AIM:To elucidate the profiles of commensal bacteria on the ocular surfaces of patients with varying severity of dry eye(DE).METHODS:The single-center,prospective,case-control,observational study categorized all partic...AIM:To elucidate the profiles of commensal bacteria on the ocular surfaces of patients with varying severity of dry eye(DE).METHODS:The single-center,prospective,case-control,observational study categorized all participants into three distinct groups:1)control group(n=61),2)mild DE group(n=56),and 3)moderate-to-severe DE group(n=82).Schirmer’s tear secretion strips were used,and the bacterial microbiota was analyzed using 16S ribosomal ribonucleic acid gene sequencing.RESULTS:The three groups had significant differences in alpha diversity:the control group had the highest richness(Chao1,Faith’s phylogenetic diversity),the mild DE group showed the highest diversity(Shannon,Simpson),and the moderate-to-severe DE group had the lowest of the above-mentioned indices.DE severity was positively correlated with a reduction in beta diversity of the microbial community,with the moderate-to-severe DE group exhibiting the lowest beta diversity.Linear discriminant analysis effect size presented distinct dominant taxa that significantly differed between each.Furthermore,the exacerbation of DE corresponded with the enrichment of certain pathogenic bacteria,as determined by random forest analysis.CONCLUSION:As DE severity worsens,microbial community diversity tends to decrease.DE development corresponds with changes in microbial constituents,primarily characterized by reduced microbial diversity and a more homogenous species composition.展开更多
随着电力系统中新能源机组渗透率的快速提高,系统惯量水平下降将威胁系统频率稳定性,惯量的空间分布特征也将更加凸显,频率响应的分散性将不能被忽略。针对以上问题,提出一种考虑频率响应分散性及系统分区的含风电电力系统等效惯量估计...随着电力系统中新能源机组渗透率的快速提高,系统惯量水平下降将威胁系统频率稳定性,惯量的空间分布特征也将更加凸显,频率响应的分散性将不能被忽略。针对以上问题,提出一种考虑频率响应分散性及系统分区的含风电电力系统等效惯量估计方法。首先,为降低频率响应分散性对估计精度的影响,基于谱聚类算法对电力系统进行分区,并基于皮尔逊相关系数定义频率相似度指标确定区域频率的最优测量节点。其次,由于测量所得的频率变化率(rate of change of frequency, RoCoF)曲线中包含大量的振荡分量,提出一种基于摇摆方程的数值积分方法估计区域及系统全局惯量。最后,在DIgSILENT/PowerFactory中建立改进IEEE10机39节点系统以验证所提方法的有效性。仿真结果表明,该方法适用于不同场景下含风电系统的等效惯量估计。展开更多
为了提高甘露聚糖酶ManA在毕赤酵母中分泌表达的酶活,选择毕赤酵母内质网未折叠蛋白反应(Unfolded protein response,UPR)激活调控因子HAC1与5种毕赤酵母蛋白折叠相关的分子伴侣ERO1、PDI、PDI1、CPR5、BiP,通过构建pPICZA-HAC1等6种胞...为了提高甘露聚糖酶ManA在毕赤酵母中分泌表达的酶活,选择毕赤酵母内质网未折叠蛋白反应(Unfolded protein response,UPR)激活调控因子HAC1与5种毕赤酵母蛋白折叠相关的分子伴侣ERO1、PDI、PDI1、CPR5、BiP,通过构建pPICZA-HAC1等6种胞内表达重组质粒,分别电转化至分泌表达ManA的毕赤酵母重组菌中胞内共表达,并分析其重组菌摇瓶发酵时ManA表达的影响。结果发现在摇瓶发酵水平,胞内共表达HAC1、ERO1、PDI的重组菌发酵上清液中的ManA酶活力分别提高了26%、15%、20%,其重组菌发酵上清液的酶活力分别达到1 014 U/mL、925 U/mL、965 U/mL。通过对各重组菌上清液酶活力、胞内滞留酶活力、上清液蛋白浓度数据进行分析,进一步选择将HAC1、ERO1、PDI进行两基因或三基因组合,并分别在分泌表达ManA的重组菌胞内共表达,但各共表达重组菌发酵上清液的酶活力都没有进一步的提升。单独共表达HAC1或者分子伴侣ERO1、PDI可以辅助ManA的正确折叠,提高其蛋白表达。展开更多
Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when ...Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when data are incomplete.The existing grey relational models have some disadvantages in measuring the correlation between categorical data sequences.To this end,this paper introduces a new grey relational model to analyze heterogeneous data.In this study,a set of security risk factors for small reservoirs was first constructed based on theoretical analysis,and heterogeneous data of these factors were recorded as sequences.The sequences were regarded as random variables,and the information entropy and conditional entropy between sequences were measured to analyze the relational degree between risk factors.Then,a new grey relational analysis model for heterogeneous data was constructed,and a comprehensive security risk factor identification method was developed.A case study of small reservoirs in Guangxi Zhuang Autonomous Region in China shows that the model constructed in this study is applicable to security risk factor identification for small reservoirs with heterogeneous and sparse data.展开更多
AIM: To explore the distribution pattern of macular choroidal thickness(ChT) and its association with age as well as refractive status in Chinese preschoolers.METHODS: School-based, cross-sectional study. A total of 5...AIM: To explore the distribution pattern of macular choroidal thickness(ChT) and its association with age as well as refractive status in Chinese preschoolers.METHODS: School-based, cross-sectional study. A total of 550 healthy preschool children aged 3 to 6 years old from 6 kindergartens were enrolled. Comprehensive ocular examinations, including measurement of visual acuity, axial length, intraocular pressure and slit-lamp examination before cycloplegia, as well as refraction measurement and sweptsource optical coherence tomography(SS-OCT) examination after cycloplegia, were performed. The macular ChT in each sector of the ETDRS grid was measured by the builtin software of SS-OCT.RESULTS: The mean central ChT of the participants was 312±59 μm. The mean axial length and spherical equivalent refraction were 22.36±0.72 mm and 1.51±0.83 D, respectively. Axial length increased with age(P<0.001), while the spherical equivalent refraction was similar among different age groups. Similarly, no significant difference was observed in ChT in all sectors among different age groups(all P>0.05). The central ChT of 3-4, 5 and 6 years old children was 314±59 μm, 312±60 μm and 312±59 μm, respectively(P=0.920). No difference was observed in ChT in most of the sectors between genders. No statistical significant difference was observed among different refractive groups(all P>0.05), though the ChT of each sector seemed to be smaller in myopic children. Axial length and weight were the independent factors of central Ch T. Children with longer axial length(β=-21.184, P<0.001) and smaller weight(β=1.502, P=0.041) tended to have thinner choroid.CONCLUSION: In preschool children, the ChT remains relatively stable with age, while a negative association between ChT and axial length existed. This will be helpful to elucidate the characteristics of ChT during the early refractive development.展开更多
基金Supported by Shanghai Municipal Health Commission(No.201940243).
文摘AIM:To elucidate the profiles of commensal bacteria on the ocular surfaces of patients with varying severity of dry eye(DE).METHODS:The single-center,prospective,case-control,observational study categorized all participants into three distinct groups:1)control group(n=61),2)mild DE group(n=56),and 3)moderate-to-severe DE group(n=82).Schirmer’s tear secretion strips were used,and the bacterial microbiota was analyzed using 16S ribosomal ribonucleic acid gene sequencing.RESULTS:The three groups had significant differences in alpha diversity:the control group had the highest richness(Chao1,Faith’s phylogenetic diversity),the mild DE group showed the highest diversity(Shannon,Simpson),and the moderate-to-severe DE group had the lowest of the above-mentioned indices.DE severity was positively correlated with a reduction in beta diversity of the microbial community,with the moderate-to-severe DE group exhibiting the lowest beta diversity.Linear discriminant analysis effect size presented distinct dominant taxa that significantly differed between each.Furthermore,the exacerbation of DE corresponded with the enrichment of certain pathogenic bacteria,as determined by random forest analysis.CONCLUSION:As DE severity worsens,microbial community diversity tends to decrease.DE development corresponds with changes in microbial constituents,primarily characterized by reduced microbial diversity and a more homogenous species composition.
文摘随着电力系统中新能源机组渗透率的快速提高,系统惯量水平下降将威胁系统频率稳定性,惯量的空间分布特征也将更加凸显,频率响应的分散性将不能被忽略。针对以上问题,提出一种考虑频率响应分散性及系统分区的含风电电力系统等效惯量估计方法。首先,为降低频率响应分散性对估计精度的影响,基于谱聚类算法对电力系统进行分区,并基于皮尔逊相关系数定义频率相似度指标确定区域频率的最优测量节点。其次,由于测量所得的频率变化率(rate of change of frequency, RoCoF)曲线中包含大量的振荡分量,提出一种基于摇摆方程的数值积分方法估计区域及系统全局惯量。最后,在DIgSILENT/PowerFactory中建立改进IEEE10机39节点系统以验证所提方法的有效性。仿真结果表明,该方法适用于不同场景下含风电系统的等效惯量估计。
基金supported by the National Nature Science Foundation of China(Grant No.71401052)the National Social Science Foundation of China(Grant No.17BGL156)the Key Project of the National Social Science Foundation of China(Grant No.14AZD024)
文摘Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when data are incomplete.The existing grey relational models have some disadvantages in measuring the correlation between categorical data sequences.To this end,this paper introduces a new grey relational model to analyze heterogeneous data.In this study,a set of security risk factors for small reservoirs was first constructed based on theoretical analysis,and heterogeneous data of these factors were recorded as sequences.The sequences were regarded as random variables,and the information entropy and conditional entropy between sequences were measured to analyze the relational degree between risk factors.Then,a new grey relational analysis model for heterogeneous data was constructed,and a comprehensive security risk factor identification method was developed.A case study of small reservoirs in Guangxi Zhuang Autonomous Region in China shows that the model constructed in this study is applicable to security risk factor identification for small reservoirs with heterogeneous and sparse data.
基金Supported by Municipal Human Resources Development Program for Outstanding Young Talents in Medical and Health Sciences in Shanghai(No.2017YQ019)Key Discipline of Public Health-Eye health in Shanghai(No.15GWZK0601)Overseas High-end Research Team-Eye health in Shanghai(No.GWTD2015S08)
文摘AIM: To explore the distribution pattern of macular choroidal thickness(ChT) and its association with age as well as refractive status in Chinese preschoolers.METHODS: School-based, cross-sectional study. A total of 550 healthy preschool children aged 3 to 6 years old from 6 kindergartens were enrolled. Comprehensive ocular examinations, including measurement of visual acuity, axial length, intraocular pressure and slit-lamp examination before cycloplegia, as well as refraction measurement and sweptsource optical coherence tomography(SS-OCT) examination after cycloplegia, were performed. The macular ChT in each sector of the ETDRS grid was measured by the builtin software of SS-OCT.RESULTS: The mean central ChT of the participants was 312±59 μm. The mean axial length and spherical equivalent refraction were 22.36±0.72 mm and 1.51±0.83 D, respectively. Axial length increased with age(P<0.001), while the spherical equivalent refraction was similar among different age groups. Similarly, no significant difference was observed in ChT in all sectors among different age groups(all P>0.05). The central ChT of 3-4, 5 and 6 years old children was 314±59 μm, 312±60 μm and 312±59 μm, respectively(P=0.920). No difference was observed in ChT in most of the sectors between genders. No statistical significant difference was observed among different refractive groups(all P>0.05), though the ChT of each sector seemed to be smaller in myopic children. Axial length and weight were the independent factors of central Ch T. Children with longer axial length(β=-21.184, P<0.001) and smaller weight(β=1.502, P=0.041) tended to have thinner choroid.CONCLUSION: In preschool children, the ChT remains relatively stable with age, while a negative association between ChT and axial length existed. This will be helpful to elucidate the characteristics of ChT during the early refractive development.
