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121.
By A. T. Silva J. M. Santos A. C. Franco M. T. Ferreira A. N. Pinheiro 《Zeitschrift fur angewandte Ichthyologie》2009,25(2):173-177
Trends in fish passage studies are increasingly moving towards a holistic approach in considering the movements of a wide range of fish species and other aquatic fauna. In this context, it is important to consider not only salmonids and other game species, but also coarse species such as cyprinids. Moreover, knowledge of their behaviour when confronted with fishways is limited, particularly their upstream movements with regard to different hydraulic configurations. To address this deficit, research was conducted in an indoor full-scale pool-type fishway to assess the cyprinid Iberian barbel Barbus bocagei (Steindachner, 1864) response to the simultaneous presence of submerged orifices and surface notches with adjustable dimensions in association with two different flow regimes over the notches, i.e. plunging and streaming. Overall, orifices (76%) were the clear choice to negotiate the fishway. When the flow was in the plunging mode, a significantly higher proportion of fish selected the orifices to move upstream, but the proportions were equal during the streaming mode. The time taken to enter the fishway differed significantly according to the chosen discharge device and was lower for submerged orifices (52 s to 35 min.). The present study identified key factors in Iberian barbel upstream movements, which provide direct applications to future fishway designs for this species. 相似文献
122.
By A. S. Tarkan M. Özulu Ö. Gaygusuz Ç. G. Gaygusuz G. Saç 《Zeitschrift fur angewandte Ichthyologie》2009,25(2):230-231
Length–weight relationships are given on six freshwater fish species ( Phoxinus phoxinus , Cobitis vardarensis , Neogobius gymnotrachelus , Proterorhinus marmoratus, Petroleuciscus borysthenicus and Gambusia holbrooki ) from four streams flowing into Lake Sapanca, north-western Turkey. 相似文献
123.
Length–weight relationships of 17 less-studied fish species from Çanakkale, Marmara region of Turkey
By O. Ozen H. Ayyildiz A. Oztekin A. Altin 《Zeitschrift fur angewandte Ichthyologie》2009,25(2):238-239
This study reports length–weight relationships for 17 cryptic and rare species, Aidablennius sphynx , Arnoglossus kessleri , Callionymus pusillus , Callionymus risso , Clinitrachus argentatus , Echiichthys vipera , Gobius geniporus , Gobius paganellus , Labrus viridis , Lepadogaster lepadogaster , Ophidion barbatum , Pomatoschistus minutus , Pomatoschistus pictus , Salaria pavo , Tripterygion delaisi , Tripterygion tripteronotus and Zebrus zebrus from Çanakkale near shores in the Marmara region of Turkey. 相似文献
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125.
Bruna Aparecida Souza Machado Gabriele de Abreu Barreto Aline Silva Costa Samantha Serra Costa Rejane Pina Dantas Silva Danielle Figuerêdo da Silva Hugo Neves Brand?o José Luiz Carneiro da Rocha Silmar Baptista Nunes Marcelo Andres Umsza-Guez Francine Ferreira Padilha 《PloS one》2015,10(8)
The aim of this study was to determine the best processing conditions to extract Brazilian green propolis using a supercritical extraction technology. For this purpose, the influence of different parameters was evaluated such as S/F (solvent mass in relation to solute mass), percentage of co-solvent (1 and 2% ethanol), temperature (40 and 50°C) and pressure (250, 350 and 400 bar) using supercritical carbon dioxide. The Global Yield Isotherms (GYIs) were obtained through the evaluation of the yield, and the chemical composition of the extracts was also obtained in relation to the total phenolic compounds, flavonoids, antioxidant activity and 3,5-diprenyl-4-hydroxicinnamic acid (Artepillin C) and acid 4-hydroxycinnamic (p-coumaric acid). The best results were identified at 50°C, 350 bar, 1% ethanol (co-solvent) and S/F of 110. These conditions, a content of 8.93±0.01 and 0.40±0.05 g/100 g of Artepillin C and p-coumaric acid, respectively, were identified indicating the efficiency of the extraction process. Despite of low yield of the process, the extracts obtained had high contents of relevant compounds, proving the viability of the process to obtain green propolis extracts with important biological applications due to the extracts composition. 相似文献
126.
CYP2J2 overexpression ameliorates hyperlipidemia via increased fatty acid oxidation mediated by the AMPK pathway
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127.
Peng Liu Jennifer B. Paulson Colleen L. Forster Samantha L. Shapiro Karen H. Ashe Kathleen R. Zahs 《PloS one》2015,10(5)
Amyloid plaques composed of β-amyloid (Aβ) protein are a pathological hallmark of Alzheimer’s disease. We here report the generation and characterization of a novel transgenic mouse model of Aβ toxicity. The rTg9191 mice harbor a transgene encoding the 695 amino-acid isoform of human amyloid precursor protein (APP) with the Swedish and London mutations (APPNLI) linked to familial Alzheimer’s disease, under the control of a tetracycline-response element, as well as a transgene encoding the tetracycline transactivator, under the control of the promoter for calcium-calmodulin kinase IIα. In these mice, APPNLI is expressed at a level four-fold that of endogenous mouse APP and its expression is restricted to forebrain regions. Transgene expression was suppressed by 87% after two months of doxycycline administration. Histologically, we showed that (1) Aβ plaques emerged in cerebral cortex and hippocampus as early as 8 and 10.5-12.5 months of age, respectively; (2) plaque deposition progressed in an age-dependent manner, occupying up to 19% of cortex at ~25 months of age; and (3) neuropathology—such as abnormal neuronal architecture, tau hyperphosphorylation and misfolding, and neuroinflammation—was observed in the vicinity of neuritic plaques. Biochemically, we determined total Aβ production at varied ages of mice, and we showed that mice produced primarily fibrillar Aβ assemblies recognized by conformation-selective OC antibodies, but few non-fibrillar oligomers (e.g., Aβ*56) detectable by A11 antibodies. Finally, we showed that expression of the tetracycline transactivator resulted in reduced brain weight and smaller dentate-gyrus size. Collectively, these data indicate that rTg9191 mice may serve as a model for studying the neurological effects of the fibrillar Aβ assemblies in situ. 相似文献
128.
Mechanisms enabling men to identify women likely to engage in extra-pair copulations (EPCs) would be advantageous in avoiding cuckoldry. Men’s judgments of female sexual faithfulness often show high consensus, but accuracy appears poor. We examined whether accuracy of these judgments made to images of women could be improved through i) employing a forced choice task, in which men were asked to select the more faithful of two women and/or ii) providing men with full person images. In Experiment 1, men rated 34 women, for whom we had self-reported EPC behavior, on faithfulness, trustworthiness or attractiveness from either face or full person photographs. They then completed a forced choice task, selecting the more faithful of two woman from 17 pairs of images, each containing one woman who had reported no EPCs and one who had reported two or more EPCs. Men were unable to rate faithfulness with any accuracy, replicating previous findings. However, when asked to choose the more faithful of two women, they performed significantly above chance, although the ability to judge faithfulness at above-chance levels did not generalize to all pairs of women. Although there was no significant difference in accuracy for face and full person image pairs, only judgments from faces were significantly above chance. In Experiment 2, we showed that this accuracy for faces was repeatable in a new sample of men. We also showed that individual variation in accuracy was unrelated to variation in preferences for faithfulness in a long-term partner. Overall, these results show that men’s judgments of faithfulness made from faces of unfamiliar women may contain a kernel of truth. 相似文献
129.
Timothy D. Rohrbach Nishi Shah William P. Jackson Erin V. Feeney Samantha Scanlon Robert Gish Ryan Khodadadi Stephen O. Hyde Patricia H. Hicks Joshua C. Anderson John S. Jarboe Christopher D. Willey 《PloS one》2015,10(10)
Translocation to the nucleus of diacylglycerol kinase (DGK)– ζ is dependent on a sequence homologous to the effector domain of Myristoylated Alanine Rich C-Kinase Substrate (MARCKS). These data would suggest that MARCKS could also localize to the nucleus. A single report demonstrated immunofluorescence staining of MARCKS in the nucleus; however, further experimental evidence confirming the specific domain responsible for this localization has not been reported. Here, we report that MARCKS is present in the nucleus in GBM cell lines. We then over-expressed wild-type MARCKS (WT) and MARCKS with the effector domain deleted (ΔED), both tagged with V5-epitope in a GBM cell line with low endogenous MARCKS expression (U87). We found that MARCKS-WT localized to the nucleus, while the MARCKS construct without the effector domain remained in the cytoplasm. We also found that over-expression of MARCKS-WT resulted in a significant increase in total cellular phosphatidyl-inositol (4,5) bisphosphate (PIP2) levels, consistent with prior evidence that MARCKS can regulate PIP2 levels. We also found increased staining for PIP2 in the nucleus with MARCKS-WT over-expression compared to MARCKS ΔED by immunofluorescence. Interestingly, we observed MARCKS and PIP2 co-localization in the nucleus. Lastly, we found changes in gene expression when MARCKS was not present in the nucleus (MARCKS ΔED). These data indicate that the MARCKS effector domain can function as a nuclear localization signal and that this sequence is critical for the ability of MARCKS to regulate PIP2 levels, nuclear localization, and gene expression. These data suggests a novel role for MARCKS in regulating nuclear functions such as gene expression. 相似文献
130.
Olga Perovic Samantha Iyaloo Ranmini Kularatne Warren Lowman Noma Bosman Jeannette Wadula Sharona Seetharam Adriano Duse Nontombi Mbelle Colleen Bamford Halima Dawood Yesholata Mahabeer Prathna Bhola Shareef Abrahams Ashika Singh-Moodley 《PloS one》2015,10(12)