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Nam JY, Hwang KS, Kim HC, Jeong H, Kim H, Jwa E, Yang S, Choi J, Kim CS, Han JH, Jeong N. Assessing the behavior of the feed-water constituents of a pilot-scale 1000-cell-pair reverse electrodialysis with seawater and municipal wastewater effluent. WATER RESEARCH 2019; 148:261-271. [PMID: 30388527 DOI: 10.1016/j.watres.2018.10.054] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 10/20/2018] [Accepted: 10/20/2018] [Indexed: 06/08/2023]
Abstract
Reverse electrodialysis (RED) has vast potential as a clean, nonpolluting, and sustainable renewable energy source; however, pilot-scale RED studies employing real waters remain rare. This study reports the largest RED (1000 cell pairs, 250 m2) with municipal wastewater effluent (1.3-5.7 mS/cm) and seawater (52.9-53.8 mS/cm) as feed solutions. The RED stack was operated at a velocity of 1.5 cm/s and the pilot plant produced 95.8 W of power (0.38 W/m2total membrane or 0.76 W/m2cell pair). During operation of the RED, the inlet design of the stack, comprising thin spacers, and the water dissociation reaction at the cathode were revealed as vulnerabilities of the stack. Specifically, pressure drops at the fluid inlet parts had the most detrimental effects on power output due to clogged spacers around the inlet parts. In addition, precipitates resulting in inorganic fouling were inevitable during the water dissociation reaction due to significant potential generated by the stack in the cathode chamber. Na+ and Cl- accounted for the majority of ions transferred from seawater to wastewater effluent through ion exchange membranes (IEMs). Moreover, some divalent cations in seawater, Mg2+ and Ca2+, were also transferred to the wastewater effluent. Some organics with relatively low molecular weights in the wastewater effluent passed through the IEMs, and their hydrophobic properties elevated the specific UV absorbance (SUVA) level in the seawater.
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Kim DW, Kim HC, Kim BH, Kim MJ, Shin E. Expression of ATP transporters is associated with histologic regression of rectal carcinoma after neoadjuvant chemoradiotherapy. Transl Cancer Res 2018. [DOI: 10.21037/tcr.2018.12.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kim HC, Bandettini PA, Lee JH. Deep neural network predicts emotional responses of the human brain from functional magnetic resonance imaging. Neuroimage 2018; 186:607-627. [PMID: 30366076 DOI: 10.1016/j.neuroimage.2018.10.054] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 08/15/2018] [Accepted: 10/21/2018] [Indexed: 10/28/2022] Open
Abstract
An artificial neural network with multiple hidden layers (known as a deep neural network, or DNN) was employed as a predictive model (DNNp) for the first time to predict emotional responses using whole-brain functional magnetic resonance imaging (fMRI) data from individual subjects. During fMRI data acquisition, 10 healthy participants listened to 80 International Affective Digital Sound stimuli and rated their own emotions generated by each sound stimulus in terms of the arousal, dominance, and valence dimensions. The whole-brain spatial patterns from a general linear model (i.e., beta-valued maps) for each sound stimulus and the emotional response ratings were used as the input and output for the DNNP, respectively. Based on a nested five-fold cross-validation scheme, the paired input and output data were divided into training (three-fold), validation (one-fold), and test (one-fold) data. The DNNP was trained and optimized using the training and validation data and was tested using the test data. The Pearson's correlation coefficients between the rated and predicted emotional responses from our DNNP model with weight sparsity optimization (mean ± standard error 0.52 ± 0.02 for arousal, 0.51 ± 0.03 for dominance, and 0.51 ± 0.03 for valence, with an input denoising level of 0.3 and a mini-batch size of 1) were significantly greater than those of DNN models with conventional regularization schemes including elastic net regularization (0.15 ± 0.05, 0.15 ± 0.06, and 0.21 ± 0.04 for arousal, dominance, and valence, respectively), those of shallow models including logistic regression (0.11 ± 0.04, 0.10 ± 0.05, and 0.17 ± 0.04 for arousal, dominance, and valence, respectively; average of logistic regression and sparse logistic regression), and those of support vector machine-based predictive models (SVMps; 0.12 ± 0.06, 0.06 ± 0.06, and 0.10 ± 0.06 for arousal, dominance, and valence, respectively; average of linear and non-linear SVMps). This difference was confirmed to be significant with a Bonferroni-corrected p-value of less than 0.001 from a one-way analysis of variance (ANOVA) and subsequent paired t-test. The weights of the trained DNNPs were interpreted and input patterns that maximized or minimized the output of the DNNPs (i.e., the emotional responses) were estimated. Based on a binary classification of each emotion category (e.g., high arousal vs. low arousal), the error rates for the DNNP (31.2% ± 1.3% for arousal, 29.0% ± 1.7% for dominance, and 28.6% ± 3.0% for valence) were significantly lower than those for the linear SVMP (44.7% ± 2.0%, 50.7% ± 1.7%, and 47.4% ± 1.9% for arousal, dominance, and valence, respectively) and the non-linear SVMP (48.8% ± 2.3%, 52.2% ± 1.9%, and 46.4% ± 1.3% for arousal, dominance, and valence, respectively), as confirmed by the Bonferroni-corrected p < 0.001 from the one-way ANOVA. Our study demonstrates that the DNNp model is able to reveal neuronal circuitry associated with human emotional processing - including structures in the limbic and paralimbic areas, which include the amygdala, prefrontal areas, anterior cingulate cortex, insula, and caudate. Our DNNp model was also able to use activation patterns in these structures to predict and classify emotional responses to stimuli.
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Shin WY, Kim HC, Lee T, Jeon DH, Ha KH, Kim DJ, Chang HJ. Combined effects of diabetes and low household income on mortality: a 12-year follow-up study of 505 677 Korean adults. Diabet Med 2018; 35:1345-1354. [PMID: 29851428 DOI: 10.1111/dme.13695] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/29/2018] [Indexed: 12/20/2022]
Abstract
AIM To examine the effects of diabetes, low income and their combination on mortality in the Korean population. METHODS We analysed a total of 505 677 people (53.9% male) aged 40-79 years old from the National Health Insurance Service-National Health Screening (NHIS-HEALS) cohort. Ten levels of household income were used as indicators of economic status. Diabetes was defined as elevated fasting blood glucose (≥ 6.9 mmol/l) and/or use of glucose-lowering drugs or insulin. Covariates of age, sex, BMI, smoking and Charlson Comorbidity Index were determined at baseline. Outcomes were total and cause-specific mortality over 12 years. Cox's proportional hazard regression models were used to estimate hazard ratios (HRs) for mortality according to the presence of diabetes, household income and their combination. RESULTS Lower household income was associated with higher mortality from all causes, cardiovascular disease, cancer and non-cancer non-cardiovascular causes. Excessive mortality due to low incomes was observed in both people with and without diabetes. In men, the adjusted HR [95% confidence interval (CI)] of mortality was 1.38 (1.34 to 1.42) for low-income only, 1.48 (1.42 to 1.55) for diabetes only and 1.95 (1.86 to 2.05) for diabetes and low-income combined, relative to the normal glucose and high income group. Corresponding HR (95% CI) in women were 1.19 (1.14 to 1.24), 1.54 (1.44 to 1.64) and 1.87 (1.75 to 2.01), respectively. CONCLUSION Both low household income and the presence of diabetes independently increase the risk of mortality, but their combined effects on mortality may be different between men and women.
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Kim JY, Kim HC, Yang GS. Mass spectra of singly heavy baryons in a self-consistent chiral quark-soliton model. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.98.054004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Won KB, Kim HC, Lee BK, Chang HJ. P738Association between insulin resistance estimated by triglyceride glucose index and arterial stiffness. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy564.p738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Gnatiuc L, Herrington WG, Halsey J, Tuomilehto J, Fang X, Kim HC, De Bacquer D, Dobson AJ, Criqui MH, Jacobs DR, Leon DA, Peters SAE, Ueshima H, Sherliker P, Peto R, Collins R, Huxley RR, Emberson JR, Woodward M, Lewington S, Aoki N, Arima H, Arnesen E, Aromaa A, Assmann G, Bachman DL, Baigent C, Bartholomew H, Benetos A, Bengtsson C, Bennett D, Björkelund C, Blackburn H, Bonaa K, Boyle E, Broadhurst R, Carstensen J, Chambless L, Chen Z, Chew SK, Clarke R, Cox C, Curb JD, D'Agostino R, Date C, Davey Smith G, De Backer G, Dhaliwal SS, Duan XF, Ducimetiere P, Duffy S, Eliassen H, Elwood P, Empana J, Garcia-Palmieri MH, Gazes P, Giles GG, Gillis C, Goldbourt U, Gu DF, Guasch-Ferre M, Guize L, Haheim L, Hart C, Hashimoto S, Hashimoto T, Heng D, Hjermann I, Ho SC, Hobbs M, Hole D, Holme I, Horibe H, Hozawa A, Hu F, Hughes K, Iida M, Imai K, Imai Y, Iso H, Jackson R, Jamrozik K, Jee SH, Jensen G, Jiang CQ, Johansen NB, Jorgensen T, Jousilahti P, Kagaya M, Keil J, Keller J, Kim IS, Kita Y, Kitamura A, Kiyohara Y, Knekt P, Knuiman M, Kornitzer M, Kromhout D, Kronmal R, Lam TH, Law M, Lee J, Leren P, Levy D, Li YH, Lissner L, Luepker R, Luszcz M, MacMahon S, Maegawa H, Marmot M, Matsutani Y, Meade T, Morris J, Morris R, Murayama T, Naito Y, Nakachi K, Nakamura M, Nakayama T, Neaton J, Nietert PJ, Nishimoto Y, Norton R, Nozaki A, Ohkubo T, Okayama A, Pan WH, Puska P, Qizilbash N, Reunanen A, Rimm E, Rodgers A, Saitoh S, Sakata K, Sato S, Schnohr P, Schulte H, Selmer R, Sharp D, Shifu X, Shimamoto K, Shipley M, Silbershatz H, Sorlie P, Sritara P, Suh I, Sutherland SE, Sweetnam P, Tamakoshi A, Tanaka H, Thomsen T, Tominaga S, Tomita M, Törnberg S, Tunstall-Pedoe H, Tverdal A, Ueshima H, Vartiainen E, Wald N, Wannamethee SG, Welborn TA, Whincup P, Whitlock G, Willett W, Woo J, Wu ZL, Yao SX, Yarnell J, Yokoyama T, Yoshiike N, Zhang XH. Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies. Lancet Diabetes Endocrinol 2018; 6:538-546. [PMID: 29752194 PMCID: PMC6008496 DOI: 10.1016/s2213-8587(18)30079-2] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/20/2018] [Accepted: 02/26/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men. METHODS In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes. RESULTS Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes. INTERPRETATION Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained. FUNDING UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).
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Maeng SK, You SH, Nam JY, Ryu H, Timmes TC, Kim HC. The growth of Scenedesmus quadricauda in RO concentrate and the impacts on refractory organic matter, Escherichia coli, and trace organic compounds. WATER RESEARCH 2018; 134:292-300. [PMID: 29433079 PMCID: PMC6744953 DOI: 10.1016/j.watres.2018.01.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 01/12/2018] [Accepted: 01/13/2018] [Indexed: 05/31/2023]
Abstract
This study achieves a better operational simplicity for the phycoremediation of reverse osmosis (RO) concentrate using Scenedesmus quadricauda microalgae. Under continuous illumination with CO2 supplementation, algal growth in the RO concentrate resulted in a conversion of polymeric organic matter (a mixture of humic substances and polysaccharides) to biodegradable fractions and their prompt removal along with inorganic nutrients (NO3- and PO43-). The algal-induced degradation of humic-like substances which are typically refractory to microbial decomposition was demonstrated in an indirect manner. In this study, we also investigated the effects of algal treatment on the growth of Escherichia coli and removal of trace organic compounds (TOrCs) from the RO concentrate. Our results indicate that algal treatment of the RO concentrate using aeration with 10% (v/v) CO2 under continuous illumination is highly feasible as a safe and inexpensive technology to remove non- or slowly-biodegradable organic matter, reduce enteric bacteria, and attenuate TOrCs in wastewater. However, the results should not be generalized, but critically discussed, due to limitations of using the synthetic RO concentrate in evaluating the performance of wastewater remediation with microalgae.
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Choi IH, Jang SY, Kim HC, Huh S. In 6S 7 nanoparticle-embedded and sulfur and nitrogen co-doped microporous carbons derived from In(tdc) 2 metal-organic framework. Dalton Trans 2018; 47:1140-1150. [PMID: 29271458 DOI: 10.1039/c7dt03910g] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Indium sulfide nanoparticle (NP)-embedded microporous carbons co-doped with S- and N-dopants are easily prepared by a direct carbonization of the as-prepared In(iii)-based metal-organic framework (In-MOF), [Et2NH2][In(tdc)2]·DEF, containing ditopic S-containing 2,5-thiophenedicarboxylate (tdc2-) bridging linkers as a potential source of S-dopant. The charge on the anionic framework of [In(tdc)2]- is balanced by Et2NH2+, which is also a potential N-dopant. Simultaneous embedding of In-based NPs, S-, and N-co-doping is achieved in a simple single step carbonization of In-MOF. Three porous carbon materials (PCMs), PCM-700, PCM-800, and PCM-900, are obtained from the carbonization of In-MOF at 700, 800, and 900 °C, respectively. The gas sorption analysis indicates them as good CO2 sorbents. The photocatalytic degradation of methyl orange by PCMs under visible light irradiation is also effectively operable owing to the photocatalytically active semiconducting indium sulfide NP with a small bandgap. The main component of indium sulfide NPs is revealed as In6S7 based on the powder X-ray diffraction pattern. Small amounts of metallic In and In2S3 are also observed. The specific capacitances of PCMs are also estimated from the galvanostatic charge/discharge curves. PCM-900 exhibits the highest gravimetric specific capacitance of 99.0 F g-1 at a current density of 0.05 A g-1.
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Ly QV, Kim HC, Hur J. Tracking fluorescent dissolved organic matter in hybrid ultrafiltration systems with TiO2/UV oxidation via EEM-PARAFAC. J Memb Sci 2018. [DOI: 10.1016/j.memsci.2017.12.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Yu MS, Choi CH, Jung MS, Kim HC. Correlation between septal body size and inferior turbinate hypertrophy on computerised tomography scans in fifty patients: A radiological analysis. Clin Otolaryngol 2018; 43:952-955. [PMID: 29377481 DOI: 10.1111/coa.13073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2018] [Indexed: 11/28/2022]
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Duong TH, Kim HC. Extremely Simple and Rapid Fabrication of Flexible Transparent Electrodes Using Ultralong Copper Nanowires. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.7b04709] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Park SI, Chung SH, Kim HC, Lee SG, Lee SJ, Kim H, Kim H, Jeong SW. Prolonged heating of Fe3O4–Au hybrid nanoparticles in a radiofrequency solenoid coil. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.11.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Kim HC. Photostimulation of sequential degradation and assimilation of recalcitrant carbonaceous organics in Scenedesmus quadricauda. Process Biochem 2018. [DOI: 10.1016/j.procbio.2017.11.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kim HC, Huh S, Lee DN, Kim Y. Selective carbon dioxide sorption by a new breathing three-dimensional Zn-MOF with Lewis basic nitrogen-rich channels. Dalton Trans 2018; 47:4820-4826. [DOI: 10.1039/c7dt04134a] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A CO2 selective dynamic three-dimensional MOF, [Zn2(μ4-3,3′-PDBA)2(μ2-bpa)]3·(DMF)5(H2O)13, shows an unusual 3(2 + 1)-fold interpenetrated structure and phenomenal hysteretic behavior in CO2 sorption.
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Kim HC, Kim E, Ha TL, Lee SG, Lee SJ, Jeong SW. Highly stable and reduction responsive micelles from a novel polymeric surfactant with a repeating disulfide-based gemini structure for efficient drug delivery. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.11.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Tran NH, Duong TH, Kim HC. A fast fabrication of copper nanowire transparent conductive electrodes by using pulsed laser irradiation. Sci Rep 2017; 7:15093. [PMID: 29118427 PMCID: PMC5678115 DOI: 10.1038/s41598-017-15559-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 10/12/2017] [Indexed: 11/16/2022] Open
Abstract
Copper nanowires have shown promise for use in next-generation conducting materials for transparent electrodes owing to their low sheet resistance, natural abundance, and high transmittance properties. Additionally, copper nanowires can be easily synthesized via low-cost solution-based processes. However, copper requires a uniform film to coat the nanowires on the substrate and removing film former residue in the post-treatment process remains a challenge. This lead to the high cost and complexity of fabricating transparent electrode. In this study, we demonstrate a simple, time-saving production method using a combination of laser irradiation and acid dipping to fabricate high-quality copper nanowire transparent electrodes. Preparation of electrodes was achieved by scanning pulsed laser on a copper nanowire film and then dipping in glacial acetic acid. The electrode exhibited excellent properties and the film former was totally erased from the electrode surface. Moreover, to demonstrate their capability, the as-fabricated electrodes were applied in touch-sensor fabrication.
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Maeng SK, Timmes TC, Kim HC. Characteristics of flocs formed by polymer-only coagulation in water treatment and their impacts on the performance of downstream membrane separation. ENVIRONMENTAL TECHNOLOGY 2017; 38:2601-2610. [PMID: 27937736 DOI: 10.1080/09593330.2016.1271460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 09/19/2016] [Indexed: 06/06/2023]
Abstract
Two different quaternary amine polymers were examined as primary coagulants for the removal of natural organic matter (NOM) and concurrent production of flocs favorable for downstream membrane separation. The primary issue explored was the relationship between various coagulation conditions on the floc characteristics and the subsequent performance of microfiltration when filtering coagulated NOM. The size distribution and morphological properties of flocs formed through the coagulation of NOM were characterized and the effects of polymer type and dose on these characteristics were also examined. Coagulation of NOM using polydiallyldimethyl-ammonium chloride (pDADMAC) produced looser and less settleable flocs compared to dosing the equivalent amount of epichlorohydrin/dimethylamine (epi/DMA). This was associated with the formation of a relatively denser cake layer on the top of the membrane for the filtration of NOM coagulated with epi/DMA. The charge neutralization coagulation condition with the polymers removed almost all of the fouling tendency that had occurred when filtering raw NOM. The median diameter and the fractal dimension of the flocs produced increased as the zeta potential approached zero, which resulted in the formation of a cake layer that was easily removed from the surface of the membrane.
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Ha KH, Kim B, Choi H, Kim DJ, Kim HC. Cardiovascular events associated with second-line anti-diabetes treatments: analysis of real-world Korean data. Diabet Med 2017; 34:1235-1243. [PMID: 28523719 DOI: 10.1111/dme.13384] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/15/2017] [Indexed: 12/29/2022]
Abstract
AIM To compare the risks of cardiovascular disease (CVD) and all-cause mortality associated with sulfonylurea (SU), dipeptidyl peptidase-4 inhibitor (DPP4i) and thiazolidinedione (TZD) as add-on medications to metformin (MET) therapy in people with Type 2 diabetes. METHODS We identified 40 263 individuals who used SU (n = 11 582), DPP4i (n = 26 623) or TZD (n = 2058) in addition to MET between January 2013 and June 2015 from the database of the Korean National Health Insurance, the single-payer healthcare system in South Korea. Cox proportional hazard models were used to estimate hazard ratios for major CVD event (coronary artery disease, heart failure, stroke or transient ischaemic attack) development and all-cause mortality by second-line anti-diabetes medication type. Age, sex, duration of MET monotherapy, calendar year and comorbid conditions were adjusted as potential confounders. RESULTS The observed numbers of CVD events (total observed person-time) were 485 (18 778 person-years) for MET + SU, 744 (40 374 person-years) for MET + DPP4i and 60 (3014 person-years) for MET + TZD users. Compared with MET + SU users, the fully adjusted hazard ratios for CVD events were 0.79 [95% confidence interval (CI): 0.71-0.89] for MET + DPP4i users and 0.85 (95% CI: 0.65-1.11) for MET + TZD users. The corresponding hazard ratios for all-cause mortality were 0.84 (95% CI: 0.66-1.07) for MET + DPP4i users and 0.67 (95% CI: 0.35-1.28) for MET + TZD users. CONCLUSION Analysis of Korea National Health Insurance database showed that MET + DPP4i treatment for diabetes had a lower CVD risk than MET + SU treatment.
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So SH, Choi IH, Kim HC, Maeng SK. Seasonally related effects on natural organic matter characteristics from source to tap in Korea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 592:584-592. [PMID: 28320524 DOI: 10.1016/j.scitotenv.2017.03.063] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 03/05/2017] [Accepted: 03/07/2017] [Indexed: 06/06/2023]
Abstract
In this study, natural organic matter (NOM) characteristics were investigated over three years of monthly monitoring to determine the effect of seasonal variations on NOM levels from source to tap. Liquid chromatography with organic carbon detection (LC-OCD) was used to determine NOM characteristics and the level of reduction of biodegradable dissolved organic carbon (BDOC). The average dissolved organic matter concentration in the source water (Lake Paldang, Korea) was not significantly different between summer and winter. However, the distribution of NOM components, such as biopolymers, building blocks, low molecular weight (MW) neutrals and acids, identified by LC-OCD, varied seasonally. While high MW NOM was preferentially removed by coagulation/sedimentation/rapid sand filtration (CSR), no seasonal effects were observed on the removal of high MW NOM. CSR and biological activated carbon (BAC) filtration showed a better efficiency of BDOC removal in winter and summer, respectively. High concentrations of chlorine used in the treatment plants in summer resulted in 10% higher DOC concentrations during disinfection. Overall NOM removal efficiencies from source to tap were 45% and 35% for summer and winter, respectively. Principal component analysis also indicated that seasonal variations (principal component 1) showed the strongest positive correlation with the overall performance of water treatment. The long-term monitoring of drinking water treatment processes showed that seasonal variations were important factors affecting NOM characteristics during water treatment.
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Yang HS, Kim Y, Cho SY, Nam YS, Oh TS, Park KS, Kim HC, Lee HJ. Fluoroquinolone Resistance Mechanisms by Molecular Epidemiologic Study of Ciprofloxacin-Nonsusceptible Escherichia coli Sequence Types Isolated from Clinical Specimens in a Tertiary Care University Hospital in Korea: Emergence of Clone ST131, 2006-2008. ANNALS OF CLINICAL AND LABORATORY SCIENCE 2017; 47:511-515. [PMID: 28801381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
To investigate the sequence types (STs) and fluoroquinolone resistance related mutations among ciprofloxacin (CIP)-non-susceptible extended-spectrum β-lactamase (ESBL)-producing E. coli isolated from Korean patients from 2006-2008. The prevalence of fluoroquinolone resistance-determining region (QRDR) mutations in gyrA, gyrB, parC, and parE and plasmid-mediated quinolone resistance (PMQR) genes were also studied. Multilocus sequence typing (MLST) was performed to identify STs. The most common ST was ST131 (33/51, 64.7%). All isolates, except one isolate, showed three mutations at codons 83 (S83L) and 87 (S87N) in gyrA and 80 (S80I) in parC The prevalence of ST131 in our hospital was much higher than reported in other Asian studies during a similar time period. The mutations found in ST131 were concordant with other studies.
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Jang JK, Kwak SW, Ha JH, Kim HC. Anatomical relationship of maxillary posterior teeth with the sinus floor and buccal cortex. J Oral Rehabil 2017; 44:617-625. [PMID: 28547776 DOI: 10.1111/joor.12525] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2017] [Indexed: 11/28/2022]
Abstract
This study aimed to evaluate the possibility of root fenestration or oroantral communication by evaluating the distance from root apex to the sinus floor and buccal cortex in maxillary posterior teeth using cone-beam computed tomography (CBCT) images. The study included 2182 roots of the maxillary posterior teeth from 219 patients after reviewing CBCT images of 462 patients according to the location of roots by two endodontists. The distances from each root apex to the maxillary sinus floor and buccal and palatal cortices were evaluated according to sex and age, and the mean values were compared by one-way analysis of variance and Mann-Whitney U-test. The distance between root apex and maxillary sinus floor was the greatest in maxillary first premolars and shortest in the mesio-buccal roots of maxillary second molars. The distances from root apex to the buccal and palatal cortical bones were significantly greater in male patients than those in female patients (P < 0·05). The palatal roots of maxillary first molars exhibited the highest incidence as well as the greatest mean length (1·96 mm) of protrusion into the maxillary sinus. The distance from root apex to the sinus floor was found to increase with age, except in case of maxillary second premolars. Understanding the relationship of maxillary posterior teeth with the sinus floor and buccal cortex could provide clinicians valuable information to help reduce iatrogenic damage.
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Han YJ, Han DG, Chae JS, Park JH, Park BK, Kim HC, Choi KS. Theileria buffeli infections in grazing cattle in the Republic of Korea. Trop Biomed 2017; 34:263-269. [PMID: 33593006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Theileria infections are encountered worldwide, occasionally resulting in serious economic losses for the livestock industry. This study is an epidemiological survey of Theileria infections in Korean indigenous cattle populations in the Republic of Korea (ROK). Blood samples were collected from 100 cattle in April (n=50) (prior to pastureland grazing), and again four months later, in August (n=50) (half of the cattle put out for grazing and the other half kept in housing). All samples were tested for the presence of Theileria infection based on PCR amplification of the small subunit of ribosomal RNA gene. Twenty-two samples across the whole study were verified as positive for Theileria infection by PCR methods. In August, Theileria infection was markedly increased in grazing cattle (16/25 animals, 64%) compared with indoor cattle (4/25 animals, 16%); affected animals exhibited no clinical signs of infection. The red blood cell, hematocrit, and hemoglobin values were significantly lower in Theileriapositive cattle than in Theileria-negative cattle. Phylogenetic analysis demonstrated that the isolates from this study belonged to the T. buffeli species, and were significantly related to Types A, B, C, and E, and were distinct from T. buffeli Type D, which is known to be more pathogenic. These findings indicate that T. buffeli identified in Korean indigenous cattle have a low-to-mild pathogenicity. These results suggest that the T. buffeli infection is relatively higher in the ROK, and the infection rate may increase following grazing. Taken together, T. buffeli infection may not only be seasonally correlated, but also may be affected by management practices such as pastureland grazing.
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Kim HC, Huh S, Kim JY, Moon HR, Lee DN, Kim Y. Zn-MOFs containing flexible α,ω-alkane (or alkene)-dicarboxylates with 1,2-bis(4-pyridyl)ethylene: comparison with Zn-MOFs containing 1,2-bis(4-pyridyl)ethane ligands. CrystEngComm 2017. [DOI: 10.1039/c6ce02122k] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Lee YJ, Kwon MK, Lee SJ, Jeong SW, Kim HC, Oh TH, Lee SG. Influence of water on phase transition and rheological behavior of cellulose/ionic liquid/water ternary systems. J Appl Polym Sci 2016. [DOI: 10.1002/app.44658] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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