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排序方式: 共有420条查询结果,搜索用时 15 毫秒
101.
提出了一种基于期望特性的变结构新型鲁棒控制器的设计方法。该方法融合了状态反馈和变结构控制的特点,所设计的系统具有响应过程的完全鲁棒性,直流伺服系统的仿真实例验证了该方法的有效性。 相似文献
102.
Fish Physiology and Biochemistry - This study aimed to examine the effects of dietary digested soybean protein (DSP) and taurine on bile acid (BA) level, lipase activity, lipid apparent... 相似文献
103.
Ming Hung Wong Yuk Sing Gilbert Chan Chaosheng Zhang Charles Wang‐Wai Ng 《Land Degradation \u0026amp; Development》2016,27(3):500-510
This study dealt with a restoration project conducted at South‐East New Territories Landfill in Hong Kong, in order to screen suitable tree and shrub species (both native and pioneer species) for revegetation. For engineered landfills, landfill gas migration and leachate contamination to the topsoil are rarely problematic, but the lack of nutrients and moisture and poor physical soil conditions may jeopardize potential woodland establishment. The growth performance of 25 woody plant species subjected to 12 different soil amelioration and seedlings planting methods was compared. The results showed that the general performance (mortality rate, apical height, crown diameter and basal diameter) of pioneer species (notably Acacia species) was much better than that of native species in all blocks of woodland mix and scrub mix. The notch planting method was effective in helping seedling roots to have better contact with soil for water uptake, which subsequently increased the survival rates of seedlings, leading to a better tree coverage. Soil ameliorations (horticultural soil with fertilizer and horse and pig manure) generally increased the seedling survival rate and improved plant growth. Tree coverage on all the plant trial blocks was mainly established by the three Acacia species. A planting distance of 1 m was recommended for woodland establishment, and such dense seedlings planting would achieve a better tree coverage under a shorter period of time (than the distance of 3 m). Difficulties in woodland establishment were discussed, and the strategies for achieving a better tree growth were recommended. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
104.
Effect of bandaging on second intention healing of wounds of the distal limb in horses 总被引:1,自引:1,他引:0
Objective To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb.
Study Design Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing. 相似文献
Study Design Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing. 相似文献
105.
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108.
Single blood samples from 106 pregnant and seven non-pregnant Karan Swiss cows and 104 pregnant and nine non-pregnant Murrah buffaloes were measured for oestrone and oestrone sulphate hormones by radioimmunoassay. Mean plasma oestrone level was below detection limit (less than 2.5 pg/ml) in non-pregnant and 1 month pregnant cows and buffaloes. In cows the mean oestrone level fluctuated narrowly between 10.25 and 26.65 pg/ml between the second and eight months of pregnancy, followed by a steep rise in the ninth and especially in the tenth month (151.24 pg/ml). In buffaloes mean oestrone concentrations were lower and fluctuated between 14.81 and 23.56 pg/ml during the second to ninth months of pregnancy, rising sharply in the tenth month to a peak of 47.37 pg/ml. Mean oestrone sulphate levels were below detection limit (less than 16 pg/ml) during non-pregnancy, first and second months of pregnancy in cows, increasing sharply thereafter to a peak of 6401.38 pg/ml in the tenth month of pregnancy. In buffaloes, low mean levels of oestrone sulphate were recorded in the non-pregnant and up to the fourth month of pregnancy with the levels rising sharply thereafter to a peak of 6559.82 pg/ml in the tenth month. The hormone levels were not significantly different in the two species (P greater than 0.01). The possibility of using oestrone sulphate measurement as a test of pregnancy confirmation has been indicated for both species. 相似文献
109.
Song Yang Shao-wei Zhai Brian S. Shepherd Fred P. Binkowski Silas S.O. Hung Wendy M. Sealey Dong‐Fang Deng 《Aquaculture Nutrition》2019,25(6):1171-1182
Two 3‐week growth trials were performed to determine the optimum feeding rate of juvenile lake sturgeon (Acipenser fulvescens) fed with a semi‐purified dry diet (protein, 440 g; lipid, 130 g/kg) at different feeding rates: 5, 10, 20, 30, and 40 g/kg body weight per day (BW/.d‐1), for 36 g‐sized fish; and 2.5, 5, 10, 20, and 30 g/kg BW/.d‐1, for 80 g sized fish. Feeding rates significantly influenced growth performances, feed conversion ratio, wholebody lipid and moisture contents, energy and protein retention, and fasted blood glucose levels (p < 0.05). The ratio of total C/total N measured in whole fish was positively correlated to the feeding rates and the lipid contents of whole fish. Suboptimal feeding significantly depressed growth performance and protein synthesis based on the measurement of RNA/DNA ratio in white muscle. Based on polynomial regression models, an optimal feeding rate to support the maximum growth, protein and energy retention was 34.5, 22 and 27.3 g/kg BW/.d‐1, respectively, for fish sized at 36–72 g; and 29.0, 16.9 and 19.9 g/kg BW/.d‐1, respectively for fish sized at 80–140 g. Results of this study will benefit future research to develop practical feeds to replace frozen live feed and feed management for lake sturgeon. 相似文献
110.
Hung Phuc Nguyen Peerapon Khaoian Takahiro Furutani Junya Nagano Haruhisa Fukada Toshiro Masumoto 《Fisheries Science》2017,83(1):99-106
The effects of alcohol extract of soybean meal on growth performance, digestibility, and pancreatic enzyme and bile acid status of yellowtail Seriola quinqueradiata were studied. Fish were fed one of the following for 8 weeks: a fish meal (FM) control diet (FMD), a defatted soybean meal diet (SBMD), an alcohol-extracted SBM diet (ExSBMD), an ExSBMD with alcohol-extract diet (ExSBM + ExtD), and an FMD with alcohol-extract diet (FM + ExtD). Growth performance was significantly inferior in fish fed with SBM, ExSBM + ExtD, and FM + ExtD compared to FMD- or ExSBMD-fed fish. Total bile acid levels, and trypsin and lipase activities in the anterior intestine were significantly lower in fish fed with SBM, ExSBM + ExtD, and FM + ExtD than in fish fed with ExSBMD and FMD, despite similar values in gallbladder or pyloric caeca. Cholecystokinin mRNA levels of the former diet-fed fish were significantly lower than those of FMD- or ExSBMD-fed fish. Lipid and protein digestibility of fish fed with SBMD, ExSBM + ExtD, and FM + ExtD was significantly reduced in comparison with that of fish fed with FMD or ExSBMD. These findings indicate that the alcohol extract of soybean meal inhibited the secretion of bile acids and pancreatic enzymes by a decrease of cholecystokinin stimulation. This inhibition seemed to be responsible for a low growth performance through impairment of the assimilation of lipid and protein. 相似文献