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1.
Small ; : e2400828, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693068

RESUMEN

Efficient support materials are crucial for maximizing the efficacy of nanomaterials in various applications such as energy storage, drug delivery, catalysis, and environmental remediation. However, traditional supports often hinder nanomaterial performance due to their high weight ratio and limited manageability, leading to issues like tube blocking and secondary pollution. To address this, a novel grapefruit-inspired polymeric capsule (GPC) as a promising carrier platform is introduced. The millimeter-scale GPC features a hydrophilic shell and an internal hierarchical microstructure with 80% void volume, providing ample space for encapsulating diverse nanomaterials including metals, polymers, metal-organic frameworks, and silica. Through liquid-phase bottom-up methods, it is successfully loaded Fe2O3, SiO2, polyacrylic acid, and Prussian blue nanomaterials onto the GPC, achieving high mass ratio (1776, 488, 898, and 634 wt.%, respectively). The GPC shell prevents nanomaterial leakage and the influx of suspended solids, while its internal framework enhances structural stability and mass transfer rates. With long-term storage stability, high carrying capacity, and versatile applicability, the GPC significantly enhances the field applicability of nanomaterials.

2.
Small ; 19(48): e2305247, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37518852

RESUMEN

The development of efficient adsorbents for the practical recovery of precious metals from electronic waste is vital to advanced energy/environment industries. Ti3 C2 Tx MXene-based materials are promising adsorbents for aqueous environments; however, the highly defective and super hydrophilic nature of the MXene surface hinders its practical applications. Here, we report that nitrogen-doped MXene (N-MXene) nanosheet stacks, prepared via high-energy planetary ball milling under N2 purging, exhibited a long-term stable and excellent recovery capability for Au and Ag ions via the nitrogenation of defective vacancies. Notably, these microscale nanosheets could facilitate the sustainable production of Au and Ag from secondary sources, exhibiting a high recovery rate and capability (1198 mg g-1 for Au and 1528 mg g-1 for Ag), long-term stable storability (21 d), and high selectivity (Kd of 1.67 × 106 for Au and 2.07 × 107 for Ag). Furthermore, the reversible redox chemistry of N-MXene facilitated its repeated use in adsorption/desorption cycles.

3.
J Environ Manage ; 328: 116971, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36516708

RESUMEN

For the in-situ remediation of the contaminated subsurface environment, the injection of nutrients and microorganisms changes chemical and physical conditions, which control the delivery and immobilization of microorganisms. We investigated the injection strategy for effective bacterial delivery in a bioaugmentation scheme by controlling ionic strength (IS) and pore-water velocity (v). A set of bacterial transport tests was conducted using the saturated sand column to mimic the saturated subsurface environment. The effectiveness of the injection strategies was evaluated by applying solutions with different ionic strengths into the sand column with different pore-water velocities. The deposition and delivery of bacteria through the sand column were analyzed using the first-order deposition model. The deposition and delivery of bacteria injected by various strategies were numerically simulated considering the variable deposition rate. The breakthrough curves from column experiments revealed that the bacterial deposition on the sand surface was increased by an increase in the ionic strength and by a decrease in the pore-water velocities. The rates of bacterial deposition (k1) on sand could be determined as a function of ionic strength and pore-water velocity, and it was applicable to simulate the delivery of bacteria under dynamic groundwater conditions. The numerical case study considering various injection strategies showed that the nutrient concentration controlled the bacterial delivery to the target area more significantly than the injection flow rate. Injection of bacterial solution with lower nutrient concentration could be increased the deposited bacterial concentration at the target point (Stp) by 6.2-7.1 times higher. Short pulse injection with a high injection rate decreased Stp by 67-78%. The efficiency of bacterial delivery (Ed) could be increased three times higher by lowering nutrient concentration in the injection solution. The process of evaluating the efficiency of bacterial delivery could be a prominent approach to determining the injection strategy for in-situ remediation considering variable conditions of a contaminated site.


Asunto(s)
Arena , Agua , Agua/química , Concentración Osmolar , Porosidad , Dióxido de Silicio
4.
Environ Monit Assess ; 195(12): 1465, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37957404

RESUMEN

Gongji Stream flows into Lake Uiam, a potable water source for the capital region of Chuncheon, South Korea. Algal blooms often occur downstream of the Gongji stream in combination with drastic flow rate variations. Downstream water quality may also be affected by Yaksa stream. Yaksa stream joins Gongji stream before it reaches Uiam Lake, which is a drinking water source for the city. Limited data exists on the Yaksa stream water quality. Therefore, water quality parameters (pH, electrical conductivity (EC), biological oxygen demand (BOD), total nitrogen (T-N), total phosphorous (T-P), chlorophyll-a (Chl-a), total coliforms, and Escherichia coli (E. coli) concentration) were sampled from Gongji (at sites GJ1 and GJ2) and Yaksa (at sites YS1 and YS2) streams from May to September, 2022. The results revealed the overall water quality of both streams was good (BOD = 0.27-3.66 mg/L; TP = 0.003-0.074 mg/L), except on August 3. On August 3, the concentrations of BOD, TP, total coliforms, and E. coli were elevated, with the highest concentrations in samples from GJ2. The recent heavy rainfall potentially caused sewage inflows near GJ2. The correlation analysis revealed positive linear relationships in the 1-day cumulative precipitation with BOD (r = 0.503), total coliforms (r = 0.547), and TP (r = 0.814). The Yaksa stream may be an Anabaena sp. source, which contaminated samples from YS1, YS2, and GJ2, but not at GJ1 (upstream of the tributary).


Asunto(s)
Monitoreo del Ambiente , Calidad del Agua , Estaciones del Año , Escherichia coli , Clorofila A/análisis , Fósforo/análisis
5.
J Aging Soc Policy ; : 1-18, 2023 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-38007618

RESUMEN

The Korean government implemented the pilot project for community care for older adults in June 2019. This study investigated the outcomes of the pilot project among Korean older adults by linking survey data from the pilot project with data of Korean National Health Insurance Service. The final sample included 17,801 pilot project participants and 68,145 in a matched comparison group. Pilot program participants experienced an increase of 4.8 days for length of home stay and a reduction of $956 (US) per participant relative to the matched comparison group. Pilot program participants with long-term care insurance who used home care services experienced an increase of 8.9 days for length of home stay and a reduction in $1,177 (US) in total costs, along with a reduction in the admission to long-term care facilities, compared to the matched comparison group. Patients discharged from hospitals indicated an increase of 35.2 days for length of home stay and a reduction of $6,947 (US) in total costs, but a 3.53 times increase in hospital readmissions relative to the matched comparison group. The pilot project for community care resulted in increased length of home stay and reduced total costs among older adults in Korea.

6.
J Psychiatry Neurosci ; 46(1): E119-E127, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33119492

RESUMEN

BACKGROUND: Although severe dementia could protect against suicide death by decreasing a person's capacity to implement a suicide plan, patients with early dementia may have better cognition, giving them more sustained insight into their disease and better enabling them to carry out a suicide plan. This study investigated suicide risk in older adults within 1 year of receiving a diagnosis of dementia. METHODS: This study used National Health Insurance Service Senior Cohort data and included 36 541 older adults with newly diagnosed dementia (a Mini-Mental State Examination score ≤ 26 and a Clinical Dementia Rating score ≥ 1 or a Global Deterioration Scale score ≥ 3), including Alzheimer disease, vascular dementia and other/unspecified dementia, from 2004 to 2012. We selected older adults without dementia through 1:1 propensity-score matching using sex, age, comorbidities and index year, with follow-up throughout 2013. We estimated adjusted hazard ratios (AHRs) of suicide deaths within 1 year after diagnosis using a time-dependent Cox proportional hazards model. RESULTS: We verified 46 suicide deaths during the first year after a dementia diagnosis. Older adults with dementia had an increased risk of suicide death compared to those without dementia (AHR 2.57; 95% confidence interval [CI] 1.49-4.44). Older adults with Alzheimer disease (AHR 2.50; 95% CI 1.41-4.44) or other/unspecified dementia (AHR 4.32; 95% CI 2.04-9.15) had an increased risk of suicide death compared to those without dementia. Patients with dementia but without other mental disorders (AHR 1.96; 95% CI 1.02-3.77) and patients with dementia and other mental disorders (AHR 3.22; 95% CI 1.78-5.83) had an increased risk of suicide death compared to patients without dementia. Patients with dementia and schizophrenia (AHR 8.73; 95% CI 2.57-29.71), mood disorders (AHR 2.84; 95% CI 1.23-6.53) or anxiety or somatoform disorders (AHR 3.53; 95% CI 1.73-7.21), respectively, had an increased risk of suicide death compared to patients with those conditions but without dementia. LIMITATIONS: This study examined only elderly patients in South Korea, a population with a substantially higher suicide rate than the global population. Caution must be exercised when generalizing the results to populations with dissimilar backgrounds. CONCLUSION: Patients with dementia had an increased risk of suicide death within 1 year after diagnosis compared to those without dementia.


Asunto(s)
Demencia/epidemiología , Suicidio/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , Demencia/diagnóstico , Demencia Vascular/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , República de Corea/epidemiología , Estudios Retrospectivos , Riesgo , Factores de Tiempo
7.
Environ Res ; 197: 111069, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33785325

RESUMEN

This study evaluated the long-term organic removal performance and microbial community shift in simulated aquifer storage and recovery (ASR) conditions. For this purpose, anoxic soil box systems were operated at 15 °C for one year. The results showed that the assimilable organic carbon (AOC) concentration in the anoxic soil box systems was successfully decreased by 79.1%. The dissolved organic carbon (DOC) concentration increased during the initial operational periods; however, it subsequently decreased during long-term operation. Readily biodegradable organic fractions (i.e., low-molecular weight (LMW) neutrals and LMW acids) decreased along with time elapsed, whereas non-biodegradable fraction (i.e., humic substances) increased. Proteobacteria and Acidobacteriota were predominant in the anoxic box systems throughout the operational periods. Firmicutes and Bacteroidota suddenly increased during the initial operational period while Gemmatimonadota slightly increased during prolonged long-term operation. Interestingly, the microbial community structures were significantly shifted with respect to the operational periods while the effects of AOC/NO3- addition were negligible. Various bacterial species preferring low temperature or anoxic conditions were detected as predominant bacteria. Some denitrifying (i.e., Noviherbaspirillum denitrificans) and iron reducing bacteria (i.e., Geobacter spp.) appeared during the long-term operation; these bacterial communities also acted as organic degraders in the simulated ASR systems. The findings of this study suggest that the application of natural bioattenuation using indigenous soil microbial communities can be a promising option as an organic carbon management strategy in ASR systems.


Asunto(s)
Agua Subterránea , Microbiota , Carbono , Oxalobacteraceae , Suelo
8.
Br J Cancer ; 122(11): 1649-1660, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32235905

RESUMEN

BACKGROUND: Oropharyngeal cancer (OPC) exhibits diverse immunological properties; however, their implications for immunotherapy are unknown. METHODS: We analysed 37 surgically resected and nine recurrent or metastatic anti-programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1)-treated OPC tumours. OPCs were classified into immune-rich (IR), mesenchymal (MS) and xenobiotic (XB) subtypes based on RNA-sequencing data. RESULTS: All IR type tumours were human papillomavirus (HPV) positive, most XB types were HPV negative, and MS types showed mixed HPV status. The IR type showed an enriched T cell exhaustion signature with PD-1+ CD8+ T cells and type I macrophages infiltrating the tumour nest on multiplex immunohistochemistry. The MS type showed an exclusion of CD8+ T cells from the tumour nest and high MS and tumour growth factor-ß signatures. The XB type showed scant CD8+ T cell infiltration and focal CD73 expression. The IR type was associated with a favourable response signature during anti-PD-1/PD-L1 therapy and showed a high APOBEC mutation signature, whereas the MS and XB types showed resistance signature upregulation. Among anti-PD-1/PD-L1-treated OPC patients, the IR type showed a favourable clinical response (3/4 patients), whereas the XB type showed early progression (3/3 patients). CONCLUSION: Our analysis classified OPCs into three subtypes with distinct immune microenvironments that are potentially related to the response to anti-PD-1/PD-L1 therapy.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Orofaríngeas/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Microambiente Tumoral/inmunología , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias Orofaríngeas/tratamiento farmacológico , Neoplasias Orofaríngeas/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Transcriptoma
10.
Br J Cancer ; 123(12): 1720-1729, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32963347

RESUMEN

BACKGROUND: Recurrent and/or metastatic squamous cell carcinoma of head and neck (R/M SCCHN) is a common cancer with high recurrence and mortality. Current treatments have low response rates (RRs). METHODS: Fifty-three patients with R/M SCCHN received continuous oral buparlisib. In parallel, patient-derived xenografts (PDXs) were established in mice to evaluate resistance mechanisms and efficacy of buparlisib/cetuximab combination. Baseline and on-treatment tumour genomes and transcriptomes were sequenced. Based on the integrated clinical and PDX data, 11 patients with progression under buparlisib monotherapy were treated with a combination of buparlisib and cetuximab. RESULTS: For buparlisib monotherapy, disease control rate (DCR) was 49%, RR was 3% and median progression-free survival (PFS) and overall survival (OS) were 63 and 143 days, respectively. For combination therapy, DCR was 91%, RR was 18% and median PFS and OS were 111 and 206 days, respectively. Four PDX models were originated from patients enrolled in the current clinical trial. While buparlisib alone did not inhibit tumour growth, combination therapy achieved tumour inhibition in three of seven PDXs. Genes associated with apoptosis and cell-cycle arrest were expressed at higher levels with combination treatment than with buparlisib or cetuximab alone. CONCLUSIONS: The buparlisib/cetuximab combination has significant promise as a treatment strategy for R/M SCCHN. CLINICAL TRIAL REGISTRATION: NCT01527877.


Asunto(s)
Aminopiridinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cetuximab/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Morfolinas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Aminopiridinas/efectos adversos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Apoptosis/genética , Puntos de Control del Ciclo Celular/genética , Supervivencia Celular/efectos de los fármacos , Cetuximab/efectos adversos , Variaciones en el Número de Copia de ADN , Resistencia a Antineoplásicos , Femenino , Perfilación de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Ratones , Ratones Desnudos , Ratones SCID , Persona de Mediana Edad , Morfolinas/efectos adversos , Mutación , Trasplante de Neoplasias , Supervivencia sin Progresión , Reproducibilidad de los Resultados , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Resultado del Tratamiento , Regulación hacia Arriba/genética , Secuenciación Completa del Genoma/métodos
11.
Cardiovasc Diabetol ; 19(1): 61, 2020 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-32404104

RESUMEN

BACKGROUND: Sleep disturbance has been significantly associated with the incidence of cardiovascular disease (CVD) in the general population. However, despite the common prevalence of sleep disturbance in patients with type 2 diabetes, its relationship with the risk of CVD remains unclear. Here, we have examined the association of sleep disturbance with the incidence of all CVD and all-cause mortality in patients with newly-diagnosed type 2 diabetes. METHODS: We used the Korean National Health Insurance Service-Health Screening Cohort data and included 36,058 patients with new-onset type 2 diabetes aged ≥ 40 years between 2004 and 2007, along with follow-up examinations to 2013. We used the ICD-10 code to measure sleep disturbance as a primary diagnosis and the multivariable Cox proportional hazards regression models to estimate the adjusted hazard ratio (AHR) and 95% confidence interval (CI) of all CVD, coronary heart disease (CHD), stroke, and all-cause mortality. RESULTS: We identified 6897 cases of all CVD (CHD, n = 4138; stroke, n = 2759) and 2890 events of all-cause mortality during a mean follow-up period of 7.0 years. Sleep disturbance was associated with an increased risk of All CVD (AHR, 1.24; 95% CI, 1.06-1.46), CHD events (AHR, 1.24; 95% CI, 1.00-1.53), and all-cause mortality (AHR, 1.47; 95% CI, 1.15-1.87) in patients with new-onset type 2 diabetes. Furthermore, women (AHR, 1.33; 95% CI, 1.06-1.67) and middle-aged adults (AHR, 1.29; 95% CI, 1.02-1.64) with sleep disturbance had a significantly increased risk of CVD than those without; contrarily, men (AHR, 1.45; 95% CI, 1.09-1.95) and older adults (AHR, 1.51; 95% CI, 1.15-1.99) with sleep disturbance were associated with a significantly increased risk of all-cause mortality than those without. CONCLUSIONS: Our findings suggest that sleep disturbance is significantly associated with an increased risk of CVD and all-cause mortality in patients with new-onset type 2 diabetes.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Trastornos del Sueño-Vigilia/epidemiología , Adulto , Anciano , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/mortalidad , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/mortalidad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , República de Corea/epidemiología , Medición de Riesgo , Factores de Riesgo , Trastornos del Sueño-Vigilia/diagnóstico , Trastornos del Sueño-Vigilia/mortalidad , Factores de Tiempo
12.
BMC Cancer ; 20(1): 316, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32293356

RESUMEN

BACKGROUND: We investigated whether head and neck squamous cell carcinoma (HNSCC) patient-derived xenografts (PDXs) reaffirm patient responses to anti-cancer therapeutics. METHODS: Tumors from HNSCC patients were transplanted into immunodeficient mice and propagated via subsequent implantation. We evaluated established PDXs by histology, genomic profiling, and in vivo anti-cancer efficacy testing to confirm them as the authentic in vivo platform. RESULTS: From 62 HNSCCs, 15 (24%) PDXs were established. The primary cancer types were tongue (8), oropharynx (3), hypopharynx (1), ethmoid sinus cancer (1), supraglottic cancer (1), and parotid gland (1); six PDXs (40%) were established from biopsy specimens from advanced HNSCC. PDXs mostly retained donor characteristics and remained stable across passages. PIK3CA (H1047R), HRAS (G12D), and TP53 mutations (H193R, I195T, R248W, R273H, E298X) and EGFR, CCND1, MYC, and PIK3CA amplifications were identified. Using the acquisition method, biopsy showed a significantly higher engraftment rate when compared with that of surgical resection (100% [6/6] vs. 16.1% [9/56], P < 0.001). Specimens obtained from metastatic sites showed a significantly higher engraftment rate than did those from primary sites (100% [9/9] vs. 11.3% [6/53], P < 0.001). Three PDX models from HPV-positive tumors were established, as compared to 12 from HPV-negative (15.8% [3/19] and 27.9% [12/43] respectively, P = 0.311), suggesting that HPV positivity tends to show a low engraftment rate. Drug responses in PDX recapitulated the clinical responses of the matching patients with pan-HER inhibitors and pan-PI3K inhibitor. CONCLUSIONS: Genetically and clinically annotated HNSCC PDXs could be useful preclinical tools for evaluating biomarkers, therapeutic targets, and new drug discovery.


Asunto(s)
Afatinib/administración & dosificación , Aminopiridinas/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Redes Reguladoras de Genes , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Metotrexato/administración & dosificación , Morfolinas/administración & dosificación , Afatinib/farmacología , Aminopiridinas/farmacología , Animales , Biopsia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Amplificación de Genes , Variación Genética , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Metotrexato/farmacología , Ratones , Morfolinas/farmacología , Infecciones por Papillomavirus/tratamiento farmacológico , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/patología , Modelación Específica para el Paciente , Resultado del Tratamiento , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Int J Geriatr Psychiatry ; 35(3): 282-289, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31859411

RESUMEN

OBJECTIVES: The present study evaluated suicide risk within 1 year after discharge among older adults with stroke as a function of depression onset. METHOD: We used the Korean National Health Insurance Service-Senior cohort data and included first discharged patients with a stroke as the principal diagnosis. The comparison group was selected by a 1:2 case-control propensity score matching for age, sex, Charlson comorbidity index, and diagnosis year between 2005 and 2012. Suicide deaths were measured by code for causes of death from Statistics Korea, and the main outcome was suicide death within 1 year following discharge. An adjusted hazard ratio (AHR) of suicidal risk was measured using a Cox proportional hazard model. RESULTS: In the total sample of 128 286 older adults (aged 63-114 years), the higher suicidal risk was examined for stroke patients vs the comparison group (AHR = 1.4; 95% confidence interval [CI], 1.1-1.8). Stroke patients with depression had an increased suicide risk (AHR = 2.9; 95% CI, 1.8-4.8) but only for poststroke depression (AHR = 4.1; 95% CI, 1.8-9.5). Pre and poststroke depression suicidality (AHR = 4.8; 95% CI, 2.1-11.1) was also higher when compared to stroke patients without depression. CONCLUSIONS: Poststroke patients are at increased suicidal risk during 1 year following discharge. Furthermore, patients who were diagnosed with depression after a stroke are more likely to commit suicide than stroke patients without depression. This suggests a necessity for early suicide preventive intervention for stroke patients while considering depressive symptomology.


Asunto(s)
Suicidio , Anciano , Anciano de 80 o más Años , Humanos , Estudios Longitudinales , República de Corea/epidemiología , Estudios Retrospectivos , Factores de Riesgo
14.
Environ Res ; 191: 110033, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32810494

RESUMEN

Aquifer storage and recovery (ASR) technology has been adopted as a strategic water management tool. However, during the injection of oxic and organic carbon-containing water to the underground aquifers, severe phenomena such as clogging and groundwater deterioration have been reported. To prevent these severe phenomena, assimilable organic carbon (AOC) concentration has been controlled in the ASR applications by supporting bacteria growth potential. In this study, the AOC removal strategy was investigated in a simulated ASR system using an indigenous bacterium, Pseudomonas jinjuensis. AOC removal was evaluated under three different experimental conditions: (i) 30 °C and aerobic, (ii) 15 °C and aerobic, and (iii) 15 °C and anoxic. The effects of contact media such as sand and granular activated carbon on AOC removal efficiency were also investigated. Results show that under the 30 °C aerobic condition, P. jinjuensis could remove 99.8% (13 µg L-1) of AOC with soil. The variations in the organic fractions determined by liquid chromatography with organic carbon detector analysis were observed and showed trends similar to those of AOC determined by the flow cytometry method. The indirect injection method in ASR application was recommended due to the AOC removal benefit by soil indigenous bacterium.


Asunto(s)
Agua Subterránea , Purificación del Agua , Pseudomonas , Agua
15.
Environ Res ; 187: 109693, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32474311

RESUMEN

The sequential combination of nanofiltration (NF) and ettringite precipitation to manage sulfate-rich brine is proposed. In this study, NF experiments clearly demonstrated that sulfate-containing wastewater was effectively concentrated by the NF process (concentrate factor, CF > 5) with insignificant membrane fouling. Ettringite precipitation was implemented as an alternative to lime precipitation to process sulfate-rich brine resulting from the NF operation. More than 93% of the sulfate ions were removed by ettringite precipitation, whereas lime precipitation removed less than 28% under the same conditions due to the difference in their solubility. However, with highly concentrated NF brine (CF > 5), the pH and sulfate concentration of the supernatant were higher than the discharge limit. Therefore, optional blending of the supernatant after ettringite precipitation with the NF permeate was proposed to satisfy the discharge limit for sulfate. The sequential operation consisting of NF and ettringite precipitation enables sulfate-rich wastewater to be treated effectively, minimizing its negative impact by reducing the brine volume and enabling the water to be reused.


Asunto(s)
Sales (Química) , Purificación del Agua , Minerales , Sulfatos
16.
Int J Geriatr Psychiatry ; 34(11): 1565-1571, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31276241

RESUMEN

OBJECTIVES: We aimed to identify the impact of poverty on suicide risk in older adults. METHOD: The data used in this study was obtained from the National Health Insurance Service-Senior claims database from 2002 to 2013. A total of 558 147 individuals were followed for up to 12 years. Poverty was assessed from insurance premium levels, and causes of death were analysed by linking individuals' deaths to the data for causes of death from the National Statistics Office in South Korea. Cox proportional hazard models were used to analyse the associations between poverty and suicide deaths after adjustments for possible confounders. RESULTS: Among 558 147 older adults (aged 60-119 years), the poverty group had an increased risk of suicide compared with the high-income group (adjusted hazard ratio [AHR], 1.34; 95% confidence interval [CI], 1.22-1.47), and poverty-group males had a significantly higher risk of suicide than males in the high-income group (AHR, 1.50; 95% CI, 1.33-1.68). Adults aged 60 to 74 years in the poverty group had a higher risk of suicide than those with a high income in the same age group (AHR, 1.41; 95% CI, 1.27-1.57). However, no statistically significant income gradient was found for females or adults aged 75 years or older. CONCLUSIONS: Our findings revealed that poverty is a risk factor for death by suicide in older adults. Suicide prevention strategies for older adults should be specifically tailored by income level.


Asunto(s)
Pobreza/estadística & datos numéricos , Suicidio/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Humanos , Renta , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , República de Corea , Estudios Retrospectivos , Factores de Riesgo
17.
BMC Health Serv Res ; 19(1): 776, 2019 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-31666066

RESUMEN

BACKGROUND: In 2002, a voluntary diagnosis-related groups (DRGs) payment system was introduced in South Korea for seven disease groups, and participation in the DRGs was mandated for all hospitals beginning in 2013. The primary aim of this study was to compare results reflective of patient care between voluntary participation hospitals (VPHs) and mandatory participation hospitals (MPHs) governed by either the DRGs or fee-for-service (FFS) payment system. METHODS: We collected DRGs and FFS inpatient records (n=3,038,006) from the Health Insurance Review and Assessment for the period of July 2011 to July 2014 and compared length-of-stay, total medical costs, shifting services to an outpatient setting, and readmission rates according to payment system, time of DRGs implementation, and hospital type. We analyzed the effects of mandatory introduction in DRGs payment system on results for patient care and used generalized estimating equations with difference-in-difference methodology. RESULTS: Most notably, patients at MPHs had significantly shorter LOS and lower readmission rates than VPH patients after mandatory introduction of the DRGs. Shifting services to an outpatient setting was similar between the groups. CONCLUSIONS: Our findings suggest that the DRGs payment policy in Korea has decreased LOS and readmission rates. These findings support the continued implementation and enlargement of the DRGs payment system for other diseases in South Korea, given its potential for curbing unnecessary resource usage encouraged by FFS. If the Korean government deliberates on expansion of the DRGs to include other diseases with higher rates of complications, policymakers need to monitor deterioration of health care quality caused by fixed pricing.


Asunto(s)
Grupos Diagnósticos Relacionados/economía , Hospitales , Programas Obligatorios , Calidad de la Atención de Salud/estadística & datos numéricos , Adulto , Anciano , Planes de Aranceles por Servicios/economía , Femenino , Humanos , Revisión de Utilización de Seguros , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud , República de Corea , Adulto Joven
18.
Biosci Biotechnol Biochem ; 81(5): 958-965, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28110622

RESUMEN

Excessive body fat accumulation can result in obesity, which is a serious health concern. Kefir, a probiotic, has recently shown possible health benefits in fighting obesity. This study investigated the inhibitory effects of 0.1 and 0.2% kefir powder on fat accumulation in adipose and liver tissues of high-fat diet (HFD)-induced obese mice. Kefir reduced body weight and epididymal fat pad weight and decreased adipocyte diameters in HFD-induced obese mice. This was supported by decreased expression of genes related to adipogenesis and lipogenesis as well as reduced proinflammatory marker levels in epididymal fat. Along with reduced hepatic triacylglycerol concentrations and serum alanine transaminase and aspartate transaminase activities, genes related to lipogenesis and fatty acid oxidation were downregulated and upregulated, respectively, in liver tissue. Kefir also decreased serum triacylglycerol, total cholesterol, and low-density lipoprotein-cholesterol concentrations. Overall, kefir has the potential to prevent obesity.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/patología , Dieta Alta en Grasa/efectos adversos , Kéfir , Obesidad/inducido químicamente , Obesidad/patología , Adipocitos/efectos de los fármacos , Adipocitos/patología , Adipogénesis/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Tamaño de la Célula , Epidídimo , Lípidos/sangre , Lipogénesis/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Obesidad/sangre , Obesidad/metabolismo
19.
Int Arch Occup Environ Health ; 90(1): 109-116, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27804038

RESUMEN

PURPOSE: Work-related factors are one of the known risk factors for depression. Given that the ability to work is considered an important aspect of well-being and health status, we investigated the association between the loss of work ability and depression. We further examined the association stratified by employment status. METHODS: We used data from the Korea Welfare Panel Study. The dependent variable of the present study was depression, which is measured by the Center for Epidemiologic Studies Depression Scale. Work ability transition from the previous year was divided into three categories: maintained, loss, and complete loss. A linear mixed-effects model was performed for the analysis. RESULTS: The work ability loss group (ß = 2.071, p < 0.0002) and the work ability completely loss group (ß = 2.651, p = 0.015) had higher depression scores compared to those who maintained their work ability from the previous year. Specifically, those who lost their work ability and their job (ß = 3.685, p = 0.0068) had the highest depression scores compared to those who maintained their work ability and job. CONCLUSIONS: We found that those who lost their ability to work may be at risk of depression, and this finding was particularly prominent among those who also became unemployed. Therefore, psychological support is needed for these individuals to overcome the negative influence of the loss of work ability.


Asunto(s)
Depresión/psicología , Empleo/psicología , Trabajo/psicología , Adulto , Anciano , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , República de Corea , Factores de Riesgo , Evaluación de Capacidad de Trabajo , Adulto Joven
20.
Nano Lett ; 16(4): 2159-67, 2016 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-26918518

RESUMEN

In the past decade, nanomaterials have made their way into a variety of technologies in solar energy, enhancing the performance by taking advantage of the phenomena inherent to the nanoscale. Recent examples exploit plasmonic core/shell nanoparticles to achieve efficient direct steam generation, showing great promise of such nanoparticles as a useful material for solar applications. In this paper, we demonstrate a novel technique for fabricating bimetallic hollow mesoporous plasmonic nanoshells that yield a higher solar vapor generation rate compared with their solid-core counterparts. On the basis of a combination of nanomasking and incomplete galvanic replacement, the hollow plasmonic nanoshells can be fabricated with tunable absorption and minimized scattering. When exposed to sun light, each hollow nanoshell generates vapor bubbles simultaneously from the interior and exterior. The vapor nucleating from the interior expands and diffuses through the pores and combines with the bubbles formed on the outer wall. The lack of a solid core significantly accelerates the initial vapor nucleation and the overall steam generation dynamics. More importantly, because the density of the hollow porous nanoshells is essentially equal to the surrounding host medium these particles are much less prone to sedimentation, a problem that greatly limits the performance and implementation of standard nanoparticle dispersions.

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