Chromosome numbers, meiotic behavior and pollen fertility in a collection of Paspalum nicorae Parodi accessions

Chromosome number, meiotic behavior and pollen viability were evaluated in a collection of 53 Paspalumnicorae Parodi accessions, which are part of a breeding project of the species. All accessions are tetraploid, with 2n=4x=40.Despite the invariable chromosome numbers, there was variation among accessions in the frequencies of different chromosomeconfigurations at diakinesis and metaphase I, such as univalents, trivalents and quadrivalents. Other abnormalities asbridges and laggards were also observed at anaphase and telophase I. Meiotic indexes ranged from 82.00 to 99.50% andpollen viability from 88.99 to 95.06%. As the species is pseudogamous apomictic, fertile pollen is necessary for endospermformation. Results show that all plants are meiotically stable and have enough fertile pollen to be used as male parents incontrolled crosses

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors

Molecularly defined diffuse leptomeningeal glioneuronal tumor (DLGNT) comprises two subgroups with distinct clinical and genetic features

Diffuse leptomeningeal glioneuronal tumors (DLGNT) represent rare CNS neoplasms which have been included in the 2016 update of the WHO classification. The wide spectrum of histopathological and radiological features can make this enigmatic tumor entity difficult to diagnose. In recent years, large-scale genomic and epigenomic analyses have afforded insight into key genetic alterations occurring in multiple types of brain tumors and provide unbiased, complementary tools to improve diagnostic accuracy. Through genome-wide DNA methylation screening of > 25,000 tumors, we discovered a molecularly distinct class comprising 30 tumors, mostly diagnosed histologically as DLGNTs. Copy-number profiles derived from the methylation arrays revealed unifying characteristics, including loss of chromosomal arm 1p in all cases. Furthermore, this molecular DLGNT class can be subdivided into two subgroups [DLGNT methylation class (MC)-1 and DLGNT methylation class (MC)-2], with all DLGNT-MC-2 additionally displaying a gain of chromosomal arm 1q. Co-deletion of 1p/19q, commonly seen in IDH-mutant oligodendroglioma, was frequently observed in DLGNT, especially in DLGNT-MC-1 cases. Both subgroups also had recurrent genetic alterations leading to an aberrant MAPK/ERK pathway, with KIAA1549:BRAF fusion being the most frequent event. Other alterations included fusions of NTRK1/2/3 and TRIM33:RAF1, adding up to an MAPK/ERK pathway activation identified in 80% of cases. In the DLGNT-MC-1 group, age at diagnosis was significantly lower (median 5 vs 14 years, p < 0.01) and clinical course less aggressive (5-year OS 100, vs 43% in DLGNT-MC-2). Our study proposes an additional molecular layer to the current histopathological classification of DLGNT, of particular use for cases without typical morphological or radiological characteristics, such as diffuse growth and radiologic leptomeningeal dissemination. Recurrent 1p deletion and MAPK/ERK pathway activation represent diagnostic biomarkers and therapeutic targets, respectively—laying the foundation for future clinical trials with, e.g., MEK inhibitors that may improve the clinical outcome of patients with DLGNT

Cytogenetics of Mimosa bimucronata (DC.) O. Kuntze (Mimosoideae, Leguminosae): chromosome number, polysomaty and meiosis

Chromosome numbers (somatic and/or gametic) were determined in 50 populations of M. bimucronata (DC.) O. Kuntze collected in the species area of distribution in Rio Grande do Sul, south Brazil. All populations were diploid (2n = 2x = 26, n = 13). Polysomatic (mostly tetraploid) cells were detected in the seedlings root-tip cells in 39 out of the 41 populations examined, ranging from 3.0 to 28.2 % among populations, but were absent in the root-tips of grown plants. Polysomaty was as well absent in pollen-mother cells. In M. bimucronata pollen-mother cells are joined two-by-two before the onset of meiosis, remaining attached during all the meiotic division until the formation of pollen grain polyads, composed of two sets of four pollen grains each, that are dispersed in this way, which, according to previous suggestions would be an adaptation to ensure high seed set after a single pollination event

Change-Design für Change Agents in universitären Veränderungsprozessen

In recent years, universities are confronted with influential changes - due to i.e. the Bologna Process - and face the challenge to systematically shape the change processes in the field of learning and teaching. The change agent occupies a key role. His task is to accompany and control these changes, which is a sophisticated process and a complex challenge considering occurring conflict situations as well as diverging interests and stakeholder expectations. The epistemological interest of this dissertation is focused on the question how a framework for the design and accompaniment of university-related change processes at the hands of change agents in the field of learning and teaching could look like. The theoretical reflections for the specifics of the organization university, change management as well as for the role of change agents lead to a primary contouring of the components of the framework. In the context of the empirical part, these elements are further differentiated by the use of expert interviews as well as an extensive case study, aiming to focus university-related specifics for change processes in the field of learning and teaching as well to specify the phases of the change process with the use of objectives and interventions. The result of the dissertation is a framework, referenced to as a university change design, which distinguishes between phases, objectives, intervention instruments and interventions in university change processes from the perspective of change agents. The university change design can offer orientation during change processes, to guide the comprehension of the complex challenges of change processes to central fields of action and to reduce uncertainties. Simultaneously, it can be deployed as a basis for reflections.Universitäten sind in den letzten Jahren mit einflussreichen Veränderungen u. a. aufgrund des Bologna-Prozesses konfrontiert und stehen vor der Herausforderung, Veränderungsprozesse im Bereich Studium und Lehre systematisch zu gestalten. Eine Schlüsselfunktion kommt der Rolle des Change Agents zu. Diesem obliegt die Aufgabe, die Veränderung zu begleiten und zu steuern, was einen komplexen Prozess und eine vielschichtige Herausforderung vor dem Hintergrund auftretender Konfliktsituationen sowie divergierender Interessen und Vorstellungen der Stakeholder darstellt. Das Erkenntnisinteresse der vorliegenden Arbeit konzentriert sich auf die Frage, wie ein Bezugssystem zur Gestaltung und Begleitung von universitären Veränderungsprozessen im Bereich Studium und Lehre an Universitäten durch Change Agents aussehen kann. Die theoretischen Reflexionen zu den Spezifika der Organisation Universität, Change Management sowie zur Rolle von Change Agents führen zu einer ersten Konturierung der Komponenten des Bezugssystems. Im Rahmen des empirischen Teils werden die Elemente durch Experteninterviews als Explorationsphase sowie durch eine umfangreiche Fallstudie weiter ausdifferenziert, mit dem Ziel, universitäre Spezifika für Veränderungsprozesse aus dem Bereich Studium und Lehre zu fokussieren sowie die Phasen des Veränderungsprozesses durch Zielsetzungen und Interventionen zu konkretisieren. Das Ergebnis der Arbeit ist ein Bezugssystem, bezeichnet als universitäres Change-Design, welches Phasen, Ziele, Interventionsinstrumentarien und Interventionen in universitären Veränderungsprozessen aus der Perspektive von Change Agents differenziert. Das universitäre Change-Design kann in Veränderungsprozessen Orientierung bieten, um das Verständnis der komplexen Herausforderungen von Veränderungsprozessen auf zentrale Handlungsfelder zu lenken und Unsicherheit zu reduzieren, gleichzeitig als Grundlage für Reflexionen eingesetzt werden

Internet-User mit primärer Hyperhidrose

Die gesundheitsbezogene Lebensqualität, welche einen relevanten Schwerpunkt in der Forschung darstellt, umfasst physische, psychische und soziale Aspekte. Bei Personen mit primärer Hyperhidrose konnten bereits Auswirkungen der Erkrankung auf das subjektive Wohlbefinden festgestellt werden. Die vorliegende Studie beleuchtet unterschiedliche Aspekte der Lebensqualität von Personen mit primärer Hyperhidrose und klärt, inwiefern sich die Stichprobe von der Norm unterscheidet. Zur Anwendung gelangten sowohl generische (SF-36, WHOQOL-100) als auch krankheitsspezifische (HHIQ) Instrumente. Um eine möglichst große Stichprobe zu erlangen, wurde eine Online-Studie mit einer Dauer von sieben Monaten durchgeführt. Die Ergebnisse zeigten eine signifikant niedrigere Lebensqualität bei Personen mit primärer Hyperhidrose als bei der gesunden Normstichprobe. Im Vergleich mit der Norm mit chronischen dermatologischen Erkrankungen konnten ebenfalls signifikante Unterschiede festgestellt werden. Es zeigten sich auch Differenzen bei verschiedenen hyperhidrosespezifischen Charakteristika. Des Weiteren konnten signifikante geschlechtsspezifische Unterschiede hinsichtlich der Lebensqualität festgestellt werden. Demnach scheinen Frauen mit primärer Hyperhidrose in gewissen Bereichen weniger beeinträchtigt zu sein als Männer.Health-related quality of life, which comprises physical, social and psychological aspects, is an important research area. Patients, who suffer from primary hyperhidrosis, are limited in their subjective well-being. The present study explores the different aspects of quality of life of people with primary hyperhidrosis and compares their well-being with different norms. For the process of information gathering served generic instruments (SF-36, WHOQOL-100) and parts of disease-specific questionnaires (HHIQ). An online-survey provided the means to acquire a huge sample of participants. The results showed significant reductions of health-related quality of life of patients with primary hyperhidrosis compared with the healthy norm sample and differences in subjective well-being between the sample with chronic skin diseases and study participants. The present study also discovered several differences in various disease-specific characteristics. Furthermore, differences between sexes concerning health-related quality of life could be found. Men tend to suffer more from primary hyperhidrosis than women