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121.
Ni L Zheng XS Somers PK Hoong LK Hill RR Marino EM Suen KL Saxena U Meng CQ 《Bioorganic & medicinal chemistry letters》2003,13(4):745-748
alpha,beta-Unsaturated sulfones have been discovered from a combinatorial library as leads for a new series of inhibitors of inducible VCAM-1 expression. Although not essential, further conjugation of the sulfonyl group to another vinyl group or a phenyl group increases the potency dramatically. 相似文献
122.
Genetic characterization of QTL associated with resistance to Fusarium head blight in a doubled-haploid spring wheat population. 总被引:12,自引:0,他引:12
Fusarium head blight (FHB) is one of the most important fungal wheat diseases worldwide. Understanding the genetics of FHB resistance is the key to facilitating the introgression of different FHB resistance genes into adapted wheat. The objectives of the present study were to detect and map quantitative trait loci (QTL) associated with FHB resistance genes and characterize the genetic components of the QTL in a doubled-haploid (DH) spring wheat population using both single-locus and two-locus analysis. A mapping population, consisting of 174 DH lines from the cross between DH181 (resistant) and AC Foremost (susceptible), was evaluated for type I resistance to initial infection during a 2-year period in spray-inoculated field trials, for Type II resistance to fungal spread within the spike in 3 greenhouse experiments using single-floret inoculation, and for resistance to kernel infection in a 2001 field trial. One-locus QTL analysis revealed 7 QTL for type I resistance on chromosome arms 2DS, 3AS, 3BS, 3BC (centromeric), 4DL, 5AS, and 6BS, 4 QTL for type II resistance on chromosomes 2DS, 3BS, 6BS, and 7BL, and 6 QTL for resistance to kernel infection on chromosomes 1DL, 2DS, 3BS, 3BC, 4DL, and 6BS. Two-locus QTL analysis detected 8 QTL with main effects and 4 additive by additive epistatic interactions for FHB resistance and identified novel FHB resistance genes for the first time on chromosomes 1DL, 4AL, and 4DL. Neither significant QTL by environment interactions nor epistatic QTL by environment interactions were found for either type I or type II resistance. The additive effects of QTL explained most of the phenotypic variance for FHB resistance. Marker-assisted selection for the favored alleles at multiple genomic regions appears to be a promising tool to accelerate the introgression and pyramiding of different FHB resistance genes into adapted wheat genetic backgrounds. 相似文献
123.
Jan A. Graf Michael J. Somers Micaela Szykman Gunther Rob Slotow 《Acta theriologica》2009,54(4):333-343
Animal population sizes and trends, as well as their distributions, are essential information to the understanding and conservation
of ecosystems. During this study in Hluhluwe-iMfolozi Park, South Africa, a spotted hyaena Crocuta crocuta Erxleben, 1777 (Hyaenidae) population was surveyed by attracting individuals with pre-recorded sounds. The hyaena population
(excluding cubs) is substantially larger (321 individuals) than the previous estimate of 200 and this population is the second
largest protected population in South Africa. Average hyaena density, at 0.357 individuals/km2, was relatively high compared to other southern African conservation areas, and range from 0 to 1.25 individuals/km2 across sampling stations. For short periods, spatial heterogeneity in density was marked at small and large spatial scales,
but decreased when averaged over a longer period. This heterogeneity may be important in promoting the coexistence of other
large and mobile carnivores in Hluhluwe-iMfolozi Park by creating potential dynamic competition refugia in space and time.
Furthermore, heterogeneity of hyaena density at smaller scales should influence studies investigating the avoidance of hyaenas
by competitively inferior carnivores. 相似文献
124.
Sandra Skowronek Michael Ewald Maike Isermann Ruben Van De Kerchove Jonathan Lenoir Raf Aerts Jens Warrie Tarek Hattab Olivier Honnay Sebastian Schmidtlein Duccio Rocchini Ben Somers Hannes Feilhauer 《Biological invasions》2017,19(1):239-254
Reliable distribution maps are crucial for the management of invasive plant species. An alternative to traditional field surveys is the use of remote sensing data, which allows coverage of large areas. However, most remote sensing studies on invasive plant species focus on mapping large stands of easily detectable study species. In this study, we used hyperspectral remote sensing data in combination with field data to derive a distribution map of an invasive bryophyte species, Campylopus introflexus, on the island of Sylt in Northern Germany. We collected plant cover data on 57 plots to calibrate the model and presence/absence data of C. introflexus on another 150 plots for independent validation. We simultaneously acquired airborne hyperspectral (APEX) images during summer 2014, providing 285 spectral bands. We used a Maxent modelling approach to map the distribution of C. introflexus. Although C. introflexus is a small and inconspicuous species, we were able to map its distribution with an overall accuracy of 75 %. Reducing the sampling effort from 57 to 7 plots, our models performed fairly well until sampling effort dropped below 12 plots. The model predicts that C. introflexus is present in about one quarter of the pixels in our study area. The highest percentage of C. introflexus is predicted in the dune grassland. Our findings suggest that hyperspectral remote sensing data have the potential to provide reliable information about the degree of bryophyte invasion, and thus provide an alternative to traditional field mapping approaches over large areas. 相似文献
125.
126.
Sally C. Hunter Markus Gusset Lance J. Miller Michael J. Somers 《Journal of applied animal welfare science : JAAWS》2014,17(2):98-110
A clear understanding of space use is required to more fully understand biological requirements of nonhuman animals in zoos, aid the design of exhibits, and maximize the animals' welfare. This study used electivity indexes to assess space use of two packs of African wild dogs (Lycaon pictus) and the appropriateness of two naturalistic, outdoor enclosures at the San Diego Zoo and Bronx Zoo. The results identified enclosure features that were both underutilized and overutilized. They suggest that replacing underutilized areas with features similar to areas that were overutilized may provide more preferred opportunities for the animals. Assessing space use of animals in human care may serve as an indicator of enclosure appropriateness and could have welfare implications. By looking at the possible reasons for area preferences, animal managers can get an idea of where improvements could be made. Designing future exhibits accordingly thus can provide possible welfare benefits for the animals concerned. 相似文献
127.
Habitat specificity of littoral Chydoridae (Crustacea,Branchiopoda, Anomopoda) in Plastic Lake,Ontario, Canada 总被引:2,自引:2,他引:0
Tremel Birgitta Frey S.E. Yan Norman D. Somers Keith M. Pawson Trevor W. 《Hydrobiologia》2000,432(1-3):195-205
This study identified two scales of pattern in the assemblages of Chydoridae (Crustacea, Branchiopoda, Anomopoda) in the shallow (<2 m) littoral zone of Plastic Lake, Ontario, Canada in the autumn of 1987. Twenty chydorid species were collected in 15 over-night sets of funnel traps in each of four habitat types. Analysis of variance multivariate analysis of variance, and discriminant function analysis revealed that assemblages differed among the habitats. Alona intermedia, Alona quadrangularis and Chydorus bicornutus were particularly abundant in the most structurally diverse habitat type – muddy, rock-strewn areas with approximately 40% bottom cover by the pipewort, Eriocaulon septangulare. In contrast, Anchistropus cf. minor was caught most often on bare shelves of rock. A second set of analyses demonstrated that chydorid assemblages also differed at a smaller scale, i.e. with local patchiness in bottom cover by the dominant macrophyte (E. septangulare). The abundance of Alona affinis was positively correlated with cover by E. septangulare, whereas Anchistropus cf. minor was caught mainly in microhabitats without vegetation. Alona intermedia and A. quadrangularis were most abundant in microhabitats with intermediate amounts of vegetation, suggesting their abundance is influenced by habitat factors other than vegetation. 相似文献
128.
Angell RM Atkinson FL Brown MJ Chuang TT Christopher JA Cichy-Knight M Dunn AK Hightower KE Malkakorpi S Musgrave JR Neu M Rowland P Shea RL Smith JL Somers DO Thomas SA Thompson G Wang R 《Bioorganic & medicinal chemistry letters》2007,17(5):1296-1301
The identification and exploration of a novel, potent and selective series of N-(3-cyano-4,5,6,7-tetrahydro-1-benzothien-2-yl)amide inhibitors of JNK2 and JNK3 kinases is described. Compounds 5a and 11a were identified as potent inhibitors of JNK3 (pIC50 6.7 and 6.6, respectively), with essentially equal potency against JNK2 (pIC50 6.5). Selectivity within the mitogen-activated protein kinase (MAPK) family, against JNK1, p38alpha and ERK2, was observed for the series. X-ray crystallography of 5e and 8a in JNK3 revealed a unique binding mode, with the 3-cyano substituent forming an H-bond acceptor interaction with the hinge region of the ATP-binding site. 相似文献
129.
130.
Molecular detection of QTLs for agronomic and quality traits in a doubled haploid population derived from two Canadian wheats (Triticum aestivum L.) 总被引:13,自引:0,他引:13
Huang XQ Cloutier S Lycar L Radovanovic N Humphreys DG Noll JS Somers DJ Brown PD 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,113(4):753-766
Development of high-yielding wheat varieties with good end-use quality has always been a major concern for wheat breeders. To genetically dissect quantitative trait loci (QTLs) for yield-related traits such as grain yield, plant height, maturity, lodging, test weight and thousand-grain weight, and for quality traits such as grain and flour protein content, gluten strength as evaluated by mixograph and SDS sedimentation volume, an F1-derived doubled haploid (DH) population of 185 individuals was developed from a cross between a Canadian wheat variety “AC Karma” and a breeding line 87E03-S2B1. A genetic map was constructed based on 167 marker loci, consisting of 160 microsatellite loci, three HMW glutenin subunit loci: Glu-A1, Glu-B1 and Glu-D1, and four STS-PCR markers. Data for investigated traits were collected from three to four environments in Manitoba, Canada. QTL analyses were performed using composite interval mapping. A total of 50 QTLs were detected, 24 for agronomic traits and 26 for quality-related traits. Many QTLs for correlated traits were mapped in the same genomic regions forming QTL clusters. The largest QTL clusters, consisting of up to nine QTLs, were found on chromosomes 1D and 4D. HMW glutenin subunits at Glu-1 loci had the largest effect on breadmaking quality; however, other genomic regions also contributed genetically to breadmaking quality. QTLs detected in the present study are compared with other QTL analyses in wheat. 相似文献