A double-blinded randomized controlled field trial based on parallel group design was conducted from January, 2018 to July, 2018 in Chercher Oda-Bultum Farmers Union beef Farm. The present study was conducted to evalu...A double-blinded randomized controlled field trial based on parallel group design was conducted from January, 2018 to July, 2018 in Chercher Oda-Bultum Farmers Union beef Farm. The present study was conducted to evaluate the roll of effective microbial supplementation to feed on the infection of Salmonella in the mesenteric and sub-iliac lymph nodes of beef cattle. In order to undertake the study, 130 beef cattle kept by the farm were used to establish a cohort. The study animals were randomly assigned to the treatment group (n = 100) and control group (n = 30). The feed of treatment group was mixed with EM at dose of 5× 10<sup>10</sup> cfu/day/head for 90, 100 and 115 days while that of the control group was mixed with molasses, which acts as placebo. Both the treatment and control were slaughtered and two lymph nodes were collected from each animal under strict sterile condition and processed for the isolation and identification of Salmonella using standard procedure. The occurrence of Salmonella was 70% (CI = 51% - 85%) in control group while it was 33% (CI = 24% - 43%) in treatment group. The difference in the proportion of Salmonella infection in the two group was significant (x<sup>2</sup> = 13.01;p = 0.000). The relative risk of Salmonella isolation in the control was 2.12 (1.41 - 3.20) compared to treatment group. The absolute and relative risk reduction in the treatment were 37% (CI = 17% - 57%) and 53% (CI = 29% - 69%), respectively. This preliminary study indicated that effective microbial supplementation of beef cattle feed reduced the occurrences of Salmonella in the lymph node of beef cattle, thereby potentially minimizing the economic and public health impacts of Salmonella infection. Then, it was recommended to use EM as prevention and control option in Salmonella carriage in cattle.展开更多
随着集中式电力市场规模的扩大,需要设置电力枢纽节点作为现货市场上可以进行统一交易的聚合节点,其同时也是电力金融市场发展与稳定运行的基石,对构建统一电力市场体系、完善市场功能具有十分重要的意义。枢纽节点设计的难点在于枢纽...随着集中式电力市场规模的扩大,需要设置电力枢纽节点作为现货市场上可以进行统一交易的聚合节点,其同时也是电力金融市场发展与稳定运行的基石,对构建统一电力市场体系、完善市场功能具有十分重要的意义。枢纽节点设计的难点在于枢纽节点数量的确定,需要通过合适的数量选取以保证对电力市场定价节点的准确覆盖,体现电力空间价值。针对枢纽节点数量选取这一枢纽节点设计的关键问题,提出了一种基于t-SNE(t-distributedstochasticneighbor embedding)降维和DBSCAN(density-based spatial clustering of applications with noise)分类的枢纽节点数量确定方法。首先,通过与KPCA(kernelprincipalcomponentanalysis)、UMAP(uniform manifold approximation and projection)等典型降维方法的对比实验,证明t-SNE对数据拥挤的高维节点电价集有更好的降维效果,其数据可视化效果符合通过降维使得定价节点分成尽可能独立的类的预期。其次,应用DBSCAN算法在基于密度的基础上去除异常点与偏离点并进行分类,通过交叉熵有效选取DBSCAN最佳域值,确定最优分类数。最后,通过一系列分类的内部有效性评价指标,证明了该方法的准确性与有效性,为进一步的枢纽区域划分提供合理依据。展开更多
文摘A double-blinded randomized controlled field trial based on parallel group design was conducted from January, 2018 to July, 2018 in Chercher Oda-Bultum Farmers Union beef Farm. The present study was conducted to evaluate the roll of effective microbial supplementation to feed on the infection of Salmonella in the mesenteric and sub-iliac lymph nodes of beef cattle. In order to undertake the study, 130 beef cattle kept by the farm were used to establish a cohort. The study animals were randomly assigned to the treatment group (n = 100) and control group (n = 30). The feed of treatment group was mixed with EM at dose of 5× 10<sup>10</sup> cfu/day/head for 90, 100 and 115 days while that of the control group was mixed with molasses, which acts as placebo. Both the treatment and control were slaughtered and two lymph nodes were collected from each animal under strict sterile condition and processed for the isolation and identification of Salmonella using standard procedure. The occurrence of Salmonella was 70% (CI = 51% - 85%) in control group while it was 33% (CI = 24% - 43%) in treatment group. The difference in the proportion of Salmonella infection in the two group was significant (x<sup>2</sup> = 13.01;p = 0.000). The relative risk of Salmonella isolation in the control was 2.12 (1.41 - 3.20) compared to treatment group. The absolute and relative risk reduction in the treatment were 37% (CI = 17% - 57%) and 53% (CI = 29% - 69%), respectively. This preliminary study indicated that effective microbial supplementation of beef cattle feed reduced the occurrences of Salmonella in the lymph node of beef cattle, thereby potentially minimizing the economic and public health impacts of Salmonella infection. Then, it was recommended to use EM as prevention and control option in Salmonella carriage in cattle.
文摘随着集中式电力市场规模的扩大,需要设置电力枢纽节点作为现货市场上可以进行统一交易的聚合节点,其同时也是电力金融市场发展与稳定运行的基石,对构建统一电力市场体系、完善市场功能具有十分重要的意义。枢纽节点设计的难点在于枢纽节点数量的确定,需要通过合适的数量选取以保证对电力市场定价节点的准确覆盖,体现电力空间价值。针对枢纽节点数量选取这一枢纽节点设计的关键问题,提出了一种基于t-SNE(t-distributedstochasticneighbor embedding)降维和DBSCAN(density-based spatial clustering of applications with noise)分类的枢纽节点数量确定方法。首先,通过与KPCA(kernelprincipalcomponentanalysis)、UMAP(uniform manifold approximation and projection)等典型降维方法的对比实验,证明t-SNE对数据拥挤的高维节点电价集有更好的降维效果,其数据可视化效果符合通过降维使得定价节点分成尽可能独立的类的预期。其次,应用DBSCAN算法在基于密度的基础上去除异常点与偏离点并进行分类,通过交叉熵有效选取DBSCAN最佳域值,确定最优分类数。最后,通过一系列分类的内部有效性评价指标,证明了该方法的准确性与有效性,为进一步的枢纽区域划分提供合理依据。
