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1.
Small ; 19(42): e2304269, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37317038

RESUMEN

All-solid-state lithium batteries have been developed to secure safety by substituting a flammable liquid electrolyte with a non-flammable solid electrolyte. However, owing to the nature of solids, interfacial issues between cathode materials and solid electrolytes, including chemical incompatibility, electrochemo-mechanical behavior, and physical contact, pose significant challenges for commercialization. Herein, critical factors for understanding the performance of all-solid-state batteries in terms of solid interfaces and non-zero lattice strains are identified through a strategic approach. The initial battery capacity can be increased via surface coating and electrode-fabrication methods; however, the increased lattice strain causes significant stress to the solid interface, which degrades the battery cycle life. However, this seesaw effect can be alleviated using a more compacted electrode microstructure between the solid electrolyte and oxide cathode materials. The compact solid interfaces contribute to low charge-transfer resistance and a homogeneous reaction between particles, thereby leading to improved electrochemical performance. These findings demonstrate, for the first time, a correlation between the uniformity of the electrode microstructure and electrochemical performance through the investigation of the reaction homogeneity among particles. Additionally, this study furthers the understanding of the relationship between electrochemical performance, non-zero lattice strain, and solid interfaces.

2.
J Korean Med Sci ; 38(37): e284, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37724493

RESUMEN

BACKGROUND: Occupational injuries and diseases are life events that significantly impact an individuals' identity. In this study, we examined the trajectories of self-esteem among victims of occupational injury and disease and their relation to health. METHODS: The Panel Study of Workers' Compensation Insurance conducted annual follow-ups on workers who had experienced occupational injury or disease. A total of 2,000 participants, who had completed medical care, were followed from 2013 to 2017. Growth mixture modeling was utilized to identify latent classes in the self-esteem trajectory. Additionally, logistic regressions were conducted to explore the association between trajectory membership, baseline predictors, and outcomes. RESULTS: Three distinct trajectory classes were identified. Total 65.8% of the samples (n = 1,316) followed an increasing self-esteem trajectory, while 31.1% (n = 623) exhibited a constant trajectory, and 3.1% (n = 61) showed a decreasing trajectory. Individuals with an increasing trajectory were more likely to have a higher educational attainment (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.20-2.88), an absence of a moderate-to-severe disability rating (OR, 0.49; 95% CI, 0.25-0.96), no difficulty in daily living activities (OR, 0.81; 95% CI, 0.75-0.88), and were economically active (re-employed: OR, 2.46; 95% CI, 1.52-3.98; returned to original work: OR, 4.46; 9% CI, 2.65-7.50). Those with a decreasing self-esteem trajectory exhibited an increased risk of poor subjective health (OR, 1.89; 95% CI, 0.85-4.85 in 2013 to OR, 3.17; 95% CI, 1.04-13.81 in 2017), whereas individuals with an increasing trajectory showed a decreased risk (OR, 0.54; 95% CI, 0.43-0.68 in 2013 to OR, 0.44; 95% CI, 0.33-0.57 in 2017). CONCLUSION: Our findings emphasize the diversity of psychological responses to occupational injury or disease. Policymakers should implement interventions to enhance the self-esteem of victims.


Asunto(s)
Seguro , Traumatismos Ocupacionales , Humanos , Autoevaluación Diagnóstica , Indemnización para Trabajadores , Actividades Cotidianas
3.
Chem Rev ; 120(14): 6934-6976, 2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32101429

RESUMEN

To advance current Li rechargeable batteries further, tremendous emphasis has been made on the development of anode materials with higher capacities than the widely commercialized graphite. Some of these anode materials exhibit capacities above the theoretical value predicted based on conventional mechanisms of Li storage, namely insertion, alloying, and conversion. In addition, in contrast to conventional observations of loss upon cycling, the capacity has been found to increase during repeated cycling in a significant number of cases. As the internal environment in the battery is very complicated and continuously changing, these abnormal charge storage behaviors are caused by diverse reactions. In this review, we will introduce our current understanding of reported reactions accounting for the extra capacity. It includes formation/decomposition of electrolyte-derived surface layer, the possibility of additional charge storage at sharp interfaces between electronic and ionic sinks, redox reactions of Li-containing species, unconventional activity of structural defects, and metallic-cluster like Li storage. We will also discuss how the changes in the anode can induce capacity increase upon cycling. With this knowledge, new insights into possible strategies to effectively and sustainably utilize these abnormal charge storage mechanisms to produce vertical leaps in performance of anode materials will be laid out.

4.
J Environ Manage ; 324: 116345, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36191499

RESUMEN

Pharmaceutical products (PPs) are emerging water pollutants with adverse environmental and health-related impacts, owing to their toxic, persistent, and undetectable microscopic nature. Globally, increasing scientific knowledge and advanced technologies have allowed researchers to study PP-associated problems and their removal for water reuse. Experimental modeling methods require laborious, lengthy, expensive, and environmentally hazardous lab-work to optimize the process. On the other hand, predictive machine learning (ML) models can trace the complex input-output relationship of a process using available datasets. In this study, ensemble ML techniques, including decision tree (DT), random forest (RF), and Xtreme gradient boost (XGB), were used to explore PP (diclofenac, iopromide, propranolol, and trimethoprim) removal by a managed aquifer recharge (MAR) system. The model input parameters included characteristics of reclaimed water and soil used in the columns, pH, dissolved organic carbon, operating time, nitrogen dioxide, sulfate, nitrate, electrical conductivity, manganese, and iron. The selected PP removal was the model output. Datasets were collected through a one-year experimental study of continuous MAR system operation to predict the removal of PPs. DT, RF, and XGB models were then developed for one of the selected compounds and tested for the others to check the reliability of the ML model results. The developed models were assessed using statistical performance matrices. The experimental results showed >80% removal of propranolol and trimethoprim; however, removal of diclofenac and iopromide was only ≈50% by the MAR system. The proposed DT and RF models presented higher coefficients of determination (R2 ≥ 0.92) for diclofenac, propranolol, and trimethoprim than for iopromide (R2 ≤ 0.63). In contrast, the XGB model showed better results for diclofenac, iopromide, propranolol, and trimethoprim, with R2 values of 0.92, 0.72, 0.96, and 0.97, respectively. Therefore, XGB could be the best predictive model to provide insight into the adaptation of ML models to predict PP removal by the MAR system, thereby minimizing experimental work.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Diclofenaco , Propranolol , Reproducibilidad de los Resultados , Contaminantes Químicos del Agua/análisis , Agua Subterránea/química , Trimetoprim , Agua , Preparaciones Farmacéuticas
5.
Small ; 16(41): e2003688, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32964623

RESUMEN

Sodium-ion batteries (SIBs) have become increasingly important as next-generation energy storage systems for application in large-scale energy storage. It is very crucial to develop an eco-friendly and green SIB technique with superior performance for sustainable future use. Replacing the conventional inorganic electrode materials with green and safe organic electrodes will be a promising approach. However, the poor electrochemical kinetics, unstable electrode-electrolyte interface, high solubility of the electrodes in the electrolyte, and large amount of conductive carbon present great challenges for organic SIBs. In this study, the issues of organic electrodes are addressed through atomic-level manipulation of these organic molecules using a series of ultrathin (Å-level) metal oxide coatings (Al2 O3 , ZnO, and TiO2 ). Uniform and precise coatings on the perylene-3,4,9,10-tetracarboxylicacid dianhydride by gas-phase atomic layer deposition technique shows a stable interphase, enhanced electrochemical kinetics (71C, 10 A g-1 ), and excellent stability (89%-500 cycles) compared to conventional organic electrode (70%-200 cycles). Further studies reveal that the chemical stability of the metal oxide coating layer plays a critical role in influencing the redox behavior, and improving kinetics of organic electrodes. This study opens a new avenue for developing high-energy organic SIBs with performance equivalent to inorganic counterparts.

6.
Small ; 16(5): e1905875, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31943743

RESUMEN

The anionic redox chemistries of layered cathode materials have been in focus recently due to an intriguing phenomenon that cannot be described by the number of electrons of transition metal ions. However, even though several studies have investigated the anionic redox chemistry of layered materials in terms of the charge compensation, the relationship between the origin of the structural behavior and anionic redox chemistry in layered materials remains poorly understood. In addition, a simultaneous redox process of transition metal ions could occur through the d bands interaction. Here, it is demonstrated that the anionic redox chemistry is associated with the anisotropic structural behavior of the layered cathode materials albeit without providing additional capacities exceeding the theoretical values. These findings will provide a foundation of a new chapter in the understanding of the properties of materials.

7.
Angew Chem Int Ed Engl ; 59(7): 2578-2605, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31034134

RESUMEN

The accelerating development of technologies requires a significant energy consumption, and consequently the demand for advanced energy storage devices is increasing at a high rate. In the last two decades, lithium-ion batteries have been the most robust technology, supplying high energy and power density. Improving cathode materials is one of the ways to satisfy the need for even better batteries. Therefore developing new types of positive electrode materials by increasing cell voltage and capacity with stability is the best way towards the next-generation Li rechargeable batteries. To achieve this goal, understanding the principles of the materials and recognizing the problems confronting the state-of-the-art cathode materials are essential prerequisites. This Review presents various high-energy cathode materials which can be used to build next-generation lithium-ion batteries. It includes nickel and lithium-rich layered oxide materials, high voltage spinel oxides, polyanion, cation disordered rock-salt oxides and conversion materials. Particular emphasis is given to the general reaction and degradation mechanisms during the operation as well as the main challenges and strategies to overcome the drawbacks of these materials.

8.
Appl Microbiol Biotechnol ; 97(6): 2701-10, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22569638

RESUMEN

The feasibility of using a microalga Chlorella vulgaris YSW-04 was investigated for removal of nutrients from piggery wastewater effluent. The consequent lipid production by the microalga was also identified and quantitatively determined. The wastewater effluent was diluted to different concentrations ranging from 20 to 80 % of the original using either synthetic media or distilled water. The dilution effect on both lipid production and nutrient removal was evaluated, and growth rate of C. vulgaris was also monitored. Dilution of the wastewater effluent improved microalgal growth, lipid productivity, and nutrient removal. The growth rate of C. vulgaris was increased with decreased concentration of piggery wastewater in the culture media regardless of the diluent type. Lipid production was relatively higher when using synthetic media than using distilled water for dilution of wastewater. The composition of fatty acids accumulated in microalgal biomass was dependent upon both dilution ratio and diluent type. The microalga grown on a 20 % concentration of wastewater effluent diluted with distilled water was more promising for generating high-efficient biodiesel compared to the other culture conditions. The highest removal of inorganic nutrients was also achieved at the same dilution condition. Our results revealed the optimal pretreatment condition for the biodegradation of piggery wastewater with microalgae for subsequent production of high-efficient biodiesel.


Asunto(s)
Chlorella vulgaris/crecimiento & desarrollo , Chlorella vulgaris/metabolismo , Metabolismo de los Lípidos , Aguas Residuales/microbiología , Animales , Biocombustibles , Compuestos Inorgánicos/metabolismo , Porcinos , Eliminación de Residuos Líquidos
9.
Environ Technol ; 34(1-4): 495-502, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23530364

RESUMEN

Chlortetracycline (CTC) is a hazardous material in aquatic environments. This study was focused on optimization of photocatalytic ozonation processes for removal of CTC from wastewater at pH 2.2 and 7.0. In this study, the tested processes for CTC removal were arranged from the least efficient to the most efficient as: UV, UV/TiO2, O3, O3/UV and O3/UV/TiO2. Ozonation efficiency was due to ozone affinity for electron-rich sites on the CTC molecule. In the O3/UV and O3/UV/TiO2 processes, efficiency was increased by the photolysis of CTC and generation of *OH. At pH 7.0, all the processes were more efficient for CTC degradation than at pH 2.2 due to CTC speciation, ozone decay to *OH and the attractions between ionized CTC and TiO2 particles. UV/O3 at pH 7.0 showed an additive effect while other combination processes showed a synergistic effect that resulted in higher rates of reactions than the sums of individual reaction rates. The TOC removal ranged from 8% to 41% after one hour of reaction, with the above-mentioned order of efficiency. The biodegradability increased rapidly during the early minutes of the reaction. A reaction time of 10-15 min was sufficient for near maximum biodegradability, making these processes good pretreatments for the biological processes.


Asunto(s)
Clortetraciclina/química , Ozono/química , Fotólisis , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Análisis de la Demanda Biológica de Oxígeno , Clortetraciclina/efectos de la radiación , Titanio/química , Rayos Ultravioleta , Contaminantes Químicos del Agua/efectos de la radiación
10.
Chemosphere ; 345: 140422, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37844706

RESUMEN

Calcium (Ca2+) and magnesium (Mg2+) are the major scaling ions of reverse osmosis concentrate in zero-liquid discharge systems, causing performance decline. In this study, we predicted the removal of Ca2+ and Mg2+ from simulated reverse osmosis concentrate by functional polyketones (FPKs). Four amines, including 1,2-diaminopropane (DAP), 1-(2-aminoethyl) piperazine (AEP), 1-(3-aminopropyl) imidazole (API), and butyl amine (BA) used to synthesize FPKs. The effects of various factors such as the amount of adsorbent, feed water concentration, and pH were investigated for process optimization. In this study, ensemble learner artificial intelligence models, decision tree (DT), extreme gradient boost (XGB), and random forest (RF) were used to predict Ca2+ and Mg2+ removal by the FPKs. Datasets were collected experimentally using FPKs to remove Ca2+ and Mg2+ from the simulated reverse osmosis concentrate. The predictions were made by XGB, DT, and RF models for the first chosen amine for Ca2+ and then for Mg2+, subsequently, this process was repeated with each amine. The developed DT, RF, and XGB models demonstrated higher coefficients of determination for predicting Mg2+ removal by AEP and DAP (R2 = 0.841-0.935) than by API and BA (R2 = 0.774-0.801) except in the RF and XGB model results (R2 = 0.801-0.846). Overall, the XGB model displayed good results for both Ca2+ and Mg2+ removal but slight changes were observed in the AEP and BA predictions by DT and RF. Therefore, artificial intelligence models may be a viable alternative for further insight in predicting Ca2+ and Mg2+ removal by FPKs from simulated reverse osmosis concentrate.


Asunto(s)
Calcio , Purificación del Agua , Magnesio , Inteligencia Artificial , Ósmosis , Purificación del Agua/métodos , Calcio de la Dieta , Aminas
11.
Chemosphere ; 313: 137336, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36427574

RESUMEN

Heated aluminum oxide particles impregnated with Prussian blue (HAOPs-PB) are synthesized for the first time using different molar ratios of aluminum sulfate and PB to improve the adsorption of cesium (133Cs+) and natural organic matter (NOM) from an aqueous solution. The Cs+ adsorption from various aqueous solutions, including surface, tap and deionized water by synthesized HAOPs-PB, is investigated. The influencing factors such as HAOPs-PB mixing ratio, pH and dosage are studied. In addition, pseudo 1st and 2nd order is tested for adsorption kinetics study. A machine learning model is developed using gene expression programming (GEP) to evaluate and optimize the adsorption process for Cs+ and NOM removal. Synthesized adsorbent showed maximum adsorption at a 1:1 M ratio of aluminum sulfate and PB in DI, tap, and surface water. The pseudo 2nd order kinetics model described the Cs + adsorption by HAOPs-PB more accurately that indicating physiochemical adsorption. Adsorption of Cs+ showed an increasing trend with higher HAOPs-PB concentration, while high pH also favored the adsorption. Maximum NOM adsorption is found at a higher HAOPs-PB dosage and a neutral pH value. Furthermore, the proposed GEP model shows outstanding performance for Cs+ adsorption modeling, whereas a modified-GEP model presents promising results for NOM adsorption prediction for testing dataset by learning the relationship between inputs and output with R2 values of 0.9348 and 0.889, respectively.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Óxido de Aluminio , Adsorción , Purificación del Agua/métodos , Cesio , Agua , Cinética , Concentración de Iones de Hidrógeno
12.
Mater Horiz ; 10(3): 829-841, 2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36597945

RESUMEN

Although Li- and Mn-rich layered oxides are attractive cathode materials possessing high energy densities, they have not been commercialized owing to voltage decay, low rate capability, poor capacity retention, and high irreversible capacity in the first cycle. To circumvent these issues, we propose a Li1.2Ni0.13Co0.13Mn0.53Nb0.01O2 (Nb-LNCM) cathode material, wherein Nb doping strengthens the transition metal oxide (TM-O) bond and alleviates the anisotropic lattice distortion while stabilizing the layered structure. During long-term cycling, maintaining a wider LiO6 interslab thickness in Nb-LNCM creates a favorable Li+ diffusion path, which improves the rate capability. Moreover, Nb doping can decrease oxygen loss, suppress the phase transition from layered to spinel and rock-salt structures, and relieve structural degradation. Nb doping results in less capacity contributions of Mn and Co and more reversible Ni and O redox reactions compared to pristine Li1.2Ni0.133Co0.133Mn0.533O2 (LNCM), which significantly mitigates the voltage decay (Δ0.289 and Δ0.516 V for Nb-LNCM and LNCM, respectively) and ensures stable capacity retention (82.7 and 70.3% for Nb-LNCM and LNCM, respectively) during the initial 100 cycles. Our study demonstrates that Nb doping is an effective and practical strategy to enhance the structural and electrochemical integrity of Li- and Mn-rich layered oxides. This promotes the development of stable cathode materials for high-energy-density lithium-ion batteries.

13.
Biomaterials ; 296: 122073, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36905756

RESUMEN

Measuring internal mechanical stresses within 3D tissues can provide important insights into drivers of morphogenesis and disease progression. Cell-sized hydrogel microspheres have recently emerged as a powerful technique to probe tissue mechanobiology, as they can be sufficiently soft as to deform within remodelling tissues, and optically imaged to measure internal stresses. However, measuring stresses at resolutions of ∼10 Pa requires ultrasoft, low-polymer content hydrogel formulations that are challenging to label with sufficiently fluorescent materials to support repeated measurements, particularly in optically dense tissues over 100 µm thick, as required in cancer tumor models. Here, we leverage thermodynamic partitioning of hydrogel components to create "edge-labelled" ultrasoft hydrogel microdroplets, in a single polymerization step. Bright and stable fluorescent nanoparticles preferentially polymerize at the hydrogel droplet interface, and can be used to repeatedly track sensor surfaces over long-term experiments, even when embedded deep in light-scattering tissues. We utilize these edge-labelled microspherical stress gauges (eMSGs) in inducible breast cancer tumor models of invasion, and demonstrate distinctive internal stress patterns that arise from cell-matrix interactions at different stages of breast cancer progression. Our studies demonstrate a long-term macroscale compaction of the tumor during matrix encapsulation, but only a short-term increase in local stress as non-invasive tumors rapidly make small internal reorganizations that reduce the mechanical stress to baseline levels. In contrast, once invasion programs are initiated, internal stress throughout the tumor is negligible. These findings suggest that internal tumor stresses may initially prime the cells to invade, but are lost once invasion occurs. Together, this work demonstrates that mapping internal mechanical stress in tumors may have utility in advancing cancer prognostic strategies, and that eMSGs can have broad utility in understanding dynamic mechanical processes of disease and development.


Asunto(s)
Neoplasias de la Mama , Hidrogeles , Humanos , Femenino , Fenómenos Mecánicos , Neoplasias de la Mama/patología , Estrés Mecánico
14.
Artículo en Inglés | MEDLINE | ID: mdl-36673942

RESUMEN

It is known that occupational exposure to specific agents is associated with leukemia. However, whether the occupational risks of leukemia differ among various industrial groups remains unclear. Therefore, the purpose of this study was to elucidate the occupational risks of leukemia among different worker groups by industry. Data for a total of 11,050,398 people from the National Health Insurance System's claim data from 2007 to 2015 were analyzed. By cohort inclusion of workers whose industry had not changed for three years and with total workers as a control group, the risk for a specific industry group was expressed as an age-standardized incidence ratio (SIR). Among groups by industry, 'Manufacture of motor vehicles and engines for motor vehicles', 'Sale of motor vehicle parts and accessories', and 'Personal care services' showed significantly higher SIRs. In division analysis, the 'Manufacture of other machinery and equipment' and 'Waste collection, treatment and disposal activities' divisions showed significantly higher SIRs than other divisions. We identified an increased risk of leukemia in workers of certain industries in Korea. Based on the results of this study, it is necessary to create a policy to protect workers at risk of leukemia. Various additional studies are needed to protect workers by revealing more precise relationships between individual hazardous substances, processes, and leukemia.


Asunto(s)
Leucemia , Enfermedades Profesionales , Exposición Profesional , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Leucemia/epidemiología , Leucemia/complicaciones , Exposición Profesional/efectos adversos , Incidencia , República de Corea/epidemiología
15.
Epidemiol Health ; 45: e2023042, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37054725

RESUMEN

OBJECTIVES: In recent years, occupational injuries have sparked a huge social and political debate. Thus, in this study, we focused on the characteristics and trends of occupational injuries requiring hospitalization in Korea. METHODS: The Korea National Hospital Discharge In-depth Injury Survey was designed to estimate the annual number and characteristics of all injury-related hospitalizations in Korea. The annual number of hospitalizations due to occupational injuries and the age-standardized rates (ASRs) were estimated from 2006 to 2019. The annual percentage change (APC) and average annual percentage change (AAPC) of ASRs and their 95% confidence intervals (CIs) were calculated using joinpoint regression. All analyses were stratified by gender. RESULTS: In men, the APC of the ASRs of all-cause occupational injuries was -3.1% (95% CI, -4.5 to -1.7) in 2006-2015. However, a non-significant upward trend was observed after 2015 (APC, 3.3%; 95% CI, -1.6 to 8.5). In women, the APC of all-cause occupational injuries was -8.6% (95% CI, -12.1 to -5.1) in 2006-2012. However, a non-significant upward trend was observed after 2012 (APC, 2.1%; 95% CI, -0.9 to 5.2). A recent upward trend in stabbing injuries was observed after 2012 (APC, 4.7%; 95% CI, -1.8 to 11.8) in women. A non-significant overall increasing trend was also observed for occupational injuries caused by exposure to extreme temperatures (AAPC, 3.7%; 95% CI, -1.1 to 8.7) in women. CONCLUSIONS: A recent upward trend in all-cause injury hospitalizations and hospitalizations caused by stabbing injuries was observed. Therefore, active policy interventions are required to prevent occupational injuries.


Asunto(s)
Hospitalización , Traumatismos Ocupacionales , Femenino , Humanos , Masculino , Hospitalización/tendencias , Hospitales , Traumatismos Ocupacionales/epidemiología , Alta del Paciente , República de Corea/epidemiología
16.
J Epidemiol Community Health ; 77(6): 355-361, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37028925

RESUMEN

BACKGROUND: We investigated associations for long working hours in relation to physical inactivity and high-level physical activity among middle-aged and older adults. METHODS: Our study included 5402 participants and 21 595 observations from the Korean Longitudinal Study of Ageing (2006-2020). Logistic mixed models were used to estimate ORs and 95% CIs. Physical inactivity was defined as not engaging in any type of physical activity, while high-level physical activity was defined as engaging in ≥150 min per week of physical activity. RESULTS: Working >40 hours weekly was positively related to physical inactivity (OR (95% CI) 1.48 (1.35 to 1.61)) and negatively related to high-level physical activity (0.72 (95% CI 0.65 to 0.79)). Exposure to long working hours consecutively for ≥3 waves was associated with the highest OR for physical inactivity (1.62 (95% CI 1.42 to 1.85)) and the lowest OR for high-level physical activity (0.71 (95% CI 0.62 to 0.82)). Furthermore, compared with persistent short working hours (≤40 hours → ≤40 hours), long working hours in a previous wave (>40 hours → ≤40 hours) were associated with a higher OR of physical inactivity (1.28 (95% CI 1.11 to 1.49)). Exposure to an increase in working hours (≤40 hours → >40 hours) was also associated with a higher OR of physical inactivity (1.53 (95% CI 1.29 to 1.82)). CONCLUSION: We found that having working long hours was associated with a higher risk of physical inactivity and a lower likelihood of high-level physical activity. Moreover, accumulation of long working hours was associated with a higher risk of physical inactivity.


Asunto(s)
Ejercicio Físico , Conducta Sedentaria , Persona de Mediana Edad , Humanos , Anciano , Estudios Longitudinales , Envejecimiento , República de Corea/epidemiología
17.
Artículo en Inglés | MEDLINE | ID: mdl-36901074

RESUMEN

The adoption rate of performance-based pay systems has increased in recent years, and the adverse effects of systems have been emphasized. However, no study has analyzed the increase in the risk of depression/anxiety symptoms caused by the pay system in Korea. This study aimed to reveal the association between performance-based pay systems and symptoms of depression/anxiety, using data from the fifth Korean Working Conditions Survey. Depressive/anxiety symptoms were assessed using "yes" or "no" questions regarding medical problems related to depression/anxiety. The performance-based pay system and job stress were estimated using self-response answers. Logistic regression analyses were conducted to determine the association between performance-based pay systems, job stress, and symptoms of depression/anxiety using data from 27,793 participants. The performance-based pay system significantly increased the risk of the symptoms. Additionally, risk increments were calculated after grouping by pay system and job stress. Workers with two risk factors had the highest risk of symptoms of depression/anxiety for both sexes (male: OR 3.05; 95% CI 1.70-5.45; female: OR 2.15; 95% CI 1.32-3.50), implying synergistic effect of performance-based pay system and job stress on depression/anxiety symptoms. Based on these findings, policies should be established for early detection and protection against the risk of depression/anxiety.


Asunto(s)
Depresión , Estrés Laboral , Humanos , Masculino , Femenino , Condiciones de Trabajo , Ansiedad , República de Corea
18.
Addiction ; 118(11): 2118-2127, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37465920

RESUMEN

BACKGROUND AND AIMS: Previous studies have found that job satisfaction is closely associated with various health outcomes of workers. Our study measured the association between job satisfaction and current smoking and change in smoking behavior. DESIGN: Data from the longitudinal Korea Labor and Income Panel Study (KLIPS) that consist of nationally representative samples were used. The repeated measures analysis was conducted. SETTING: South Korea, 2005-2021. PARTICIPANTS: In total, 21 154 workers in Korea followed from 2005 to 2021 (145 120 observations) were included as study participants. MEASUREMENTS: The main predictor variable, job satisfaction, was assessed using a five-item general job satisfaction questionnaire. Job satisfaction was classified into 'dissatisfied', 'neutral' and 'satisfied', according to the tertiles of the sum of scores. The outcomes of interest were current smoking and initiation and cessation of smoking in the subsequent year. FINDINGS: Compared with those with a neutral level of job satisfaction, those who reported dissatisfaction with their job had an increased risk of smoking initiation [odds ratio (OR) = 1.11, 95% confidence interval (CI) = 1.01-1.22)]. Workers satisfied with their jobs were associated with a decreased likelihood of current smoking (OR = 0.96, 95% CI = 0.94-0.98) and smoking initiation (OR = 0.90, 95% CI = 0.81-0.99). There was a positive relationship between cumulative years of job dissatisfaction and smoking risk: > 4 years of experiencing job dissatisfaction was positively related to current smoking (OR = 1.14, 95% CI = 1.06-1.24) and smoking initiation (OR = 1.22, 95% CI = 1.00-1.49) and negatively related to smoking cessation (OR = 0.84, 95% CI = 0.72-0.99). CONCLUSIONS: In Korea, job dissatisfaction appears to be associated with an increased risk of smoking initiation.


Asunto(s)
Satisfacción en el Trabajo , Cese del Hábito de Fumar , Humanos , Estudios Longitudinales , Fumar Tabaco , Encuestas y Cuestionarios , República de Corea/epidemiología
19.
Sci Total Environ ; 844: 157081, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-35780878

RESUMEN

Currently, reverse osmosis concentrate (ROC) treatment is one of the most promising techniques for its disposal because it produces freshwater with high recovery and valuable materials such as salts and reduces waste volume and environmental pollution. Public attention to the severe consequences of water pollution and strict environmental regulations on wastewater discharge has pushed water-polluting industries toward zero-liquid discharge (ZLD). However, scaling and fouling problems increase energy consumption and limit permeate flux at high salt concentrations, mainly due to calcium, magnesium, and silica precipitation, ultimately decreasing ZLD performance. Therefore, this study discusses drivers and ROC pretreatment technologies to improve ZLD efficiency and presents a scientometric review of global trends. The advantages, disadvantages, and economic and environmental aspects of conventional and emerging pre-treatment technologies were studied. Traditional treatment of chemical processes combined with precipitation removes a large amount of scaling ions; however, high operation and maintenance costs and limited full-scale plant experience are the main drawbacks. Softening and coagulation are most commonly applied to treat large volumes at a moderate cost; however, substantial sludge production and increased conductivity are major operational issues. Moreover, emerging technologies efficiently remove scale-forming ions with high capital and operating costs. New variations in standard reverse osmosis technologies have improved ZLD efficiency; nonetheless, scaling and fouling are of concern. Therefore, this review presents the studies on ROC pre-treatment technologies for removing scaling ions to enhance ZLD efficiency, which can help in future research.


Asunto(s)
Purificación del Agua , Filtración/métodos , Iones , Membranas Artificiales , Ósmosis , Aguas Residuales , Purificación del Agua/métodos
20.
Artículo en Inglés | MEDLINE | ID: mdl-35409846

RESUMEN

Changes in the regularity of working hours affect the cognitive function of middle-aged workers. This study investigated the association between alterations in the regularity of working hours and cognitive impairment in middle-aged and elderly Korean workers. The data from the Korean Longitudinal Study of Aging were analyzed and cognitive function was evaluated using the Korean version of the mini−mental state examination. A score of <23 points was defined as cognitive impairment. The effect of changes in the regularity of working hours on cognitive impairment development was assessed using the generalized estimating equation model. Compared with regular working hours group, the odds ratios (ORs; 95% confidence interval) of the "consistently irregular", "regular to irregular", and "irregular to regular" groups were 1.56 (1.30−1.88), 1.46 (1.20−1.77), and 1.24 (1.01−1.53), respectively. The risk of cognitive deterioration was found in the "consistently irregular" group. However, only workers with normal working hours in the "regular to irregular" group had a significant risk of cognitive deterioration (1.51 (1.21−1.89)). Altered working hours were associated with cognitive impairment in middle-aged and older workers. The study emphasizes the need to implement a standard work schedule that is suitable for middle-aged workers.


Asunto(s)
Disfunción Cognitiva , Anciano , Envejecimiento , Cognición , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Humanos , Estudios Longitudinales , Persona de Mediana Edad , República de Corea/epidemiología
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