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Background and Objective: Diesel storage tanks play a crucial role in hospitals and are constantly at risk of chemical release, explosion, and fire. The present study aimed to assess the consequences of a diesel tank leak in one of Iran’s specialized hospitals. Materials and Methods: This study utilized an applied research approach with scenario modeling using PHAST software (version 8.4). A discharge rate of 1000 L/min was employed for the fixed-duration release scenario. The necessary information for the software, including tank and meteorological data, was collected. The mortality rate and danger radius were calculated and analyzed for two tank volumes of 23600 and 12000 m3 in conditions of Sabzevar region in winter and 1.5 F of the software. Results: According to the tank type and substance released into the environment, the software displayed a pool fire. The most hazardous scenario was determined to be leakage from the 23600 m3 tank in weather conditions of Sabzevar (26°C, wind speed 15 m/s in winter). The maximum and minimum radiation heat from the fire were calculated at 44.7 and 94.2 meters, respectively. The mortality rates for exposure levels of 37.5 kw/m2, 12.5 kw/m2, and 4 kw/m2 were found to be 98.7%, 6.5%, and approximately zero, respectively. Conclusion: Fire safety in hospitals is a critical issue that requires a thorough examination of the factors that can lead to ignition and explosion. To mitigate these risks, it is recommended to strategically place diesel tanks, develop safety models for roadways, construct dams and dikes near tanks, regularly inspect equipment for corrosion and deterioration, and install sensors to detect leaks. These measures are essential for ensuring the safety of patients, staff, and hospital facilities.

Introduction: In recent years, exposure to nanomaterials has been known as a challenge among occupational health experts. In this line, personal protective equipment has been considered as a solution to reduce the worker’s exposure. Since respiratory and skin tracts represent the most common workplace exposure routes, knowledge of the efficiency of respiratory and skin protection equipment is particularly important. So, the aim of this study is the assessment of the efficiency of respiratory and skin protection equipment toward controlling nanoparticles in the workplace with a scoping review approach. Material and Methods: This study was conducted in 2022 with a scoping review approach. Arksey and O’Malley’s five-step framework was chosen as the research method. The search strategy was followed in the databases necessary to access the research data, including PubMed, Google Scholar, Science Direct, Web of Science, and Scopus. Also, EndNote X9® and Microsoft Excel software were used to collect and analyze studies, respectively. Results: In the first step, 1014 articles were identified. Finally, 38 articles were included in the study to examine quantitative and qualitative information about the efficiency of respiratory and skin protective equipment. Twenty-five articles were related to breathing masks, and six studies were about protective gloves, and seven other articles were devoted to protective clothing. According to the studies of breathing masks, the mean total penetration of nanoparticles was estimated at 2.27%. Also, based on the studies of protective clothing, the maximum penetration of nanoparticles was 30nm for protective clothing made of polypropylene and polyethylene with different layers. Conclusion: Although the efficiency of existing personal protective equipment showed a good result for controlling nanoparticles, the size of nanoparticles is one of the essential parameters in determining the efficiency of the equipment, which should be considered the workplaces. So, it is recommended that more studies be considered to improve their efficiency, and standard tests should be developed to evaluate them.

Introduction: The aim of this study was to investigate the effect of particle size (mesh) on the sound absorption coefficient of the absorbers made from Arundo Donax reed and to determine the optimal mesh for sound absorption. Material and Methods: After crushing the reed stems in 10, 30, 20, 16, and 40 mesh sizes, they were washed with 5% NaOH. To make the samples 3 and 10 cm in diameter, 10% PVA was used as a binder, and the impedance of the two-channel tube was used according to ISO 10534-2 standard to determine the absorption coefficient. 22 samples of meshes 16 and 20 were made to achieve the optimal mesh based on the optimized RSM method, and the SAA index was used to compare the samples and determine the optimal mesh. Results: The highest absorption peak was related to meshes 16 and 20 at the frequency of 2500 Hz, which is 0.94 and 0.98 ,respectively. The effect of increasing the thickness and density on the absorption coefficient is evident. The results have shown the effect of increasing the thickness and density on the absorption coefficient in mesh 20 in such a way that by increasing the density from 150 to 250 and the thickness from 10 to 30 mm, the absorption coefficient has increased from 35 to 63.5%. The optimal sample was mesh 20 with a thickness of 30 and a density of 250 kg/m3, which had the highest average absorption (SAA=0.57). The greater distance between the real and imaginary parts of the impedance shows the reactivity of the sample. In mesh 16 this distance is greater, as a result, mesh 16 has more reactivity and correspondingly less absorption. Conclusion: The role of particle mesh as one of the important and influencing parameters on absorption coefficient has been investigated in this study.

Introduction: The acoustic performance of natural fiber adsorbents has been investigated in numerous studies. A part of these materials show a poor adsorption within the frequency range of less than 1000 Hz. In the present study, attempts were made to investigate the effect of layout sequence of double-layered composites consisting of natural and synthetic fibers on improving the acoustic adsorption coefficient of natural fiber in the low-frequency range (63 to 1000 Hz) using the numerical finite element method. Material and Methods: In this study, the finite element method and the Johnson-Champoux-Allard model in COMSOL software version 5.3a were used to investigate the acoustic performance of the double-layered composites consisting of natural and synthetic adsorbents. The acoustic absorbers under study included date palm fiber, polyurethane foam and cellular rubber. Each double-layered composite included a date palm fiber with 10mm in thickness and a synthetic adsorbent (polyurethane foam or cellular rubber) with 10mm in thickness. In sum, four double-layered composite structures with different layouts of adsorbents in each structure were studied. Results: The location of natural fiber can play a critical role in the acoustic performance of the double-layered composite structures such that comparing the studied double-layered composites revealed that when the natural fiber was the first layer exposed to the normal sound in the double-layered composites with 20mm in thickness, the trend of acoustic performance was approximately the same as the single-layered composite of natural fiber with 20mm in thickness; but in the composite structures, when the synthetic adsorbent was the first layer exposed to the sound, the trend of acoustic absorption was improved. Conclusion: On the basis of the results, the double-layered composite structure with a higher-density and lower-porosity upper layer showed a better acoustic absorption trend than the single-layered composite including the natural adsorbent.

Abstract Introduction: The Wet Bulb Globe Temperature (WBGT) is still widely applied as a preliminary tool for evaluating the heat stress. This index faces some limitations not considered yet. This systematic review was conducted aiming at highlighting some limitations for development of the WBGT index. Method: The present study was organized using more extensive databases: PubMed, Google Scholar, Scientific Information Databases (SID), Elsevier, Web of Science, Scopus, Irandoc, Magiran, and Iran Medex. The used search terms were WBGT index, Heat stress, Thermal Stress, Heat strain, Wet Bulb Globe Temperature, Hot Condition, Occupational Health and Occupational Exposure indices. In this study, 69 articles from 1950 to December 2020 were assessed. Conclusion: The WBGT index, despite having some advantages, suffers limitations which should be considered for a more accurate estimate of thermal stress. This study pointed to the new limitations; including, the value of WBGT is not clear for persons whose working in a seated posture. In addition, this index is used for adapted people who have used enough water and salt while water and salt are not always available to workers in all hot working environments, hence using this index will come with an error. Also, in heterogeneous environments, if the heat source is at the height of the face and legs, no coefficient would be taken into account for these areas.

Background: Porous absorbers are highly effective at attenuating high-frequency noise, yet they face inherent limitations, including reduced absorption at lower frequencies and vulnerability to environmental factors. Combining porous materials with Micro Perforated Panels (MPP) offers a solution but often sacrifices bandwidth. This study deals with optimizing parameters to extend the bandwidth toward higher frequencies, considering health concerns related to high-frequency noise exposure. Materials & Methods: This study used Finite Element Numerical Simulation (FEM) in COMSOL to model a porous material and MPP composite. It examined parameters like material thickness, air gap, hole diameter, panel thickness, MPP perforation percentage, and layer configurations. The goal was to find the best configuration to expand bandwidth, selecting and fixing the most effective parameter at each stage. Results: Findings from the simulated model aligned with direct impedance tube measurements. Enlargement of the fibrous material thickness, up to practical limits, expanded bandwidth. Optimizing MPP parameters involved minimizing hole diameter and panel thickness while maximizing perforations. The most effective layer configuration for bandwidth expansion consisted of an air layer, porous material, another air layer, additional porous material, and the MPP layer. Conclusions: Careful parameter selection can significantly increase bandwidth and absorption coefficients at higher frequencies. The incorporation of MPP enhances the composite's overall resilience, offering mechanical strength, resistance to environmental factors, and aesthetic appeal. The high precision of FEM simulations positions them as a valuable alternative to direct measurements such as impedance tube assessments. This study provides a comprehensive approach to improving porous absorber performance. [ABSTRACT FROM AUTHOR]

Background and Objective: Diesel storage tanks play a crucial role in hospitals and are constantly at risk of chem ical release, explosion, and fire. The present study aimed to assess the consequences of a diesel tank leak in one of I ran's specialized hospitals. Materials and Methods: This study utilized an applied research approach with scenario modeling using PHAST software (version 8.4). A discharge rate of 1000 L/min was employed for the fixed-duration release scenario. The necessary information for the software, including tank and meteorological data, was collected. The mortality rate and danger radius were calculated and analyzed for two tank volumes of 23600 and 12000 m3 in conditions of Sabzevar region in winter and 1.5 F of the software. Results: According to the tank type and substance released into the environment, the software displayed a pool fire. The most hazardous scenario was determined to be leakage from the 23600 m3 tank in weather conditions of Sabzevar (26°C, wind speed 15 m/s in winter). The maximum and minimum radiation heat from the fire were calculated at 44.7 and 94.2 meters, respectively. The mortality rates for exposure levels of 37.5 kw/m2, 12.5 kw/m2, and 4 kw/m2 were found to be 98.7%, 6.5%, and approximately zero, respectively. Conclusion: Fire safety in hospitals is a critical issue that requires a thorough examination of the factors that can lead to ignition and explosion. To mitigate these risks, it is recommended to strategically place diesel tanks, develop safety models for roadways, construct dams and dikes near tanks, regularly inspect equipment for corrosion and deterioration, and install sensors to detect leaks. These measures are essential for ensuring the safety of patients, staff, and hospital facilities. [ABSTRACT FROM AUTHOR]

Objectives Acute appendicitis is the most common surgical condition in children. In the UK, appendicectomy is the most common treatment with non-operative management unusual. Due to concerns about the risk of SARS-CoV-2 transmission during surgical procedures, surgeons were advised to consider non-operative treatment and avoid laparoscopy where possible. This study aims to report management and outcomes, to date, of children with appendicitis in the UK and Ireland during the COVID-19 pandemic.Design Survey of consultant surgeons who treat children with appendicitis that informed a prospective multicentre observational cohort study.Setting Data were collected from centres in the UK and Ireland for cases admitted between 1 April and 31 May 2020 (first 2 months of the COVID-19 pandemic) at both general surgical and specialist paediatric surgical centres.Participants The study cohort includes 838 children with a clinical and/or radiological diagnosis of acute appendicitis of which 527 (63%) were male.Main outcomes measured Primary outcome was treatment strategy used for acute appendicitis. Other outcomes reported include change in treatment strategy over time, use of diagnostic imaging and important patient outcomes to 30 days following hospital admission.Results From very early in the pandemic surgeons experienced a change in their management of children with appendicitis and almost all surgeons who responded to the survey anticipated further changes during the pandemic. Overall, 326/838 (39%) were initially treated non-operatively of whom 81/326 (25%) proceeded to appendicectomy within the initial hospital admission. Of cases treated initially surgically 243/512 (48%) were performed laparoscopically. Diagnostic imaging was used in 445/838 (53%) children. Cases treated non-operatively had a shorter hospital stay than those treated surgically but hospital readmissions within 30 days were similar between groups. In cases treated surgically the negative appendicectomy rate was 4.5%. There was a trend towards increased use of surgical treatment and from open to laparoscopic appendicectomy as the pandemic progressed.Conclusion Non-operative treatment of appendicitis has been widely used for the first time in children in the UK and Ireland and is safe and effective in selected patients. Overall patient outcomes do not appear to have been adversely impacted by change in management during the pandemic thus far.

Evaluation studies of outcomes used in clinical research and their consistency are appearing more frequently in the literature, as a key part of the core outcome set (COS) development. Current guidance suggests such evaluation studies should use systematic review methodology as their default. We aimed to examine the methods used. We searched the Core Outcome Measures in Effectiveness Trials (COMET) database (up to May 2019) supplementing it with additional resources. We included evaluation studies of outcome consistency in clinical studies across health subjects and used a subset of A MeaSurement Tool to Assess systematic Reviews (AMSTAR) 2 (items 1-9) to assess their methods. Of 93 included evaluation studies of outcome consistency (90 full reports, three summaries), 91% (85/93) reported performing literature searches in at least one bibliographic database, and 79% (73/93) was labelled as a "systematic review". The evaluations varied in terms of satisfying AMSTAR 2 criteria, such that 81/93 (87%) had implemented PICO in the research question, whereas only 5/93 (6%) had included the exclusions list. None of the evaluation studies explained how inconsistency of outcomes was detected, however, 80/90 (88%) concluded inconsistency in individual outcomes (66%, 55/90) or outcome domains (20%, 18/90). Methods used in evaluation studies of outcome consistency in clinical studies differed considerably. Despite frequent being labelled as a "systematic review", adoption of systematic review methodology is selective. While the impact on COS development is unknown, authors of these studies should refrain from labelling them as "systematic review" and focus on ensuring that the methods used to generate the different outcomes and outcome domains are reported transparently.

Background: Recent years have seen many attempts to increase the efficiency and reduce the pressure drop of High-Efficiency Particulate Air Filter (HEPA) filters in removing microorganisms through shape change and the use of photocatalysts. This study is the first scoping review of the effects of photocatalysts on increasing the efficiency of HEPA filters in the elimination of airborne microorganisms. Materials and Methods: PubMed, Scopus, Irandoc, and Magiran databases were searched for relevant articles. Based on select keywords and the study objectives and applying the inclusion and exclusion criteria, eight from a total of 315 articles were identified, two of which were typical in the review of efficiency and pressure drop. These articles investigated the effect of photocatalyst and filter shape on the efficiency and pressure drop of HEPA filters. Results: These studies were released from 2000 to 2021. TiO2, with its long-term interactions with microorganisms, the attack of superoxide radicals (O2-), and the release of K+, RNA, proteins, and other essential components will cause their destruction. Ultraviolet rays at a wavelength of 254 nm remove bacteria on the surface of the filter. The synergy of the inherent ability of UV radiation with TiO2 through nucleic acid and protein damage in microorganisms and the generation of oxidative radicals increases the efficiency of HEPA filters compared to either one alone. Conclusion: The photocatalysts with ultra-violet rays on the HEPA filter can reduce the problem of microorganism growth and increase indoor air quality. [ABSTRACT FROM AUTHOR]

Introduction: The Wet Bulb Globe Temperature (WBGT) is still widely applied as a preliminary tool for evaluating heat stress. This index faces some limitations not considered yet. This systematic review was conducted aiming at highlighting some limitations for the development of the WBGT index. Method: The present study was organized using more extensive databases: PubMed, Google Scholar, Scientific Information Databases (SID), Elsevier, Web of Science, Scopus, Irandoc, Magiran, and Iran Medex. The used search terms were WBGT index, Heat stress, Thermal Stress, Heat strain, Wet Bulb Globe Temperature, Hot Condition, Occupational Health, and Occupational Exposure indices. In this study, 69 articles from 1950 to December 2021 were assessed. Conclusion: The WBGT index, despite having some advantages, suffers limitations that should be considered for a more accurate estimate of thermal stress. This study pointed to the new limitations; including, the value of WBGT is not clear for persons whose working in a seated posture. The additional problem with the use of this index is that it is used for adapted people who have consumed enough water and salt, while in most hot working environments neither water nor salt is always readily available. Therefore, using this index will cause an error. Also, in heterogeneous environments, if the heat source is near the head or legs, a coefficient will not be applied to these regions. The results of the study demonstrate that, because of the limitations of the WBGT index, it is recommended that this index be used along with other indicators and physiological parameters to assess heat stress until more extensive studies are conducted in an attempt to improve and remove its limitations. [ABSTRACT FROM AUTHOR]

Nowadays, great research efforts are devoted to investigate energy efficiency practices in buildings as a response to the rapid consumption of the depleting fuels and the associated environmental challenges. This paper presents a systematic approach that was implemented in the Islamic University of Gaza (IUG), Palestine to develop and evaluate a training program on energy efficiency in buildings. The aim of the training program was to bring together engineers and architects from a variety of governmental, non-governmental, and international organizations to learn and discuss energy efficiency practices in buildings considering the local conditions of the Gaza Strip. This study reports the methods used to design, implement, and assess the program including a questionnaire, focus group, and reflection workshop. The study concluded that there is a great need in the Gaza Strip for such training courses. There is also a need to expand the scope of the training to cover further categories of people involved in the construction sector, and to use additional training formats such as on-job, and over-distance training. [ABSTRACT FROM AUTHOR]

Abdominal actinomycosis is a rare disease caused by the Actinomyces bacteria. We report a case series of two similar cases with a mismatch between the initial differential diagnosis, the radiological findings, the surgical findings, and the actual histological result. The first case is a 25-year-old woman with a month's history of right-sided abdominal pain. The diagnostic workup including computed tomography (CT) showed possible acute appendicitis, in addition to ascending colon looking abnormal with inflammatory changes and adjacent peritoneal nodules. A diagnostic laparoscopy revealed a normal-looking appendix and a hard mass involving the ascending colon potentially of inflammatory or malignant origin. A laparoscopic right hemicolectomy was performed. Surprisingly, the histology concluded actinomycosis. The second case is a 38-year-old woman with a six-week history of lower abdominal pain and right iliac fossa (RIF) swelling. The diagnostic workup including a CT scan showed a complex mass suggesting complicated appendicitis, pelvic inflammatory disease, or neoplastic process. Furthermore, magnetic resonance imaging (MRI) of the pelvis showed complex bilateral cystic lesions in both iliac fossas with an abscess formation within the subcutaneous fat overlying the lower pelvis. The patient underwent an ultrasound (US)-guided drainage of the subcutaneous pelvic collection and a diagnostic laparoscopy that showed an inflamed mass with dense adhesions to the anterior abdominal wall. Intraoperative biopsies were taken to confirm the diagnosis, which ultimately confirmed severe pelvic actinomycosis. Both patients were discharged home and received extended antibiotic treatment according to microbiology guidelines with good outcomes. Both cases are interesting because there was a mismatch between the initial differential diagnosis, the radiological findings, the intraoperative findings, and the final histology. Reported cases in the literature highlight the diagnostic challenges of abdominal actinomycosis, as it often presents with atypical symptoms and imaging findings sometimes mimic malignancy leading to surgical intervention., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Ayoub et al.)