig von 1923 bis 1933

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    Die vorliegende Arbeit versteht sich als ein Beitrag zur wissenschaftlichen Bearbeitung der Geschichte der VeterinĂ€rmedizinischen FakultĂ€t der UniversitĂ€t Leipzig und behandelt das erste Jahrzehnt ihres Bestehens, also den Zeitraum von 1923 bis 1933. Als Grundlage der Dokumentation dienten hauptsĂ€chlich Archivalien. Des Weiteren wurden zeitgenössische Fachzeitschriften verwendet. Zur Darstellung des zeitgeschichtlichen Hintergrundes wurden hauptsĂ€chlich SekundĂ€rliteratur sowie einige wenige Internetseiten verwendet. Die Ergebnisse sind in zwei Abschnitte untergliedert, dabei befasst sich der erste Abschnitt mit der GesamtfakultĂ€t, wĂ€hrend der zweite Abschnitt nĂ€her auf die einzelnen Institute und Kliniken eingeht. Die Gesamtsituation war stark geprĂ€gt vom Umzug der TierĂ€rztlichen Hochschule Dresden nach Leipzig und der damit verbundenen Eingliederung in die Leipziger Alma mater. Desweiteren verursachte die wirtschaftliche Notlage erhebliche Probleme fĂŒr Forschung und Lehre. Dies ist auch im zweiten Abschnitt bei der Besprechung der einzelnen Einrichtungen an der FakultĂ€t ein allgegenwĂ€rtiges Thema. Des Weiteren wird auf die Dozenten der Institute und Kliniken eingegangen, soweit diese nicht bereits Gegenstand anderer Dissertationen waren. Die wichtigsten Forschungsarbeiten und – soweit anhand von Archivalien belegbar – die Geldgeber dafĂŒr werden ebenfalls fĂŒr die meisten Einrichtungen der FakultĂ€t aufgezeigt. In der anschließenden Diskussion werden zunĂ€chst die Vor- und Nachteile des Umzuges von Dresden nach Leipzig gegenĂŒbergestellt. Obwohl die Nachteile hierbei zu ĂŒberwiegen scheinen, kommt die Autorin zu dem Schluss, dass es nicht der Umzug an sich war, der sich als nachteilig erwies, sondern die wirtschaftlichen Bedingungen nach dem 1. Weltkrieg, welche den Umzug zu einer regelrechten BewĂ€hrungsprobe machten. Weiterhin wird diskutiert, ob es unter den gegebenen UmstĂ€nden möglich war, freie Forschung zu betreiben. Hier wird deutlich, dass diese Möglichkeit zwar theoretisch gegeben war, praktisch jedoch waren diejenigen Forscher, welche sich mit Themen beschĂ€ftigten, die das Interesse des Staates und/oder der Industrie weckten, weitaus besser gestellt und konnten ihre Forschungen entsprechend schnell vorantreiben. Als Beispiel sei hier Arthur SCHEUNERT genannt, der sich hauptsĂ€chlich mit Vitaminforschungen beschĂ€ftigte. Forschungen, fĂŒr die der Staat bzw. die Industrie keine bzw. nur wenige Gelder aufbringen konnten oder wollten, waren dagegen nur möglich, weil sich Leiter und Mitarbeiter der Institute unter Erbringung persönlicher finanzieller und zeitlicher Opfer dafĂŒr einsetzten, wie beispielsweise Herman BAUM und sein PrĂ€parator Paul KURZWEG.This paper should be understood as one article regarding the scientific processing of the history of the Faculty for Veterinary Medicine at the University of Leipzig. The paper presents the first decade of its existence, meaning the time period from 1923 to 1933. The archives have served primarily as the foundation of the documentation. Furthermore, contemporary technical journals have been used. Secondary literature and a few Internet pages have also been primarily used for the presentation of the historical background. The results have been sub-divided into two sections, whereby the first section deals with the overall faculty, while the second section addresses the details of the individual institutes and clinics. The overall situation was strongly characterized by the relocation of the College of Veterinary Medicine, Dresden, and its incorporation into the University of Leipzig. Furthermore, the economic necessity caused significant problems for research work and teaching. This is also a ubiquitous topic in the second section as part of the discussion of the individual establishments of the faculty. Furthermore, insofar as such has not been the topic of other dissertations, the lecturers at the institutes and clinics will be discussed. The most important research projects and, to the extent such can be proven on the basis of the archives, the sponsors for such projects will also be presented for most of the establishments of the faculty. The advantages and disadvantages of the relocation from Dresden to Leipzig will first be contrasted in the subsequent discussion. Although the disadvantages of this would seem to prevail, the author has concluded that the relocation itself was not the true disadvantages, but rather the economic conditions after the First World War, which made the relocation into a real test. Furthermore, if it would have been possible to conduct research freely under the circumstances will also be discussed. The fact that this possibility was entirely possible in theory, however those researchers who investigated these issues and wakened the interests of the state and/or the industry were much more capable of expediting their own research more quickly will be made clear. Arthur SCHEUNERT, who primarily performed vitamin research, would be one example. Research projects that either the state or industry could not, or did not, want to support financially were only possible, because the leaders and employees of the institutes invested their own money and time, as exemplified by Herman BAUM and his preparatory, Paul KURZWEG

    Die Geschichte der VeterinÀrmedizinischen FakultÀt der UniversitÀt Leipzig von 1923 bis 1933

    Get PDF
    Die vorliegende Arbeit versteht sich als ein Beitrag zur wissenschaftlichen Bearbeitung der Geschichte der VeterinĂ€rmedizinischen FakultĂ€t der UniversitĂ€t Leipzig und behandelt das erste Jahrzehnt ihres Bestehens, also den Zeitraum von 1923 bis 1933. Als Grundlage der Dokumentation dienten hauptsĂ€chlich Archivalien. Des Weiteren wurden zeitgenössische Fachzeitschriften verwendet. Zur Darstellung des zeitgeschichtlichen Hintergrundes wurden hauptsĂ€chlich SekundĂ€rliteratur sowie einige wenige Internetseiten verwendet. Die Ergebnisse sind in zwei Abschnitte untergliedert, dabei befasst sich der erste Abschnitt mit der GesamtfakultĂ€t, wĂ€hrend der zweite Abschnitt nĂ€her auf die einzelnen Institute und Kliniken eingeht. Die Gesamtsituation war stark geprĂ€gt vom Umzug der TierĂ€rztlichen Hochschule Dresden nach Leipzig und der damit verbundenen Eingliederung in die Leipziger Alma mater. Desweiteren verursachte die wirtschaftliche Notlage erhebliche Probleme fĂŒr Forschung und Lehre. Dies ist auch im zweiten Abschnitt bei der Besprechung der einzelnen Einrichtungen an der FakultĂ€t ein allgegenwĂ€rtiges Thema. Des Weiteren wird auf die Dozenten der Institute und Kliniken eingegangen, soweit diese nicht bereits Gegenstand anderer Dissertationen waren. Die wichtigsten Forschungsarbeiten und – soweit anhand von Archivalien belegbar – die Geldgeber dafĂŒr werden ebenfalls fĂŒr die meisten Einrichtungen der FakultĂ€t aufgezeigt. In der anschließenden Diskussion werden zunĂ€chst die Vor- und Nachteile des Umzuges von Dresden nach Leipzig gegenĂŒbergestellt. Obwohl die Nachteile hierbei zu ĂŒberwiegen scheinen, kommt die Autorin zu dem Schluss, dass es nicht der Umzug an sich war, der sich als nachteilig erwies, sondern die wirtschaftlichen Bedingungen nach dem 1. Weltkrieg, welche den Umzug zu einer regelrechten BewĂ€hrungsprobe machten. Weiterhin wird diskutiert, ob es unter den gegebenen UmstĂ€nden möglich war, freie Forschung zu betreiben. Hier wird deutlich, dass diese Möglichkeit zwar theoretisch gegeben war, praktisch jedoch waren diejenigen Forscher, welche sich mit Themen beschĂ€ftigten, die das Interesse des Staates und/oder der Industrie weckten, weitaus besser gestellt und konnten ihre Forschungen entsprechend schnell vorantreiben. Als Beispiel sei hier Arthur SCHEUNERT genannt, der sich hauptsĂ€chlich mit Vitaminforschungen beschĂ€ftigte. Forschungen, fĂŒr die der Staat bzw. die Industrie keine bzw. nur wenige Gelder aufbringen konnten oder wollten, waren dagegen nur möglich, weil sich Leiter und Mitarbeiter der Institute unter Erbringung persönlicher finanzieller und zeitlicher Opfer dafĂŒr einsetzten, wie beispielsweise Herman BAUM und sein PrĂ€parator Paul KURZWEG.This paper should be understood as one article regarding the scientific processing of the history of the Faculty for Veterinary Medicine at the University of Leipzig. The paper presents the first decade of its existence, meaning the time period from 1923 to 1933. The archives have served primarily as the foundation of the documentation. Furthermore, contemporary technical journals have been used. Secondary literature and a few Internet pages have also been primarily used for the presentation of the historical background. The results have been sub-divided into two sections, whereby the first section deals with the overall faculty, while the second section addresses the details of the individual institutes and clinics. The overall situation was strongly characterized by the relocation of the College of Veterinary Medicine, Dresden, and its incorporation into the University of Leipzig. Furthermore, the economic necessity caused significant problems for research work and teaching. This is also a ubiquitous topic in the second section as part of the discussion of the individual establishments of the faculty. Furthermore, insofar as such has not been the topic of other dissertations, the lecturers at the institutes and clinics will be discussed. The most important research projects and, to the extent such can be proven on the basis of the archives, the sponsors for such projects will also be presented for most of the establishments of the faculty. The advantages and disadvantages of the relocation from Dresden to Leipzig will first be contrasted in the subsequent discussion. Although the disadvantages of this would seem to prevail, the author has concluded that the relocation itself was not the true disadvantages, but rather the economic conditions after the First World War, which made the relocation into a real test. Furthermore, if it would have been possible to conduct research freely under the circumstances will also be discussed. The fact that this possibility was entirely possible in theory, however those researchers who investigated these issues and wakened the interests of the state and/or the industry were much more capable of expediting their own research more quickly will be made clear. Arthur SCHEUNERT, who primarily performed vitamin research, would be one example. Research projects that either the state or industry could not, or did not, want to support financially were only possible, because the leaders and employees of the institutes invested their own money and time, as exemplified by Herman BAUM and his preparatory, Paul KURZWEG

    FUNCTIONALIZATION PATTERN OF TERT-BUTYLDIMETHYL-SILYL CELLULOSE EVALUATED BY NMR SPECTROSCOPY

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    Tert-butyldimethylsilyl cellulose with a degree of substitution (DS) of up to 2 could be obtained by homogeneous conversion of the biopolymer with tert-butylchlorosilane in N,N-dimethyl aceteamide/LiCl in the presence of imidazole. The cellulose derivatives were characterized in detail by means of two-dimensional NMR spectroscopic techniques including subsequent derivatization of the original polymer by consecutive methylation-desilyation-acetylation. The very well resolved NMR spectra indicate that dependent on the reaction temperature 2,6-di-O-tert-butyldimethylsilyl moieties are the main repeating units. 3,6-di-O- and 6-mono-O functionalized repeating units were identified in very small amount if the reaction is carried out at room temperature. Additionally, 2,3,6-tri-O-silylated functions appear if reaction is carried out at temperature of 100°C. Thus, a novel path for regioselective protection of position 2 and 6 for cellulose was established

    Fluorescent multifunctional polysaccharides for sustainable supramolecular functionalization of fibers in water

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    © 2016 American Chemical Society. The paper describes the synthesis of multifunctional cellulose derivatives (MCDs) containing a fluorescent and a cationic moiety and their application in the functionalization of pulp fibers. The cellulose derivatives, namely N-(3-propanoic acid)-and N-(4-butanoic acid)-1,8-naphthalimide esters of cellulose, differed in the degree of substitution (DS) and by the aliphatic chain connecting naphthalimide photoactive groups to the polymer backbone. The derivatives were decorated with a cationic moiety, namely (3-carboxypropyl)trimethylammonium chloride. The fluorescent pulp fibers were prepared by direct self-assembly of the water-soluble fluorescent MCDs on the fibers in water at room temperature. The results indicated that the adsorption was mainly driven by an ion exchange mechanism. UV-vis and fluorescence spectroscopic studies showed that the adsorption yield of the fluorescent MCDs depended on the length of the aliphatic chain of the photoactive groups. Because of the adsorption, the modified pulp fibers gained fluorescence in the visible part of the spectrum. Under black light illumination, the modified fibers fluoresced, which made them visually distinguishable from the reference fibers. Thus, the fluorescent pulp fibers prepared in a simple way can be potentially used as an authenticity indicator in packaging materials.status: publishe

    Engineered Polysaccharides: α‐1,3‐Glucan Acetates Showing Upper Critical Solution Temperature in Organic Solvents

    No full text
    Abstract Acetates of α‐1,3‐glucan dissolved in N , N ‐dimethyl acetamide/LiCl are prepared by converting the polysaccharide with acetyl chloride, acetic acid anhydride/pyridine, or with acetic acid/ N,N â€Č‐carbonyl diimidazole. Values of the degree of substitution for the acetyl groups (DS Ac ) of up to 2.6 are realized. NMR spectroscopic measurements reveal a preferred conversion of the primary hydroxyl group at position 6 followed by positions 2 and 4. Depending on the DS Ac , the samples may be soluble in solvents of different polarity at room temperature or at elevated temperatures showing upper critical solution temperature at DS of about 2.5. This process is found to be reversible
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