The Annals of occupational hygiene最新文献

{"title":"Response to Article by Prof. Hans Kromhout, Hygiene Without Numbers.","authors":"P. Griffin, A. Curran","doi":"10.1093/annhyg/mew054","DOIUrl":"https://doi.org/10.1093/annhyg/mew054","url":null,"abstract":"","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"146 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114634295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occupational Exposure to Polycyclic Aromatic Hydrocarbons in Polish Coke Plant Workers.","authors":"Joanna Zając, E. Gomółka, B. Maziarz, W. Szot","doi":"10.1093/annhyg/mew049","DOIUrl":"https://doi.org/10.1093/annhyg/mew049","url":null,"abstract":"Assessment of occupational exposure to polycyclic aromatic hydrocarbons (PAHs) is an urgent and important task to prevent workers' illnesses. 1-Hydroxypyrene is one of the most commonly used biomarkers. The presented study assessed exposure to PAHs molecules among 619 individuals, men working in coke plant. Average number of years spent on working posts in exposition to PAHs was 31.5 years with standard deviation = 5.3. About 35% were smokers with 14.7 cigarettes per day. For each individual, 1-hydroxypyrene concentration in urine samples was measured. Urine 1-hydroxypyrene concentration correlated with air PAHs concentration. Difference between smokers and non-smokers was statistically significant. The median value for post-shift samples was 1.3 µg g-1 and for pre-shift sample concentration reached 0.3 µg g-1 Maximal assessed concentration was 7.6 µg g-1 among pre-shift samples and 27.8 µg g-1 among post-shift samples. The most exposed working posts were coke oven workers and coal derivatives production workers. Results obtained in presented study are relatively low in comparison to other countries or other Polish results but for further improvement a regular measurement of any PAHs' biomarker should be included to standard periodic health examinations for coke plant workers.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124159547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Miniature Respirable Sampler for In-mask Sampling: Part 2-Tests Performed Inside the Mask.","authors":"R. Mogridge, P. Stacey, James Forder","doi":"10.1093/annhyg/mew051","DOIUrl":"https://doi.org/10.1093/annhyg/mew051","url":null,"abstract":"This paper is the second in a series of two describing the performance of a miniature and low-weight respirable sampler designed to fit inside filtering facepiece (FFP) and half-mask type respirators. The first paper described the design of the miniature sampler and evaluated the particle and collection performance of the miniature sampler. This paper assesses its comparability with the traditional inward leakage measurement technique, and its safe use. Simultaneous mass measurements of a respirable sodium chloride aerosol were taken inside a total inward leakage chamber by a miniature sampler and by sodium flame photometry. Direct side-by-side comparison of the two methods yielded excellent correlation (R 2 = 0.99), as did comparison when sampling from inside four different masks when worn by a breathing Sheffield dummy head. In addition, comparison tests were carried out using three models of FFP worn by human volunteers both with and without the miniature sampler, in order to test whether or not the presence of the miniature sampler negatively affected the protection offered. The difference between the tests carried out with the miniature sampler and without the miniature sampler was not statistically significant (P = 0.3). In all cases, the masks performed within their protection class, whether the miniature sampler was fitted or not. We therefore conclude that the miniature sampler does not significantly affect the protection offered by the masks. The miniature sampler may prove a viable option for in-mask measurements of respirable dust where low air concentrations of hazardous material are expected.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"60 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130742314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Validity and Applicability of Using a Generic Exposure Assessment Model for Occupational Exposure to Nano-Objects and Their Aggregates and Agglomerates.","authors":"C. Bekker, E. Voogd, W. Fransman, R. Vermeulen","doi":"10.1093/annhyg/mew048","DOIUrl":"https://doi.org/10.1093/annhyg/mew048","url":null,"abstract":"BACKGROUND\u0000Control banding can be used as a first-tier assessment to control worker exposure to nano-objects and their aggregates and agglomerates (NOAA). In a second tier, more advanced modelling approaches are needed to produce quantitative exposure estimates. As currently no general quantitative nano-specific exposure models are available, this study evaluated the validity and applicability of using a generic exposure assessment model (the Advanced REACH Tool-ART) for occupational exposure to NOAA.\u0000\u0000\u0000METHOD\u0000The predictive capability of ART for occupational exposure to NOAA was tested by calculating the relative bias and correlations (Pearson) between the model estimates and measured concentrations using a dataset of 102 NOAA exposure measurements collected during experimental and workplace exposure studies.\u0000\u0000\u0000RESULTS\u0000Moderate to (very) strong correlations between the ART estimates and measured concentrations were found. Estimates correlated better to measured concentration levels of dust (r = 0.76, P < 0.01) than liquid aerosols (r = 0.51, P = 0.19). However, ART overestimated the measured NOAA concentrations for both the experimental and field measurements (factor 2-127). Overestimation was highest at low concentrations and decreased with increasing concentration. Correlations seemed to be better when looking at the nanomaterials individually compared to combined scenarios, indicating that nanomaterial-specific characteristics are not well captured within the mechanistic model of the ART.\u0000\u0000\u0000DISCUSSION\u0000Although ART in its current state is not capable to estimate occupational exposure to NOAA, the strong correlations for the individual nanomaterials indicate that the ART (and potentially other generic exposure models) have the potential to be extended or adapted for exposure to NOAA. In the future, studies investigating the potential to estimate exposure to NOAA should incorporate more explicitly nanomaterial-specific characteristics in their models.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122718540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"When Are Risk Analyses on Job Titles Informative?","authors":"R. Vermeulen","doi":"10.1093/annhyg/mew047","DOIUrl":"https://doi.org/10.1093/annhyg/mew047","url":null,"abstract":"In the January issue of the Annals of Occupational Hygiene, we published a paper by Garabrant et al. (2016a), ‘Mesothelioma among Motor Vehicle Mechanics: An updated review and Meta-analyses’. The paper described an update from a 2004 metaanalyses performed largely by the same authors. The updated meta-analyses included 10 case–control studies, 1 cohort study, and 5 proportional mortality ratio/ standardized mortality odds ratio (OR) studies. The results of the meta-analyses indicated that the summary risk estimates were generally <1 and that no statistically significant increases in mesothelioma were observed. The authors therefore concluded that ‘this meta-analysis of the epidemiologic studies provides evidence that motor vehicle mechanics, including workers who were engaged in brake repair, are not at an increased risk of mesothelioma’ (Garabrant et al., 2016a). This conclusion is similar to the conclusion of the 2004 paper that concluded, based on seven studies of which six studies were also included in the current meta-analyses, that ‘employment as a motor vehicle mechanic does not increase the risk of developing mesothelioma’ (Goodman et al., 2004). Although there were some methodological differences between the two meta-analyses in how the quality of the studies was scored the two ranking systems showed overall good correspondence and resulted in a similar classification in quality categories. Analyses by quality of the studies did not show an association between study quality and the log OR and of the 10 studies only 2 studies had an OR > 1. All together, the conclusion of the papers seemed therefore scientifically justified. However, there is a question in how one should interpret this result. As Teschke (2016) pointed out in her letter to the editor, the issue of interest is whether chrysotile asbestos exposure among mechanics causes mesothelioma. Mechanics perform a variety of tasks and not all mechanics will be involved in break repair. The ones that do in turn may only do so for part of the time. Using broad categories of job titles (e.g. garage workers, auto repair and related services, and auto engineers) are therefore likely poor proxies of chrysotile asbestos exposure. As such although the conclusion of the paper is correct in that no elevated risks are found among motor vehicle mechanics as a whole this cannot be equated to mean that there is no risk of mesothelioma among mechanics that were involved in break repair and that had potential chrysotile exposure. In their answer to the letter to the editor, Garabrant et al. (2016b) indicated that the results may indicate that motor vehicle mechanics and brake workers are perhaps not at increased risk of mesothelioma as they may not have sufficient exposure to observe an increased risk. Again, this statement is correct at the job-title level but may not hold for specific subgroups and/or individuals that may have been higher exposed. As such, the question can and perhaps should be ra","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131504609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an Interception Glove Sampler for Skin Exposures to Aromatic Isocyanates.","authors":"H. Harari, D. Bello, S. Woskie, C. Redlich","doi":"10.1093/annhyg/mew052","DOIUrl":"https://doi.org/10.1093/annhyg/mew052","url":null,"abstract":"OBJECTIVES\u0000Skin is an important exposure route for isocyanate chemicals and contributes to systemic sensitization. Methods for assessing skin exposure are currently limited and generally rely upon removal (e.g. tape-strip) techniques prone to underestimation. The aim of this study is to (i) develop and field test an interception-based hand exposure sampler to monitor potential skin exposure to isocyanates in the workplace, (ii) to develop an analytical method based on ultra-high-performance liquid chromatography-UV absorbance-tandem mass spectrometry (UHPLC-UV-MS/MS) for analyzing glove samples; and (iii) compare it with tape-stripping skin sampling method.\u0000\u0000\u0000METHODS\u0000Laboratory investigations assessed different glove materials/fabrics, methods for impregnating with 1-(9-anthracenylmethyl)piperazine (MAP) derivatizing agent, methylene diphenyl diisocyanate (MDI) uptake and recovery, and durability. Following use, gloves were dissected into sections corresponding to different spatial regions (finger, palm) and analyzed using a newly developed UHPLC-UV-MS/MS method capable of differentiating and quantitating different MDI isomers with high sensitivity. Performance of the glove sampler was further assessed in a pilot field study using six workers.\u0000\u0000\u0000RESULTS\u0000A MAP-impregnated thin cotton glove sampler and UHPLC-UV-MS/MS analytical method for detecting MDI were successfully developed in laboratory studies. In subsequent field studies, a total of 384 samples from 14 glove pairs identified full-shift exposures ranged from 0.01 to 306 µg of 4,4'-MDI/worker for each hand. Surface area adjusted MDI values measured with the glove sampler (0.13-572ng MDI cm-2) were considerably higher (~400-fold) than values obtained with tape stripping.\u0000\u0000\u0000CONCLUSION\u0000A glove sampler and a novel UHPLC-UV-MS/MS analytical method were developed to quantitatively measure MDI skin exposure. The novel interception technique overcomes inherent limitations of removal techniques for measuring isocyanate skin exposure and may be useful in exposure surveillance and future research on isocyanate's health risks.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"313 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133827002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential Counting of Asbestos Using Phase Contrast and Fluorescence Microscopy.","authors":"Tomoki Nishimura, Maxym Alexandrov, Takenori Ishida, R. Hirota, Takeshi Ikeda, K. Sekiguchi, A. Kuroda","doi":"10.1093/annhyg/mew055","DOIUrl":"https://doi.org/10.1093/annhyg/mew055","url":null,"abstract":"Considering the increasing use of various asbestos substitutes, asbestos risk management in many industries may require accurate techniques for detecting and distinguishing asbestos from non-asbestos fibers. Using fluorescently labeled asbestos-binding proteins, we previously developed a novel method for detection and counting of asbestos fibers under fluorescence microscopy (FM). This method can provide speedy, on-site detection and identification of the asbestos fibers and has higher sensitivity than phase contrast microscopy (PCM). However, current asbestos exposure limits are derived from risk assessments based on epidemiological studies that were conducted using PCM fiber counts. Therefore, the sensitivity of asbestos testing should be maintained at PCM level to properly assess compliance with these limit values. Here, we developed and tested a novel application of FM as a differential counting method that complements PCM analysis and is fully compatible with the PCM-based epidemiological data. In the combined PCM-FM method, the fluorescent asbestos-binding probe is applied prior to filter clearing. The method makes it possible to easily switch between two microscopic techniques while analyzing the same fields of view: PCM is used for counting fibers, and FM for differentiating asbestos from non-asbestos fibers. Using airborne dust samples from demolition sites in Japan, we compared PCM-FM with scanning electron microscopy (SEM)-based differential counting method. Statistical analysis indicated a slight conservative bias of PCM-FM method, combined with relatively high variability across the full range of fiber concentrations in our sample set. Using correlative microscopy, we also evaluated the specificity of FM staining, which is a potential cause of variability between the two methods. The energy-dispersive X-ray analysis indicated that ~95% of fluorescently stained fibers in the demolition site samples were correctly identified as asbestos. While further research is needed to fully clarify the causes of variability between FM- and SEM-based differential counting, PCM-FM could be used for rapid and selective detection of asbestos fibers in field samples.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"75 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121009103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Miniature Respirable Sampler for In-mask Sampling: Part 1-Particle Size Selection Performance.","authors":"P. Stacey, A. Thorpe, R. Mogridge, Taekhee Lee, M. Harper","doi":"10.1093/annhyg/mew053","DOIUrl":"https://doi.org/10.1093/annhyg/mew053","url":null,"abstract":"The Health and Safety Laboratory has developed a miniature respirable sampler to gain a better understanding of the exposure of workers to hazardous substances when they are wearing respiratory protective equipment (RPE) or helmets with visors in the workplace. The study was in two parts and the first part, described herein, was to develop the sampler and test its collection characteristics. Assessment of the impact of the sampler on RPE safety and its comparability with traditional laboratory-based approaches to measure protection factors was discussed in a second article. The miniature sampler (weight-5.4g, length-13mm) was designed to fit into the space available between the nose and chin of an individual inside a filtering facepiece type mask and has a radially omnidirectional inlet with a porous foam particle selector that allows the collection of the respirable fraction on a downstream filter. The sampling efficiency was compared with the respirable convention. A close match with the respirable convention was obtained at a flow rate of 1 l min-1 and the 50% penetration cut off value (d 50) was 4.08 µm. After 3 hours sampling in high humidity (95%), the penetration curve had shifted towards smaller particle sizes (d 50 = 3.81 µm) with 88% of the calculated bias values within 10%. The miniature sampler measured respirable dust and crystalline silica mass concentrations comparable with performance of the Safety In Mines Personal Dust Sampler (SIMPEDS), commonly used in Great Britain, at a flow rate of 0.8 l min-1 The d 50 for the miniature sampler at 0.8 l min-1 (4.4 µm) is within 5% of the d 50 of the SIMPEDS at its prescribed flow rate of 2.2 l min-1 (4.2 µm). These results indicated that the miniature sampler was a good candidate to proceed with tests with RPE described in the second part of this series of two papers.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116476521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compliance with the Use of Medical and Cloth Masks Among Healthcare Workers in Vietnam.","authors":"A. Chughtai, H. Seale, T. C. Dung, A. Hayen, B. Rahman, C. Raina MacIntyre","doi":"10.1093/annhyg/mew008","DOIUrl":"https://doi.org/10.1093/annhyg/mew008","url":null,"abstract":"BACKGROUND\u0000Masks are often worn in healthcare settings to prevent the spread of infection from healthcare workers (HCWs) to patients. Masks are also used to protect the employee from patient-generated infectious organisms but poor compliance can reduce efficacy. The aim of this study was to examine the factors influencing compliance with the use of medical and cloth masks amongst hospital HCWs.\u0000\u0000\u0000METHODS\u0000HCWs compliance with the use of medical and cloth masks was measured over a 4-week period in a randomized controlled trial in Vietnam. HCWs were instructed to record their daily activities in diary cards. Demographic, clinical, and diary card data were used to determine the predictors of compliance and the relationship of compliance with infection outcomes.\u0000\u0000\u0000RESULTS\u0000Compliance rates for both medical and cloth masks decreased during the 4 weeks: medical mask use decreased from 77 to 68% (P < 0.001) and cloth masks from 78 to 69% (P < 0.001). The presence of adverse events (adjusted RR 0.90, 95% CI 0.85-0.95), and performing aerosol-generating procedures (adjusted RR 0.78, 95% CI 0.73-0.82) were negatively associated with compliance, while contact with febrile respiratory illness patients was positively associated (adjusted RR 1.14, 95% CI 1.07-1.20). Being compliant with medical or cloth masks use (average use ≥70% of working time) was not associated with clinical respiratory illness, influenza-like illness, and laboratory-confirmed viral infection.\u0000\u0000\u0000CONCLUSION\u0000Understanding the factors that affect compliance is important for the occupational health and safety of HCWs. New strategies and tools should be developed to increase compliance of HCWs. The presence of adverse events such as discomfort and breathing problems may be the main reasons for the low compliance with mask use and further studies should be conducted to improve the design/material of masks to improve comfort for the wearer.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126151777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Multiple Measures of Noise Exposure in Paper Mills.","authors":"R. Neitzel, M. Andersson, E. Andersson","doi":"10.1093/annhyg/mew001","DOIUrl":"https://doi.org/10.1093/annhyg/mew001","url":null,"abstract":"BACKGROUND\u0000Noise exposures are associated with a host of adverse health effects, yet these exposures remain inadequately characterized in many industrial operations, including paper mills. We assessed noise at four paper mills using three measures: (i) personal noise dosimetry, (ii) area noise measurements, and (iii) questionnaire items addressing several different aspects of perceived noise exposure.\u0000\u0000\u0000METHODS\u0000We assessed exposures to noise characterized using the three measures and compared the relationships between them. We also estimated the validity of each of the three measures using a novel application of the Method of Triads, which does not appear to have been used previously in the occupational health literature.\u0000\u0000\u0000RESULTS\u0000We collected 209 valid dosimetry measurements and collected perceived noise exposure survey items from 170 workers, along with 100 area measurements. We identified exposures in excess of 85 dBA at all mills. The dosimetry and area noise measurements assigned to individual subjects generally showed good agreement, but for some operations within mill, large differences between the two measures were observed, and a substantial fraction of paired measures differed by >5 dB. Perceived noise exposures varied greatly between the mills, particularly for an item related to difficulty speaking in noise. One perceived noise exposure item related to difficulty hearing due to noise showed strong and significant correlations with both dosimetry and area measurements. The Method of Triads analysis showed that dosimetry measures had the highest estimated validity coefficient (0.70), and that the best performing perceived exposure measure had validity that exceeded that of area measurements (0.48 versus 0.40, respectively).\u0000\u0000\u0000CONCLUSIONS\u0000Workers in Swedish pulp mills have the potential for exposures to high levels of noise. Our results suggest that, while dosimetry remains the preferred approach to exposure assessment, perceived noise exposures can be used to evaluate potential exposures to noise in epidemiological studies.","PeriodicalId":342592,"journal":{"name":"The Annals of occupational hygiene","volume":"6 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132432600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}