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1.
Int J Occup Saf Ergon ; 28(1): 659-671, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32321377

RESUMO

Introduction. This study aimed to perform an in-depth analysis of a catastrophic coach crash that occurred on the Chinese expressway, and thus draw useful lessons to avoid similar mistakes. Methods. Various causes were identified from the investigation report based on a proposed accident causation model, which provides a universal pathway for accident analysis from the individual level to the organizational level. Results. Driver error in an emergency affected by fatigue and speeding led directly to the crash. Accordingly, drivers in coaches should be monitored effectively and their unsafe acts must be corrected in a timely manner to avoid the formation of unsafe habits. Based on individual flaws, weaknesses in the construction of the organizational safety management system and safety culture were further deduced and discussed. Conclusion. The work and rest system, as well as the dynamic monitoring system for drivers, should be perfected strictly according to the regulations. Additionally, external factors regarding deficiencies in the design and management of the expressway and the supervision of the transportation company also had great impact on this crash. In summary, more efforts should be taken regarding root causes at the organizational level, regardless of internal or external factors.


Assuntos
Condução de Veículo , Veículos Automotores , Acidentes , Acidentes de Trânsito , Humanos , Gestão da Segurança/métodos , Meios de Transporte
2.
Front Public Health ; 10: 790436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433603

RESUMO

Background: Advanced maternal age is associated with fetal outcomes such as higher risks of birth defects and very low birth weight. Off-farm employment is an important factor in fertility transition in many developing countries. This study investigated the association between off-farm employment and fertility timing among Chinese rural women. Method: Using data from the China Labor-force Dynamics Survey (CLDS), we employed the ordinary least squares and instrumental variable approaches to estimate the effect of female off-farm employment on fertility timing decisions as well as the differences in the effect across groups. Results: The results show that off-farm employment participation is significantly associated with a later age at first birth, and the effect is stronger for women participating in wage employment than in off-farm self-employment. The delayed effects on fertility timing are also more pronounced for less-educated women and low-income families, implying a heterogeneous effect in terms of women's socioeconomic status. Conclusion: Studies of the relationship between women's off-farm employment and fertility timing in rural areas of developing countries remain limited. This study provides important insights on this topic, and it lends support to efforts to design effective policies and practices to facilitate female employment, childbearing, and health promotion.


Assuntos
Países em Desenvolvimento , Fertilidade , Demografia , Escolaridade , Emprego , Fazendas , Feminino , Humanos , Dinâmica Populacional , Fatores Socioeconômicos
3.
Chemosphere ; 298: 134136, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35276105

RESUMO

Facing the great challenge that the increasing solid waste fly ash is difficult to treat and utilize properly, this paper reports a class of novel low-cost fly ash porous materials with high interconnected porosity fabricated by a facile foaming process. On this basis, composites with multiscale pore structures from the nanometer to macroscopic scale were designed and constructed by decorating layered double hydroxide (LDH) onto the inner channel surface. Such porous materials with 3D through-hole structures showed high interconnected porosity (up to 77.61%), suitable compressive strength (up to 23.79 MPa) and significant water permeation flux (549.86 m3∙m-2∙h-1 at 0.1 MPa). Moreover, the adsorption effect of dosage, initial concentration, pH, temperature and contact time on Congo red (CR) from simulated wastewater was investigated. The composites exhibited a good adsorption efficiency of ∼100% and adsorption capacities of 45.79 mg/g. The adsorption kinetic can be explained well by the pseudosecond-order kinetic equation and isotherm adsorption followed Langmuir isotherm model. This suggests that low-cost and eco-friendly fly ash composites have potential applications in industrial-scale wastewater treatment. This work also provides a general strategy to design and utilize fly ash porous materials for filtration and adsorption.


Assuntos
Cinza de Carvão , Poluentes Químicos da Água , Adsorção , Carvão Mineral , Vermelho Congo , Porosidade , Poluentes Químicos da Água/análise
4.
Membranes (Basel) ; 12(11)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36422156

RESUMO

Conventional hydrophobic membrane-based membrane distillation (MD) has been applied for ammonia recovery from an anaerobic digestion (AD) effluent. However, the typical hydrophobic membranes do not have selectivity for ammonia and water vapor, which results in high energy consumption from the water evaporation. To enhance the selectivity during the ammonia recovery process, the functionalized carbon nanotubes (CNTs)/polyvinylidene fluoride (PVDF) nanofiber membranes were fabricated by electrospinning, and the effects of different CNTs and their contents on the performance of nanofiber membranes were investigated. The results indicate that CNTs can be successfully incorporated into nanofibers by electrospinning. The contact angles of the composite membrane are all higher than those of commercial membrane, and the highest value 138° can be obtained. Most importantly, under the condition of no pH adjustment, the ammonia nitrogen transfer coefficient reaches the maximum value of 3.41 × 10-6 m/s, which is about twice higher than that of commercial membranes. The ammonia separation factor of the carboxylated CNT (C-CNT) composite membrane is higher than that of the hydroxylated CNT(H-CNT) composite membrane. Compared with the application of the novel C-CNT composite membrane, the ammonia separation factor is 47% and 25% higher than that of commercial and neat PVDF membranes. This work gives a novel approach for enhancing ammonia and water selectivity during AD effluent treatment.

5.
Chemosphere ; 304: 135318, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35709833

RESUMO

It is an urgent need to develop new environmentally friendly spinel ferrites with high catalytic efficiency. In this work, a series of Mg-Fe-Al-O spinels with different ratios of Mg/Al were successfully synthesized by the reaction sintering method and were used as a heterogeneous photo-Fenton catalyst for degradation of Rhodamine B (RhB). The effect of different ratios of Mg/Al on the properties of Mg-Fe-Al-O spinel was characterized and analyzed through a range of advanced characterization techniques and DFT calculations. The influence factors on the photo-Fenton reaction catalyzed by Mg-Fe-Al-O spinels were systematically investigated. The results showed that the prepared Mg-Fe-Al-O spinels had larger lattice parameters, wider bandgap, and stronger magnetism, with the Mg content increased. Among them, Mg-9 (Mg0.88Fe1.88Al0.23O4) had the best catalytic performance in the photo-Fenton reaction. The degradation efficiency of RhB reached 98.45%, and the TOC removal efficiency was 83.47%. The elemental valence and PDOS of Mg-9 (Mg0.88Fe1.88Al0.23O4) spinels were closer to MgFe2O4. The photo-generated holes could directly oxidize water and hydroxyl to generate reactive oxygen species ·OH, improving the catalytic activity.


Assuntos
Peróxido de Hidrogênio , Ferro , Óxido de Alumínio , Catálise , Óxido de Magnésio , Rodaminas
6.
Artigo em Inglês | MEDLINE | ID: mdl-33917131

RESUMO

Major accidents occurred frequently in the road transportation industry, and the resulting harm to drivers, property loss, and traffic interruption are very serious. This study investigated 11 particularly major accidents involving commercial vehicles in China, and performed analysis on accident characteristics regarding the time, location, types of vehicles, and accident causation at different levels based on the 24Model. Large buses and dangerous goods vehicles were involved in 10 accidents and they all occurred on a freeway. The months from May to August, especially during the time periods of 2:00-4:00 and 14:00-16:00 every day, were the most prone to accidents. The driver's speeding and fatigued driving, and vehicle failure were the direct causes of most of the accidents. The defects in organizational safety management involved 12 system elements, such as safety accountability, education and training, etc. Procedures are of no use if they were not followed, and there was often no effective process to assess the implementation of procedures in many organizations. The weaknesses in organizational safety culture were the source of accidents, which was mainly manifested in members' inadequate cognition of key elements in the aspects of safety importance, safety commitment, safety management system, etc. Understanding the characteristics and root causes of accidents can help to prevent the recurrence of similar mistakes and strengthen preventative measures in road transportation enterprises.


Assuntos
Acidentes de Trânsito , Condução de Veículo , China/epidemiologia , Veículos Automotores , Meios de Transporte
7.
Artigo em Inglês | MEDLINE | ID: mdl-31382352

RESUMO

An improved accident causation model which demonstrates the relationships among different causal factors was proposed in this study. It provides a pathway for accident analysis from the individual level to the organizational level. Unsafe acts and conditions determined by individuals' poor safety knowledge, low safety awareness, bad safety habits, etc. are the immediate causes of an accident. Deficiencies in safety management systems and safety culture remain the root causes, which can cause consequences at the individual level. Moreover, the weaknesses of an organization's safety culture can have a great impact on the formation of a good safety climate and can further lead to poor decision-making and implementation of procedures in the safety management system. In order to contribute to a better perception and understanding of the accident causation model, one typical case in the process industry, the oil leak and explosion of the Sinopec Donghuang pipelines, was selected for this study. The causality from immediate causes to root causes is demonstrated in sequence and can be shown in this model explicitly and logically. Several important lessons are summarized from the results and targeted measures can be taken to avoid similar mistakes in the future. This model provides a clear and resourceful method for the safety and risk practitioner's toolkit in accident investigation and analysis, and the organization can use it as a tool to conduct staff trainings and thus to keep accidents under control.


Assuntos
Acidentes , Modelos Organizacionais , Humanos , Indústrias , Gestão da Segurança/métodos
8.
Artigo em Inglês | MEDLINE | ID: mdl-27869654

RESUMO

Introduction: Senior managers' attitudes towards safety are very important regarding the safety practices in an organization. The study is to describe the current situation of senior managers' attitudes towards safety in the Chinese coal industry. Method: We evaluated the changing trends as well as the reasons for these changes in the Chinese coal industry in 2009 and in 2014 with 168 senior manager samples from large Chinese state-owned coal enterprises. Evaluations of 15 safety concepts were performed by means of a questionnaire. Results and Conclusions: Results indicate that, in 2014, three concepts were at a very high level (mean > 4.5), and six were at a relatively high level (4.5 > mean > 4.0). Analyses of changing trends revealed that nine concepts improved significantly, while four greatly declined in 2014 compared to those in 2009. The data reported here suggest that the reasons for the significant improvement with respect to the nine concepts include the improvement in social and legal environments, the improvement of the culture of social safety, workers' safety demands being met, and scientific and technical advances in the coal industry. The decline of the four concepts seemed to be caused by a poor awareness of managers in the coal industry that safety creates economic benefits, insufficient information on safety, inadequate attention to the development of a safety culture and safety management methods, and safety organizations and workers' unions not playing their role effectively. Practical Applications: We therefore recommend strengthening the evidence that safety creates economic benefits, providing incentives for employees to encourage their participation in safety management, and paying more attention to the prevention of accidents in coal mines via safety organizations and unions. These results can provide guidelines for workers, industrialists, and government regarding occupational safety in the whole coal industry.


Assuntos
Pessoal Administrativo/psicologia , Atitude Frente a Saúde , Indústria do Carvão Mineral/normas , Minas de Carvão/normas , Saúde Ocupacional/normas , Gestão da Segurança/normas , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
9.
Sci Rep ; 5: 18187, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26655843

RESUMO

Irreversible electroporation (IRE) is a novel ablation method that has been tested in humans with lung, prostate, kidney, liver, lymph node and presacral cancers. As a new non-thermal treatment, the use of IRE to ablate tumors in the musculoskeletal system might reduce the incidence of fractures. We aimed to determine the ablation threshold of cortical bone and to evaluate the medium- and long-term healing process and mechanical properties of the femur in a rabbit model post-IRE ablation. The ablation threshold of cortical bone was between 1090 V/cm and 1310 V/cm (120 pulses). IRE-ablated femurs displayed no detectable fracture but did exhibit signs of recovery, including osteoblast regeneration, angiogenesis and bone remodeling. In the ablation area, revascularization appeared at 4 weeks post-IRE. Osteogenic activity peaked 8 weeks post-IRE and remained high at 12 weeks. The mechanical strength decreased briefly 4 weeks post-IRE but returned to normal levels within 8 weeks. Our experiment revealed that IRE ablation preserved the structural integrity of the bone cortex, and the ablated bone was able to regenerate rapidly. IRE may hold unique promise for in situ bone tissue ablation because rapid revascularization and active osteogenesis in the IRE ablation area are possible.


Assuntos
Técnicas de Ablação , Eletroporação/métodos , Fêmur/cirurgia , Técnicas de Ablação/efeitos adversos , Animais , Fenômenos Biomecânicos , Fêmur/irrigação sanguínea , Fêmur/diagnóstico por imagem , Fêmur/lesões , Fêmur/patologia , Fenômenos Mecânicos , Modelos Animais , Neovascularização Fisiológica , Coelhos , Radiografia , Cicatrização
10.
PLoS One ; 10(6): e0131404, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26114962

RESUMO

BACKGROUND: To evaluate the potential effects of irreversible electroporation ablation on the Achilles tendon in a rabbit model and to compare the histopathological and biomechanical changes between specimens following electroporation ablation and radiofrequency ablation. METHODS: A total of 140 six-month-old male New Zealand rabbits were used. The animals were randomly divided into two groups, 70 in the radiofrequency ablation group and 70 in the electroporation group. In situ ablations were applied directly to the Achilles tendons of rabbits using typical electroporation (1800 V/cm, 90 pulses) and radiofrequency ablation (power control mode) protocols. Histopathological and biomechanical evaluations were performed to examine the effects of electroporation ablation and radiofrequency ablation over time. RESULTS: Both electroporation and radiofrequency ablation produced complete cell ablation in the target region. Thermal damage resulted in tendon rupture 3 days post radiofrequency ablation. In contrast, electroporation-ablated Achilles tendons preserved their biomechanical properties and showed no detectable rupture at this time point. The electroporation-ablated tendons exhibited signs of recovery, including tenoblast regeneration and angiogenesis within 2 weeks, and the restoration of their integral structure was evident within 12 weeks. CONCLUSIONS: When applying electroporation to ablate solid tumors, major advantage could be that collateral damage to adjacent tendons or ligaments is minimized due to the unique ability of electroporation ablation to target the cell membrane. This advantage could have a significant impact on the field of tumor ablation near vital tendons or ligaments.


Assuntos
Técnicas de Ablação/efeitos adversos , Tendão do Calcâneo , Eletroporação/métodos , Tendão do Calcâneo/lesões , Tendão do Calcâneo/patologia , Tendão do Calcâneo/fisiopatologia , Animais , Fenômenos Biomecânicos , Masculino , Modelos Animais , Neoplasias/cirurgia , Neovascularização Fisiológica , Coelhos , Ruptura
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