Institution
University of Marburg
Education•Marburg, Germany•
About: University of Marburg is a education organization based out in Marburg, Germany. It is known for research contribution in the topics: Population & Gene. The organization has 23195 authors who have published 42907 publications receiving 1506069 citations. The organization is also known as: Philipps University of Marburg & Philipps-Universität.
Topics: Population, Gene, Crystal structure, Laser, Catalysis
Papers published on a yearly basis
Papers
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TL;DR: Behavioral studies on mutant and transgenic flies indicate roles in spatial representation of visual cues, spatial visual memory, directional control of walking and flight, and place learning, and the data suggest that spatial azimuthal directions are represented in the slices, and cue information is represented in different layers of the central complex.
Abstract: The central complex is a group of modular neuropils across the midline of the insect brain. Hallmarks of its anatomical organization are discrete layers, an organization into arrays of 16 slices along the right-left axis, and precise inter-hemispheric connections via chiasmata. The central complex is connected most prominently with the adjacent lateral complex and the superior protocerebrum. Its developmental appearance corresponds with the appearance of compound eyes and walking legs. Distinct dopaminergic neurons control various forms of arousal. Electrophysiological studies provide evidence for roles in polarized light vision, sky compass orientation, and integration of spatial information for locomotor control. Behavioral studies on mutant and transgenic flies indicate roles in spatial representation of visual cues, spatial visual memory, directional control of walking and flight, and place learning. The data suggest that spatial azimuthal directions (i.e., where) are represented in the slices, and cu...
325 citations
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TL;DR: Quantitative evaluation of gold nanoparticles exposed to human alveolar epithelial cells at the air-liquid interface reveals that NP surface coatings modulate endocytotic uptake pathways and cellular NP trafficking.
Abstract: This study addresses the cellular uptake and intracellular trafficking of 15-nm gold nanoparticles (NPs), either plain (i.e., stabilized with citrate) or coated with polyethylene glycol (PEG), exposed to human alveolar epithelial cells (A549) at the air-liquid interface for 1, 4, and 24 h. Quantitative analysis by stereology on transmission electron microscopy images reveals a significant, nonrandom intracellular distribution for both NP types. No particles are observed in the nucleus, mitochondria, endoplasmic reticulum, or golgi. The cytosol is not a preferred cellular compartment for both NP types, although significantly more PEG-coated than citrate-stabilized NPs are present there. The preferred particle localizations are vesicles of different sizes ( 1000 nm). This is observed for both NP types and indicates a predominant uptake by endocytosis. Subsequent inhibition of caveolin- and clathrin-mediated endocytosis by methyl-beta-cyclodextrin (MbetaCD) results in a significant reduction of intracellular NPs. The inhibition, however, is more pronounced for PEG-coated than citrate-stabilized NPs. The latter are mostly found in larger vesicles; therefore, they are potentially taken up by macropinocytosis, which is not inhibited by MbetaCD. With prolonged exposure times, both NPs are preferentially localized in larger-sized intracellular vesicles such as lysosomes, thus indicating intracellular particle trafficking. This quantitative evaluation reveals that NP surface coatings modulate endocytotic uptake pathways and cellular NP trafficking. Other nonendocytotic entry mechanisms are found to be involved as well, as indicated by localization of a minority of PEG-coated NPs in the cytosol.
325 citations
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TL;DR: An update on the current understanding of adenoid cystic carcinoma of the head and neck is provided, including a review of its epidemiology, clinical behavior, pathology, molecular biology, diagnostic workup, treatment and prognosis.
325 citations
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TL;DR: A taxonomy of mixed-methods designs has been proposed in this paper, but there is a lack of agreement regarding basic concepts and definitions, as is bemoaned by many experts in this field.
Abstract: Despite ongoing ‘paradigm wars’ between the methodological traditions of qualitative and quantitative research, ‘mixed methods’ represents nowadays a rapidly developing field of social science methodology. In such discussions it is often emphasized that the use of methods should be predominantly influenced by substantive research questions, and not only by methodological and epistemological considerations. As all methods have specific limitations as well as particular strengths, many discussants propose that qualitative and quantitative methods should be combined in order to compensate for their mutual and overlapping weaknesses. However, although a variety of proposals have been made for a taxonomy of mixed-methods designs, there is yet a lack of agreement regarding basic concepts and definitions, as is bemoaned by many experts in this field. This lack of common ground is due to the fact that crucial questions regarding the relations between research domains and methods have been not sufficiently discuss...
324 citations
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TL;DR: Intercompartmental DNA transfer represents a significant driving force for gene and genome evolution, relocating and refashioning genes and contributing to genetic diversity.
Abstract: In eukaryotes, DNA is exchanged between endosymbiosis-derived compartments (mitochondria and chloroplasts) and the nucleus. Organelle-to-nucleus DNA transfer involves repair of double-stranded breaks by nonhomologous end-joining, and resulted during early organelle evolution in massive relocation of organelle genes to the nucleus. A large fraction of the products of the nuclear genes so acquired are retargeted to their ancestral compartment; many others now function in new subcellular locations. Almost all present-day nuclear transfers of mitochondrial or plastid DNA give rise to noncoding sequences, dubbed nuclear mitochondrial DNAs (NUMTs) and nuclear plastid DNAs (NUPTs). Some of these sequences were recruited as exons, thus introducing new coding sequences into preexisting nuclear genes by a novel mechanism. In organisms derived from secondary or tertiary endosymbiosis, serial gene transfers involving nucleus-to-nucleus migration of DNA have also occurred. Intercompartmental DNA transfer therefore rep...
324 citations
Authors
Showing all 23488 results
Name | H-index | Papers | Citations |
---|---|---|---|
John C. Morris | 183 | 1441 | 168413 |
Russel J. Reiter | 169 | 1646 | 121010 |
Martin J. Blaser | 147 | 820 | 104104 |
Christopher T. Walsh | 139 | 819 | 74314 |
Markus Cristinziani | 131 | 1140 | 84538 |
James C. Paulson | 126 | 443 | 52152 |
Markus F. Neurath | 124 | 934 | 62376 |
Nicholas W. Wood | 123 | 614 | 66270 |
Florian Lang | 116 | 1421 | 66496 |
Howard I. Maibach | 116 | 1821 | 60765 |
Thomas G. Ksiazek | 113 | 398 | 46108 |
Frank Glorius | 113 | 663 | 49305 |
Eberhard Ritz | 111 | 1109 | 61530 |
Manfred T. Reetz | 110 | 959 | 42941 |
Wolfgang H. Oertel | 110 | 653 | 51147 |