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1.
Polymers (Basel) ; 16(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38732649

RESUMEN

Water evaporation-driven energy harvesting is an emerging mechanism for contributing to green energy production with low cost. Herein, we developed polyacrylonitrile (PAN) nanofiber-based evaporation-driven electricity generators (PEEGs) to confirm the feasibility of utilizing electrospun PAN nanofiber mats in an evaporation-driven energy harvesting system. However, PAN nanofiber mats require a support substrate to enhance its durability and stability when it is applied to an evaporation-driven energy generator, which could have additional effects on generation performance. Accordingly, various support substrates, including fiberglass, copper, stainless mesh, and fabric screen, were applied to PEEGs and examined to understand their potential impacts on electrical generation outputs. As a result, the PAN nanofiber mats were successfully converted to a hydrophilic material for an evaporation-driven generator by dip-coating them in nanocarbon black (NCB) solution. Furthermore, specific electrokinetic performance trends were investigated and the peak electricity outputs of Voc were recorded to be 150.8, 6.5, 2.4, and 215.9 mV, and Isc outputs were recorded to be 143.8, 60.5, 103.8, and 121.4 µA, from PEEGs with fiberglass, copper, stainless mesh, and fabric screen substrates, respectively. Therefore, the implications of this study would provide further perspectives on the developing evaporation-induced electricity devices based on nanofiber materials.

2.
Chemosphere ; 324: 138347, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36898442

RESUMEN

The sustainable management of dredged sediment from contaminated sites needs to consider the end-use of the treated sediment. In this regard, modifying conventional sediment treatment techniques to generate a product that is suitable for a range of terrestrial uses is necessary. In the present study, we evaluated the product quality of treated sediment as a potential plant-growth medium following the thermal treatment of marine sediment contaminated by petroleum. The contaminated sediment was subject to thermal treatment at temperatures of 300, 400, or 500 °C, and no, low, or moderate oxygen availability, and the resulting treated sediment was analyzed in terms of its bulk properties, spectroscopic properties, organic contaminants, water-soluble salts and organic matter, and the leachability and extractability of heavy metals. All operational combinations for the treatment process reduced the total petroleum hydrocarbon content of the sediment from 4922 mg kg-1 to lower than 50 mg kg-1. The thermal treatment process stabilized the heavy metals in the sediment, reducing the zinc and copper concentration by up to 58.9% and 89.6%, respectively, in the leachate from the toxicity characteristic leaching procedure. The hydrophilic organic and/or sulfate salt byproducts of the treatment were phytotoxic, but these can easily be removed by washing the sediment with water. By combining the sediment analysis results with experimental data from barley germination and early-growth tests, the end product was found to be of higher quality when higher temperatures and lower oxygen availability were employed in the treatment process. These findings demonstrate that it is possible to retain the natural organic resources of the original sediment by optimizing the thermal treatment, thus ensuring a suitably high product quality for use as a plant-growth medium.


Asunto(s)
Metales Pesados , Petróleo , Temperatura , Sedimentos Geológicos/química , Metales Pesados/análisis , Agua/análisis
3.
RSC Adv ; 13(50): 35583-35591, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38077981

RESUMEN

Tirbanibulin, an FDA-approved microtubule-targeting agent (MTA) introduced in 2020, represents a pioneering treatment for precancerous actinic keratosis. Despite its failure to gain approval as an anticancer agent due to insufficient efficacy, there remains potential value in extending its application into malignancy treatment through tirbanibulin-based derivatives. Tirbanibulin possesses a distinctive dual mechanism of action involving microtubule and Src inhibition, distinguishing it from other MTAs. In spite of its unique profile, exploration of tirbanibulin's structure-activity relationship (SAR) and the development of its derivatives are significantly limited in the current literature. This study addresses this gap by synthesizing various tirbanibulin derivatives and exploring their SAR through modifications in the core amide motif and the eastern benzylamine part. Our results underscore the critical role of the pyridinyl acetamide core structure for optimal cellular potency, with favorable tolerance observed for modifications at the para position of the benzylamine moiety. Particularly noteworthy is the analogue modified with p-fluorine benzylamine, which exhibited favorable in vivo PK profiles. These findings provide crucial insights into the potential advancement of tirbanibulin-based compounds as promising anticancer agents.

4.
Occup Environ Med ; 69(9): 658-62, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22652006

RESUMEN

OBJECTIVE: To investigate the association between serum perfluorooctanoic acid (PFOA) concentration and cardiovascular disease, as measured by homocysteine level and blood pressure in a representative sample of US adults. METHODS: A cross-sectional study of 2934 adults (≥20 years) who participated in the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey and had detectable levels of PFOA in their serum. The health effects analysed as potentially associated with PFOA exposure included homocysteine level and blood pressure. RESULTS: The geometric mean value (95% CI) of the study participants' serum PFOA concentration was 4.00 µg/l (95% CI 3.86 to 4.13). The homocysteine and systolic blood pressure were shown to increase significantly with an increase in the log-transformed serum PFOA concentration, after adjusting for potential confounding variables. Adjusted ORs comparing participants at the 80th versus the 20th percentiles were 2.62 for hypertension (95% CI 2.09 to 3.14), and a positive association was also evident in models based on quartiles or based on restricted cubic splines. CONCLUSION: These findings suggest that background exposure to PFOA may continue a risk factor for the development of cardiovascular diseases.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Caprilatos/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Fluorocarburos/efectos adversos , Sustancias Peligrosas/efectos adversos , Homocisteína/sangre , Hiperhomocisteinemia/etiología , Hipertensión/etiología , Adulto , Caprilatos/sangre , Estudios Transversales , Femenino , Fluorocarburos/sangre , Sustancias Peligrosas/sangre , Humanos , Hiperhomocisteinemia/sangre , Hipertensión/sangre , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Oportunidad Relativa , Factores de Riesgo , Estados Unidos , Adulto Joven
5.
Am J Public Health ; 100(11): 2165-7, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20339078

RESUMEN

We examined how the deregulation of South Korea's labor laws during the country's 1997 to 1998 economic crisis affected occupational safety and health. Although the economic index improved after the reforms, the total injury rate declined slowly and the incidence of occupational disease increased. The withdrawal of support for occupational safety and health is likely to have a sustained effect on public health.


Asunto(s)
Recesión Económica/estadística & datos numéricos , Enfermedades Profesionales/epidemiología , Salud Laboral/estadística & datos numéricos , Humanos , Salud Laboral/legislación & jurisprudencia , República de Corea/epidemiología , Lugar de Trabajo/legislación & jurisprudencia , Lugar de Trabajo/estadística & datos numéricos , Heridas y Lesiones/epidemiología
6.
Am J Ind Med ; 52(5): 429-37, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19212948

RESUMEN

BACKGROUND: This study used static posturography to investigate the neurotoxic effects on workers exposed to mixed organic solvents at low concentrations under the levels of the threshold limit values (TLV). METHODS: Forty-one workers from four plants exposed to mixed solvents and 90 non-exposed referents were examined. The lifetime cumulative biological exposure (CE) was estimated according to subject's occupational history and biological monitoring results. Static posturography and questionnaire were the basis of data collection. RESULTS: The mean exposure index of mixed organic solvents of four plants was 0.47 (SD: 0.33, range: 0.08-1.39). The exposed group showed a larger sway area and length under the eye open condition than did the non-exposed group. In a multiple linear regression, a significant positive association was demonstrated between postural sway area and CE. CONCLUSIONS: This study results suggest that the exposure to organic solvents under TLV levels may cause disturbance in postural stability.


Asunto(s)
Monitoreo del Ambiente , Neurotoxinas/toxicidad , Exposición Profesional/efectos adversos , Exposición Profesional/análisis , Equilibrio Postural/efectos de los fármacos , Solventes/análisis , Solventes/toxicidad , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Corea (Geográfico) , Tiempo de Internación/estadística & datos numéricos , Modelos Lineales , Masculino , Persona de Mediana Edad , Neurotoxinas/análisis , Valores Limites del Umbral
7.
Arch Plast Surg ; 45(4): 325-332, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30037192

RESUMEN

BACKGROUND: Zygomaticomaxillary complex (ZMC) fractures mostly occur in the form of tripod fractures. The surgical field is accessed using a combination of three classic approaches. However, the subciliary incision may have unfavorable aesthetic results. Herein, the authors report the advantages of the extended transconjunctival approach (ETA) combined with T-bar screw reduction in minimizing scarring and complications for the treatment of ZMC fractures. METHODS: A total of 26 patients underwent ZMC reduction through the ETA and intraoral approach. A skin incision measuring roughly 5 to 8 mm in length was placed following the lateral canthal skin crease. After releasing the inferior crus of the lateral canthal tendon for canthotomy, the medial periosteum of the lateral orbital rim was preserved for canthal reattachment. A limited subperiosteal dissection and partial relaxing incision of the orbicularis oculi were performed to expose the fracture line of the inferior orbital rim and zygomaticofrontal suture. Reduction was performed using a T-bar screw through the transconjunctival incision and an elevator through the intraoral incision. RESULTS: The aesthetic and functional results were excellent. Successful reduction was achieved and the skin incision was less than 8 mm in 20 cases (76.9%). Only six patients had an additional skin incision (less than 5 mm) to achieve reduction. No cases of ectropion, entropion, or excessive scarring were noted. CONCLUSIONS: The ETA using a T-bar screw is a useful method for maximizing aesthetic results in ZMC fractures, with the advantages of minimal scarring, faster recovery, and maintenance of pretarsal fullness.

8.
Osong Public Health Res Perspect ; 5(2): 108-14, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24955321

RESUMEN

OBJECTIVES: Exposure to aircraft noise has been shown to have adverse health effects, causing annoyance and affecting the health-related quality of life, sleep, and mental states of those exposed to it. This study aimed to determine sleep quality in participants residing near an airfield and to evaluate the relationship between the levels of aircraft noise and sleep quality. METHODS: NEIGHBORING REGIONS OF A MILITARY AIRFIELD WERE DIVIDED INTO THREE GROUPS: a high exposure group, a low exposure group, and a control group. A total of 1082 participants (aged 30-79 years) completed a comprehensive self-administered questionnaire requesting information about demographics, medical history, lifestyle, and the Pittsburgh Sleep Quality Index. RESULTS: Of the 1082 participants, 1005 qualified for this study. The prevalence of sleep disturbance was 45.5% in the control group, 71.8% in the low exposure group, and 77.1% in the high exposure group (p for trend < 0.001). After adjusting for potential confounding factors, we determined the exposure-response relationship between the degree of aircraft noise and sleep quality. Of the participants with a normal mental status, the prevalence of sleep disturbance was 2.61-fold higher in the low exposure group and 3.52-fold higher in the high exposure group than in the control group. CONCLUSION: The relationship between aircraft noise and health should be further evaluated through a large-scale follow-up study.

9.
Int J Cardiol ; 163(1): 40-5, 2013 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-23164588

RESUMEN

OBJECTIVE: Recent studies have suggested that smaller thighs are a disadvantage for health and survival, but the association of thigh circumference with atherosclerosis remains uncertain. The purpose of this study was to investigate the association between thigh circumference and peripheral arterial disease (PAD), as measured by ankle brachial index (ABI). METHODS: This study used data from the National Health and Nutrition Examination Survey (1999-2004), in which participants' ABI and thigh circumference were measured simultaneously. A total of 5716 participants (2959 men and 2757 women) were included in the final analysis. A diagnosis of PAD was determined on the basis of ABI <0.9. RESULTS: The overall prevalence of PAD in this sample was 6.6%. Thigh circumference of those with PAD was 50.1cm compared to 52.2 cm for those without PAD (p < 0.0001). After adjusting for potential covariates, the prevalence of PAD generally decreased as thigh circumference increased up to 55 cm. In the first quantile (smallest thigh circumference), men and women had as much as a 4.8-fold (95% CI, 2.28-10.29) and a 3-fold (95% CI, 1.45-6.18) increased risk of PAD, respectively. Above 55 cm, PAD was no longer related to thigh circumference. CONCLUSIONS: Small thigh circumference may be associated with PAD, as measured by ABI.


Asunto(s)
Índice Tobillo Braquial/tendencias , Distribución de la Grasa Corporal/tendencias , Encuestas Nutricionales/tendencias , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/epidemiología , Muslo/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Distribución de la Grasa Corporal/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/fisiopatología , Factores de Riesgo , Estados Unidos/epidemiología
10.
Environ Health Perspect ; 120(3): 413-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22214670

RESUMEN

BACKGROUND: Few studies have been conducted to identify risk factors for balance and vestibular dysfunction in general populations, but previous studies have reported evidence of adverse effects of lead and cadmium on balance control in high-risk groups. OBJECTIVE: We evaluated the relationship between blood lead and cadmium levels and balance and vestibular dysfunction in a general population study. METHODS: We analyzed data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) of 5,574 adults ≥ 40 years of age. Balance dysfunction was evaluated by the Romberg Test of Standing Balance on Firm and Compliant Support Surfaces, which examines the ability to stand unassisted using four test conditions to evaluate vestibular system, vision, and proprioception inputs that contribute to balance. Blood levels of lead and cadmium were measured by atomic absorption spectrometry. Associations were estimated using logistic regression models adjusted for potential confounders. Associations with time to loss of balance were estimated using adjusted Cox proportional hazard models. RESULTS: The adjusted odds ratio (OR) for balance dysfunction in association with the highest quintile (3.3-48 µg/dL) versus the lowest quintile (< 1.2 µg/dL) of lead was 1.42 [95% confidence interval (CI): 1.07, 1.89]. The corresponding OR for cadmium (0.9-7.4 µg/L vs. < 0.2 µg/L) was 1.27 (95% CI: 1.01, 1.60). The adjusted hazard ratio for time to failure for the most physiologically challenging balance test among subjects with the highest vs. lowest quintiles of blood lead was 1.24 (95% CI: 1.04, 1.48). Cadmium levels were not associated with time to failure. CONCLUSIONS: Our findings suggest that blood lead and cadmium levels may be associated with balance and vestibular dysfunction in a general sample of U.S. adults.


Asunto(s)
Cadmio/sangre , Contaminantes Ambientales/sangre , Plomo/sangre , Equilibrio Postural , Trastornos de la Sensación/epidemiología , Enfermedades Vestibulares/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Estudios Retrospectivos , Trastornos de la Sensación/inducido químicamente , Espectrofotometría Atómica , Estados Unidos/epidemiología , Enfermedades Vestibulares/inducido químicamente , Pruebas de Función Vestibular
11.
PLoS One ; 7(10): e46500, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23056323

RESUMEN

BACKGROUND: We focused on whether changes in the occupational status of older male adults can be influenced by social engagement and health status measured at the baseline. METHODS: This study used a sample of the Korean Longitudinal Study of Aging (KLoSA), and the study population was restricted to 1.531 men who were aged 55 to 80 years at the 2006 baseline survey and participated in the second survey in 2008. Social engagement and health status, measured by the number of chronic diseases, grip strength, and depressive symptoms as well as covariates (age, marital status, educational level, and household income) were based on data from the 2006 baseline survey. Occupational engagement over the first and second survey was divided into four categories: 'consistently employed' (n=892), 'employed-unemployed' (n=152), 'unemployed-employed' (n=138), and 'consistently unemployed' (n=349). RESULTS: In the multinomial model, the 'consistently employed' and 'unemployed-employed' groups had significantly higher social engagement (1.19 and 1.32 times, respectively) than the referent. The number of chronic diseases was significantly associated with four occupational changes, and the 'unemployed-employed' had the fewest chronic conditions. CONCLUSION: Our finding suggests that social engagement and health status are likely to affect opportunities to continue working or to start working for older male adults.


Asunto(s)
Envejecimiento , Estado de Salud , Ocupaciones , Conducta Social , Anciano , Anciano de 80 o más Años , Humanos , Estudios Longitudinales , Persona de Mediana Edad , República de Corea
12.
Atherosclerosis ; 218(1): 200-6, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21620405

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the association between organochlorine (OC) pesticides and the prevalence of peripheral arterial disease (PAD). METHODS AND RESULTS: This study included 2032 participants from the National Health and Nutrition Examination Survey (1999-2004), in which the ankle brachial index (ABI) and serum levels of OC pesticides (p,p'-DDE, trans-nonachlor, oxychlordane, dieldrin, and ß-HCH) were measured simultaneously. A diagnosis of PAD was determined on the basis of an ABI<0.9. The obesity status was categorized as obese group (BMI ≥ 25 kg/m(2)) or non-obese group (BMI<25 kg/m(2)). Compared with subjects without PAD, those with PAD had significantly higher lipid-standardized and wet-weight concentrations of OC pesticides. Obese subjects with PAD had significantly increased mean lipid-standardization value of p,p'-DDE (OR=1.47; 95% CI, 1.08-1.99), trans-nonachlor (OR=1.68; 95% CI, 1.10-2.56), oxychlordane (OR=1.82; 95% CI, 1.09-3.03), dieldrin (OR=2.36; 95% CI, 1.69-3.31), and sums of all five pesticides (OR=1.19; 95% CI, 1.07-1.33). For non-obese group, increases in the levels of OC pesticides and their sums did not account for increased risk ratio of PAD. CONCLUSION: OC pesticides are a potent risk factor for PAD. Additionally, obesity may modulate the association between OC pesticides and the development of PAD.


Asunto(s)
Hidrocarburos Clorados/sangre , Obesidad/sangre , Obesidad/complicaciones , Enfermedad Arterial Periférica/sangre , Plaguicidas/sangre , Adulto , Anciano , Índice Tobillo Braquial , Aterosclerosis , Femenino , Humanos , Hidrocarburos Clorados/efectos adversos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Obesidad/inducido químicamente , Oportunidad Relativa , Enfermedad Arterial Periférica/complicaciones , Plaguicidas/efectos adversos , Prevalencia , Factores de Riesgo , Estados Unidos
13.
Accid Anal Prev ; 42(4): 1118-27, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20441821

RESUMEN

This paper presents a fully Bayesian multivariate approach to before-after safety evaluation. Although empirical Bayes (EB) methods have been widely accepted as statistically defensible safety evaluation tools in observational before-after studies for more than a decade, EB has some limitations such that it requires a development and calibration of reliable safety performance functions (SPFs) and the uncertainty in the EB safety effectiveness estimates may be underestimated when a fairly large reference group is not available. This is because uncertainty (standard errors) of the estimated regression coefficients and dispersion parameter in SPFs is not reflected in the final safety effectiveness estimate of EB. Fully Bayesian (FB) methodologies in safety evaluation are emerging as the state-of-the-art methods that have a potential to overcome the limitations of EB in that uncertainty in regression parameters in the FB approach is propagated throughout the model and carries through to the final safety effectiveness estimate. Nonetheless, there have not yet been many applications of fully Bayesian methods in before-after studies. Part of reasons is the lack of documentation for a step-by-step FB implementation procedure for practitioners as well as an increased complexity in computation. As opposed to the EB methods of which steps are well-documented in the literature for practitioners, the steps for implementing before-after FB evaluations have not yet been clearly established, especially in more general settings such as a before-after study with a comparison group/comparison groups. The objectives of this paper are two-fold: (1) to develop a fully Bayesian multivariate approach jointly modeling crash counts of different types or severity levels for a before-after evaluation with a comparison group/comparison groups and (2) to establish a step-by-step procedure for implementing the FB methods for a before-after evaluation with a comparison group/comparison groups. The fully Bayesian multivariate approach introduced in this paper has additional advantages over the corresponding univariate approaches (whether classical or Bayesian) in that the multivariate approach can recover the underlying correlation structure of the multivariate crash counts and can also lead to a more precise safety effectiveness estimate by taking into account correlations among different crash severities or types for estimation of the expected number of crashes. The new method is illustrated with the multivariate crash count data obtained from expressways in Korea for 13 years to assess the safety effectiveness of decreasing the posted speed limit.


Asunto(s)
Prevención de Accidentes , Accidentes de Tránsito/prevención & control , Accidentes de Tránsito/estadística & datos numéricos , Teorema de Bayes , Evaluación de Programas y Proyectos de Salud/métodos , Conducción de Automóvil/estadística & datos numéricos , Planificación Ambiental , Humanos , Corea (Geográfico) , Análisis Multivariante , Reproducibilidad de los Resultados
15.
Korean J Orthod ; 42(5): 225-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23173114
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