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51.
The expansion of Dermacentor reticulatus to new geographical areas has been observed in several countries in Europe, including Poland and it’s neighbors. In 2011 and 2012, a total of 148 host-seeking D. reticulatus ticks were collected after flagging the vegetation in Lower Silesia, south-western Poland. Tick monitoring was conducted in mixed and deciduous forest, on meadows, in river valleys and ecotones between forested and grassy areas. The ornate dog ticks were found in 10 out of 33 sites located in five districts: Legnica, Wroclaw, ?roda ?l?ska, Lubin and Boleslawiec County. All sites where D. reticulatus ticks were found are located to the south-west of the Odra River. The greatest distance between these disconnected localities was approximately 90 km. It seems that at present the southern boundary of the range is Wroclaw district. This study indicates that D. reticulatus can be ranked as a typical element of the fauna in Lower Silesia in southwestern Poland.  相似文献   
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During summer 2007, Arctic microphytobenthic potential primary production was measured at several stations around the coastline of Kongsfjorden (Svalbard, Norway) at ≤5 m water depth and at two stations at five different water depths (5, 10, 15, 20, 30 m). Oxygen planar optode sensor spots were used ex situ to determine oxygen exchange in the overlying water of intact sediment cores under controlled light (ca. 100 μmol photons m−2 s−1) and temperature (2–4°C) conditions. Patches of microalgae (mainly diatoms) covering sandy sediments at water depths down to 30 m showed high biomass of up to 317 mg chl a m−2. In spite of increasing water depth, no significant trend in “photoautotrophic active biomass” (chl a, ratio living/dead cells, cell sizes) and, thus, in primary production was measured at both stations. All sites from ≤5 to 30 m water depth exhibited variable rates of net production from −19 to +40 mg O2 m−2 h−1 (−168 to +360 mg C m−2 day−1) and gross production of about 2–62 mg O2 m−2 h−1 (17–554 mg C m−2 day−1), which is comparable to other polar as well as temperate regions. No relation between photoautotrophic biomass and gross/net production values was found. Microphytobenthos demonstrated significant rates of primary production that is comparable to pelagic production of Kongsfjorden and, hence, emphasised the importance as C source for the zoobenthos.  相似文献   
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For safe biosolid-land-applying, sludge should be contaminant-free. However, it may contain important amounts of micropollutants, not removed in the wastewater-treatment-processes. An alternative treatment with the fungus Trametes versicolor was applied in sterile solid-phase systems consisting of sludge and a lignocellulosic substrate. Fungal colonization and activity were demonstrated during the process, according to monitoring of ergosterol, laccase activity and the naproxen-degradation test (ND24). Fourteen out of 43 analyzed pharmaceuticals were found in the raw sludge. After treatment, phenazone, bezafibrate, fenofibrate, cimetidine, clarithromycin, sulfamethazine and atenolol were completely removed, while removals between 42% and 80% were obtained for the remaining pharmaceuticals. Toxicological analyses (Daphnia magna, Vibrio fischeri and seed germination) showed an important reduction in sludge toxicity after treatment. Results suggest that a solid-phase treatment with T. versicolor may reduce the ecotoxicological impact of micropollutants present in sewage sludge. This is the first report of a fungal-approach for elimination of emerging pollutants from biosolids.  相似文献   
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Background

rs6943555 in AUTS2 has been shown to modulate ethanol consumption. We hypothesized that rs6943555 might be associated with completed suicide.

Methods

We genotyped rs6943555 in 625 completed suicides and 3861 controls using real-time TaqMan Allelic Discrimination Assay. All individuals were Polish Caucasians.

Results

We detected an association between suicide and rs6943555 A allele (OR = 1.17, P = 0.018 for allelic comparison, OR = 1.24, P = 0.013 for dominant, and OR = 1.18, P = 0.020 for co-dominant model of inheritance). The association remained significant after adjusting for age and gender (co-dominant: P = 0.002 and dominant model: P = 0.001). After stratifying suicides according to blood ethanol concentration (BAC≤ 20 mg/dl and BAC > 20 mg/dl) the association remained significant only for cases who committed suicide under influence of alcohol (co-dominant: OR  =  1.37, P = 0.004 and dominant model: OR = 1.45, P = 0.006). To validate this finding we genotyped another cohort of 132 cases. We reproduced the association between rs6943555 A allele and suicide under influence of ethanol (allelic comparison: OR = 1.55, P = 0.023; co-dominant : OR = 1.54, P = 0.031; dominant model: OR = 1.84, P = 0.015). Analyzing pooled suicides with BAC >20 mg/dl (N = 300) we found the association of rs6943555 A allele not only vs. controls (allelic OR = 1.41, P = 0.00029) but also vs. cases with BAC ≤ 20 mg/dl (N = 449, allelic OR = 1.33, P = 0.019).

Conclusions

In our study rs6943555 A allele is associated with suicide committed after drinking ethanol shortly before death. The rs6943555 A allele may be linked to adverse emotional reaction to ethanol, which could explain the association with lower consumption in general population as well as the predisposition to suicide under influence of ethanol.  相似文献   
58.
Crystals of pyruvate phosphate dikinase in complex with a substrate analogue inhibitor, phosphonopyruvate (K(i) = 3 microM), have been obtained in the presence of Mg(2+). The structure has been determined and refined at 2.2 A resolution, revealing that the Mg(2+)-bound phosphonopyruvate binds in the alpha/beta-barrel's central channel, at the C-termini of the beta-strands. The mode of binding resembles closely the previously proposed PEP substrate binding mode, inferred by the homology of the structure (but not sequence homology) to pyruvate kinase. Kinetic analysis of site-directed mutants, probing residues involved in inhibitor binding, showed that all mutations resulted in inactivation, confirming the key role that these residues play in catalysis. Comparison between the structure of the PPDK-phosphonopyruvate complex and the structures of two complexes of pyruvate kinase, one with Mg(2+)-bound phospholactate and the other with Mg(2+)-oxalate and ATP, revealed that the two enzymes share some key features that facilitate common modes of substrate binding. There are also important structural differences; most notably, the machinery for acid/base catalysis is different.  相似文献   
59.
Elaborate sexually selected ornaments and armaments are costly but increase the reproductive success of their bearers (usually males). It has been postulated that high-quality males can invest disproportionately more in such traits, making those traits honest signals of genetic quality. However, genes associated with such traits may have sexually antagonistic effects on fitness. Here, using a bulb mite Rhizoglyphus robini, a species in which a distinct dimorphism exists between males in the expression of a sexually selected weapon, we compare inbreeding and gender load between lines derived from armed fighters and unarmed scramblers. After four generations of sib-mating, inbreeding depression for female fitness was significantly lower in fighter-derived lines compared to scrambler-derived lines, suggesting that fighter males had significantly higher genetic quality. However, outbred females from fighter-derived lines had significantly lower fitness compared to outbred females from scrambler-derived lines, demonstrating significant gender load associated with the presence of a sexually selected male weapon. Our results imply that under outbreeding, genetic benefits of mating with bearers of elaborate sexually selected traits might be swamped by the costs of decreased fitness of female progeny due to sexually antagonistic effects.  相似文献   
60.
Mesenchymal stem cells (MSCs) are a multipotent cell population which has been described to exert renoprotective and regenerative effects in experimental models of kidney injury. Several lines of evidence indicate that MSCs also have the ability to contribute to nephrogenesis, suggesting that the cells can be employed in stem cell-based applications aimed at de novo renal tissue generation. In this study we re-evaluate the capacity of mouse and human bone marrow-derived MSCs to contribute to the development of renal tissue using a novel method of embryonic kidney culture. Although MSCs show expression of some genes involved in renal development, their contribution to nephrogenesis is very limited in comparison to other stem cell types tested. Furthermore, we found that both mouse and human MSCs have a detrimental effect on the ex vivo development of mouse embryonic kidney, this effect being mediated through a paracrine action. Stimulation with conditioned medium from a mouse renal progenitor population increases the ability of mouse MSCs to integrate into developing renal tissue and prevents the negative effects on kidney development, but does not appear to enhance their ability to undergo nephrogenesis.  相似文献   
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