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71.
Wilfried Hasselbach 《Zoology in the Middle East.》2013,59(1):139-140
Summary In this publication, a subdivision of the genus Annenica O. Boettger, 1877 sensu Auct. is proposed. One result of our study is the recognition of the genus Sprattia O. Boettger, 1883 for most of the South Anatolian species of the former genus Armenica. The genus Astrogena Szekeres, 1970, which was synonymised by H. NORDSIECK (1975: 98) with Armenica is redefined and used as a subgenus of Armenica for some species. Extensive recent collections contain new species and subspecies of this genus, which are described here. 相似文献
72.
AbstractAn evaluation of nitrite determination in marine lake sediments has shown that spectrophotometric measurements can be in error due to light scattering by colloidal (<0.2 μm) matter in extract solutions and incomplete nitrite recovery. The scatter error can be minimised by using uncoloured extract in the reference beam but precision at low levels remains poor (RSD 25 to 100%). Recovery tests on ‘spiked’ sediment indicated that optimum retrieval (~85%) occurred with 30 minute mixing with 0.2 M NH4Cl, using a sediment to extractant ratio of 1:30. To counter this variable, calibration based on standard addition to sample suspensions is recommended. Modified procedure proposed is suitable for measuring up to 10 μg g?1 of nitrite N; the lake sediments tested contained <100 ng g?1 相似文献
73.
Jennifer G. Howeth Jerome J. Weis Jakob Brodersen Elizabeth C. Hatton David M. Post 《Ecology and evolution》2013,3(15):5031-5044
Contemporary insights from evolutionary ecology suggest that population divergence in ecologically important traits within predators can generate diversifying ecological selection on local community structure. Many studies acknowledging these effects of intraspecific variation assume that local populations are situated in communities that are unconnected to similar communities within a shared region. Recent work from metacommunity ecology suggests that species dispersal among communities can also influence species diversity and composition but can depend upon the relative importance of the local environment. Here, we study the relative effects of intraspecific phenotypic variation in a fish predator and spatial processes related to plankton species dispersal on multitrophic lake plankton metacommunity structure. Intraspecific diversification in foraging traits and residence time of the planktivorous fish alewife (Alosa pseudoharengus) among coastal lakes yields lake metacommunities supporting three lake types which differ in the phenotype and incidence of alewife: lakes with anadromous, landlocked, or no alewives. In coastal lakes, plankton community composition was attributed to dispersal versus local environmental predictors, including intraspecific variation in alewives. Local and beta diversity of zooplankton and phytoplankton was additionally measured in response to intraspecific variation in alewives. Zooplankton communities were structured by species sorting, with a strong influence of intraspecific variation in A. pseudoharengus. Intraspecific variation altered zooplankton species richness and beta diversity, where lake communities with landlocked alewives exhibited intermediate richness between lakes with anadromous alewives and without alewives, and greater community similarity. Phytoplankton diversity, in contrast, was highest in lakes with landlocked alewives. The results indicate that plankton dispersal in the region supplied a migrant pool that was strongly structured by intraspecific variation in alewives. This is one of the first studies to demonstrate that intraspecific phenotypic variation in a predator can maintain contrasting patterns of multitrophic diversity in metacommunities. 相似文献
74.
Joanna Szkandera Gudrun Absenger Bernadette Liegl-Atzwanger Martin Pichler Michael Stotz Stefan Gerger Maximilian Zacherl Wilfried Renner Miao Haijun Andreas Leithner Armin Gerger 《Cancer epidemiology》2013,37(6):1003-1009
BackgroundDNA repair mechanisms play a major role in cancer risk and progression. Germline variants in DNA repair genes may result in altered gene function and/or activity, thereby causing inter-individual differences in a patient's tumor recurrence capacity. In genes of the DNA repair pathway the gene variants RAD51 rs1801320 G > C, XRCC2 rs3218536 G > A and XPD rs13181 A > C have been previously related to genetic predisposition and prognosis of various cancer entities. In this study we investigated the association between these polymorphisms and time to recurrence (TTR) and overall survival (OS) in soft-tissue sarcoma (STS) patients after curative surgery.MethodsTwo hundred sixty STS patients were included in this retrospective study. Germline DNA was genotyped by 5′-exonuclease (TaqMan) technology. Kaplan Meier curves and multivariate Cox proportional models were calculated for TTR and OS.ResultsA statistically significant association was observed between tumor grade and adjuvant radiotherapy and TTR and between tumor grade and OS. No association was found between RAD51 rs1801320 G > C, XRCC2 rs3218536 G > A and XPD rs13181 A > C and TTR and OS in univariate and multivariate analysis.ConclusionOur results underline a prognostic effect of tumor grade and adjuvant radiotherapy in STS patients but indicate no association between RAD51 rs1801320 G > C, XRCC2 rs3218536 G > A and XPD rs13181 A > C and clinical outcome in STS patients after curative surgery. 相似文献
75.
Jonas De Vylder Jan Aelterman Trees Lepez Mado Vandewoestyne Koen Douterloigne Dieter Deforce Wilfried Philips 《PloS one》2013,8(1)
Cell nuclei detection in fluorescent microscopic images is an important and time consuming task in a wide range of biological applications. Blur, clutter, bleed through and partial occlusion of nuclei make individual nuclei detection a challenging task for automated image analysis. This paper proposes a novel and robust detection method based on the active contour framework. Improvement over conventional approaches is achieved by exploiting prior knowledge of the nucleus shape in order to better detect individual nuclei. This prior knowledge is defined using a dictionary based approach which can be formulated as the optimization of a convex energy function. The proposed method shows accurate detection results for dense clusters of nuclei, for example, an F-measure (a measure for detection accuracy) of 0.96 for the detection of cell nuclei in peripheral blood mononuclear cells, compared to an F-measure of 0.90 achieved by state-of-the-art nuclei detection methods. 相似文献
76.
Afitap Derya K?prülü Renate Kastner Sebastian Wienerroither Caroline Lassnig Eva Maria Putz Olivia Majer Benjamin Reutterer Veronika Sexl Karl Kuchler Mathias Müller Thomas Decker Wilfried Ellmeier 《PloS one》2013,8(3)
In this study we investigated the role of Bruton''s tyrosine kinase (Btk) in the immune response to the Gram-positive intracellular bacterium Listeria monocytogenes (Lm). In response to Lm infection, Btk was activated in bone marrow-derived macrophages (BMMs) and Btk
−/− BMMs showed enhanced TNF-α, IL-6 and IL-12p40 secretion, while type I interferons were produced at levels similar to wild-type (wt) BMMs. Although Btk-deficient BMMs displayed reduced phagocytosis of E. coli fragments, there was no difference between wt and Btk
−/− BMMs in the uptake of Lm upon infection. Moreover, there was no difference in the response to heat-killed Lm between wt and Btk
−/− BMMs, suggesting a role for Btk in signaling pathways that are induced by intracellular Lm. Finally, Btk
−/− mice displayed enhanced resistance and an increased mean survival time upon Lm infection in comparison to wt mice. This correlated with elevated IFN-γ and IL-12p70 serum levels in Btk
−/− mice at day 1 after infection. Taken together, our data suggest an important regulatory role for Btk in macrophages during Lm infection. 相似文献
77.
Andreas Schmideder Xenia Priebe Mark Rubenbauer Thomas Hoffmann Fong-Chin Huang Wilfried Schwab Dirk Weuster-Botz 《Bioprocess and biosystems engineering》2016,39(9):1409-1414
Whole cells of Escherichia coli overexpressing a glucosyltransferase from Vitis vinifera were used for the glucosylation of geraniol to geranyl glucoside. A high cell density cultivation process for the production of whole-cell biocatalysts was developed, gaining a dry cell mass concentration of up to 67.6 ± 1.2 g L?1 and a glucosyltransferase concentration of up to 2.7 ± 0.1 g protein L?1 within a process time of 48 h. Whole-cell batch biotransformations in milliliter-scale stirred-tank bioreactors showed highest conversion of geraniol at pH 7.0 although the pH optimum of the purified glucosyltransferase was at pH 8.5. The biocatalytic batch process performance was improved significantly by the addition of a water-immiscible ionic liquid (N-hexylpyridinium bis(trifluoromethylsulfonyl)imid) for in situ substrate supply. The so far highest final geranyl glucoside concentration (291 ± 9 mg L?1) and conversion (71 ± 2 %) reported for whole-cell biotransformations of geraniol were achieved with 5 % (v/v) of the ionic liquid. 相似文献
78.
Background
Achilles tendon injuries are known to commonly occur in runners. During running repeated impacts are transferred in axial direction along the lower leg, therefore possibly affecting the oscillation behavior of the Achilles tendon. The purpose of the present study was to explore the effects of different footwear modifications and different ground conditions (over ground versus treadmill) on oscillations at the Achilles tendon.Methods
Oscillations were measured in 20 male runners using two tri-axial accelerometers. Participants ran in three different shoe types on a treadmill and over ground. Data analysis was limited to stance phase and performed in time and frequency space. Statistical comparison was conducted between oscillations in vertical and horizontal direction, between running shoes and between ground conditions (treadmill versus over ground running).Results
Differences in the oscillation behavior could be detected between measurement directions with peak accelerations in the vertical being lower than those in the horizontal direction, p < 0.01. Peak accelerations occurred earlier at the distal accelerometer than at the proximal one, p < 0.01. Average normalized power differed between running shoes (p < 0.01) with harder damping material resulting in higher power values. Little to no power attenuation was found between the two accelerometers. Oscillation behavior of the Achilles tendon is not influenced by ground condition.Conclusion
Differences in shoe configurations may lead to variations in running technique and impact forces and therefore result in alterations of the vibration behavior at the Achilles tendon. The absence of power attenuation may have been caused by either a short distance between the two accelerometers or high stiffness of the tendon. High stiffness of the tendon will lead to complete transmission of the signal along the Achilles tendon and therefore no attenuation occurs. 相似文献79.
80.
Serge Michalet Guillaume Minard Wilfried Chevalier Guillaume Meiffren Yoann Saucereau Van Tran Van Gilles Comte Florence-Hélène Tran Claire Valiente Moro 《Environmental microbiology》2019,21(12):4662-4674
Aedes albopictus is a vector of arboviruses and filarial nematodes. Originating from Asia, this mosquito has rapidly expanded its geographical distribution and colonized areas across both temperate and tropical regions. Due to the increase in insecticide resistance, the use of environmentally friendly vector control methods is encouraged worldwide. Using methods based on semiochemicals in baited traps are promising for management of mosquito populations. Interestingly, human skin microbiota was shown to generate volatile compounds that attract the mosquito species Anopheles gambiae and Aedes aegypti. Here, we investigated the composition of skin bacteria from different volunteers and the attractive potential of individual isolates to nulliparous Ae. albopictus females. We showed that three out of 16 tested isolates were more attractive and two were more repulsive. We identified dodecenol as being preferentially produced by attractive isolates and 2-methyl-1-butanol (and to a lesser extent 3-methyl-1-butanol) as being overproduced by these isolates compared with the other ones. Those bacterial volatile organic compounds represent promising candidates but further studies are needed to evaluate their potential application for baited traps improvement. 相似文献