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1.
Syed Jawad Ahmad Shah Shaukat Hussain Musharaf Ahmad Farhatullah Iftikhar Ali Muhammad Ibrahim 《Journal of General Plant Pathology》2011,77(3):174-177
Fifty wheat varieties along with Jupateco-73 and Morocco were studied for the expression of leaf tip necrosis (LTN), a trait
linked with the durable rust resistance gene pair Lr34/Yr18. LTN was frequent (i.e., ≥6) in nine replications of a field experiment over 3 years in 17 genotypes, and the varieties were
considered positive for LTN. In molecular analyses of these varieties, having relative severity values up to 78 for yellow
rust and 45 for leaf rust, the 150-bp Lr34/Yr18-linked allele was consistently amplified. Expression of LTN in six of nine replications is an appropriate threshold for predicting
the presence of Lr34/Yr18 gene pair, and genotypes can be selected using this trait. 相似文献
2.
BACKGROUND: There are no data on optimal cut-off points to classify obesity among Omani Arabs. The existing cut-off points were obtained from studies of European populations. OBJECTIVE: To determine gender-specific optimal cut-off points for body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) associated with elevated prevalent cardiovascular disease (CVD) risk among Omani Arabs. DESIGN: A community-based cross-sectional study. SETTING: The survey was conducted in the city of Nizwa in Oman in 2001. SUBJECTS AND METHODS: The study contained a probabilistic random sample of 1421 adults aged > or =20 years. Prevalent CVD risk was defined as the presence of at least two of the following three risk factors: hyperglycaemia, hypertension and dyslipidaemia. Logistic regression and receiver-operating characteristic (ROC) curve analyses were used to determine optimal cut-off points for BMI, WC and WHR in relation to the area under the curve (AUC), sensitivity and specificity. RESULTS: Over 87% of Omanis had at least one CVD risk factor (38% had hyperglycaemia, 19% hypertension and 34.5% had high total cholesterol). All three indices including BMI (AUC = 0.766), WC (AUC = 0.772) and WHR (AUC = 0.767) predicted prevalent CVD risk factors equally well. The optimal cut-off points for men and women respectively were 23.2 and 26.8 kg m-2 for BMI, 80.0 and 84.5 cm for WC, and 0.91 and 0.91 for WHR. CONCLUSIONS: To identify Omani subjects of Arab ethnicity at high risk of CVD, cut-off points lower than currently recommended for BMI, WC and WHR are needed for men while higher cut-off points are suggested for women. 相似文献
3.
Introduced pests threaten many species and their control is generally beneficial for conservation, particularly on islands where complete eradication is possible. Unfortunately on ‘nearshore’ islands neighbouring source populations exist and unaided reinvasion is likely. Pest control programmes at these sites thus require a metapopulation context to adequately manage movements between source and sink populations. We investigated the ecology of introduced ship rats (Rattus rattus) on a nearshore island, and gene flow with adjacent mainland populations, in order to understand the metapopulation dynamics and relative levels of pest control required within the landscape. We sampled the entire population by trapping (n = 30), achieving eradication, and found a low rat density (3.2 ha−1) indicative of a sink population. Seed and other plant material constituted the major dietary component of rats. Despite its proximity to mainland source populations, the island population was genetically distinct with reduced allelic diversity caused by a recent reinvasion founder effect. Genetic analyses also detected recent migrants between the populations. In contrast, two mainland populations separated by a similar distance displayed complete genetic mixing. The small water gap therefore provides a sufficient barrier to lower the migration rate to the island and delay reinvasion, which nonetheless eventually happens. In order to maintain nearshore islands pest-free, conservation management will require a metapopulation approach simultaneously focusing on both island and source population pest control. 相似文献
4.
P.J. Burns PhD M.J. Jawad MS J.M. Weld MVB MRCVS W.C. Kaufman DVM D.M. Witherspoon DVM PhD E.A. Wilson MD R.H. Douglas PhD 《Journal of Equine Veterinary Science》1984,4(5):202-208
Testicular diameters and monthly blood samples were obtained from 83 stallions aged 4 to 22 years that were maintained on Central Kentucky Thoroughbred stud farms. The effects of age, season, and exposure to increased photoperiod (16 hours light/day, December 15 to April 1) on testicular diameters and plasma concentrations of FSH, LH and testosterone were studied.The results indicated that Thoroughbred stallions show distinct seasonal and age related changes in most of the reproductive parameters studied and that exposure of such stallions to increased photoperiod produced significant alterations in these changes. Although lighting stimulated testicular growth and testosterone secretion early in the breeding season such changes were short lived. Lighted stallions appeared to become refractory to the lighting program since both testicular size and plasma testosterone concentrations were significantly reduced by June. 相似文献
5.
Groups of Awasi lambs were infected with 50, 125, 250 and 500 infective larvae of Dictyocaulus filaria per kg body weight. The infection caused decreased weight gain, increased rate of respiration, and respiratory lesions. At 250 larvae/kg body weight, or more, infection was fatal to half of the lambs infected. One lamb, at the peak of infection, was producing about 5 000 larvae/g of faeces. 相似文献
6.
The effects of baffle positions with different contractions on the flow patterns and suspended solids distribution were studied. It was found that the baffle position has a significant effect on the flow patterns, suspended solids concentration and solid removal efficiency. The best location of the baffle position was found to be at a distance within 5% of the tank length from the inlet, and contraction at 67% of the tank depth. 相似文献
7.
Irrigation water reduction using System of Rice Intensification compared with conventional cultivation methods in Iraq 总被引：1，自引：1，他引：0
Khidhir Abbas Hameed Abdul-Kadhim Jawad Mosa Flayeh Abed Jaber 《Paddy and Water Environment》2011,9(1):121-127
A field study was conducted at Al-Mishkhab Rice Research Station (MRRS) during the summer season 2009 to evaluate irrigation
water use efficiency (IWUE) using Anbar 33 variety with the System of Rice Intensification compared to traditional methods.
During the growth phase, the number of leaves, stems, and roots, and the average plant height were measured every 15 days
for the two sets of methods. At maturity, the depth and length of plant roots was assessed, along with leaf area index (LAI)
of the flag leaf and plant height. The amount of irrigation water applied was measured by water meter for both methods. SRI
principles for plant age, spacing, etc., were implemented in the SRI plots. The results indicated more vigorous growth of
roots under SRI methods, reaching 13,004 cm plant−1 compared with non-SRI results of 4,722 cm plant−1. There was 42% increase in grain yield when SRI methods were used. These had water use efficiency (WUE) of 0.291 kg m−2 compared with WUE of 0.108 kg m−2 for non-SRI cultivation, almost a threefold difference. SRI practices reduced the need for irrigation water by 38.5%. 相似文献
8.
Journal of Soils and Sediments - Polyphosphate (Poly-P) is an alternative source of phosphate (P) fertilizer. However, as a condensed P, the effects of different polymerization content of poly-P on... 相似文献
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10.
Sa'eb Khresat Jawad Al‐Bakri Ragheb Al‐Tahhan 《Land Degradation \u0026amp; Development》2008,19(4):397-407
This study was carried out to evaluate the effects of deforestation on physical and chemical properties of soils under native forest in the Mediterranean region of northwestern Jordan. Land use/cover maps of 1953, 1978 and 2002 were interpreted and analysed within GIS to quantify the shift from forest to rainfed cultivation. Six sites were sampled in a non‐changed forest and in cultivated fields, three for each. Different soil properties of texture, bulk density, organic matter, total nitrogen, pH, cation exchange capacity (CEC), phosphorous and potassium were analysed. Results showed that many forests were changed into cultivated lands at a rate more than the reforestation. Subsequently, adverse effects on the studied physical and chemical properties were observed. The most affected properties were particle size distribution, bulk density of surface soil and subsoil. Organic matter and CEC decreased in cultivated soil as compared to the forest soil. Cultivated soils were found to exhibit a significantly lower status in physical and chemical soil properties as compared to forest soils. This general decline in the soil physical and chemical properties, in turn, contributed to soil erosion, reduction of soil fertility and land degradation. There is an urgent need to improve soil quality by developing sustainable land use practices to reduce the rate of soil degradation and to ensure long‐term sustainability of the farming system in the study area and in similar biophysical settings. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献