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161.
This study was performed on Van cats to determine the volumetric, morphometric and surface area measurement values of their cervical spinal cords (SC) and vertebral canals (CC) and the ratios between their dimensions using computed tomography (CT) images. The study also aims to reveal any biometric differences in these values between the two sexes. Spinal cord and vertebral canal CT images of 16 healthy adult Van cats (8 males and 8 females) were used in the study. First, three measurement points were selected for each vertebra on their cranial, medial and caudal sections along the sagittal axis. Next, the morphometric values were obtained using the transversal images of these measurement points. The surface areas for the SC and CC were calculated using the stereological planimetry method. The Cavalieri's principle was then used to calculate the relevant anatomic structure volumes. The obtained values were then statistically analysed. SC and CC were found to be larger in males in general, while ‘SC cranial/CC cranial’ and ‘SC medial/CC medial’ dimensions and volume ratios were found to be larger in female cats on average. Bodyweight and age values were found to have a negative correlation with SC and CC ratio, but the correlation was statistically insignificant. All SC and CC surface area and volume measurements were found to be higher in male cats (p < .05). We believe the results obtained by this study will provide valuable insight into veterinary clinicians in evaluating pathological lesions in the cervical spinal cord and vertebral canal CT scans.  相似文献   
162.
Snowmelt runoff presents an enhanced threat of environmental damage. Soluble impurities which have accumulated in the snow during winter months are transported to the lower portion of the snow cover early in the melting season due to melt-freeze cycles. These contaminants are removed rapidly at very high concentrations within the first fractions of snowmelt runoff causing sudden bursts of enriched pollutants. This paper reports a physically-based mathematical model to simulate the enrichment process in a snow cover. The model is based on the liquid water flow, heat transport, and pollutant transport equations. These nonlinear partial differential equations are solved simultaneously using a six-point implicit finite difference scheme.  相似文献   
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165.
Use of Fusarium-infected seed for cereal crops results in a reduced plant density due to seedling blight. This is especially a problem in organic agriculture, for which currently no practical seed disinfection methods are available. In the present paper we investigated whether spring wheat cultivars differ in tolerance to seedling blight in vivo, whether the possible differences could be linked to cultivar differences in initial growth rates, and whether differences in weed infestation were related to differences in emergence. Seed six spring wheat cultivars (Melon, Lavett, SW Kungsjett, Epos, Pasteur, Thasos), containing three Fusarium infection levels were obtained and sown in two field experiments in 2006 and 2007 and in an outdoor pot experiment in 2007. Results indicated that the six spring wheat cultivars differed in their tolerance to seedling blight, and consequently in the percentage of emergence of their seeds. The relative levels of tolerance to seedling blight of the six cultivars were robust in the three experiments performed. No clear relationship between initial growth rates and tolerance was found. In our experiments, no early and homogenous weed pressure was present, but in the 2007 field experiment a relationship between initial seedling emergence and weed infestation after anthesis was determined. Based on the presented results we suggest that additional to resistance to Fusarium head blight (FHB), differences in tolerance to seedling blight should also be considered during selection of wheat cultivars for organic agriculture.  相似文献   
166.
This study was conducted near Hyderabad, India during 1991–1994 to quantify the effects of shoot pruning, fertilization, and root barriers around Leucaena leucocephala trees on intercropped sorghum(Sorghum bicolor) or cowpea (Vigna unguiculata) crop production under rainfed conditions. Crop plants grown with pruned trees attained higher dry matter and leaf area index than did those with unpruned trees. Two-year mean grain yields of sorghum with no root barriers were76% and 39% of pure crop yield (1553 kg ha–1)for pruned and unpruned trees, respectively. Corresponding values for cowpea were 49% and 26% of pure crop yield (1075 kgha–1). Sorghum or cowpea intercropped with trees responded to fertilizer application more strongly than did their respective pure crops, suggesting an increased need for fertilizer application in this agrisilviculture system over that currently used for pure crops. Impact of root barriers was small on either crop. Irrespective of root barriers, a high response to tree pruning suggested above ground competition for light dominated tree/crop interactions in this agrisilviculture system. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
167.
At Kafr El-Sheikh province, Egypt, out of 117 examined drafting horses, mites were detected in 20 (17.09%) horses. The recovered mites were 14 Chorioptes, four Psoroptes and two Sarcoptes whereas mites were not detected in four cases clinically showed typical mange lesions. Interestingly, neither the age nor the sex of the examined horses had a clear influence on the prevalence of the infection. Clinical signs observed in mange infested horses were in the form of irregular skin lesions, severe itching and sometimes biting of affected skin areas and decrease feed consumption. The skin lesions mainly start as erythematous area followed by developing of papules and crust formation. Skin scratches as a result of traumatized lesions usually occurred. Hair was lost on the affected parts developing irregular alopecic areas. Distribution of the lesions was varied according to the type of mite. Chorioptic mite was detected in para-anal fold, distal portion of legs and tail lesions, Psoroptic mite was detected in withers, mane, shoulder and flank lesions whereas Sarcoptic mite was isolated mainly from lesions on the head and neck. Complete clinical and parasitological cure for mite infestation were obtained within 2 weeks in both moxidectin and ivermectin treated groups with 100% recovery rate. Our results indicated that moxidectin oral gel is effective and good alternative for the treatment of chorioptic mange in horse to avoid drug resistance that may develop as a result of the intensive use of ivermectin alone for long periods.  相似文献   
168.
【目的】 采用响应面法对红枣黑斑病的拮抗细菌JK1培养基进行优化,提高其发酵产物中芽孢的浓度。为该菌应用提供数据。【方法】单因素实验确定培养基碳氮源物质,Plackett-Burman试验分析发酵培养基中对JK1发酵影响最重要的主要因素;运用最陡爬坡法对主要因素进行试验,获得主要因素的最适范围。通过响应面分析得到主要因素的最优水平。【结果】优化后的培养基组成为:麦芽浸粉 25.00 g/L、葡萄糖 0.57 g/L、大豆蛋白胨 12.5 g/L、NaCl 2.7 g/L、K2HPO4 0.25 g/L 、MgSO4 0.625 g/L。【结论】在最优发酵培养基培养下,多粘类芽孢杆菌的芽孢数提高了3.4倍,达到4.92×109CFU/mL。  相似文献   
169.
Avocado (Persea americana Mill.) is a subtropical domesticated fruit tree indigenous to Mesoamerica. It is a member of the Lauraceae family and is separated into three horticultural races (Guatemalan, Mexican, and West Indian) mainly corresponding to their ecological adaptation, botanical, and physiological traits. Main objectives of this study were to characterize the population structure, genetic diversity, and horticultural race of a total of 354 Persea spp. trees whose origin is as follow: 221 trees [P. americana, (218), P. nubigena (2) and P. krugii (1)] from the USDA-ARS-Subtropical Horticultural Research Station, Miami; 105 trees from the Fairchild Farm [P. americana (104) and P. schiedeana (1)], and 28 trees collected in Mexico [P. schiedeana (23) and P. americana (5)]. The complexity of their interracial admixture; as well as mislabeling frequency was also evaluated. Molecular marker analysis utilizing a set of 55 simple sequence repeat (SSR) markers amplified a total of 869 alleles with a mean number of alleles per locus of 15.8 and average polymorphism information content value of 0.71, indicating a high variability in the allele frequency for the collection. Significant deviations from Hardy–Weinberg equilibrium were identified after Bonferroni correction for a large number of loci (48; 87%) due to the presence of null alleles. The main source of variation for this population was found to be within individuals (66.84%), with 19.30% variation among populations, and 13.86% variation among individuals within populations. Moreover, population specific inbreeding indices (F IS ) were calculated for West Indian, Guatemalan, and Mexican [(0.1918; p value 0.0000), (0.1879; p-value 0.0000), (0.0925; p-value 0.0022)], respectively. Bayesian analysis divided the individual genotypes into groups associated with the Guatemalan, Mexican, West Indian races; interracial admixture; complex hybrids and P. schiedeana species. Also, results of the multivariate clustering method (PCA) and genetic distance analyses calculated among all possible individual combinations within the SSR diversity data agreed with Bayesian or Structure analyses results. The 55 SSRs provided complete resolution of all individuals and the estimated mislabeling error was approximately 0.28%.  相似文献   
170.
Wild forest fires are one of the greatest environmental disasters affecting forest resources. Along the coastal zone of the Mediterranean region in Turkey,forested areas are classified as first-degree, fire-sensitive areas. Every year, thousands of hectares of forests have been destroyed in Turkey. In this study, fire-access zones were determined in the Mediterranean forests of Turkey, by utilizing geographic information systems(GIS) technology. The effective reach distance of fire hoses from both sides of roads was considered in order to delineate fireaccess zones. The effective reach distance can vary based on the technical capabilities and hydraulic capacity of fire trucks(minimum and maximum pressures on water pump);terrain structures(uphill, downhill and flat); and ground slope. These factors and their influences were studied in fire sensitive forest areas located in the eastern Mediterranean city of Kahramanmaras? in Turkey. First, terrain structures on both sides of the road network and groundslope classes were determined based on GIS data layers.Then, fire access zones were delineated according to water pressure data, terrain structures, and ground-slope classes.The results indicated that 69.30 % of the forested areas were within the fire-access zones, while the rest of the forest was out of reach the fire hoses. The accessible areas were also calculated for forested areas with different firesensitivity degrees. The accessible areas were 69.59, 69.96,and 67.16 % for the forested areas that are sensitive to fires at the first, second, and third degrees, respectively. This finding has implications for the monitoring and management of fire threats in areas outside of the reach distance.The outside areas should receive extra attention and monitoring during the fire season so that fires are detected ahead of time and management has sufficient time to react.Besides, new roads should be considered for these areas in order to access more lands in a shorter amount of time.  相似文献   
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