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1.
以兰州主城区为例,运用核密度估计法,在对公园绿地空间布局特征分析的基础上,采用改进的两步移动搜索法对公园绿地供需匹配性进行评价,并探究其成因。结果表明:1)公园绿地总体分布呈现整体分散、局部集中的特征;不同类型公园绿地空间布局模式存在较大差异,综合公园呈现“均匀式”布局态势,专类公园呈现“双核心”空间格局,社区公园呈现“西密东疏”的集聚特征。2)主城区公园绿地供需匹配程度总体呈现出“北高南低、西高东低”空间分布特征;从西北—东南向剖面来看,总体呈现出“M”型分布态势;不同类型公园绿地供需比值均大致呈现出“西高东低”的共性特征,但由于各类公园绿地分布数量、面积和服务半径的差异,不同类型公园绿地与人口供需匹配程度也存在差异。3)人口分布、交通路网、公园绿地自身及周边环境是影响城市公园绿地供需匹配度空间分异的主要因素。  相似文献   
2.
对某款纯电动汽车的驱动电机参数、传动系统参数、电池组参数等进行参数匹配选型,并借助汽车仿真软件AVL Cruise(Cruise是一款在业界功能最强大、最稳定,适用性最广的整车和传动系统性能分析的仿真工具)进行动力性能仿真分析。经过仿真验证之后,该参数匹配过程正确,动力性能达到设计的要求。  相似文献   
3.
In the veterinary profession, the body condition score (BCS) plays an important role in the assessment of patients. It is a subjective, tactile method of evaluating body fat and muscle mass and is used in numerous species. Recognizing obesity (or the contrary, emaciation) is important for veterinarians treating reptiles and could be facilitated by a BCS. An existing form of body condition assessment already used is the body condition index (BCI), where the residuals from a regression of body mass on body length are calculated. Therefore, the goal of this study was to provide practitioners with a BCS system for corn snakes (Pantherophis guttatus) and to test it against the BCI. A total of 22 corn snakes (Pantherophis guttatus), stationed at the “Auffangstation für Reptilien” in Munich (reptile rescue centre, RRC), were subject of this study. Each had the following measurements taken: body weight (BW), snout–tail tip length (STL), snout–vent length (SVL) and circumference in the middle (C). Manual palpation of spine, area between vertebral spinous and transverse process, ribs and neck of each snake was performed by three veterinarians and assigned to specific scores by each examiner. A BCS (mean of examiners’ scores) was given to each snake according to manual palpation. The BCS system was chosen to be out of 5 in 0.5-point steps with 2.5 considered as ideal BCS. In the studied snakes, the BCS ranged from 1.5 to 3.5, with a median of 2.5. The median BW was 309 g (75–967 g), the median STL was 123 cm (79–153 cm), the median SVL was 104 cm (73–133 cm) and the median C was 7.5 cm (4.3–11 cm). BCS and BCI were positively correlated. A BCS includes a manual palpation of the animal and thus gives the examiner additional information to the objectively measured/calculated index.  相似文献   
4.
本文就如何保证农产品农药残留能力验证实验结果满意需要注意几个关键点进行探讨分析。要想通过板栗中毒死蜱农残的能力验证,样品前处理采用NY/T 761的方法,必须注意:提取液的过滤要用定性滤纸或脱脂棉,提取液过滤后静置时间控制在30 min~40 min之间,吸取10 mL乙腈液体要准确,净化步骤的水浴温度要严格按照方法要求,氮吹切记不要吹的太干,吹到潮乎乎为宜,SPE小柱的活化平衡要充分,上样时液面不能流干,上样后尽可能流干再洗脱,最后定容5.00 mL要准确。检测结束后,对结果进行验证很重要,可采用盲样的空白基质基质配标和空白基质基质加标画标准曲线两种办法。  相似文献   
5.
合理地进行人岗匹配,是有效实现农业企业人力资源管理职能的前提。而能岗匹配原理作 为人力资源招聘过程中的黄金法则,正逐渐成为人力资源管理研究的热点,受到越来越多学者的关 注。本文详细阐述了能岗匹配原理,剖析了能级与权级的异同之处,并尝试提出相关理论的在操作中 的操作方式。  相似文献   
6.
研究了紫甘蓝泥、酵母、面包改良剂和烤焙油对紫甘蓝吐司品质的影响。在单因素试验的基础上,以感官评分为判断标准,通过正交试验确定吐司的最佳工艺配方并对感官品质和质构特性的关系进行分析。结果表明:当紫甘蓝泥添加量9.0%,酵母添加量1.2%,面包改良剂添加量0.6%,烤焙油添加量6.0%时,研制出的紫甘蓝吐司感官品质最佳。同时,利用逐步回归分析法建立感官评分与质构特性间的最优线性回归模型:Y(感官评分)=-92.388+18.315X2(弹性)。本研究为紫甘蓝吐司的研发与生产提供理论参考。  相似文献   
7.
This study was carried out to better understand non-adoption of improved varieties of potato (Solanum tuberosum) and associated technologies by smallholder farmers in Chencha, Ethiopia. Data were collected through a survey (n = 47) and in-depth interviews (n = 20). It shows how wealth status was a factor of major importance. Most wealthy and some medium-wealthy farmers adopted improved potato varieties and many of the improved production practices; they had access to seed, associated knowledge and support, and sufficient resources that were necessary to apply the improved practices. Non-adoption was common among many medium-wealthy and most poor farmers: they lacked—next to access to the technologies and knowledge—cash, land, and labor. Results indicated the need to rethink research and intervention efforts. Next to paying attention to differences in the access to technology and the related knowledge, there is a need to consider the variation in technology needs, supporting microcredit services, and room to experiment. As a result, different combinations of improved production practices may be adopted.  相似文献   
8.
ABSTRACT

Aims: To assess the change in body condition score (BCS) during the early and late dry periods and its association with postpartum diseases and milk yield in grazing dairy cows from central Argentina.

Methods: BCS assessments during the dry period, and cow health and milk production records up to 90 days in milk (DIM), were collated for cows from 28 farms at monthly visits between 2007 and 2008. Cows were categorised into four groups; those in Group 1 (n=7,067) maintained or gained BCS during the early and late dry periods; Group 2 (n=2,615) maintained or gained BCS during the early dry period and lost BCS during the late dry period; Group 3 (n=1,989) lost BCS during the early dry period and maintained or gained BCS during the late dry period; and Group 4 (n=5,144) lost BCS during the early and late dry periods.

Results: Cows in Group 1 had reduced odds of having retained fetal membranes (RFM), metritis, and clinical mastitis up to 90 DIM than cows in Group 2 (p<0.001), but the odds of disease were similar to cows in Group 3. The odds of having RFM or clinical mastitis tended to be lower in cows in Group 1 than cows in Group 4 (p=0.08). The odds of cows being culled or dying during the first 90 DIM were lower for cows in Group 1 than for those in Groups 2, 3, and 4 (p≤0.05). Mean accumulated milk yield up to 90 DIM was higher in cows in Group 1 than Group 2 and Group 4 (p<0.001), but was similar to that of cows in Group 3 (p=0.28).

Conclusions and clinical relevance: Cows that lost BCS during the late dry period had increased odds of being diagnosed with several postpartum diseases and had decreased milk yield compared to cows that maintained or gained BCS during the entire dry period. Loss of BCS during any stage of the dry period was also associated with increased incidence of culling or death during the first 90 DIM. These results should raise awareness among dairy cattle producers of the importance of properly managing cow body condition during the dry period, especially during the late dry period.  相似文献   
9.
ObjectiveTo assess the sedative and immobilization effect of intranasal administration (INS) of midazolam (MID) without or with INS dexmedetomidine (DXM), and some physiological changes induced by the drugs. The ability of INS atipamezole to reverse the DXM component was also assessed.Study designProspective ‘blinded’ experimental study.AnimalsIn total, 15 pigeons.MethodsPigeons were sedated by INS MID alone at a dose of 5 mg kg−1 (group MID, n = 6) or in combination with INS DXM at a dose 80 μg kg−1 (group MID-DXM, n = 6). Measurements were made of heart rate (HR), respiratory rate (fR) and cloacal temperature (CT). The degree of sedation was assessed at 15 minutes prior to, immediately after, and at intervals until 100 minutes after drug administrations. Following MID-DXM, INS atipamezole (250 μg kg−1) was administered and the same indices measured 5 and 10 minutes later.ResultsMID had no effect on HR and fR, and although CT decreased, it remained within physiological range. MID-DXM caused significant falls in HR, fR and CT that persisted until the end of sedation. Atipamezole antagonized sedation and cardiorespiratory side effects of MID-DXM within 10 minutes of application. In addition, for MID compared to MID-DXM, the lowest sedation scores [10 (7–14) and 10.5 (5–14) versus 2 (1–4) and 2 (1–5)] were achieved in the 10th and 20th minute versus the 20th and 30th minute of the sedation, respectively.Conclusions and clinical relevanceMID alone, given INS had minimal side effects on vital functions but caused inadequate immobilization of pigeons for restraint in dorsal recumbency. MID-DXM caused an effective degree of immobilization from 20 to 30 minutes after administration, at which time birds tolerated postural changes without resistance. Atipamezole antagonized both side effects and sedation, but complete recovery had not occurred within 10 minutes after its application.  相似文献   
10.
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