[Current situation, problems and suggestions of environmental health standardization].

In this paper, the history and current situation of environmental health standardization in China are reviewed, and the experience and shortcomings in the process of environmental health standardization in China are analyzed, suggestions for the next step of environmental health standards are also put forward.

Time Regularity of Morphology of Blood Pools.

ABSTRACT: Objective To provide reference indexes and theoretical basis for age estimation of blood pools by investigating the entire drying process and monitoring the change of morphology and mass. Methods Four 15 mL blood pool samples were prepared on the clean ceramic plate. The change of morphology and mass of blood pools in a closed dark environment with a temperature of （20.0±0.5） ℃ and a humidity of 35%-45% were dynamically observed from 0 h to 60 h. Images of the blood pools were recorded by digital camera. The area of blood pools was calculated by MATLAB R2014b, the length of cracks was measured by Image J and the statistical analysis was performed by SPSS 16.0. Results By summarizing and analyzing, the drying of blood pools was divided into five stages： coagulation （0-4.5 h）, gelation （>4.5-20.0 h）, gel-solid mixing （>20.0-37.0 h）, solid （>37.0-40.0 h） and final desiccation （>40.0-45.0 h）. From 0 to 45 h, the mass of the blood pools decreased linearly with time, and the decrease was not obvious from 45.0 to 60.0 h. The standardized mass （y2） showed strong correlation with the time （x） y2=0.018 2 x+0.271 4（R2=0.967 9）. The area change rate of blood pools, the distance that the edge of blood pools moved, the average length of radical cracks had little correlation with the time that passed. Conclusion The overall morphological characteristics of blood pools show a certain regularity with the time and the standardized indexes established provide a reference for the age estimation of blood pools.

[Influence of humidex on incidence of bacillary dysentery in Hefei: a time-series study].

Objective: To investigate the effect of humidex combined with mean temperature and relative humidity on the incidence of bacillary dysentery in Hefei. Methods: Daily counts of bacillary dysentery cases and weather data in Hefei were collected from January 1, 2006 to December 31, 2013. Then, the humidex was calculated from temperature and relative humidity. A Poisson generalized linear regression combined with distributed lag non-linear model was applied to analyze the relationship between humidex and the incidence of bacillary dysentery, after adjusting for long-term and seasonal trends, day of week and other weather confounders. Stratified analyses by gender, age and address were also conducted. Results: The risk of bacillary dysentery increased with the rise of humidex. The adverse effect of high humidex (90 percentile of humidex) appeared in 2-days lag and it was the largest at 4-days lag (RR=1.063, 95%CI: 1.037-1.090). Subgroup analyses indicated that all groups were affected by high humidex at lag 2-5 days. Conclusion: High humidex could significantly increase the risk of bacillary dysentery, and the lagged effects were observed.

Impacts of ambient temperature on the burden of bacillary dysentery in urban and rural Hefei, China.

Bacillary dysentery continues to be a major health issue in developing countries and ambient temperature is a possible environmental determinant. However, evidence about the risk of bacillary dysentery attributable to ambient temperature under climate change scenarios is scarce. We examined the attributable fraction (AF) of temperature-related bacillary dysentery in urban and rural Hefei, China during 2006-2012 and projected its shifting pattern under climate change scenarios using a distributed lag non-linear model. The risk of bacillary dysentery increased with the temperature rise above a threshold (18·4 °C), and the temperature effects appeared to be acute. The proportion of bacillary dysentery attributable to hot temperatures was 18·74% (95 empirical confidence interval (eCI): 8·36-27·44%). Apparent difference of AF was observed between urban and rural areas, with AF varying from 26·87% (95% eCI 16·21-36·68%) in urban area to -1·90% (95 eCI -25·03 to 16·05%) in rural area. Under the climate change scenarios alone (1-4 °C rise), the AF from extreme hot temperatures (>31·2 °C) would rise greatly accompanied by the relatively stable AF from moderate hot temperatures (18·4-31·2 °C). If climate change proceeds, urban area may be more likely to suffer from rapidly increasing burden of disease from extreme hot temperatures in the absence of effective mitigation and adaptation strategies.

Method for measuring the dwell time of spin-polarized Rb atoms on coated pyrex glass surfaces using light shift.

We present a simple method for directly measuring the average dwell time of spin-polarized Rb atoms on coated Pyrex glass surfaces. The method relies on the light shift of the Zeeman resonances of spin-polarized Rb atoms pumped and probed by evanescent waves, and does not depend on the microscopic details of surface interactions. We use a cell whose length is adjustable between 70 and 500 microm. The inverse of the difference between the frequency shifts caused by sigma+ and sigma- pump beams depends linearly on the cell length, from which we obtain the average dwell time tau(s). For a Pyrex glass cell coated with octadecyltrichlorosilane we find that tau(s)=0.53+/-0.03 mus at a cell wall temperature of 103 degrees C. The temperature dependence of tau(s) is fitted to tau(s)=tau[mean](0) exp(E(a)/kT), yielding a preexponential factor tau[mean](0)=2.2(-1.4)(+5.1) ns and an activation energy E(a)=0.19+/-0.03 eV.

[Cloning of HAL1 gene and characterization for salt tolerance tomato].

The HAL1 gene was cloned by PCR strategy and confirmed by sequencing. Its open read frame is 879 bp, encoding a peptide of 294 amino acids (32 kD Protein). A chimaeric construct of HAL1 and Npt II (neomycin phosphotransferase II) was constructed and introduced into commercial cultivars of tomato (Zhong SU No. 5: Lycopersicon escullentum) by Agrobacterium tumefacien-mediated gene transformation. Transformants were selected for their ability to grow and root on media containing kanamycin. Transformation was confirmed by analysis of PCR, Southern blot and RT-PCR. The salt tolerance of transgenic tomato is evaluated by comparing the fresh weight, dry weight, Na+, K+ content of transgenic tomato and control tomato. It is concluded that the over-expressing of HAL1 in tomato could enhance the salt tolerance of the transgenic tomato.