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271.
为加强国内食品包装材料的安全卫生控制及促进我国对外贸易的顺利进行。解析了欧盟对食品接触包装材料的管理体系,重点介绍了与食品接触塑料材料和制品的指令、法规以及三层结构体系,阐述了各种法规及指令的制定过程。  相似文献   
272.
陈红军 《中国造纸》2016,35(2):71-73
介绍一种新型树脂控制剂在卫生材料衬纸生产中的应用。该助剂可以有效地控制生产系统内产生的树脂(胶黏物),减少因胶黏物造成的纸张尘埃和纸机断纸,提高纸机系统运行性能,保持抄造系统清洁,从而减少纸机停机次数,提高生产效率。  相似文献   
273.
Abstract

Exposure assessment models are deterministic models derived from physical–chemical laws. In real workplace settings, chemical concentration measurements can be noisy and indirectly measured. In addition, inference on important parameters such as generation and ventilation rates are usually of interest since they are difficult to obtain. In this article, we outline a flexible Bayesian framework for parameter inference and exposure prediction. In particular, we devise Bayesian state space models by discretizing the differential equation models and incorporating information from observed measurements and expert prior knowledge. At each time point, a new measurement is available that contains some noise, so using the physical model and the available measurements, we try to obtain a more accurate state estimate, which can be called filtering. We consider Monte Carlo sampling methods for parameter estimation and inference under nonlinear and non-Gaussian assumptions. The performance of the different methods is studied on computer-simulated and controlled laboratory-generated data. We consider some commonly used exposure models representing different physical hypotheses. Supplementary materials for this article are available online.  相似文献   
274.
PurposeTo investigate if the application of Blephagel, an eyelid cleansing gel, causes subjective and/or objective cooling effects by measuring ocular symptomology and temperature.MethodsTwenty-five healthy subjects underwent baseline non-invasive temperature measurements on the closed upper eyelid (centrally, nasally, and temporally) and ocular surface temperature (OST) on both eyes using an infrared camera. A standard application of Blephagel was then applied to the closed upper eyelid and eyelashes with a sterile cotton-wool to one eye selected at random. Temperature measures were then repeated on both eyes after 30–60, 120–150, and 180–210 s. At each interval, subjects rated the comfort and any cooling sensation of each eye on a 0–10 scale.ResultsAfter application of the gel, there was a significant difference in temperature at all locations on the eyelid between the test and control eyes over time (F = 9.322, p < 0.001). Post hoc analysis revealed this was significant from 30 to 60 s interval (36.3 ± 1.1 °C versus 37.2 ± 0.7 °C; p < 0.001) and the 120–150 s interval (36.8 ± 0.8 °C versus 37.2 ± 0.6 °C; p < 0.001). There was no significant variation between the OST locations over time (F = 3.350, p = 0.07). With respect to symptoms, there was a significant increase in cooling sensation in the test eye compared to the control eye over time (F = 10.438, p < 0.001), that remained throughout the experiment.ConclusionsBlephagel produces a reduction in temperature of the eyelids that is accompanied with a subjective cooling sensation.  相似文献   
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276.
The aim of this study was to check the compliance of street food vendors hygienic practices with requirements of the Codex code of practice - general principles on food hygiene and of the Regulation (EC) No. 852/2004. The materials were 110 street food vendors located in Athens, Greece. Specially designed questionnaire allowed fast data collection. The lowest ratings were found in the hygiene of food preparation and serving, that was related to basic infrastructure, especially the protection of light bulbs from glass spreading in case of breaking, and protection of hair from falling into food by wearing sufficient hair covers or caps. Much higher ratings were found in separation of fresh food from ready-to-eat one and in the section of personal hygiene - lack of visible cuts or skin disease symptoms on hands. One of the most interesting findings is that street vendors selling meat or fish meals obtained higher ratings than vegetable or fruit ones. A greater effort should be made to increase hygiene level especially in the case of small mobile food vendors. Because of variation in hygiene level there is a need for more inspections covering greater number of street food vendors. Due to high popularity of street food and its importance for tourism, more effort should be made to improve the degree of compliance with the hygiene requirements. The fast observation questionaire used in this study allowed rapid assessment of implementation of hygiene principles. Further research is needed to explain why, despite food safety authorities licencing and inspection, implementation of hygiene principles by street food vendors is often incomplete and what factors affect the correct operation.  相似文献   
277.
Poor hand hygiene is a leading cause for the spread of foodborne illnesses in the foodservice industry. A series of complex motivational interventions must be employed to permanently change the behavior of workers, to increase their compliance and sustain appropriate levels of proper hand hygiene. Unlike the healthcare industry, which uses large, costly multi-modal behavior modification strategies, the foodservice industry must deploy rapid, cost-efficient strategies that take into account a high employee turnover rate and diverse demographics. This paper reviews the current motivational models used in the foodservice industry and examines the habitual nature of complying with good hand hygiene. It also reviews current techniques to increase hand hygiene compliance using clues from three of the five basic senses (sight, hearing, and smell) and two mechanisms (context-bridging and disgust). Lastly, the current model for habit intervention is evaluated, and its possible applications in the foodservice industry with additional reminders are accessed. We believe that this review will provide foodservice managers the background, theoretical basis and practical applications for making long-term changes in their employees on this and similar critical behaviors in foodservice.  相似文献   
278.
Chronic kidney disease has become a worldwide public health problem, and it negatively affects oral health. However, the data of the hemodialysis (HD) patients in Chinese population is unknown. This study was aimed to evaluate the dental health status and oral hygiene behavior of the HD patients in China. Patients undergoing HD therapy at two hospitals were asked to finish a questionnaire and receive dental examination (DMF‐T). A total of 306 patients, aged 24–88 (58.09 ± 14.06), took part in this study. Although majority of the patients (77.78%) brushed their teeth at least twice a day, few (less than 5%) had ever used dental floss or mouthwash. More than half of the patients have not visited a dentist since the commencement of HD therapy. The dental examination showed that DMF‐T was 9.63 ± 7.54, and the number of filled teeth (F‐T) was only 0.70 ± 1.48. Moreover, the average caries restoration ratio and replacement index were 17.57% and 32.59%, respectively. HD therapy seems to prevent patients from visiting a dentist, and there is a great need for dental treatment for Chinese HD patients.  相似文献   
279.
280.
Public service psychologists have led in the systematic use of new approaches to assessment, diagnosis, therapeutic interventions, and organizational management of mental and physical disorders. Outstanding examples include the MMPI and its successor developed at the University of Minnesota; elaboration of its 2-point code types and additional clinical scales at VA Medical Centers; David Wechsler’s work on intelligence and memory measurement at Bellevue Hospital, New York; early adoption of group therapy, early development of family therapy, token economies, and adult mental hygiene clinics; and finally the impetus for the development of accreditation in professional psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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