Occupational Safety Culture Index (OSCI)——measuring the community and employees awareness,attitude and knowledge towards workplace safety and health in Hong Kong SAR

Promoting occupational safety and health in Hong Kong,Special Administrative Region of China is an important and ongoing mission. As the major organization with statutory responsibilities,the Occupational Safety and Health Council understand the importance to strengthen and cultivate our safety culture. It is widely believed that numbers of occupational related diseases and injuries could be prevented with the improvement of the awareness and attitudes of the employees and the public. Therefore,a comprehensive and in-depth study to monitor the occupational health and safety level and status of the community and working population is needed. Objectives: Our Council has developed the Occupational Safety Culture Index ( OSCI) to measure the current level of community and workplace safety and health awareness,knowledge and attitude. Benchmarking measures of the key safety performance indicators are to be derived thereof. Methods: A territory-wide random telephone survey was conducted to assess the community and employees'awareness,attitude and knowledge in 2008. A structured questionnaire was designed with the content validity and reliability assessed before the survey administration. A series of quality control approaches were also applied to assure the quality of the fieldwork and the reliability of the data. Results: 1,531 eligible participants'data were collected and computed into 2 types of composite indices,Occupational Safety Culture Index ( Community) ( OSCIC) and Occupational Safety Culture Index (Workplace) (OSCIW) . With the maximum score of index at 100,the overall score of OSCIC is 66. 9 and the OSCIW is 61. 3 in Hong Kong. Achievements: OSCI served as an effective management tool to measure the safety culture in Hong Kong. With a representative sample and high quality study control and validated assessment approaches,the OSCI and the sub-indices are reliable indicators to assess the effectiveness of safety culture enhancement strategy and the OSH intervention measures.

Symptoms, Pathologies, Accidents and Expectations, Regarding the Occupational Doctor and Safety Technician, in a Representative Sample of Portuguese Tattoo Artists

Introduction/Objectives: As Tattoo is being more accepted, more professionals dedicate to it. A study was designed with the aim of analysing the perception of Tattoo Artists regarding their Occupational Health/Safety team (opinion about the support provided);as to find out what type accidents, symptoms and occupational diseases they have, in order to provide a better service. Methods: This is a mixed exploratory study, containing a quantitative observational (analytical, cross-sectional) and a qualitative component (Case Study). For the statistical analysis, predominantly non-parametric tests were used. The project was approved by the Ethics Committee and informed consent was obtained. Results: In terms of symptomatology/illnesses, musculoskeletal pathology is the most reported. In terms of accidents, cuts stand out. Several statistically significant relationships were found between the variables analysed. Discussion/Conclusions: The Occupational Health and Security services are considered insufficient by most of the Tattoo artists. It would be desirable that the Occupational Doctor has concrete knowledge regarding Tattooing, in particular semiology/pathology;makes recommendations in pharmacology and/or indicates which exams could be useful. In relation to the Safety Technician, it would be desirable also to have specific knowledge about the sector, making plausible suggestions for improvement.

Longwall mining,shale gas production,and underground miner safety and health

This paper presents the results of a unique study conducted by the National Institute for Occupational Safety and Health(NIOSH)from 2016 to 2019 to evaluate the effects of longwall-induced subsurface deformations on shale gas well casing integrity and underground miner safety and health.At both deep-cover and shallow-cover instrumentation sites,surface subsidence measurements,subsurface inplace inclinometer measurements,and underground pillar pressure measurements were conducted as longwall panels were mined.Comparisons of the deep-cover and shallow-cover test site results with those from a similar study under medium cover reveal an interesting longwall-induced response scenario.Under shallow and medium covers,measured horizontal displacements within the abutment pillar are one order of magnitude higher than those measured under deep cover.On the other hand,measured vertical compressions under deep cover are one order of magnitude higher than those under shallow and medium covers.However,FLAC3 Dsimulations of the casings indicate that,in all three cases,the P-110 production casings remain intact under longwall-induced deformations and compressions,which has serious implications for future mine design in areas where shale gas wells have been drilled ahead of mining.

Assessing the reproductive health of men with occupational exposures

The earliest report linking environmental （occupational） exposure to adverse human male reproductive effects dates back to1775 when an English physician, Percival Pott, reported a high incidence of scrotal cancer in chimney sweeps. This observation led to safety regulations in the form of bathing requirements for these workers. The fact that male-mediated reproductive harm in humans may be a result of toxicant exposures did not become firmly established until relatively recently, when Lancranjan studied lead-exposed workers in Romania in 1975, and later in 1977, when Whorton examined the effects of dibromochloropropane （DBCP） on male workers in California. Since these discoveries, several additional human reproductive toxicants have been identified through the convergence of laboratory and observational findings. Many research gaps remain, as the pool of potential human exposures with undetermined effects on male reproduction is vast. This review provides an overview of methods used to study the effects of exposures on male reproduction and their reproductive health, with a primary emphasis on the implementation and interpretation of human studies. Emphasis will be on occupational exposures, although much of the information is also useful in assessing environmental studies, occupational exposures are usually much higher and better defined.

OSH star enterprise pilot scheme——a partnership approach to improve the safety performance of construction industry in Hong Kong SAR

Background: The Occupational Safety and Health Council(OSHC) is committed to improve the safety performance of the high risk construction industry.In the past three years,about 40% of the fatal accidents in the construction industry were related to Renovation,Maintenance,Alteration and Addition(RMAA).Due to the poor safety record,some of the RMAA contractors have difficulty in obtaining the Employees' Compensation Insurance(ECI) cover in the market,or if they could obtain the ECI,the premium rate would be exceedingly high.In view of this,the OSHC,the Labour Department jointly launched"OSH Star Enterprise-Pilot Scheme on Safety Accreditation for the RMAA Industry",which prompts the industry to take practicable safety measures to improve the safety of working environment and reduce occupational injuries.The program also helps the stakeholders and insurers to identify safety-conscious contractors and thereby provide them with a favourable premium rate under the Employees' Compensation Insurance Residual Scheme(ECIRS).Objectives: The OSHC launches the Pilot Scheme to improve the safety performance of the RMAA industry through providing safety training,subsidizing enterprise to purchase safety equipment and providing safety audit.We also use financial incentive to encourage RMAA enterprises to join the Pilot Scheme-for those who are accredited as "OSH Star Enterprise"could receive a premium discount from the ERIRS when obtaining the ECI.The scheme also differentiates those safety-conscious and law-abiding enterprises from the poor performers,which helps the industry and public identifying the RMAA contractors who pay attention to work safety.Methods: The Pilot Scheme targets RMAA enterprises that employ less than 50 employees in Hong Kong.A three-pronged approach is used to improve the safety performance of the RMAA industry: the Pilot Scheme provides(1) financial support for the RMAA contractors to buy a transportable temporary anchor device and full body safety harness and its anchor system;(2) safety training on RMAA work safety and safety & health supervisor course;and(3) safety audit.Results: Enterprises that successfully pass the safety audit and satisfied the Scheme requirements will be accredited as"OSH Star Enterprise",which will be valid for two years.These enterprises can also be upgraded to"OSH Gold Star Enterprise"based on their continuous improvement in safety performance.OSHC will set up a register of OSH-accredited enterprises in RMAA works for reference of the public to facilitate their choosing of accredited contractors.The Employees' Compensation Insurance Residual Scheme Bureau will provide privileged premium rate for enterprises with OSH accreditation."OSH Star Enterprise"could enjoy 40% discounts when joining their insurance scheme.For example,a skilled worker's annual premium can be reduced by about HK $ 36,000.While,the "OSH Gold Star Enterprise"could enjoy 50% discounts when joining their insurance scheme,which means a skilled worker's annual premium can be reduced up to HK $ 45,000.Achievements: This Pilot Scheme offers practical assistance as well as attractive financial incentives for the RMAA industry to improve their safety performance.The Employees'Compensation Insurance Residual Scheme provides premium discounts for enterprises that have a good safety record.It provides incentive for RMAA contractors to actively participate in the Pilot Scheme.The Scheme demonstrates that by providing a safe working environment and appropriate personal protective equipment to workers,the enterprise not only helps to reduce the accident rate of the industry but also receive an economic return.The Pilot Scheme bridges stakeholders of RMAA industry,the government and the insurance industry creating an "all-win"situation.This partnership approach to prevent injuries and accidents in the construction industry could be an effective model for other industries.

Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China

Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(<10%)between the whole plant community sampling(AP_BW)predicted NPP and the four simplified selective sampling methods,and no significant difference between the predictions of AT_BW and AP_BW except the Shennongjia site.The findings in this study highlights the critical importance of computational strategies for community-level parameterization in ecosystem process modelling,and will support the choice of parameterization methods.

Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

Control of dust in underground coal mines is critical for mitigating both safety and health hazards.For decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal mines.Recent studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator positions.While detailed dust characterization was not a focus of such studies,this is a growing area of interest.Using preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size distribution.For this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive X-ray.Results indicate that dust composition was not appreciably affected by either scrubber or the CAC.However,the wet scrubber and CAC appeared to decrease the overall particle size distribution.Such an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return air.Aside from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

Elucidating regulatory processes of intense physical activity by multi-omics analysis

Background:Physiological and biochemical processes across tissues of the body are regulated in response to the high demands of intense physical activity in several occupations,such as firefighting,law enforcement,military,and sports.A better understanding of such processes can ultimately help improve human performance and prevent illnesses in the work environment.Methods:To study regulatory processes in intense physical activity simulating real-life conditions,we performed a multi-omics analysis of 3 biofluids(blood plasma,urine,and saliva)collected from 11 wildland firefighters before and after a 45 min,intense exercise regimen.Omics profiles post-vs.pre-exercise were compared by Student’s t-test followed by pathway analysis and comparison between the different omics modalities.Results:Our multi-omics analysis identified and quantified 3835 proteins,730 lipids and 182 metabolites combining the 3 different types of samples.The blood plasma analysis revealed signatures of tissue damage and acute repair response accompanied by enhanced carbon metabolism to meet energy demands.The urine analysis showed a strong,concomitant regulation of 6 out of 8 identified proteins from the renin-angiotensin system supporting increased excretion of catabolites,reabsorption of nutrients and maintenance of fluid balance.In saliva,we observed a decrease in 3 pro-inflammatory cytokines and an increase in 8 antimicrobial peptides.A systematic literature review identified 6 papers that support an altered susceptibility to respiratory infection.Conclusions:This study shows simultaneous regulatory signatures in biofluids indicative of homeostatic maintenance during intense physical activity with possible effects on increased infection susceptibility,suggesting that caution against respiratory diseases could benefit workers on highly physical demanding jobs.

Experimental study on the acoustic roughness spectrum of high-speed railway rails

Purpose–This study aims to investigate the acoustic roughness of rails on China’s high-speed railways,with a focus on short-wavelength irregularities(less than 80 cm),which are known to significantly contribute to noise.The goal is to develop a specific acoustic roughness spectrum tailored for China’s high-speed railway system,as no such spectrum currently exists.Design/methodology/approach–A long-term tracking study was conducted on major railway lines in China,monitoring rail roughness throughout the initial operational period and the rails’service life.Data preprocessing techniques such as peak removal and curvature correction were applied for acoustic adjustments.A spatial-wavelength domain transformation was performed,providing the distribution patterns and statistical characteristics of acoustic roughness on China’s high-speed rails.Based on these analyses,a model for constructing the acoustic roughness spectrum was developed.Findings–The study found that the acoustic roughness of China’s high-speed railway rails follows aχ2 distribution with six degrees of freedom.For wavelengths greater than 8 cm,the acoustic roughness spectrum remains below the ISO specified limits.In the wavelength range of 3.2 cm to 6.3 cm,the roughness is comparable to or within the limits specified by ISO 3095:2005 and ISO 3095:2013.However,for wavelengths shorter than 2.5 cm,the roughness exceeds ISO limits.Originality/value–This research fills the gap in the lack of a specific acoustic roughness spectrum for China’s high-speed railways.By establishing a tailored spectrum based on long-term data analysis,the findings provide valuable insights for noise control and rail maintenance in the context of China’s high-speed rail system.

Predicting the Risk of Arterial Stiffness in Coal Miners Based on Different Machine Learning Models

Coal is one of the world’s main energy resources,accounting for approximately 68%of China’s current total power generation.However,several studies have demonstrated that dust,exhaust fumes,and other harmful factors in coal mines increase the risk of cardiovascular disease(CVD)among miners^([1]).Arterial stiffness(AS)is an independent risk factor of CVD,and epidemiological studies have shown that AS plays a vital role in assessing the risk of CVD^([2]).

镉应答新基因TEF-1δ的生物学功能研究

目的 探讨镉应答新基因TEF 1δ在细胞转化和致癌过程中的重要作用。方法 应用细胞转染、WesternBlot以及细胞转化等技术与方法 ,对克隆化基因TEF 1δ的生物学功能进行研究。结果 TEF 1δcDNA以pcDNA 3 1 V5 His TOPO为表达载体所转染的CHO细胞和猴肾COS1细胞均可表达相对分子质量为 3 10 0 0的TEF 1δ编码蛋白质 ,而非转染和单纯载体转染的对照细胞则无此蛋白质表达。进一步研究表明 ,TEF 1δcDNA转染NIH3T3细胞可导致TEF 1δ蛋白质超额表达 ,并与细胞转化密切相关。结论 镉的细胞转化和致癌作用至少部分因TEF 1δ基因的高表达所致。TEF 1δ可能是一个新发现的镉应答原癌基因。

TEF-1δ基因真核细胞稳定表达系统的构建与鉴定

目的 :构建TEF 1δ (mousetranslationelongationfactor 1δ)的稳定表达系统。方法 :采用磷酸钙介导转染技术和G4 18细胞筛选法 ,以 pcDNA3.1/V5 His TOPO为表达载体 ,构建了TEF 1δ转基因CHO和COS7细胞系 ,WesternBlot分析与鉴定表达蛋白。结果 :在 10株转染和经G4 18反复筛选的CHO细胞系中 ,有 3株 (编码为COH pcDNA3.1 TEF 1δ # 3,# 6 ,# 14 )具有高效稳定表达的TEF 1δ编码蛋白质 (Mr约 31× 10 3 ) ,其余CHO细胞株的TEF 1δ蛋白质表达相对较弱或无表达。在 4株转染和经G4 18反复筛选的COS7细胞系中 ,4株细胞 (编码为COS7 pcCDNA3.1 TEF 1δ # 4 ,# 8,# 14和 # 17)均有高效稳定的TEF 1δ编码蛋白表达 ,相应的无转染组及载体对照组的CHO和COS7细胞均无TEF 1δ蛋白质表达。结论 :这两类TEF 1δ转基因哺乳动物细胞稳定表达系统已成功构建与鉴定 ,该表达系统的建立对于TEF 1δ这一新基因的生物学功能研究 ,尤其是镉的致癌作用与致癌机制的研究有重要应用价值。

TIF3转基因CHO和COS7细胞株的构建与鉴定

[目的 ]TIF3(MouseTranslationInitiationFacfor 3)是从镉转化BALB/c 3T3细胞中克隆出来的新基因 ,其在基因文库 (Gen Bank)的新添编号为AF2 710 72。为了对该基因的生物学功能进行研究 ,构建了TIF3转基因CHO和COS7细胞株并作了鉴定。[方法 ]采用磷酸钙介导转染技术和G418细胞筛选法 ,以pcD NA3 1/V5 His TOPO为表达载体 ,构建TIF3转基因CHO和COS7细胞株 ;应用WesternBlot技术对转基因表达产物进行分析与鉴定。实验设计分无转染组 (空白对照 )、载体转染组 (载体对照 )和目的基因转染组 (载体 +TIF3cDNA )。 [结果 ]结果显示 ,无论在CHO细胞还是COS7细胞 ,经转染和G418筛选后 ,无转染组的细胞 10 0 %死亡 ,而载体转染组和TIF3cDNA转染组的细胞形成较多的细胞集落。提示克隆化基因的细胞转染及G418筛选效果良好。经WesternBlot分析与鉴定 ,在 7株转染和经G418反复筛选的CHO细胞株中 ,有 3株具有高效稳定表达约 36kDa的TIF3编码蛋白质 ;在 4株转染和经G418反复筛选的COS7细胞株中有 2株也具有高效稳定的TIF3编码蛋白质表达 ,而无转染组和载体对照组的CHO和COS7细胞均缺乏此蛋白质表达。 [结论 ]本研究成功地构建了 3株TIF3转基因CHO细胞株和 2株TIF3转基因COS7细胞株。这两类TIF3转基因哺乳动物细胞稳定?

反义TIF3逆转镉转化BALB/c-3T3细胞的致癌性

为探讨反义TIF3能否逆转镉转化细胞的致癌性 ,用磷酸钙介导转染法和G418细胞筛选技术 ,建立CdCl2 转化BALB c 3T3细胞反义TIF3稳定表达系统 ,再用软琼脂检测和裸鼠致瘤试验对这些转基因细胞的致癌性逆转情况进行鉴定。结果显示CdCl2 转化BALB c 3T3细胞中反义TIF3表达可逆转这些细胞的转化表型 ,与非转染细胞和载体转染对照细胞比较 ,转染反义TIF3的镉转化细胞在软琼脂上所形成的锚非依赖性生长集落减少 2 5 %～ 70 %。转染反义TIF3基因的镉转化细胞可延迟裸鼠出现肿瘤的时间 ,而且这些肿瘤的大小显著变小 ,肿瘤重量平均下降 5 0 8%～ 5 5 1%。提示反义TIF3mRNA表达可逆转镉转化细胞的致癌性 ;

镉相关翻译启动因子TIF3致Ras癌基因蛋白的异常表达

目的研究镉相关翻译启动因子TIF3对多种细胞肿瘤相关基因表达的影响,探索镉的分子致癌机制。方法应用TIF3基因真核细胞稳定表达系统和Westernblot检测技术,用各种单克隆抗体检测细胞肿瘤相关基因蛋白的表达情况。结果相对于载体转染中国仓鼠卵巢(CHO)对照细胞,在4株具有高效稳定表达TIF3编码蛋白质的CHO细胞系中均有pan-ras癌基因蛋白异常表达,其编码蛋白(21kDa)含量均明显高于对照组;其余肿瘤相关基因蛋白如c-myc,c-jun,MDM2,ODC,p16,p53,CyclinD1的表达蛋白在TIF3转基因细胞与对照细胞之间未见明显差别。结论镉相关翻译启动因子TIF3是一种镉应答原癌基因,TIF3的超额表达可导致Ras癌基因蛋白异常表达,这可能是镉应答原癌基因TIF3的分子致癌机制。

硅转化BALB/c-3T3细胞基因组DNA异常甲基化的研究

目的 对硅转化细胞基因组DNA异常甲基化进行研究 ,探讨硅的表遗传致癌机制。方法 从结晶型硅 (Si)转化BALB/c 3T3细胞中提取基因组DNA ,经Mse1(甲基化非敏感性酶 )单独消化或Mse1和BstU1(甲基化敏感性酶 )联合消化 ,消化产物用甲基化敏感性内切酶指纹法 (MSRF)进行分析 ,差异显示出异常甲基化基因片段 ,进一步将异常甲基化DNA片段亚克隆和序列测定 ,再与基因文库中的基因进行类比分析。结果 发现硅转化细胞存在 6条异常甲基化DNA(其中 1条为高甲基化 ,5条有低甲基化现象 ) ,序列测定显示这些异常甲基化基因片段似乎来源于一些RNA转录和蛋白质翻译等基因家族。结论 DNA异常甲基化会导致基因表达激活或抑制 ,因此硅转化细胞基因组某些功能基因DNA异常甲基化导致的异常表达 。

Science on the Development of Standards and Their Compliance in a Representative Sample of Portuguese Tattoo Artists

Introduction: The number of Tattoo artists has been increasing and there are important Occupational Risks associated. The aim of this article was to describe the position of these professionals regarding the Recommendations and to analyze their compliance when working alone or accompanied. Methodology: It is a Mixed Exploratory Study, involving a quantitative component (Observational Analytical of transversal nature), operated through an online survey and, in a second phase, a qualitative one (Case Study), through the use of interviews. A representative sample of the population under study was obtained, considering a 90% confidence interval. The research project was approved by a Ethics Committee and informed consent was obtained. Presentation and Discussion of the Results: The sample considered 207 questionnaires and nine interviews. The compliance with Standards increases with experience;those who reported that they do not always comply are those who use less the Personal Protective Equipment (t = 2.659;p = 0.008). Compliance is also influenced by the Perception of Risk, information, social pressure (more accentuated by COVID19) and motivation to increase profit. Those who considered the Recommendations to be adequate were statistically associated with compliance with Collective Protection Measures. Regarding the compliance when working alone or not, 86.0% stated that they maintained the same posture;of those who answered the opposite, 85.7% complied more alone. Those with less education were statistically associated to less compliance with the rules when alone (X2 = 12.763;p = 0.005). Final Considerations: Previously unpublished data has been obtained, valuable to act effectively in this professional sector. It is fundamental to invest in training, as well as to elaborate Standards (developed jointly by Doctors/Safety Technicians and Tattoo artists). The organization of the Conventions should guarantee adequate conditions (area, access to disinfection/sterilization methods) and share Standards, promoting inspection and punishments for non-compliance, since they are the most unsafe places.

CFD modeling of methane distribution at a continuous miner face with various curtain setback distances

Knowledge of the airflow patterns and methane distributions at a continuous miner face under different ventilation conditions can minimize the risks of explosion and injury to miners by accurately forecasting potentially hazardous face methane levels. This study focused on validating a series of computational fluid dynamics(CFD) models using full-scale ventilation gallery data that assessed how curtain setback distance impacted airflow patterns and methane distributions at an empty mining face(no continuous miner present). Three CFD models of face ventilation with 4.6, 7.6 and 10.7 m(15, 25, and 35 ft) blowing curtain setback distances were constructed and validated with experimental data collected in a full-scale ventilation test facility. Good agreement was obtained between the CFD simulation results and this data.Detailed airflow and methane distribution information are provided. Elevated methane zones at the working faces were identified with the three curtain setback distances. Visualization of the setback distance impact on the face methane distribution was performed by utilizing the post-processing capability of the CFD software.

Role of CyclinD1 and CDK4 in the Carcinogenesis Induced by Silica

To study the role of cyclinD 1 and CDK4 in malignant transformation of human fetal lung diploid fibroblast cell line （2BS） induced by silica. Methods Recombination vectors with sense and antisense pXJ41-cyclinD1 and pXJ41-CDK4 were constructed, and then transfected into the malignant transformed cells induced by silica, respectively. At the same time, pXJ41-neo was used as the control. Results During the progress of the malignant transformation of 2BS cells induced by silica, cyclinD 1 and CDK4 were overexpressed. Antisense RNA suppressed cyclinD 1 and CDK4 gene expression in the antisense pXJ41-cyclinD1 and pXJ41-CDK4 transfected cells. Antisense RNA led to cell cycle arrest, resulting in lengthened G1 phase （the percentages of cells in the G1 phase changed from 45.1% to 52.7% and 58.0% for cyclinD1 and CDK4 transfected cells, respectively）, and eventually attenuated the increase of the proliferation of malignant transformed cells induced by silica. Compared with malignant transformed cells induced by silica, cells transfected with antisense pXJ41-cyclinD1 and pXJ41-CDK4 showed obviously reduced growth rates. On the 8th day, the suppression rates were 58.69 and 77.43% （the growth rate of malignant transformed cells induced by silica was 100%）, doubling time changed from 21.0 h to 31.4 h and 21.0 h to 42.7 h, respectively, the growth capacities on soft agar of cells transfected by antisense pXJ41-cyclinD1 and pXJ41-CDK4 decreased obviously. Conclusion CyclinD 1 and CDK4 play an important role in maintaining transformed phenotype of the cancer cells.

Co-effect of Demand-control-support Model and Effort-reward Imbalance Model on Depression Risk Estimation in Humans: Findings from Henan Province of China

Objective To investigate the co-effect of Demand-control-support （DCS） model and Effort-reward Imbalance （ERI） model on the risk estimation of depression in humans in comparison with the effects when they are used respectively. Methods A total of 3 632 males and 1 706 females from 13 factories and companies in Henan province were recruited in this cross-sectional study. Perceived job stress was evaluated with the Job Content Questionnaire and Effort-Reward Imbalance Questionnaire （Chinese version）. Depressive symptoms were assessed by using the Center for Epidemiological Studies Depression Scale （CES-D）. Results DC （demands/job control ratio） and ERI were shown to be independently associated with depressive symptoms. The outcome of low social support and overcommitment were similar. High DC and low social support （SS）, high ERI and high overcommitment, and high DC and high ERI posed greater risks of depressive symptoms than each of them did alone. ERI model and SS model seem to be effective in estimating the risk of depressive symptoms if they are used respectively. Conclusion The DC had better performance when it was used in combination with low SS. The effect on physical demands was better than on psychological demands. The combination of DCS and ERI models could improve the risk estimate of depressive symptoms in humans.