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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Single-Copy Nuclear Genes Place Haustorial Hydnoraceae within Piperales and Reveal a Cretaceous Origin of Multiple Parasitic Angiosperm Lineages

Naumann, Julia, Salomo, Karsten, Der, Joshua P., Wafula, Eric K., Bolin, Jay F., Maass, Erika, Frenzke, Lena, Samain, Marie-Stéphanie, Neinhuis, Christoph, dePamphilis, Claude W., Wanke, Stefan 06 February 2014 (has links)
Extreme haustorial parasites have long captured the interest of naturalists and scientists with their greatly reduced and highly specialized morphology. Along with the reduction or loss of photosynthesis, the plastid genome often decays as photosynthetic genes are released from selective constraint. This makes it challenging to use traditional plastid genes for parasitic plant phylogenetics, and has driven the search for alternative phylogenetic and molecular evolutionary markers. Thus, evolutionary studies, such as molecular clock-based age estimates, are not yet available for all parasitic lineages. In the present study, we extracted 14 nuclear single copy genes (nSCG) from Illumina transcriptome data from one of the “strangest plants in the world”, Hydnora visseri (Hydnoraceae). A ~15,000 character molecular dataset, based on all three genomic compartments, shows the utility of nSCG for reconstructing phylogenetic relationships in parasitic lineages. A relaxed molecular clock approach with the same multi-locus dataset, revealed an ancient age of ~91 MYA for Hydnoraceae. We then estimated the stem ages of all independently originated parasitic angiosperm lineages using a published dataset, which also revealed a Cretaceous origin for Balanophoraceae, Cynomoriaceae and Apodanthaceae. With the exception of Santalales, older parasite lineages tend to be more specialized with respect to trophic level and have lower species diversity. We thus propose the “temporal specialization hypothesis” (TSH) implementing multiple independent specialization processes over time during parasitic angiosperm evolution.
222

Work-related complaints and diseases of physical therapists – protocol for the establishment of a “Physical Therapist Cohort” (PTC) in Germany

Girbig, Maria, Deckert, Stefanie, Kopkow, Christian, Latza, Ute, Dulon, Madeleine, Nienhaus, Albert, Groneberg, David, Seidler, Andreas 07 July 2014 (has links)
Background: Only few studies deal with the workload of physical therapists and the health consequences, although this occupational group is quite important for the health care system in many industrialized countries (e.g. ca. 136 000 people are currently employed as physical therapists in Germany). Therefore, the current state of knowledge of work-related diseases and disorders of physical therapists is insufficient. The aim of the 'Physical Therapist Cohort' (PTC) study is to analyze the association between work-related exposures and diseases among physical therapists in Germany. This article describes the protocol of the baseline assessment of the PTC study. Methods/Design: A cross-sectional study will be conducted as baseline assessment and will include a representative random sample of approximately 300 physical therapists employed in Germany (exposure group), and a population-based comparison group (n = 300). The comparison group will comprise a sample of working aged (18–65 years) inhabitants of a German city. Variables of interest will be assessed using a questionnaire manual including questions regarding musculoskeletal, dermal, and infectious diseases and disorders as well as psychosocial exposures, diseases and disorders. In addition to subjective measures, a clinical examination will be used to objectify the questionnaire-based results (n = 50). Discussion: The study, which includes extensive data collection, provides a unique opportunity to study the prospective association of work-related exposures and associated complaints of physical therapists. Baseline results will give first clues with regard to whether and how prevalent main exposures of physiotherapeutic work and typical work areas of physical therapists are associated with the development of work-related diseases. Thereby, this baseline assessment provides the basis for further investigations to examine causal relationships in accordance with a longitudinal design.
223

Phenotypic Variability in a Family with Aicardi-Goutières Syndrome Due to the Common A177T RNASEH2B Mutation

Tüngler, Victoria, Schmidt, Franziska, Hieronimus, Steve, Reyes-Velasco, Claudio, Lee-Kirsch, Min Ae 09 July 2014 (has links)
Aicardi-Goutières syndrome (AGS) is a rare inflammatory encephalopathy mimicking in utero acquired viral infection. Cardinal findings comprise leukodystrophy, basal ganglia calcifications and cerebral atrophy along with cerebrospinal fluid lymphocytosis and elevated interferon-α. In the majority of cases AGS is inherited as an autosomal recessive trait and caused by mutations in six genes including RNASEH2A, RNASEH2B, RNASEH2C, TREX1, SAMHD1 and ADAR1, all of which encode enzymes acting on nucleic acid species. Most patients present with first neurological signs in early infancy and experience severe global developmental delay. Here, we report on the unusual divergent phenotype of two siblings who both carry the most frequent AGS causing p.A177T (c.529G > A) RNASEH2B mutation in the homozygous state. While one sibling showed a typical AGS presentation with early onset and severe statomotor and mental impairment, the older sibling was intellectually completely normal. She was only diagnosed because of mild spasticity of the legs and serological signs of autoimmunity. These findings highlight the phenotypic variability of AGS and suggest that AGS may be underdiagnosed among children with mild cerebral palsy.
224

Artificial Extracellular Matrices with Oversulfated Glycosaminoglycan Derivatives Promote the Differentiation of Osteoblast-Precursor Cells and Premature Osteoblasts

Hempel, Ute, Preissler, Carolin, Vogel, Sarah, Möller, Stephanie, Hintze, Vera, Becher, Jana, Schnabelrauch, Matthias, Rauner, Martina, Hofbauer, Lorenz C., Dieter, Peter 07 May 2015 (has links)
Sulfated glycosaminoglycans (GAG) are components of the bone marrow stem cell niche and to a minor extent of mature bone tissue with important functions in regulating stem cell lineage commitment and differentiation. We anticipated that artificial extracellular matrices (aECM) composed of collagen I and synthetically oversulfated GAG derivatives affect preferentially the differentiation of osteoblast-precursor cells and early osteoblasts. A set of gradually sulfated chondroitin sulfate and hyaluronan derivatives was used for the preparation of aECM. All these matrices were analysed with human bone marrow stromal cells to identify the most potent aECM and to determine the influence of the degree and position of sulfate groups and the kind of disaccharide units on the osteogenic differentiation. Oversulfated GAG derivatives with a sulfate group at the C-6 position of the N-acetylglycosamine revealed the most pronounced proosteogenic effect as determined by tissue nonspecific alkaline phosphatase activity and calcium deposition. A subset of the aECM was further analysed with different primary osteoblasts and cell lines reflecting different maturation stages to test whether the effect of sulfated GAG derivatives depends on the maturation status of the cells. It was shown that the proosteogenic effect of aECMwasmost prominent in early osteoblasts. [ABSTRACT FROM AUTHOR]
225

Division of Labour and Self-Reported Mental Requirements in Human Services: Retail Sale Jobs

Pietrzyk, Ulrike, Rodehacke, Sarah, Hacker, Winfried 07 May 2015 (has links)
Significant associations between self-reported “whole units” of work and self-reported mental task requirements as well as personal outcomes are well known. Also of interest is, however, whether a significant association also exists between the underlying objective assignment of tasks, i.e. the division of labour, and self-reported mental requirements. Such an association would represent a concrete starting point for job design or redesign. We analyzed this question for retail sale jobs as an example of the numerous human service jobs, which usually consist of customer- and object-centred tasks. The study (N = 558 employees) evaluated the potential association between documented assignments of customer-centred and goods-centred activities and employees’ perceived mental requirements, skill utilisation, and learning on the job, as well as mental difficulties. A significant association of moderate effect size between the objective division of labour and self-reported mental job requirements was shown. Theoretical and practical consequences of this association are also discussed.
226

Neural mechanisms of goal-directed behavior: outcome-based response selection is associated with increased functional coupling of the angular gyrus

Zwosta, Katharina, Ruge, Hannes, Wolfensteller, Uta 24 July 2015 (has links)
Goal-directed behavior is based on representations of contingencies between a certain situation (S), a certain (re)action (R) and a certain outcome (O). These S-R-O representations enable flexible response selection in different situations according to the currently pursued goal. Importantly however, the successful formation of such representations is a necessary but not sufficient precondition for goal-directed behavior which additionally requires the actual usage of the contingency information for action control. The present fMRI study aimed at identifying the neural basis of each of these two aspects: representing vs. explicitly using experienced S-R-O contingencies. To this end, we created three experimental conditions: S-R-O contingency present and used for outcome-based response selection, S-R-O contingency present but not used, and S-R-O contingency absent. The comparison between conditions with and without S-R-O contingency revealed that the angular gyrus is relevant for representing S-R-O contingencies. The explicit usage of learnt S-R-O representations in turn was associated with increased functional coupling between angular gyrus and several subcortical (hippocampus, caudate head), prefrontal (lateral orbitofrontal cortex (OFC), rostrolateral prefrontal cortex (RLPFC)) and cerebellar areas, which we suggest represent different explicit and implicit processes of goal-directed action control. Hence, we ascribe a central role to the angular gyrus in associating actions to their sensory outcomes which is used to guide behavior through coupling of the angular gyrus with multiple areas related to different aspects of action control.
227

HAEC News

January 2013 (has links)
No description available.
228

HAEC News

06 September 2013 (has links) (PDF)
No description available.
229

HAEC News

06 September 2013 (has links) (PDF)
No description available.
230

Precursor Lesions for Sporadic Pancreatic Cancer: PanIN, IPMN, and MCN

Distler, Marius, Aust, Daniela E., Weitz, Jürgen, Pilarsky, Christian, Grützmann, Robert 11 July 2014 (has links) (PDF)
Pancreatic cancer is still a dismal disease. The high mortality rate is mainly caused by the lack of highly sensitive and specific diagnostic tools, and most of the patients are diagnosed in an advanced and incurable stage. Knowledge about precursor lesions for pancreatic cancer has grown significantly over the last decade, and nowadays we know that mainly three lesions (PanIN, and IPMN, MCN) are responsible for the development of pancreatic cancer. The early detection of these lesions is still challenging but provides the chance to cure patients before they might get an invasive pancreatic carcinoma. This paper focuses on PanIN, IPMN, and MCN lesions and reviews the current level of knowledge and clinical measures.

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