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1.
ACS Appl Mater Interfaces ; 16(22): 28938-28948, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38780164

ABSTRACT

In the domain of organic mixed ionic-electronic conductors (OMIECs), simultaneous transport and coupling of ionic and electronic charges are crucial for the function of electrochemical devices in organic electronics. Understanding conduction mechanisms and chemical reactions in operational devices is pivotal for performance enhancement and is necessary for the informed and systematic development of more promising materials. Surface-enhanced Raman spectroscopy (SERS) is a potent tool for monitoring electrochemical evolution and dynamic doping in operational devices, offering enhanced sensitivity to subtle spectral changes. We demonstrate the utility of SERS for in situ tracking of doping in OMIECs in an organic light-emitting electrochemical cell (LEC) containing a conjugated polymer (poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]; MEH-PPV), a molecular anion (lithium triflate), and an electrolyte network (poly(ethylene oxide); PEO). SERS enhancement is achieved via an interleaved layer of gold particles formed by spontaneous breakup of a deposited thin gold film. The results successfully highlight the ability of SERS to unveil time-resolved MEH-PPV doping and polaron formation, elucidating the effects of triflate ion transfer in the operating device and validating the electrochemical doping model in LECs.

2.
BMC Nurs ; 23(1): 67, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38267940

ABSTRACT

BACKGROUND: Ensuring patient safety is of paramount importance in healthcare services. Sleep disorders not only have detrimental effects on the health of healthcare students but also significantly impair their performance, leading to an increased risk of medication errors. These errors can pose a grave threat to the safety and well-being of patients. It is crucial to address and mitigate sleep disorders among internship healthcare students to safeguard the quality of care and minimize potential patient harm. OBJECTIVES: This study aimed to investigate the predictors of Patient Safety Competency (PSC) based on the sleep quality of internship healthcare students. METHODS: A study was conducted on 331 students from the Ardabil School of Nursing and Midwifery at Ardabil University of Medical Sciences in northwest Iran from August to December 2022. The participants were selected by stratified random sampling. Data were collected using a demographic information form, the Pittsburgh Sleep Quality Index (PSQI), and the Health Professional Education in Patient Safety Survey (H-PEPSS). The collected data were analyzed using SPSS software version 22.0. Person correlation coefficients were used to examine the relationship between PSC level, its dimensions, and sleep quality, while multiple linear regression was conducted to identify the predictors of PSC. RESULTS: The competency of nurses in patient safety was average in both classroom and clinical settings. However, their ability to work as a team with other healthcare professionals scored the lowest. In addition, the quality of sleep was found to be a predictor of patient safety competency among healthcare students during their internships. CONCLUSIONS: It is important to note that healthcare students tend to have moderate patient safety competence (PSC), which is positively correlated with their sleep quality. Therefore, it is vital to identify the key factors that directly affect PSC. This would enable nursing and midwifery faculty administrators to take preventive measures to enhance patient safety competence in both classroom and clinical settings. Additionally, organizing educational workshops that engage students and improve their sleep quality could improve patient care. Practical courses are recommended for health professionals and students in clinical settings to enhance patient safety competencies. Additionally, student internships should receive hands-on training to improve teamwork and rest conditions.

3.
BMC Public Health ; 24(1): 18, 2024 01 02.
Article in English | MEDLINE | ID: mdl-38166862

ABSTRACT

BACKGROUND: Eating behavior is an essential aspect of life that can have long-term effects on health outcomes. Nutrition literacy is crucial for better health and well-being. It empowers individuals to make informed decisions about their nutrition and take control of their eating habits. OBJECTIVES: This study aimed to assess the relationship between nutritional literacy and eating behavior among nursing students at the nursing faculties of Ardabil University of medical sciences. METHODS: A cross-sectional correlational study was conducted in Ardabil province, northwest Iran. The study collected data through simple random sampling at nursing schools in Ardabil province, with 224 nursing students participating. The study collected data from a demographic information form, the nutritional literacy self-assessment questionnaire for students (NL-SF12), and the adult eating behavior questionnaire (AEBQ). The data were analyzed using SPSS version 14.0 software. RESULTS: Based on the results, nutritional literacy explains 44% of the variance in eating behavior and shows significant explanatory power in two sub-scales of eating behavior. The adjusted R2 values for food approach and food avoidance scales were 0.33 and 0.27, respectively. CONCLUSION: Given the significant relationship between nutritional literacy and eating behaviors among nursing students, nursing faculty managers and health policymakers should develop new public health strategies to increase nutritional literacy among nursing students.


Subject(s)
Health Literacy , Students, Nursing , Adult , Humans , Cross-Sectional Studies , Nutritional Status , Feeding Behavior , Surveys and Questionnaires , Health Literacy/methods
4.
Nurse Educ Pract ; 73: 103814, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37925833

ABSTRACT

BACKGROUND AND OBJECTIVE: Critical thinking is a crucial skill in nursing that nursing students should apply in their work environment. It involves analyzing, evaluating, and interpreting information. It is used in various topics such as disease diagnosis, treatment planning and implementation, monitoring, and evaluation of results, problem-solving, and decision-making in emergencies. This study in Iran aimed to evaluate factors associated with nursing students' critical thinking ability. STUDY METHOD: Following the STROBE guidelines, an analytical cross-sectional study was conducted in Ardabil province, northwest Iran. The study collected data through convenience sampling at nursing schools in Ardabil province, with a sample of 246 nursing students participating. The data collected from a demographic information form and the Persian version of the Nursing Critical Thinking in Clinical Practice Questionnaire were analyzed using SPSS version 22.0 software. RESULTS: The study found that the overall mean score of clinical critical thinking among nursing students was 313.87 ± 25.80 (range = 109-436). Based on this score, most students reported low (63%) or moderate (37%) clinical critical thinking levels. The highest and lowest mean scores between dimensions were related to the intellectual and cognitive (127.99 ± 13.30) and technical (17.25 ± 3.43), respectively. Multiple linear regression analysis revealed that semester and college were predictors of clinical critical thinking among nursing students. The selected predictors accounted for 19.3% of the total variance in clinical critical thinking scores (F = 9.396, p < 0.001). CONCLUSION: The study results showed that nursing students could have performed better in critical thinking ability. The study suggests that nursing education programs should prioritize teaching critical thinking skills in clinical settings as it is an essential subject in nursing education. With significant changes in nursing clinical environments, enhancing clinical critical thinking can improve nursing student performance clinically. Therefore, one of the crucial learning objectives in a clinical nursing course is to develop clinical critical thinking skills for nursing students.


Subject(s)
Education, Nursing, Baccalaureate , Students, Nursing , Humans , Iran , Cross-Sectional Studies , Learning , Thinking , Education, Nursing, Baccalaureate/methods
5.
Asian Pac J Cancer Prev ; 24(7): 2245-2252, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37505753

ABSTRACT

OBJECTIVE: This study was performed to assessment the health and carcinogenic risk of exposure to by-products of photocatalytic degradation of toluene in a spouted bed reactor Equipped with porous and non-porous draft tube. METHODS: For this purpose, titanium dioxide nanoparticles were used as photocatalysts and UV lamps as radiation sources. Degradation efficiency and CO2 selectivity were compared. By-products were also detected in three spouted bed reactors with and without a porous and non-porous draft tube. RESULT: The results revealed that the degradation efficiency of toluene in the spouted bed reactor without a draft tube was 30.75%. The insertion of porous and non-porous draft tubes in the spouted bed reactor increased the degradation efficiency up to 54.88% and 47.63%, respectively. Meantime, CO2 selectivity decreased from 100% to 50.8% within 180 min irradiation time in the spouted bed reactor without draft tube, while in the spouted bed reactors with porous and non-porous draft tube maintained at 89.85% and 84.35%, respectively. Toluene and four by-products with carcinogenic and non-carcinogenic risk of 0.002176 and 182.2, respectively, were detected in the spouted bed reactors without draft tube. However, no by-products with carcinogenic risk were found in the spouted bed reactor with porous and non-porous draft tube. CONCLUSION: photocatalytic degradation of toluene in a spouted bed reactor without a draft tube produces by-products with health and carcinogenic risks. The insertion of a porous and non-porous draft tube in spouted bed reactors provided mineralization more complete than spouted bed reactor without a draft tube by reducing the dead zone and providing appropriate contact between the toluene, photocatalyst, and UV. Therefore, prevent the formation of dangerous and carcinogenic by-products.


Subject(s)
Carcinogens , Toluene , Humans , Carbon Dioxide , Catalysis , Titanium
6.
Heliyon ; 9(6): e16428, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37303558

ABSTRACT

Determining the structural properties of aluminum metal foam is essential to predicting its acoustic behavior. Acoustic models are presented that show the relationship between the morphology of the absorber and the sound absorption coefficient (SAC). Optimizing the parameters affecting the SAC can be the maximum theoretically SAC achieved at each frequency. In the previous article (https://doi.org/10.32604/sv.2021.09729) the parameters of porosity percentage (Ω), pore size (D) and pore opening size (d) were optimized by the genetic algorithm and Lu model. In this study, the optimal aluminum metal foam was synthesized using Spark Plasma Sintering (SPS), with the maximum temperature of 420 °C and final pressure of 20 MPa in samples with thicknesses of 5, 10, 15 and 20 mm in different frequencies from 1000 to 6300 Hz. The crystal structure and microstructure of samples were investigated using XRD and SEM. Optimized metal foam SAC (0.67, 0.9, 1 and 1) and experimental peak SAC (0.44, 0.67, 0.76 and 0.82) were compared with the optimized SAC in 5, 10, 15 and 20 mm thicknesses, respectively. The values of the coefficient of determination (R2) according to multiple linear regression (MLR) for the two optimized SAC and experimental in thicknesses of 5, 10, 15 and 20 mm were 0.90, 0.95, 0.96 and 0.90, respectively. The results of this study show that porous metal foam can have a high absorption coefficient in any desired thickness and frequency by using the optimal morphology.

7.
Int J Prev Med ; 14: 125, 2023.
Article in English | MEDLINE | ID: mdl-38264555

ABSTRACT

Bachground: Noise is one of the most important harmful factors in the environment. There are limited studies on the effect of noise loudness on brain signals and attention. The main objective of this study was to investigate the relationship between exposure to different loudness levels with brain index, types of attention, and subjective evaluation. Methods: Four noises with different loudness levels were generated. Sixty-four male students participated in this study. Each subject performed the integrated visual and auditory continuous performance test (IVA-2) test before and during exposure to noise loudness signals while their electroencephalography was recorded. Finally, the alpha-to-gamma ratio (AGR), five types of attention, and the subjective evaluation results were examined. Results: During exposure to loudness levels, the AGR and types of attention decreased while the NASA-Tax Load Index (NASA-TLX) scores increased. The noise exposure at lower loudness levels (65 and 75 phon) leads to greater attention dysfunction than at higher loudness. The AGR was significantly changed during exposure to 65 and 75 phon and audio stimuli. This significant change was observed in exposure at all loudness levels except 85 phon and visual stimuli. The divided and sustained attention changed significantly during exposure to all loudness levels and visual stimuli. The AGR had a significant inverse correlation with the total score of NASA-TLX during noise exposure. Conclusions: These results can lead to the design of methods to control the psychological effects of noise at specific frequencies (250 and 4000 Hz) and can prevent non-auditory damage to human cognitive performance in industrial and urban environments.

8.
Int J Occup Saf Ergon ; 28(3): 1353-1361, 2022 Sep.
Article in English | MEDLINE | ID: mdl-33715596

ABSTRACT

Objectives. The present study aimed to investigate the effect of tonal noise and task difficulty on electroencephalography (EEG) and cognitive performance. Methods. Twelve healthy volunteers participated in the present study. Four noise signals were generated by four prominence tone levels (0, 2, 5 and 9) at background noise levels of 55 dBA and frequency of 500 Hz using the Test Tone Generator from Esser Audio (USA). The participants were asked to perform the tasks with low, moderate and high levels of difficulty while exposed to the noises in an acoustics laboratory. The values of reaction time, correct rate and missed numbers were recorded during each step. Moreover, the EEG signals were measured. Results. The results showed that higher tone level and more task difficulty significantly decreased the correct rate, and increased the miss numbers. However, no significant effect was observed on reaction times. Furthermore, tone level and task difficulty significantly increased activity of the θ and ß bands and decreased activity of the α band. Conclusion. Task difficulty and tone level could significantly affect the parameters of performance and the activity of EEG bands. Therefore, noise control can help sustain appropriate performance.


Subject(s)
Electroencephalography , Noise , Cognition , Electroencephalography/methods , Humans , Reaction Time
9.
Int J Occup Saf Ergon ; 28(4): 2509-2519, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34842059

ABSTRACT

In this study, a fuzzy Bayesian network (FBN) approach was proposed to analyze the domino effects of pool fire. Failure probabilities were calculated using triangular fuzzy numbers, the combined center of area (CoA)/sum-product method and the BN approach. Consequence modeling, probit equations and leaky-noisy-OR (L-NOR) gates were used to analyze the domino effects, and modify conditional probability tables (CPTs). Methanol storage tanks were selected to confirm the practical feasibility of the suggested method. The domino probability using bow-tie analysis (BTA) and FBN in the first and second levels was compared, and the ratio of variation was used for sensitivity analysis. Probability of the domino effect in the first and second levels (FBN) was 0.0071472631 and 0.0090630640, respectively. The results confirm this method is a suitable tool for analyzing the domino effects and that using FBN and L-NOR gate is a good way to assess the reliability of tanks.


Subject(s)
Fires , Methanol , Humans , Bayes Theorem , Reproducibility of Results , Probability , Fuzzy Logic
10.
Heliyon ; 8(12): e12520, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36593826

ABSTRACT

This study aims to assess the risk of chemicals warehouse using a Bayesian networks (BNs) and computational fluid dynamics (CFD). A methodology combining Bow-Tie (BT), fuzzy set theory (FST), and Bayesian network was employed, in which the BT was drawn for chemical spill scenarios. FST was utilized for the estimation of the basic events (BEs) occurrence probability, and the probability of interaction among a set of variables was obtained using BNs. Pool fire scenario radiation heat flux was evaluated using CFD code, fire dynamic simulator (FDS), and the solid flame model (SFM). Fail in forklift brake system (BE1), was the most significant cause for a chemical spill. Based on the CFD model, the heat flux is 31 kW/m2 at a distance of 3.5 m from the fire, decreasing to 6.5 m gradually. The maximum safety distance of 4 m is predicted by the CFD for heat flux that exceeds 12.5 kW/m2; however, SFM predicts approximately 4.5 m. According to the results, the amount of posterior risk is higher than the prior value. The framework presented in the chemicals warehouse for consequence analysis and dynamic risk assessment (DRA) of pool fire could be used for preventing the accidents and domino effects in the chemicals warehouse.

11.
Ind Health ; 59(6): 415-426, 2021 Nov 29.
Article in English | MEDLINE | ID: mdl-34588378

ABSTRACT

The aim of the present study was to first fabricate an electrospun PVC nanofiber web and then assess its applicability in sampling and measuring the concentration of airborne crystalline silica by comparing analysis results with a commercial PVC membrane filter under different ranges of airborne silica concentration. A filtration performance comparison was also made between an electrospun PVC web with nano-sized fibers and a commercial PVC membrane filter. Overall, the measured concentration of silica by the electrospun webs was 1.022 times higher than that of the commercial PVC filter in all studied ranges of silica concentration and the nanofiber media had higher filtration efficiency and lower pressure drop compared to the PVC membrane filter. This can be considered to be due to the lower fiber diameter and greater porosity (obtained from the 2D SEM image) of the electrospun nanofiber webs. This makes them suited for air pollutant sampling and determining its airborne concentration.


Subject(s)
Air Filters , Nanofibers , Feasibility Studies , Filtration , Humans , Silicon Dioxide
12.
J Therm Biol ; 97: 102872, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33863436

ABSTRACT

This study was conducted in order to investigate the effects of heat stress exposure on the concentrations of amino acids within the plasma and the brain of chicks. Methodology: Five electronic databases including; PubMed, Scopus, Web of Science, Embase and ProQuest were reviewed to find relative literature published until the March 8, 2019. A total of eight relative studies and 194 chicks were analyzed. The Random Effects model and the Fixed Effects model were performed. Using the Random Effects model for amino acids, a Standardized mean difference (SMD) of 2.05 and 1.46 was obtained for alanine and threonine concentrations respectively. This indicates a significant increase in the concentration of these amino acids within the plasma. An SMD of -2.68 and -2.46 was obtained for cysteine and proline concentrations respectively, this indicates a significant decrease in the concentration of these amino acids within the plasma. The pooled estimates regarding the effect of heat stress exposure on plasma amino acid concentrations for proline were -0.013. The SMDs obtained for amino acid concentrations within the brain (diencephalon) including leucine, methionine, valine and isoleucine were 1.799, 0.88, 2.11, 1.85, respectively, This indicates a significant increase in the concentration of these amino acids within the brain (P < 0.05). Comparing the SMD obtained for long-term heat exposure (two weeks) with the SMD obtained for short-term heat exposure shows that plasma amino acid concentrations including aspartic acid, glutamic acid, leucine, lysine, methionine, valine, isoleucine, tyrosine, glycine, proline, phenylalanine and threonine had all decreased. The relationship between heat exposure and changes in the concentration of some amino acids in the plasma is an important scientific finding.


Subject(s)
Amino Acids/metabolism , Brain/metabolism , Chickens/metabolism , Heat-Shock Response , Amino Acids/blood , Animals , Chickens/blood , Hot Temperature
13.
Article in English | MEDLINE | ID: mdl-33635459

ABSTRACT

Atmospheric parameters play a vital role in the dispersion of air pollutants. Benzene is a confirmed human carcinogen. It is also a neurotoxin and an irritant compound. The objective of this study was to examine the CFD simulation by Fluent16 software to simulate and analyze the effect of atmospheric conditions on the dispersion of benzene in eight different scenarios in a petroleum refinery. According to the results of this study, the highest and lowest impacts of atmospheric parameters occurred on spring days and autumn nights, respectively. Wind direction did not have a significant effect on the benzene distribution due to the artificial ceiling of piping installations in the computational domain. However, the wind speed had a critical role in the benzene dispersion. The maximum concentration occurred at 36- to 37-m distance from the inlet boundary for all scenarios except winter nights. On winter nights, this distance increased to 38 m. Benzene concentrations were the highest at their sources of release. They decreased after the artificial ceiling of the pipelines was at 5.5- to 7-m height where the air displacement was not sufficient, and therefore, leading to a gradual reduction in concentration. The accumulation of benzene concentration in the small domain was noticeable compared to the benzene concentration distributed in the total computational domain, and the authors recommended control measures in this domain. This study demonstrated CFD simulation methodology could enable the investigators to predict the benzene concentration dispersion in the atmosphere of a petroleum refinery plant. These findings can be used by occupational health engineers for health risk assessment of refinery personnel involved with maintenance operations and engineering control systems.

14.
Int J Occup Saf Ergon ; 27(3): 831-839, 2021 Sep.
Article in English | MEDLINE | ID: mdl-31438779

ABSTRACT

Purpose. Noise and heat are the most important physical hazardous agents that can affect physiological parameters. This study investigated the independent and combined effects of noise and heat exposure on human saliva cortisol and blood pressure. Methods. In this experimental study, 72 students were exposed to noise (at sound pressure levels of 45, 75, 85 and 95 dB(A)) and heat (at wet bulb globe temperatures [WBGTs] of 22, 29 and 34 °C) for 30 min. Samples of saliva and blood pressure were taken before and after each independent and combined exposure. Results. The results revealed that the average saliva cortisol and blood pressure in male and female subjects increased significantly after independent exposure to noise at 95 dB(A) and a WBGT of 34 °C. The combined exposure to noise and heat increased saliva cortisol and blood pressure, which was statistically significant for three combinations of 95 dB(A) at 34 °C, 95 dB(A) at 29 °C and 85 dB(A) at 34 °C. Conclusions. Combined exposure to noise and heat could affect saliva cortisol and blood pressure in both male and female groups. Further studies are recommended to capture other combinations of physical hazardous agents, especially in the field.


Subject(s)
Hot Temperature , Hydrocortisone , Blood Pressure , Female , Humans , Male , Noise , Saliva
15.
J Safety Res ; 72: 213-223, 2020 02.
Article in English | MEDLINE | ID: mdl-32199566

ABSTRACT

INTRODUCTION: The use of mobile phones while driving is known to be a distraction factor and a cause of accidents. The way in which different kinds of conversations affect the behavioral performance of the driver as well as the persistence of the effects are not yet fully understood. METHOD: In this study, in addition to comparing brain function and behavioral function in dual task conditions in three conversations types, the persistent effects of these types of conversations have also been traced. RESULTS: The results show that the content of the mobile phone conversation while driving is the cause of the persistent changes in behavioral and brain functions. Increased time headway and lane departure was observed during and up to 5 min after the emotional conversation was finished. EEG bands also varied in different types of conversations. Cognitive conversations caused an increase in the activity of the alpha and beta bands while emotional conversations enhanced the rate of gamma and beta bands. A meaningful correlation was found between changes in the theta and alpha bands and changes in behavioral performance both during the dual task condition and after the conversation was finished, was also observed. CONCLUSIONS: The content of the conversation is one of the most important factors that increase the risk of road accidents. This can also deteriorate the behavioral performance of the driver and can have persistent effects on behavioral performance and the brain. Practical applications: The findings of this study provide a basis to measure and tracing drivers' cognitive distractions induced by different levels of mental workload through physiological and behavioral performances.


Subject(s)
Automobile Driving , Cell Phone , Distracted Driving/statistics & numerical data , Attention/physiology , Automobile Driving/psychology , Iran
16.
Int J Biometeorol ; 64(5): 853-861, 2020 May.
Article in English | MEDLINE | ID: mdl-32036432

ABSTRACT

Occupational exposure to heat stress may lead to changes in blood cell count. The objective of this retrospective descriptive-analytical field study is to investigate the relationship between heat stress exposure and some immunological parameters among foundry workers. This study was carried out on 55 subjects of which, 35 were working in a foundry unit (exposed group) and 20 were working in a computer numerical control (CNC) machining unit (control group). The measurement method consisted of taking 10 cc of the subjects' blood between 10 am and 2 pm and then performing the automated blood cell counting and enzyme-linked immunosorbent assay (ELISA) on the sample. Environmental parameters such as noise levels, lighting, and the wet-bulb globe temperature (WBGT) index were measured at the subjects' workstations. All measurements were made in the first half of the month of July. The mean WBGT index was 22.5 ± 2.16 °C for the control group and 32.97 ± 3.22 °C for the exposed group. The laboratory test results show a significant decrease in white blood cell count and lymphocyte levels and a significant increase in neutrophil levels and neutrophil to lymphocyte ratio in exposed group compared with control ones (P < 0.05). IgM levels decrease under heat stress, but we do not observe significant differences between IgG and IgA levels between two groups. A significant negative correlation was observed between white blood cell count, lymphocyte levels, and IgM concentration with WBGT index and significant positive correlation was observed between neutrophil and neutrophil to lymphocyte ratio with WBGT index. No significant correlation was observed between sound pressure levels and light intensity with studied immunological parameters. In conclusion, under heat stress conditions, leukocytes levels and immunoglobulin concentration may reduce and it may weaken and suppress the human immune system.


Subject(s)
Heat Stress Disorders , Occupational Exposure , Heat-Shock Response , Hot Temperature , Humans , Retrospective Studies , Temperature
17.
AMB Express ; 10(1): 8, 2020 Jan 14.
Article in English | MEDLINE | ID: mdl-31938898

ABSTRACT

With increasing concerns about industrial gas contaminants and the growing demand for durable and sustainable technologies, attentions have been gradually shifted to biological air pollution controls. The ability of Pseudomonas putida PTCC 1694 (bacteria) and Pleurotus ostreatus IRAN 1781C (fungus) to treat contaminated gas stream with toluene and its biological degradation was compared under similar operating conditions. For this purpose, a biofilter on the laboratory scale was designed and constructed and the tests were carried out in two stages. The first stage, bacterial testing, lasted 20 days and the second stage, fungal testing, lasted 16 days. Inlet loading rates (IL) for bacterial and fungal biofilters were 21.62 ± 6.04 and 26.24 ± 7.35 g/m3 h respectively. In general, fungal biofilter showed a higher elimination capacity (EC) than bacterial biofilter (18.1 ± 6.98 vs 13.7 ± 4.7 g/m3 h). However, the pressure drop in the fungal biofilter was higher than the bacterial biofilter (1.26 ± 0.3 vs 1 ± 0.3 mm water), which was probably due to the growth of the mycelium. Fungal biofiltration showed a better performance in the removal of toluene from the air stream.

18.
Open Access Maced J Med Sci ; 7(17): 2924-2931, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31844459

ABSTRACT

BACKGROUND: It seems qualitative measurements of subjective reactions are not appropriate indicators to assess the effect of noise on cognitive performance. AIM: In this study, quantitative and combined indicators were applied to study the effect of noise on cognitive performance. MATERIAL AND METHODS: A total of 54 young subjects were included in this experimental study. The participants' mental workload and attention were evaluated under different levels of noise exposure including, background noise, 75, 85 and 95 dBA noise levels. The study subject's EEG signals were recorded for 10 minutes while they were performing the IVA test. The EEG signals were used to estimate the relative power of their brain frequency bands. RESULTS: Results revealed that mental workload and visual/auditory attention is significantly reduced when the participants are exposed to noise at 95 dBA level (P < 0.05). Results also showed that with the rise in noise levels, the relative power of the Alpha band increases while the relative power of the Beta band decreases as compared to background noise. The most prominent change in the relative power of the Alpha and Beta bands occurs in the occipital and frontal regions of the brain respectively. CONCLUSION: The application of new indicators, including brain signal analysis and power spectral density analysis, is strongly recommended in the assessment of cognitive performance during noise exposure. Further studies are suggested regarding the effects of other psychoacoustic parameters such as tonality, noise pitch (treble or bass) at extended exposure levels.

19.
EXCLI J ; 18: 501-512, 2019.
Article in English | MEDLINE | ID: mdl-31423130

ABSTRACT

As a dynamic system in which different factors affect human performance via dynamic interactions, mental workload needs a dynamic measure to monitor its factors and evidence in a complicated system, an approach that is lacking in the literature. The present study introduces a system dynamics-based model for designing feedback mechanisms related to the mental workload through literature review and content analysis of the previous studies. A human-based archetype of mental workload was detected from the data collection process. The archetype is presented at various stages, including dynamic theory, behavior over time, leverage points and model verification. The real validation of the dynamic model was confirmed in an urban train simulator. The dynamic model can be used to analyze the long-term behavior of the mental workload. Decision-makers can benefit from the developed archetypes in evaluating the dynamic impact of their decisions on accident prevention in the complicated systems.

20.
EXCLI J ; 18: 277-286, 2019.
Article in English | MEDLINE | ID: mdl-31338001

ABSTRACT

There are several scales for prediction of low back pain (LBP) occurrence, but most of them only consider occupational aspect. This study aimed to develop and validate a new biopsychosocial scale for the LBP prediction among nurses. In this mixed-method study, a scale was developed by integrating the findings from the literature review and the semi-structured interviews. The qualitative and quantitative face and content validation were then performed. The construct validation was performed based on the hypothesis testing by independent-samples t-test using the SPSS in a case study with 241 nurses. The reliability of the scale was also tested through 15-day interval test-retest reliability by Intra Class Correlation Coefficient (ICC). Then the Minimum Detectable Changes (MDC) and MDC % was calculated. The results showed that the three dimensions (occupational, psychosocial and individual), consisted of 40 items, predict LBP occurrence. Both the scale and the three sub-scales could differentiate known groups of nurses in terms of LBP. These groups were nurses: with/without LBP during the past 12 years, with a high/low occurrence of LBP, with/without co-morbidity, being female/male, with/without night shift, and with high/low repetition of loads/patients handling. The average measure ICC of the scale was 0.866 (P <0.001). The MDC95 (MDC %) was 14.86 (15.65 %). We concluded that the proposed scale is a simple and trustworthy tool which supports the multidimensional nature of LBP.

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