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71.
Hamid ME Alla KM Ahmed SS El Shiekh AE Ibrahim KE 《Journal of the South African Veterinary Association》2006,77(2):90-91
We describe a rare case of a concurrent demodectic and sarcoptic mange in a 2-year-old heifer in Khartoum, Sudan. The lesions were massive lumps of granulomatous tumour-like dermatitis with thick, nodular folds mainly covering the head, neck and shoulders. Histopathological examination of the lesions revealed the presence of both Demodex bovis and Sarcoptes scabiei. The animal died regardless of the anti-parasitic treatment it received. 相似文献
72.
Ahmed Faraj Ali Al-Zankana Lisa S. Smallwood Tom Matheson David M. Harper 《水产资源保护:海洋与淡水生态系统》2021,31(10):2697-2713
- Many river rehabilitation projects have been criticized for failing to meet their goals or for being insufficiently monitored. There is, therefore, an urgent need to develop robust approaches for assessing treatment efficacy and thus guide the increasing investment in rehabilitation.
- Instream biotopes (formerly called ‘functional habitats’ or ‘mesohabitats’ by different authors) and their macroinvertebrate assemblages were used to assess the effectiveness of entire-channel hydromorphological rehabilitation of a 1.8-km stretch of a lowland stream through the town of Market Harborough, Leicestershire, UK.
- The project successfully enhanced the physical diversity, measured in the rehabilitated reach as the coefficients of variability for channel water depth and width, wet surface area, number of instream biotopes, and biotope diversity.
- The project also enhanced the biodiversity conservation value, measured as macroinvertebrate total density, total biomass, richness, diversity, Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness, EPT diversity, EPT count%, and EPT biomass%, all of which significantly increased following rehabilitation. Chironomidae count% and biomass% significantly decreased following rehabilitation. Rehabilitation was also successful in significantly increasing macroinvertebrate shredder, scraper, and filter-feeder group density.
- Changes in the macroinvertebrate community metrics in the rehabilitated reach were related significantly to changes in the percentages of cover of instream biotopes and increases in biotope diversity in the rehabilitated reach.
- Macroinvertebrate structural and functional metrics can provide quantitative data for assessing reach-level rehabilitation outcomes, if samples are collected in a pre-defined sampling protocol stratified at the instream biotope level.
- The practical implications of this work are that the design of rehabilitation projects, if based upon the recreation of biotope heterogeneity, will succeed in improving biological value and restoring the area to near naturalness if a suitable upstream source of macroinvertebrates for natural recolonization is available. The study shows that the concept of biotopes has an important role to play in river conservation management.
73.
利用随机区组试验评估了孟加拉国吉大港大学苗圃内的银合欢落叶对森林作物种白格、黄金檀和农田作物种长豇豆、鹰嘴豆和木豆的他感作用。结果表明,凋落叶诱导抑制作物的萌发和生长,该抑制作用依赖于萃取物浓度、凋落物及受体物种类型。萃取物浓度越高则他感作用越强。受体植物的生长响应随应用的凋落叶而变化。低浓度(10g·m-2)凋落叶对农田作物嫩芽生长有促进作用,而其他浓度的凋落叶则呈现明显的抑制作用,施用的凋落叶浓度越大抑制作用也越大。但是不同处理所表现出的抑制趋势并不均一,根系生长受到的影响大于嫩芽。图3表4参34。 相似文献
74.
Abdul Qayyum Siddiqui Yousef S. Al-Hafedh Ahmed H. Al-Harbi Seikh A. Ali 《Journal of the World Aquaculture Society》1997,28(1):106-112
Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m2 , grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m2 (29.6 9). and lowest at 20 prawns/m2 (17.4 g). Total yield increased from 135 g/m2 (1,350 kg/ha) at a density of 5 prawns/m2 to 261 g/m2 (2,610 kg/ha) at density 15/mz to 245 g/m2 (2,450 kg/ha) at 20/mz . Feed conversion ratios were high and ranged from 3.7 (5 prawns/m2 ) to 5.6 (20 prawns/m2 ).
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m2 for 112 d, the all-male population had the best growth performance and feed conversion ratio, followed by the mixed-sex and all-female populations. The all-male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m2 (1,590 kg/ha); the mixed-sex population had 90% marketable prawns and the yield was 135 g/mz (1,350 kg/ha); and the all-female population had 75% marketable prawns with an average yield of 108 g/m2 (1,080 kgha). 相似文献
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m
75.
Summary Explosion pulping results in strong pulp with breaking length at 100 ml CSF (Canadian standard freeness) higher than 6.5 kg and burst index approaching 4 KPa m2/g. The real advantage of eucalyptus explosion pulp over conventional CMP (chemical-mechanical pulp) and CTMP (chemical-thermo-mechanical pulp) is observed when the impregnation solution contains less than 2% NaOH along with 8% Na2SO3, and when the liquor/chips ratio equals 3. The strength of eucalyptus explosion pulp obtained by using a pretreatment solution consisting of 8% Na2SO3 and 1% NaOH is comparable with that of eucalyptus kraft pulp. The concentration of NaOH present in the pretreatment solution has a very important effect on the specific refining energy of eucalyptus explosion pulp as well as of CMP and CTMP. The explosion pulp obtained from eucalyptus pretreated with a solution containing an appropriate quantity of caustic along with Na2SO3 not only requires a minimum specific refining energy but also provides the highest strength values in comparison to that of CMP and CTMP. 相似文献
76.
P. Ahmed 《Agroforestry Systems》1991,14(1):23-37
A system of land use of alkaline wastelands of the Indo-Gangetic plain has been proposed consisting of planting Prosopis juliflora, a multi-purpose tree species, with the objectives of economic return as well as soil amelioration. Tree farming onalkaline wastelands provides not only fuel, fodder, timber and income to the rural population but also shows good effects in improving the soil characteristics. The detailed costs of such an agroforestry system on alkali soils have been worked out and the mean annual production of Prosopis juliflora on soils of different pH have been analysed. In spite of the high cost of establishing a plantation, an economic analysis of the system yields a 9.5% internal rate of return which is reasonably high for degraded lands of strongly alkali soils and also viable within the economic structure of the region. 相似文献
77.
El-Hassan A El-Sayed M Hamed AI Rhee IK Ahmed AA Zeller KP Verpoorte R 《Fitoterapia》2003,74(1-2):184-187
The aerial part of Leptadenia arborea has been shown to contain pinoresinol (1), syringaresinol (2), leucanthemitol (3) and E-ferulaldehyde (4). These known compounds are being reported for the first time from this plant. Among them, syringaresinol has shown an inhibitory effect against acetylcholinesterase. The IC(50) (the concentration of 50% enzyme inhibition) value of this compound was 200 microg/ml. 相似文献
78.
A new eudesmanolide, 1beta,9alpha-dihydroxyeudesm-3-en-5beta,6alpha,7alpha,11alphaH-12,6-olide (1), was isolated from Crataegus flava fruits. Its structure was determined by spectroscopic methods. 相似文献
79.
Zaheer Ahmed Ian J. Tetlow Duane E. Falk Qiang Liu Michael J. Emes 《Cereal Chemistry》2016,93(6):618-630
Physical properties of resistant starch (RS) were examined in a range of barley genotypes to determine the contribution of starch and seed physical characteristics to the RS component. Thirty‐three barley genotypes were studied, which varied significantly in their RS, amylose, and starch contents and grain yield. From 33 genotypes, 13 exhibiting high RS were selected for detailed physicochemical analysis of starch. In high‐RS varieties, granule size and number were unimodal, compared with normal starches from a reference genotype, which showed a bimodal distribution. Principal component analysis (PCA) showed that a higher content of granules <15 µm was positively correlated with RS and amylose content, whereas the proportion of granules 15–45 µm was negatively correlated with the RS and amylose contents. Physical fractionation of starches by centrifugation into different population sizes demonstrated that size alone is not an accurate indicator of the population of A‐type and B‐type granules within a given genotype. PCA also showed that large 15–45 µm granules were positively correlated with seed thickness and that thousand grain weight was positively correlated with seed width. High‐RS and high‐amylose genotypes showed variation in overall yield and starch content, with some genotypes showing yield comparable to the reference genotype. Analysis of amylopectin chain length distribution showed that high amylose or RS content was not associated with a higher proportion of amylopectin long chains when compared with either waxy or reference (normal) barley genotypes. This study highlights useful markers for screening barley genotypes with favorable starch characteristics. 相似文献
80.
Associate Professors S. M. Ahmed Associate Professors A. A. Abdel-Gawaad 《Journal of pest science》1975,48(10):148-150
Laboratory and field trials with two synthetic Juvenil Hormone Analogues on four Aphid species Two juvenile hormone analogues (JHA) were applied in laboratory in three different concentrations to four aphid species. Mortality-concentrations and mortality-time for the lowest concentration were plotted on logprobit paper and the slope calculated from the eye fitted lines. The results indicated the feasibility of probit analysis for concentration-mortality or time mortality responses. However in one of the aphid species i. e.Aphis gossypii, there was a lack of linearity in the relationship, this species proved to be tolerant to JHA in field trials. Both JHA supressed progeny production, the supression was found to be selective to different species. In field trials both JHA brought about appreciable reductions in the populations with the exception ofAphis gossypii. The colour ofH. arundinis was found to differ in adults insuing from treated nymphs, otherwise no remarkable morphonogenic changes were observed. 相似文献