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排序方式: 共有188条查询结果,搜索用时 15 毫秒
21.
Minimising noise disturbance during ground shooting of pest animals through the use of a muzzle blast suppressor/silencer 下载免费PDF全文
Warwick Williams Adam McSorley Rob Hunt Grant Eccles 《Ecological Management & Restoration》2018,19(2):172-175
Lethal control of vertebrate animals through the use of firearms is a component of land management in Australia. The reduction in muzzle blast noise in the area surrounding the shooter provides the opportunity to decrease disturbance of nontargeted animals and nearby humans. This study identifies the reduction in environmental noise footprint provided by suppressor use. This suggests that the use of a suppressor to reduce noise from the muzzle blast may increase operational effectiveness of ground shooting while minimising adverse environmental effects. 相似文献
22.
Fleur E van de Geijn Manfred Wuhrer Maurice HJ Selman Sten P Willemsen Ya?l A de Man André M Deelder Johanna MW Hazes Radboud JEM Dolhain 《Arthritis research & therapy》2009,11(6):R193
Introduction
Improvement of rheumatoid arthritis (RA) during pregnancy has been causatively associated with increased galactosylation of immunoglobulin G (IgG) N-glycans. Since previous studies were small, did not include the postpartum flare and did not study sialylation, these issues were addressed in the present study. 相似文献23.
Paul M Kulesa Jessica M Teddy Miranda Smith Richard Alexander Cameron HJ Cooper Rusty Lansford Rebecca McLennan 《BMC developmental biology》2010,10(1):101
Background
Tracing cell dynamics in the embryo becomes tremendously difficult when cell trajectories cross in space and time and tissue density obscure individual cell borders. Here, we used the chick neural crest (NC) as a model to test multicolor cell labeling and multispectral confocal imaging strategies to overcome these roadblocks. 相似文献24.
He SM Wathier M Podzelinska K Wong M McSorley FR Asfaw A Hove-Jensen B Jia Z Zechel DL 《Biochemistry》2011,50(40):8603-8615
PhnP is a phosphodiesterase that plays an important role within the bacterial carbon-phosphorus lyase (CP-lyase) pathway by recycling a "dead-end" intermediate, 5-phospho-α-d-ribosyl 1,2-cyclic phosphate, that is formed during organophosphonate catabolism. As a member of the metallo-β-lactamase superfamily, PhnP is most homologous in sequence and structure to tRNase Z phosphodiesterases. X-ray structural analysis of PhnP complexed with orthovanadate to 1.5 ? resolution revealed this inhibitor bound in a tetrahedral geometry by the two catalytic manganese ions and the putative general acid residue H200. Guided by this structure, we probed the contributions of first- and second-sphere active site residues to catalysis and metal ion binding by site-directed mutagenesis, kinetic analysis, and ICP-MS. Alteration of H200 to alanine resulted in a 6-33-fold decrease in k(cat)/K(M) with substituted methyl phenylphosphate diesters with leaving group pK(a) values ranging from 4 to 8.4. With bis(p-nitrophenyl)phosphate as a substrate, there was a 10-fold decrease in k(cat)/K(M), primarily the result of a large increase in K(M). Moreover, the nickel ion-activated H200A PhnP displayed a bell-shaped pH dependence for k(cat)/K(M) with pK(a) values (pK(a1) = 6.3; pK(a2) = 7.8) that were comparable to those of the wild-type enzyme (pK(a1) = 6.5; pK(a2) = 7.8). Such modest effects are counter to what is expected for a general acid catalyst and suggest an alternate role for H200 in this enzyme. A Br?nsted analysis of the PhnP reaction with a series of substituted phenyl methyl phosphate esters yielded a linear correlation, a β(lg) of -1.06 ± 0.1, and a Leffler α value of 0.61, consistent with a synchronous transition state for phosphoryl transfer. On the basis of these data, we propose a mechanism for PhnP. 相似文献
25.
McSorley R 《Journal of nematology》2011,43(2):63-68
Issues of the Journal of Nematology from 1969-2009 were examined to determine trends in authorship and subject matter. Data were collected on authors, affiliations, locations, funding, nematodes, and nematological subject matter, and then compared among the 4 decades involved. Some of the more prominent changes noted included: a decrease (P < 0.05) in the number of papers published in the Journal of Nematology in the 1990s and 2000s from a peak in the 1980s; an increase (P < 0.05) in number of authors per paper in each decade; an increased (P < 0.05) percentage of international authors in the 1990s and 2000s compared to 1970s; and changing roles of the United States Department of Agriculture (USDA) and different states over a period of 4 decades. Plant-parasitic nematodes were the main organisms studied in 73.4% of all papers published the Journal of Nematology from 1969-2009. The greatest changes in subject matter were increases in papers on biological control and resistance in the 1990s and 2000s compared to the 1970s and 1980s. Additional trends and subjects are discussed, and data are provided comparing differences among the 4 decades for various aspects of nematology. 相似文献
26.
Background
The accuracy of genomic prediction depends largely on the number of animals with phenotypes and genotypes. In some industries, such as sheep and beef cattle, data are often available from a mixture of breeds, multiple strains within a breed or from crossbred animals. The objective of this study was to compare the accuracy of genomic prediction for several economically important traits in sheep when using data from purebreds, crossbreds or a combination of those in a reference population.Methods
The reference populations were purebred Merinos, crossbreds of Border Leicester (BL), Poll Dorset (PD) or White Suffolk (WS) with Merinos and combinations of purebred and crossbred animals. Genomic breeding values (GBV) were calculated based on genomic best linear unbiased prediction (GBLUP), using a genomic relationship matrix calculated based on 48 599 Ovine SNP (single nucleotide polymorphisms) genotypes. The accuracy of GBV was assessed in a group of purebred industry sires based on the correlation coefficient between GBV and accurate estimated breeding values based on progeny records.Results
The accuracy of GBV for Merino sires increased with a larger purebred Merino reference population, but decreased when a large purebred Merino reference population was augmented with records from crossbred animals. The GBV accuracy for BL, PD and WS breeds based on crossbred data was the same or tended to decrease when more purebred Merinos were added to the crossbred reference population. The prediction accuracy for a particular breed was close to zero when the reference population did not contain any haplotypes of the target breed, except for some low accuracies that were obtained when predicting PD from WS and vice versa.Conclusions
This study demonstrates that crossbred animals can be used for genomic prediction of purebred animals using 50 k SNP marker density and GBLUP, but crossbred data provided lower accuracy than purebred data. Including data from distant breeds in a reference population had a neutral to slightly negative effect on the accuracy of genomic prediction. Accounting for differences in marker allele frequencies between breeds had only a small effect on the accuracy of genomic prediction from crossbred or combined crossbred and purebred reference populations. 相似文献27.
The small-subunit ribosomal RNA gene sequences from the hypotrichous ciliates Oxytricha nova and Stylonychia pustulata 总被引:17,自引:0,他引:17
We have determined the complete nucleotide sequence of the small- subunit
ribosomal RNA genes for the ciliate protozoans Stylonychia pustulata and
Oxytricha nova. The sequences are homologous and sufficiently similar that
these organisms must be closely related. In a phylogeny inferred from
comparisons of several eukaryotic small-subunit ribosomal RNAs, the
divergence of the ciliates from the eukaryotic line of descent is seen to
coincide with the radiation of the plants, the animals, and the fungi. This
radiation is preceded by the divergence of the slime mold, Dictyostelium
discoideum.
相似文献
28.
29.
DNA damage‐induced replication stress results in PA200‐proteasome‐mediated degradation of acetylated histones 下载免费PDF全文
30.