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Hydrogen storage is indeed fundamental to utilizing H 2 effectively, and porous carbon materials have emerged as highly promising supports for this purpose. γ-Graphyne (γGy) possesses abundant chemical bonds, considerable porosity, and exceptional chemical stability, positioning it as a promising candidate for hydrogen storage and transport applications. In this study, we conducted density functional theory calculations to investigate the potential of Li- and Na-loaded γGy as hydrogen storage materials. Our findings reveal that the hydrogen storage capacity (HSC) of Na-loaded γGy falls significantly short of expectations, whereas Li-loaded γGy demonstrates a notably higher HSC. Subsequently, our calculations indicate that B-doping of γGy does not promote favorable HSC, whereas N-doping exhibits a beneficial effect. Furthermore, we observed that tensile strain favors the hydrogen storage properties of 4Li@γGy and 4Li@N-γGy, while compressive strain enhances the hydrogen storage characteristics of 4Li@B-γGy. Notably, we discovered the capacity to adjust the valence band center of Li (ɛ VB), consequently influencing the hydrogen storage performance of γGy. Our investigation suggests that increased overlap between ɛ VB in Li-loaded graphyne and the effective alignment of H 2 and the supporting structure augments the binding force between Li and H 2 , thereby amplifying the HSC. [Display omitted] • Li-loaded γ-Graphyne stores H 2 via Valence-like interaction. • B- and N-doping can enhance storage capacity of Li-loaded γ-Graphyne. • Valence band center of Li tuned by strain achieve efficient adsorption-desorption. [ABSTRACT FROM AUTHOR]

Researchers interested in a paper's statement or aiming to acquire useful information from scientific papers rely heavily on references. Additionally, calculation accuracy is important for ensuring the technical soundness of scientific papers. However, inaccurate citations and calculations are common in scientific literature. A recently published paper in the Journal of Hazardous Materials reported a study on microplastics in groundwater and surface water from coastal south India (Tamil Nadu state) and the heavy metal adsorption capacities of different polymers. In this study, we identified critical calculation errors and incorrect reference citations. [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]

We provide a novel strategy to eliminate the epoxy group from the basal plane of graphene platelets. Given that the current reduction methods are unsatisfactory to clean the epoxides or sometimes cause undesirable structure deformations, the proposed strategy restores the original hexagonal carbon network without creating other new defects. To the best of our knowledge, the electric field mediated graphene oxide (GO) reduction has not yet been systematically investigated. The capability would permit the improvement of existing GO reduction methods and assist in the fabrication of high-quality graphitic materials. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Summary: Groundwater is nearly the sole source for freshwater supply on Jeju volcanic island because there are no perennial streams and rivers. Rain harvesting and subsequent artificial recharging have been conducted to meet growing freshwater demand in the island. We performed sequential samplings of harvested rainwater prior to the artificial injection in summer of 2008 at an artificial recharge site of western Jeju. Field measurements and chemical analyses of 313 rainwater samples revealed that there was a variation in chemical composition but the Na+K+SO4 +Cl type was dominant. Predominance of Na and Cl was likely to be from sea salts while substantial amount of SO4, NO3 , and NH4 is attributed to anthropogenic air pollution. The enrichment factors of SO4, HCO3, K, Mg, and Ca suggested that their non-marine contribution ranges from 75.4% to 99.98%. However, the sea salt contributed substantially to Cl concentration up to 73.5%. Most of the rainwater parameters generally decreased with time and they were generally stabilized after 20min, which is an effect of the first flush and thus some diversion (rerouting) is required for suitable artificial injection of the harvest rainwater in this study area. [ABSTRACT FROM AUTHOR]

Abstract: After TMI-2 accident, long-term core cooling management takes more importance rather than short-term management since probabilistic safety assessment performed revealed that long-term management had higher risk than the risk from short-term management. Regarding to this, since 1992, blockage of sump suction strainer was taken a place in Barseback Unit 2 (Sweden, BWR) and the United States Nuclear Regulatory Commission (USNRC) took into consideration as a General Safety Issue 191 (GSI-191), “PWR Sump Blockage,” in 1998 and opening an investigation. As a response to GSI-191 the Nuclear Energy Institute (NEI) submitted a recirculation sump evaluation methodology called NEI 04–07. In this methodology 0.75 was recommended for blow-down transport to lower containment based on the study on a boiling water reactor sump clogging issue and engineering judgment. USNRC quantitatively evaluated the blow-down transport in the safety evaluation report to NEI 04–07, and concluded the recommended blow-down transport fraction in NEI 04–07 was sufficiently conservative. However, the safety evaluation report to NEI 04–07 includes many values in evaluation steps which depend much on the containment configuration and engineering judgment. In particular the dependency on the plant type limits the generality of the USNRC’s conclusion on blow-down transport, when the considered plant is different from the volunteer plant. This study provides a modified evaluation method and results of debris blow-down transport for an Optimized Power Reactor 1000MWe (OPR1000) in Korea. The modified method includes more realistic physical background with less uncertainty while providing consistent result with NEI and USNRC methods. [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: In Korea, ground source heat pumps (GSHP) have been gaining popularity for space heating and cooling. Because there are few sources of high-temperature geothermal energy in the country, public baths (25–40°C) and geothermal heat pumps (∼15°C) using low-temperature groundwater or ground are the most dominant direct geothermal uses. The Promotion Law of the New and Renewable Energy Development, Use and Dissemination, enacted in 2004, imposed an obligatory installation of space heating and cooling systems using new and renewable energy sources including geothermal energy for newly constructed public buildings (more than 5% of total construction cost). Between 2004 and 2007, ground source heat pump systems occupied about 60% of the total public installation of new and renewable energy equipment. Starting with 35.2kW of two facilities in 2000, systems with the capacity of over 127.1MWt have been installed in 551 buildings (facilities) as of August 2008. The vertical closed heat pump system (closed loop) and the groundwater heat pump system (standing column well type; SCW) occupied 65.1% and 29.3%, respectively, among the total GSHP systems installed. The depth of the vertical loops ranged between 65 and 250m (average 159m) and the well depth of the SCW system ranged between 150 and 600m (average 391m). The number of geothermal energy companies, installing the GSHP systems, that are officially registered in the relevant authority increased from 5 in 2000 to 397 in July 2008. This paper presents details of the current status of ground source heat pumps in Korea. [Copyright &y& Elsevier]

Summary: The occurrence of submarine groundwater discharge (SGD) as well as its supply of many nutrients and metals to coastal seawaters is now generally known. However, previous studies have focused on the chemical and radiological analysis of groundwater, surface seawater, shallow marine sediments and their pore waters, as well as the measurement of upward flow through the marine sediments, as end members of the discharge process. In this study, chemical and isotopic analysis results of marine subsurface waters are reported. These were obtained from deep boreholes of an undersea liquefied petroleum gas (LPG) storage cavern, located about 8km off the western coast of Korea. The cavern is about 130–150m below the sea bottom, which is covered by a 4.8–19.5m silty clay stratum. An isotopic composition (δ2H and δ18O) of the marine subsurface waters falls on a mixing line between terrestrial groundwater and seawater. Vertical EC profiling at the cavern boreholes revealed the existence of a fresh water zone. An increase in the contents of ferrous iron and manganese and a decrease in levels of nitrate, bicarbonate and cavern seepage were recorded in August 2006, indicating a decreased submarine groundwater flux originating from land, mainly caused by an elevated cavern gas pressure. It is suggested in this study that the main source of fresh waters in the man-made undersea cavern is the submarine groundwater discharge mainly originating from the land. [Copyright &y& Elsevier]

Soil and groundwater at a rail rolling stock workshop in a metropolitan city were contaminated with heavy metals including Pb, Cu and Cd. Prior to remedial design, a variety of field and laboratory investigations were conducted to characterize hydrogeologic conditions and to examine levels and extents of the contamination. The hydrogeology of the studied site near the Han River is comprised of reclamation soil, alluvial deposit, weathered layer and soft rock. The alluvial deposit consists of sand, clay and silt, sandy gravel and its spatial distribution is very heterogeneous. Most groundwater occurs in the sandy gravel layer and groundwater within the site generally flows into two directions, north and west. Mean hydraulic gradients were 0.082-0.0129 and hydraulic conductivities of the main aquifer range between 5.42 × 10- 2 and 2.18 × 10- 6 cm/sec. Average linear velocity of groundwater was calculated as 15-24 m/year. The groundwater levels were mostly affected by atmospheric pressure change, which reflected confined characteristics of the aquifer system. High EC and low DO indicated anthropogenic contamination of the site. The Pb and Cu contamination of soil exceeding the Korean soil standards were mainly observed at locomotive inspection, rest train wash and scrap iron dump areas. Substantial contamination of groundwater with Cd was also detected at different location. [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]

Accurate quantum computational chemistry has evolved dramatically. The size of molecular systems, which can be studied accurately using molecular theory, is increasing very rapidly. Theoretical chemistry has opened up a world of new possibilities. It can treat real systems with predictable accuracy. Computational chemistry is becoming an integral part of theoretical and experimental research in chemical science. In this paper, we will review our recent developments in the theoretical and computational study on some very interesting subjects such as fluorescent fluoride sensor, "on–off" molecular switch, electron transport through π-stacking, and molecular electronic device on the basis of the molecular functional levels. We provide a brief introduction about the importance of all these systems in the present scenario of scientific activity and the numerical results and discussion in the light of experimentally found results. We have enjoyed good progress in each of the above areas. We are very excited about our discoveries in each field and would like to share this enthusiasm with readers. [ABSTRACT FROM AUTHOR]

Summary: Groundwater is being now seriously considered as heat sources for space heating and cooling in Korea. This study evaluated groundwater temperature data obtained from 266 Korean national groundwater monitoring stations. Spatial distribution of the groundwater temperatures is mainly affected by geographical latitude, air temperature, and local topographic elevations. The distribution pattern for the groundwater temperatures is most similar to that of the air temperature. Annual variations of the groundwater temperatures were classified into four main patterns. The P (periodic) type representing periodic annual variation was mainly found in shallow groundwaters (62.5%). Most peculiar is F (flat) type, in which the groundwater temperatures showed nearly no variation, and was mostly observed in deep wells (47.9%). Water levels are seemingly related to the classifications. Water levels of P or WP (weak periodic) types were shallowest while those of F type were deepest. Magnitude of annual temperature variation was within 8°C for 76.6% of the shallow wells while 97.1% account for the variation within 8°C in the deep wells. The highest groundwater temperatures mostly occurred in the coldest months (November–February) and the lowest temperatures in March–June, immediately before the hottest months (July–August). A simple exponential relationship between the amplitude and the phase difference with respect to the air temperature was found, which indicates propagation of the air temperature mainly due to conduction. Considering stability of groundwater temperatures, F type in bedrock aquifers appeared most suitable for the heat pumps in respect to efficient system design and maintenance. For practical application of the groundwater heat pumps, detailed investigation of hydrogeologic conditions and potential environmental changes is required. [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 gram-negative anaerobic oral bacterium Porphyromonas gingivalis initiates periodontal disease by binding to saliva-coated oral surfaces. To assess whether edible plants can synthesize biologically active P. gingivalis fimbrial antigen, for application as an oral vaccine, a cDNA fragment encoding the C-terminal binding portion of P. gingivalis fimbrial protein (FimA), was cloned into a plant expression vector immediately downstream of a cDNA fragment encoding the cholera toxin B subunit (CTB). The chimeric plasmid was transferred into potato (Solanum tuberosum) cells and the ctb–fimA cDNA fragment detected in transformed leaf genomic DNA by PCR amplification methods. A novel protein band of 21kDa was detected in transformed potato tuber extracts by immunoblot analysis. Oligomeric CTB–FimA (266–337) fusion protein was identified in the extracts through the binding of anti-CTX and anti-native fimbriae antibodies. The pentameric structure of CTB–FimA fusion protein was confirmed by ELISA measurements of GM1 ganglioside receptor binding. Quantification of the CTB–FimA fusion protein by ELISA indicated that the chimeric protein made up about 0.33% of total soluble tuber protein. The biosynthesis of immunologically detectable CTB–FimA fusion proteins and the assembly of fusion protein monomers into biologically active pentamers in transformed potato tuber tissues demonstrate the feasibility of synthesizing adjuvanted fimbrial protein in edible plants for development of adjuvanted mucosal vaccines against P. gingivalis generated periodontal disease. [Copyright &y& Elsevier]

Abstract: With the rising concerns regarding the time and space dependent hydrogen behavior in severe accidents, the calculation for local hydrogen combustion in compartment has been attempted using CFD codes like GOTHIC. In particular, the space resolved hydrogen combustion analysis is essential to address certain safety issues such as the safety components survivability, and to determine proper positions for hydrogen control devices as e.q. recombiners or igniters. In the GOTHIC 6.1b code, there are many advanced features associated with the hydrogen burn models to enhance its calculation capability. In this study, we performed premixed hydrogen/air combustion experiments with an upright, rectangular shaped, combustion chamber of dimensions 1m×0.024m×1m. The GOTHIC 6.1b code was used to simulate the hydrogen/air combustion experiments, and its prediction capability was assessed by comparing the experimental with multidimensional calculational results. Especially, the prediction capability of the GOTHIC 6.1b code for local hydrogen flame propagation phenomena was examined. For some cases, comparisons are also presented for lumped modeling of hydrogen combustion. By evaluating the effect of parametric simulations, we present some instructions for local hydrogen combustion analysis using the GOTHIC 6.1b code. From the analyses results, it is concluded that the modeling parameter of GOTHIC 6.1b code should be modified when applying the mechanistic burn model for hydrogen propagation analysis in small geometry. [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]

A DNA fragment encoding the cholera toxin A2 subunit (CTA2) linked to the enterotoxigenic Escherichia coli (ETEC) colony forming fimbrial antigen CFA/I was inserted into a plant expression vector containing the cholera toxin B subunit (CTB) fused to the rotavirus enterotoxin 22 amino acid epitope NSP422. Anti-CFA/I antibodies recognized a single band of approximately 72-kDa in transformed potato tuber tissue consistent with CFA/I–CTA2 and CTB–NSP4 fusion protein assembly into a cholera holotoxin-like structure. Enzyme-linked immunosorbent assay (GM1 ELISA) indicated that the CFA/I–CTA2 fusion protein bound specific GM1 ganglioside membrane receptors and made up approximately 0.002% of the total soluble tuber protein. Oral immunization of BALB/c mice with transformed tuber tissues generated anti-CFA/I serum and intestinal IgG and IgA secretory antibodies. Attachment of ETEC H10407 to enterocyte-like Caco-2 human colon carcinoma cells incubated with antiserum from immunized mice was reduced by 15% in comparison with Caco-2 cells incubated with serum from unimmunized mice. Immunogold staining of bacterial preparations revealed deposition of gold particles on E. coli H10407 fimbria incubated with immune serum but not on fimbria treated with sera from unimmunized mice demonstrating the specificity of antibodies in the immune serum for binding to CFA/I protein containing fimbria. The protection against toxic E. coli binding to Caco-2 cells generated by antisera from mice immunized with plant-synthesized CFA/I antigen demonstrates the feasibility of plant-based multi-component vaccine protection against enterotoxigenic E. coli, rotavirus and cholera, three enteric diseases that together exert the highest levels of child morbidity and mortality in economically emerging countries. [Copyright &y& Elsevier]

A set of lineament maps has been constructed, comprising a lineament distribution map, a lineament length density map, a lineament counts density map and a lineament cross-point density map. The ArcView SHP file is used as input format. Two Avenue™ script files (Remove-node and Generalize) have been developed, in which input errors can be minimized, to optimize the original digitized lineament map data. For analyzing the lineament characteristics, five Avenue™ script files (L-STAT, Dist-to-Line, Dist-to-Cross-point, L-Selection and PL-DENS) calculating the lineament statistics (lineament length density, counts density, cross-point density, distance between a well and the nearest lineament, and distance between a well and the nearest lineament cross-point) have been developed with Avenue™ language using ArcView 3.1 GIS software. It is very easy to calculate the lineament-related values with the above five script files. They are also useful for drawing lineament density maps and for revising and compiling existing lineament density maps with ArcView 3.1 GIS software. Lineament alignment or lineament density distribution can play an important role in groundwater exploration or productivity analysis. These script files, together with well data, can facilitate analysis of the relationship between groundwater characteristics and lineament distribution. [Copyright &y& Elsevier]

The hydrogen bond exchange reaction of cage water hexamer has been investigated. With an aid of transition path sampling method, a transition state for this reaction has been found. The transition state ensemble has been investigated as a function of energy, and the distribution of the structures of sampled transition states is consistent with that obtained by other method. From the ab initio calculations, it has been confirmed to be a transition state with one imaginary frequency along the reaction coordinate. The most important structural parameters for the transition are retardation (increase of ra and O⋯O distance) and C2 rotation of a water molecule. I obtained rate constants at temperatures ranging from 0 to 300 K considering quantum mechanical tunneling effect. At temperatures below 100 K, the tunneling effect is very important, while at high temperatures, the classical transition state theory approach gives reasonable data. Transition path sampling method is very useful to find transition states for many complicated chemical reactions in which we do not know about transition states or it is hard to find a transition state by quantum mechanical approaches. [Copyright &y& Elsevier]

The feasibility of soil vapor extraction and bioventing technologies was examined for a petroleum hydrocarbon-contaminated site. The test site was highly contaminated with toluene, ethylbenzene, and xylene, due to leakage from petroleum storage tanks. Three respiration tests demonstrated that the test site conditions were appropriate for application of air-based remediation technologies. The oxygen consumption rates ranged from 4.32 to 7.68 %-O 2 /day and biodegradation rates ranged from 2.72 to 4.84 mg/kg-day in respiration tests. In a 120-day soil vapor extraction pilot test, high initial mass removals (with tailing effects) were observed. As expected for the soil vapor extraction, the volatilization rate was much higher than the biodegradation rate. In a bioventing trial, the biodegradation effect was predominant, but a tailing effect was not observed. From this study, the suggested sequence of remediation is to construct an integrated system of soil vapor extraction and bioventing and initially operate the soil vapor extraction system until the volatilization rate becomes smaller than the biodegradation rate. After that, the system needs to be changed over to a bioventing mode. Field demonstration supports the feasibility of the proposed integrated system. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY) is a 2D carbon allotrope that has become increasingly prevalent among the family of carbon materials. GDY has advantages of high specific surface area and unique sp‐ and sp2‐hybridized carbon atom networks, is endowed with naturally adjustable bandgap, uniformly nanoporous structure, rapid carrier mobility activated by inhomogeneous π orbitals, and accessible on/off rations. These advantages, coupled with the direct binding ability of metal atoms resulting from sp‐hybridization, enable GDY to be applied across various research fields, especially as a substrate to support and further improve the performances of metals and metal compounds. Though many studies have considered the applications of GDY‐supported metals and metal compounds, a comprehensive introduction of synthesis and applications is deficient. Nonetheless, a discussion considering these diverse studies is essential to attract the attention of researchers and promote the development of new perspectives. In this review, a basic understanding of GDY and a thorough introduction to the synthesis and applications of GDY‐supported metals and metal compounds are presented. The review considers nanoparticles, nanoclusters, and dual and single atoms, and concurrently catalogues these in specific application domains. Moreover, future challenges and the development potentials of GDY‐supported materials are discussed to provide different perspectives and ideas. [ABSTRACT FROM AUTHOR]

Evaluates the effects of possible sources of uncertainty and inaccuracy that can arise in test performance and data analysis in pumping and slug tests. Slug and pumping as commonly used tests in obtaining hydraulic parameters of aquifers; Vulnerability to error and uncertainty of the slug test; Presence of head losses due to turbulence as characteristic of the pumping test.

The article presents a case study of 62-year-old Korean man who was diagnosed from pseudocyst in his auricle. A biopsy in the man's scaphoid fossa was done and yellowish clear fluid was observed. The man was treated with sodium tetradecyl sulfate (STS), which is known to cause endothelial destruction in various conditions. The lesion had almost disappeared in 4 weeks of treatment.

• Hyporheic zone depth is of importance for managing groundwater contamination. • We tested a probabilistic approach to delineate hyporheic zone depth. • This approach considered parameters as variables rather than fixed. • Our method is more accurate and less time-consuming than previous methods. Delineating the hyporheic zone, where groundwater and surface water mix, is of great importance for managing groundwater contamination introduced through surface water. A prior study proposed a method for estimating the hyporheic zone's depth using heat transfer analysis; this approach's high sensitivity compared with conventional tracer tests made it more appropriate for delineate the hyporheic zone depth. However, that method treated all related parameters as deterministic values, while real-world parameters are not fixed but vary widely around their means. In this study, we improved on this approach by converting it into a probabilistic method, in which the principal parameters in the governing equation were considered random values and were sampled using Monte-Carlo simulation. We conducted repeated heat transfer analyses for each case and collected the resulting hyporheic zone depths as probabilistic distributions. This allowed us to calculate the distribution of the hyporheic zone and its mean value more accurately and time-efficiently. [ABSTRACT FROM AUTHOR]

Aggregated amyloid β-peptide (Aβ) in small oligomeric forms inside the brain causes synaptic function disruption and the development of Alzheimer's disease (AD). Histidine is an important amino acid that may lead to structural changes. Aβ42 monomer chain includes 3 histidine residues that considering two ε and δ tautomers 8 isomers, including (εεε) and (εδδ) could be formed. Molecular dynamics simulation on homodimerization of (εεε) (the most common type of tautomers) and (εδδ) tautomers with different initial configurations using monomer chains from our previous work were performed to uncover the tautomeric behavior of histidine on Aβ42 aggregation in a physiological pH which is still largely unknown and impossible to observe experimentally. We found a higher propensity of forming β-sheet in (εδδ) homodimers and specifically in a greater amount from Aβ42 than from Aβ40. A smaller amount of β-sheet formation was observed for (εεε) homodimers compared with (εδδ). Additionally, interactions in (εδδ) homodimers may indicate the importance of the hydrophobic core and C-/N-terminals during oligomerization. Our findings indicate the important role of the tautomeric effect of histidine and (εδδ) homodimers at the early stage of Aβ aggregation. • (εδδ) tautomers show a high propensity to generate β-sheets during homodimerization. • (εδδ) homodimers may play an important role at the early stage of Aβ aggregation. • Histidine tautomerism can affect the structural properties of the amyloid peptides. [ABSTRACT FROM AUTHOR]

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]

Autism spectrum disorder is considered a vulnerability for many diseases including coronavirus disease 2019. This study investigated trends in coronavirus disease 2019 among children and adolescents with and without autism spectrum disorder and to evaluate whether there are differences in the prevalence, severity, and case fatality rate. We used data from the National Health Insurance Service for all people ⩽19 years of age. Among 9,187,211 children and adolescents ⩽19 years of age, 402,499 (4.4%) were coronavirus disease 2019–positive. Of the total population, 63,054 (0.7%) were diagnosed with autism spectrum disorder, among whom 2557 (4.1%) were coronavirus disease 2019–positive. The coronavirus disease 2019 prevalence was lower among children and adolescents with autism spectrum disorder, with 4055 per 100,000 versus 4383 per 100,000 without autism spectrum disorder (p < 0.001). However, children and adolescents with autism spectrum disorder exhibited a higher proportion of hospitalization (24.8% vs 21.5%) and severe disease (0.2% vs 0.01%) than those without autism spectrum disorder (p < 0.001); the length of hospital stay among inpatients was not different between the two groups (9.5 vs 9.4 days, respectively; p = 0.48). There were six deaths in total, with no deaths among children and adolescents with autism spectrum disorder. The quarantine policies have played a great role in sustaining low prevalence and higher hospitalization rates among children and adolescents with autism spectrum disorder. It is more difficult to prevent coronavirus disease 2019 in children and adolescents with autism spectrum disorder, as they have trouble communicating and adjusting to their new daily lives like wearing masks and social distancing. However, there have not been many studies that focused on coronavirus disease 2019 among children and adolescents with autism spectrum disorder. We included all Korean citizens under the age of 19 as our study subjects. Among them, we found out the prevalence, severity, and case fatality of coronavirus disease 2019 in children and adolescents with and without autism spectrum disorder. The prevalence of coronavirus disease 2019 among children and adolescents with autism spectrum disorder was lower than that of those without autism spectrum disorder. For severity, children and adolescents with autism spectrum disorder were more likely to enter severe stages of disease and had higher hospitalization rates than those without autism spectrum disorder. There were no deaths among children and adolescents with autism spectrum disorder, while a few died among children and adolescents without autism spectrum disorder. However, due to the small number of deaths, it was difficult to determine whether there was a link between autism spectrum disorder and coronavirus disease 2019 deaths. We found that the appropriate quarantine policies have played a great role in sustaining overall low prevalence and higher hospitalization rates among children and adolescents with autism spectrum disorder than those without autism spectrum disorder. Furthermore, because Korea has fewer schools and facilities (i.e. personal care, social training, and skilled nursing facility) for children and adolescents with autism spectrum disorder than other countries, those with autism spectrum disorder have fewer social contacts than even before the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

The water hexamer is known to have a number of isoenergetic structures. The first experimental identification of the O-H stretching vibrational spectra of the water hexamer was done in the presence of benzene. It was followed by the identification of the pure water hexamer structure by vibration-rotational tunneling (VRT) spectroscopy. Although both experiments seem to have located only the Cage structure, the structure of the benzene-water hexamer complex is not clearly known, and the effect of benzene in the water hexamer is unclear. In particular, it is not obvious how the energy difference between nearly isoenergetic water hexamer conformers changes in the presence of benzene. Thus, we have compared the benzene complexes with four low-lying isoenergetic water hexamers, Ring, Book, Cage, and Prism structures, using ab initio calculations. We also investigated the effects of the presence of benzene on the structures, harmonic vibrational frequencies, and infrared (IR) intensities for the four low-lying energy conformers. There is little change in the structure of the water hexamer upon its interaction with the benzene molecule. Hence the deformation energies are very small. The dominant contribution to the benzene-water cluster interaction mainly comes from the π-H interactions between benzene and a single water molecule. As a result of this π-H interaction, O-H[sub π] bond length increases and the corresponding stretching vibrational frequencies are redshifted. The IR spectral features of both (H[sub 2]O)[sub 6] and benzene-(H[sub 2]O)[sub 6] are quite similar. From both the energetics and the comparison of calculated and experimental spectra of the benzene-(H[sub 2]O)[sub 6], the water structure in these complexes is found to have the Cage form. In particular, among the four different Cage structures, only one conformer matches the experimental O-H vibrational frequencies. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The electronic and vibrational hyperpolarizabilities of polyenes NH[sub 2]-(HC==CH)[sub n]-NO[sub 2] and polyynes NH[sub 2]-(C=C)[sub n]-NO[sub 2] have been investigated. As the chain length increases, the first hyperpolarizabilities increase drastically for polyenes, while they increase moderately for polyynes. Furthermore, in polyenes the vibrational first hyperpolarizabilities are almost the same as the electronic first hyperpolarizabilities, while in polyynes the former is much smaller than the latter. An analysis of the electron densities of HOMOs of polyenes and polyynes confirms that the polyene π-frame is more efficient for long pathways of nonlinear optical molecules, while the polyyne π-frame is slightly better for very short pathways. In both polyenes and polyynes, the IR intensities arise mainly from the terminal carbon sites, while the Raman intensities, from the central carbon sites. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Aptamers are increasingly recognized as potent alternatives to antibodies for diagnostic and therapeutic applications. The application of deep learning, particularly attention-based models, for aptamer (DNA/RNA) sequences is an innovative field. The ongoing advancements in aptamer sequencing technologies coupled with machine learning algorithms have resulted in novel developments. Further research is required to investigate the full potential of deep learning models and address the challenges associated with the generation of sequences, like the large search space of possible sequences. In this study, we propose a workflow that integrates an attention mechanism within a framework of a generative variational autoencoder, to generate novel sequences by expanding latent memory. They show 100 % novelty compared with the dataset, and approximately 88 % of them show negative values for the minimum free energy, which may indicate the likelihood of an RNA sequence folding into a functional structure. Because the field of aptamer discovery is affected by data scarcity, advanced strategies that facilitate the generation of diverse and superior sequences are necessitated. The utilization of our workflow can result in novel aptamers. Thus, investigations such as the present study can address the abovementioned challenge. Our research is anticipated to facilitate further discoveries and advancements in aptamer fields. • We leverage attention-based variational autoencoders for the generation of novel aptamer sequences. • The application of deep learning, particularly attention-based models, for aptamers is an innovative and emerging field. • The field of aptamer (DNA/RNA) discovery is affected by data scarcity, so strategies for generation of diverse sequences are necessitated. [ABSTRACT FROM AUTHOR]

Aptamers are increasingly recognized as potent alternatives to antibodies for diagnostic and therapeutic applications. The application of deep learning, particularly attention-based models, for aptamer (DNA/RNA) sequences is an innovative field. The ongoing advancements in aptamer sequencing technologies coupled with machine learning algorithms have resulted in novel developments. Further research is required to investigate the full potential of deep learning models and address the challenges associated with the generation of sequences, like the large search space of possible sequences. In this study, we propose a workflow that integrates an attention mechanism within a framework of a generative variational autoencoder, to generate novel sequences by expanding latent memory. They show 100 % novelty compared with the dataset, and approximately 88 % of them show negative values for the minimum free energy, which may indicate the likelihood of an RNA sequence folding into a functional structure. Because the field of aptamer discovery is affected by data scarcity, advanced strategies that facilitate the generation of diverse and superior sequences are necessitated. The utilization of our workflow can result in novel aptamers. Thus, investigations such as the present study can address the abovementioned challenge. Our research is anticipated to facilitate further discoveries and advancements in aptamer fields. • We leverage attention-based variational autoencoders for the generation of novel aptamer sequences. • The application of deep learning, particularly attention-based models, for aptamers is an innovative and emerging field. • The field of aptamer (DNA/RNA) discovery is affected by data scarcity, so strategies for generation of diverse sequences are necessitated. [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]

Magnesium in biogenic aragonite skeletons is widely used to infer the geochemical conditions under which the minerals precipitated. However, because molecular speciation of Mg2+ in the aragonite crystal structure remains uncertain, questions are often posed about the reliability and utility of Mg as a paleoenvironment proxy. In this study, we investigated the Mg2+ coordination in abiogenic aragonite by applying first-principles density functional theory (DFT). We report for the first time a Mg2+-site disordered structure model of aragonite: substituted Mg2+ is five-fold coordinated and induces substantial disorder in the bond distances that depends on the relative positions of Mg2+ sites. Using the site disorder model, DFT qualitatively reproduces the key features of experimental Mg K -edge X-ray absorption near-edge structure (XANES) spectra of aragonite. DFT also resolves a long-standing conflict between experimental and theoretical studies pertaining to the enrichment of 26Mg in aragonite relative to calcite. The Boltzmann-averaged 26Mg/24Mg reduced partition function ratios were calculated in the order of aqueous Mg2+ > Mg-doped aragonite > Mg-doped calcite. The disorder structure model is likely applicable to the substitution of cations with radii smaller than the radius of Ca2+ ions in aragonite. Our study provides atomistic insight into metal substitution effects on the metal content and isotope fractionation in biogenic aragonite, which are critical for developing a reliable paleoenvironment proxy. [ABSTRACT FROM AUTHOR]

The skyrocketing single-plastic demand during the coronavirus disease 2019 (COVID-19) pandemic proved the limitation of top-down environmental policies in accomplishing sustainable consumption and waste management. Nevertheless, 'smart consumers' can make smart choices for sustainable development. However, a review of the South Korean environmental education curriculum reveals that the current structure heavily leans towards the elementary level and does not enlighten the public on 'what' and 'how' to live sustainably. This study uses a quick survey to suggest that the effectiveness of environmental education may be enhanced if: (1) guidance on how to live with the natural environment in harmony for collective cooperation towards resilient and sustainable community building is incorporated with a clear purpose, (2) environment-friendly culture-building activities are enforced to institutionalise a new paradigm of sustainability to replace today's consumerism, and (3) contents are updated regularly to include Earth and environmental science knowledge in the state of art. [ABSTRACT FROM AUTHOR]

Porphyromonas gingivalis induces destruction of periodontal tissues that surround and support the teeth, contributing to the development of periodontitis, which eventually results in tooth loss in adults. A 53-kDa protein of P. gingivalis is a major subunit variant protein of minor fimbriae (Mfa1), and is reported to be highly immunogenic and considered as a potential vaccine candidate. The gene encoding 53-kDa protein, was divided into three segments, and each DNA segment was fused to the gene coding for cholera toxin B subunit (CTB) to improve gut mucosal immune responses. The ctb-mfal fusion genes were expressed in the leaf tissues of Nicotiana benthamiana using agroinfiltration. Immunoblot analysis revealed that CTB-Mfa1 fusion proteins were produced in the agroinfiltrated leaves. The interaction of the plant-produced CTB-Mfa1 fusion proteins with GM1-ganglioside, which acts as the binding site for native CTB, was confirmed by GM1-ELISA. Mice immunized orally with the agroinfiltrated leaf powder containing the CTB-Mfa1 fusion proteins elicited serum IgG and fecal IgA antibodies to CTB and Mfa1. These results suggest that CTB-Mfa1 fusion proteins produced in plants can be used as an oral vaccine to control P. gingivalis infection-associated periodontitis. [ABSTRACT FROM AUTHOR]

Third order polarizability, (γ) taken from the collective electronic oscillator (CEO) method was used to calculate the two‐photon absorption (TPA) of tetrastyryl‐[2,2]paracyclophane derivatives with different through‐space charge transfer configurations considering various donor and acceptor combinations at the terminal styryl groups. For the virtually same linear absorption, different TPA spectra were obtained. For controlling and fine‐tuning frequency and cross‐sections of TPA the through‐space charge transfer interactions can be used. The results are explained by the electronic density matrices corresponding to governing oscillators in one‐ and two‐photon absorption and the ground state. It is indicated that for the studied systems mainly the lowest four oscillators are responsible for the TPA cross‐sections rather than a simple effective three‐state model. [ABSTRACT FROM AUTHOR]

We previously found that methylmercury induces expression of oncostatin M (OSM), which is released extracellularly and binds to tumor necrosis factor receptor 3 (TNFR3), possibly enhancing its own toxicity. However, the mechanism by which methylmercury causes OSM to bind to TNFR3 rather than to its known receptors, OSM receptor and LIFR, is unknown. In this study, we aimed to elucidate the effect of methylmercury modification of cysteine residues in OSM on binding to TNFR3. Immunostaining of TNFR3-V5-expressing cells suggested that methylmercury promoted binding of OSM to TNFR3 on the cell membrane. In an in vitro binding assay, OSM directly bound to the extracellular domain of TNFR3, and this binding was promoted by methylmercury. Additionally, the formation of a disulfide bond in the OSM molecule was essential for the binding of both proteins, and LC/MS analysis revealed that methylmercury directly modified the 105th cysteine residue (Cys105) in OSM. Next, mutant OSM, in which Cys105 was replaced by serine or methionine, increased the binding to TNFR3, and a similar effect was observed in immunoprecipitation using cultured cells. Furthermore, cell proliferation was inhibited by treatment with Cys105 mutant OSMs compared with wildtype OSM, and this effect was cancelled by TNFR3 knockdown. In conclusion, we revealed a novel mechanism of methylmercury toxicity, in which methylmercury directly modifies Cys105 in OSM, thereby inhibiting cell proliferation via promoting binding to TNFR3. This indicates a chemical disruption in the interaction between the ligand and the receptor is a part of methylmercury toxicity. [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]

Abstract A novel reduced graphene oxide/poly(1,5-dihydroxynaphthalene)/TiO 2 (RGO/PDHN/TiO 2) ternary nanocomposite conducting polymer is electrochemically synthesized on gold electrodes for supercapacitor applications. The RGO/PDHN/TiO 2 nanocomposite polymer film is characterized by field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectra (FT-IR), and energy dispersive X-ray spectrometry (EDX) and X-ray diffraction (XRD). The electrochemical performance of the nanocomposite polymer-modified electrode in 1.0 M HClO 4 is investigated by various electrochemical methods such as cyclic voltammetry (CV), galvanostatic charge-discharge, and electrochemical impedance spectroscopy (EIS). The RGO/PDHN/TiO 2 nanocomposite polymer film in a three-electrode system exhibits a large specific capacitance of 556 F g−1 in comparison with those obtained using RGO/PDHN (432 F g−1) and PDHN (223 F g−1) at a current density of 2.4 A g−1. Simultaneous usage of the electrical double layer capacitance (EDLC) of RGO with the pseudocapacitive behavior of PDHN and TiO 2 results in the large specific capacitance in RGO/PDHN/TiO 2. The electrochemical self-stabilities of RGO/PDHN/TiO 2 , RGO/PDHN, and PDHN polymer films are investigated by continuous cycling between −0.20–0.45 V. The RGO/PDHN/TiO 2 nanocomposite yields longer self-stability than that of other polymers after 1700 cycles and maintains about 74% of the initial capacitance values. [ABSTRACT FROM AUTHOR]

Abstract We previously reported significantly increased level of putrescine, a polyamine, in the brains of mice administered methylmercury. Moreover, addition of putrescine to culture medium reduced methylmercury toxicity in C17.2 mouse neural stem cells. In this study, the role of ornithine decarboxylase (ODC), an enzyme involved in putrescine synthesis, in response to methylmercury toxicity was investigated. Methylmercury increased ODC activity in mouse cerebrum and cerebellum, but this increase was hardly observed in the kidney and liver, where methylmercury accumulated at a high concentration. In the cerebrum and cerebellum, increased putrescine was observed with methylmercury administration. Methylmercury increased ODC activity in C17.2 cells, but this was almost completely abolished in the presence of an ODC inhibitor. Methylmercury also increased the level of ODC protein in mouse brain and C17.2 cells. In addition, C17.2 cells pretreated with ODC inhibitor showed higher methylmercury sensitivity than control cells. These results suggest that the increased ODC activity by methylmercury is involved in the increase in putrescine level, and ODC plays an important role in the reduction of methylmercury toxicity. This is the first study to provide evidence that increased ODC activity may be a protective response against methylmercury-induced neurotoxicity. Highlights • Methylmercury elevates ornithine decarboxylase (ODC) activity. • Methylmercury elevates ODC activity by increasing ODC protein. • Acceleration of putrescine synthesis by ODC reduces methylmercury toxicity. [ABSTRACT FROM AUTHOR]

Characterization of the conformational alterations involved in monomer misfolding is essential for elucidating the molecular basis of the initial stage of protein accumulation. Here, we report the first structural analyses of transthyretin (TTR) (26−57) fragments with two histidine tautomeric states (δ; N δ1 H and ε; N ε2 H) using replica-exchange molecular dynamics (REMD) simulations. Explaining the organizational properties and misfolding procedure is challenging because the δ and ε configurations can occur in the free neutral state. REMD revealed that β-sheet generation is favored for the δδ (16.8%) and εδ (6.7%) tautomeric isomers, showing frequent main-chain contacts between the stable regions near the head (N-terminus) and central (middle) part compared to the εε (4.8%) and δε (2.8%) isomers. The presence of smaller and wider local energy minima may be related to the structural stability and toxicity of δδ/εδ and εε/δε. Histidines31 and 56 were the parts of regular (such as β-strand) and nonregular (such as coil) secondary structures within the highly toxic TTR isomer. For TTR amyloidosis, focusing on hazardous isomeric forms with high sheet contents may be a potent treatment strategy. Overall, our findings support the tautomerism concept and aid in our comprehension of the basic tautomeric actions of neutral histidine throughout the misfolding process. [Display omitted] • Histidine tautomerism can influence the structural and misfolding properties of the monomeric TTR (26−57). • δδ and εδ tautomeric isomers are more likely to form β-sheets than εε and δε. • A potent therapeutic strategy for TTR amyloidosis may be to target toxic tautomeric states. • This study will help in developing effective therapeutic agents for the treatment of TTR-related amyloid diseases. [ABSTRACT FROM AUTHOR]