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81.
OBJECTIVES: To measure the acute analgesic properties of extracorporeal shock wave therapy (ESWT) in horses with navicular disease using objective ground reaction forces (GRF). STUDY DESIGN: Prospective study. ANIMALS: Nine client-owned horses with unilateral forelimb lameness caused by navicular disease. METHODS: Horses were trotted at 3 m/s over a force plate to record pre-treatment GRF of the lame and contra-lateral forelimbs. After ESWT of the lame limb, applied with a radial unit to each of the frog and heel bulb areas with 1500 pulses at 4 bar and 10 Hz, GRF measurements were repeated at 15 minutes and 24-hour intervals for 7 days. From the 5 trials recorded at each time, peak vertical force (PVF) was calculated and averaged. Data were compared between limbs and over time using a 2-way repeated-measures ANOVA. RESULTS: Mean (+/-SD) PVF was significantly different between lame (day 1; 4339+/-626 N) and contra-lateral (day 1; 5236+/-515 N) limbs pre-treatment (P<.05). After ESWT treatment, this difference remained unchanged at 15 minutes and from days 1 to 7. To confirm navicular disease, palmar digital analgesia significantly reduced the lameness (lame 5144+/-430 N; contralateral 5082+/-586 N; P>.05). CONCLUSIONS: Single ESWT treatment applied in this manner does not influence lameness in horses with navicular disease. CLINICAL RELEVANCE: Although many equine regulatory commissions currently ban the use of ESWT before competition, our results suggest that such regulations may be unfounded. Further research is required to determine the long-term analgesic properties of this frequently used treatment modality in equine athletes. 相似文献
82.
OBJECTIVE: To determine the combination of ground reaction forces (GRFs) that best discriminates between lame and non-lame dogs. To compare the sensitivity of force platform gait analysis and visual observation at detecting gait abnormalities in Labradors after surgery for rupture of the cranial cruciate ligament (CCL). ANIMALS: All dogs were adult Labrador Retrievers: 17 free of orthopedic and neurologic abnormalities, 100 with unilateral CCL rupture, and 131 studied 6 months after surgery for unilateral CCL injury, 15 with observable lameness. PROCEDURE: Dogs were walked over a force platform with GRF recorded during the stance phase. Analytic properties of force platform gait analysis were calculated for several combinations of forces. The probability of visual observation detecting a gait abnormality was compared with that of force platform gait analysis. RESULTS: We determined that a combination of peak vertical force (PVF) and falling slope were optimal for discriminating sound and lame Labradors. After surgery, many dogs (75%) with no observable lameness failed to achieve GRFs consistent with sound Labradors. CONCLUSION: A force platform is an accurate method of assessing lameness in Labradors with CCL rupture and is more sensitive than visual observation. Assessing lameness with a combination of GRFs is better than using univariate GRFs. CLINICAL RELEVANCE: Therapies for stifle lameness can be accurately and objectively evaluated using 2 vertical ground reaction forces obtained from a force platform. 相似文献
83.
盐穴地下储库的天然气注采性能是衡量储气库效能的重要指标,也是影响储气库稳定性的重要因素。依据实测地层信息建立两种不同形状的储库模型,基于天然气的市场需求规律制定盐穴储气库的注采方案,进行30年的蠕变模拟运行,研究注采方案变化对盐穴体积收缩、塑性区发展及盐穴腔壁位移量的影响。结果表明:形状差异对盐穴腔体性质的影响不明显;体积收缩随着时间的延长而增大,但增大速度逐渐变缓,低压运行期是引起盐穴腔体收缩的主要阶段;紧急采气后的低压运行期会对盐穴腔体产生不利影响,建议对不同盐穴轮流紧急采气以降低单个盐穴腔体紧急采气频率,或者采用在采气结束后立刻跟进注气的方法,保证盐穴的长期有效运行。 相似文献
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85.
结合具体工作实践,分析了DTM法、方格网法、断面法、等高线法这4种土方计算方法的特点,并对结果进行比较。 相似文献
86.
为降低农村电网的投资和运行费用,在满足负荷需求及各项技术指标限制的条件下,以线路电压降和变电站最大负荷限制为控制条件,建立各种配电方式的单位供电面积年费用与线路供电半径、变电站数量、负荷密度等因素之间的函数关系,对我国农村电网3种配电方式110/35/10kV、110/20kV、110/10kV的经济性进行研究和比较。结果表明:当负荷密度低于250kW/km2时,110/10kV配电方式的单位供电面积年费用相对较低,而负荷密度高于250kW/km2时,110/20kV的配电方式则更经济;而110/35/10kV配电方式因为使用广泛且经济性与另外2种配电方式接近,仍有很高的保留价值。 相似文献
87.
In order to comprehensively consider the possibility and the severity of frequency instability risk, this paper proposes the risk evaluation model and algorithm for frequency collapse of power grid. The uncertainties in generating dispatch, network topology and component outage are considered. The calculation method for system frequency variation is depicted while considering the active power deficiency arising from random failure of generating units, and then various probabilistic risk indices for frequency collapse are defined. The presented method can provide important reference information for evaluating the frequency collapse risk of power grid. The non-sequential Monte Carlo simulation-based results of IEEE-RTS79 show the correctness of the method. 相似文献
88.
本试验旨在研究应用奶牛群体改良(dairyherdimprovement,DHI)体系对奶牛生产性能的影响。选用 150头不同年龄、胎次、泌乳阶段的健康泌乳奶牛,进行为期 8月(2009年 6月-2010年 1月)的试验。第 1月为第 1期,不进行调整;第 2~4月第 2期,进行第 1次调整;第 5~7月为第 3期,进行第 2次调整;第 8月为第 4期,为调整后的观察期。饲粮配方和饲养管理的调整结合试验期内内蒙自治区古巴盟地区气候条件及 DHI报告中的数据信息。记录产奶量,通过 DHI软件计算 305d产奶量、305d成年当量,预测最高日产奶量及其出现时间,采集的奶样测定乳脂蛋比。结果表明:应用 DHI体系能够显著提高 305d产奶量和 305d成年当量(P<0.05),显著提高最高日产奶量(P<0.05),并缩短其出现时间(P<0.05),改善乳脂蛋比。结果提示,在内蒙古自治区古巴盟地区的气候条件下,应用 DHI体系能够提高奶牛生产性能。 相似文献
89.
90.
当前气候变化导致的自然灾害增加以及国家碳达峰碳中和目标为风景园林发展带来了历史机遇,但风景园林在我国气候变化应对中的话语权仍显不足。为提升风景园林在应对气候变化中的学科地位,厘清风景园林在气候变化应对领域的责任和担当,探索风景园林气候设计的创新路径,本研究在综合分析国内外气候变化应对相关文献和政策措施的基础上,从气候变化的减缓和适应两个方面,考察了风景园林能够做出重要贡献的领域。结果显示,风景园林应该面向气候变化适应、灾害治理、碳达峰碳中和等国家需求,加强多学科的交叉融合,一方面通过气候积极性设计在城乡人居环境中固碳增汇、降低碳排放,另一方面通过景观规划设计适应气候变化,降低灾害风险,增强城乡韧性。风景园林气候设计的创新路径包括:标准化定向、空间化定量转向、生态完整性取向、多尺度面向以及教学改革创新。从以上结果可以看出,风景园林在应对气候变化中大有可为,气候设计的创新探索可推动风景园林学科范式转型和创新发展,并为应对气候变化提供中国方案。 相似文献