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1.
Plants (Basel) ; 13(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38475467

RESUMO

The effects of simulated acid rain (SAR) on the photosynthetic performance of subtropical coniferous species have not been thoroughly investigated. In this study, we treated two coniferous species, Pinus massoniana (PM) and Cunninghamia lanceolata (CL), with four gradients of SAR and then analyzed their photosynthetic activities through measurements of gas exchange, prompt fluorescence (PF), delayed fluorescence (DF), and modulated reflection at 820 nm (MR820). Gas exchange analysis indicated that the decrease in the net photosynthetic rate (Pn) in PM and CL was unrelated to stomatal factors. For the PF transients, SAR induced positive K-band and L-band, a significant reduction in photosynthetic performance index (PIABS), the quantum yield of electron transfer per unit cross-section (ETO/CSm), and maximal photochemical efficiency of photosystem II (Fv/Fm). Analysis of the MR820 kinetics showed that the re-reduction kinetics of PSI reaction center (P700+) and plastocyanin (PC+) became slower and occurred at later times under SAR treatment. For the DF signals, a decrease in the amplitude of the DF induction curve reduced the maximum value of DF (I1). These results suggested that SAR obstructed photosystem II (PSII) donor-side and acceptor-side electron transfer capacity, impaired the connectivity between PSII and PSI, and destroyed the oxygen-evolving complex (OEC). However, PM was better able to withstand SAR stress than CL, likely because of the activation of a protective mechanism.

2.
Mol Nutr Food Res ; 68(5): e2300784, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38314939

RESUMO

SCOPE: Premature ovarian insufficiency (POI) is a common female infertility problem, with its pathogenesis remains unknown. The NOD-like receptor family pyrin domain-containing 3 (NLRP3)-mediated pyroptosis has been proposed as a possible mechanism in POI. This study investigates the therapeutic effect of α-ketoglutarate (AKG) on ovarian reserve function in POI rats and further explores the potential molecular mechanisms. METHODS AND RESULTS: POI rats are caused by administration of cyclophosphamide (CTX) to determine whether AKG has a protective effect. AKG treatment increases the ovarian index, maintains both serum hormone levels and follicle number, and improves the ovarian reserve function in POI rats, as evidence by increased the level of lactate and the expression of rate-limiting enzymes of glycolysis in the ovaries, additionally reduced the expression of NLRP3, Gasdermin D (GSDMD), Caspase-1, Interleukin-18 (IL-18), and Interleukin-1 beta (IL-1ß). In vitro, KGN cells are treated with LPS and nigericin to mimic pyroptosis, then treated with AKG and MCC950. AKG inhibits inflammatory and pyroptosis factors such as NLRP3, restores the glycolysis process in vitro, meanwhile inhibition of NLRP3 has the same effect. CONCLUSION: AKG ameliorates CTX-induced POI by inhibiting NLRP3-mediated pyroptosis, which provides a new therapeutic strategy and drug target for clinical POI patients.


Assuntos
Reserva Ovariana , Insuficiência Ovariana Primária , Humanos , Ratos , Feminino , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ácidos Cetoglutáricos/farmacologia , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/tratamento farmacológico , Piroptose , Células da Granulosa/metabolismo , Inflamassomos/metabolismo
3.
Int J Occup Saf Ergon ; 30(1): 56-63, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36516459

RESUMO

Objectives. This study aimed to identify the prevalence of multi-site work-related musculoskeletal disorders (WMSDs) in Chinese footwear industry workers from 2018 to 2020 and explore the possible influencing factors of WMSDs. Methods. 7106 subjects from 26 large shoe factories in China were investigated using the epidemiological cross-sectional survey method by using the Nordic musculoskeletal questionnaire (NMQ). Results. The total prevalence of WMSDs in the study subjects was 36.8% (2616/7106). Among them, the prevalence of multi-site WMSDs was 26.1% (1858/7106). The proportion of multi-site WMSDs involving two sites was the largest (31.38%). In addition, the results showed that the risk factors of multi-site WMSDs were gender, marital status, long current job experience, poor health, poor working posture, etc. Conclusions. The prevalence of WMSDs was high in the Chinese footwear industry. Based on the results, therefore, it seems necessary to improve work posture, work organization and workenvironment to prevent WMSDs.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Fatores de Risco , Inquéritos e Questionários , China/epidemiologia , Prevalência
4.
Dalton Trans ; 52(38): 13507-13516, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37712245

RESUMO

In order to balance the contradiction between mesopore introduction and loss of microporosity, a surface modification strategy is proposed by selectively adsorbing organic alkaline molecules on Beta molecular sieves before NaOH etching. Organic alkaline molecules adsorb on framework aluminum sites and the protective function of organic bases is affected by the adsorption configuration and physical barrier effect of organic bases. Organic alkaline molecules serve as a protective agent to increase the bond length of Al-O bonds. Therefore, the as-synthesized hierarchical Beta molecular sieves have more acid sites due to the preservation of aluminum atoms. When employed as catalysts in the dehydration reaction of glucose, 5-hydroxymethylfurfural (5-HMF) is obtained under the synergistic effect of Brønsted and Lewis acid sites. The unique contribution is to realize the porosity regulation and alleviate the acidity loss of Beta molecular sieves. These results are important to broaden the application fields of aluminum-silicon molecular sieves especially for large molecule-engaged acid catalyzed reactions.

5.
J Colloid Interface Sci ; 649: 1-9, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37331105

RESUMO

Exploring high-efficiency electrocatalysts to boost the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is pivotal to the large-scale applications for clean and renewable energy technologies, such as fuel cells, water splitting, and metal-air batteries. Herein, by means of density functional theory (DFT) computations, we proposed a strategy to modulate the catalytic activity of transition metal-nitrogen-carbon catalysts through their interface engineering with graphdiyne (TMNC/GDY). Our results revealed that these hybrid structures exhibit good stability and excellent electrical conductivity. Especially, CoNC/GDY was identified as a promising bifunctional catalyst for ORR/OER with rather low overpotentials in acidic conditions according to the constant-potential energy analysis. Moreover, the volcano plots were established to describe the activity trend of the ORR/OER on TMNC/GDY using the adsorption strength of the oxygenated intermediates. Remarkably, the d-band center and charge transfer of the TM active sites can be utilized to correlate the ORR/OER catalytic activity and their electronic properties. Our findings not only suggested an ideal bifunctional oxygen electrocatalyst, but also provided a useful strategy to obtain highly efficient catalysts by interface engineering of two-dimensional heterostructures.

6.
Nanoscale ; 15(27): 11616-11624, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37377102

RESUMO

Searching for bifunctional oxygen electrocatalysts with good catalytic performance to promote the oxygen evolution/reduction reactions (OER/ORR) is of great significance to the development of sustainable and renewable clean energy. Herein, we performed density functional theory (DFT) and machine-learning (DFT-ML) hybrid computations to investigate the potential of a series of single transition metal atoms anchored on the experimentally available MnPS3 monolayer (TM/MnPS3) as the bifunctional electrocatalysts for the ORR/OER. The results revealed that the interactions of these metal atoms with MnPS3 are rather strong, thus guaranteeing their high stability for practical applications. Remarkably, the highly efficient ORR/OER can be achieved on Rh/MnPS3 and Ni/MnPS3 with lower overpotentials than those of metal benchmarks, which can be further rationalized by establishing the volcano and contour plots. Furthermore, the ML results showed that the bond length of TM atoms with the adsorbed O species (dTM-O), the number of d electrons (Ne), the d-center (εd), the radius (rTM) and the first ionization energy (Im) of the TM atoms are the primary descriptors featuring the adsorption behavior. Our findings not only suggest novel highly efficient bifunctional oxygen electrocatalysts, but also provide cost-effective opportunities for the design of single-atom catalysts using the DFT-ML hybrid method.

7.
Work ; 76(3): 1219-1231, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37248938

RESUMO

BACKGROUND: The automotive industry is labor-intensive, and workers are involved in highly repetitive tasks, long hours, and medium to low workloads, resulting in work-related musculoskeletal disorders (WMSDs), which have become a major health concern for workers in this industry. China is a major automotive country with tens of thousands of auto repair workers, but their conditions of WMSDs have been poorly reported. OBJECTIVE: This work aimed to analyze the current prevalence of WMSDs and their associated risk factors among automobile maintenance workers. METHODS: A total of 539 respondents from 50 automotive repair and maintenance companies in China were selected to investigate the prevalence of WMSDs via the modified Nordic Musculoskeletal Disorders Questionnaire. Chi-square test and logistic regression models were applied to analyze their associated risk factors. RESULTS: The total prevalence of WMSDs among 539 workers was 32.8%. The top three body parts for prevalence were the lower back (17.1%), neck (16.3%), and shoulders (14.5%). The highest prevalence of WMSDs was found in the neck (23.6%) and lower back (14.3%) for sheet metal workers and mechanics, respectively, whereas painters had the highest prevalence of WMSDs in the lower back and feet (both at 15.4%). Logistic regression analysis showed that females were at higher risk of WMSDs than males (OR 5.027, [95% CI] [1.278-19.772], p < 0.05). Workers subjected to uncomfortable positions were at increased risk of WMSDs (OR 1.79, [95% CI] [1.333-2.410], p < 0.01). CONCLUSION: The prevalence of WMSDs is high among automotive maintenance workers, with the highest prevalence in the lower back (17.1%). Uncomfortable working postures and frequent repetitive movements with lower limbs and ankles at work may be important risk factors.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Masculino , Feminino , Humanos , Automóveis , Doenças Profissionais/etiologia , Doenças Profissionais/complicações , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Fatores de Risco , Estudos Epidemiológicos
8.
Ergonomics ; 66(12): 2212-2222, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36940236

RESUMO

We investigated the prevalence of work-related musculoskeletal symptoms (WMSs) among medical staff and evaluated the associations of different levels of adverse ergonomic factors with WMSs. A total of 6099 Chinese medical staff were asked to complete a self-reported questionnaire to assess the prevalence and risk factors of WMSs from June 2018 to December 2020. A prevalence rate of 57.5% was observed for WMSs among overall medical staffs, which mainly affected the neck (41.7%) and shoulder (33.5%). 'Keeping sitting for long hours very frequently' (OR = 1.26, 95% CI: 1.04, 1.53) was positively associated with WMSs in doctors, while 'keeping sitting for long hours occasionally' (OR = 0.91, 95% CI: 0.85, 0.97) was identified as a protective factor of WMSs in nurses. The associations of adverse ergonomic factors, organisational factors, and environmental factors with WMSs were different among medical staff in different positions.Practitioner summary: We conducted a multi-city study concerning the risk factors of WMSs by carrying out a face-to-face one-to-multiple questionnaire survey among medical staff in China. As a risk factor of WMSs in medical staff, adverse ergonomic factors should be paid more attention by the standard setting department and policy makers.Abbreviations: WMSDs: work-related musculoskeletal disorders; WMSs: work-related musculoskeletal symptoms; MSDs: musculoskeletal disorders; NMQ: Nordic Musculoskeletal Questionnaires; DMQ: Dutch Musculoskeletal Questionnaires; NIOSH: National Institute for Occupational Safety and Health; ORs: odds ratios.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Ergonomia , Inquéritos e Questionários , Fatores de Risco , Corpo Clínico , China/epidemiologia , Prevalência
9.
BMC Public Health ; 23(1): 10, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597111

RESUMO

OBJECTIVES: To describe the prevalence of self-reported musculoskeletal disorders among workers in the electronics manufacturing industry and to investigate the relations between work-related musculoskeletal disorders (WMSDs) and work-related variables. METHODS: An interview-based questionnaire survey was carried out in thirty electronics manufacturing factories in China in 2018. The prevalence of WMSDs was estimated using the modified Nordic Musculoskeletal Questionnaire (NMQ). A multivariate logistic regression model was applied to evaluate the effects of risk factors on WMSDs on multiple body parts. RESULTS: The 12-month prevalence of WMSDs among participants was 40.6%, and the common body sites affected were the neck (26.8%), shoulder (22.8%), upper back (14.9%), and lower back (14.8%). The results of logistic regression showed that female adults, > 5 job tenure and work-related factors (including awkward posture, lifting or carrying weights, excessive repetition, prolonged sitting, monotonous work and working under conditions of cold or temperature variations) led to a higher risk of WMSDs on most body parts. Upper back, wrist/hand and elbow pain levels were significantly higher for workers with vibration. However, more frequently, physical exercise was a protective factor against WMSDs on most body parts except the upper back, leg and knee. CONCLUSIONS: The study indicates a high prevalence of musculoskeletal pain among the electronics manufacturing industry in China. Different personal and work factors are related to the occurrence of WMSD on different body parts. Preventive measures should be implemented based on the characteristics of WMSD in the electronic manufacturing industry. Furthermore, the training and intervention guidance of ergonomic hazards in the workplace need to be strengthened by understanding the impact of bad posture, avoiding long-term sitting posture and increasing physical activities.


Assuntos
Doenças Musculoesqueléticas , Dor Musculoesquelética , Doenças Profissionais , Adulto , Humanos , Feminino , Prevalência , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Profissionais/prevenção & controle , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/prevenção & controle , Fatores de Risco , Inquéritos e Questionários , Dor Musculoesquelética/epidemiologia , Ergonomia , China/epidemiologia , Eletrônica
10.
Micromachines (Basel) ; 15(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38258199

RESUMO

As wide bandgap semiconductors, gallium nitride (GaN) lateral high-electron-mobility transistors (HEMTs) possess high breakdown voltage, low resistance and high frequency performance. PGaN gate HEMTs are promising candidates for high-voltage, high-power applications due to the normally off operation and robust gate reliability. However, the threshold and gate-breakdown voltages are relatively low compared with Si-based and SiC-based power MOSFETs. The epitaxial layers and device structures were optimized to enhance the main characteristics of pGaN HEMTs. In this work, various methods to improve threshold and gate-breakdown voltages are presented, such as the top-layer optimization of the pGaN cap, hole-concentration enhancement, the low-work-function gate electrode, and the MIS-type pGaN gate. The discussion of the main gate characteristic enhancement of p-type GaN gate HEMTs would accelerate the development of GaN power electronics to some extent.

11.
Front Public Health ; 10: 1047814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504943

RESUMO

Objective: This study investigated the prevalence of wrist injuries in 15 industries and different types of work in China. Study on the associated factors of wrist injuries provides a scientific basis for prevention and treatment of wrist diseases in occupational workers. Methods: A cross-sectional study of musculoskeletal symptoms of related practitioners in 15 industries, including automobile manufacturing, was conducted to retrieve worker demographic information, working wrist posture, and pain conditions. Multivariable binary logistic regression analyses were performed to identify factors associated with work-related musculoskeletal disorders (WMSDs). Results: The prevalence of wrist injuries among the study population was 13.2%. Toy manufacturing, animal husbandry, automobile manufacturing, shoe manufacturing, and biopharmaceutical manufacturing had the highest wrist injury rates at 29.1, 19.1, 14.9, 14.9, and 14.0%, respectively. Among the types of jobs, enamel workers (63.0%), butchers (43.6%), combers (32.5%), welders (31.3%), and scaffolders (26.5%) had the highest prevalence rates. Based on the final multivariate logistic regression analysis: female [odds ratios (OR) = 1.24; 95% confidence interval (CI), 1.15-1.35], 6-10 years of service (OR = 1.11; 95% CI, 1.03-1.18), >10 years of service (OR = 1.15; 95% CI, 1.06-1.25), frequent upward and downward flexion in wrist posture at work (OR = 1.81; 95% CI, 1.84-2.11), and frequent wrist placement on the edge of angular objects increased the OR of injury (OR = 1.52; 95% CI, 1.44-1.61). Need to squeeze objects tightly while working (OR = 1.72; 95% CI, 1.57-1.89), prolonged wrist flexion (OR = 1.86; 95% CI, 1.75-1.97), and work hand position above the shoulder for prolonged periods (OR = 1.11; 95% CI, 1.04-1.19) also suggested the relationship between these factors and the higher prevalence of wrist injury in the workers. The associated factor was physical activity (OR = 0.86; 95% CI, 0.80-0.94). Conclusion: This study suggested the relationship between these factors and the higher prevalence of wrist injury in the toy manufacturing, animal husbandry, automobile manufacturing, and shoe-making industries, enamel workers, butchers, and combers. And are work types that require special attention. Females, working age, physical activity, and abnormal posture of the wrist were factors significantly associated with WMSDs.


Assuntos
População do Leste Asiático , Traumatismos do Punho , Feminino , Humanos , Animais , Estudos Transversais , Traumatismos do Punho/epidemiologia , Prevalência , Povo Asiático
12.
BMC Musculoskelet Disord ; 23(1): 952, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329459

RESUMO

BACKGROUND: Changes in modern industrial production practices can easily lead to shoulder work-related musculoskeletal disorders (WMSD). The current reports on shoulder WMSD are limited to some industries are less well studied, and the sample size is usually small. This study aimed to describe the prevalence and severity of shoulder WMSD in a large sample of Chinese workers from 15 industries, analyze the possible correlations with sociodemographic and work-related variables, and compare the differences between industries. METHODS: A cross-sectional study was conducted among a sample of 55,749 participants from 252 enterprises in 15 industries throughout China. A Chinese version of the musculoskeletal disease questionnaire was used to collect the demographic factors, shoulder symptoms in past 12 months, and work-related factors including posture-related factors, repetition, vibration, work organization, job control, and environmental factors as independent variables. Descriptive statistics were used, and the binary logistic regression analysis was performed to explore the association between shoulder WMSD and potential demographic and work-related factors. RESULTS: Nearly 35.5% of participants reported shoulder pain and discomfort in the previous 12 months. Biopharmaceutical manufacturing (56.2%), medical services (54.4%), and aviation services (50.1%) were the three industries with the highest prevalence of shoulder WMSD. The pain score of aviation services workers was the highest. The related factors for shoulder WMSD varied among the different industries. CONCLUSION: Our study found a relatively high prevalence of shoulder WMSD in China. There were large differences in the prevalence of shoulder WMSD among industries, and the related factors were particular to each industry. Such information is useful to help occupational health practitioners and policymakers conduct preventive programs to reduce shoulder disorders in these working populations.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Estudos Transversais , Ombro , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Doenças Musculoesqueléticas/diagnóstico , Doenças Musculoesqueléticas/epidemiologia , Prevalência , Inquéritos e Questionários , China/epidemiologia , Fatores de Risco
13.
Artigo em Inglês | MEDLINE | ID: mdl-36361315

RESUMO

OBJECTIVE: This study aims to investigate the one-year prevalence and the associated factors of work-related musculoskeletal disorders (WMSDs) among furniture manufacturing workers in Guangdong, China. METHODS: A cross-sectional study of 4181 (2953 males and 1228 females) furniture manufacturing workers was conducted between September 2019 and December 2019. All information about WMSDs was collected by the electronic version of Chinese Musculoskeletal Questionnaires (CMQ). Descriptive statistics and a binary logistic regression model were used to interpret the data. RESULT: The overall prevalence of WMSDs was 31.57%. The WMSD symptoms most commonly occurred in the neck (16.77%), followed by the shoulders (14.90%), ankles/feet (14.64%), hands/wrists (13.30%), upper back (11.48%), and lower back (10.95%). Multiple logistic regression analysis revealed that several individual, labor organization, and ergonomics-related factors conferred significant risks to WMSDs at different body sites. CONCLUSIONS: WMSDs remain the major occupational health problem for furniture manufacturing workers. Hence, some effective and feasible protective measures for furniture manufacturing workers are required in order to alleviate the health burden caused by WMSDs.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Masculino , Feminino , Humanos , Estudos Transversais , Prevalência , Decoração de Interiores e Mobiliário , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/complicações , Fatores de Risco , Inquéritos e Questionários
14.
Artigo em Inglês | MEDLINE | ID: mdl-36293896

RESUMO

BACKGROUND: With the development of the electronics manufacturing industry, the demand for human resources has increased, which has also led to the frequent occurrence of multi-site work-related musculoskeletal disorders. METHOD: The participants (n = 7307) were recruited from 30 enterprises in China in 2018. The prevalence of musculoskeletal disorders was estimated using a modified Chinese version of the Musculoskeletal Disorders Questionnaire. The multivariate logistic regression model was applied to evaluate the effects of risk factors on multi-site musculoskeletal symptoms. Additionally, the log-binomial model was established to examine the correlation between the various sites of musculoskeletal symptoms in the body. RESULTS: The 12-month prevalence of musculoskeletal symptoms among participants was 40.6%. The proportion of musculoskeletal symptoms involving single-site and 2/>2 body sites were 11.6% and 29.0%, respectively. The results of logistic regression showed that female adults who smoked, had >5-year job tenure, and always stood or sat for long period at work had a higher risk in 2/>2 body sites of musculoskeletal symptoms (p < 0.05). However, physical exercise during leisure time and "Squatting or kneeling for long period at work" were more frequently protective factors. Furthermore, the log-binomial model indicated that the neck and shoulder were significantly related to each other (Prevalence Ratio, PR: 5.511 and 7.017). CONCLUSIONS: Several demographic characteristics and work-related factors were associated with multi-site musculoskeletal symptoms in the electronics manufacturing industry in China. Improving the levels of physical exercise and reducing posture problems and force loads may help to promote the health of workers.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Adulto , Feminino , Humanos , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Doenças Musculoesqueléticas/etiologia , Doenças Musculoesqueléticas/complicações , Prevalência , China/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Eletrônica , Indústria Manufatureira
15.
Nanomaterials (Basel) ; 12(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080047

RESUMO

Searching for low-cost and highly-efficient oxygen reduction reaction (ORR) catalysts is crucial to the large-scale application of fuel cells. Herein, by means of density functional theory (DFT) computations, we proposed a new class of ORR catalysts by doping the CrS2 monolayer with non-metal atoms (X@CrS2, X = B, C, N, O, Si, P, Cl, As, Se, and Br). Our results revealed that most of the X@CrS2 candidates exhibit negative formation energy and large binding energy, thus ensuring their high stability and offering great promise for experimental synthesis. Moreover, based on the computed free energy profiles, we predicted that N@CrS2 exhibits the best ORR catalytic activity among all considered candidates due to its lowest overpotential (0.41 V), which is even lower than that of the state-of-the-art Pt catalyst (0.45 V). Remarkably, the excellent catalytic performance of N@CrS2 for ORR can be ascribed to its optimal binding strength with the oxygenated intermediates, according to the computed linear scaling relationships and volcano plot, which can be well verified by the analysis of the p-band center as well as the charge transfer between oxygenated species and catalysts. Therefore, by carefully modulating the incorporated non-metal dopants, the CrS2 monolayer can be utilized as a promising ORR catalyst, which may offer a new strategy to further develop eligible electrocatalysts in fuel cells.

16.
Nanoscale ; 14(32): 11684-11692, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35912887

RESUMO

2D imidazole MOFs are considered to be ideal carbon precursors for oxygen reduction reactions owing to their adjustable ligand components and durable coordination mode. Due to the massive electron delocalization in the lamella, the conjugative effect among 2D MOF layers immensely restricts the exposure of catalytic sites after carbonization, which makes the decoupling layer extremely important on the premise of ensuring activity. Herein, atomic thickness ultra-thin zinc-imidazole MOF precursors were prepared through a bottom-up ligand regulated strategy to achieve the aim of lamellar decoupling. The introduction of heterologous ligands excites stable delocalized electrons, resulting in a decrease in the interlayer force of 2D zinc-imidazole MOF precursors. Subsequent salt template-supported ammonia pyrolysis assisted the MOF-derived carbon sheets to grow along the transverse direction and optimize pore size distribution as did the doping nitrogen type. The MOF-derived carbon sheets demonstrated increasing mesopores and fringe graphitic N which could significantly promote the mass transfer and electron transfer speed during the oxygen reduction reaction. In addition, the obtained ultra-thin carbon delivered an outstanding onset potential (0.98 V vs. RHE) and durability (retaining 91% of the initial current after 12000 s of operation), showing tremendous commercial prospects in sustainable energy.

17.
BMC Public Health ; 22(1): 1493, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931976

RESUMO

BACKGROUND: With the acceleration of industrialization and population aging, low back pain (LBP) has become the leading cause of life loss years caused by disability. Thus, it places a huge economic burden on society and is a global public health problem that needs urgent solution. This study aimed to conduct an epidemiological investigation and research on a large sample of workers in key industries in different regions of China, determine the incidence and distribution characteristics of LBP, explore the epidemic law, and provide a reference basis for alleviating global public health problems caused by LBP. METHODS: We adopted a modified epidemiological cross-sectional survey method and a stratified cluster sampling method. All on-duty workers who fulfill the inclusion criteria are taken as the research participants from the representative enterprises in key industries across seven regions: north, east, central, south, southwest, northwest, and northeast China. The Chinese version of the musculoskeletal disease questionnaire, modified by a standardized Nordic questionnaire, was used to collect information, and 57,501 valid questionnaires were received. Descriptive statistics were used, and multivariate logistic regression analysis (p < 0.05) was performed to explore the association between musculoskeletal disorders and potential risk factors. RESULTS: LBP annual incidence among workers in China's key industries is 16.4%. There was a significant difference in LBP incidence among occupational groups across different industries (p < 0.05). The multivariate regression model showed the following as risk factors for LBP: frequent repetitive movements with the trunk, working in the same positions at a high pace, trunk position, frequently turning around with your trunk, often working overtime, lifting heavy loads (i.e., more than 20 kg), education level, staff shortage, working age (years), cigarette smoking, use of vibration tools at work, body mass index, lifting heavy loads (i.e., more than 5 kg), and age (years). Physical exercise, often standing at work, and absolute resting time were protective factors. CONCLUSION: LBP incidence among key industries and workers in China is high. Thus, it is urgent to take relevant measures according to the individual, occupational, and psychosocial factors of LBP to reduce the adverse impact of LBP on workers' health.


Assuntos
Dor Lombar , Doenças Profissionais , China/epidemiologia , Estudos Transversais , Humanos , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Doenças Profissionais/etiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários
18.
Nanoscale ; 14(18): 6902-6911, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35446333

RESUMO

The development of highly efficient bifunctional electrocatalysts to boost oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly desirable for energy conversion and storage devices. Herein, by means of comprehensive first-principles computations, we systematically explored the catalytic activities of a series of single transition metal atoms anchored on two-dimensional VS2 monolayers (TM@VS2) for ORR/OER. Our results revealed that Ni@VS2 exhibits low overpotentials for both ORR (0.45 V) and OER (0.31 V), suggesting its great potential as a bifunctional catalyst, which is mainly induced by its moderate interaction with oxygenated intermediates according to the established scaling relationship and volcano plot. Interestingly, the substituted doping of nitrogen heteroatoms into the VS2 substrate can further effectively improve the ORR/OER activity of the active metal atom to achieve more eligible ORR/OER bifunctional catalysts. Our results not only propose a new class of potential bifunctional oxygen catalysts but also offer a feasible strategy for further tuning their catalytic activity.

19.
J Colloid Interface Sci ; 607(Pt 1): 1-15, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34500412

RESUMO

The intracellular O2-supply not only can relieve tumor hypoxia but also enhance the effects of photodynamic therapy (PDT). In this work, metallic Mo2C@N-carbon@PEG nanoparticles were constructed to reveal the near infrared (NIR)-photocatalytic O2 generation and promote photodynamic therapy (PDT). Here, (NH4)6Mo7O24·4H2O nanorods and urea were adopted as resources that were calcined to obtain Mo2C@N-carbon nanoparticles (20 nm). All samples displayed high NIR absorption as well as photothermal conversion efficiency of up to 52.7 % (Mo2C@N-Carbon-3@PEG). The density functional theory calculations demonstrated the metallic characteristic of Mo2C and that the consecutive interband/intraband charge-transition was responsible for the high NIR harvest and redox ability of electron-hole pairs, making the NIR-photocatalytic O2 and reactive oxygen species (ROS) generation. In comparison with the pure Mo2C, the heterostructure displayed twice the performance due to the enhanced charge-segregation between Mo2C and N-carbon. Given the high X-ray absorption coefficient and photothermal ability, the nanocomposite could be used in novel computer tomography and photothermal imaging contrast. Furthermore, the novel biodegradation and metabolism behaviors of nanocomposites were investigated, which were reflected as elimination from the body (mouse) via feces and urine within 14 days. The as-synthesized Mo2C@N-Carbon@PEG nanocomposites integrated the dual-model imaging, intracellular O2-supply, and phototherapy into one nanoplatform, revealing its potential for anti-cancer therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Carbono , Linhagem Celular Tumoral , Camundongos , Molibdênio , Neoplasias/tratamento farmacológico , Oxigênio , Fototerapia
20.
China CDC Wkly ; 4(50): 1123-1130, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36751559

RESUMO

What is already known about this topic?: The burden of illness and economic losses due to upper-limb work-related musculoskeletal disorders (UL-WMSDs) is high; thus, they have become a major global public health problem. At present, the epidemiological characteristics of UL-WMSDs in China's occupational population are still unknown. What is added by this report?: The incidence of UL-WMSDs among key occupational groups in China is 22.5%, with distinct occupational characteristics. What are the implications for public health practice?: This study has primarily determined the occurrence and potential risk factors of UL-WMSDs in key industries in China and provided data support for recommending prevention and control of the occurrence of such diseases in key industries in China, and in facilitating the addition into the China's List of Legal Occupational Diseases.

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