本研究以2,5-羟胆化钙醇浓度为指标,通过两项试验研究了饮水或注射VD3对仔猪血清2,5-羟胆化钙醇浓度的影响.试验选择断奶后仔猪72头(试验1和2分别36头)作为VD3处理.试验1的处理方法为:(1)对照组(仅饲料添加VD3);(2)断奶时肌内注射40000 ...本研究以2,5-羟胆化钙醇浓度为指标,通过两项试验研究了饮水或注射VD3对仔猪血清2,5-羟胆化钙醇浓度的影响.试验选择断奶后仔猪72头(试验1和2分别36头)作为VD3处理.试验1的处理方法为:(1)对照组(仅饲料添加VD3);(2)断奶时肌内注射40000 IU VD3;(3)在断奶后14 d饮水中补充5500 IU VD3/L.试验2处理方法:(1)对照组(仅饲料添加维生素);(2)断奶后28 d每升饮水添加90 IU VE和5500 IU VD3水,其中每个重复体重最轻的2头猪额外注射1000 IU VE、100000 IU VA和100000 IU VD3.结果:在两个试验中,VD3给药后血清2,5-羟维生素D3浓度发生显著变化(P<0.05).在试验1中,注射组和饮水组在给药后21和35 d血清2,5-羟维生素D3浓度显著高于对照组(P<0.05).在试验2中,无论饮水处理与否,注射组在给药3 d后血清2,5-羟维生素D3浓度达到峰值(P<0.05),而对照组和单纯饮水处理组在给药后第14和28天分别达到峰值(P<0.05).尽管无论是否进行水处理,注射组在给药后第7天血清2,5-羟维生素D3浓度均高于未注射组(P<0.05),但从给药后第21天起,单纯饮水组的血清2,5-羟维生素D3浓度均高于单纯注射组(P<0.05).结论:注射或饮水添加VD3均可提高猪血清2,5-羟维生素D3浓度.虽然单纯注射VD3对血清2,5-羟维生素D3浓度的促进作用在给药后初期大于饮水,但通过饮水持续补充VD3可以维持比单纯注射高的血清2,5-羟胆化钙醇值.展开更多
Most of the previous researches about portfolio analysis focus on short-selling. In fact, no short-selling is also important because short-selling is not allowed in stock markets of some countries. This paper gives th...Most of the previous researches about portfolio analysis focus on short-selling. In fact, no short-selling is also important because short-selling is not allowed in stock markets of some countries. This paper gives the sufficient and necessary conditions and proposes an optimal algorithm for Markowitz’s mean-variance models and Sharpe’s ratio with no short-selling. The optimal algorithm makes it easier to obtain the efficient frontiers with no short-selling.展开更多
This paper proposes the corrected likelihood ratio test （LRT） and large-dimensional trace criterion to test the independence of two large sets of multivariate variables of dimensions P1 and P2 when the dimensions P ...This paper proposes the corrected likelihood ratio test （LRT） and large-dimensional trace criterion to test the independence of two large sets of multivariate variables of dimensions P1 and P2 when the dimensions P = P1 ＋ P2 and the sample size n tend to infinity simultaneously and proportionally. Both theoretical and simulation results demonstrate that the traditional X2 approximation of the LRT performs poorly when the dimension p is large relative to the sample size n, while the corrected LRT and large-dimensional trace criterion behave well when the dimension is either small or large relative to the sample size. Moreover, the trace criterion can be used in the case of p 〉 n, while the corrected LRT is unfeasible due to the loss of definition.展开更多
文摘本研究以2,5-羟胆化钙醇浓度为指标,通过两项试验研究了饮水或注射VD3对仔猪血清2,5-羟胆化钙醇浓度的影响.试验选择断奶后仔猪72头(试验1和2分别36头)作为VD3处理.试验1的处理方法为:(1)对照组(仅饲料添加VD3);(2)断奶时肌内注射40000 IU VD3;(3)在断奶后14 d饮水中补充5500 IU VD3/L.试验2处理方法:(1)对照组(仅饲料添加维生素);(2)断奶后28 d每升饮水添加90 IU VE和5500 IU VD3水,其中每个重复体重最轻的2头猪额外注射1000 IU VE、100000 IU VA和100000 IU VD3.结果:在两个试验中,VD3给药后血清2,5-羟维生素D3浓度发生显著变化(P<0.05).在试验1中,注射组和饮水组在给药后21和35 d血清2,5-羟维生素D3浓度显著高于对照组(P<0.05).在试验2中,无论饮水处理与否,注射组在给药3 d后血清2,5-羟维生素D3浓度达到峰值(P<0.05),而对照组和单纯饮水处理组在给药后第14和28天分别达到峰值(P<0.05).尽管无论是否进行水处理,注射组在给药后第7天血清2,5-羟维生素D3浓度均高于未注射组(P<0.05),但从给药后第21天起,单纯饮水组的血清2,5-羟维生素D3浓度均高于单纯注射组(P<0.05).结论:注射或饮水添加VD3均可提高猪血清2,5-羟维生素D3浓度.虽然单纯注射VD3对血清2,5-羟维生素D3浓度的促进作用在给药后初期大于饮水,但通过饮水持续补充VD3可以维持比单纯注射高的血清2,5-羟胆化钙醇值.
基金the National Natural Science Foundation of China (Grant Nos. 10501005, 10701021)Northeast Normal University (Grant No. NENU-STC07001)
文摘Most of the previous researches about portfolio analysis focus on short-selling. In fact, no short-selling is also important because short-selling is not allowed in stock markets of some countries. This paper gives the sufficient and necessary conditions and proposes an optimal algorithm for Markowitz’s mean-variance models and Sharpe’s ratio with no short-selling. The optimal algorithm makes it easier to obtain the efficient frontiers with no short-selling.
基金supported by National Natural Science Foundation of China(Grant Nos.11101181,11171057,11171058 and 11071035)Research Fund for the Doctoral Program of Higher Education of China(Grant No.20110061120005)+1 种基金NECT-11-0616,PCSIRTthe Fundamental Research Funds for the Central Universities
文摘This paper proposes the corrected likelihood ratio test （LRT） and large-dimensional trace criterion to test the independence of two large sets of multivariate variables of dimensions P1 and P2 when the dimensions P = P1 ＋ P2 and the sample size n tend to infinity simultaneously and proportionally. Both theoretical and simulation results demonstrate that the traditional X2 approximation of the LRT performs poorly when the dimension p is large relative to the sample size n, while the corrected LRT and large-dimensional trace criterion behave well when the dimension is either small or large relative to the sample size. Moreover, the trace criterion can be used in the case of p 〉 n, while the corrected LRT is unfeasible due to the loss of definition.
