9,796 research outputs found
A new species of Ribautiella (Myriapoda, Symphyla, Scolopendrellidae) from an Amazonian black-water inundation forest and notes on its natural history and ecology
Ribautiella amazonica is described from a black-water inundation forest near Manaus, Brazil. The genus is recorded for the first time for the Americas. R. amazonica was predominantly collected from the forest soil, mainly between 7 and 14 cm depth and is considered euedaphic. Data indicate, that advanced immature stages and adults withstand forest-inundation of 5 - 6 months duration in the soil and reproduce in the early part of the emersion period
Optimal Investment Strategies and Performance Sharing Rules for Pension Schemes with Minimum Guarantee
There is a potential conflict of interest between a pension fund sponsor and future pensioners when they share unequally in the pension fund performance. Thus, when a scheme offers a yearly guaranteed minimum return to pensioners, as is presently the case with German Pensionskassen, the sponsors cannot afford to invest in risky assets and consequently, pensioners end up with safe but very low expected returns. We examine optimal investment strategies for sponsors under alternative performance sharing rules and seek the rules that are most beneficial to pensioners. We find that the current yearly performance sharing rule imposed on Pensionskassen could be tilted in favor of sponsors without impairing the welfare of pensioners. We also find that the welfare of pensioners would be greatly enhanced if the guaranteed minimum return were applied to the cumulative return since inception of the scheme rather than to yearly returns. The ensuing credit risk taken by pensioners on sponsors could be kept to a minimum by proper regulation; this would induce sponsors to adopt safe constant proportionality portfolio insurance (CPPI) style investment strategies.Private pension schemes, benefit-sharing rules, capital guaranteed products, constant mix strategies, constant proportionality portfolio insurance strategies, utility theory
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Engineering of Bioenergy Crops: Dominant Genetic Approaches to Improve Polysaccharide Properties and Composition in Biomass.
Large-scale, sustainable production of lignocellulosic bioenergy from biomass will depend on a variety of dedicated bioenergy crops. Despite their great genetic diversity, prospective bioenergy crops share many similarities in the polysaccharide composition of their cell walls, and the changes needed to optimize them for conversion are largely universal. Therefore, biomass modification strategies that do not depend on genetic background or require mutant varieties are extremely valuable. Due to their preferential fermentation and conversion by microorganisms downstream, the ideal bioenergy crop should contain a high proportion of C6-sugars in polysaccharides like cellulose, callose, galactan, and mixed-linkage glucans. In addition, the biomass should be reduced in inhibitors of fermentation like pentoses and acetate. Finally, the overall complexity of the plant cell wall should be modified to reduce its recalcitrance to enzymatic deconstruction in ways that do no compromise plant health or come at a yield penalty. This review will focus on progress in the use of a variety of genetically dominant strategies to reach these ideals. Due to the breadth and volume of research in the field of lignin bioengineering, this review will instead focus on approaches to improve polysaccharide component plant biomass. Carbohydrate content can be dramatically increased by transgenic overexpression of enzymes involved in cell wall polysaccharide biosynthesis. Additionally, the recalcitrance of the cell wall can be reduced via the overexpression of native or non-native carbohydrate active enzymes like glycosyl hydrolases or carbohydrate esterases. Some research in this area has focused on engineering plants that accumulate cell wall-degrading enzymes that are sequestered to organelles or only active at very high temperatures. The rationale being that, in order to avoid potential negative effects of cell wall modification during plant growth, the enzymes could be activated post-harvest, and post-maturation of the cell wall. A potentially significant limitation of this approach is that at harvest, the cell wall is heavily lignified, making the substrates for these enzymes inaccessible and their activity ineffective. Therefore, this review will only include research employing enzymes that are at least partially active under the ambient conditions of plant growth and cell wall development
Reporting guidelines, review of methodological standards, and challenges toward harmonization in bone marrow adiposity research. Report of the Methodologies Working Group of the International Bone Marrow Adiposity Society
The interest in bone marrow adiposity (BMA) has increased over the last decade due to its association with, and potential role, in a range of diseases (osteoporosis, diabetes, anorexia, cancer) as well as treatments (corticosteroid, radiation, chemotherapy, thiazolidinediones). However, to advance the field of BMA research, standardization of methods is desirable to increase comparability of study outcomes and foster collaboration. Therefore, at the 2017 annual BMA meeting, the International Bone Marrow Adiposity Society (BMAS) founded a working group to evaluate methodologies in BMA research. All BMAS members could volunteer to participate. The working group members, who are all active preclinical or clinical BMA researchers, searched the literature for articles investigating BMA and discussed the results during personal and telephone conferences. According to the consensus opinion, both based on the review of the literature and on expert opinion, we describe existing methodologies and discuss the challenges and future directions for (1) histomorphometry of bone marrow adipocytes, (2
Transoral, retromolar, para-tonsillar approach to the styloid process in 6 patients with Eagle's syndrome
Objectives: Eagle's syndrome is caused by an elongated or mineralised styloid process and characterised by facial
and pharyngeal pain, odynophagia and dysphagia. Diagnosis is based on clinical findings. However radiologic
imaging, like panoramic radiograph, helps to confirm the diagnosis.
There are different treatments of the Eagle's syndrome. Anti-inflammatory medication (carbamazepime, corticosteroids)
and/or surgical interventions are established. The aim of the different surgical techniques is to resect the
elongated styloid process near the skull base.
Study Design: A transoral, retromolar, para-tonsillar approach was performed to expose and resect the elongated
calcified styloid process in a consecutive series of six patients. The use of different angled ring curettes, generally
used in hypophysis surgery, facilitated the preparation of the styloid process through the surrounding tissue to the
skull base, without a compromise to the surrounding tissue.
Clinical examinations were performed pre- and postoperatively (3 month and after 1 year after surgery) in all
patients.
Results: No intra- or postoperative complications were observed. The hypophysis ring curettes facilitated the
preparation of the styloid process to the skull base.
Conclusions: The transoral, retromolar, para-tonsillar approach is a secure and fast method to resect an elongated
symptomatic styloid process. Side effects of the classical transoral trans-tonsillar approach did not occur
"Trödler des Unbegreiflichen" : die Schriftsteller und ihr Streit im deutschsprachigen Exil
Das Exil war sein Schicksal. Davon ist er zeit seines Lebens nicht losgekommen. Hans Sahl, aus Dresden gebürtig, gehörte zu jenen brillanten Intellektuellen, die bereits im geistigen Leben der Weimarer Republik eine Rolle spielten, vor den Nazis fliehen mußten und als ungeliebte Heimkehrer in der Bundesrepublik lange vergessen blieben. Erst in seinen letzten Lebensjahren, die der fast erblindete Autor in Tübingen verbrachte, wurde er mit Preisen überschüttet, wurden seine Gedichte und Romane neuaufgelegt. “Wir sind die Letzten“, hieß eine Gedichtsammlung, die 1941 erschien, in der sich dieser „Trödler des Unbegreiflichen“, wie er sich nannte, als Moralist und Wahrheitsfanatiker von hohen Graden zu erkennen gab
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