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131.
132.
Summary Crossbred calves (Bos taurus × Bos indicus) were repeatedly infested with the ixodid tick,Hyalomma anatolicum anatolicum. The parameters of engorgement, pre-oviposition period, oviposition period, engorged weight, egg batch weight, and per cent
hatch of eggs all showed statistically significant differences between first to tenth infestation. Only the time to engorgement
did not change. It is concluded that repeated infestations of this tick stimulate acquired resistance.
Resumen Terrneros cruzadosBos taurus × Bos indicus se infestaron de manera natural. Con la grrapata ixodes,Hyalomma anatolicum anatolicum. Los parámetros medidos de ingurgitación, período de pre-oviposición, período de oviposición, peso de ingurgitación, peso del bache de huevos puestos y el porcentaje de eclosión de los mismos, presentaron diferencias estadísticamente significativas entre la primera y décima infestación. Lo único que no cambió fue el tiempo de ingurgitación. Se sugiere que la infestación repetida de esta garrapata, estimula la resistencia adquirida.
Résumé Des veaux issue de croisementsBos taurus × Bos indicus ont été soumis à une infestation répétée parHyalomma anatolicum anatolicum. Les paramètres suivants: gorgement, périodes de préet d'oviposition, poids en fin de gorgement, poids du lot de ponte et pourcentage d'oeufs éclos, ont tous montré des différences significatives entre la première et la dixième infestation; seule la durée de gorgement n'a pas varié. Les auteurs concluement que les infestations répétées par cette tique stimulent la résistance acquise des veaux.相似文献
133.
S. Adhikary D. K. Bagchi P. Ghosal R. N. Banerjee B. N. Chatterjee 《Journal of Agronomy and Crop Science》1991,167(5):289-293
To examine the advantages of cereal-legume intercropping system with maize as main crops, field studies conducted for two years on sandy upland loamy soils in Bihar plateau, India, indicated maize-groundnut as the best system. Yield advantages were noticed between 22–44 % over sole maize cropping. Different production indices largely indicated the same pattern in ranking intercropping treatments. Of the other legumes used, mung also showed potential whereas cowpea and soyabean did not. Increasing cropping intensities through use of interspace by legume did not significantly reduce maize yield, particularly in combination with groundnut and mung. Soil nitrogen enrichment through legume cultivation could be noted through examination of soil test values and yield of succeeding wheat crop. Wheat, however, did not show its promise as a follow-up crop without input of water and fertilizer. 相似文献
134.
New detrital-zircon geochronologic data reveal that a through-going paleoriver connected Texas with Nevada in Late Triassic time. Sandstone from the Upper Triassic Santa Rosa Sandstone (Dockum Group) from northwestern Texas contains a detrital zircon suite nearly identical to that found in western Nevada in the Upper Triassic Osobb Formation (Auld Lang Syne Group, correlative with the Chinle Formation). The Santa Rosa Sandstone was derived in large part from the eroded Cambrian core of the Amarillo-Wichita uplift, as evidenced by abundant zircons with ages of 515 to 525 million years. Other zircon grains in the sandstone are Permian, Devonian, Proterozoic, and Archean in age and, with the exception of the Archean grain, are also matched by the population in the Nevada strata. 相似文献
135.
High-throughput synthesis of zeolitic imidazolate frameworks and application to CO2 capture 总被引:2,自引:0,他引:2
Banerjee R Phan A Wang B Knobler C Furukawa H O'Keeffe M Yaghi OM 《Science (New York, N.Y.)》2008,319(5865):939-943
A high-throughput protocol was developed for the synthesis of zeolitic imidazolate frameworks (ZIFs). Twenty-five different ZIF crystals were synthesized from only 9600 microreactions of either zinc(II)/cobalt(II) and imidazolate/imidazolate-type linkers. All of the ZIF structures have tetrahedral frameworks: 10 of which have two different links (heterolinks), 16 of which are previously unobserved compositions and structures, and 5 of which have topologies as yet unobserved in zeolites. Members of a selection of these ZIFs (termed ZIF-68, ZIF-69, and ZIF-70) have high thermal stability (up to 390 degrees C) and chemical stability in refluxing organic and aqueous media. Their frameworks have high porosity (with surface areas up to 1970 square meters per gram), and they exhibit unusual selectivity for CO2 capture from CO2/CO mixtures and extraordinary capacity for storing CO2: 1 liter of ZIF-69 can hold approximately 83 liters of CO2 at 273 kelvin under ambient pressure. 相似文献
136.
Rajarshi Guhaniyogi Andrew O. Finley Sudipto Banerjee Richard K. Kobe 《Journal of Agricultural, Biological & Environmental Statistics》2013,18(3):274-298
Advances in geo-spatial technologies have created data-rich environments which provide extraordinary opportunities to understand the complexity of large and spatially indexed data in ecology and the natural sciences. Our current application concerns analysis of soil nutrients data collected at La Selva Biological Station, Costa Rica, where inferential interest lies in capturing the spatially varying relationships among the nutrients. The objective here is to interpolate not just the nutrients across space, but also associations among the nutrients that are posited to vary spatially. This requires spatially varying cross-covariance models. Fully process-based specifications using matrix-variate processes are theoretically attractive but computationally prohibitive. Here we develop fully process-based low-rank but non-degenerate spatially varying cross-covariance processes that can effectively yield interpolate cross-covariances at arbitrary locations. We show how a particular low-rank process, the predictive process, which has been widely used to model large geostatistical datasets, can be effectively deployed to model non-degenerate cross-covariance processes. We produce substantive inferential tools such as maps of nonstationary cross-covariances that constitute the premise of further mechanistic modeling and have hitherto not been easily available for environmental scientists and ecologists. 相似文献
137.
Genetic Resources and Crop Evolution - Genomic Selection (GS) is a breeding technique that utilizes whole genome markers to make trait predictions. The goal of GS is to identify the top candidates... 相似文献
138.
AIM: To investigate risk factors for injury to musculoskeletal structures of the lower fore- and hind-limbs of Thoroughbred horses training and racing in New Zealand. METHODS: A case-control study analysed by logistic regression was used to compare explanatory variables for musculoskeletal injuries (MSI) in racehorses. The first dataset, termed the Training dataset, involved 459 first-occurrence cases of lower-limb MSI in horses in training, and the second, the Starting dataset, comprised a subset of those horses that had started in at least one trial or race in the training preparation that ended with MSI (n=294). All training preparations for horses that did not suffer from MSI for which complete data were available were used in the analyses as controls, and provided 2,181 and 1,639 preparations for the Training and Starting datasets, respectively. Multivariate logistic regression was used to evaluate risk factors, and results were reported as odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Horses aged ≥5 years were at higher risk of injury than 2-year-olds. Elevated odds of MSI occurred in horses in the Starting dataset that were training in the 1997–1998 year compared with the 1999–2000 year, and in those horses where trials comprised >20% of all starts in a preparation. Training preparations that ended in winter, and horses in their third or later training preparation, had lower odds of MSI compared with those ending in other seasons or the first preparation, respectively. Reduced odds of MSI were observed in preparations in which starts occurred compared with those that had no starts, and in the Starting dataset, preparations that included more than one start had a reduced likelihood of MSI compared with preparations that had only one start. In the Training dataset, preparations longer than 20 weeks were associated with reduced odds of MSI compared with those shorter than 20 weeks. Cumulative racing distance in the last 30 days of a training preparation was best modelled with linear and quadratic terms. Results indicated that increasing cumulative racing distances were associated with an initial reduction in the odds of MSI that then levelled out and finally appeared to increase again as the explanatory variable continued to increase. The risk of MSI varied significantly between trainers. CONCLUSION: This study identified intrinsic (age) and extrinsic risk factors for MSI in training and racing Thoroughbreds in New Zealand. The risk of MSI initially decreased, then increased, as cumulative racing distance increased. Significant variation between trainers indicated management and training methods influence the risk of MSI. 相似文献
139.
Crossbred calves (Bos indicus×Bos taurus) were immunized with a fractionated midgut supernate antigen (GS-F Ag from Hyalomma anatolicum anatolicum). The first inoculation on day 0 was given intramuscularly after emulsification with Freund's complete adjuvant; the second was given subcutaneously on day 14 in incomplete Freund's adjuvant; and the third on day 35 was given subcutaneously without adjuvant. Each injection comprised 1 mg of antigen protein. Ten days after the last inoculation, the immunized calves were challenged simultaneously with 1000 larvae and 20 pairs (20 males and 20 females) of adult H. a. anatolicum on one ear and a similar number of Hyalomma dromedarii ticks on the other ear. There was a significant decrease in the percentage larval engorgement and larval rejection of up to 34% on the immunized calves. A significant increase in the engorgement and preoviposition periods and a significant decrease in the engorged weight, egg mass weight and reproductive index were observed for adult female ticks when fed on the immunized calves. The GS-F Ag also induced a considerable degree of cross-protection in calves against H. dromedarii larval ticks. 相似文献
140.
ABSTRACT The biological and molecular properties of Tomato leaf curl Gujarat virus from Varanasi, India (ToLCGV-[Var]) were characterized. ToLCGV-[Var] could be transmitted by grafting and through whitefly transmission in a persistent manner. The full-length genome of DNA-A and DNA-B of ToLCGV-[Var] was cloned in pUC18. Sequence analysis revealed that DNA-A (AY190290) is 2,757 bp and DNA-B (AY190291) is 2,688 bp in length. ToLCGV-[Var] could infect and cause symptoms in tomato, pepper, Nicotiana benthamiana, and N. tabacum when partial tandem dimeric constructs of DNA-A and DNA-B were co-inoculated by particle bombardment. DNA-A alone also is infectious, but symptoms were milder and took longer to develop. ToLCGV-Var virus can be transmitted through sap inoculation from infected tomato plants to the above-mentioned hosts causing the same symptoms. Open reading frames (ORFs) in both DNA-A and DNA-B are organized similarly to those in other begomoviruses. DNA-A and DNA-B share a common region of 155 bp with only 60% sequence identity. DNA-B of ToLCGV-[Var] shares overall 80% identity with DNA-B of Tomato leaf curl New Delhi virus-Severe (ToLCNDV-Svr) and 75% with ToLCNDV-[Lucknow] (ToLCNDV-[Luc]). Comparison of DNA-A sequence with different begomoviruses indicates that ToLCGV-[Var] shares 84% identity with Tomato leaf curl Karnataka virus (ToLCKV) and 66% with ToLCNDV-Svr. ToLCGV-[Var] shares a maximum of 98% identity with another isolate of the same region (ToLCGV-[Mir]; AF449999) and 97% identity with one isolate from Gujarat (ToLCGV-[Vad]; AF413671). All three viruses belong to the same species that is distinct from all the other geminivirus species described so far in the genus Begomovirus of the family Geminiviridae. The name Tomato leaf curl Gujarat virus is proposed because the first sequence was taken from an isolate of Gujarat, India. 相似文献