Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Toxicol Ind Health ; 40(7): 353-365, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38662893

RESUMO

Exposure to heavy metals can result in various adverse health effects. Tehran is rated as one of the world's most polluted cities. Green space workers are continuously exposed to such pollutants in this city. Thus, this study aimed to estimate the health risks caused by exposure to heavy metals among green space workers. Eighty-eight workers and office personnel in two regions with different air quality levels were chosen for sampling. Air samples were collected using the NIOSH-7300 method and analyzed using an Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) instrument. The hazard quotient (HQ) and the lifetime cancer risk (LTCR) were calculated to assess carcinogenic and non-carcinogenic risk levels. The results revealed that the rank order of heavy metals was determined as Zn, Pb, Mn, Ni, Co, and Cd. Workers were subjected to higher concentrations of Ni, Pb, Zn, and Co than office personnel. Furthermore, the Cd, Co, and Zn exposure levels stood significantly higher in region 6 than in region 14. Non-carcinogenic risk levels for all participants fell within the acceptable range. Moreover, no employee had a carcinogenic risk level within the acceptable range when exposed to Cd. Also, 2.3% of individuals demonstrated Ni's acceptable carcinogenic risk level. Owing unacceptable risk levels, proper interventions are required to minimize occupational exposure to heavy metals. These interventions include optimizing shift schedules, using personal protective equipment, and conducting regular health assessments.


Assuntos
Metais Pesados , Exposição Ocupacional , Humanos , Irã (Geográfico) , Exposição Ocupacional/análise , Exposição Ocupacional/efeitos adversos , Metais Pesados/análise , Medição de Risco , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Adulto Jovem
2.
Med J Islam Repub Iran ; 33: 93, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31696087

RESUMO

Background: There are many factors related to etiology of metabolic syndrome (MetS) including obesity. Spexin, a peptide hormone released from adipose tissue, is the most down-regulated gene in obese, compared to non-obese adipose tissue. Hence, it potentially contributes to the progression and development of metabolic diseases. This study was designed to evaluate serum concentration of spexin in patients with MetS compared to weight-matched and normal-weight controls. Methods: In this case-control study, 153 participants (51 per group) were collected from October 2014 to June 2016. The study groups were all matched for age and sex and included overweight/obese individuals with MetS and 2 control groups without MetS (including weight-matched and normal-weight participants). Body composition and serum concentration of spexin and leptin were measured. Results: Serum leptin and spexin levels were significantly higher and lower, respectively, in normal-weight compared to overweight/obese groups with/without MetS (p< 0.02). No significant difference was observed in serum leptin and spexin concentrations between the overweight/obese groups with/without MetS (p≥ 0.05). Also, spexin, with cutoff value of 4.6, had 78% sensitivity and 82% specificity for diagnosing overweight/obese from normal-weight participants. Spexin had 78% sensitivity and specificity, with cutoff value of 4.35, in diagnosing MetS participants from normal-weight group. Conclusion: This study found no correlation between the circulating level of spexin and MetS development. Higher serum concentration of spexin in normal-weight adults compared to the obese participants illustrated the potential role of this novel peptide in obesity.

3.
J Vector Borne Dis ; 54(4): 353-357, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29460866

RESUMO

BACKGROUND & OBJECTIVES: Crimean-Congo haemorrhagic fever virus (CCHFV) causes severe disease with fatality rate of 30%. The virus is transmitted to humans through the bite of an infected tick, direct contact with the products of infected livestock as well as nosocomially. The disease occurs sporadically throughout many of African, Asian and European countries. Different species of ticks serve either as vector or reservoir for CCHFV. This study was aimed to determine the prevalence of CCHFV in hard ticks (Ixodidae) in the Golestan Province of Iran. METHODS: A molecular survey was conducted on hard ticks (Ixodidae) isolated from six counties in Golestan Province, north of Iran during 2014-15. The ticks were identified using morphological characteristics and presence of CCHFV RNA was detected using RT-PCR. RESULTS: Data revealed the presence of CCHFV in 5.3% of the ticks selected for screening. The infected ticks belonged to Hyalomma dromedarii, Hy. anatolicum, Hy. marginatum and Rhipicephalus sanguineus species. INTERPRETATION & CONCLUSION: The study demonstrated that Hyalomma ticks are the main vectors of CCHFV in Golestan Province. Thus, preventive strategies such as using acaricides and repellents in order to avoid contact with Hyalomma ticks are proposed.


Assuntos
Reservatórios de Doenças/virologia , Vetores de Doenças , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Febre Hemorrágica da Crimeia/epidemiologia , Ixodidae/virologia , Animais , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/prevenção & controle , Febre Hemorrágica da Crimeia/virologia , Humanos , Irã (Geográfico)/epidemiologia , Ixodidae/classificação , Filogenia , Prevalência , RNA Viral/genética
4.
Noise Health ; 19(89): 200-206, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28816207

RESUMO

INTRODUCTION: Noise exposure may have anatomical, nonauditory, and auditory influences. Considering nonauditory impacts, noise exposure can cause alterations in the automatic nervous system, including increased pulse rates, heightened blood pressure, and abnormal secretion of hormones. The present study aimed at examining the effect of various sound pressure levels (SPLs) on the serum aldosterone level among rats. MATERIALS AND METHODS: A total of 45 adult male rats with an age range of 3 to 4 months and a weight of 200 ± 50 g were randomly divided into 15 groups of three. Three groups were considered as the control groups and the rest (i.e., 12 groups) as the case groups. Rats of the case groups were exposed to SPLs of 85, 95, and 105 dBA. White noise was used as the noise to which the rats were exposed. To measure the level of rats' serum aldosterone, 3 mL of each rat's sample blood was directly taken from the heart of anesthetized animals by using syringes. The taken blood samples were put in labeled test tubes that contained anticoagulant Ethylenediaminetetraacetic acid. In the laboratory, the level of aldosterone was assessed through Enzyme-linked immunosorbent assay protocol. The collected data were analyzed by the use of Statistical Package for Social Sciences (SPSS) version 18. RESULTS: The results revealed that there was no significant change in the level of rats' serum aldosterone as a result of exposure to SPLs of 65, 85, and 95 dBA. However, the level of serum aldosterone experienced a remarkable increase after exposure to the SPL of 105 dBA (P < 0.001). Thus, the SPL had a significant impact on the serum aldosterone level (P < 0.001). In contrast, the exposure time and the level of potassium in the used water did not have any measurable influence on the level of serum aldosterone (P = 0.25 and 0.39). CONCLUSION: The findings of this study demonstrated that serum aldosterone can be used as a biomarker in the face of sound exposure.


Assuntos
Aldosterona/sangue , Exposição Ambiental/efeitos adversos , Som/efeitos adversos , Estimulação Acústica/métodos , Animais , Masculino , Ruído/efeitos adversos , Pressão , Ratos
5.
Noise Health ; 18(85): 391-398, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27991472

RESUMO

INTRODUCTION: Noise is considered as the most common cause of harmful physical effects in the workplace. A sound that is generated from within the inner ear is known as an otoacoustic emission (OAE). Distortion-product otoacoustic emissions (DPOAEs) assess evoked emission and hearing capacity. The aim of this study was to assess the signal-to-noise ratio in different frequencies and at different times of the shift work in workers exposed to various levels of noise. It was also aimed to provide a statistical model for signal-to-noise ratio (SNR) of OAEs in different frequencies based on the two variables of sound pressure level (SPL) and exposure time. MATERIALS AND METHODS: This case-control study was conducted on 45 workers during autumn 2014. The workers were divided into three groups based on the level of noise exposure. The SNR was measured in frequencies of 1000, 2000, 3000, 4000, and 6000 Hz in both ears, and in three different time intervals during the shift work. According to the inclusion criterion, SNR of 6 dB or greater was included in the study. The analysis was performed using repeated measurements of analysis of variance, spearman correlation coefficient, and paired samples t-test. RESULTS: The results showed that there was no statistically significant difference between the three exposed groups in terms of the mean values of SNR (P > 0.05). Only in signal pressure levels of 88 dBA with an interval time of 10:30-11:00 AM, there was a statistically significant difference between the right and left ears with the mean SNR values of 3000 frequency (P = 0.038). The SPL had a significant effect on the SNR in both the right and left ears (P = 0.023, P = 0.041). The effect of the duration of measurement on the SNR was statistically significant in both the right and left ears (P = 0.027, P < 0.001). CONCLUSION: The findings of this study demonstrated that after noise exposure during the shift, SNR of OAEs reduced from the beginning to the end of the shift.


Assuntos
Perda Auditiva Provocada por Ruído/fisiopatologia , Ruído Ocupacional , Doenças Profissionais/fisiopatologia , Exposição Ocupacional , Emissões Otoacústicas Espontâneas , Razão Sinal-Ruído , Adulto , Estudos de Casos e Controles , Humanos , Irã (Geográfico) , Masculino , Fatores de Tempo
6.
Noise Health ; 18(80): 1-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26780955

RESUMO

The existing literature indicates that occupational exposure to noise may have adverse effects on workers' health. The aim of this study was to evaluate the possible effects of exposure to different sound pressure levels (SPLs) on serum aldosterone and potassium concentration among Iranian blue collar workers in Golgohar Mining and Industrial Company in Sirjan, Kerman Province, Iran. This case-control study was performed on 45 workers of Golgohar Mining and Industrial Company. The subjects consisted of 30 workers from manufacturing departments and 15 office employees of the mining company. The controls, mainly with administrative jobs were exposed to 72 dBA SPL. Cases, in two separate groups, were exposed to noise levels of 88 dBA and 103 dBA, respectively. Noise intensity was measured at the desired locations. Noise measurements were performed according to the International Organization for Standardization (ISO) 9612. To measure the serum aldosterone and potassium concentrations, a 5 mL blood sample was taken from each worker at the specified time intervals and aldosterone concentration was determined using enzyme-linked immunosorbent assay (ELISA) test in the laboratory. Repeated measurement and Spearman's correlation coefficient analysis were used with α = 0.05. Exposure to the different levels of sound pressure resulted in different aldosterone concentrations and meanwhile an increase in the SPL did not affect the concentration of potassium. From 10:00 AM to 10:30 AM, as SPL increased, aldosterone concentrations did not increase significantly but from 13:30 PM to 14:00 PM, raised SPL led to a significant increase in aldosterone concentration. However, there was no correlation between the concentration of potassium and different factors. This study indicated that increases in SPLs affect aldosterone concentration but at the same time do not have significant effects on serum potassium level.


Assuntos
Aldosterona/sangue , Mineração , Ruído Ocupacional/efeitos adversos , Potássio/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Perda Auditiva Provocada por Ruído/etiologia , Humanos , Irã (Geográfico)
7.
Med J Islam Repub Iran ; 29: 204, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26157722

RESUMO

BACKGROUND: Adolescence is a sensitive period of acquiring normal and abnormal habits for all oflife. The study investigates determinants of responsibility for health, spiritual health and interpersonal relations and predictive factors based on the theory of planned behavior in high school girl students in Tabriz. METHODS: In this Cross-sectional study, 340 students were selected thorough multi-stage sampling. An author-made questionnaire based on standard questionnaires of Health Promotion and Lifestyle II (HPLPII), spiritual health standards (Palutzian & Ellison) and components of the theory of planned behavior (attitudes, subjective norms, perceived behavioral control, and behavioral intention) was used for data collection. The questionnaire was validated in a pilot study. Data were analyzed using SPSS v.15 and descriptive and analytical tests (Chi-square test, Pearson correlation co-efficient and liner regression test in backward method). RESULTS: Students' responsibility for health, spiritual health, interpersonal relationships, and concepts of theory of planned behavior was moderate. We found a significant positive correlation (p<0/001) among all concepts of theory of planned behavior. Attitude and perceived behavioral control predicted 35% of intention of behavioral change (p<0.001). Attitude, subjective norms, and perceived behavioral control predicted 74% of behavioral change in accountability for health (p<0.0001), 56% for behavioral change in spiritual health (p<0.0001) and 63% for behavioral change in interpersonal relationship (p<0.0001). CONCLUSION: Status of responsibility for health, spiritual health and interpersonal relationships of students was moderate. Hence, behavioral intention and its determinants such as perceived behavioral control should be noted in promoting intervention programs.

8.
Vector Borne Zoonotic Dis ; 24(3): 159-165, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38016137

RESUMO

Background: Phlebotomus papatasi (Diptera: Psychodidae) is the main vector of zoonotic cutaneous leishmaniasis. Wolbachia is a symbiotic alphaproteobacteria of arthropods that can be involved in susceptibility or resistance. This study aimed to investigate the relationship between Wolbachia and Deltamethrin susceptibility/resistance in Ph. papatasi. Deltamethrin filter papers (0.00002%) were used to test sand fly field collected from southern Iran. After the test, PCR amplification of the Wolbachia surface protein gene (wsp) was used to measure Wolbachia infection rate in the killed, surviving, and control groups. Result: The rates of infection by Wolbachia strain (wPap, super group A) differed between killed (susceptible) and surviving (resistant) Ph. papatasi specimens. The rate of Wolbachia infection in susceptible individuals was more than twice (2.3) (39% vs. 17%) in resistant individuals with the same genetic background. This difference was highly significant (p < 0.001), indicating a positive association between Wolbachia infection and susceptibility to Deltamethrin. In addition, the results showed that Deltamethrin can act as a PCR inhibitor during detection of Wolbachia in Ph. papatasi. Conclusion: Results of this study show that Wolbachia is associated with Deltamethrin susceptibility level in Ph. papatasi. Also, as Deltamethrin has been identified as a PCR inhibitor, great care must be taken in interpreting Wolbachia infection status in infected populations. The results of this study may provide information for a better understanding of the host-symbiont relationship, as well as application of host symbiosis in pest management.


Assuntos
Inseticidas , Leishmaniose Cutânea , Nitrilas , Phlebotomus , Psychodidae , Piretrinas , Wolbachia , Animais , Humanos , Phlebotomus/microbiologia , Inseticidas/farmacologia , Wolbachia/genética , Leishmaniose Cutânea/veterinária
9.
Parasit Vectors ; 16(1): 284, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580774

RESUMO

BACKGROUND: The time required for PCR detection of DNA in human blood meals in vector mosquitoes may vary, depending on the molecular markers used, based on the size and copy number of the amplicons. Detailed knowledge of the blood-feeding behavior of mosquito populations in nature is an essential component for evaluating their vectorial capacity and for assessing the roles of individual vertebrates as potential hosts involved in the transmission of vector-borne diseases. METHODS: Laboratory experiments were conducted to compare the time course of PCR detection of DNA in human blood meals from individual blood-fed Anopheles stephensi mosquitoes, using loci with different characteristics, including two mitochondrial DNA (mtDNA) genes, cytB (228 bp) and 16S ribosomal RNA (rRNA) (157 bp) and nuclear Alu-repeat elements (226 bp) at different time points after the blood meal. RESULTS: Human DNA was detectable up to 84-120 h post-blood-feeding, depending on the length and copy number of the loci. Our results suggest that 16S rRNA and Alu-repeat markers can be successfully recovered from human DNA up to 5 days post-blood-meal. The 16S rDNA and Alu-repeat loci have a significantly (P = 0.008) slower decline rate than the cytB locus. Median detection periods (T50) for the amplicons were 117, 113 and 86.4 h for Alu-repeat, 16S rDNA and cytB, respectively, suggesting an inverse linear relationship between amplicon size/copy number and digestion time. CONCLUSION: This comparative study shows that the Alu-repeat locus is the most efficient marker for time-course identification of human DNA from blood meals in female mosquitoes. It is also a promising tool for determining the anthropophilic index (AI) or human blood index (HBI), i.e. the proportion of blood meals from humans, which is often reported as a relative measure of anthropophagy of different mosquito vectors, and hence a measure of the vector competence of mosquito species collected in the field.


Assuntos
Anopheles , Animais , Humanos , Feminino , Anopheles/genética , Genes Mitocondriais , RNA Ribossômico 16S/genética , Elementos Alu/genética , Mosquitos Vetores , DNA Mitocondrial/genética , DNA Ribossômico , Refeições , Comportamento Alimentar
10.
Sci Rep ; 13(1): 14912, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689736

RESUMO

Vector-borne diseases, among them leishmaniasis, cause more than 700,000 deaths annually. The lack of an effective vaccination and the increasing resistance of sand flies to insecticides require the urgent development of innovative approaches to contain the disease. The use of engineered bacteria that express anti-parasite molecules (paratransgenesis) shows much promise. However, a challenge for implementation of this strategy is to devise means to introduce modified bacteria into sand flies in the field. In this study, we use rodent food bait as a delivery strategy to introduce two mCherry-fluorescent bacteria, Serratia AS1 and Enterobacter cloacae, into adult sand flies in field settings. Bacteria-infected food was provided to Rhombomys opimus rodents. These bacteria transiently pass through the rodent alimentary tract and are delivered to larval habitats with the rodent feces. The feces are ingested by sand fly larvae and, in the case of Serratia AS1, are trans-stadially transmitted to adults. This is the first report of targeting delivery of Serratia AS1 in a paratransgenic system to control transmission of leishmaniasis under field condition. This novel strategy shows promise for delivering transgenic bacteria to Leishmania vectors in the field.

11.
Ann Med Surg (Lond) ; 85(5): 1678-1684, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37229071

RESUMO

Studies on coronavirus disease 2019 (COVID-19) symptoms, post-coronavirus disease (COVID) conditions, and vaccination outcomes in Pakistan are limited and inconsistent. The study investigated differences in symptoms and post-COVID conditions between vaccinated and unvaccinated individuals and the impact of vaccination on illness duration based on existing literature. Methods: The study was a 3-month cross-sectional study conducted in Peshawar, Pakistan. It targeted individuals aged 16 and above who had contracted COVID-19 at least once during the recent pandemic, regardless of gender, and confirmed through reverse transcriptase polymerase chain reaction testing. The sample size was 250, determined using the WHO sample size calculator. Data were collected through questionnaires after obtaining verbal consent and analyzed using IBM SPSS version 26, taking into account their vaccination status along with other important variables. Results: Among the 250 respondents, 143 (57.2%) were unvaccinated, while 107 (42.8%) were vaccinated at the time of contracting COVID-19. Unvaccinated subjects developed a greater variety of symptoms that lasted for longer durations (P<0.001) with symptoms like dyspnea [55 (38.5%, P=0.011)], anosmia [76 (53.1%, P=0.001)], and chest pain [24 (16.8%, P=0.029)] occurring at greater percentages. Sixty-one (42.7%) unvaccinated subjects reported post-COVID conditions as opposed to 29 (27.1%) among the vaccinated group [P=0.011; odds ratio (OR)=0.5; 95% CI=0.29-0.86]. Conclusion: The study found that COVID-19 vaccination can reduce the duration and frequency of symptoms, as well as post-COVID conditions. This is the first research of its kind conducted in Peshawar, Pakistan, and may serve as a foundation for future research in this demographic.

12.
Sleep Biol Rhythms ; 20(2): 275-285, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38469258

RESUMO

Driver's drowsiness is one of the high-risk road behaviors that quadruples the risk of road accidents. Measures to deal with drowsiness during driving include listening to music. The present study investigates the effect of two types of music, namely Iranian high-tempo pop and classical music, on mental and physiological drowsiness during driving. Twelve male students at Tehran University of Medical Sciences within the normal range of the Epworth Drowsiness Scale (ESS) participated in this study. Two types of music (classical and pop) were assessed on two separate days with an interval of one week. The mental aspect of drowsiness was evaluated using the Karolinska Sleepiness Scale (KSS), the physiological aspect by monitoring the EEG and heart rate, and the functional aspect through the mean and standard deviation of speed and the Standard Deviation of Lateral Position (SDLP) in a driving simulator. The results showed that the brain waves (four algorithms (1) (θ + α)/ß, (2) α/ß, (3) (θ + α)/(α + ß) and (4) θ/ß), the KSS score, SDLP and standard deviation of speed all decrease while the mean heart rate increases when listening to music during driving compared to driving without music. No significant difference was observed in the mean speed when exposed to music. Moreover, no difference was observed between the effect of the two music styles, i.e. Iranian classical and pop music. Listening to Iranian classical and pop music while driving improves the driver's performance and reduces drowsiness. The present study showed that higher tempo music during driving can reduce drowsiness and change physiological responses and driving performance.

13.
Regul Toxicol Pharmacol ; 60(2): 200-5, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21420461

RESUMO

Iran imports nearly 55,000 metric tons of asbestos per year, and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, asbestos fiber concentrations during AC sheet and pipe manufacturing were measured by phase-contrast microscopy (PCM) and polarized light microscopy (PLM) in 98 personal air samples. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). Personal monitoring of fiber levels indicated a range from 0.02 to 0.55PCM f/ml (0.02-0.69PLM f/ml). The AC workers' geometric mean asbestos exposure was 0.09 PCM f/ml (0.11 PLM f/ml), with arithmetic mean of 0.13 PCM f/ml (0.16 PLM f/ml). The observed fiber concentrations in many processes were higher than the threshold limit value (TLV) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH), which is 0.1 f/ml. Based on these findings, the PLM values were approximately 25% higher than PCM values. The SEM data demonstrate that fibrous particles contained chrysotile. The thinnest fiber recognized by SEM had a diameter of 0.2µm. Mean exposure exceeded the TLV for asbestos in pipe molding and finishing (100%) as well as sheet molding and finishing (45.5-83.3%). In conclusion exposure control may be needed to be in compliance with the ACGIH TLV and other guidance levels. Also, with regard to PCM limitations for airborne fiber analysis, the use of microscopic methods other than PCM can be used to improve the techniques used presently.


Assuntos
Poluentes Ocupacionais do Ar/análise , Amianto/análise , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Amianto/química , Asbestos Serpentinas/análise , Asbestos Serpentinas/química , Humanos , Indústrias , Irã (Geográfico) , Microscopia/métodos , Microscopia Eletrônica de Varredura/métodos , Fibras Minerais/análise
14.
Int J Occup Saf Ergon ; 27(3): 654-663, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31538862

RESUMO

Purpose. The probability of being injured or killed from an occupational incident is much higher than a process mishap in the oil and gas industry. The aim of this study was to establish a model for predicting the probability of occupational fall incidents using Bayesian networks. Methods. The study was performed in a selected number of oil refineries. Bayesian network variables (n = 18) were identified using literature as well as expert knowledge. These contributing factors were categorized into four layers (organizational, supervisory, preconditions and unsafe acts) according to the Swiss cheese model. Causal relationships among contributing factors were determined using expert judgment in combination with Dempster-Shafer theory. The conditional probability table of each contributing factor was measured using a questionnaire. Results. The prior probability of fall events was 5.34% (53 cases per 1000 operational workers in 12 months). The posterior probability predicted that using fall protection devices and safe working platforms will decrease more than half (58%) of fall occupational incidents. Conclusion. Bayesian network features including graphical representation, easy belief updating, performance testing and sensitivity analysis facilitate the process of predicting occupational incident probability including fall events. The proposed approach is a step toward quantitative risk analysis of occupational incidents.


Assuntos
Indústrias , Teorema de Bayes , Humanos , Probabilidade , Medição de Risco , Inquéritos e Questionários
15.
Artigo em Inglês | MEDLINE | ID: mdl-33807782

RESUMO

Previous studies have demonstrated that a positive ergonomics climate with an equal focus on improving operational performance and employee well-being is beneficial to both employee health and organizational performance. This study aimed to assess the ergonomics climate at two power plants and examine its association with self-reported pain, performance, and well-being. At two power plants in Iran, survey responses from 109 and 110 employees were obtained. The questionnaires contained data on ergonomics climate, organizational performance, employee health, and self-reported pain. Results showed that the mean ergonomics climate scores between the Besat and Rey power plants were significantly different (p < 0.001). The overall ergonomics climate score, and all subscales scores, were positively associated with organizational performance (p < 0.001). The overall ergonomics climate score, and some of its subscales, were significantly associated with employees' general health (p < 0.001). The ergonomics climate score was significantly higher in the group of employees who reported musculoskeletal pain than those who did not report musculoskeletal pain (p < 0.05). Investigation of ergonomics climate can provide organizations with a baseline for prioritizing their values and finding areas for improving organizational performance and employee health.


Assuntos
Ergonomia , Cultura Organizacional , Humanos , Irã (Geográfico)/epidemiologia , Dor , Autorrelato
16.
MethodsX ; 8: 101354, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430255

RESUMO

This paper aimed to fabricate UV protective nanofibers by the use of specific nanoparticles. The DMF/TiO2 (Titanium dioxide), DMF/MWCNT (Multi-Walled Carbon Nano Tubes), and DMF/MWCNT+TiO2 (MWCNT: TiO2 mass ratio= 1:1) solutions were transferred into a syringe with a stainless steel needle with gauge 21. The electrospinning process was performed for 3 h at the optimized conditions. The surface morphology of nanofibers was characterized by field emission scanning electron microscopy (FESEM). Fourier transform infrared spectroscopy (FTIR) was utilized to characterize functional groups of oxidized MWCNTs and investigate the successful load of nanoparticles at the fiber surface. The UV protection property of nanofibers was investigated by measuring UV rays' transmittance through the composite web. The data of Spectroscopy was used to compute the UV protection factor (UPF). (1) The effect of CNT,TiO2, and CNT+TiO2 nanoparticles on ultraviolet protection property was analyzed separately and simultaneously. (2) The different concentrations of nanoparticles, including 1,5,10, & 15 wt%, were used to fabricate UV protective nanocomposites. (3) The electrospinning condition was optimized as a 15 cm distance between the needle tip and collector, 20 KV voltage, 250 RPM drum rotation, and 1.2 ml/h feeding rate to access the best nanofibers.

17.
Work ; 68(3): 711-719, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33612515

RESUMO

BACKGROUND: The study aimed to assess the interactive effects of industrial noise type, level and frequency characteristics on hand motor skills using the Minnesota Manual Dexterity Test and the Hand Tool Dexterity Test. METHODS: A total of ten nonsmoking male volunteers with normal hearing and vision were selected for this study. The study followed a full 3×3×2 factorial design. Independent variables were noise type (steady, intermittent and fluctuating), noise level (75, 85 and 95 dBA) and frequency characteristics ("roar" <2000 Hz and "hiss" >2000 Hz). RESULTS: For Minnesota Manual Dexterity Test, the lowest speed is related to steady hiss noise at 75 dBA and the highest speed is related to fluctuating roar noise at 95 dBA. The speed is being significantly affected by the frequency characteristic (P = 0.041) and noise type (P = 0.025). The effect of hiss noise on speed is greater than roar noise (P = 0.038). There is a significant difference (P = 0.035) between continuous noise and fluctuating noise. For the Hand Tool Dexterity Test, the lowest speed is related to fluctuating hiss noise at 95 dBA and the highest speed is related to steady roar noise at 95 dBA. The speed is being significantly affected by the frequency characteristic (P = 0.002), noise type (P = 0.0001) and noise level (P = 0.005). The effect of hiss noise on response variable to be greater than roar noise (P = 0.008). There is a significant difference (P = 0.0001) between steady noise and the two other types of noise, and also there is a significant difference between 75 dBA and 85 dBA level (P = 0.003). CONCLUSIONS: The results showed that on hand motor skills, speed response was influenced by three characteristics: the type of noise, frequency characteristics and noise level. Also, the effect of the hiss noise was more than the roar noise.


Assuntos
Mãos , Destreza Motora , Humanos , Indústrias , Masculino , Minnesota , Ruído/efeitos adversos
18.
Iran J Public Health ; 50(8): 1668-1677, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34917538

RESUMO

BACKGROUND: Mosquito species are highly considering as disease transmission as well as nuisance insects. One of the principal strategy to protect human from the mosquito bites is repellent agents. This study aimed to assess repellency of two organic essential oils, Eucalyptus globulus and Syzygium aromaticum from bites of malaria vector, Anopheles stephensi. METHODS: The study was conducted in 2019-2020. The components of essential oils of E. globulus and S. aromaticum was determined using gas chromatography/mass spectrometry. The unfed female mosquitoes aged 2-5 d old were used in all experiments. In vivo Klun and Debboun module bioassays were utilized on human-volunteer skin. The essential oils at serial concentrations were used to find repellent efficacy against Anopheles landings and bites. To find the synergistic effect, four combinations of the essential oils were tested. RESULTS: The main composition of E. globulus essential oil was 1,8-Cineol (78.20%), whereas that of S. aromaticum essential oil was 2-methoxy-3-(2-propenyl) (77.04%). Based on minimum effective dose (≤1% biting), 10% (v/v) of E. globulus showed high landing repellency (77.78%), whereas minimum effective dose of S. aromaticum at concentration of 1% had high landing repellency (88.89%). Among four combinations, the ratio of 1:1 of E. globulus (10%):S. aromaticum (1%) showed the most landing repellency (94.44%). CONCLUSION: The combinations of two essential oils had the most potential repellency effect against landing of mosquitoes. As essential oils are eco-friendly with less irritation for human skin, E. globulus and S. aromaticum essential oils are recommended as effective and safe mosquito repellents.

19.
Sci Justice ; 61(3): 227-234, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33985671

RESUMO

Entomological material may be used to estimate the time since death occurred (postmortem interval, PMI) in forensically obscure cases. The method that is commonly used to calculate minimum post-mortem interval (mPMI, i.e., the least amount of time since one can be confident death occurred) is based on the relationship between insect development and ambient temerature. Isomegalen and isomorphen diagrams are among methods allowing to calculate the age of necorphagous insects, yet thermal summation models provide the most precise and acurate estimations. The digrams are prepared based on the length or the developmental stages of the larvae as a function of time and mean ambient temperature. A knowledge of thermal requirements, in particular lower temperature threshold (Dz) at which development of a species terminates, is of essential importance to calculate ADD (Accumulated Degree Days). In this study different temperature regimes were used to construct the isomorphen diagram, examinate changes in larval body length at different ambient temperatures and to estimate the thermal requirements for developemnt of Chrysomya albiceps, the most common dipteran species reported on human and animal cadavers in Iran. Six development events including hatching, 1st ecdysis, 2nd ecdysis, wandering, pupariation and eclosion were studied under eleven constant temperature regims (17-37 0C). The development rate of Ch. albiceps increased as temperature increased. The larval length peaked at the end of third stage and then decreased at wandering stage. The maximum larval length occurred at 72 h post oviposition at either 31, 33, or 35 °C. At 17 °C, larvae did not hatch from eggs and at 37 °C wandering larvae did not proceed to pupariation, and thus larval development were analysed at the nine left over temperatures. The development stages required at least (Dz ± SE) 13.04 ± 0.37, 14.29 ± 0.45, 15.69 ± 0.56, 15.18 ± 0.56, 14.94 ± 0.48, and 11.23 ± 0.41 °C to reach one of the successive developmentl events, respectively. The estimated thermal summation constant (k) for those the six events were 10.43 ± 0.27, 19.31 ± 0.32, 27.87 ± 1.3, 55.94 ± 1.82, 66.69 ± 3.5, and 143.52 ± 5.61 ADD accordingly.


Assuntos
Dípteros , Animais , Calliphoridae , Entomologia , Humanos , Larva , Temperatura
20.
J Cardiovasc Thorac Res ; 12(1): 27-34, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32211135

RESUMO

Introduction: Limited data are available on the association of Dietary Inflammatory Index (DII) with metabolic syndrome (MetS) and its components. The present study was conducted to investigate the association of DII with MetS and its components among Iranian adults. Methods: A total of 404 subjects, aged 18 years or older, were included in the current cross-sectional study. We used a validated and reliable 147-item food frequency questionnaire (FFQ) to assess dietary intakes. Fasting blood sample was obtained to quantify glycemic indicators and lipid profile. MetS was defined based on the guidelines of the National Cholesterol Education Program Adult Treatment Panel III (ATP III). Results: Mean age of study participants was 38.20 ± 9.55 years. No significant association was found between DII and odds of MetS (odds ratio [OR]: 0.92, 95% CI: 0.48-1.76). In terms of MetS components, a significant positive association was seen between DII scores and reduced levels of high-density lipoprotein cholesterol (HDL-C) (OR: 2.29, 95% CI: 1.32-3.97); such that after controlling for energy intake, demographic variables and BMI, participants in the highest category of DII had 2.71 times greater odds for having reduced levels of HDL-C (OR: 2.71, 95% CIs: 1.34, 5.47). There was no other significant association between other components of MetS and DII scores either before or after adjusting for confounding variables. Conclusion: We observed no significant association between DII and odds of MetS. However, higher score of DII was associated with lower levels of HDL.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA