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51.
AGPT and HA tests were employed for rapid diagnosis of PPRV infection in sheep and goats in Sudan. Forty lymph nodes and spleen samples from suspected cases of PPR in both sheep and goats were examined by AGPT and HA tests for detection of PPRV antigen. Viral antigen was detected from (77.5%) of the samples tested by AGPT and (92.5%) tested by HA test. The results of both tests revealed that HA test was more sensitive than AGPT for detection of PPRV antigen (Kappa statistics 0.4366). Another advantage of the HA test over AGPT was that it can differentiate PPRV from RPV. Thus the HA test represents a quick, easy, simple, cheap and reliable confirmatory test for the diagnosis of PPR and differential diagnosis of PPRV and RPV. The HA test was carried out using chicken, goat and pig RBCs. Chicken RBCs were found to be the most sensitive for detection of PPRV antigen, followed by goat then pig RBCs. The HA time when using chicken RBCs was 20–25 minutes, using goat RBCs was 25–30 minutes and using pig RBCs was 40–45 minutes. The distribution of PPR infection in four different regions of Sudan was investigated.  相似文献   
52.
The present research was conducted to study the responses of ‘Malas–e–Saveh’ (M) and ‘Shishe–Kab’ (Sh) Iranian pomegranates to sodium chloride (NaCl) stress under greenhouse and field conditions. Treatments included waters electrical conductivity (EC = 1.5, 3, 6, 9 and 12 dS m?1 for greenhouse) and (EC = 1.05 as control, 4.61 and 7.46 dS m?1 for field studies). Interactive effects of salinity × variety indicated the highest chlorophyll and leaf potassium concentration, and the lowest leaf chloride and sodium in control under greenhouse study. Non-photochemical quenching, effective quantum yield of photochemical energy conversion in PSII reduced under the highest salinity level in field, however, basal quantum yield of non-photochemical processes in PSII increased in the highest salinity. Sodium and chloride increased with increased in salinity. Calcium, magnesium and iron significantly decreased with increased in salinity. It seems that there are differences between pomegranate cultivars and Malas-e-Saveh is more tolerant compared with Shishe Kab.  相似文献   
53.
Veterinary Research Communications - Avian polyomavirus (APV) infection, also called as budgerigar fledgling disease (BFD) causes various health problems in many psittacine species which may cause...  相似文献   
54.
Improvement of both the tensile and impact strength of the same polymeric material has always been a great challenge for the plastic industry. The study focuses on the effect of incorporation of calcium carbonate nanoparticles (0.3 wt% to 15 wt%) into three polypropylene (PP) based matrices viz. PP homopolymer, propylene-ethylene (PP-PE) copolymer and the blend of PP:PP-PE (30:70) to improve their impact behavior without hampering the tensile strength much. A loss in both the tensile and impact properties was observed in PP based nanocomposite. However, PP-PE based nanocomposites showed a significant improvement in impact strength (47 %) at 10 wt% loading with a loss of tensile strength by 22 %. To minimize this loss a blend of PP:PP-PE (30:70) was explored as a matrix. At 10 wt% loading, this matrix showed an improvement of 30 % in impact strength whereas the tensile loss was minimized to 10 %. Further, silane coupling agent which promoted good interfacial adhesion was used for best compositions. The variation of crystalline morphology of the nanocomposites with various formulations was analyzed using differential scanning calorimetry and X-ray diffraction.  相似文献   
55.
Three transgenic rice varieties namely Khazar, Neda and Nemat, all containing a cry1Ab gene, were evaluated through PCR analysis and field examinations for their resistance at natural infestation of insect pests during 2007. The results showed that all transgenic varieties produced 1.2 kb PCR product derived from application of cry1Ab gene. In field conditions, transgenic varieties exhibited high levels of resistance against natural infestation of stem borer and the damaged plants based on dead heart or white heat for them were less than 1%. Moreover, in stem-cut bioassay 100% of released larvae died within four days after infestation. These results demonstrate that expression of cry1Ab gene in the genome of transgenic varieties provided season-long protection from the natural infestation of lepidopteran insects.  相似文献   
56.
We studied the effects of moist chilling and warming on storage protein mobilization in walnut (Juglans regia L.) kernels to assess the metabolic inhibition theory, which states that dormant seeds are unable to utilize their own food reserves and that cold conditions allow germination by activating hydrolases involved in reserve mobilization. Stratifying kernels at 5 degrees C for 40 days enhanced their germination. During both cold stratification and warm incubation of kernels, storage protein mobilization occurred in cotyledons rather than axes. Kernel amino acid concentration increased during protein mobilization, with axes of warm-incubated kernels having particularly high amino acid concentrations. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) of the soluble protein fractions from both cold-stratified and warm-incubated cotyledons revealed increased band intensities of putative glutelins (19-22 and 32-35 kDa). A very high molecular weight protease was detected by gelatin SDS-PAGE that was most active at acid to neutral pHs in imbibed, cold stratified and germinated kernels suggesting the protease(s) was synthesized earlier in the mature seeds. Thus, in dormant walnut kernels there is no block to protein mobilization, and imbibition alone is sufficient to initiate proteolysis. Catalase activity was higher in warm-incubated kernels than in cold-stratified kernels, suggesting that seed aging is hastened under warm conditions and that cold stratification in walnut kernels might involve activation of cellular repair mechanisms.  相似文献   
57.
In recent decades, ambient gaseous pollution has increased due to anthropogenic activities worldwide. The studies to evaluate the adverse effects of ambient pollutants on commonly grown food crops are still limited, especially in Asian countries like Pakistan. The present study was conducted to measure the ambient pollutants in different sites of Faisalabad and their impact on growth and yield of wheat, mung bean and peas. Plants were grown in pots and placed at three sites named as control (Wire house of Government College University, Faisalabad), low pollution (LP) (Farm Area of Ayub Agricultural Research Institute) and high pollution (HP) (GT Chowk, Faisalabad) sites. Results showed that ambient ozone (O3) concentration was highest at HP site followed by LP site and was below AOT40 in control site. Ambient pollutants caused foliar injury in crops and decreased plant height, leaf area, biomass and grain yield. Pollutants caused a reduction in photosynthetic pigments, stomatal conductance and net photosynthetic rate and grain protein contents in all three crops. In conclusion, the ambient O3 level was highest at HP site, this current O3 level and other pollutants decreased the growth and yield of important food crops.  相似文献   
58.
The Ardesen area is prone to landslides because of the climate conditions, geologic, and geomorphologic characteristics of the region. As in previous years, in 2001 due to heavy rainfall there were many landslides resulting in damage and human casualties. There is still a great danger of further landslides in the region. Therefore, it is vitally important to prepare a landslide susceptibility map of the region. In this study, the analytical hierarchy process (AHP), the statistical index (Wi), and weighting factor (Wf) methods were used to produce and later compare three susceptibility maps. For this purpose, thematic layers including landslide inventory, lithology-weathering, slope, aspect, land cover, distance to stream, drainage density, and distance to road were used. In this study area, 98% of landslides occurred in highly or completely weathered units. Lithology-weathering, land cover, and slope data layers were found to be important factors in the study area. To confirm the practicality of the three susceptibility maps were compared with a landslide activity map containing 16 active landslide zones. The outcome was that the active landslide zones do not completely fit into the high and very high susceptibility classes. But 81.3% of these landslide zones fall into the high and very high susceptibility zones of the AHP method while this is 62.5% in the case of Wi method, and 68.8% with the Wf method. In spite of the results obtained in this study, the development of a susceptibility map is usually determined by the needs and available resources. The results showed that the AHP method gave a more realistic picture of the actual distribution of landslide susceptibility, than the Wi and Wf methods.  相似文献   
59.
以塔里木盆地周边地区多种沙尘源地为研究区,通过塔中、肖塘、若羌、策勒四个风沙观测场获取的沙尘暴过程中贴地层风向、风速数据以及风蚀传感器实测的撞击颗粒数等数据计算出各地起沙临界摩擦速度,利用Gillette经典的垂直沙尘通量及Lettau水平沙尘通量公式对若羌、策勒、塔中、肖塘沙尘通量进行了估算,并通过各层实测的梯度风速作为背景值界定出塔里木盆地多种沙源类型沙通量变化比对特征,结果表明:垂直沙尘通量F量级为10-8kg/(m2.s),水平沙尘通量Q量级为10-4 kg/(m.s);风速相同情况下,F若羌最大,策勒次之,塔中、肖塘较小;Q若羌值最大,策勒次之,塔中第三,肖塘最小。垂直沙通量F与风速都表现出较好的线性相关,风速递增,垂直沙通量递增;风速递减,垂直沙通量递减。在风速递增幅度相同条件下,若羌Q值递增幅度最大,策勒次之,塔中、肖塘基本相同。  相似文献   
60.
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