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Background@#The purpose of this study is to analyze the current status and factors of elderly patients’ hospitalization for hip replacement, knee replacement, and general spine surgery. @*Methods@#National health insurance data in 2018 was provided by the National Health Insurance Service. We used multiple regression to analyze factors associated with the medical utilization of hip replacement, knee replacement, and general spine surgery in elderly patients over 65 years old. The dependent variables are the length of stay and total health expenditure. The independent variables are the demographic-social factors (sex, age, region, insurance type, income level) and surgery-related factors (institution type, location of the hospital, surgery classification). @*Results@#The most common factor affecting surgery was the location of medical institutions. Compared with the medical institutions located in metropolitan, the length of stay in rural medical institutions was higher and total health expenditure was lower. The lower quartile of income, the higher the length of stay and total health expenditure. In addition, the variables of age, type of health insurance, and type of medical institution were statistically significant. @*Conclusion@#In this study, we confirmed the effect of sociodemographic factors and medical institution factors on the Healthcare Utilization of spinal and joint surgery.
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Background@#Based on the importance of ceasing smoking programs to control the regional disparity of smoking behavior in Korea, this study aims to reveal the variation of smoke rate and determinants of it for 229 provinces. An evaluation of the relative efficiency of the cease smoking program under the consideration of regional characteristics was followed. @*Methods@#The main sources of data are the Korean Statistical Information Service and a national survey on the expenditure of public health centers. Multivariate regression is performed to figure the determinants of regional variation of smoking rate. Based on the result of the regression model, clustering analysis was conducted to group 229 regions by their characteristics. Three clusters were generated. Using data envelopment analysis (DEA), relative efficiency scores are calculated. Results from the pooled model which put 229 provinces in one model to score relative efficiency were compared with the cluster-separated model of each cluster. @*Results@#First, the maximum variation of the smoking rate was 16.9%p. Second, sex ration, the proportion of the elder, and high risk drinking alcohol behavior have a significant role in the regional variation of smoking. Third, the population and proportion of the elder are the main variables for clustering. Fourth, dissimilarity on the results of relative efficiency was found between the pooled model and cluster-separated model, especially for cluster 2. @*Conclusion@#This study figured regional variation of smoking rate and its determinants on the regional level. Unconformity of the DEA results between different models implies the issues on regional features when the regional evaluation performed especially on the programs of public health centers.
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Flow-electrode capacitive deionization (FCDI) is novel capacitive deionization (CDI) technology that exhibits continuous deionization and a high desalting efficiency. A flow-electrode with high capacitance and low resistance is required for achieving an efficient FCDI system with low energy consumption. For developing high-performance flow-electrode, studies should be conducted considering porous materials, conductive additives, and electrolytes constituting the flow-electrode. Here, we evaluated the desalting performances of flow-electrodes with spherical activated carbon and aqueous electrolytes containing various concentrations of NaCl in the FCDI unit cell for confirming the effect of salt concentration on the electrolyte of a flow-electrode on desalting efficiency. We verified the necessity of a moderate amount of salt in the flow-electrode for compensating for the reduction in the performance of the flow-electrode, attributed to the resistance of water used as the electrolyte. Simultaneously, we confirmed the potential use of salt water with a high salt concentration, such as seawater, as an aqueous electrolyte for the flow-electrode.
Subject(s)
Salinity , Water Purification , Electric Capacitance , Electrodes , Sodium ChlorideABSTRACT
We report the synthesis of carbon nanowires (CNWs) via chemical vapor deposition using catalytic decomposition of ethanol on nanosized transition metals such as Co, Fe, and Ni. Dip-coating process was used for the formation of catalytic nanoparticles, inducing the growth of CNWs on the surface of the carbon fiber paper (CFP). The liquid ethanol used as carbon source was atomized by an ultrasonic atomizer and subsequently flowed into the reactor that was heated up to a synthesis temperature of 600-700°C. Microscopic images show that CNWs of <50 nm were densely synthesized on the surface of the CFP. Raman spectra reveal that a higher synthesis temperature leads to the growth of higher crystalline CNWs. In addition, we demonstrate the successful decoration of platinum nanoparticles on the surface of the prepared CNWs/CFP using the electrochemical deposition technique.
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We demonstrate a simple and reproducible technique to synthesize crystalline and superconducting In-Sn intermetallic nanowires sheathed in carbon nanotubes (CNTs). The method is based on the catalytic reaction of C(2)H(2) over a mixture of both SnO(2) and In(2)O(3) particles. Importantly, tetragonal ß-In(3)Sn and hexagonal γ-InSn(4) nanowires with diameters of less than 100 nm are selectively synthesized at different SnO(2) to In(2)O(3) weight ratios. CNTs may serve as cylindrical nanocontainers for continuous growth of liquid-phased In(1-x)Sn(x) nanowires during growth process as well as for their solidification into In-Sn intermetallic nanowires during the cooling process. Microscopic and spectroscopic analyses clearly reveal evidence of a core-shell structure of the CNT-sheathed In-Sn intermetallic nanowires. Magnetization measurements show that the superconducting In-Sn nanowires have a critical magnetic field higher than the value of their bulk intermetallic compounds. Our method can be adopted to the nanofabrication of analogous binary and ternary alloys.
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As a potential adsorbent for humidity control, the mesoporous silica, SBA-15, with various pore sizes that was synthesized hydrothermally at different temperatures was examined by measuring the rate of water adsorption under ambient condition, 2.53 kPa H2O and 30 degrees C. The adsorption saturation quantity and the diffusion coefficient of water were changed consistently with the micropore fraction in SBA-15 obtained from the t-plot method. The diffusion of water into the SBA-15 was very similar to that on either zeolite A or Y because of the presence of complimentary pore.
