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Measurement of sound level in sports clubs with the approach of maintaining the health of athletes Texto completo
2021
Ling-Hsiang Chang | Hooman Bahmanpour | Ali Fahiminejad
The purpose of this study is to measure the sound level in bodybuilding clubs in Mashhad with the approach of maintaining the health of athletes. The metropolis of Mashhad, the capital of Khorasan Razavi province, is located in northeastern Iran. Fifteen bodybuilding clubs were randomly selected by networking method. The sound level in the clubs was measured in level A and as an equivalent level by the portable device and software Decibel X version 2019 and was compared with the sound standard (OSHA-90 dBA). Measurements were made in the morning and evening. The parameters of sound pressure level (SPL), mean sound level (LP) Ì continuous sound equivalent level (Leq) and individual daily dose of LAEp, d were calculated. The lowest sound pressure level in the morning was 76.5 decibels and the highest pressure level in the evening was 99.4 decibels. There was a direct relationship between sound pressure level and athletes' time in the club. The average sound level in sports clubs is equal to 87.6 dB and the level is equal to 90.61 and the daily individual dose of LEp, d athlete in the club is equal to 84.58 dB. The permissible duration of exposure to noise for athletes was estimated at 1 hour and 40 minutes. In the gymnasiums of Mashhad, athletes are exposed to high noise pollution and the possibility of physical and mental injuries is high.
Mostrar más [+] Menos [-]Investigating and identifying the effects of rural wastewater in Dena protected area and presenting an environmental management pattern Texto completo
2021
Mohammad Reza Sadegh Ali | Ali Zare | Mansour Pournouri
The purpose of this study was to identify the effects of discharge and discharge of wastewater from rural communities on biodiversity in the Dena Protected Area in the Central Zagros. This research is an applied grandson that has been done by library and field method. GIS tools and Landsat satellite have been used to extract and draw maps. In order to develop a comprehensive management plan and determine objectives and operational plans, the approach (SMART + P) and factor analysis method were used. For this purpose, the general principles of water resources management related to rural areas were extracted from global guidelines. In the next step, through library studies and questionnaires, the key stakeholders of water resources management in the study area were identified and the factor burden of each was determined, the highest factor weight belongs to the Ministry of Energy and rural water and sewage companies (16.50), followed by the General Department of Environmental Protection (15.30) and finally, local and rural communities have the lowest weight (10.43). Most of the rural wastewater in Dena protected area belongs to agricultural wastewater (53%), followed by domestic wastewater (28%) and finally, industrial wastewater (11%). The results of the good fit evaluation of the model show that GFI is equal to 0.977 and considering that it is more than 0.9, so it is acceptable in the region. Finally, the proposed model was designed to prepare a plan to assess the effects of rural wastewater on biodiversity in the region in 5 steps.
Mostrar más [+] Menos [-]Investigating the role and importance of sustainable architecture in optimal fuel consumption and pollution reduction (Case study: Semnan wind-Catchers) Texto completo
2021
Mahdi Yahyaei | Seyed Majid Mofidi Shemirani | Vahid Ahmadi
The purpose of this study is to investigate the role and importance of traditional Iranian architecture with emphasis on wind-catcher in reducing energy consumption in residential homes. Semnan province was selected as a study area and in the first step, suitable areas were identified for the establishment of wind-catcher in the province. In the second step, using two indices of Olgyay and effective temperature index (ET), the ted-cmperature of thermal comfort in the province was determined. Finally, the temperature difference was calculated by comparing the temperature in the residential houses adjacent to the wind-catcher and the internal temperature of the traditional buildings that had win-catchers. In the final step, the amount of energy consumption for heating or cooling in residential houses in Semnan province was estimated to determine the role and importance of wind-catchers. The results showed that April, May, June and October are in the zone of thermal comfort and there are times when wind-catchers will not be very useful in the province. On the other hand, July, August and September due to high temperatures and December, January, February and March due to high cold are good times to use wind-catchers. Also, the highest degree of conformity of the measured temperatures is observed in the cities of Semnan, Garmsar, Damghan and Shahrood, respectively. The amount of energy required to produce cooling is equal to 1700 kWh. However, if a wind-catcher is used, due to the reduction of coefficients and refrigeration losses, this amount will be equal to 1200 kWh.
Mostrar más [+] Menos [-]Competitive adsorption of pharmaceuticals in lake water and wastewater effluent by pristine and NaOH-activated biochars from spent coffee wastes: Contribution of hydrophobic and π-π interactions Texto completo
2021
Shin, Jaegwan | Kwak, Jinwoo | Lee, Yong-Gu | Kim, Sangwon | Choi, Minhee | Bae, Sungjun | Lee, Sang-Ho | Park, Yongeun | Chon, Kangmin
This study investigated the competitive adsorption mechanisms of pharmaceuticals (i.e., naproxen, diclofenac, and ibuprofen) toward the pristine and NaOH-activated biochars from spent coffee wastes (SCW) in lake water and wastewater effluent. The kinetic and isotherm studies revealed that the improved physicochemical characteristics and physically homogenized surfaces of the pristine SCW biochar through the chemical activation with NaOH were beneficial to the adsorption of pharmaceuticals (competitive equilibrium adsorption capacity (Qₑ, ₑₓₚ): NaOH-activated SCW biochar (61.25–192.07 μmol/g) > pristine SCW biochar (14.81–20.65 μmol/g)). The adsorptive removal of naproxen (Qₑ, ₑₓₚ = 14.81–18.81 μmol/g), diclofenac (Qₑ, ₑₓₚ = 15.73–20.00 μmol/g), and ibuprofen (Qₑ, ₑₓₚ = 16.20–20.65 μmol/g) for the pristine SCW biochar showed linear correlations with their hydrophobicity (log D at pH 7.0: ibuprofen (1.71) > diclofenac (1.37) > naproxen (0.25)). However, their Qₑ, ₑₓₚ values for the NaOH-activated SCW biochar (naproxen (176.39–192.07 μmol/g) > diclofenac (78.44–98.74 μmol/g) > ibuprofen (61.25–80.02 μmol/g)) were inversely correlated to the order of their log D values. These results suggest that the reinforced aromatic structure of the NaOH-activated SCW biochar facilitated the π-π interaction. The calculated thermodynamic parameters demonstrated that the competitive adsorption of pharmaceuticals on the NaOH-activated SCW biochar compared to pristine SCW biochar occurred more spontaneously over the entire pH (5.0–11.0) and ionic strength (NaCl: 0–0.125 M) ranges. These observations imply that the NaOH-activated SCW biochar might be potentially applicable for the removal of pharmaceuticals in lake water and wastewater effluent.
Mostrar más [+] Menos [-]The associations of nitrated polycyclic aromatic hydrocarbon exposures with plasma glucose and amino acids Texto completo
2021
He, Linchen | Hu, Xinyan | Day, Drew B. | Yan, Meilin | Teng, Yanbo | Liu, Xing (Lucy) | Yan, Erik | Xiang, Jianbang | Qiu, Xinghua | Mo, Jinhan | Zhang, Yinping | Zhang, Junfeng (Jim) | Gong, Jicheng
Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) have been widely studied for their mutagenic and carcinogenic effects. This study aims to investigate whether exposure to nitro-PAHs is associated with biomarkers of carbohydrate metabolism, an underlying risk factor for metabolic disorder. Early morning urine and blood samples were longitudinally collected two times with a four-week interval from 43 healthy adults. Five urinary amino-PAHs (1-aminonaphthalene, 2-aminonaphthalene, 9-aminophenanthrene, 2-aminofluorene, and 1-aminopyrene) were measured as biomarkers of nitro-PAH exposures. We measured plasma concentrations of glucose and six amino acids that can regulate insulin secretion, including aspartate (Asp), glutamate (Glu), glutamine (Gln), alanine (Ala), Arginine (Arg), and ornithine (Orn). We found that increasing concentrations of 9-aminophenanthrene were significantly associated with increasing glucose levels and with decreasing Asp, Glu, Ala, and Orn levels. We estimated that 26.4 %–43.8 % of the 9-aminophenanthrene-associated increase in glucose level was mediated by Asp, Glu, and Orn. These results suggest that exposure to certain nitro-PAHs affects glucose homeostasis, partly resulting from the depletion of insulin-stimulating amino acids (Asp, Glu, and Orn).
Mostrar más [+] Menos [-]Efficient anaerobic bioremediation of high-concentration benzo[a]pyrene in marine environments Texto completo
2021
Leng, Qingxue | Mu, Jun | Yang, Guangfeng
Benzo[a]pyrene (BaP), a persistent organic pollutant that may accumulate in sea sediments after oil spill or BaP chemical leakage accidents, considerably harms marine ecosystems and human health. Previous studies have been predominantly focused on its degradation at low concentrations, while the remediation of BaP pollution with high concentrations was neglected. Additionally, the metabolic pathways associated with its anaerobic degradation remain unclear. As a first attempt, super-efficient systems for BaP anaerobic degradation were established, and the corresponding metabolic pathways were elucidated in this study. The results showed that the BaP removal rate in BaP-only system with initial concentrations of 200 mg/L reached 3.09 mg/(L·d) within 45 days. Co-solvent, acetone promoted anaerobic BaP degradation (4.252 mg/(L·d)), while dichloromethane showed a newly-discovered co-metabolic effect. In the system with 500 mg/L of BaP and dichloromethane addition, the removal rate increased drastically (14.64 mg/(L·d)) at 400 mg/L turn point of BaP. Additionally, the corresponding microbial community-level metabolic network was firstly proposed.
Mostrar más [+] Menos [-]Emission factors, characteristics, and gas-particle partitioning of polycyclic aromatic hydrocarbons in PM2.5 emitted for the typical solid fuel combustions in rural Guanzhong Plain, China Texto completo
2021
Zhang, Bin | Sun, Jian | Jiang, Nan | Zeng, Yaling | Zhang, Yue | He, Kun | Xu, Hongmei | Liu, Suixin | Hang Ho, Steven Sai | Qu, Linli | Cao, Junji | Shen, Zhenxing
Solid fuel is a the most dominant energy source for household usages in developing countries. In this study, emission characteristics on organic carbon (OC), elemental carbon (EC) and fifty-two polycyclic aromatic hydrocarbons (PAHs) in gaseous and particulate phases from seven fuel-stove combinations were studied in a typical rural village in northwest China. For the PAHs, the highest gaseous and particulate phase emission factors (EFs) were both observed for bituminous coal with one-stage stoves, ranging from 459 ± 154 to 1.09 ± 0.36 × 10³ mg kg⁻¹. In contrast, the PAHs EFs for the clean briquette coal with two-stage stoves were two orders of magnitude lower than those of the bituminous coals. For parent PAHs (pPAHs) and total quantified PAHs (∑PAHs), they mainly contributed in gaseous phases with compositions of 69–79% and 64–70%, respectively. The gas-to-particle partitioning was mostly governed by the absorption. Moreover, the correlation coefficient (r) between EC and ∑PAHs, OC and parent PAHs (pPAHs), OC and nitro PAHs (nPAHs) were 0.81, 0.67 and 0.85, respectively, supporting that the PAHs species were potential precursors to the EC formation during the solid fuel combustion. The correlation analyses in this study further deduced that the formations of pPAHs and nPAHs were more closely related to that of OC than alkylated PAHs (aPAHs) and oxygenated PAHs (oPAHs). Diagnostic ratios of selective PAHs were calculated and evaluated as well. Among those, the ratio of retene (RET)/[RET + chyrene (CHR)] was found to be an efficient tool to distinguish coal combustion and biomass burning. In general, it was found that the amounts of pollutant emissions from clean briquette coal combustion were definitely lower than those from bituminous coal and biomass combustions. It is thus necessary to introduce and recommend the use of cleaner briquette coal as energy source.
Mostrar más [+] Menos [-]Estimating uncertainties of source contributions to PM2.5 using moving window evolving dispersion normalized PMF Texto completo
2021
Song, Lilai | Dai, Qili | Feng, Yinchang | Hopke, Philip K.
Conventional factor analyses can present problems in cases with changing numbers of sources and/or time-dependent source compositions. There is also lack of a reliable method to estimate uncertainties in the source contributions derived by positive matrix factorization (PMF). Applying a moving window evolving PMF to hourly PM₂.₅ composition dataset from a field campaign in Tianjin China that included the Spring and Lantern Festivals and the start of COVID-19 pandemic has substantially improved the apportionment compared to a conventional analysis using the entire data. Festival-related sources (e.g., fireworks and residential burning here) have been clearly identified and estimated during both the Spring and Lantern Festivals. During this period, the sources changed because the time period overlaps with the outbreak of COVID-19 and related reductions in activity during the lockdown that began on Lunar New Year. Multiple PMF runs providing source contribution estimates made it possible to estimate the uncertainties in these values. Our results show that winds-dependent sources like dust and distant point sources have larger uncertainties than the other sources. Compared with conventional PMF analyses, the current method may better reflect the actual emissions as well as being able to estimate uncertainties. Thus, this approach appears to be an improvement if the appropriate data are available.
Mostrar más [+] Menos [-]Metagenomic analysis of urban wastewater resistome and mobilome: A support for antimicrobial resistance surveillance in an endemic country Texto completo
2021
Rodríguez, Erika A. | Ramirez, Diego | Balcázar, José L. | Jiménez, J Natalia
In developing countries, where high levels of antimicrobial resistance are observed in hospitals, the surveillance of this phenomenon in wastewater treatment plants (WWTPs) and the environment is very limited, especially using cutting-edge culture-independent methods. In this study, the composition of bacterial communities, the resistome and mobilome (the pool of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), respectively) at a WWTP were determined using shotgun metagenomics and culture-based approaches. Wastewater samples were collected at four sampling points of a WWTP in Antioquia, Colombia. A total of 24 metagenomes were analyzed. Specifically, there were marked differences in bacterial community composition, resistome, and mobilome, according to the WWTP sampling points. Bacterial families of clinical importance such as Moraxellaceae, Aeromonadaceae, and Enterobacteriaceae were mainly detected in the WWTP influent and effluent samples. Genes encoding resistance to macrolide-lincosamide-streptogramin, β-lactams, and those conferring multidrug resistance (e.g., acrB, adeG, and mexD) were the most abundant. Moreover, some clinically important ARGs such as blaKPC₋₂ and blaCTX₋M, and others not reported locally, such as blaTEM₋₁₉₆, blaGES₋₂₃, blaOXA₋₁₀, mcr-3, and mcr-5 were frequently detected. Co-occurrence network analyses indicated a significant association of ARGs such as blaOXA₋₅₈ and blaKPC genes with Aeromonadaceae and Enterobacteriaceae. Among the markers of MGEs, intI1 and ISCR8 were the most frequently detected. Altogether, this work reveals the importance of shotgun metagenomics and culture-based approaches in antimicrobial resistance studies. The findings also support that WWTPs are hotspots for antimicrobial resistance, whose analysis constitutes a powerful tool to predict the impact of antimicrobial resistance in a population.
Mostrar más [+] Menos [-]Prokaryotic community succession and assembly on different types of microplastics in a mariculture cage Texto completo
2021
Hou, Dandi | Hong, Man | Wang, Kai | Yan, Huizhen | Wang, Yanting | Dong, Pengsheng | Li, Daoji | Liu, Kai | Zhou, Zhiqiang | Zhang, Demin
Microplastics have emerged as a new anthropogenic substrate that can readily be colonized by microorganisms. Nevertheless, microbial community succession and assembly among different microplastics in nearshore mariculture cages remains poorly understood. Using an in situ incubation experiment, 16S rRNA gene amplicon sequencing, and the neutral model, we investigated the prokaryotic communities attached to polyethylene terephthalate (PET), polyethylene (PE), and polypropylene (PP) in a mariculture cage in Xiangshan Harbor, China. The α-diversities and compositions of microplastic-attached prokaryotic communities were significantly distinct from free-living and small particle-attached communities in the surrounding water but relatively similar to the large particle-attached communities. Although a distinct prokaryotic community was developed on each type of microplastic, the communities on PE and PP more closely resembled each other. Furthermore, the prokaryotic community dissimilarity among all media (microplastics and water fractions) tended to decrease over time. Hydrocarbon-degrading bacteria Alcanivorax preferentially colonized PE, and the genus Vibrio with opportunistically pathogenic members has the potential to colonize PET. Additionally, neutral processes dominated the prokaryotic community assembly on PE and PP, while selection was more responsible for the prokaryotic assembly on PET. The assembly of Planctomycetaceae and Thaumarchaeota Marine Group I taxa on three microplastics were mainly governed by selection and neutral processes, respectively. Our study provides further understanding of microplastic-associated microbial ecology in mariculture environments.
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