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51.
介绍姚拓其人及主要创作,重点分析以中国和马来西亚为背景的文学作品,探讨其艺术风格与成就。  相似文献   
52.
我国刑事辩护中的主要问题是:对律师、法官、检察官职业的性质定位不当;刑事诉讼法对辩护制度的规定前后矛盾、脱节;对律师执业的限制过多以及国家本位、权力本位观念的影响。应树立权利本位观念;确立沉默权制度、证据开示制度、律师刑事辩护豁免权制度以及程序违法的制裁制度。  相似文献   
53.
To determine the relationship between first service conception rate (FSC) and the postpartum period (PP), 6160 calvings from 2250 crossbred dual-purpose cows were analysed. The effects of breed predominance (BT: Bos taurus and BI: Bos indicus), season of service (dry, intermediate and humid), parity (1 or 2 and more), agroecological region (Sub-humid and Dry Tropical Forest) and milk production were studied. The postpartum period was grouped according to the calving–first service interval as G1 ≤ 60 days (n = 1889); G2 > 60 ≤ 90 days (n = 1436); G3 > 90 ≤ 120 days (n = 1030); and G4 > 120 days (n = 1805). Data were analysed by chi-squared test. The overall mean for FSC was 58.2% and was lower in G1 (p < 0.01). All PP showed a breed effect on FSC, with mean values of 61.6% and 53.3% for BI and BT, respectively. Season of service also affected FSC, which was significantly lower during the humid period: 51.2% versus 57.4% and 61.5% for the intermediate and dry periods (p < 0.01), respectively. Parity and environmental effects were not observed on FSC. Levels of milk yield did influence the FSC, which decreased from 66.7% and 61.0% for milk yields of < 1500 kg and between 1501 and 2000 kg to 46.0% in milk yields > 2000 kg (p < 0.01).  相似文献   
54.
The aim of this study was to examine the monthly variation of the first service conception (FSC) and oestrus frequency (OF) from 8308 artificial inseminations (AI) of 2960 crossbred dual-purpose cows on three commercial farms with improved management located in the Maracaibo Lake Basin, Venezuela. The effects of month of the year, agroecological area (from dry tropical forest to sub-humid tropical forest on the three farms), predominant breed (BT, Bos taurus; BI, Bos indicus), and season (December–April}; May–August; and September–November) were considered. Data were analysed using logistic regression (FSC) and GLM (OF) from SAS. The mean FSC was 55.4% overall and 48.7%, 57.0% and 58.3% for farms A, B and C, respectively (p < 0.01). Within the three agroecological areas (farms A, B and C), the FSC was highest during the cooler and drier months of the year (season 1), while the lowest FSC was obtained during the months of highest rainfall and humidity (season 3) (53.3% vs 37.4%; 58.5% vs 49.0% and 63.0% vs 52.3% on farms A, B, C, respectively; p < 0.01). In the three studied farms, OF was higher during the first 4 months of the year; with a diminishing trend towards the end of the year (p % 0.05). In general, BI cows had a higher FSC than BT cows, especially during the second half of the year, when environmental conditions were characterized by higher rainfall and humidity with lower wind velocity (58.8%a 55.5%b and 46.4%c in season 1, 2 and 3 respectively; a, b, c p < 0.01).  相似文献   
55.
绿地在城市生态环境中担负着环境净化的重要功能。园林绿化中通过植物配置将人与大自然很好地协调在一起,能够体现出历史文化底蕴,在营造自然氛围、装饰环境空间方面演绎绿色的乐章,根据自然生态最优化原理设计和改造城市生产、生活,给人们带来更多的生态效益。  相似文献   
56.
关门山国家森林公园发展趋势   总被引:1,自引:0,他引:1  
阐述关门山AAAA级森林公园具备的旅游开发发展优势、有利条件,指出其存在的问题与不足,并提出发展构想。  相似文献   
57.
城市燃气管网的完整性管理   总被引:1,自引:0,他引:1  
王婷  郑洪龙  宋汉成  戴联双  孙伶  张海珊 《油气储运》2012,31(3):184-187,247
不同地区城市燃气管道的建设和运营管理水平存在很大差距,在保障燃气管网安全运行方面存在诸多问题,亟需针对燃气输配管网开展完整性管理。简述了国内外燃气管道失效事故和主要诱因,梳理了相关标准和规范。提出了燃气管网完整性管理理念:综合考虑影响管网完整性的所有因素,采取一体化管理模式,达到经济合理地保证管网安全有效运行的目的。建立了燃气管网完整性管理体系框架,包括管理体系和技术体系两个层面,贯穿应用于组织完整性、数据完整性和管理过程完整性之中,并保持一定的灵活性。完整性管理技术是实施燃气管网完整性管理的核心,通过有机结合形成了6步循环管理流程,持续完善各种完整性管理技术,可以提升燃气管网的本质安全和运营效益。  相似文献   
58.
人性化生态型景观阳台已成为城市居民亲近自然的追求。依据现代设计美学原理,论述了人性化生态型景观阳台绿化和美化设计的审美形态———技术美、形式美和艺术美内涵。在此基础上,提出人性化生态型景观阳台设计美创作的方法———技术美命题设计、形式构图和语义表达、意境营造和风格表现,并结合设计实例作了分析阐述,为当今城市广泛开展的阳台绿化和美化活动提供了设计审美的依据。  相似文献   
59.
笔者从林业生态建设项目支出管理过程中存在的突出问题入手,提出了建立林业生态建设项目支出绩效评价体系的缘由和必要性,分析了存在的困难和问题,提出了解决问题的初步构想。  相似文献   
60.
Two different artificial insemination (AI) protocols were investigated to determine the effect of the time interval from the onset of estrus (as detected by a pedometer) to the AI on the conception rate in Japanese Black cows. Seventy‐three cows were divided into two groups that received AI either after the induction of synchronized ovulation (synchronized AI group; n = 26) or at the time of observed estrus (control AI group; n = 47). Each group was further divided into two subgroups, which were artificially inseminated either 0–12 h (early AI group; n = 21) or 12–24 h (late AI group; n = 52) after the onset of estrus. There was no significant difference in the conception rate between the synchronized AI and control AI groups. The AI protocol and the detection of estrus using a threshold of counted steps (as measured by a pedometer) in this study could be effective for planned reproduction management without the observation of standing estrus in Japanese Black cows.  相似文献   
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