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91.
Ellis DA Blazel JK Webber SE Tran CV Dragovich PS Sun Z Ruebsam F McGuire HM Xiang AX Zhao J Li LS Zhou Y Han Q Kissinger CR Showalter RE Lardy M Shah AM Tsan M Patel R LeBrun LA Kamran R Bartkowski DM Nolan TG Norris DA Sergeeva MV Kirkovsky L 《Bioorganic & medicinal chemistry letters》2008,18(16):4628-4632
4-(1,1-Dioxo-1,4-dihydro-1lambda(6)-benzo[1,4]thiazin-3-yl)-5-hydroxy-2H-pyridazin-3-one analogs were discovered as a novel class of inhibitors of HCV NS5B polymerase. Structure-based design led to the identification of compound 3a that displayed potent inhibitory activities in biochemical and replicon assays (1b IC(50)<10 nM; 1b EC(50)=1.1 nM) as well as good stability toward human liver microsomes (HLM t(1/2)>60 min). 相似文献
92.
Population sizes of ice‐associated pinnipeds have often been estimated with visual or photographic aerial surveys, but these methods require relatively slow speeds and low altitudes, limiting the area they can cover. Recent developments in infrared imagery and its integration with digital photography could allow substantially larger areas to be surveyed and more accurate enumeration of individuals, thereby solving major problems with previous survey methods. We conducted a trial survey in April 2003 to estimate the number of Pacific walruses (Odobenus rosmarus divergens) hauled out on sea ice around St. Lawrence Island, Alaska. The survey used high altitude infrared imagery to detect groups of walruses on strip transects. Low altitude digital photography was used to determine the number of walruses in a sample of detected groups and calibrate the infrared imagery for estimating the total number of walruses. We propose a survey design incorporating this approach with satellite radio telemetry to estimate the proportion of the population in the water and additional low‐level flights to estimate the proportion of the hauled‐out population in groups too small to be detected in the infrared imagery. We believe that this approach offers the potential for obtaining reliable population estimates for walruses and other ice‐associated pinnipeds. 相似文献
93.
Richard J. Thomas Daniel Webber William Sellors Aaron Collinge Andrew Frost Anthony J. Stagg Stephen C. Bailey Pramukh N. Jayasekera Rosa R. Taylor Steve Eley Richard W. Titball 《Aerobiologia》2009,25(2):75-84
Flow-focussing technology was harnessed to enable generation of large droplet aerosols within high-level microbiological containment.
The Collison nebuliser and flow-focussing aerosol generator (FFAG) produced aerosols from distilled water with average mass
median aerodynamic diameters (MMAD) of 4.19 and 11.93 μm, respectively. The medium type [water, phosphate buffered saline
(PBS) or microbiological broth] had minimal effect on the droplet size generated by the FFAG. The FFAG can be modulated to
generate reproducible aerosols with a wide range of MMADs (9–105 μm). The number of particulates (i.e. fluospheres) contained
within the droplets increased as the MMAD increased from 12 to 50 μm. The technology described can be used for the exposure
of small-animal models to large droplet aerosols (>10 μm) and has applications in healthcare, pharmaceutical, agricultural
and biodefence environments. 相似文献
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96.
The energy produced from the investment in biofuel crops needs to account for the environmental impacts on soil, water, climate change and ecosystem services. A regionalized approach is needed to evaluate the environmental costs of large-scale biofuel production. We present a regional pan-European simulation of rapeseed ( Brassica napus ) cultivation. Rapeseed is the European Union's dominant biofuel crop with a share of about 80% of the feedstock. To improve the assessment of the environmental impact of this biodiesel production, we performed a pan-European simulation of rapeseed cultivation at a 10 × 10 km scale with Environmental Policy Integrated Climate (EPIC). The model runs with a daily time step and model input consists of spatialized meteorological measurements, and topographic, soil, land use, and farm management practices data and information. Default EPIC model parameters were calibrated based on literature. Modelled rapeseed yields were satisfactory compared with yields at regional level reported for 151 regions obtained for the period from 1995 to 2003 for 27 European Union member countries, along with consistent modelled and reported yield responses to precipitation, radiation and vapour pressure deficit at regional level. The model is currently set up so that plant nutrient stress is not occurring. Total fertilizer consumption at country level was compared with IFA/FAO data. This approach allows us to evaluate environmental pressures and efficiencies arising from and associated with rapeseed cultivation to further complete the environmental balance of biofuel production and consumption. 相似文献
97.
ZHENZHEN YI WEIBO SONG THORSTEN STOECK KHALED A. S. AL‐RASHEID ABDULAZIZ A. AL‐KHEDHAIRY JUN GONG HONGWEI MA ZIGUI CHEN 《Zoological Journal of the Linnean Society》2009,157(2):227-236
The morphologically unique ciliate Psammomitra has long been considered as a systematically uncertain stichotrich. This is mainly because of its highly specialized morphology and a lack of either detailed information concerning its ontogenesis, or molecular data. Based on the small subunit rRNA (SSrRNA) gene and alpha‐tubulin gene sequences, we re‐evaluated the phylogenetic position of Psammomitra retractilis using multiple algorithms. Phylogenetic trees inferred from the SSrRNA gene sequences representing a total of 53 spirotrichs demonstrated the closest relationship of Psammomitra was with Holosticha‐like taxa, with strong support, which clearly suggested that Psammomitra should be placed into the order Urostylida although it branched at a rather deep level, and is likely to be closely related to Holostichidae. With consideration to molecular evidence and morphological characters, Psammomitra should be a clearly outlined taxon at about the rank of family, i.e. Psammomitridae stat. nov. , within the order Urostylida. The improved diagnosis for this family is as follows: Urostylida possessing extremely contractile, elongated body which consists of three parts: head, trunk, and slender tail; midventral complex composed of midventral pairs only and restricted to about anterior 1/3 of ventral surface; frontal, frontoterminal, and transverse cirri present; one left and one right marginal rows which commence near proximal end of adoral zone and extend to near rear body end. 相似文献
98.
Carlos García-Estrada Inmaculada Vaca Ricardo V Ullán Marco A van den Berg Roel AL Bovenberg Juan Francisco Martín 《BMC microbiology》2009,9(1):104-15
Background
Penicillium chrysogenum converts isopenicillin N (IPN) into hydrophobic penicillins by means of the peroxisomal IPN acyltransferase (IAT), which is encoded by the penDE gene. In silico analysis of the P. chrysogenum genome revealed the presence of a gene, Pc13g09140, initially described as paralogue of the IAT-encoding penDE gene. We have termed this gene ial because it encodes a protein with high similarity to IAT (IAL for IAT-Like). We have conducted an investigation to characterize the ial gene and to determine the role of the IAL protein in the penicillin biosynthetic pathway. 相似文献99.
Caleb Webber Jayne Y. Hehir-Kwa Duc-Quang Nguyen Bert B. A. de Vries Joris A. Veltman Chris P. Ponting 《PLoS genetics》2009,5(6)
Rare copy number variants (CNVs) are frequently associated with common neurological disorders such as mental retardation (MR; learning disability), autism, and schizophrenia. CNV screening in clinical practice is limited because pathological CNVs cannot be distinguished routinely from benign CNVs, and because genes underlying patients'' phenotypes remain largely unknown. Here, we present a novel, statistically robust approach that forges links between 148 MR–associated CNVs and phenotypes from ∼5,000 mouse gene knockout experiments. These CNVs were found to be significantly enriched in two classes of genes, those whose mouse orthologues, when disrupted, result in either abnormal axon or dopaminergic neuron morphologies. Additional enrichments highlighted correspondences between relevant mouse phenotypes and secondary presentations such as brain abnormality, cleft palate, and seizures. The strength of these phenotype enrichments (>100% increases) greatly exceeded molecular annotations (<30% increases) and allowed the identification of 78 genes that may contribute to MR and associated phenotypes. This study is the first to demonstrate how the power of mouse knockout data can be systematically exploited to better understand genetically heterogeneous neurological disorders. 相似文献
100.
Heather L. Hartline‐Grafton Donald Rose Carolyn C. Johnson Janet C. Rice Larry S. Webber 《Obesity (Silver Spring, Md.)》2010,18(4):736-742
Many health practitioners recommend eating small, frequent meals for weight loss, yet the relationship of eating patterns, such as eating occasion frequency (EOF), to energy intake and body weight is controversial. Broad‐based efforts to promote worksite wellness programs increase the importance of this issue, as many work environments inherently restrict eating patterns. The eating patterns of school personnel are understudied, but are of particular interest, not only because they have limited eating opportunities during the day but also because their diet and weight outcomes are likely to influence behaviors of a much larger population. We examined relationships between weekday EOF and energy intake and BMI among female elementary school personnel in 22 schools in a suburban county of southeastern Louisiana. Two 24‐h dietary recalls were administered to randomly‐selected employees (n = 329) on nonconsecutive days by registered dietitians. Measured heights and weights were used to calculate BMI (weight/height2). On average, employees consumed 2.2 of their total 5.9 meals and snacks during the school day, accounting for 37% of daily energy. In multiple regression models controlling for demographic and health variables, EOF as well as separate counts of meal and snack frequency were each positively and significantly associated with energy intake. However, neither the number of meals, snacks, nor overall EOF was associated with BMI. The proportion of energy consumed during the school day and the positive association of weekday EOF with energy intake suggest an important role for worksite wellness programs that target the dietary improvement of elementary school personnel. 相似文献