低温等离子体技术在殡仪场所空气消毒净化中的应用

为探讨低温等离子体技术在殡仪场所空气消毒净化中的应用效果和设计适用于殡仪场所的空气净化器,以双介质阻挡低温等离子体技术为核心,设计制造了殡仪场所用空气净化器样机,并对其去除空气中的细菌、总挥发性有机化合物(TVOC)、PM_(10)和PM_(2.5)的性能进行测试。结果显示,启动该消毒装置60 min后,殡仪馆内空气细菌总数平均下降率为64.60%,TVOC、PM_(10)和PM_(2.5)的净化率分别为45.24%,14.79%和24.06%。提示低温等离子体技术能有效降低殡仪馆内空气中的细菌总数及TVOC、PM_(10)、PM_(2.5)浓度。     

北京市冬季采暖期家用空气净化器净化效果评价

[目的]了解北京市采暖期住宅室内外颗粒物浓度,并评估家用净化器对室内颗粒物的净化效果。[方法]2015年11月—2016年1月间,选择北京市某区15户住宅,采用粉尘仪实时监测每户在开启家用型高效颗粒物空气(HEPA)净化器前后各24 h室内外PM_(2.5)和PM_(10)质量浓度,并在净化器开启后采用多通道仪监测室内PM_(2.5)、PM_(10)及其他多种粒径颗粒物浓度;采用室内外颗粒物浓度比值(I/O值)描述室内颗粒物相对室外的污染水平,并用配对样本的Wilcoxon符号秩检验比较净化前后I/O值差异;采用颗粒物清除率评价短时净化效率,并采用Friedman M检验和Wilcoxon符号秩检验进行比较。[结果]各户净化器运行前后的日均PM_(2.5)浓度的I/O值中位数及四分位数间距分别为1.79(2.63)和0.46(0.49),PM_(10)的I/O值中位数及四分位数间距分别为1.44(1.65)和0.40(0.46)。PM_(2.5)和PM_(10)净化前后的I/O值差异均有统计学意义(P0.05)。净化器开始运行到室内颗粒物浓度达稳定水平的时间约为3 h,对空气动力学直径≤0.3μm的颗粒物平均清除率为59.03%;0.3~0.5μm的颗粒物为63.08%;0.5~1μm的颗粒物为67.00%;PM_(2.5)为63.60%;PM_(10)为71.91%。不同粒径颗粒物的清除率差异具有统计学意义(P0.05)。[结论]家用型HEPA净化器可降低室内PM_(10)、PM_(2.5)及更小粒径颗粒物浓度,在3 h内降低不同粒径颗粒物浓度60%以上,其对不同粒径颗粒物的去除效果有所不同。     

纳米光催化空气净化器对甲醛及总挥发性有机物净化效果的实验研究

目的 研究纳米光催化空气净化器的两种机型对空气试验室中甲醛、总挥发性有机物(TVOC)的净化效率,了解其净化效果。方法 按照国家标准《空气净化器》(GB/T18801-2002)的步骤进行实验,根据实验结果计算空气净化器的洁净空气量和净化效果。结果 A空气净化器对空气实验室中甲醛和TVOC的洁净空气量和净化效率分别为28.80m~3/h、9.60％和46.80m~3/h、26.00％;B空气净化器对空气实验室中甲醛和TVOC的洁净空气量和净化效率分别为37.80 m~3/h、21.00％和140.40m~3/h、46.80％。结论 纳米光催化空气净化器对室内装修产生的主要污染物甲醛和TVOC有一定的净化作用,增加了活性炭过滤层的B空气净化器净化效果优于A空气净化器。     

车内空气污染物净化处理方法

对国内车内空气质量标准进行总结,指出解决车内空气质量的紧迫性。介绍了甲醛、笨、甲苯和TVOC等多种车内空气污染物的来源及危害。同时,对现已应用到车载空气净化器的气相污染物净化工艺,如,活性炭吸附技术、负离子净化技术、静电净化技术、光催化净化技术等进行了整理和归纳,指出各类净化技术的原理以及局限性。探究了光催化净化技术从最初的基于纳晶TiO_2的光催化净化技术到金属改性技术,再到非金属改性技术,最后到现在最具有发展前景的TiO_2/ACF光催化技术的发展历程。对光催化净化技术的应用前景做出展望,并简单设计基于光催化净化技术的车载空气净化器。     

新型组合式新风净化器去除SO_2的性能研究

目的分析一种应用于户式集中空调系统的新型新风净化器在不同SO_2浓度下的一次净化效率。方法该新型新风净化器由KOH改性活性炭与活性高锰酸钾球混合吸附过滤器、PP聚丙烯湿膜加湿过滤器和碳纤维负离子电离过滤器三部分组成。将4种过滤组件安装在风道式空气净化性能试验台上,在改变SO_2初始浓度条件下测试不同过滤组件的净化效率。结果该新型组合式新风净化器对SO_2的一次净化效率高达78.1%~80.2%。在空气SO_2浓度低于2.4 mg/m~3时,采用本新型组合式新风净化器净化后的空气SO_2浓度低于国家标准限值。结论该新型新风净化器较传统单一净化技术过滤器对SO_2的一次净化效率更具有优势。     

人员活动和空气净化器对支气管镜室空气微生物和颗粒物的影响

目的评价人员活动和空气净化器对支气管镜室空气微生物及颗粒物的影响。方法依照支气管镜室有无人员活动和空气净化器,将实验分成四组:动态无净化组、动态净化组、静态无净化组、静态净化组,在五个不同时间点(0、0.5、1、2、4 h)对室内空气进行采样和分析,用浮游菌法采集空气中的微生物并培养、计数,用DT-9881M激光尘埃粒子计数器检测颗粒物浓度,统计方法采用析因设计的方差分析。结果动态无净化组的细菌、真菌、总微生物(细菌+真菌)、PM_(2.5)和PM_(2.5~10.0)菌落数/浓度分别为(113.53±7.78)CFU/m~3、(89.67±7.17)CFU/m~3、(203.20±10.92)CFU/m~3、(86 557.20±4 158.29)个/m~3和(659.69±38.91)个/m~3,静态无净化组分别为(84.33±3.65)CFU/m~3、(65.00±2.65)CFU/m~3、(149.33±4.98)CFU/m~3、(45 812.64±1 279.61)个/m~3和(189.15±4.64)个/m~3,动态净化组分别为(84.80±8.08)CFU/m~3、(90.40±5.50)CFU/m~3、(175.20±9.22)CFU/m~3、(49 336.38±2 039.16)个/m~3和(218.36±7.02)个/m~3,静态净化组分别为(67.80±5.63)CFU/m~3、(38.27±3.70)CFU/m~3、(106.07±6.76)CFU/m~3、(29 772.53±2 212.93)个/m~3和(124.80±7.16)个/m~3,细菌、总微生物、PM_(2.5)、PM_(2.5~10.0)菌落数/浓度动态组高于静态组,无净化组高于净化组(均P0.05),真菌菌落数动态无净化组高于静态无净化组,静态净化组低于静态无净化组(均P0.05),动态净化组与无净化组间无明显差异(P=0.936)。结论人员活动增加支管镜室空气微生物和颗粒物的菌落数/浓度,空气净化器能降低支气管镜室空气中的细菌、总微生物和颗粒物的菌落数/浓度。     

多种空气净化器对甲醛净化效果分析

目的研究不同空气净化器对气体污染物的净化效果,为消费者选择室内空气净化器及生产厂家研发空气净化产品提供参考。方法以甲醛为代表性气态污染物,依据GB/T 18801—2008《空气净化器》的试验方法,通过在30 m3的密闭试验舱内添加一定量的甲醛,测试空气净化器作用前后的甲醛浓度,分别对市场上13台不同净化原理的空气净化器进行净化效果测试。结果不同净化原理的空气净化器之间对甲醛的净化效果差异有统计学意义;同时同一净化原理的不同空气净化器之间,对甲醛的净化效果也存在显著差异。复合型的空气净化器未必优于单一型,数据显示对甲醛净化效果比较好的主要是以活性炭等材料制成的空气净化器。结论 13台不同净化原理或同一净化原理的空气净化器对甲醛的净化效果差异较大。     

室内空气负离子浓度分布特征及其影响因素

为了解室内空气负离子浓度分布特征及影响因素,于2017年3—4月选取晴朗微风天气对高校图书馆某自习室内空气负离子、PM_(2.5)、PM_(10)、气温、相对湿度进行测定。结果显示,监测期间图书馆室内空气负离子浓度范围为60～320个/cm~3,浓度日最高值出现在9:00,最低值出现在15:00;图书馆内PM_(2.5)与PM_(10)浓度呈正相关(P0.01),空气负离子浓度与相对湿度呈正相关(P0.01),而空气负离子浓度与PM_(2.5)、PM_(10)、气温均无相关性。提示本次测定的室内空气负离子浓度波动较明显,其浓度可能与相对湿度有关。     

济南市室内外空气PM2.5关系及影响因素

目的了解普通居民室内外PM_(2.5)污染情况,探讨室内外PM_(2.5)关系及影响室内PM_(2.5)浓度的因素。方法于2018年9月—2019年1月从济南市历下区甸柳社区选择49户普通居民住宅采用RPPM_(2.5)系统监测3 d室内PM_(2.5)浓度、温度和相对湿度,通过调查问卷收集监测期间室内人员窗户开关、烹饪、空气净化器使用等信息。每次调查的时间间隔为30 d,共开展5次调查。从距离调查点位最近的环保监测站和气象监测站获取同期的室外空气PM_(2.5)浓度以及环境温度、相对湿度,利用混合效应模型分析室内PM_(2.5)浓度的影响因素。结果 2018年9月—2019年1月的5次调查显示室内PM_(2.5)浓度的几何均数分别为64.96、38.29、57.4、50.39和59.60μg/m~3,室外空气PM_(2.5)浓度几何均数分别为40.21、34.65、58.60、67.89和83.14μg/m3,室内外PM_(2.5)浓度呈正相关(rs=0.41,P0.001)。秋季室内外PM_(2.5)浓度比值(I/O)为1.17(P_(25)～P_(75):0.96～1.55),冬季I/O值为0.77(P25～P75:0.54～0.93),秋季I/O值明显高于冬季。混合效应模型分析结果显示,室外空气PM_(2.5)浓度(β=2.84×10~(-3),P0.001)、室内外相对湿度差绝对值(β=-0.02,P0.001)、室外风速(β=-0.87,P0.001)、空气净化器使用(β=-0.14,P=0.04)和室内除尘(β=0.19,P0.001)是影响室内PM_(2.5)水平的重要因素。混合效应模型的边际R~2(R_m~2)为0.55。结论济南市普通居民住宅室内外PM_(2.5)浓度关系在秋季和冬季存在明显的季节性差别,室外空气PM_(2.5)浓度、室内外相对湿度差绝对值、室外风速、空气净化器使用和室内除尘是影响室内PM_(2.5)浓度的重要因素。     

青岛市居民室内空气污染现状

目的了解青岛市城市居民室内环境空气质量状况,为今后开展城乡室内环境空气质量调查提供参考。方法 2018年随机抽取符合条件的59户家庭118个监测点(客厅和卧室)在非采暖季和采暖季分别测定温度、相对湿度、PM_(2.5)、PM_(10)、甲醛、苯、甲苯、二甲苯、NO_2、菌落总数、真菌总数。结果非采暖季室内空气出现真菌总数、NO_2、甲醛、PM_(10)和菌落总数污染,不合格率分别为48.4%(61/126)、37.3%(47/126)、20.6%(26/126)、4.76%(6/126)和3.97%(5/126);采暖季室内空气出现PM_(10)、PM_(2.5)、真菌总数、菌落总数和甲醛污染,不合格率分别为39.8%(43/108)、37.0%(40/108)、28.7%(31/108)、9.26%(10/108)和7.41%(8/108)。非采暖季室内与室外污染物(NO_2、PM_(2.5)、PM_(10))质量浓度差异均有统计学意义(t值分别为14.3、7.10和4.95,P<0.01),而采暖季室内与室外污染物(NO_2、PM_(2.5)、PM_(10))质量浓度差异均无统计学意义(t值分别为1.08、0.35和1.53,P> 0.05)。Spearman秩相关分析显示,座内空气中菌落总数与甲醛、真菌总数呈正相关(r_s值分别为0.303和0.248,P<0.01);真菌总数与温度、相对湿度和NO_2呈正相关(r_s值分别为0.273、0.280和0.235,P<0.01),真菌总数与苯、甲苯、二甲苯浓度呈负相关(r_s值分别为-0.208、-0.261和-0.181,P<0.01)。结论青岛市城市居民室内空气主要污染物为甲醛、NO_2、真菌和颗粒物。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.