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Three sampling methods for estimating abundance and size of blue cod Parapercis colias were compared inside and outside Kapiti Marine Reserve, New Zealand (40° 49′ 31·77′′ S; 174° 55′ 02·87′′ E). Two baited methods, baited underwater video (BUV) and experimental angling (EA), were more efficient and had lower levels of estimate variation than diver‐based underwater visual census (UVC). The BUV and EA recorded more fish and of greater size ranges than UVC, and also had fewer zero count replicates. The BUV and EA methodologies revealed highly significant differences in abundance and size of fish between sites (reserve v. non‐reserve), whereas UVC revealed no such differences. These results indicate that BUV is likely to be the most accurate, cost‐effective and easy to use methodology for the surveying of carnivorous temperate reef fishes for future monitoring. It is noted, however, that new data acquired using the BUV methodology may need to be compared over a calibration period to data acquired using the UVC methodology to ensure that historical data sets derived from UVC still have validity and application for future monitoring activity. 相似文献
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Scott G. Shanks Lindsay N. Carpp Marion S. Struthers Rebecca K. McCann Nia J. Bryant 《PloS one》2012,7(11)
Intracellular membrane trafficking pathways must be tightly regulated to ensure proper functioning of all eukaryotic cells. Central to membrane trafficking is the formation of specific SNARE (soluble N-ethylmeleimide-sensitive factor attachment protein receptor) complexes between proteins on opposing lipid bilayers. The Sec1/Munc18 (SM) family of proteins play an essential role in SNARE-mediated membrane fusion, and like the SNAREs are conserved through evolution from yeast to humans. The SM protein Vps45 is required for the formation of yeast endosomal SNARE complexes and is thus essential for traffic through the endosomal system. Here we report that, in addition to its role in regulating SNARE complex assembly, Vps45 regulates cellular levels of its SNARE binding partners: the syntaxin Tlg2 and the v-SNARE Snc2: Cells lacking Vps45 have reduced cellular levels of Tlg2 and Snc2; and elevation of Vps45 levels results in concomitant increases in the levels of both Tlg2 and Snc2. As well as regulating traffic through the endosomal system, the Snc v-SNAREs are also required for exocytosis. Unlike most vps mutants, cells lacking Vps45 display multiple growth phenotypes. Here we report that these can be reversed by selectively restoring Snc2 levels in vps45 mutant cells. Our data indicate that as well as functioning as part of the machinery that controls SNARE complex assembly, Vps45 also plays a key role in determining the levels of its cognate SNARE proteins; another key factor in regulation of membrane traffic. 相似文献
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Zhu YF Wilcoxen K Saunders J Guo Z Gao Y Connors PJ Gross TD Tucci FC Struthers RS Reinhart GJ Xie Q Chen C 《Bioorganic & medicinal chemistry letters》2002,12(3):403-406
In the process of developing GnRH receptor antagonists, a novel base-catalyzed cyclization of compounds 5a-b was discovered, which led to the formation of the 2-aryl pyrrolo[1,2-a]pyrimid-7-one core structures 6a-b. These intermediates were further modified at positions 1, 2, 4 and 6 to afford a series of potent GnRH antagonists with low nanomolar K(i) values. 相似文献
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Tucci FC Zhu YF Guo Z Gross TD Connors PJ Struthers RS Reinhart GJ Saunders J Chen C 《Bioorganic & medicinal chemistry letters》2003,13(19):3317-3322
A new class of small molecule GnRH antagonists, the 1-arylmethyl-3-(1-methyl-2-amino)ethyl-5-aryl-6-methyluracils, was designed and a novel stereoselective synthesis for these compounds was developed. The stereochemical integrities of key intermediates (S)-6 and (R)-6 were confirmed by a combination of X-ray crystallography and chiral HPLC determinations. SAR studies were performed, which allowed the identification of derivatives (R)-9f, (R)-9h and (R)-12 as potent hGnRH antagonists (K(i)=20 nM). 相似文献
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