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1.
Tiana J. Preston Sherrie A. Caarels 《Journal of experimental marine biology and ecology》2010,390(2):196-202
We compared the results of two biologging techniques used to study the foraging behaviour of a colony of small inshore predators, little penguins (Eudyptula minor). The first technique involved the use of satellite transmitters and diving loggers deployed on separate individuals, which has been the conventional method of tracking the movements and behaviour of this species for > 10 years. The second technique combined a diving logger and a global positioning system (GPS) logger deployed on the same individual, which is similar to the biologging methods presently being developed and used for many other species. We then considered the value of each technique as a conservation tool operating at the small scale (foraging area < 5000 ha and duration < 1 day).We found that the separately deployed satellite transmitters significantly underestimated the penguins' foraging area size. However, the size of the foraging area and other foraging parameters, such as total distance travelled, were influenced by the degree of GPS location sub-sampling. Furthermore, only the combined diving and GPS loggers could confidently describe the diving behaviour of the penguins in relation to the sea floor and identify that they were using small areas of conservation interest (shipping channel) inside their foraging area.Hence, the method employed to assess habitat use at fine scales can influence conservation measures that rely upon the data collected. We suggest that researchers fast-track their adoption of high resolution multi-loggers for increased data confidence when tracking animals at a fine scale, but also consider the potential effect of sampling rate on the calculation of parameters of interest. 相似文献
2.
Pietranico SL Foley LH Huby N Yun W Dunten P Vermeulen J Wang P Toth K Ramsey G Gubler ML Wertheimer SJ 《Bioorganic & medicinal chemistry letters》2007,17(14):3835-3839
New modifications on the C-8 4-aminobenzyl unit of the previously reported 3-alkyl-1,8-dibenzylxanthine inhibitors of cPEPCK are presented. The most active compound reported here is the 5-chloro-1,3-dimethyl-1H-pyrazole-4-sulfonic acid amide derivative 2 with an IC(50) of 0.29+/-0.08 microM. An X-ray analysis of a heteroaromatic sulfonamide is presented showing a new pi-pi interaction. 相似文献
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4.
The potential of viral contamination is a regulatory concern for continuous cell line-derived pharmaceutical proteins. Complementary and redundant safety steps, including an evaluation of the viral clearance capacity of unit operations in the purification process, are performed prior to registration and marketing of biotechnology pharmaceuticals. Because process refinement is frequently beneficial, CBER/FDA has published guidance facilitating process improvement by delineating specific instances where the bracketing and generic approaches are appropriate for virus removal validation. In this study, a generic/matrix study was performed using Q-Sepharose Fast Flow (QSFF) chromatography to determine if bracketing and generic validation can be applied to anion exchange chromatography. Key operational parameters were varied to upper and lower extreme values and the impact on viral clearance was assessed using simian virus 40 (SV40) as the model virus. Operational ranges for key chromatography parameters were identified where an SV40 log(10) reduction value (LRV) of >or=4.7 log(10) is consistently achieved. On the basis of the apparent robustness of SV40 removal by Q-anion exchange chromatography, we propose that the concept of \"bracketed generic\" validation can be applied to this and potentially other chromatography unit operations. 相似文献
5.
Mathilde Hertz 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1937,25(2):239-250
Zusammenfassung Die Tatsache, daß reflektiertes Tageslicht für die Biene dann neutral oder farblos ist, wenn es in seiner spektralen Zusammensetzung nicht wesentlich von der Zusammensetzung des Sonnenlichtes — soweit dieses den Bienen sichtbar ist — abweicht, bzw. die Tatsache, daß bei mehr oder weniger vollständigem Fehlen von Ultraviolett weißes Licht für die Biene farbig wird, macht bestimmte Vorsichtsmaßregeln im Gebrauch von Farbpapieren, Graupapieren, Glasplatten und Filtergläsern im Bienenversuch notwendig. Solche Vorsichtsmaßregeln sind bisher nicht oder nicht ausreichend beachtet worden. Für die wichtigeren Ergebnisse bleibt das ohne nachteilige Folgen, einige weitere Ergebnisse erscheinen nun zweifelhaft und sollten nachgeprüft werden. 相似文献
6.
Identification of consensus patterns in unaligned DNA sequences known to be functionally related 总被引:16,自引:0,他引:16
Hertz Gerald Z.; Hartzell George W. III; Stormo Gary D. 《Bioinformatics (Oxford, England)》1990,6(2):81-92
We have developed a method for identifying consensus patternsin a set of unaligned DNA sequences known to bind a common proteinor to have some other common biochemical function. The methodis based on a tnatrix representation of binding site patterns.Each row of the matrix represents one of the four possible bases,each column represents one of the positions of the binding siteand each element is determined by the frequency the indicatedbase occurs at the indicated position. The goal of the methodis to find the most significant matrix-i.e. the one with thelowest probability of occurring by chance-out of all the matricesthat can be formed from the set of related sequences. The reliabilityof the method improves with the number of sequences, while thetime required increases only linearly with the number of sequences.To test this method, we analysed 11 DNA sequences containingpromoters regulated by the Escherichia coli LexA protein. Thematrices we' found were consistent with the known consensussequence, and could distinguish the generally accepted LexAbinding sites from other DNA sequences.
Received on November 6, 1989; accepted on December 20, 1989 相似文献
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8.
K R Fisher L Hertz 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1975,149(3):702-706
Neuroepithelial cells of the presumptive spinal cord (stage 11) consume oxygen, albeit at a low rate. As neurons differentiate in the presumptive motor horns the rate of oxygen consumption increases to approximately 70 mumoles/g wet wt/hr by stage 26. It is suggested that the rate of oxygen consumption per unit volume of neuron then remains constant as subsequent development ensues but since the neurons become more widely spaced the oxygen consumption per unit volume of anterior horn tissue decreases. 相似文献
9.
D Sompolinsky J B Hertz N H?iby K Jensen B Mansa Z Samra 《Acta pathologica et microbiologica Scandinavica. Section B, Microbiology》1980,88(3):143-149
In crude water-soluble extracts of Pseudomonas aeruginosa 64 antigens can be demonstrated by crossed immunoelectrophoresis in agarose with polyvalent Pseudomonas-immunoglobulin. One of these antigens cross-reacts with antigens prepared from bacteria of a wide range of taxonomic groups. Monospecific immunoglobulins to this antigen (Common Antigen) were produced by immunization with the appropriate immunocomplex extracted from agarose. Common Antigen was purified by the combination of two fractionation methods: Precipitation of the crude extract with 18% (w/v) sodium sulfate, followed by gel filtration of the supernatant on a Sephadex G-200 column. By this method, 35% of Common Antigen from the crude extract was recovered, more than half of the fractions electrophoretically pure. Electrophoresis of reduced Common Antigen on a dodecyl sodium sulfate polyacrylamide gel revealed two protein bands with apparent molecular weights of 59-62 000 and 62-65 000, respectively. The untreated antigen, however, passed a column of Sephadex G-200 with the void volumen, indicating a substance of high molecular weight (> 4-600 000). 相似文献
10.
Yan Zhang Christine H. Wendt Marshall I. Hertz Gary L. Nelsestuen 《Clinical proteomics》2007,3(1-4):3-12