Exploiting New Technologies in Animal Breeding     

Wesley K Whitten 《Australian veterinary journal》1991,68(3):84-84

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Variation in diosgenin levels among 10 accessions of fenugreek seeds produced in western Canada   总被引：1，自引：0，他引：1  

Taylor WG  Zulyniak HJ  Richards KW  Acharya SN  Bittman S  Elder JL 《Journal of agricultural and food chemistry》2002,50(21):5994-5997

A collection of 10 accessions of fenugreek (Trigonella foenum-graecum L.), an annual legume, was grown during two summers at three plot locations in western Canada to assess whether genetic (accession) and environmental factors (site and year of production) influenced levels of diosgenin, a steroidal sapogenin. The 60 harvested seed samples, each analyzed by single determinations on three subsamples of defatted and dried seed material, were hydrolyzed by a microscale procedure in water containing 2-propanol (70%) and sulfuric acid (1 M). The extracts were analyzed by capillary gas chromatography with 6-methyldiosgenin as internal standard. Diosgenin levels from mature seeds ranged from 0.28 to 0.92% (28-92 microg/10 mg). Analysis of variance on combined diosgenin levels from the three sites and two years revealed that accession, accession x year, and site x year effects were significant for diosgenin content, whereas site, year, and site x accession effects were not. Four accessions, CN 19062, CN 19067, CN 19070, and CN 19071, were identified with high levels of diosgenin on the basis of the 2-year data set. In these accessions, mean levels of diosgenin plus yamogenin from seven site years were estimated at 0.70, 0.98, 0.84, and 0.87%, respectively.  相似文献   

Professor Hastings's theory of the corona     

Wesley WH 《Science (New York, N.Y.)》1885,5(123):474-475

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Planetary science. Human space exploration is about more than just science     

Huntress WT 《Science (New York, N.Y.)》2003,301(5634):771

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Book reviews     

Christopher Vecsey  Lawrence Busch  Robert E. Mazur  S. 'Tunji Titilola  Joel Schor  Don F. Hadwiger  E. Wesley F. Peterson  Lorraine Garkovich  Scott R. Collard  Tony Smith 《Agriculture and Human Values》1990,7(3-4):107-131

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Science and law. View from the bench: patents and material transfers     

Walsh JP  Cho C  Cohen WM 《Science (New York, N.Y.)》2005,309(5743):2002-2003

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Bayesian estimation of cluster-level test accuracy based on different sampling schemes     

Chun-Lung Su  Ian A. Gardner  Wesley O. Johnson 《Journal of Agricultural, Biological & Environmental Statistics》2007,12(2):250-271

We develop Bayesian models to estimate cluster-level test characteristics, sensitivity, specificity, prevalence, and predictive values, based on four different sampling schemes: a single test case and three sequential test cases. The corresponding cluster-level characteristics are calculated and compared for different sample sizes, sampling schemes, individual-level sensitivities, specificities, and cut-off values. We compared posterior estimates of individual-level and cluster-level characteristics for these four sampling schemes with simulated data. Two illustrations, one for Johne’s disease in cattle and another for Salmonella in pig herds, are used to demonstrate application of the methods.  相似文献   

Variations in the acid content of rain water in the course of a single precipitation     

Michael D. Seymour  Steven A. Schubert  J. Wesley Clayton Jr.  Quintus Fernando 《Water, air, and soil pollution》1978,10(2):147-161

The major acid components in the rain water collected during five different rainfall events in July and August 1977, were found to be a strong acid, the weak acid NH _in4 ^su+ and dissolved CO₂ from the atmosphere. Variations in their concentrations were determined as a function of time in the course of each of the rainfall events. Two experimental methods were used in this investigation, a microtitrim etric method and a coulometric method, and the data were analyzed by the use of modified Gran functions. Both methods gave the same results. The most significant observation was that the strong acid concentration increased from very low values to a maximum and then decreased in the course of a single rainfall event.  相似文献   

Effects of treatment and flow on the deoxygenation rate constant     

Yung-Tse Hung  W. Wesley Eckenfelder Jr.  Tom D. Reynolds 《Water, air, and soil pollution》1978,10(2):175-185

The laboratory bench-scale experiments were conducted to investigate the effects of varying degrees of waste treatment and the flow conditions in the receiving waters on the deoxygenation rate constant (k), and ultimate biochemical oxygen demand (L), and the total O₂ utilisation of the receiving waters. Industrial wastewaters were collected from 10 major industrial plants located along the Houston Ship Channel in Texas. Two different degrees of treatment for industrial wastewaters were studied. Three different flow conditions studied were the high, the average and the low flow in the Houston Ship Channel. The k values increased for both further treatment and decreased flow in the reactor runs. The L values were higher for the average flow conditions than for the low flow conditions. The total O₂ utilization was found to increase with a decrease in the flow of the receiving waters.  相似文献   

Burrow building in seabird colonies: a soil-forming process in island ecosystems   总被引：2，自引：0，他引：2  

Wesley J. Bancroft  Mark J. Garkaklis  J. Dale Roberts 《Pedobiologia》2005,49(2):149-165

Soil modification via biopedturbation by burrow-building seabirds was examined in a Mediterranean, island ecosystem. Physical and chemical soil properties were compared between a colony of Wedge-tailed Shearwaters (Puffinus pacificus) and adjacent heath across a 14-month period. When compared to heath soil, the biopedturbated soil was 28% drier (6.04±5.40 vol%), had increased bulk density (by 29% to 1.30±0.11 g cm⁻³, 51% porosity), wetting capacity (by 83% to 0.55±0.83 molarity of ethanol droplet), hydraulic conductivity (by 266% to 398.91±252.04 mm h⁻¹), and a greater range in soil surface temperature (31.7±6.2 °C diurnally to 18.3±3.2 °C nocturnally). Soil penetration resistance was reduced by 26% at a depth of 0–100 mm (326.5±122.4 kPa) and by 55% at 500–600 mm (1116.8±465.0 kPa). Colony soil also had increased levels of nitrate (by 470%), phosphorous (118%), ammonium (102%), sulphur (69%), and potassium (34%), decreased levels of iron (by 50%) and organic carbon (61%), was more alkaline, and had a 78% greater conductivity. Shearwaters deposited guano at a rate of 234.4 kg ha⁻¹ yr⁻¹ (dry mass). Chemical analysis of guano equated this to 50.9, 5.7, 5.5, and 3.6 kg ha⁻¹ yr⁻¹ of nitrogen, potassium, sulphur, and phosphorous, respectively. Experimentally constructed burrows demonstrated that digging alone can alter physical and chemical soil factors, but that changes in the nutrient profile of colony soils are predominantly guano-driven. We argue that the physical impact of seabirds on soil should not be overlooked as a soil-forming and ecosystem-shaping factor in island ecosystems, and that biopedturbation can exert major bottom-up influences on insular plant and animal communities.  相似文献