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SuWen Yang,1– 3,* Bing Wang,2,4,5,* Jing Li,6 Xue Zhao,7 Yan Zhu,8 Qian Sun,9 HongMei Liu,2,4,5 XiaoJun Wen1 1School of Basic Medical Sciences, Basic Medical School, Guizhou Medical University, Guiyang, 550025, People’s Republic of China; 2Engineering Research Centre of Medical Biotechnology, Guizhou Medical University, Guiyang, Guizhou, 550025, People’s Republic of China; 3People’s Hospital of Kaiyang, Guiyang, 550300, People’s Republic of China; 4Key Laboratory of Biology and Medical Engineering, Guizhou Medical University, Guiyang, Guizhou, 550025, People’s Republic of China; 5School of Biology and Engineering, Guizhou Medical University, Guiyang, Guizhou, 550025, People’s Republic of China; 6Department of Microbial Immunology, The First Affiliated Hospital of Guizhou Medical University, Guiyang, 550004, People’s Republic of China; 7Department of Clinical Laboratory, The First People’s Hospital of Guiyang, Guiyang, 550002, People’s Republic of China; 8Department of Clinical Laboratory, The Fourth People’s Hospital of Guiyang, Guiyang, 550002, People’s Republic of China; 9Department of Emergency Medicine, The First People’s Hospital of Guiyang, Guiyang, 550002, People’s Republic of China*These authors contributed equally to this workCorrespondence: XiaoJun Wen; HongMei Liu, Guizhou Medical University, Guiyang, 550025, People’s Republic of China, Email 2547285543@qq.com; hmliu@gmc.edu.cnPurpose: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common pathogens of community- and hospital-acquired infections, and its prevalence is increasing globally. Guiyang is the capital city of Guizhou Province, Southwest China; as the transport and tourism centre of Southwest China, Guizhou Province is bordered by Yunnan, Sichuan, Chongqing, and Guangxi Provinces. Although MRSA prevalence is increasing, little is known about its aspects in the area. The purpose of this study was to analyse MRSA molecular characteristics, antimicrobial resistance, and virulence genes in Guiyang.Methods: In total, 209 MRSA isolates from four hospitals (2019– 2020) were collected and analysed by antimicrobial susceptibility testing and molecular classification by the MLST, spa, and SCCmec typing methods. Isolate antibiotic resistance rates were detected by a drug susceptibility assays. PCR amplification was used to detect the virulence gene-carrying status.Results: Twenty-four STs, including 4 new STs (ST7346, ST7347, ST7348, and ST7247) and 3 new allelic mutations, were identified based on MLST. The major prevalent ST type and clone complex were ST59 (49.8%) and CC59 (62.7%), respectively. Spa type t437 (42.1%) and SCCmec IV (55.5%) were identified by spa and SCCmec typing methods as the most important types. Drug sensitivity data showed that the multidrug resistance rate was 79.0%. There were significant differences in multidrug resistance rates and virulence gene-carrying rates for seb, hla, hlb, cna and bap between ST59 and non-ST59 types.Conclusion: ST59-SCCmecIV-t437 is a major epidemic clone in Guiyang that should be monitored by local medical and health institutions. The situation differs from other adjacent or middle provinces of China, which may be due to the special geographical location of the region and the trend in antibiotic use or lifestyle. This study provides empirical evidence for local medical and health departments to prevent and control the spread of MRSA.Keywords: methicillin-resistant Staphylococcus aureus, MRSA, multilocus sequence type, MLST, Staphylococcal protein A type, SPA, Staphylococcal chromosomal cassette mec type, SCCmec, multidrug-resistant organism, virulence gene

The objective of this study was to investigate the effects of grazing on midday gerbil (Meriones meridianus) population characteristics and survival of animals of different genders. The experiment used a randomized complete block design and was conducted in Alxa Left Banner, Inner Mongolia, China, in 2002 (The agricultural reclamation plots set up in 1994). From April 2006 to October 2010, midday gerbils were live‐trapped in 3 light grazing plots, 3 overgrazed plots, and 3 grazing exclusion plots. The quantity of vegetation was investigated in the two different grazing intensity areas and grazing exclusion area to determine the relationship between gerbils and plant food availability. The results suggested that there was higher gerbil density, individual body mass, and daily body mass growth rate in the grazing exclusion sites than the other sites across the whole year. Females had higher survival in grazing exclusion areas than in other treatments, but the males’ survival showed the opposite pattern. Our results indicated that grazing negatively influenced the midday gerbil population by reducing food availability. Grazing influenced the survival rates of male midday gerbils positively, but had negative effects on females. The reason for gendered differences in survival rates of midday gerbils requires further investigation.

本文研究了北京翠湖湿地公园夏、秋季水华优势藻血红裸藻（Euglena sanguinea）从水华发生到衰亡过程的细胞密度、形态特征及其与环境因子的关系.结果发现，2016年8月下旬至9月中旬血红裸藻密度稳定增加，9月20日藻密度达到峰值5.13×106 cells/L；9月下旬至11月底藻密度显著下降；血红裸藻在衰亡过程中呈现细胞形态由大变小、由细长变为圆形，细胞颜色由深变浅，运动速率由快变慢的趋势，衰亡后形成具透明胶被孢子的休眠体；血红裸藻群落生长的主控因子为水温和pH，其适宜的环境阈值范围为水温23~27℃，pH 7.3~8.0；其受光照强度影响存在分层现象，弱光强区域藻密度相对较低；血红裸藻的衰亡过程与铵态氮浓度呈显著正相关，低浓度时加速衰亡；与总氮浓度呈负相关，衰亡后总氮浓度显著升高；受总磷浓度影响相对较小，与溶解氧浓度无显著相关关系.

The organic matter(OM) content,compositions and fractions of shallow lake sediments were studied by chemical method from in the middle and lower reaches of Yangtze River.The results showed that the OM content varied greatly from 0.98% to 11.0 %,higher in the heavily polluted sediments than those in the light polluted ones.The distributions of OM content were closely related to lake pollution levels and human activity intensity.HA content was 1.03-6.73g/kg,and FA content is higher than the HA,from 2.73 to 9.77g/kg.Humin was the main fractions of humus,varing from 5.89 to 55.57g/kg.PQ(HA/(FA+HA)) ratio varied from 23.04% to 50.56%,and the mean content of PQ was 32.72%.PQ content were higher in the heavily polluted sediments than those in the light polluted ones,which indicated that there was a higher degree of humification in heavy polluted sediments.Combination of three kinds of humus content in the form of tightly bound humus content was the highest,and content was 3.21-47.76g/kg;followed by loosely combined humus content between 0.86-6.92g/kg.The stable combined humus were the lowest,the content varied from 0.72 to 3.89 g/kg.The loose/tight ration in the sediments were also negatively correlated with OM,TP and TN,which showed that heavily polluted shallow lakes had higher humification and humus accumulation.So humus should be paid more attention to the carbon cycling and eutrophication control in lakes.

The aging of the population is increasing worldwide due to increasing longevity and declining birth rates. Japan leads the world in the pace of aging, with currently over 1 in 5 individuals aged 65 years and over. On the positive side, Japan has ranked first in terms of life expectancy at birth, especially for females. On the negative side, significant aging of the population has increased the number of older people who are bedridden, have dementia, or are in need of long-term care (LTC) or support for daily living. Thus, whether longer life expectancy is accompanied by better health measures within aging populations is becoming a great concern. Shifting the previous narrow focus on length of life, in recent years, healthy life expectancy (HALE) has been increasingly used to measure an individual’s health status according to a series of indicators, such as self-rated health (SRH), disability, and disease consequences. The primary purpose of this dissertation is to investigate Japanese HALE and to analyze the consequences of physical disability and comorbidity on HALE at the individual level in the elderly. Data from Western nations show a well-established inverse gradient between socioeconomic status (SES) and mortality or morbidity. Because the use of SES and health indicators may depend on social context, whether health-related SES variables would diminish, persist, or grow with age is disputed. Although Japan has been long heralded as an egalitarian and largely middle-class society, the trend towards greater socioeconomic equality in terms of health has been less obvious since the 1990s. This trend has coincided with a gradually increasing income inequality. Thus, the second purpose of this dissertation is to examine the SES’s impact on HALE in the Japanese elderly, with a special emphasis on direct and indirect effects interacting with gender, age, and location factors. A series of models estimating the structural causal relationships between individual SES, physical health, and HALE among the Japanese elderly will be validated. In the LTC field, there is a consensus that disability among the elderly is the primary factor driving the demand for LTC services, leading to the Long-term Care Insurance Law introduced by the Japanese government in April 2000. The third purpose of this dissertation is to explore the structural causal relationships between SES, LTC needs, physical health and HALE in elderly individuals, which would have implications for LTC management in the Japanese elderly. Results from the dissertation may also construct lessons for the evaluation of the nation’s health and the impact of health policies for other countries as well. My doctoral dissertation is organized as follows. Chapter 1 provides an introduction to five key concepts in the development of this dissertation: population aging, HALE, SES, physical health and LTC. Furthermore, I discuss the existing theories about population health status changes and theoretical hypotheses about SES effects on HALE due to the aging of the population. Using findings from the literature, an international comparison, the trend over time, as well as gender and age differences will be presented. Subsequently, I will address the rationale, objectives, methods, and hypothetical model of the dissertation. Chapter 2 presents an empirical study on “Prefectural mortality in relation to socioeconomic status and long-term care in Japan.” Prefectures in Japan were used as units of analysis and 7 indicators were obtained from multiple data sources, which were published by government organizations and public institutions for years centering on 1995, 2000, and 2005. Based on the correlation and linear regression analyses, factors that explain the mortality, LTC and SES variation demonstrated that prefectures with higher socioeconomic level and lower LTC application rates had lower mortality of male and elderly people in Japan. With respect to gender differences, prefectural SES and LTC displayed significant associations with mortality for men but not for women. Chapter 3 presents a study on “Healthy life expectancy in relation to socioeconomic status and physical health among Japanese elderly.” A questionnaire survey was conducted with all residents aged 60 years and older in 16 municipalities of Japan where we could obtain the help of public health centers in 1998. Participants were followed until June, 2000. In all, 15,254 individuals were analyzed. Data analysis was performed by survival analysis and structural equation modeling (SEM) using SPSS 19.0 and AMOS 17.0 for Windows. The data indicated that SES was the determinant of HALE; lower SES of the elderly was associated with an increase in mortality directly and with a decrease in SRH indirectly via physical health status. The significant distribution of SES, physical health and HALE were found by gender, age and location among the elderly people in 16 municipalities of Japan. Chapter 4 is a study on “Healthy life expectancy in relation to socioeconomic status, physical health and long-term care among Japanese elderly,” and aims to elucidate the effects of SES, physical disability, comorbidity, and LTC on HALE among the suburban elderly in Japan. A questionnaire survey was conducted among all residents aged 65 years and older in a suburban area of Tokyo in 2001, with two follow-up studies being conducted in 2004 and 2007. In all, 7,905 respondents were included as analysis subjects. Data analysis was performed using survival analysis and SEM. The results indicated that improvement in SES of the elderly works toward extending their life expectancy of living with good health via improving daily living capabilities and preventing the need for LTC. Significant gender differences were found in the relationship between SES and HALE among the Japanese suburban elderly. Furthermore, with increased age, declining physical health within the high SES category appeared to override the significant effects of SES on HALE for the Japanese suburban elderly. Chapter 5 summarizes the most important findings and draws conclusions as follows: (1) A SES disparity in terms of HALE was found in Japan, while SES’s impact on HALE in the elderly represented a significant direct effect; (2) In addition to the direct effects, indirect effects of SES on HALE in the elderly were transferred by physical health, and LTC levels; (3) There were significant model differences in terms of gender, age, and location of the elderly in Japan. In this section, I also elucidate the new insights that this dissertation has generated, and point out the questions that still remain as well as new questions that have originated. Finally, there are certain issues for future studies in terms of external validity and reliability. In Japan’s aging society, a rapid increase in the elderly population is inevitable. This study promote a deeper understanding and awareness of socioeconomic HALE determinants interacting with gender, age and location, which will contribute to the development of a multi-sectorial health policy to improve the overall health of the elderly people in Japan., 首都大学東京, 2013-09-30, 博士（都市科学）, 甲第424号