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1.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35197286

RESUMEN

Redox flow batteries (RFBs) are attractive large-scale energy storage techniques, achieving remarkable progress in performance enhancement for the last decades. Nevertheless, an in-depth understanding of the reaction mechanism still remains challenging due to its unique operation mechanism, where electrochemistry and hydrodynamics simultaneously govern battery performance. Thus, to elucidate the precise reactions occurring in RFB systems, an appropriate analysis technique that enables the real-time observation of electrokinetic phenomena is indispensable. Herein, we report in operando visualization and analytical study of RFBs by employing a membrane-free microfluidic platform, that is, a membrane-free microfluidic RFB. Using this platform, the electrokinetic investigations were carried out for the 5,10-bis(2-methoxyethyl)-5,10-dihydrophenazine (BMEPZ) catholyte, which has been recently proposed as a high-performance multiredox organic molecule. Taking advantage of the inherent colorimetric property of BMEPZ, we unravel the intrinsic electrochemical properties in terms of charge and mass transfer kinetics during the multiredox reaction through in operando visualization, which enables theoretical study of physicochemical hydrodynamics in electrochemical systems. Based on insights on the electrokinetic limitations in RFBs, we verify the validity of electrode geometry design that can suppress the range of the depletion region, leading to enhanced cell performance.

2.
Environ Res ; 183: 109162, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32018206

RESUMEN

Meat-grilling restaurants are considered to be residential emission sources of air pollutants. To investigate the emission characteristics of particulate matter (PM), odors, and volatile organic compounds (VOCs) from the grilling of meat, a grilling apparatus equipped with butane gas burners was used to grill pork belly and marinated pork ribs in a laboratory setting. When grilling the pork belly, the emission factor for PM with a diameter of 2.5 µm or below (PM2.5) was 754 mg-PM·kg-meat-1, accounting for 99% of total suspended particles (TSPs), while that of the marinated pork ribs was 137 mg-PM·kg-meat-1 (96% of TSPs). Ammonia and acetaldehyde were the most common odors emitted during grilling at 43-88 mg·kg-meat-1 and 22-30 mg·kg-meat-1, respectively. Aldehydes were the most significant contributor to total odor intensity (36%-67%). Benzene, vinyl acetate, and hexene were the most abundant VOCs for the pork belly, while butane, vinyl acetate, and n-dodecane were the most abundant for the marinated ribs. Among the VOCs emitted from the pork grilling process, hexene, butane, and toluene were the dominant ozone precursors. The information obtained in this study is useful for furthering the understanding of the characteristics of air pollutants emitted from actual meat-grilling restaurants. Additionally, knowledge of the PM, odor, and VOC emission characteristics and their emission factors is useful for establishing management strategies for air pollutants from meat-grilling restaurants.


Asunto(s)
Contaminantes Atmosféricos , Carne Roja , Compuestos Orgánicos Volátiles , Animales , Monitoreo del Ambiente , Odorantes , Material Particulado , Porcinos
3.
Artículo en Inglés | MEDLINE | ID: mdl-31656118

RESUMEN

Effects of operational parameters (initial nitrite concentration, initial nitrate concentration, carbon source, and COD/N ratio) on denitrification performance was evaluated using a sequencing batch reactor (SBR) under intermittent aeration. Complete denitrification was observed without N2O accumulation when the initial nitrite concentration was 100-500 mg-N·L-1. When the initial nitrate concentration was 75-300 mg-N·L-1, 95-96% of NO3--N was completely reduced to N2 gas. Acetate was the most effective sole carbon source for the complete denitrification of the SBR under intermittent aeration, and 99% of NO3--N was reduced to N2 gas. The optimum COD/N ratio was 8-12 for the complete denitrification, while NO2- accumulation was observed at low COD/N ratios of 1 and 2. In this study, N2O accumulation was not observed during the denitrification process regardless of operational condition. Paracoccus (15-68%), a representative aerobic denitrifying bacterium, was dominant in the SBR during the denitrification process, and the intermittent aeration condition could affect the abundance of Paracoccus in this study.


Asunto(s)
Reactores Biológicos/microbiología , Desnitrificación , Paracoccus/crecimiento & desarrollo , Purificación del Agua/métodos , Aerobiosis , Análisis de la Demanda Biológica de Oxígeno , Carbono/análisis , Nitratos/análisis , Nitritos/análisis , Nitrógeno/análisis
4.
Artículo en Inglés | MEDLINE | ID: mdl-32960129

RESUMEN

A new nitrous oxide (N2O)-reducing bacterium was isolated from a consortium that was enriched using advanced wastewater treatment sludge as an inoculum and N2O as the sole nitrogen source. The isolated facultative anaerobe was identified as Azospira sp. HJ23. Azospira sp. HJ23 exhibited optimum N2O-reducing activity with a C/N ratio of 62 at pH 6 in the temperature range of 37 °C to 40 °C. The optimum carbon source for N2O reduction was a mixture of glucose and acetate. The maximum rate of N2O reduction by Azospira sp. HJ23 was 4.8 mmol·g-dry cell-1·h-1, and its N2O-reducing activity was higher than other known N2O reducers. Azospira sp. HJ23 possessed several functional genes for denitrification. These included narG (NO3- reductase), nirK (NO2- reductase), norB (NO reductase), and nosZ (N2O reductase) genes. These results suggest that Azospira sp. HJ23 can be applied in the denitrification process to minimalize N2O emission.


Asunto(s)
Óxido Nitroso/análisis , Rhodocyclaceae/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Desnitrificación , Genes Bacterianos , Consorcios Microbianos/genética , Filogenia , Rhodocyclaceae/genética , Rhodocyclaceae/crecimiento & desarrollo , Aguas Residuales/química
5.
Artículo en Inglés | MEDLINE | ID: mdl-32475209

RESUMEN

Grilling restaurants are a major contributor to airborne particulate matter (PM) in metropolitan areas. In this study, the removal of PM during the grilling of pork belly using an orifice scrubber, which is a form of gas-induced spray scrubber, was assessed. During grilling, the particle mass concentration was the highest for 1.0 < PM ≤ 2.5 µm (55.5% of total PM emissions), followed by 0.5 < PM ≤ 1.0 (27.1%), PM ≤ 0.5 (10.7%), and PM > 2.5 µm (7.0%). The PM removal efficiency of the orifice scrubber at a gas flow of 4.5 m3 min-1 was > 99.7% for PM ≥ 2.5 µm, 89.4% for 1.0 < PM ≤ 2.5 µm, 62.1% for 0.5 < PM ≤ 1.0, and 36.5% for PM ≤ 0.5 µm. Although further research is necessary to optimize its use, the orifice scrubber offers a user-friendly technology for the control of PM in small grilling restaurants because of its simple design, uncomplicated operation, and satisfactory PM removal performance.


Asunto(s)
Contaminantes Atmosféricos/aislamiento & purificación , Contaminación del Aire/prevención & control , Material Particulado/aislamiento & purificación , Restaurantes , Administración de Residuos/instrumentación , Animales , Culinaria , Tamaño de la Partícula , Carne Roja , República de Corea , Porcinos
6.
J Clin Med ; 13(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38930122

RESUMEN

Background/Objectives: Preoperative fasting guidelines traditionally aim to reduce pulmonary aspiration risk. However, concerns over the adverse effects of prolonged fasting have led to exploring alternatives. This study aimed to investigate the impact of preoperative clear liquid intake on postoperative outcomes in children undergoing minimally invasive repair of pectus excavatum (MIRPE). Methods: A prospective randomized controlled study was conducted on children aged 3-6 years scheduled for elective MIRPE. Patients were randomized into either a routine overnight fasting group (NPO) or a clear liquid group. The incidence and severity of emergence delirium (ED) were assessed using Pediatric Anesthesia Emergence Delirium (PAED) and Watcha scales at recovery room. Postoperative pain scores and opioid requirements were evaluated at intervals of 1-6 h, 6-12 h, and 12-24 h after surgery. Results: Fasting time was 178.6 ± 149.5 min and 608.9 ± 148.4 min in the clear liquid group compared and NPO group, respectively. The incidence of ED, measured by PAED and Watcha scales, was lower in the clear liquid group (PAED score ≥ 12: 55.6% vs. 85.2%, p = 0.037; Watcha score ≥ 3: 51.9% vs. 85.2%, p = 0.019). The highest PAED score recorded in the recovery room was significantly lower in the clear liquid group (11.4 ± 2.8 vs. 14.6 ± 2.8, p < 0.001). Clear liquid group showed significantly lower pain scores at 1-6, 6-12, and 12-24 h postoperatively. Additionally, clear liquid group had lower opioid requirement at 1-6 and 6-12 h postoperatively. Conclusions: Preoperative clear liquid consumption was associated with a lower incidence of ED in pediatric patients undergoing MIRPE.

7.
Photoacoustics ; 33: 100561, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38021290

RESUMEN

Phase aberration caused by the skull is a major barrier to achieving high quality photoacoustic images of human and non-human primates' brains. To address this issue, time-reversal methods have been used but they are computationally demanding and slow due to relying on solving the full-wave equation. The proposed approach is based on model-based image reconstruction in the frequency-domain to achieve near real-time image reconstruction. The relationship between an imaging region and transducer array elements can be mathematically described as a model matrix and the image reconstruction can be performed by pseudo-inverse of the model matrix. The model matrix is numerically calculated due to the lack of analytical solutions for transcranial ultrasound. However, this calculation only needs to be performed once for a given experimental setup and the same acoustic medium, and is an offline process not affecting the actual image reconstruction time. This non-iterative mode-based method demonstrates a substantial improvement in image reconstruction time, being approximately 18 times faster than the time-reversal method, all while maintaining comparable image quality.

8.
J Prev Med Public Health ; 56(1): 88-94, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36746426

RESUMEN

OBJECTIVES: This study examined how deprivation differed by region and the effect those differences had on suicidal ideation among the local population. METHODS: Data collected over 10 years (2012-2021) in the Korea Welfare Panel Study were organized into 3 categories: metropolitan, city, and rural. A panel analysis was conducted on the impact of deprivation indices, socio-demographic characteristics, and life satisfaction on suicidal ideation in each category. RESULTS: Income, divorce status, family relationship satisfaction, and medical deprivation had a significant impact on suicidal ideation in metropolitan areas, whereas these variables did not have significant effects in rural areas. In other words, income, family, and medical support were more impactful in city areas. CONCLUSIONS: Although the deprivation index was higher in rural areas than in city areas due to an aging population and reduced income levels, the mental health of rural residents was found to be generally better than that of city residents. The possibility that this is related to the strength of relationships within the respective communities should be considered in light of recent discussions on relational welfare.


Asunto(s)
Renta , Ideación Suicida , Humanos , Anciano , Salud Mental , República de Corea/epidemiología , Factores de Riesgo
9.
Disaster Med Public Health Prep ; 17: e521, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37905520

RESUMEN

OBJECTIVE: The occurrence of various forms of disasters has increased worldwide. In South Korea, community resilience is particularly emphasized, especially in response to large-scale disasters in regional and group units. This study investigated the association between community resilience and the quality of life of disaster-affected people, and identified the moderating effects of perception of government relief services. METHODS: Data from the third long-term survey on the change of life of disaster-affected people conducted in 2018 by the National Disaster Management Research Institute were used. The study selected 1046 participants ages ≥ 19 years from among the disaster-affected people. Statistical analyses were performed using Model 1 of the PROCESS Macro 4.0 in the SPSS program. RESULTS: Community resilience positively affected disaster-affected people's quality of life. The perception of government relief services significantly strengthened the association between community resilience and quality of life. CONCLUSIONS: The study highlights the importance of enhancing community resilience to improve disaster-affected people's quality of life and emphasizes the role of perception of government relief services in reinforcing this relationship. Several practical and political measures that focus on improving community resilience and perception of government relief services are suggested to enhance disaster-affected people's quality of life.


Asunto(s)
Planificación en Desastres , Desastres , Humanos , Calidad de Vida , República de Corea , Gobierno , Percepción
10.
Subst Abuse Treat Prev Policy ; 17(1): 52, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35841103

RESUMEN

BACKGROUND: In recent years, female drinking has been on the rise worldwide, and this trend can be observed in Korea as well. Accordingly, this study aimed to examine the heterogeneous longitudinal changes in drinking patterns among Korean women, while also exploring the determinants of these changes. In particular, the study identified the gender perspective-related determinants of the classified patterns of problem drinking. METHODS: Data on 4615 adult women who participated in the Korea Welfare Panel Study (KOWEPS) for 3 years (2018-2020) were analyzed longitudinally using SPSS Statistics 22.0 and M-plus 7.0. The changes in female drinking patterns were analyzed using latent class growth analysis. Subsequently, multinomial logistic regression analysis was performed to identify the predictive factors affecting the changes in drinking patterns. RESULTS: Latent class analysis yielded three classes: "low problem drinking/decreased," "moderate problem drinking/maintained," and "high problem drinking/increased." Of the participants, 80.4% were in the first class, 14.5% in the second, and 5.1% in the third. After controlling for sociodemographic and psychosocial factors, we found: i) domestic violence, work-family balance stress, and gender role perception were not statistically significant for the "moderate problem drinking/maintained" class; lower levels of depression (odds ratio; OR = .750, p < .05) and higher levels of satisfaction with social relationships (OR = 1.257, p < .05) increased the probability of belonging to the "moderate problem drinking/maintained" group compared to the low problem drinking/decreased class; ii) in the "high problem drinking/increased" class, relative to the low problem drinking/decreased class, experience of domestic violence (OR = 1.857, p < .05), work-family balance stress (OR = 1.309, p < .05), and gender role perception (OR = .705, p < .05) were significant predictors of drinking behavior. CONCLUSIONS: Problem drinking in Korean women demonstrated heterogeneous patterns of change, with gender-specific factors being the main predictors of this change. Therefore, this study developed a strategy for reducing the harmful effects of female drinking, which considers the characteristics of the changes in women's drinking patterns as well as factors from the gender perspective.


Asunto(s)
Alcoholismo , Violencia Doméstica , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/psicología , Femenino , Humanos , República de Corea/epidemiología
11.
In Vivo ; 36(1): 490-495, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34972753

RESUMEN

BACKGROUND/AIM: Recently, hyaluronic acid disc has been known to enhance the success rate of fat myringoplasty. However, hyaluronic acid disc (Epidisc) is not covered by south Korean medical insurance. To date, fat myringoplasty using middle ear packing has rarely been reported. In this study, we studied whether middle ear packing with dexamethasone soaked gelfoam and fibrin glue over the fat graft could promote the success rate of tympanic membrane perforation (TMP) closure without hyaluronic acid disc, regardless of perforation size. PATIENTS AND METHODS: Between January 2005 and July 2020, a total of 209 patients who underwent fat myringoplasty due to chronic TMP at a tertiary referral center were enrolled, and the success rate and audiologic outcomes were analyzed. RESULTS: The mean successful tympanic membrane (TM) closure rate was 88.0%. The success rate by different age groups showed no significant difference. Further, the size of perforation showed no significant difference, and the perforation site (anterior or posterior) was not significant. The preoperative mean thresholds of air conduction (AC), bone conduction (BC), and air-bone gap (ABG) were 55.71, 12.98, and 42.73 dB respectively. The postoperative mean thresholds of AC, BC, and ABG were 23.67, 12.98, and 10.69 dB, respectively. Change in preoperative and postoperative hearing showed was statistically significant. CONCLUSION: Middle ear packing by gelfoam combined with external ear canal packing using fibrin glue enabled stable adhesion between the remnant TM and the fat graft. Regardless of the size of the TMP, the success rate of the fat myringoplasty by our technique can be enhanced without use of hyaluronic acid disc.


Asunto(s)
Miringoplastia , Perforación de la Membrana Timpánica , Oído Medio , Adhesivo de Tejido de Fibrina , Humanos , Ácido Hialurónico , Estudios Retrospectivos , Resultado del Tratamiento , Membrana Timpánica , Perforación de la Membrana Timpánica/cirugía
12.
J Pediatr Orthop ; 31(8): 870-4, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22101666

RESUMEN

STUDY DESIGN: Radiologic study of scoliosis in pectus excavatum patients. OBJECTIVES: To determine the relation between pectus excavatum deformity and adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: AIS may be related to other whole body deformities, but few reports have addressed the relation between chest deformity and scoliosis. METHODS: A total of 248 patients with a diagnosis of pectus excavatum were enrolled in this study. All study patients underwent whole spine anteroposterior radiographs and chest computed tomography. Severity and type of scoliosis and chest deformity were measured using radiographs, and relations between pectus deformity and AIS were analyzed. RESULTS: Overall, 56 of the 248 study patients had scoliosis (Cobb angle > 10 degrees)--a prevalence of 22.58%. The incidence of scoliosis was significantly higher in female patients (38.46%) (P = 0.002), and Lenke type 1 predominated in pectus patients (48.2%, P < 0.0001). Mean age was greater in the scoliosis group than in the nonscoliosis group (P < 0.0001), and the asymmetry of pectus deformity was more prominent in the scoliosis group (P = 0.007). However, pectus deformity severity was similar in the 2 groups (P = 0.061). Furthermore, although the scoliosis group showed a higher proportion of female patients (P = 0.002), the severities of chest and spinal deformities were similar in the 2 groups for both sexes (P = 0.314, P = 0.227). CONCLUSIONS: Pectus excavatum and AIS were found to have a high concomitant incidence. And, the age, sex, and type of disease were significantly different in the scoliosis and pectus excavatum groups. Surgeons should consider these relationships when deciding upon treatment in patients with chest and spinal deformities.


Asunto(s)
Tórax en Embudo/complicaciones , Costillas/diagnóstico por imagen , Escoliosis/etiología , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Estudios de Seguimiento , Tórax en Embudo/diagnóstico por imagen , Tórax en Embudo/epidemiología , Humanos , Incidencia , Masculino , Estudios Retrospectivos , Costillas/anomalías , Escoliosis/diagnóstico por imagen , Escoliosis/epidemiología , Distribución por Sexo , Columna Vertebral/anomalías
13.
Artículo en Inglés | MEDLINE | ID: mdl-34444638

RESUMEN

This study aimed to explore the drinking culture in Korea by sex, age, household type, occupation, and income level to identify demographic groups with prominent drinking behaviors and factors affecting their drinking. Furthermore, we evaluated recent changes, including those due to COVID-19, in drinking behavior, using data from the Korea Welfare Panel Study from 2010 to 2020. Panel analysis was performed to reveal the effects of material deprivation, depression, and sociodemographic factors on drinking behavior. We used the AUDIT 3 scale including frequency of drinking, average amount of drinking, and frequency of excessive drinking. The two characteristics of Korean drinking are consistent with the claim of the ecological system theory that humans, as social beings, drink to facilitate social communication or promote problematic drinking when social communication is difficult. Drinking among Koreans is characterized by a pattern that alternates between social drinking and problem drinking. Our study recognizes drinking as a social problem that should be managed at social as well as national levels.


Asunto(s)
Alcoholismo , COVID-19 , Consumo de Bebidas Alcohólicas/epidemiología , Humanos , República de Corea/epidemiología , SARS-CoV-2
14.
Trans R Soc Trop Med Hyg ; 97(6): 687-91, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-16117964

RESUMEN

The aim of this study was to compare the serum cytokine profiles of Plasmodium vivax malaria patients who presented with and without hepatic dysfunction. This is a retrospective analysis of 74 consecutive cases of P. vivax malaria seen at 3 military hospitals near the Demilitarized Zone in South Korea from 1999 to 2000. All patients studied were adult active duty servicemen. On admission, the mean (+/- SEM) age of the patients who presented with (n = 36) and without hepatic dysfunction (n = 38) was 21.6 +/- 0.24 and 22.5 +/- 0.44 years, respectively (P = 0.72). On admission, there was no significant difference between the 2 patient populations in terms of mean temperature, haemoglobin level, haematocrit, total white blood cell count, platelet count, parasite index, and serum concentration of transforming growth factor-beta. Plasmodium vivax malaria patients who presented with hepatic dysfunction had significantly higher mean serum concentrations of soluble Fas ligand, interleukin (IL)-l, IL-4, IL-6, IL-10, tumor necrosis factor-alpha, and interferon-gamma than those without hepatic dysfunction, suggesting the involvement of these cytokines in the development of hepatic dysfunction. The mean serum concentration of IL-12 was significantly lower in patients with hepatic dysfunction. The mean body temperature was not significantly different between the 2 patient populations.


Asunto(s)
Citocinas/sangre , Parasitosis Hepáticas/sangre , Malaria Vivax/sangre , Personal Militar , Adulto , Humanos , Corea (Geográfico) , Malaria Vivax/complicaciones , Masculino , Estudios Retrospectivos
15.
J Thorac Oncol ; 4(5): 663-5, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19395912

RESUMEN

Primary pulmonary choriocarcinoma is an extremely rare condition that is difficult to diagnose. In this report, we describe a case of primary pulmonary choriocarcinoma that presented with a hemothorax, initially diagnosed as an ectopic pregnancy. The patient was treated successfully with surgery followed by combination chemotherapy. In rare instances such as this, choriocarcinoma can originate in sites outside the genital tract; a thorough and thoughtful evaluation will ensure an accurate diagnosis and prompt treatment.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Coriocarcinoma/diagnóstico , Hemotórax/diagnóstico , Neoplasias Pulmonares/diagnóstico , Embarazo Ectópico/diagnóstico , Adulto , Coriocarcinoma/tratamiento farmacológico , Diagnóstico Diferencial , Femenino , Hemotórax/tratamiento farmacológico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Embarazo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
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