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Cations in an electrolyte modulate microenvironments near the catalyst surface and affect product distribution from an electrochemical CO2 reduction reaction, and thus, their interaction with intermediate states has been tried to be probed. Herein, we directly observed the cation effect on *CO intermediates on the Cu(OH)2-derived catalyst in real time through operando surface-enhanced Raman spectroscopy at high overpotentials (-1.0 VRHE). Atop *CO peaks are composed of low-frequency binding *CO (*COLFB) and high-frequency binding *CO (*COHFB) because of their adsorption sites. These two *CO intermediates are found to have different sensitivities to the cation-induced field, and each *CO is proposed to be suitably stabilized for efficient C-C coupling. The proportions between *COHFB and *COLFB are dependent on the type of alkali cations, and the increases in the *COHFB ratio have a high correlation with selective C2H4 production under K+ and Cs+, indicating that *COHFB is the dominant and fast active species. In addition, as the hydrated cation size decreases, *COLFB is more sensitively red-shifted than *COHFB, which promotes C-C coupling and suppresses C1 products. Through time-resolved operando measurements, dynamic changes between the two *CO species are observed, showing the rapid initial adsorption of *COHFB and subsequently reaching a steady ratio between *COLFB and *COHFB.
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Unraveling the atomistic synergistic effects of nanoalloys on the electrocatalytic CO2 reduction reaction (eCO2RR), especially in the presence of copper, is of paramount importance. However, this endeavor encounters significant challenges due to the lack of the crystallographically determined atomic-level structure of appropriate monometallic and bimetallic analogues. Herein, we report a one-pot synthesis and structure characterization of a AuCu nanoalloy cluster catalyst, [Au15Cu4(DPPM)6Cl4(C≡CR)1]2+ (denoted as Au15Cu4). Single-crystal X-ray diffraction analysis reveals that Au15Cu4 comprises two interpenetrating incomplete, centered icosahedra (Au9Cu2 and Au8Cu3) and is protected by six DPPM, four halide, and one alkynyl ligand. The Au15Cu4 cluster and its closest monometal structural analogue, [Au18(DPPM)6Br4]2+ (denoted as Au18), as model systems, enable the elucidation of the atomistic synergistic effects of Au and Cu on eCO2RR. The results reveal that Au15Cu4 is an excellent eCO2RR catalyst in a gas diffusion electrode-based membrane electrode assembly (MEA) cell, exhibiting a high CO Faradaic efficiency (FECO) of >90%, and this efficiency is substantially higher than that of the undoped Au18 (FECO: 60% at -3.75 V). Au15Cu4 exhibits an industrial-level CO partial current density of up to -413 mA/cm2 at -3.75 V with the gas CO2-fed MEA, which is 2-fold higher than that of Au18. The density functional theory (DFT) calculations demonstrate that the synergistic effects are induced by Cu doping, where the exposed pair of AuCu dual sites was suggested for launching the eCO2RR process. Besides, DFT simulations reveal that these special dual sites synergistically coordinate a moderate shift in the d-state, thus enhancing its overall catalytic performance.
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AIMS: The study aimed to develop and evaluate the effects of a self-determination theory-based, nurse-led, physical activity programme for postmenopausal women with rheumatoid arthritis. METHODS: Between December 2019 and April 2020, this randomized controlled trial recruited 62 postmenopausal women with rheumatoid arthritis from a university-affiliated hospital in South Korea. The intervention group participated in a self-determination theory-based, nurse-led, physical activity programme that consisted of Tai Chi-based physical activity, a supportive psychosocial strategy, and interactive counselling for 16 weeks, and the control group continued to undergo their usual care. RESULTS: There were statistically significant group-by-time interactions in physical activity and perceived sarcopenia, which favoured the intervention group. Additionally, the intervention group showed significant improvements in the perceived therapeutic efficacy of physical activity, grip strength, walking speed, disease activity score, and health-related quality of life. CONCLUSIONS: The programme developed in this study can be an effective and feasible approach for postmenopausal women with rheumatoid arthritis in improving physical activity, selected osteosarcopenic outcomes, and health-related quality of life. Further research is required to investigate the long-term effects of this theory-based programme for postmenopausal women in diverse settings.
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Artritis Reumatoide , Calidad de Vida , Humanos , Femenino , Posmenopausia , Ejercicio Físico , Artritis Reumatoide/terapia , Artritis Reumatoide/psicología , República de CoreaRESUMEN
As demonstrated in prior studies, InSAR holds great potential for land cover classification, especially considering its wide coverage and transparency to climatic conditions. In addition to features such as backscattering coefficient and phase coherence, the temporal migration in InSAR signatures provides information that is capable of discriminating types of land cover in target area. The exploitation of InSAR signatures was expected to provide merits to trace land cover change in extensive areas; however, the extraction of suitable features from InSAR signatures was a challenging task. Combining time series amplitudes and phase coherences through linear and nonlinear compressions, we showed that the InSAR signatures could be extracted and transformed into reliable classification features for interpreting land cover types. The prototype was tested in mountainous areas that were covered with a dense vegetation canopy. It was demonstrated that InSAR time series signature analyses reliably identified land cover types and also recognized tracing of temporal land cover change. Based on the robustness of the developed scheme against the temporal noise components and the availability of advanced spatial and temporal resolution SAR data, classification of finer land cover types and identification of stable scatterers for InSAR time series techniques can be expected. The advanced spatial and temporal resolution of future SAR assets combining the scheme in this study can be applicable for various important applications including global land cover changes monitoring.
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Recent accumulating epidemiological evidence underlines the important role of environmental exposures on kidney diseases. Among environmental exposures, this study addresses "Green space," which has been recognized as one of the major environmental exposures at the population level. We review a total of seven epidemiological studies currently published on greenness and kidney disease. We also discuss knowledge gaps in the epidemiological evidence in relation to study design, greenness exposure index, emerging kidney outcomes, and inequalities. With an increase in public attention regarding environmental risks and climate change, an improved understanding of the beneficial effects of green space can play an important role in promoting kidney health.
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BACKGROUND: We analyzed trends in cancer incidence and regional disparities of eight major types of cancer in Korea. METHODS: This retrospective cohort study used the data of 17 cities/provinces from the Korea Central Cancer Registry (1999-2020) in South Korea. Age-standardized incidence rates (per 100,000 person-years), between-group variance (per 100,000 person-years)2, and annual percentage changes ( %) were calculated for the eight most common malignancies. Joinpoint regression was utilized to identify the points at which significant changes occur in cancer incidence or regional disparity trends over time to characterize these trends. RESULTS: The incidence of stomach cancer decreased as regional disparity decreased and that of colorectal cancer initially increased but recently declined, showing fluctuations in regional disparity. The incidence and regional disparity in liver cancer decreased. The incidence of lung cancer remained stable, with reduced regional disparities. The incidence of breast cancer rose with increasing regional disparity, whereas the incidence of cervical cancer decreased, accompanied by decreased regional disparity. A significant increase in prostate cancer was found, with initially reduced regional disparities but later showed a resurgence. The incidence of thyroid cancer fluctuated alongside variations in regional disparities. CONCLUSION: This study revealed cancer incidence and regional variations in each cancer type in Korea. More studies are needed to understand the underlying factors and potential interventions for reducing cancer incidence and addressing regional disparity.
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Neoplasias , Sistema de Registros , Humanos , República de Corea/epidemiología , Estudios Retrospectivos , Incidencia , Masculino , Femenino , Neoplasias/epidemiología , Sistema de Registros/estadística & datos numéricos , Persona de Mediana Edad , Disparidades en el Estado de Salud , Anciano , AdultoRESUMEN
AIM: This study aimed to examine a hypothetical model of physical activity (PA) and health outcomes related to sarcopenia in women with rheumatoid arthritis (RA) based on self-determination theory. DESIGN: Cross-sectional study. METHODS: This study included 214 women diagnosed with RA from the outpatient rheumatology department of a university-affiliated hospital in South Korea. Data were collected from September 2019 to August 2020 through structured questionnaires and anthropometric measurements and analysed using path analysis to test the hypothesized model. The primary health outcomes were perceived health status and sarcopenia-related health (thigh circumference, handgrip strength and sarcopenia risk). RESULTS: The final model's fit indices were adequate. Physical activity was directly affected by motivation for PA, while depression, self-efficacy for PA, health care provider's autonomy support and basic psychological needs satisfaction indirectly affected PA. Physical activity directly affected perceived health status and thigh circumference, while perceived sarcopenia risk and handgrip strength were directly affected by disease activity and age. PATIENT OR PUBLIC CONTRIBUTION: Patients were involved in a questionnaire-based survey.
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Artritis Reumatoide , Sarcopenia , Humanos , Femenino , Sarcopenia/diagnóstico , Fuerza de la Mano , Estudios Transversales , Artritis Reumatoide/complicaciones , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/psicología , Ejercicio Físico , Evaluación de Resultado en la Atención de SaludRESUMEN
Tibolone, a selective tissue estrogenic activity regulator, is a synthetic steroid with distinct pharmacological and clinical characteristics in contrast to conventional menopausal hormone therapy. Tibolone induces estrogenic activity in the brain, vagina, and bone but remains inactive in the endometrium and breast. In particular, several studies have investigated whether tibolone usage increases the risk of breast cancer. This study aims to determine the effects of tibolone on the breast by focusing on the relation between tibolone use and breast cancer. Our investigation emphasizes recent studies, particularly those based on Asian populations.
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This study investigated the lay perception of inequalities in society, healthcare utilization, and health in Korea. We also examined the association between socioeconomic status (SES) and perception of inequalities. Data from an online survey on the perception of health and healthcare inequalities related to cancer conducted between October 19, 2021, and November 12, 2021, were used. Data of 3,769 participants aged 20 to 74 years from 17 provinces were analyzed. We examined the perceived level of inequalities according to SES or residential area using frequency analysis, a t-test or analysis of variance (ANOVA), multiple linear regression analysis, and multiple logistic regression analysis. The mean score for perception of social inequality was 5.99 [Standard Deviation (SD) = 1.95] and that for perception of healthcare utilization inequality was 4.75 (SD = 1.96). The perception rate of health inequality according to SES and residential area was approximately 59 % and 61 %, respectively. Higher the income level, lower the level of perception of social inequalities ß = -0.22, p < 0.01). Higher the education level, higher the level of perception of healthcare utilization inequalities (ß = 0.21, p < 0.01). Higher the education level, higher the level of perception of health inequalities according to SES or residential area [adjusted odds ratio (aOR): 2.33 (95 % CI: 1.48, 3.66); aOR: 2.73 (95 % CI: 1.73, 4.31)]. Socioeconomic inequalities were observed in the perception of inequalities in healthcare utilization and health. Policymakers should establish policies to bridge the gap between perceived healthcare utilization inequalities and health inequalities. Future research should investigate the perception of healthcare utilization and health inequalities.
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Direct partial oxidation of methane to liquid oxygenates has been regarded as a potential route to valorize methane. However, CH4 activation usually requires a high temperature and pressure, which lowers the feasibility of the reaction. Here, we propose an electro-assisted approach for the partial oxidation of methane, using in-situ cathodically generated reactive oxygen species, at ambient temperature and pressure. Upon using acid-treated carbon as the electrocatalyst, the electro-assisted system enables the partial oxidation of methane in an acidic electrolyte to produce oxygenated liquid products. We also demonstrate a high production rate of oxygenates (18.9 µmol h-1) with selective HCOOH production. Mechanistic analysis reveals that reactive oxygen species such as âOH and âOOH radicals are produced and activate CH4 and CH3OH. In addition, unstable CH3OOH generated from methane partial oxidation can be additionally reduced to CH3OH on the cathode, and so-produced CH3OH is further oxidized to HCOOH, allowing selective methane partial oxidation.
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Muscular dysfunction in rheumatoid arthritis (RA) can affect the quality of life and comorbidities. We enrolled 320 patients with RA, and evaluated their muscle mass, grip strength, and physical performance. Seven (2.2%) and 21 RA patients (6.6%) had sarcopenia, as defined by the European and Asian Working Group for Sarcopenia (EWGS and AWGS), respectively; 54 patients (16.9%) were determined to have low muscle mass with normal muscle function, as defined by the EWGS; 38 patients (11.9%) reported sarcopenia by SARC-F questionnaire. Male sex (odds ratio (OR) 140.65), low body mass index (BMI) (OR 0.41), and use of tumor necrosis factor (TNF) inhibitors (OR 4.84) were associated with a low muscle mass as defined by the EWGS, while male sex, old age, and low BMI were associated with sarcopenia as defined by the AWGS. Old age (OR 1.11), high BMI (OR 1.13), and a high Disease Activity Score 28 (OR 1.95) were associated with sarcopenia as reported on the SARC-F. Male, low BMI, and use of TNF inhibitors were associated with a low muscle mass, while male sex, old age, and low BMI were associated with sarcopenia in patients with long-standing RA.
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We developed a simple and systematic method to fabricate optically tunable and thermally and chemically stable Au-Ag nanocrystal-based plasmonic metamaterials. An Ag nanocrystal-based metamaterial with desirable optical properties was fabricated via nanoimprinting and ligand-exchange process. Its optical properties were controlled by selectively substituting Ag atoms with Au atoms through a spontaneous galvanic replacement reaction. The developed Au-Ag-based metamaterials provide excellent tunable plasmonic properties required for various applications in the visible and near-infrared regions by controlling the Au-Ag composition according to the conditions of the galvanic displacement. Furthermore, their thermal and chemical stabilities significantly improved because of the protective Au thin layer on the surface. Using this developed process, chemically and thermally stable and flexible plasmonic metamaterials were successfully fabricated on a flexible polyester terephthalate substrate.
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In this work, we introduce a low cost, room-temperature and atmospheric pressure based chemical method to produce highly transparent, conductive, and flexible nano-mesh structured electrodes using Ag nanocrystals (NCs). Sequential treatments of ligand exchange and reduction processes were developed to engineer the optoelectronic properties of Ag NC thin films. Combinatorial analysis indicates that the origin of the relatively low conductivity comes from the non-metallic compounds that are introduced during ligand exchange. The reduction process successfully removed these non-metallic compounds, yielding structurally uniform, optically more transparent, dispersive, and electrically more conductive thin films. We optimized the design of Ag NC thin film mesh structures, and achieved low sheet resistance (9.12 Ω â¡-1), high optical transmittance (94.7%), and the highest figure of merit (FOM) of 6.37 × 10-2. Solution processed flexible transparent heaters, touch pads, and wearable sensors are demonstrated, emphasizing the potential applications of Ag NC transparent electrodes in multifunctional sensors and devices.
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BACKGROUND/AIMS: Suppression of gastrointestinal (GI) peristalsis during GI endoscopy commonly requires antispasmodic agents such as hyoscine butylbromide, atropine, glucagon, and cimetropium bromide. This study examined the efficacy of oral phloroglucin for the suppression of peristalsis, its impact on patient compliance, and any associated complications, and compared it with intravenous or intramuscular cimetropium bromide administration. METHODS: This was a randomized, investigator-blind, prospective comparative study. A total of 172 patients were randomized into two groups according to the following medications administered prior to upper endoscopy: oral phloroglucin (group A, n=86), and cimetropium bromide (group B, n=86). The numbers and the degrees of peristalsis events at the antrum and second duodenal portion were assessed for 30 seconds. RESULTS: A significantly higher number of gastric peristalsis events was observed in group A (0.49 vs. 0.08, p<0.001), but the difference was not clinically significant. No significant difference between both groups was found in the occurrence of duodenal peristalsis events (1.79 vs. 1.63, p=0.569). The incidence of dry mouth was significantly higher with cimetropium bromide than with phloroglucin (50% vs. 15.1%, p<0.001). CONCLUSIONS: Oral phloroglucin can be used as an antispasmodic agent during upper endoscopy, and shows antispasmodic efficacy and adverse effects similar to those of cimetropium bromide.
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BACKGROUND/AIMS: As life expectancy has increased, the number of elderly patients who need long-term care has grown rapidly. Mortality in patients with colitis in long-term care facilities (LTCFs) is increasing. We intend to investigate the main causes of colitis in LTCFs compared to those of colitis in local communities, and to identify the clinical features and risk factors of patients with colitis in LTCFs. METHODS: We retrospectively analyzed epidemiology, medical conditions, laboratory values, diagnoses, and clinical courses of elderly patients aged ≥65 who were admitted to the Ewha Womans University hospital with colitis between January 2007 and July 2012. RESULTS: Patients with colitis in LTCFs (n=20) were compared with elderly patients with colitis in local communities (n=154). Fifty-five percent of colitis in LTCFs was caused by Clostridium difficile infection (CDI), 30% was due to ischemic colitis, and 15% was due to non-specific colitis. Non-specific colitis was the most common (63%) in the community group. Clinical outcomes were also significantly different between both groups: higher mortality (10.0% vs. 0.64%, P=0.021), higher requirement for intensive care units care (50.0% vs. 18.8%, P<0.01) in LTCFs group. In univariate analysis, the most significant risk factor for death in patients in LTCFs was decreased mental faculties. CONCLUSIONS: Patients in LTCFs showed worse clinical outcomes and a much higher prevalence of CDI compared to patients from local communities. We suggest early and active evaluation, such as endoscopic examination, for differential diagnosis in patients in LTCFs.
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Hemorrhagic cystitis is defined by lower urinary tract symptoms that include dysuria, hematuria, and hemorrhage and is caused by viral or bacterial infection or chemotherapeutic agents. Reports of hemorrhagic cystitis caused by non-typhoidal salmonella (NTS) are extremely rare. We report a case of a 41-year-old man with hemorrhagic cystitis from NTS that caused massive bleeding and shock. The patient was hospitalized for uncontrolled diabetes and obstructive uropathy related to severe cystitis. A urine culture was positive for group D NTS. This case demonstrated that hemorrhagic cystitis in a patient with a risk factor such as diabetes can be a manifestation of local extra-intestinal NTS infection.