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Cadmium (Cd) is a toxic heavy metal that is widely present in the environment. Renal proximal tubule disorder is the main symptom of Cd chronic poisoning. Our previous study demonstrated that Cd inhibits the total activities of peroxisome proliferator-activated receptor (PPAR) transcription factors in human and rat proximal tubular cells. In this study, we investigated the involvement of PPAR in Cd renal toxicity using the HK-2 human proximal tubular cell line. Among PPAR isoform genes, only PPARD knockdown significantly showed resistance to Cd toxicity in HK-2 cells. The transcriptional activity of PPARδ was decreased not only by PPARD knockdown but also by Cd treatment. DNA microarray analysis showed that PPARD knockdown changed the expression of apoptosis-related genes in HK-2 cells. PPARD knockdown decreased apoptosis signals and caspase-3 activity induced by Cd treatment. PPARD knockdown did not affect the intracellular Cd level after Cd treatment. These results suggest that PPARδ plays a critical role in the modification of susceptibility to Cd renal toxicity and that the apoptosis pathway may be involved in PPARδ-related Cd toxicity. [ABSTRACT FROM AUTHOR]

Accessory minerals in granitic rocks are unlikely significant radionuclide contributions to groundwater due to their remarkable durability. However, accessory minerals incorporating U and Th may suffer structural damages due to the radioactivity and become highly susceptible to alteration. This study investigates geochemistry coupled with textural analysis of the U–Th bearing accessory minerals using a field emission scanning electron microscope and an electron probe micro-analyzer. Altered zircons with numerous open structures related to the radioactive decay show higher contents of U and Th and low analytical totals. Some thorites show high contents of U and non-formula elements due to the hydrothermal alteration in the metamicted thorite. The cerianite including U occurs as micro-veinlet in fracture with trace of Fe and Mn oxides, which indicates secondary phase formation from the decomposed accessory minerals in an oxidizing environment. Some accessory minerals with the high content of U and Th have been found in Mesozoic granite terrain in South Korea, where high concentration levels of radionuclide in groundwater were also reported. The leaching of U may be more likely when the accessory minerals are highly metamicted or altered as found in our samples. The altered zircon and thorite of the study area could be major carriers of radioelement in Mesozoic granitic aquifers where the occurrence of soluble U-minerals has not been reported. [Display omitted] • High radionuclides concentration in groundwater poses a threat to human health. • Accessary minerals can enrich groundwater with radionuclides in granite aquifers. • Altered zircons contain high U and Th levels with open structures. • Thorites show elevated U levels and non-formula elements due to alteration. • Metamicted and/or altered accessory minerals increase uranium leaching potential. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the optimal entomopathogenic fungus for the simultaneous control of the adults of two mosquito species, Aedes albopictus and Culex pipiens. The pathogenicity and virulence against the two species of mosquitoes were evaluated by using 30 isolates of Beauveria bassiana, an entomopathogenic fungus isolated from Korea that has high thermotolerance and UV-B tolerance. Regarding pathogenicity, 23 isolates were pathogenic to Ae. albopictus and 12 isolates were pathogenic to Cx. pipiens; Ae. albopictus adults were more susceptible to B. bassiana than Cx. pipiens adults. Among the isolates, 6 isolates that were simultaneously pathogenic to the two species of mosquitoes were used to evaluate virulence and conidia productivity. B. bassiana CN6T1W2 and JN5R1W1 had higher virulence than the other isolates, and they were more virulent in Ae. albopictus than inCx. pipiens. The conidia productivity of B. bassiana JN5R1W1 on millet grain medium was higher than that of B. bassiana CN6T1W2. Based on these results, B. bassiana JN5R1W1 was selected as the most efficient isolate for the simultaneous control of the two mosquito species. B. bassiana JN5R1W1 can be used effectively in the development of fungal insecticides to simultaneously control Ae. albopictus and Cx. pipiens adults with similar distribution areas. [ABSTRACT FROM AUTHOR]

Abstract Background Previous epidemiologic studies of the natural course of urticaria mainly focused on chronic spontaneous urticaria and were conducted at hospitals. The natural course of new-onset urticaria in the general population is unknown. Methods Patients with new-onset urticaria were identified from the National Health Insurance Service–National Sample Cohort data. Patients who had at least one visit for urticaria in 2002 and 2003 were excluded and the study cohort consisted of 1,027,620 subjects with no history of urticaria. We analyzed cumulative incidences of urticaria, chronic urticaria, and chronic urticaria remission using the life table estimation method from 2004 to 2013. Their association with related factors was analyzed using the Cox proportional hazards analysis. Results From 2004 to 2013, a total of 49,129 patients with new-onset urticaria were identified. The 10-year cumulative incidence rate of urticaria for the general population was 4.9% and that of chronic urticaria among patients with new-onset urticaria was 7.8%. Remission rates of chronic urticaria were 52.6% at 1 year and 88.9% at 5 years. Age, sex, residential area, and autoimmune thyroid disease were significantly associated with urticaria or chronic urticaria, but not with chronic urticaria remission, after adjusting for covariates. Female individuals were more likely to have new-onset urticaria but less likely to develop chronic urticaria compared with male individuals. Conclusions During the 10-year follow-up period, only a small proportion of patients with new-onset urticaria developed chronic urticaria. Remission was achieved in the majority of patients with chronic urticaria regardless of demographic characteristics or accompanying thyroid disease. [ABSTRACT FROM AUTHOR]

Abstract We performed DFT calculations to investigate the role of solvent of the non-aqueous electrolytes for the oxygen reduction reaction (ORR) kinetics in Li-air batteries. The calculated results on structural, thermodynamic and vibrational properties revealed that dimethyl sulfoxide (DMSO) is the most stable solvent among DME, DMSO, and MeCN of non-aqueous electrolytes. The LiCF 3 SO 3 /DMSO electrolyte was primarily assumed to be the most favorable for ORR kinetics from the IR analysis. We calculated thermodynamic properties of the ORR reactions held during the formation of superoxide (O 2 −) ion and the sole discharge products lithium peroxide (Li 2 O 2), and lithium oxide (Li 2 O) to study the ORR kinetics of the stable salt LiCF 3 SO 3 with three solvents namely dimethoxyethane (DME), dimethyl sulfoxide (DMSO), and acetonitrile (MeCN). The thermodynamic properties of the ORR reaction signified the best role of LiCF 3 SO 3 /DMSO electrolyte compared to LiCF 3 SO 3 /DME and LiCF 3 SO 3 /MeCN both in the gas and solution (water) phases. Highlights • The role of solvent of non-aqueous electrolyte in Li-air batteries was studied theoretically. • The LiCF 3 SO 3 /DMSO electrolyte was primarily assumed to be the most favorable for ORR kinetics from the IR analysis. • The thermodynamic properties of the ORR reactions including the (O 2 −) ion and Li 2 O 2 and Li 2 O • Improved ORR kinetics was due to the key role of LiCF 3 SO 3 /DMSO electrolyte compared to LiCF 3 SO 3 /DME and LiCF 3 SO 3 /MeCN. [ABSTRACT FROM AUTHOR]

At least 246 cases of coronavirus disease (COVID-19) have been linked to nightclubs in Seoul, South Korea. During the April 30-May 5 holiday, young adults from across the country who visited nightclubs in Seoul contracted COVID-19 and spread it nationally. Nightclubs were temporarily closed to limit COVID-19 spread. [ABSTRACT FROM AUTHOR]

The adsorption of sulfur dioxide (SO 2 ) on pristine and modified graphyne (including boron- or nitrogen- doping and introducing a single carbon atom defect) was investigated by density functional theory calculations. The structural, electronic, and magnetic properties of graphyne were changed according to the dopant atom site of doping and vacancy. SO 2 adsorption was obviously affected by modification of graphyne. SO 2 weakly interacted with pristine and nitrogen-doped graphynes. Boron doping at the sp-hybridized carbon site and introducing a single carbon atom vacancy in graphyne brought about a dramatic enhancement in SO 2 adsorption. The strongly chemisorbed SO 2 at these active sites caused deformation of the graphyne structure and electron redistribution, which induced changes in the conductivity and magnetism of graphynes. [ABSTRACT FROM AUTHOR]

Rubber nanocomposites based on carbon nanotubes (CNT), graphitic nanofiller (GR), and their hybrid (CNT+GR) were studied under static and cyclic strain for robotics applications. Room temperature vulcanized (RTV) silicone rubber was used as a matrix for the nanocomposites, which were prepared by solution mixing. The specimens based on CNT show a better modulus of 1.77 MPa than GR (0.71 MPa) and CNT+GR hybrid (0.85 MPa) specimens. The resistance was 0.27 kΩ (CNT) and 30.48 kΩ (CNT+GR hybrid) at 10% strain and increased to 0.35 kΩ and 46.49 kΩ at 100% strain. During cyclic strain (30%) tests, the CNT-based specimen shows larger hysteresis losses (slope m = -0.179) as dissipated heat than the GR (m = −0.032) and CNT+GR hybrid (m = -0.096) specimens. The specimens were tested as electrode materials in an actuator, and higher displacements of 1.992 mm (CNT), 1.489 mm (CNT+GR hybrid), and 0.075 mm (GR) were achieved at 10 kV (3 phr). Such improvements could be useful in intelligent objects as artificial muscles or electro-active locomotive parts. [ABSTRACT FROM AUTHOR]

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening diseases; however, it is hard to estimate their incidence due to the rarity of these diseases. We evaluated the incidence of SJS and TEN using a nationwide administrative database. Methods: We used a national medical insurance review system (Health Insurance Review and Assessment) database which contained the claim data of the entire nation from 2009 to 2013 to estimate the accurate incidence of SJS and TEN in Korea. The diagnostic codes of L511 (SJS) or L512 (TEN) from the International Classification of Diseases-10th revision were used to define the target study population. We also retrospectively followed up a 2011 SJS and TEN cohort for 24 months in order to assess the in-hospital mortality, related complications and total claims cost due to SJS and TEN. Results: A total of 1,167 (938 SJS and 229 TEN) cases were newly diagnosed from 2010 to 2013. The age- and sex-standardized annual incidences estimated in this study were 3.96 to 5.03 in SJS and 0.94 to 1.45 in TEN per million. There was no significant change in annual incidence throughout the study periods. When analyzed by 10-year age groups, the annual incidence was the lowest in group 20–29 years and the highest in group 70 for both SJS and TEN. Based on the 2011 cohort analysis, the in-hospital mortality were 5.7 and 15.1% for SJS and TEN, respectively. The mortality increased with age, particularly, after 40 years of age. Among the complications related with SJS or TEN, ocular sequelae was the most common (43.1 and 43.4% of SJS and TEN patients, respectively) followed by urethral sequelae (5.7 and 9.4% of SJS and TEN patients, respectively). Conclusion: Overall, our data suggest that SJS, and TEN are infrequent but constantly arise throughout the years. [ABSTRACT FROM AUTHOR]

This study aimed to identify the factors influencing South Korean voters’ attitudes towards increasing public expenditure on health and to identify whether the issue of healthcare expenditure influenced candidate choice in the 2012 Korean presidential election. The study used the data from a survey conducted by the Institute of Korean Politics at Seoul National University immediately following the 2012 presidential election. The survey was completed by a nationwide sample of 1,200 people aged 19 or over using a face-to-face interview method and proportional quota sampling based on sex, age, and region. About 44.3% of respondents had a positive attitude toward increasing public health expenditure. There was no significant difference by the candidate they supported (conservative Park Geun-hye or liberal Moon Jae-in). In particular, even 44.9% of conservative supporters agreed with more spending. Politically neutral respondents (OR = 1.76, 90% CI 1.22–2.54) and strong conservative party supporters (OR = 1.53, 90% CI 1.05–2.25) were more likely to support public health expenditure increase compared to strong liberal party supporters. Also, respondents who believed that the economic gap in the country was widening were 1.91 times more likely to support an increase in public health expenditures. However, the issue of health expenditure had no influence on voters’ choice of presidential candidates, and in particular no negative effect of choice of the ruling (conservative) party’s candidate. Our results should be interpreted with care; one possible reason for this lack of effect might be that constituents voted along partisan lines regardless of their attitude to the welfare issue; another possible explanation might be the success of the “left click strategy” of the conservative party. That is, the conservatives did not reject economic democratization or social welfare expansion. Further research should be done to explain why attitudes to health spending did not directly affect choice of candidate. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to identify private clinics that have a potential to perform the role of primary care providers (PCPs) in a primary care setting in Korea where private specialists are dominant. Methods: The 2013 National Patient Sample claim data of Health Insurance Review and Assessment Service in Korea was used. Two-step cluster analysis was performed using characteristics of private clinics, and patient and utilization characteristics of 27,797 private clinics. External validation of clusters was performed by assessing the association among clusters and outcomes of care provided by private clinics. Stability of clusters was cross-validated using discriminant analysis. Results: The result classified more than a half of private clinics into a potential PCP cluster. These were private clinics with specialties considered to be those of primary care physicians and were more likely to be located in non-metropolitan areas than specialized PCPs were. Compared to specialized PCPs, they had a higher percentage of pediatric and geriatric patients, patients with greater disease severity, a higher percentage of patients with complex comorbidities or with simple or minor disease groups, a higher number of patients and visits, and the same or higher quality of primary care. The most important factor in explaining variations between PCP clusters was the number of simple or minor disease groups per patient. Conclusion: This study identified potential PCPs and suggested the identifying criteria for PCPs. It will provide useful information for formulation of a primary care strengthening policy to policy makers in Korea as well as other countries with similar specialist-dominant primary care settings. [ABSTRACT FROM AUTHOR]

We previously reported that some of the substrate proteins recognized by Hrt3 or Ucc1, a component of Skp1/Cdc53/F-box protein ubiquitin ligase, may include proteins that are involved in the methylmercury toxicity and degraded by the proteasome. In this study, we found that Dld3 and Grs1 bound to Hrt3 and that Eno2 bound to Ucc1 using a yeast two-hybrid screening. We demonstrated that Dld3 and Grs1 are substrates that are ubiquitinated by Hrt3, and Eno2 is a substrate that is ubiquitinated by Ucc1. Moreover, any yeast showing overexpression of Dld3, Grs1, and Eno2 demonstrated higher methylmercury sensitivity. This indicates that Hrt3 and Ucc1 are involved in alleviating the methylmercury toxicity by promoting proteasomal degradation through the ubiquitination of Dld3, Grs1, and Eno2. [ABSTRACT FROM AUTHOR]

Research on soil microplastics is currently at an early stage, and there is no widely approved sampling protocol. Even so, any basic research should minimize errors to ensure that they are not amplified in future research. This paper examines some weaknesses of the original research paper 'Soil microplastic pollution under different land uses in tropics, southwestern China' recently published in this journal. The authors neglected to report the equipment used for soil sampling and did not use field blank samples. There is also a soil layer that was incorrectly named. The type and pore size of filter paper used for filtration during pre-analytical soil sample preparation is very important. In this paper the nature of the filter paper used, and its larger pore sizes are questionable by today's scientists. In addition, the authors in the original paper also overlooked reporting the statistical package used for statical analysis and ensuring if all data sets obey normality, homogeneity, and equality before running the one-way ANOVA test. This statistical step is widely considered mandatory, especially in the soil science community. So, this makes it difficult to trust the results documented. Furthermore, in the original paper, the needle and stereo microscope instruments used to sort microplastic-like materials prior to proper analysis are not reliable. [Display omitted] • A dissecting needle and stereo microscope shouldn't be used to sort out soil microplastics. • Gold-coated filter paper with smaller pore size is better than nitrocellulose filter paper. • The 0–10cm is the top soil layer and 10–20cm is the subsoil layer not a deep soil layer. • The statistical package used for analysis must be documented accordingly. • If the dataset is a normal distribution prior to ANOVA testing, it must be confirmed and reported. [ABSTRACT FROM AUTHOR]

We examined the alteration of gene expression in HK-2 human proximal tubular cells exposed to cadmium (Cd) using DNA microarray analysis. Cd increased the expression of 30 genes, including 7 genes coding for heat shock proteins, more than 2.0-fold and decreased the expression of 21 genes, including transcription-related genes, such as AP2B1, HOXA7, HOXA9 and TCEB2, less than 0.5-fold prior to the appearance of cytotoxicity in HK-2 cells. [ABSTRACT FROM AUTHOR]

Ube2d ubiquitin-conjugating enzymes promote p53 ubiquitination and proteasomal degradation. We previously showed that cadmium induced p53-dependent apoptosis through the suppression of expression of Ube2d family genes (Ube2d1, Ube2d2, Ube2d3 and Ube2d4) in normal rat proximal tubular cells. Here we examined the effects of inorganic arsenic and inorganic mercury, which induce apoptosis in proximal tubular cells, on cellular protein level of p53 and gene expression of Ube2d family. Inorganic arsenic induced apoptosis with p53 accumulation, and suppressed Ube2d1, Ube2d2 and Ube2d4 expression, but not Ube2d3. On the other hand, although apoptosis was induced in response to inorganic mercury in proximal tubular cells, protein level of p53 was not elevated by inorganic mercury. These results suggest that inorganic arsenic, but not inorganic mercury, may induce p53-dependent apoptotic pathways through downregulation of gene expression of Ube2d family in proximal tubular cells. [ABSTRACT FROM AUTHOR]

This paper discusses some critical weak points and mistakes identified in the original paper. The authors disregarded the importance of field blanks, sampling equipment, and well specifications for proper quality assurance and control. Beneficial field practices guarantee highly reliable results of laboratory analysis for microplastics. In addition, polymer type (chemical composition) and shape (form) are different classification criteria, but the authors mixed these in their description. The distribution and transport of microplastics should be properly understood, along with a knowledge of groundwater flow conditions, such as flow direction and velocity, in the study area. [ABSTRACT FROM AUTHOR]

Hesperetin (3′,5,7-trihydroxy-4-methoxyflavanone) is a metabolite of hesperidin (hesperetin-7-O-rutinoside), which belongs to the flavanone subgroup and is found mainly in citrus fruits. Hesperetin has been reported to be an effective osteoinductive compound in various in vivo and in vitro models. However, how hesperetin effects osteogenic differentiation is not fully understood. In this study, we investigated the capacity of hesperetin to stimulate the osteogenic differentiation of periodontal ligament stem cells (PDLSCs) and to relieve the anti-osteogenic effect of high glucose. Osteogenesis of PDLSCs was assessed by measurement of alkaline phosphatase (ALP) activity, and evaluation of the mRNA expression of ALP, runt-related gene 2 (Runx2), osterix (OSX), and FRA1 as osteogenic transcription factors, as well as assessment of protein expression of osteopontin (OPN) and collagen type IA (COLIA). When PDLSCs were exposed to a high concentration (30 mM) of glucose, osteogenic activity decreased compared to control cells. Hesperetin significantly increased ALP activity at doses of 1, 10, and 100 µM. Pretreatment of cells with hesperetin alleviated the high-glucose-induced suppression of the osteogenic activity of PDLSCs. Hesperetin scavenged intracellular reactive oxygen species (ROS) produced under high glucose condition. Furthermore, hesperetin increased the activity of the PI3K/Akt and β-catenin pathways. Consistent with this, blockage of Akt or β-catenin diminished the protective effect of hesperetin against high glucose-inhibited osteogenic differentiation. Collectively, our results suggest that hesperetin alleviates the high glucose-mediated suppression of osteogenic differentiation in PDLSCs by regulating ROS levels and the PI3K/Akt and β-catenin signaling pathways. [ABSTRACT FROM AUTHOR]

Abstract: Characteristics of hydrologic time series data obtained from an undersea LPG (butane and propane) storage cavern were analyzed in time and frequency domains. The analyzed data included cavern seepage rates, cavern operating pressures (gas pressures), water levels of monitoring boreholes in and around the cavern, surrounding tidal levels and site precipitations of long and short periods. The seepage rates showed annual periodic behaviors, which were related to seasonal LPG use pattern. The gas operating pressures were the most dominant controlling factor for the seepage rates. The tidal level revealed an apparent negative cross-correlation with the seepage rate. However, the long-term close correlation between the tidal level and the seepage rate might be attributed to coincident concurrence of the seasonal LPG use and the tidal level variation. The water levels of the monitoring boreholes showed significantly different auto-correlations and spectral densities with locations. The water levels near the butane cavern exhibited high memory effects and low cross-correlations with the tidal level while those of the propane cavern exhibited short memory effects and relatively higher cross-correlations with the tidal level. The difference in all the hydrologic responses (seepage and water level) of the two caverns to the outer stresses such as precipitation, gas operating pressure and tidal level, can be mostly related to the hydrogeologic stratification surrounding the caverns. The low permeable silty clay layer is very thick above the butane cavern while it is very thin about the propane, such that greater hydraulic connection to the overlying sea could be expected. [Copyright &y& Elsevier]

Based on water chemistry data, a rockfill dam in South Korea was investigated to identify major parts of substantial dam water leakage. Sinkholes in the dam crest and abnormal water leakage through the dam were observed since the first impounding of the dam. Previous investigations, including observational drillings, hydraulic tests, geophysical surveys, and tracer tests, revealed the development of a high permeability zone in the clay core and an abnormally high phreatic line zone in the left embankment. Sequential tracer tests provided further evidence of locations of preference and rapid water leakage pathways. In this study, we examined the usefulness of water chemistry data to confirm previous findings of water leakage. Factor analysis of the water chemistry data revealed major processes controlling the chemical composition, which include the wash-out and successive dissolution of fill materials in the dam interior, interaction between percolating water and dam core materials, and contamination of seeping water by grouting materials and previous tracer tests. Distinct spatial distribution of similar chemical groups was illustrated by cluster analysis and confirmed the location of major water leakage at the left abutment adjoining the spillway. [ABSTRACT FROM AUTHOR]

Abstract: The rockfill dam of this study has a clay core, filter zone, and sandy gravel shell, and it is located in the Nakdong River basin in Korea. Filling the reservoir began in August 1994 and it was full by April 1998. When the reservoir level was approximately 150 m, three settlement holes were found in the dam crest. To determine possible seepage paths and potential damaged areas within the rockfill dam, 15 tracer tests were performed during two periods. During the two test periods, six and nine tracer tests were conducted when the average water levels of the reservoir were 145 m and 142 m, respectively. Rhodamine WT (RWT) and bromide ion were used as tracers. For each test, 1800 to 4000 L of tracer solution were injected into the riprap for about 5 h. The 15 injection points were uniformly distributed from the right to left sides of the embankment and the two tracers were injected alternately. Tracer concentrations were monitored at 26 observation wells, which were divided into four groups by their geographical positions: right side of the crest, left side of the crest, right side of the dam toe, and left side of the dam toe. For each tracer test, more than 30 water samples were taken during a period of 96 h at each observation well. Based the breakthrough curves obtained from the sequential tracer tests, it was inferred that the most probable seepage paths and potential damaged area were in the left side of the crest (tongue wing zone) and, to a lesser extent, in the right side of the dam abutment. [Copyright &y& Elsevier]

Abstract: Feasibility of storing LNG in a lined rock cavern was evaluated using a pilot cryogenic rock cavern constructed in Daejeon, Korea. The pilot program included hydrogeological and engineering characterization of the rock mass around the cavern, design and construction of a drainage system, and pilot operation of the cryogenic cavern. An appropriate drainage system is most important to protect the containment system of LNG from thermal shocks due to ice lenses and hydrostatic pressure of groundwater. As a part of the pilot program, this study focused on the evaluation of hydraulic and engineering properties of the rock mass around the cavern. For this purpose, engineering logging of the rock cores, single and cross-hole hydraulic tests, and recharge/drainage tests were performed using seven drilled holes with different trends and plunges. Three main joint sets were found from the logging of the rock cores, acoustic borehole televiewer, and window mapping. The orientations of the three major joint sets were 60/209, 40/171, and 29/331, which can provide the main groundwater flow paths. Mean RQD values ranged from 56 to 88, which were classified as fair and good, although varying with depth along single boreholes. Hydraulic conductivity from the single and cross-hole hydraulic tests estimated in the order of 10−6 or 10− 7 m/s and corresponding transmissivity ranged between 10− 5 and 10− 6 m2/s. Permeable intervals identified from the hydraulic tests were mostly located above the cavern roof. Below the roof, the permeable zone was difficult to observe. According to the hydraulic communication tests performed for some designated intervals, hydraulic connection between boreholes was highly varied with depth or location, which indicated a very different distribution of water conducting joint sets along the boreholes. When water was injected at R1 with constant or varying flow rates, monotonous and stable seepage was observed at observation boreholes. From this, some stable drainage was expected even in relatively heavy rainfalls. When designing the drainage system of the cavern, the drainage holes should be orientated to maximize frequency of encountering the major joint sets and the permeable intervals identified from this study. [Copyright &y& Elsevier]

Abstract: The Unmun Dam, a rockfill dam with a clay core, filter zone, and sandy gravel shell, is located in the Nakdong river basin near Cheongdo-gun in Korea. In the dam area, the Cretaceous Gyeongsang supergroup andesite lies over intrusive granite. These form the intrusive contact near the main dam and cofferdam areas. The stratigraphic units in upward sequence consist of Cretaceous granite and andesite, weathered soft rock, and a soil layer of silty clay with gravel. The reservoir was first filled in August 1994 and was full by April 1998. Right after complete filling, three sinkholes were found in the dam crest near stations 2, 12, and 10 when the reservoir level was at around 150 m. The amount of leakage increased with rise of the reservoir level mainly caused by rainfall events. As a countermeasure for the abnormal leakage and dam rehabilitation, comprehensive surveys were performed on the dam including observational drillings, grouting, geophysical surveys, and tracer tests by Korea Water Resources Corporation (KOWACO). There were also further investigations for hydrologic characterization of the dam to identify water leakages. The groundwater levels at the 26 observation wells installed on the crest and dam toe were measured to evaluate the relationship between the reservoir level and groundwater level, and the influences on the dam leakage. Groundwater level at the left side of the embankment was high compared with a normal phreatic line; it was only 4 m lower than the reservoir level while 6.65 m lower than that at its right side. Fluctuation of the groundwater levels in the crest wells coincided well with the reservoir level without a significant lag time, which reflected a good hydraulic connection between the reservoir and the dam interior. Hydraulic conductivity estimated from 149 hydraulic tests at 9 monitoring wells constructed in the dam core showed a wide range between 1.42×10−4 and 4.35×10−8 cm/s with a geometric mean of 3.13×10−6 cm/s. Furthermore, water quality at the monitoring wells were much different from that of the reservoir. High levels of turbidity and electrical conductivity were observed at the monitoring wells in the left side of the bank. All these hydrologic characteristics reflected possible occurrence of the leakage on the dam, especially in the left embankment. This paper presents a summary of several investigation studies on the hydrologic characteristics of the rockfill dam, which implied abnormal water leakage. [Copyright &y& Elsevier]

We report the fabrication of semiconducting single-walled carbon nanotube (sc-SWNT) fibers via wet-spinning for electrochemical biosensor platforms. SWNTs were purified using thermal and acid treatments and separated into metallic SWNTs and sc-SWNTs. The sc-SWNTs were then wet-spun into flexible fibers. Then, an enzyme capable of reacting with glucose was immobilized on the sc-SWNT fibers to investigate the utility of sc-SWNT fibers as an electrochemical biosensor platform. The enzyme-activated sc-SWNT fibers, which exhibited the field effects, were then configured into fiber-type glucose sensors capable of detecting the glucose in a solution, demonstrating the potential of sc-SWNT fibers as an electrochemical biosensor platform. Unlabelled Image • SWNTs were purified/separated into metallic/semiconducting SWNTs, and then wet-spun into free-standing flexible fibers. • The fibers exhibited electrical conductivity of 70,700 S/cm and tensile strength of 279 MPa and interestingly, field effects. • This gate effect was demonstrated for a fiber-type glucose sensor with high sensitivity (0.5 μM). [ABSTRACT FROM AUTHOR]

The spatial synoptic classification (SSC) scheme is a daily weather-type classification scheme that is widely used in climatological and epidemiological investigations. We investigated the modification effect of temperature on respiratory disease-related hospital admissions (RAs) in children based on the SSC type. Data on RAs among children aged ≤ 19 years were collected from the National Inpatient Sample (NIS) database between 2011 and 2015 in Seoul, Korea. In this time-series study, we used Poisson generalized linear models allowing for over-dispersion, with stratification by season and each of the seven distinctive SSC types (Dry moderate [DM], Dry polar [DP], Dry tropical [DT], Moist moderate [MM], Moist polar [MP], Moist tropical [MT], and Transition [T]). We investigated the modification effects of temperature by SSC type through seasonal stratification, adjusting for other meteorological conditions, air pollution, and time trends, and considered the delayed effect for up to four consecutive days. We reported the relative risk percentage change with 95% confidence intervals (CIs) of RAs for every 1 °C increase in ambient temperature, by season and SSC type. Of the 8346 RAs overall investigated between 2011 and 2015, there were 5271 [63.2%] RAs in children aged 0–4 years. Overall, on majority of the days, the SSC types were DM (665 days [36.4%]), and DP (371 days [20.3%]). With regard to seasons, the different SSC types were distributed as follows: spring, DM (193 days [42.0%]); summer, MT (193 days [42.0%]); fall, DM (241 days [53.0%]); and winter, DP (228 days [50.6%]). A stronger association between RAs and temperature was observed overall (1.28% [95% CI; 0.04%, 2.53%]), and in spring (2.10% [0.62%, 3.60%]). According to SSC type, increased associations between RAs and temperature were detected with DM (2.20% [0.47%, 3.97%]) condition during spring and DT (2.41% [0.22%, 4.64%]) during fall. In addition, on re-categorizing the SSC types from a temperature or humidity standpoint, a modified association was observed especially in children aged ≤ 4 years and 5–9 years during spring. Using temperature variability to distinguish seasonal characteristics, we found that the relationship between temperature and RAs in children varied by SSC type. Application of the SSC scheme as an integrative approach may assist in gaining an understanding of seasonal characteristics and health effects due to temperature change. • The spatial synoptic classification (SSC) system is widely used in epidemiology. • We investigated the modification effect of temperature by SSC type. • The study focused on respiratory disease-related pediatric hospital admission (RA). • Temperature increases were associated with an increased RA rate. • The effect was modified by season, SSC type, and age. [ABSTRACT FROM AUTHOR]

B 4 C 12 achieves a rapid and stable CO 2 adsorption with a novel η3(O, C, O)-CO 2 configuration, and a small limiting potential for CO2RR producing HCOOH associating with suppressed HER. [Display omitted] The electrochemical reduction of CO 2 (CO2RR) to formic acid (HCOOH) is a promising approach to harness renewable energy for the production of value-added chemicals and contribute to carbon cycling. The search for cost-effective and efficient metal-free electrocatalysts is critical for realizing industrial applications. However, limited literature is available on this topic, primarily because the significant challenge of efficiently activating inert CO 2 remains unresolved. In this study, we have designed and applied a novel boron carbide (B 4 C 12) monolayered cage as an electrocatalyst for CO2RR to produce HCOOH. B 4 C 12 exhibits exceptional electronic, dynamic, and thermodynamic stability. Through comprehensive density functional theory computations, we have observed that B 4 C 12 rapidly and stably adsorbs CO 2 in a unique η3(O, C, O)-CO 2 configuration, resulting in excellent CO2RR activity with a low limiting potential (–0.38 V) and suppressed hydrogen evolution reaction. Our mechanistic investigations reveal that B 4 C 12 donates electrons to facilitate the bending of CO 2 , anchoring it onto the curved surface effectively. Additionally, the C atom in the η3(O, C, O)-CO 2 configuration attracts H+ + e− pairs through its active p electron, leading to the observed low limiting potential. This study not only successfully designs a novel class of metal-free electrocatalysts but also provides a promising strategy for advancing CO2RR research in the future. [ABSTRACT FROM AUTHOR]

This study evaluated temporal and spatial variability of groundwater and stream water fluxes using multiple temperature time series. The study area is located in Inbuk stream, Gangwon Province, Republic of Korea. Total annual precipitation was 698.5 mm in 2014 (1210.5 mm, over the last 30 years). For the study, temperature loggers were installed at depths of 0.1, 0.2, 0.3, 0.4, and 0.5 m at five points with at 10 m intervals (IST1, IST2, IST5, and IST6) in the streambed. Temperature data was continuously measured every two-hours from June 1 to November 30, 2014. Vertical fluid flow (seepage flux) were calculated using the VFLUX program, which uses temperature time series data measured at different depths by temperature loggers in the hyporheic zone. The results of flux calculations Inbuk stream show that vertical flux rates at four locations are generally upwelling condition in the dry season and downwelling condition in the wet season. This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2015R1A4A1041105). [ABSTRACT FROM AUTHOR]

The objective of this study is to examine groundwater responses before and after the November 15, 2017 Pohang earthquake (Mw=5.4) in a coastal area of Korea. The earthquake caused devastating damages to many buildings in the city. For this study, groundwater monitoring data (water level, electrical conductivity, water temperature) were obtained for January 2016 to February 2018 from the national groundwater monitoring stations, the rural groundwater monitoring wells, and the seawater intrusion monitoring wells and they are located within 25 km from the epicenter. There are eight national groundwater monitoring stations (PSG, PYI-D, PYI-S, PGB-D, PGB-S, PJH, PDH, PGR), five rural groundwater monitoring wells (PH1, PH2, PH3, PH4, PH5) and four seawater intrusion monitoring wells (GG1, GG2, YI1, YI2). Six of the monitored wells showed groundwater level decreases of 9–81 cm and two of them exhibited a recovery to the previous level within three days while the remaining wells did not. And six monitoring wells showed EC changes to the earthquake with -1,274–161 μS/cm. In addition, three wells showed discernible groundwater temperature fluctuations of -0.2–0.3oC. Here, we found the magnitude of groundwater level change is decreasing with distance of the monitoring wells from the epicenter. Some detailed analyses on the relationship between the responses and a variety of hydrogeological parameters deserve a further study. This work was supported by the Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry and Energy (No. 20183010111860) and by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2015R1A4A1041105). [ABSTRACT FROM AUTHOR]

Seasonal fluctuation in groundwater level (below the ground surface) and water quality variables are mainly attributed to climatic conditions, soil characteristic, drainage method, and management practices. Groundwater degradations and high nitrate values have taken considerable attention in the Republic of Korea. Water management practices needs to be based on results of monitoring of groundwater level and water quality variables. We studied spatial variations based on temporal fluctuations of groundwater level (GWL), and water quality parameters including pH, electrical conductivity (EC), and nitrate (NO3). These contents were monitored from year 2011 to 2014 in 70 groundwater wells of an agricultural region in Korea. The monitoring of contents was done in field and collected data after laboratory analysis, was analyzed by using geostatistical modeling and mapping techniques. Seasonal variations in GWL during the period of four years of monitoring were ranged 2.91–5.17 m and 2.80–4.08 m in wet and dry seasons, respectively. The variations in pH value for the same period ranged 6.55–7.50 and 6.69–7.82 in wet and dry seasons, respectively. The fluctuations in EC values ranged 125–604 μg/cm and 80–272 μg/cm in wet and dry seasons, respectively. The values for NO3 in groundwater ranged 12.87–34.40 mg/L and 9.46–38.80 mg/L during the wet and dry seasons. The GWL shows strong spatial dependence, while pH and EC show strong to weak spatial dependence. The groundwater NO3 shows partial spatial dependence with decreased values in 2014 compared to the values in 2011. This finding is attributed to improved agricultural practices and change in land use pattern from white radish and cabbage to orchards and ginseng fields. This work was supported by the National Research Foundation of Korea (NRF) grant, funded by the Korean government (MSIT) (NRF-2015R1A4A1041105) and Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2018R1D1A1B07047200). [ABSTRACT FROM AUTHOR]

Water is an essential element for all organism, including human. There are anaerobic organisms in nature, but no organisms hate water. As time goes on, the interest and need for such water management is increasing worldwide. Seawater is the most abundant on the Earth's water and accounts for more than 95% of the total. But this is the salty water that humans can not drink. So, even if most of the water is seawater, it is important to manage the fresh water that humans can drink. Uses in which water is used in human life are various such as agriculture and living water. Therefore, the purpose of this study is to contribute to the management of groundwater used in everyday life. Groundwater can be largely divided into quantity and water chemistry. Of these, interest in this study is related to water chemistry and is water temperature. Groundwater chemistry can be changed by temperature change. So, we want to predict changes in the future by analyzing past groundwater temperature changes. Box plot was used as the study method. This makes it is easy to see the yearly change visually. In this box, displays 25% to 75% of the total data distribution. Also, values outside the minimum (25% – 1.5 × IQR) and maximum (75% + 1.5 × IQR) range are designated and excluded as outliers. The line in the box represents the median, which is not necessarily located in the middle of the box. This study used water chemistry data from 2011 to 2015. The result of this study suggests that groundwater temperatures have risen over the past five years, and that this can increase in the future. This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2015R1A4A1041105). [ABSTRACT FROM AUTHOR]

Risk perception research, targeting the general public, necessitates the study of the multi-faceted aspects of perceived risk through a holistic approach. This study aimed to investigate the association between the two dimensions of risk perception of COVID-19, i.e., risk as a feeling and analysis, trust in the current government, political ideologies, and socio-demographic factors in South Korea. This study used a year-long repeated cross-sectional design, in which a national sample (n = 23,018) participated in 23 consecutive telephone surveys from February 2020 to February 2021. Most factors differed in the magnitude and direction of their relationships with the two dimensions of risk perception. However, trust in the current government, alone, delineated an association in the same direction for both dimensions, i.e., those with a lower level of trust exhibited higher levels of cognitive and affective risk perception. Although these results did not change significantly during the one-year observation period, they are related to the political interpretation of risk. This study revealed that affective and cognitive risk perceptions addressed different dimensions of risk perception. These findings could help governments and health authorities better understand the nature and mechanisms of public risk perception when implementing countermeasures and policies in response to the COVID-19 pandemic and other public health emergencies. [ABSTRACT FROM AUTHOR]

Microplastic (MPs) contamination in groundwater has received massive attention since plastic waste has been released directly into the environment. This study investigates MPs contamination in groundwater on the Jeju volcanic Island, Korea. To the best of our knowledge, this is the first study to identify MPs in groundwater from volcanic islands. A total of 21 sites were sampled for groundwater wells and springs in July and September (2021). Sampling was performed without cross-contamination through quality assurance and quality control. The results showed that MPs abundance ranged from 0.006 to 0.192 particles/L in groundwater samples. Additionally, MPs were detected in deep groundwater wells where the groundwater level was 143 m below ground surface. Eight MPs polymer types, including polypropylene, polyethylene, polyethylene terephthalate, polyvinyl chloride, polystyrene, polyamide, acrylonitrile butadiene styrene, and polyurethane, were detected using Micro-Fourier Transform Infrared Spectroscopy (μ-FT-IR). Most of the detected MPs size ranged from 20 to 100 μm, accounting for 95% of the total. Fragments and fiber shaped MPs were detected, with the majority of them being fragmented in groundwater samples. The concentrations of MPs and major ions in groundwater showed a positive correlation. A negative correlation was observed between MPs concentration and topographic elevation (r = −0.59, p = 0.01). The source of MPs contamination is most likely attributed to agricultural activities, such as plastic mulching and greenhouses, which account for most of the land use in the study area. In this study, MPs entered the aquifer through the soil at the surface and seeped through cracks in fractured rock on basalt with sealed groundwater wells. This study takes 500 L of samples to prevent sample bias, reveal plastic contamination in groundwater, and indicating the characteristics and sources of contaminated plastics. [Display omitted] • Most MPs detected in groundwater were smaller than 50 μm. • Eight polymers were identified, with PP and PE being dominant types in groundwater. • Predominant shapes of MPs in groundwater were fragments. • MPs abundance and groundwater levels have a negative correlation. [ABSTRACT FROM AUTHOR]

Polyaniline/gamma aluminum oxide (PAn/γ-Al 2 O 3 ) nanocomposites were synthesized via in situ electropolymerization on gold electrodes and modified electrodes (Au/PAn/γ-Al 2 O 3 ) were used for the detection of vitamin E (VE). The electrochemical and electropolymerization performance of aniline in the presence of γ-Al 2 O 3 nanoparticles improved dramatically. The kinetic results indicate that the polymerization growth rate of PAn in the presence of nanoparticles catalyst on Au electrode is fast. The resulting electrode exhibited excellent performance with regard to detecting VE. The mechanisms of electropolymerization of aniline in presence of γ-Al 2 O 3 nanoparticle catalyst and mechanism of redox behavior of VE are investigated. The limit of detection (LOD) was observed to be around 0.06 μM. The tolerance limits of some important interfering species with VE were studied. [ABSTRACT FROM AUTHOR]

Targeting the signaling pathway of the Vascular endothelial growth factor receptor-2 is a promising approach that has drawn attention in the quest to develop novel anti-cancer drugs and cardiovascular disease treatments. We construct a screening pipeline using machine learning classification integrated with similarity checks of approved drugs to find new inhibitors. The statistical metrics reveal that the random forest approach has slightly better performance. By further similarity screening against several approved drugs, two candidates are selected. Analysis of absorption, distribution, metabolism, excretion, and toxicity, along with molecular docking and dynamics are performed for the two candidates with regorafenib as a reference. The binding energies of molecule1, molecule2, and regorafenib are − 89.1, − 95.3, and − 87.4 (kJ/mol), respectively which suggest candidate compounds have strong binding to the target. Meanwhile, the median lethal dose and maximum tolerated dose for regorafenib, molecule1, and molecule2 are predicted to be 800, 1600, and 393 mg/kg, and 0.257, 0.527, and 0.428 log mg/kg/day, respectively. Also, the inhibitory activity of these compounds is predicted to be 7.23 and 7.31, which is comparable with the activity of pazopanib and sorafenib drugs. In light of these findings, the two compounds could be further investigated as potential candidates for anti-angiogenesis therapy. [ABSTRACT FROM AUTHOR]

The properties of vulcanizates based on graphitic nanofiller (GR) with flakes of medium surface area (150–450 m 2 /g) were studied for industrial applications. Room-temperature-vulcanized (RTV) silicone rubber was used as the matrix for preparing specimens. AFM micrographs reveal molecular level dispersion of GR with distributed particles in the range of 7–12 nm. The compressive load at 5 phr increased by ∼85% in the presence of a magnetic field. As the surface area of GR increases, the compressive modulus at 10 phr decreases by ∼35% and the actuation displacement at 15 phr increases by ∼340%. The transitional behavior in the mechanical properties was almost linear up to 300 m 2 /g and then fell sharply. The features of the vulcanizates are influenced by the nanoscale effect of the fillers, rapid stress-transfer from the polymer to the filler particles and consistent inter-particle connectivity in the rubber matrix. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are promising candidates for the replacement of lithium-ion batteries (LIBs) because of sodium's abundant reserves and the lower cost of sodium compared to lithium. This is a topic of interest for developing novel anodes with high storage capacity. Owing to their low cost, high stability, and conductivity, carbon-based materials have been studied extensively. However, sp2-C based carbon materials have low-rate capacities. Intensive density functional theory calculations have been implemented to explore the applicability of α, β, and γ graphyne nanotubes (αGyNTs, βGyNTs, and γGyNTs, respectively) as SIB anodes. Results suggest that (3, 0)-αGyNT, (2, 2)-βGyNT, and (4, 0)-γGyNT have, respectively, maximum Na storage capacities of 1535, 1302, and 1001 mAh/g, which exceeds the largest reported value of carbon materials (N-doped graphene foams with 852.6 mAh/g capacity). It was determined that αGyNTs have the largest storage capacity of the three types because they possess the largest specific surface area. Moreover, the larger pores of αGyNTs and βGyNTs allow easier diffusion and penetration of Na atoms compared to those of γGyNTs, which could result in better rate capacity. [ABSTRACT FROM AUTHOR]

Objectives To estimate the loss in quality-adjusted life-years (QALYs) in Korean adults due to 13 noncommunicable diseases (NCDs) in 2010 and predict changes in QALY loss through to the year 2040. Methods Thirteen NCDs (hypertension, diabetes mellitus, hyperlipidemia, stroke, myocardial infarction, angina, arthritis, osteoporosis, asthma, allergic rhinitis, atopic dermatitis, cataract, and depression) were selected from the Korean Community Health Survey 2010. The EuroQol five-dimensional questionnaire index from the Korean Community Health Survey 2010 and the Korean valuation set were used to estimate utility weights according to sex, age, and disease. Morbidity data were also obtained from the Korean Community Health Survey 2010. Mortality data according to disease and life expectancy were retrieved from the Korean Statistical Information Service. To predict future QALY loss, future population projection data from the Korean Statistical Information Service were used as substitutes for 2010 population size. Results Among the assessed 13 NCDs, the largest total QALY loss was for hypertension (513,113 QALYs; units are omitted hereafter), followed by arthritis (509,317) and stroke (431,049). The largest QALY loss due to mortality was stroke (306,733), whereas the largest QALY loss due to morbidity was arthritis (502,513). By applying the middle estimate of future population, the largest increase in total QALY loss between 2010 and 2040 was for hypertension (840,582), followed by stroke (719,076) and diabetes mellitus (474,607). Conclusions Hypertension, arthritis, and stroke are important in terms of total QALY loss, which will continuous to increase because of aging. These results could be used to develop cost-effective interventions that reduce the burden of NCDs. [ABSTRACT FROM AUTHOR]

Hundreds of millions of people around the world have been affected by Type 2 diabetes (T2D) which is a metabolic disorder. Clinical research has revealed T2D as a possible risk factor for Alzheimer's disease (AD) development (and vice versa). Amyloid-β (Aβ) and human islet amyloid polypeptide are the main pathological species in AD and T2D, respectively. However, the mechanisms by which these two amyloidogenic peptides co-aggregate are largely uninvestigated. Herein, for the first time, we present the cross-seeding between Amylin1-37 and Aβ40 considering the particular effect of the histidine tautomerism at atomic resolution applying the all-atom molecular dynamics (MD) simulations for heterodimeric complexes. The results via random seed MD simulations indicated that the Aβ40(δδδ) isomer in cross-talking with Islet(ε) and Islet(δ) isomers could retain or increase the β-sheet content in its structure that may make it more prone to further aggregation and exhibit higher toxicity. The other tautomeric isomers which initially did not have a β-sheet structure in their monomeric forms did not show any generated β-sheet, except for one seed of the Islet(ε) and Aβ40(εεε) heterodimers complex that displayed a small amount of formed β-sheet. This computational research may provide a different point of view to examine all possible parameters that may contribute to the development of AD and T2D and provide a better understanding of the pathological link between these two severe diseases. [ABSTRACT FROM AUTHOR]

The intramolecular magnetic couplingconstant (J) values of sets of diradicals linkedto bis-DTDA, OVER, and NN radicals(DTDA, OVER, and NN groups) through an aromatic coupler were studiedby unrestricted density functional theory calculations (UB3LYP/6-311++G(d,p)).Among 15 aromatic couplers, 9 compounds with an odd number of carbonatoms along its spin coupling path were found to interact ferromagneticallyupon coupling with bisradicals while the other 6 couplers with aneven number of carbon atoms along its spin coupling path give riseto antiferromagnetic coupling. The overall trends in the strengthof magnetic interactions of aromatic couplers were preserved for DTDA,OVER, and NN groups so that the trend can be utilized as an indexfor the magnetic strength of a given coupler. It was found that thedifferences in the nucleus-independent chemical shift (NICS), bondorder of connecting bonds, and Mulliken atomic spin density at connectedatoms between triplet and BS states are closely related to the intramolecularmagnetic behavior. 2,4- and 2,5-phosphole couplers exhibit the strongestintramolecular ferromagnetic and antiferromagnetic interactions among15 aromatic couplers when linked to diverse bisradicals. [ABSTRACT FROM AUTHOR]

We previously reported that methylmercury induces brain-specific upregulation of a chemokine gene, the CCL4 gene. In this study, we investigated the changes in gene expression levels of all chemokines in various tissues (cerebellum, cerebrum, kidney, liver, and spleen) of methylmercury-treated mice. We found that methylmercury induced upregulation of the CCL4 gene and the CCL3 gene, in a brain-specific manner. This finding suggests that upregulation of these two chemokine genes mediates selective damage by methylmercury in the central nervous system. [ABSTRACT FROM AUTHOR]

We report unique observations from drilling and hydraulic stimulation at a depth of approximately 4.3 km in two Enhanced Geothermal System (EGS) wells at the Pohang EGS site, South Korea. We surveyed drilling logs and hydraulic stimulation data, simulated pore pressure diffusion around the fault delineated by seismic and drilling log analyses, conducted acoustic image logging through the EGS wells, observed significant water level drops (740 m) in one of the two EGS wells, and obtained hydrochemical and isotopic variation data in conjunction with the microbial community characteristics of the two EGS wells. We discuss the hydraulic and hydrochemical responses of formation pore water to a few key seismic events near the hypocenter. We focused on how the geochemistry of water that flowed back from the geothermal wells changed in association with key seismic events. These were (1) a swarm of small earthquakes that occurred when a significant circulation mud loss occurred during well drilling, (2) the MW 3.2 earthquake during hydraulic stimulation, and (3) the MW 5.5 main shock two months after the end of hydraulic stimulation. This study highlights the value of real-time monitoring and water chemistry analysis, in addition to seismic monitoring during EGS operation. [ABSTRACT FROM AUTHOR]

Observation of novel linear relationship between Δ G OOH and Δ E H suggests Δ E H as a simple descriptor for rational design of HER/ORR bifunctional graphyne materials. [Display omitted] The high cost and relative scarcity of platinum (Pt) restrict large-scale commercialization of fuel cells, which has spurred researchers to develop low-cost alternatives integrating with high hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) catalytic activity. Herein, we performed density functional theory (DFT) calculations to explore the electrocatalytic activity of graphyne nanotubes (GyNTs). Several GyNTs were found to be potential metal-free electrocatalysts, with both HER and ORR activity superior to Pt. Moreover, we revealed a linear relationship between the Gibbs free energy change of O 2 adsorption (Δ G OOH) and binding energy of H adsorption (Δ E H), which could be attributed to the fact that both the C O bond of OOH adsorption and the C H bond of H adsorption are single bonds. Therefore, Δ E H is proposed as a general descriptor for the rational design of bifunctional graphyne materials toward HERs and ORRs. Our findings provide a simple strategy for the rational design of bifunctional materials. [ABSTRACT FROM AUTHOR]

Organic semiconductors to date having cofacial stacking motif are scarce compared to those having herringbone motif. Recently, Ahmed and co-workers have reported a series of novel n-type bisindenoanthrazolines (BIDAs) [Chem. Mater. 2010, 22, 5786], among which DADF and DADK adopt different slipped cofacial arrangements exhibiting distinct electron transport abilities. Here, we performed computational studies to understand the relationship between charge transport and molecular packing for these BIDAs molecules. This work focuses on the intrinsic molecular factors required for efficient and long-range charge transfer. Unlike the previous studies only focusing the charge injection barriers or the carrier mobilities, herein, we present the notion that lower electron injection barrier and higher intrinsic electron mobility should be both satisfied to achieve better n-type OFETs. We also note that the actual mobility can be significantly underestimated due to the limitation of the space-charge limited current method. Through computational modeling, we rationalized the superior electron conductivity of DADK and also shed light on the favorable or undesirable properties for efficient charge transport of BIDAs. Another key finding is that the intrinsic electron and hole mobilities are quite deviated from each other rather than comparable in current mobility calculations. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations were performed using a MPWB1K functional to interpret the charge transport (CT) properties of stacked annelated β-trithiophene molecules. The goal was to help understand how the chemical composition, face-to-face stacking, intra- and intermolecular correlations, and the applied electric field affect the CT properties of this organic semiconductor compared with those of the edge-to-face "herringbone" motif. The variations in the frontier molecular orbitals, energy gap, nonadiabatic electron attachment energies (EAE), and vertical detachment energies (VDE) were investigated under an external electric field as a function of the number of stacked layers (n). Two possible CT pathways, monomer-to-monomer (MM) and dimer-to-dimer (DD) transports, were postulated to determine the charge carrier conductivities of these molecules. The results highlight that the intermolecular electronic couplings and electrostatic interactions can significantly affect the stacking geometry, even in more extended structures; displaced stacks with smaller interlayer spacing resulted in more compact stacking and, thus, higher CT efficiency; face-to-face stacking geometries can help to reduce the energy gap and VDE. Despite the fact that common thiophene-based oligomers adopting edge-to-face herringbone motifs exhibited p-type (hole-transporting) characters, the face-to-face stacked models based on annelated β-trithiophenes exhibited remarkably increased n-type (electron-transporting) performances. The electric field in the z-direction produced a small influence on the DD charge transport, whereas both electron and hole mobilities decreased dramatically in the MM case. More importantly, in MM charge transport, the electric field increases the hole mobility so that it is higher than that of the electron. [ABSTRACT FROM AUTHOR]

Background: Healthcare quality assessment is being conducted in many countries. Although improving health equity is one of the major objectives of medical quality assessment, it is not clear whether different socio-economic statuses show the same health outcomes even in the same medical quality hospitals. No study has directly compared the health outcomes of different socio-economic statuses in the same hospitals nationwide.Objective: To determine whether the mortality rate of acute stroke patients differs according to socioeconomic status.Methods: This study was a retrospective, observational study of patients who were subject to acute stroke quality assessment in 2013. A total of 10 399 stroke cases were included in the study. When evaluating the mortality rate, the researchers analysed 10 228 cases, after excluding 171 cases that were measured twice for the same person. The levels of socio-economic status were divided according to the use of medical benefits, either National Health Insurance (NHI) for general population or Medical Aid (MA) for the vulnerable. The primary outcomes measured according to socio-economic status were in-hospital mortality rate and 1-year follow-up mortality rate of stroke patients. The secondary outcome was the composite performance score.Results: MA recipients had a higher in-hospital mortality rate (12.5 vs. 8.3%, P < 0.001) and 1-year follow-up mortality rate (14.9 vs. 10.8%, P < 0.001) than NHI subscribers. MA recipients had slightly lower scores than NHI subscribers (83.2 vs. 84.4, P = 0.02). In hospitals of the same grade, MA recipients had lower performance scores than NHI subscribers, although the difference was not statistically significant.Conclusions: There is a difference in mortality and healthcare performance according to socio-economic status in stroke patients in Korea. Efforts to improve equity are needed, including the development and monitoring of equality indicators and developing policies for healthcare equity. [ABSTRACT FROM AUTHOR]

Vanadium (V) and tungsten (W) are essential metals for various industries, but separating them is challenging due to the molecular similarity of the two metal ions. A highly concentrated mixed solution of V and W is obtained from spent selective catalytic reduction (SCR) catalysts, but their complete recycling is impeded by the difficulty of separating V and W. In this study, we investigate the ion exchange resin (IXR) technique's effectiveness for separating V and W from the leaching solution of spent catalysts. We evaluated the performance of three IXRs: Lewatit MP800 (strong basic), MP62WS (medium basic), and TP260 (weak acidic) for the separation of V and W ions in the solution. Among these IXRs, MP800 exhibits V and W ion separation behavior at pH 14. It selectively adsorbs W ions, while V ions demonstrate low affinity for adsorption on MP800. The primary mechanism for the adsorption of V and W ions appears to be an ion exchange reaction on the quaternary ammonium group of MP800. Conversely, MP62WS, which adsorbs V and W ions through both ion exchange and chelation mechanisms, does not separate V and W ions effectively when the solution's pH is controlled. The adsorbed W ions on MP800 can be completely regenerated with 2 M NaCl solution through re-ion exchange. We also conducted dynamic column operations using a simulated spent catalyst leaching solution (V = 600 mg/L, W = 4000 mg/L) with MP800 at pH 14. The successful separation of V and W was achieved for up to 15 bed volumes (BV). Finally, we performed V and W separation using an actual spent catalyst leaching solution. MP800 displayed a notably high separation factor (α V W) of 19.59, highlighting its effectiveness in separating V and W. [Display omitted] • The separation of vanadium(V) and tungsten(W) was investigated by ion exchange technique. • The W ion is selectively adsorbed onto Lewatit MP800 at pH 14 but V ion remains in leachate. • The adsorption of V or W ions on MP800 at pH 14 is based on an ion exchange mechanism. • V and W can be completely separated from each other in a continuous column operation. • In an actual SCR leachate, MP800(pH 14) demonstrates the feasibility of separating W. [ABSTRACT FROM AUTHOR]

We report a facile, but robust approach to fabricate structurally stable giant unilamellar vesicles (GUVs), on which a 1,2-dipalmitoyl- sn - glycero -3-phosphocholine (DPPC) bilayer membrane was made rigid by introducing amphiphilic block polymers. Particularly, we found that lateral co-assembly of an amphiphilic triblock copolymer (ATC) structured with a hydrophobic middle block and long molecular weight (20 K g/mol) hydrophilic end blocks remarkably enhanced the stretching modulus (k) of GUVs. When the membrane composition was optimized, the k value of ATC-hybridized GUVs increased to 6.2 × 108 Pa, which was approximately 10-fold higher than that of DPPC GUVs, thus leading to a much longer half-life. Moreover, we demonstrated that our ATC-hybridized GUVs enabled development of a fascinating vesicular model, which shows great potential as a structurally stable cell membrane mimic. [ABSTRACT FROM AUTHOR]

Microplastics (MP) and nanoplastics (NP) contamination of the terrestrial environment is a growing concern worldwide and is thought to impact soil biota, particularly the micro and mesofauna community, by various processes that may contribute to global change in terrestrial systems. Soils act as a long-term sink for MP, accumulating these contaminants and increasing their adverse impacts on soil ecosystems. Consequently, the whole terrestrial ecosystem is impacted by microplastic pollution, which also threatens human health by their potential transfer to the soil food web. In general, the ingestion of MP in different concentrations by soil micro and mesofauna can adversely affect their development and reproduction, impacting terrestrial ecosystems. MP in soil moves horizontally and vertically because of the movement of soil organisms and the disturbance caused by plants. However, the effects of MP on terrestrial micro-and mesofauna are largely overlooked. Here, we give the most recent information on the forgotten impacts of MP contamination of soil on microfauna and mesofauna communities (protists, tardigrades, soil rotifers, nematodes, collembola and mites). More than 50 studies focused on the impact of MP on these organisms between 1990 and 2022 have been reviewed. In general, plastic pollution does not directly affect the survival of organisms, except under co-contaminated plastics that can increase adverse effects (e.g. tire-tread particles on springtails). Besides, they can have adverse effects at oxidative stress and reduced reproduction (protists, nematodes, potworms, springtails or mites). It was observed that micro and mesofauna could act as passive plastic transporters, as shown for springtails or mites. Finally, this review discusses how soil micro- and mesofauna play a key role in facilitating the (bio-)degradation and movement of MP and NP through soil systems and, therefore, the potential transfer to soil depths. More research should be focused on plastic mixtures, community level and long-term experiments. [Display omitted] [ABSTRACT FROM AUTHOR]