Demographic composition, not demographic diversity, predicts biomass and turnover across temperate and tropical forests.

The growth and survival of individual trees determine the physical structure of a forest with important consequences for forest function. However, given the diversity of tree species and forest biomes, quantifying the multitude of demographic strategies within and across forests and the way that they translate into forest structure and function remains a significant challenge. Here, we quantify the demographic rates of 1961 tree species from temperate and tropical forests and evaluate how demographic diversity (DD) and demographic composition (DC) differ across forests, and how these differences in demography relate to species richness, aboveground biomass (AGB), and carbon residence time. We find wide variation in DD and DC across forest plots, patterns that are not explained by species richness or climate variables alone. There is no evidence that DD has an effect on either AGB or carbon residence time. Rather, the DC of forests, specifically the relative abundance of large statured species, predicted both biomass and carbon residence time. Our results demonstrate the distinct DCs of globally distributed forests, reflecting biogeography, recent history, and current plot conditions. Linking the DC of forests to resilience or vulnerability to climate change, will improve the precision and accuracy of predictions of future forest composition, structure, and function.

An overview of multiple linear regression model and its application / 中华预防医学杂志

Multiple Linear Regression (MLR) is a generalization of simple linear regression and is one of the commonly used models in multivariate statistical analysis. This article introduces the MLR model from the perspective of practical application. Four parts, including basic principle, application examples, the application condition and diagnosis, and the extension of the model, are sequentially illustrated in this article. Particularly, in the last part, alternative methods of the model are introduced when the application condition of the model is not met. We sincerely hope that this article could make our audiences have a better understanding of the MLR model in order to improve the efficiency of data utilization and statistical analysis by correctly performing this model in their research.

Overview of logistic regression model analysis and application / 中华预防医学杂志

Logistic regression is a kind of multiple regression method to analyze the relationship between a binary outcome or categorical outcome and multiple influencing factors, including multiple logistic regression, conditional logistic regression, polytomous logistic regression, ordinal logistic regression and adjacent categorical logistic regression. This paper illustrates the basic principle, independent variable selection and assignment, applied condition, model evaluation and diagnosis for multiple logistic regression model. Moreover, the principle and application for polytomous logistic regression and ordinal logistic regression models were also introduced. By providing SAS codes and detailed explanations of the result for an example of obesity, readers could be able to better understand logistic regression model, and apply this method correctly to their research and daily work, so as to improve their capacity of the data analysis.

Overview of multivariate regression model analysis and application / 中华预防医学杂志

Analyses of the multivariate regression model are ued very widely in the medical research. Analytical methods of the mutivariate regression model including multiple linear regression, logistic regression, Poisson regression and Cox proportional hazard model were introduced in this article. The contents of the article covered the application conditions of regression models, analytical procedures, strategies of selecting independent variables, extended discussions of regression models and application notes. It is expected that authors could understand the principle of the mutivariate regression model, accurately use these analytical methods in their research, improve the efficiency of data utilization, and enhance the level of statistical analyses.

The burden of infectious disease and changing pattern from in 1990 and 2010, China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the burden of infectious disease of the Chinese population in 1990 and 2010 and changing pattern in the past 20 years.</p><p><b>METHODS</b>Results of the Global Burden of Disease Study 2010 (GBD 2010) were used to demonstrate the burden of infectious disease of the Chinese population in 1990 and 2010 and changing pattern from 1990 to 2010 by gender and age groups, including indicators of incidence, mortality, years of life lost due to premature mortality (YLL), years lived with disability (YLD), disability-adjusted life years (DALY), and their age-standardized rates using data of the 2010 National Census as a standard population.</p><p><b>RESULTS</b>In 1990 incidence, standardized incidence rate, mortality, standardized mortality rate, DALY, standardized DALY rate, YLL, standardized YLL rate, YLD, and standardized YLD rate of infectious disease in China were 3 067 469 200 cases, 242 669.34 cases/100 000, 824 300 cases, 72.27 cases/100 000, 58 937 700 person-years (PYRS), 3 992.85 PYRS/100 000, 46 504 100 PYRS, 2 932.99 PYRS/100 000, 12 433 600 PYRS, and 1 059.86 PYRS/100 000, respectively. All the aboved indicators were declined from 1990 to 2010, in 2010 they were 3 065 985 800 cases, 224 351.66 cases/100 000, 388 600 cases, 30.74 cases/100 000, 19 492 200 PYRS, 1 440.75 PYRS/100 000, 12 045 700 PYRS, 891.87 PYRS/100 000, 7 446 500 PYRS, and 548.89 PYRS/100 000, respectively. When 2010's indicators were compared to those in 1990, the rates of increase of incidence, incidence rate, mortality, mortality rate, DALY, DALY rate, YLL, YLL rate, YLD, and YLD rate were 56.84%, -9.85%, -33.07%, -61.54%, -27.68%, -58.42%, -32.46%, -61.17%, -16.75%, and -52.13% for 50-69 age group; for ≥ 70 age group, 57.90%, -5.86%, 7.41%, -36.12%, -5.00%, -43.51%, -5.14%, -43.59%, -4.52%, and -43.2%.</p><p><b>CONCLUSIONS</b>The burden of infectious disease of the Chinese population was declined from 1990 to 2010; however, the incidence of infectious disease was increased in ≥ 50 age groups.</p>

The application of trajectory model in epidemiological research / 中华流行病学杂志

This article introduced the application of trajectory model in epidemiological study on fat development in sixty teenagers.Results showed that fat developing trend on three trajectories-normal fat group,high fat group and very high fat group,with independently different developing trend.Trajectory model seemed a suitable model for fitting the longitudinal data with heterogeneity.

Research on The Proteome Response of Acidithiobacillus ferrooxidans to Phosphate Starvation by SELDI-Protein Chip Technologies / 生物化学与生物物理进展

A cidithiobacillus ferrooxidans is a chemolithotrophic microorganism capable of using ferrous ions and sulphides as energy sources. This microorganism has an important role in the bioleaching of minerals. During this process, the bacteria are normally subjected to several stressing conditions, such as temperature changes, lack of nutrients or pH changes, which may affect the efficiency of the bacterial action. SELDI is a recent technology that allows for high-throughput proteomics studies. The Protein Chip SELDI technology was used to generate comparative protein profiles of A c idithiobacillus ferrooxidans grown under phosphate starvation or normal condition additionally adding Fe2+ as energy resource. There were 13 significantly differential expressed protein's peaks found by using SELDI Protein Chip technologies, which made a solid foundation for further isolation these low molecular proteins by adopting technologies such as HPLC etc.

Bioleaching of Covellite By Using Pure and Mixed Culture of Acidithiobacillus ferrooxidans and Acidithiobacillus caldus / 现代生物医学进展

Covellite oxidation was evaluated with two acidophilic thiobacilli that are important in bioleaching processes.The experiments were carried out in shake flasks in the absence and presence of 4 g/L Fe2+ (as ferrous sulphate) at pH 2.0, 150 rpm and 35 ℃. The tests showed that the copper extraction by the Acidithiobacillus ferrooxidans culture was nearly the same as that by the mixed culture of Acidithiobacillus ferrooxidans and Acidithiobacillus caldus. On the other hand, additional iron clearly improved Cu leaching.