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BACKGROUND: Paddy milling is the oldest and largest agro-processing industry in India. A large number of workers are employed in the rice mills where they are potentially exposed to dust. It has been shown that exposure to dust results in a high prevalence of respiratory diseases, such as asthma, chronic bronchitis, extrinsic allergic alveoli ties, toxic syndrome, and interstitial lung disease. OBJECTIVE: The aim of this study was to investigate the effect of dust on rice mill workers' health using lung function tests with comparison to an unexposed population. PARTICIPANTS: Two hundred eighteen rice mill workers (exposed volunteers) were randomly selected from 25 rice mills in Assam, India. Participants were 18-60 years with at least one year of work experience. Further, 377 volunteers who were not exposed to dust and having similar demographic characteristics also participated as a control group. METHOD: Pulmonary function tests were conducted for all participants by spirometry. The tests included forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC (%), peak expiratory flow (PEF) and forced expiratory flow during the middle half of a forced vital capacity (FEF25-75%). Values from exposed workers were compared with the unexposed volunteers. RESULTS: It was observed that the lung function parameters FVC, FEV1, PEF and FEF25-75% in exposed workers were significantly decreased compared with unexposed volunteers. There were also significantly decreased FVC, FEV1, FEV1/FVC%, PEF and FEF25-75% with increase in age and duration of dust exposure. It was further observed that 48% and 32% of the total male and female volunteers, respectively, had evidence of lung disease. Irrespective of gender, approximately 45% of mill workers had evidence of lung disease, of which 21% was restrictive and 24% was obstructive. CONCLUSION: Compared with unexposed controls, rice mill workers have a greater prevalence of respiratory disease based on pulmonary function tests.

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Objectives. Given the burgeoning impacts of climatic variability on human health, suitable computational paradigms are used to explore the subsequent ergonomic repercussions. The artificial neural network (ANN), in particular, exhibits near-accurate input-output mapping. However, employment of the ANN to trace the inter-dependencies between the climatic and human thermoregulatory parameters in real-world fuzzy problem landscapes is relatively inadequate. In the present study, the ANN models examined the relationships between climatic, behavioral and intrinsic input factors and the thermoregulatory outputs, namely, sweating and the evaporative heat transfer at the skin surface (Esk). Methods. The data were obtained from nearly 1800 subjects who were exposed to a hot and humid climate outdoors. The ANN models were trained using the Levenberg-Marquardt algorithm combined with Bayesian regularization. Results. The predictability of the ANN models was statistically substantiated. The clothing insulation factor was not included as an input parameter, given its similar values. Intriguingly, the ANN results indicated that fabrics with similar thermal resistances could still affect Esk, plausibly owing to the temporal variation in the evaporative resistance of fabrics among individuals. Conclusion. The reasonably accurate results affirmed the suitability of ANN as a pragmatic technique that could elucidate heat-induced ergonomic challenges.

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Bulk-surface correspondence in Weyl semimetals ensures the formation of topological "Fermi arc" surface bands whose existence is guaranteed by bulk Weyl nodes. By investigating three distinct surface terminations of the ferromagnetic semimetal Co3Sn2S2, we verify spectroscopically its classification as a time-reversal symmetry-broken Weyl semimetal. We show that the distinct surface potentials imposed by three different terminations modify the Fermi-arc contour and Weyl node connectivity. On the tin (Sn) surface, we identify intra-Brillouin zone Weyl node connectivity of Fermi arcs, whereas on cobalt (Co) termination, the connectivity is across adjacent Brillouin zones. On the sulfur (S) surface, Fermi arcs overlap with nontopological bulk and surface states. We thus resolve both topologically protected and nonprotected electronic properties of a Weyl semimetal.

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A cross-sectional study examined the human susceptibility of a sample farmworker (N = 1144) in eastern India, who were exposed to the tropical hot outdoor environment during paddy and potato cropping activities (November to April). The study explored the efficacy of human thermal indices in human susceptibility categorization, based on analysis of indices, such as WBGT, HI, Humidex, UTCI, PET, SET*, PMV, and objective and subjective responses to heat-related symptoms and disorders. Analysis indicated dissimilarities in the estimated temperature levels of indices, attributed to different numerical weights of the meteorological and behavioural parameters. Therefore, the study explored the thermal stress level identified by different indices. December and January were recognized the comfortable months by most of the thermal indices. March and April were strong to very strong heat stress, with exception noted for SET*. In comparison to rational indices, the Esk, a thermoregulatory parameter, signified the relative change in the evaporative exchange with the increasing environmental warmth. The defined level of Esk at ~200 W/sq·m corresponded to the comfortable temperature range within 19.5 to 22.5 °C for WBGT, PET, and Ta. Beyond this specific range of warmth, a proportionate increase in Esk would result in cumulative heat-related symptoms of stress and strain. The study noted a sizeable number of farmworkers manifested moderate to high intensity of heat-related symptoms, with a relatively higher percentage in case of females. The principal component analysis yielded three principal components of heat-related responses, labeled as (a) physical fatigue and responses, (b) neural stressors, and (c) behavioural effects. Normalized component scores transformed into a generalized quantitative climatic susceptibility indicator may be applied to the moderate intensity of physical activity in the tropical hot and humid environment.

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The farmers in tropical climate are exposed to high heat during the summer months. The study examined the physiological strains of farmers (N=26) to six combined exposures of work and high heat, with moderate and heavy work (26 to 50%, and 51 to 75% VO(2max)) and three ambient conditions, i.e., 34.4 to 42.2 degrees C WBGT (inside) in an environmental chamber. While the cardio-respiratory responses and Tcr were predominantly influenced by the work severity (p<0.001), the environmental warmth greatly influenced the sweating response (p<0.001). The importance was placed on the segmental Tsk as the first rank indicator of the bodily heat strain. Both the environmental warmth and work severity had independent discernable effects on the dynamic equilibrium of the central and peripheral mechanism to regulate the body temperature. The segmental and compartmental (core, muscle, fat and skin) heat balance analysis indicated the span of convergence of the segmental core and muscle temperatures to the divergence of skin and fat temperatures (CORE-SHELL) as a quantitative estimate of the segmental gradient for heat transfer. The summation of heat exchange across the compartments and segments yielded the transient change in Tcr (0.06 to 0.12 degrees C/min), with significant difference between the moderate and heavy work. The Tcr of 39 degrees C was taken as the limit of tolerance for the farmers, and by defining the criteria limit of Tcr of approximately 2.5 degrees C gradient from the basal Tcr and the rate of change in Tcr, the tolerance times were estimated. Corollary to the development of ISO 7933 standard (PHS index), the predictions of tolerance times from the transient change in Tcr or the exponential relationship with the WBGT (tolerance time, min = 1,841 e (-0.103 WBGT)) were useful to suggest the protective limit for men at work in extremely hot environment. The simplicity of prediction lies in using WBGT as a criterion. The exponential equation estimated the tolerance time of 55 min at 34 degrees C WBGT, and up to 38 degrees C WBGT, the decrease in tolerance time was 4 to 5 min per degree increase in environmental warmth. Beyond 38 degrees C WBGT, the estimated tolerance time decreased by 2 to 3 min per degree increase in WBGT. Further optimization and validation of the knowledge for men and women farmers in different age groups will have application in managing heat illnesses and disorders in tropical farming.

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A cross sectional survey was initiated to understand the frequency of occupational injury occurrence and the associated factors in the fish processing industries of western India involving 185 randomly selected women subjects. All the subjects were interviewed with the help of an interviewer-administered questionnaire to collect information regarding their personal, occupational and work related morbidity details (including details of occupational injuries). Logistic regression method was used to analyze the data in order to obtain the contribution of individual factors on occupational injuries. This study has shown that work related morbidity like blanching of hand (OR; 2.30, 95%CI; 1.12-4.74) and nature of job like grading (OR; 3.99, 95%CI; 1.41-11.27) and packing (OR; 5.68, 95%CI; 1.65-19.57) had a significant impact on injury causation. This study eventually concludes that apart from nature of job of fish processing workers occupational hazards prevailing in the work environment contribute significantly to the occurrence of work related injuries and prevention of such occupational hazards may help in protecting workers from occupational injuries also.

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The Indian farming employs 225 million workforce to cover 140 million hectares of total cultivated land. In spite of rapid farm mechanization (e.g., 149 million farm machinery), the vast resource-poor family farming has primary dependence on traditional methods (e.g., 520 million hand tools and 37 million animal-drawn implements are in operation). The work drudgery, the traumatic accidents and injuries are the major concerns to examine options for ergonomics intervention and betterment of work in crop production activities. This review summarizes human energy expenditure in crop production activities, to assess the job severity, tools and machinery, and formulate the basis to reorganize work and work methods. While the farm mechanization is more in the northern India, the accidents were more in the villages in southern India. On average of the four regions, the tractor incidents (overturning, falling from the tractor, etc.) were highest (27.7%), followed by thresher (14.6%), sprayer/duster (12.2%), sugarcane crusher (8.1%) and chaff cutter (7.8%) accidents. Most of the fatal accidents resulted from the powered machinery, with the annual fatality rate estimated as 22 per 100,000 farmers. The hand tools related injuries (8% of the total accidents) were non-fatal in nature. In spite of the enactment of legislation, the shortcomings in production and monitoring of the machinery in field use may be responsible for the high rate of accidents (e.g., 42 thresher accidents/1,000 mechanical threshers/year in southern India). Due to the lack of technical capability of the local artisans, adhering to safety and design standards is impractical to the implements fabricated in the rural areas. The analysis emphasizes that the effective safety and health management may be possible through legislative enabling of the local infra-structure, such as block development authority and primary health services, to permeate occupational health and safe work practices in the farming sector.

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