Evaluation of ocular protection filters in field situations

A computer program has been developed to simulate eye movement during pursuit tracking to test the effectiveness of filters protecting the eyesight of individuals exposed to laser radiation. Two types of retinal damage are considered: macular lesions and retinal injury causing vitreous or subretinal hemorrhage. The retinal damage caused by optical radiation in the visible and near infrared of the spectrum differs from almost all other types of hazards in their proabilistic nature. That is, a small movement of the laser beam or change of eye position decreases or increases the probability of injury by several orders of magnitude. A laser beam combines the problem of a small source with extreme directionality with the probabilistic nature of this hazard location in space, and we now add the probabilistic nature of the action of the protective filter, i.e., a dependence upon angle of incidence. From this combination, an even more probabilistic picture of injury or disablement emerges. When it is necessary to plan the probabilities during military operations of mission fulfillment or injury with regard to various types of lasers in the battlefield ++environment, the problem must be analyzed very carefully. Our solution of the problem indicates the type of injuries to be expected and their dependence upon the various parameters of the angle of incidence of the lasers on the protective filters in the viewing system.     

Mandatory use of eye protection prevents eye injuries in the metal industry

BACKGROUND: Eyes are frequently injured in occupational accidents. What is the preventive effect of mandatory eye protection in metalworking? METHODS: The injury incidence was determined before and after eye protection became mandatory in a metalworking yard. RESULTS: The incidence declined from 6.09 to 0.42 injuries per million working hours after eye protection became mandatory. CONCLUSIONS: Mandatory eye protection among metalworkers in Norway has high potential for preventing eye injuries and should be implemented.     

Evaluation of personal inhalable aerosol samplers with different filters for use during anthrax responses

Risk of inhalation exposure to viable Bacillus anthracis (B. anthracis) spores has primarily been assessed using short-term, stationary sampling methods which may not accurately characterize the concentration of inhalable-sized spores reaching a person's breathing zone. While a variety of aerosol sampling methods have been utilized during previous anthrax responses, no consensus has yet been established for personal air sampling. The goal of this study was to determine the best sampler-filter combination(s) for the collection and extraction of B. anthracis spores. The study was designed to (1) evaluate the performance of four filter types (one mixed cellulose ester, MCE (pore size = 3 µm), two polytetrafluoroethylene, PTFE (1 and 3 µm), and one polycarbonate, PC (3 µm)); and (2) evaluate the best performing filters in two commercially available inhalable aerosol samplers (IOM and Button). Bacillus thuringiensis kurstaki [Bt(k)], a simulant for B. anthracis, served as the aerosol challenge. The filters were assessed based on criteria such as ability to maintain low pressure drop over an extended sampling period, filter integrity under various environmental conditions, spore collection and extraction efficiencies, ease of loading and unloading the filters into the samplers, cost, and availability. Three of the four tested collection filters—except MCE—were found suitable for efficient collection and recovery of Bt(k) spores sampled from dry and humid as well as dusty and clean air environments for up to 8 hr. The PC (3 µm) filter was identified as the best performing filter in this study. The PTFE (3 µm) demonstrated a comparable performance, but it is more expensive. Slightly higher concentrations were measured with the IOM inhalable sampler which is the preferred sampler's performance criterion when detecting a highly pathogenic agent with no established “safe” inhalation exposure level. Additional studies are needed to address the effects of environmental conditions and spore concentration. The data obtained in this investigation are crucial for future efforts on the development and optimization of a method for assessing inhalation exposure to B. anthracis.     

Evaluation of respirator filters for asbestos fibers

Fiber aerosols are known to have different aerodynamic behaviors than spherical particles and usually carry higher electrostatic charges. We investigated the effects of flow rate and charge status of filter cartridges on the penetration of spherical and fiber aerosols. Four types of test respirator filters were selected: two for passive respirators, one for a powered respirator, and one disposable respirator. Surface charges on respirator filters were determined using a noncontact field electrostatic field meter. Penetration tests were performed for filter cartridges before and after charge neutralization. The surface charge measurements on the respirator filters showed that some filters, including those used in disposable face masks, are charged to enhance the collection efficiency. Only high-efficiency particulate air filters performed consistently for both spherical test aerosols and the three types of asbestos fibers. The surface charge potential of filter cartridges and flow rate did not appear to affect the performance of these filters. In contrast to the high-efficiency filters, the aerosol penetration performance of low-efficiency filters and face masks deteriorated when the charge potential on the filter was removed. Our data also showed that the surface charges decreased in a high-temperature, high-humidity environment and disappeared after 1 week. Deposition of spherical particles and fibers in the charged disposable facemask filter was enhanced. For charged-neutralized, low-efficiency filter cartridges, asbestos fibers may penetrate more than spherical particles with a mean particle size of 0.3 microm diameter.     

用于蚊蠓调查的双灯诱蚊器的设计与使用

蚊是多种急性传染病尤其是乙型脑炎、登革热和黄热病的主要传播媒介生物之一,其严重危害人类健康和生命安全。为了贯彻国家出入境检验检疫局关于继续做好全国口岸媒介生物本底调查的通知,青岛出入境检验检疫局机场办事处与青岛大卫洗消技术研究所共同研制了双灯诱蚊器,以便于各口岸进行蚊蠓的本底调查。现将双灯诱蚊器的设计与使用方法介绍如下：     

Microwave technology in dental and eye prosthesis

The paper outlines the specific features of using microwave technologies in dental and eye prostheses designed in Russia in 1992-1998. Thermal, microwave, and combined polymerizations of plastic materials used in prosthesis are compared. A Denta microwave unit is presented, which realizes a combined microwave technology.     

The use of vena caval filters.

Deep vein thrombosis with pulmonary embolus is a frequent event, which is usually treated by anticoagulant drug therapy alone. Caval filters tend to be used infrequently in most centres in the UK. This article intends to help hospital doctors make use of these devices appropriately.     

Periodontal effects and dental caries associated with smokeless tobacco use

The prevalence of smokeless tobacco use has been increasing in the United States with concomitant social, medical, legal, and regulatory ramifications. This paper examines the association between the use of smokeless tobacco and the occurrence of periodontal disease and dental caries. Existing literature consists primarily of case reports and cross-sectional studies among teenagers. The limited evidence suggests an association between smokeless tobacco use and gingival recession. There is insufficient evidence to support any associations between smokeless tobacco use and gingivitis, periodontitis, or dental caries. Methods to improve future epidemiologic research to examine possible associations between smokeless tobacco use and periodontal effects or dental caries are discussed.     

论常见电磁辐射对眼的危害及防护

随着科技的发展，电磁辐射污染直接影响着环境及人体健康。本文对常见的电磁辐射对于眼睛的危害进行了论述，并提出了减少眼睛对于电磁辐射损伤的相关措施。     

Quality of life and stability of tooth color change at three months after dental bleaching

Purpose

Intracoronary bleaching is a minimally invasive, alternative treatment that addresses aesthetic concerns related to non-vital teeth discoloration. However, to the best of our knowledge, no studies have assessed the psychosocial impacts of such procedures on patients’ aesthetic perceptions. The aim of this study was to evaluate aesthetic perceptions and the psychosocial impact of patients up to 3 months after their teeth had been bleached with hydrogen peroxide (35%) and carbamide peroxide (37%) using the walking bleach technique.

Methods

The patients were randomly divided into two groups according to the bleaching agent used: G1?=?hydrogen peroxide 35% (n?=?25) and G2?=?carbamide peroxide 37% (n?=?25). Non-vital bleaching was performed in four sessions. Color was objectively (ΔE) and subjectively (ΔSGU) evaluated. Aesthetic perception and psychosocial factors were evaluated before, 1 week and 1 month after the bleaching using the Oral Health Impact Profile (OHIP) and Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) questionnaires.

Results

The color change (ΔE) values at 1 month were G1?=?16.80?±?6.07 and G2?=?14.09?±?4.83. These values remained stable until the third month after treatment (p?>?0.05). There was a decrease in the values of OHIP-aesthetics and PIDAQ after treatment versus baseline (p?<?0.05). This status was maintained through the third month after treatment.

Conclusions

Both agents were highly effective and had a positive impact on the aesthetic perception and psychosocial impact of patients, values that also remained stable over time. Non-vital bleaching yields positive and stable impacts on aesthetic perception and psychosocial factors. ClinicalTrials.gov identifier NCT02718183.

     

漂白土超早期干预与百草枯中毒对预后的影响

目的 观察院前第一时间给予漂白土灌服的百草枯(PQ)中毒患者的存活率。 方法 将2009-2015年420例PQ中毒患者分为两组,进行回顾性分析,常规组患者234例,在当地医院单纯清水洗胃,未给予漂白土灌服,转来我院后给予漂白土运用;早期干预组患者186例,当地医院清水洗胃后立即给予漂白土灌服,甘露醇导泻,转来我院后再次给予漂白土运用。观察两组的存活时间、存活率。 结果 早期干预组病死率32.3%,死者存活时间15 d,常规治疗组病死率45.3%,死者存活时间11 d,两组数据比较,差异均有统计学意义(P<0.05或0.01)。 结论 早期漂白土干预可提高PQ中毒的抢救成功率。加强基层医院PQ中毒急救培训,对提高PQ中毒患者存活率具有重要意义。