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1.
Vertebrate fossils from many different formations fluoresce when exposed to ultraviolet (UV) light. In this paper field observations and controlled experiments in the Chadron Formation (White River Group, late Eocene) of Wyoming are used to assess the utility of searching for fossils at night using ultraviolet light. The results indicate that, especially for very small teeth and egg-shell fragments, searching with ultraviolet light at night can result in significantly more specimens than searching during daylight hours. This method has the potential to increase sample sizes for small vertebrate specimens that are often overlooked when using standard collecting techniques. 相似文献
2.
Fang Liu Wenqing Li Darin Ridgway Tingyue Gu Zhongyao Shen 《Biotechnology letters》1998,20(4):345-348
Beet molasses successfully replaced glucose as sole carbon source to produce poly--hydroxybutyrate by a recombinant Escherichia coli strain (HMS174/pTZ18u-PHB). The fermentation with molasses was cheaper than with glucose. The final dry cell weight, PHB content and PHB productivity were 39.5 g/L, 80% (w/w) and 1 g/Lh, respectively, in a 5 L stirred tank fermenter after 31.5 h fed-batch fermentation with constant pH and dissolved O2 content. © Rapid Science Ltd. 1998 相似文献
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Olivier Maurin Artemis Anest Sidonie Bellot Edward Biffin Grace Brewer Tristan Charles-Dominique Robyn S. Cowan Steven Dodsworth Niroshini Epitawalage Berta Gallego Augusto Giaretta Renato Goldenberg Deise J.P. Gonçalves Shirley Graham Peter Hoch Fiorella Mazine Yee Wen Low Catherine McGinnie Fabián A. Michelangeli Sarah Morris Darin S. Penneys Oscar Alejandro Pérez Escobar Yohan Pillon Lisa Pokorny Gustavo Shimizu Vanessa G. Staggemeier Andrew H. Thornhill Kyle W. Tomlinson Ian M. Turner Thais Vasconcelos Peter G. Wilson Alexandre R. Zuntini William J. Baker Félix Forest Eve Lucas 《American journal of botany》2021,108(7):1087-1111
5.
Rougier Guillermo W. Gaudin Timothy J. Croft Darin A. 《Journal of Mammalian Evolution》2021,28(4):1021-1025
Journal of Mammalian Evolution - 相似文献
6.
Elizabeth A. Cromwell Jonathan D. King Scott McPherson Falam N. Jip Amy E. Patterson Aryc W. Mosher Darin S. Evans Paul M. Emerson 《PLoS neglected tropical diseases》2013,7(1)
Mass drug administration (MDA) with antibiotics is a key component of the SAFE strategy for trachoma control. Guidelines recommend that where MDA is warranted the whole population be targeted with 80% considered the minimum acceptable coverage. In other countries, MDA is usually conducted by salaried Ministry of Health personnel (MOH). In Plateau State, Nigeria, the existing network of volunteer Community Directed Distributors (CDD) was used for the first trachoma MDA. We conducted a population-based cluster random survey (CRS) of MDA participation to determine the true coverage and compared this to coverage reported from CDD registers. We surveyed 1,791 people from 352 randomly selected households in 24 clusters in three districts in Plateau State in January 2011, following the implementation of MDA. Households were enumerated and all individuals present were asked about MDA participation. Household heads were questioned about household-level characteristics and predictors of participation. Individual responses were compared with the CDD registers. MDA coverage was estimated as 60.3% (95% CI 47.9–73.8%) by the survey compared with 75.8% from administrative program reports. CDD registration books for comparison with responses were available in 19 of the 24 clusters; there was a match for 658/682 (96%) of verifiable responses. CDD registers did not list 481 (41.3%) of the individuals surveyed. Gender and age were not associated with individual participation. Overall MDA coverage was lower than the minimum 80% target. The observed discrepancy between the administrative coverage estimate from program reports and the CRS was largely due to identification of communities missed by the MDA and not reported in the registers. CRS for evaluation of MDA provides a useful additional monitoring tool to CDD registers. These data support modification of distributor training and MDA delivery to increase coverage in subsequent rounds of MDA. 相似文献
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Ismail Hassan Ismail Darin McDonald Hilmar Strickfaden Zhizhong Xu Michael J. Hendzel 《The Journal of biological chemistry》2013,288(37):26944-26954
Polycomb-repressive complex 1 (PRC1)-mediated histone ubiquitylation plays an important role in aberrant gene silencing in human cancers and is a potential target for cancer therapy. Here we show that 2-pyridine-3-yl-methylene-indan-1,3-dione (PRT4165) is a potent inhibitor of PRC1-mediated H2A ubiquitylation in vivo and in vitro. The drug also inhibits the accumulation of all detectable ubiquitin at sites of DNA double-strand breaks (DSBs), the retention of several DNA damage response proteins in foci that form around DSBs, and the repair of the DSBs. In vitro E3 ubiquitin ligase activity assays revealed that PRT4165 inhibits both RNF2 and RING 1A, which are partially redundant paralogues that together account for the E3 ubiquitin ligase activity found in PRC1 complexes, but not RNF8 nor RNF168. Because ubiquitylation is completely inhibited despite the efficient recruitment of RNF8 to DSBs, our results suggest that PRC1-mediated monoubiquitylation is required for subsequent RNF8- and/or RNF168-mediated polyubiquitylation. Our results demonstrate the unique feature of PRT4165 as a novel chromatin-remodeling compound and provide a new tool for the inhibition of ubiquitylation signaling at DNA double-strand breaks. 相似文献
9.
Graciela B. Arhancet Daniel P. Walker Sue Metz Yvette M. Fobian Steven E. Heasley Jeffrey S. Carter John R. Springer Darin E. Jones Michael J. Hayes Alexander F. Shaffer Gina M. Jerome Michael T. Baratta Ben Zweifel William M. Moore Jaime L. Masferrer Michael L. Vazquez 《Bioorganic & medicinal chemistry letters》2013,23(4):1114-1119
Inhibition of mPGES-1, the terminal enzyme in the arachidonic acid/COX pathway to regulate the production of pro-inflammatory prostaglandin PGE2, is considered an attractive new therapeutic target for safe and effective anti-inflammatory drugs. The discovery of a novel series of orally active, selective benzoxazole piperidinecarboxamides as mPGES-1 inhibitors is described. Structure–activity optimization of lead 5 with cyclohexyl carbinols resulted in compound 12, which showed excellent in vitro potency and selectivity against COX-2, and reasonable pharmacokinetic properties. Further SAR studies of the benzoxazole ring substituents lead to a novel series of highly potent compounds with improved PK profile, including 23, 26, and 29, which were effective in a carrageenan-stimulated guinea pig air pouch model of inflammation. Based on its excellent in vitro and in vivo pharmacological, pharmacokinetic and safety profile and ease of synthesis, compound 26 (PF-4693627) was advanced to clinical studies. 相似文献
10.
Daesoo Kim Greg Thoma Darin Nutter Franco Milani Rick Ulrich Greg Norris 《The International Journal of Life Cycle Assessment》2013,18(5):1019-1035