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1.
This study presents four strategies of a novel evolutionary algorithm, multi-objective differential evolution algorithm (MDEA). The four strategies namely, MDEA1, MDEA2, MDEA3 and MDEA4 are adapted to solve the multi-objective crop planning model with multiple constraints in a farmland in the Vaalharts irrigation scheme (VIS) in South Africa. The three objectives of the model are to minimize the total irrigation water (m2) and to maximize both the total net income in South African Rand (ZAR) from farming and the total agricultural output in tons. The total area of the farm is 771,000 m2 and supplied with 704,694 m2 of irrigation water annually. Numerical results produce non-dominated solutions which converge to Pareto optimal fronts. MDEA1 and MDEA2 strategies with binomial crossover method are better for solving the crop planning problem presented than MDEA3 and MDEA4 strategies with exponential crossover method. MDEA1 found a solution with the highest total net income of ZAR 1,304,600 with the corresponding total agricultural output, total irrigation water and total planting areas of 316.26 tons, 702,000 m3 and 725,000 m2, respectively. The planting areas for the crops in the solution are 73,463 m2 for maize, 551,660 m2 for groundnut, 50,000 m2 for Lucerne and 50,000 m2 for Peacan nut. It can be concluded that MDEA is a good algorithm for solving crop planning problem especially in water deficient areas like South Africa. 相似文献
2.
The kinetics of the adsorption of Pb2+ and Cd2+ by sodium tetraborate (NTB)-modified kaolinite clay adsorbent was studied. A one-stage and two-stage optimization of equilibrium data were carried out using the Langmuir and time-dependent Langmuir models, respectively. Increasing temperature was found to increase the pseudo-second order kinetic rate constant and kinetic data for Pb2+ adsorption were found to fit well with the pseudo-second order kinetic model (PSOM) while that for Cd2+ were found to show very good fit to the modified pseudo-first order kinetic model (MPFOM). Binary solutions of Pb2+ and Cd2+ reduced the adsorption capacity of the modified adsorbent for either metal ion with increased initial sorption rate due to competition of metal ions for available adsorption sites. The use of NTB-modified kaolinite clay adsorbent reduces by approximately 72.2% and 96.3% the amount of kaolinite clay needed to adsorb Pb2+ and Cd2+ from wastewater solutions. From the two-stage batch adsorber design study, the minimum operating time to determine a specified amount of Pb2+ and Cd2+ removal was developed. The two-stage batch adsorption process predicted less than half the minimum contact time to reach equilibrium in the one-stage process for the adsorption of Pb2+ and Cd2+ by NTB-modified kaolinite clay adsorbent and requires 0.05 times the mass of the adsorbent for the single-stage batch adsorption at the same operating conditions. 相似文献
3.
More accurate spatio-temporal predictions of urban environment are needed as a basis for assessing exposures as a part of environmental studies and to inform urban protection policy and management. In this study, an information system was developed to manage the physico-chemical pollution information of Ibadan river system, Oyo State, Southwest Nigeria. The study took into account the seasonal influences of point and non-point discharges on the levels of physico-chemical parameters. The overall sensitivity of the watershed to physicochemical environmental pollution revealed that during dry season, of the 22 (100%) sample points, only 3 (13.6%) were unpolluted; 6 (27.3%) were slightly polluted; 10(45.4%) were moderately polluted; 2 (9.1%) were seriously polluted and 1 (4.5%) was exceptionally polluted. During rainy season, 3 (13.6%) were unpolluted; 7 (31.8%) were slightly polluted; 9 (40.9%) were moderately polluted; 2 (9.1%) were seriously polluted and 1 (4.5%) was exceptionally polluted. There is a considerable environmental risk associated with the present level of pollution of the Ibadan river water body on fish health and biodiversity. This research provides a basis for aquatic management and assist in policy making at national and international levels. Appropriate strategies for the control of point and non-point pollution sources, amendments and enforcement of legislation should be developed. 相似文献
4.
Tolulope Adebowale Jin Shunshun Kang Yao 《Journal of animal physiology and animal nutrition》2019,103(5):1492-1502
This study evaluated the effect of high or low digestible energy ratio of carbohydrate in a high or normal dietary energy density on performance, amino acid utilization and intestinal functions of weaned piglets. A total of 32 healthy weaners (9.60 ± 0.13 kg) were allocated to two dietary energy densities (3,400 and 3,800 kcal/kg) and two digestible energy ratio of carbohydrate to fat (9:1 and 3:1) in a 2 × 2 factorial arrangement. There were eight piglets per treatment. The feed intake of piglets was significantly increased by dietary high carbohydrate ratio (9:1) (p < 0.01); however, this did not result in improved body weight gain (p > 0.05). The piglets fed high carbohydrate energy ratio had a reduced villus height/crypt depth (VH/CD) ratio in the duodenum (p < 0.05), and dietary high energy density further decreased the VH/CD ratio in the ileum (p < 0.01). In the duodenum, the lymphocyte count was increased by dietary high energy density (p < 0.05), while dietary energy density and carbohydrate energy ratio interacted to increase lymphocyte count in the ileum (p < 0.05). The serum cholesterol, triglyceride and low‐density lipoprotein were not significantly affected (p > 0.05), but dietary energy density interacted with dietary energy ratio to increase high‐density lipoprotein concentration (p < 0.05) in piglets fed reduced carbohydrate energy ratio. Dietary high energy density reduced energy digestibility (p < 0.05), whereas high carbohydrate energy ratio increased crude protein digestibility in the piglets (p < 0.05). The intestinal sucrase, lactase activities and serum concentrations of histidine, leucine, lysine, methionine, phenylalanine, alanine, glycine, tyrosine and citrulline were higher in the piglets fed dietary increased carbohydrate energy ratio. Oxidative stress markers and volatile fatty acids concentrations were altered by the dietary treatments. It was concluded that dietary high energy density could be detrimental to piglets intestinal functions and that increased carbohydrate energy ratio could affect amino acid utilization and body weight gain in weaner pigs. 相似文献
5.
Summary Ten West African Dwarf ewes were inoculated withTrypanosoma vivax and, at varying intervals, treated subcuratively with diminazene aceturate to maintain the infection. Soon after infection all ewes and anoestrus for 40 to 96 days and 5 died by day 110 post infection. Compared to control animals, infected ewes had prolonged low levels of plasma progesterone until recovery or death. However, no gross or histological lesions were detected in the endocrine or reproductive organs. Of the survivors, the 5 that were aparasitaemic subsequently became pregnant and had normal gestations.
Tripanosomiasis Y Reproduccion: I. Effecto E Infecciones ConTrypanosoma vivax Sobre El Ciclo Estrual Y Reproduccion En La Oveja
Resumen Se inocularon 10ovejas West African Dwarf conTrypanosoma vivax y fueron tratadas periódicamente con dosis subcurativas de aceturato de diminazene, para mantener la infección. Pronto despues de la infección, todas las ovejas presentaron anestro por 40 a 96 dias y 5 murieron 110 dias después de la infección. Comparadas con controles, las ovejas infectadas presentaron niveles bajos de progesterona plasmática, hasta recuperación o muerte. Sin embargo, no se encontraron lesiones macroscópicas ni histológicas en los órganos reproductivos o endocrinos. De las sobrevivientes, las 5 que fueron aparasitémicas quedaron posteriormente preñadas y tuvieron gestaciones normales.
Trypanosome Et Reproduction. I. Effet De La Trypanosomose AT. Vivax Sur Le Cycle Oestral Et La Fecondite Chez La Brebis
Résumé Dix brebis naines de l'Afrique de l'ouest ont été inoculées avecTrypanosoma vivax et, à intervalles variés, traitées avec e l'acéturate de diminazène à dose non curative pour maintenir l'infection. Peu après celle-ci, toutes les brebis ont présenté un anoestrus de 40 à 96 jours et 5 sont mortes le 110e jour après l'infection. Comparées aux animaux témoins, les brebis infectées ont montré des taux peu élevés et polonges de progestérone du plasma jusqu'à leur guérison ou leur mot. Cependant, aucune lésion importante ou histologique n'a été décelée dans les organes de reproduction ou endocriniens. Parmi les survivantes, les 5 qui n'étaient pas parasitées sont entrées en gestation et l'ont menée normalement à terme.相似文献
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7.
Cattle cruelty and risks of meat contamination at Akinyele cattle market and slaughter slab in Oyo State,Nigeria 总被引:1,自引:1,他引:0
Olanike K. Adeyemo Isaac G. Adeyemi Emmanuel J. Awosanya 《Tropical animal health and production》2009,41(8):1715-1721
Cattle transported to the government-run cattle market and slaughter slab in Akinyele, Oyo State, Nigeria on their final voyage
are facing a disturbingly cruel, filthy and unsafe environment that is also raising the risk of contamination of meat sold
for human consumption. This report gives a picture of what the cattle have to go through before they are slaughtered. This
study also reveals cattle awaiting slaughter in abysmal health conditions, cows pulled with extreme force towards lairage
and slaughter slab. Equally disturbing is the filthy situation inside the abattoir where the risk of contamination of meat
is significant. Also, poor meat handling, transportation and sales practices subject meat to contamination leading to poor
quality and exposure of human consumers to health risk. Development of hygienic slaughter slab operations, improved transportation
system for both livestock and meat is therefore recommended; not only for Akinyele, but all abattoirs and slaughter slabs
in Nigeria. 相似文献
8.
1. Studies on the egg laying pattern of the semi-domesticated helmeted guinea fowl showed that the birds laid eggs between 06.00 and 20.00 h local time (05.00 to 19.00 h GMT). 2. More (67.9%) were laid in the evenings (15.00 to 20.00 h) than at any other period. 3. There were two distinct periods in the reproductive cycle: a breeding season which began in April and ended in September, and a resting or non-breeding period between October and March. 4. Sequence length was predominantly of 4 eggs and July was the month of peak egg production. 相似文献
9.
Comparative multivariate analysis of biometric traits of West African Dwarf and Red Sokoto goats 总被引:1,自引:1,他引:0
The population structure of 302 randomly selected West African Dwarf (WAD) and Red Sokoto (RS) goats was examined using multivariate
morphometric analyses. This was to make the case for conservation, rational management and genetic improvement of these two
most important Nigerian goat breeds. Fifteen morphometric measurements were made on each individual animal. RS goats were
superior (P < 0.05) to the WAD for the body size and skeletal proportions investigated. The phenotypic variability between the two breeds
was revealed by their mutual responses in the principal components. While four principal components were extracted for WAD
goats, three components were obtained for their RS counterparts with variation in the loading traits of each component for
each breed. The Mahalanobis distance of 72.28 indicated a high degree of spatial racial separation in morphology between the
genotypes. The Ward’s option of the cluster analysis consolidated the morphometric distinctness of the two breeds. Application
of selective breeding to genetic improvement would benefit from the detected phenotypic differentiation. Other implications
for management and conservation of the goats are highlighted. 相似文献
10.
The structure of haplotype blocks in the human genome 总被引:1,自引:0,他引:1
Gabriel SB Schaffner SF Nguyen H Moore JM Roy J Blumenstiel B Higgins J DeFelice M Lochner A Faggart M Liu-Cordero SN Rotimi C Adeyemo A Cooper R Ward R Lander ES Daly MJ Altshuler D 《Science (New York, N.Y.)》2002,296(5576):2225-2229
Haplotype-based methods offer a powerful approach to disease gene mapping, based on the association between causal mutations and the ancestral haplotypes on which they arose. As part of The SNP Consortium Allele Frequency Projects, we characterized haplotype patterns across 51 autosomal regions (spanning 13 megabases of the human genome) in samples from Africa, Europe, and Asia. We show that the human genome can be parsed objectively into haplotype blocks: sizable regions over which there is little evidence for historical recombination and within which only a few common haplotypes are observed. The boundaries of blocks and specific haplotypes they contain are highly correlated across populations. We demonstrate that such haplotype frameworks provide substantial statistical power in association studies of common genetic variation across each region. Our results provide a foundation for the construction of a haplotype map of the human genome, facilitating comprehensive genetic association studies of human disease. 相似文献