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To delineate the glacial meltwater distribution, we used five noble gases for optimum multiparameter analysis (OMPA) of the water masses in the Dotson-Getz Trough (DGT), Amundsen Sea. The increased number of tracers allowed us to define potential source waters at the surface, which have not been possible with a small set of tracers. The highest submarine meltwater (SMW) fraction (~0.6%) was present at the depth of ~450 m near the Dotson Ice Shelf. The SMW appeared to travel beyond the continental shelf break along an isopycnal layer. Air-equilibrated freshwater (up to 1.5%), presumably ventilated SMW (VMW) and surface melts, was present in the surface layer (-1 for the adjacent ice shelves, assuming that the SMW fractions represent accumulation since the previous Winter Water formation. The Meteoric Water (MET) fractions, consisting of SMW and VMW, comprised 24% of those derived from oxygen isotopes, indicating that the annual input from basal melting is far less than the inventory of meteoric water, represented by MET.

Methane (CH4) is one of the most important greenhouse gases on Earth. Recent finding of the strong CH4 emissions in the Arctic Seas with shrinking the sea ice may amplify the Arctic warming leading to the positive feedback in the Arctic climate. Korea Polar Research Institute (KOPRI) has ongoing interest in Arctic environmental conditions including the potential release of the CH4 from the seabed to the water column and finally, further to the atmosphere. During the last 13 years throughout a series of campaigns on the Korean ice-breaker, R/V Araon, we measured CH4 concentrations at the surface ocean and overlying air in summer season to estimate the emissions from the western arctic seas including the Chukchi Sea, the Beaufort Sea, and the East Siberian Sea. We compare each of these seas and the Central Arctic Ocean covering the deep Arctic Ocean basin. The surface ocean showed super-saturation almost everywhere with respect to the CH4 in the overlying air. Nonetheless, we have insufficient regional coverage to assess any possible saturation anomaly trend in each sea. Flux densities of outgassing CH4 are modestly larger than the global mean value of the continental shelf except for the Central Arctic Ocean where the CH4 emission is slightly lower. Our estimate of CH4 emission in the East Siberian Sea is far larger than other Arctic Seas abiding by the previous observations, but its magnitude is far lower due likely to the distance from the hot spot area. Future methane flux studies should be extended to shallow, nearshore environments where rate of permafrost degradation should be greatest in response to ongoing marine transgression.

This study aims to identify the effect of the occupant density, application of the evacuation delay time, and the degree of opening of the fire doors in the household, parameters that are used in the performance-based design of the officetels of a residential structure, on the evaluation of evacuation safety and to suggest realistic alternatives. To this end, a preliminary survey was conducted on the number and ratio of residential officetels among the performance-based design targets in Gwangju Metropolitan City, which were implemented up to December 2020. Following this, two representative examples were selected, and for each type, an occupant density of 9.3 m2/person and 18.6 m2/person and an evacuation delay time of W1 and W2 were applied. In addition, for the degree of opening of the fire doors, full opening, 1/4 opening, and leakage gap were applied. With these conditions, the evaluation of evacuation safety was performed for 32 cases. Results of the evaluation showed that evacuation safety was secured in all cases for an occupant density of 18.6 m2/person, an evacuation delay time of W2, and the application of a leakage gap to the opening of the fire door. Therefore, using the above mentioned three parameters for the performance-based design of officetels of residential structures, we have proposed a more realistic design method in this study.

Common buckwheat sprout (CBS) contains more flavone C-glycosides (FCGs) and flavonol O-glycosides (FOGs) than does common buckwheat seed. Both flavonoids in CBS are well known for providing benefits to human health. However, they are relatively less bioaccessible and more directly degradable to aglycone during digestion than are multiglycosylated flavonoids. To overcome such limitations, the water solubility and digestion stability of FCGs and FOGs were enhanced by transglycosylation using cyclodextrin glycosyltransferase. Gastric conditions had little effect on the stability of FCGs and FOGs and their enzyme-modified compounds. In contrast, under intestinal conditions, transglycosylated FCGs lost a glucose moiety and reverted to their parent compounds before transglycosylation. Under colonic fermentation using human fecal samples, the different profiles and concentrations of short-chain fatty acids were suggested to be mainly due to the presence of transglycosylated FCGs and FOGs. These findings indicate that the process of transglycosylation changes the bioaccessibility of flavonoids in CBS.

Objectives Coronavirus Disease-19 (COVID-19) is a respiratory infection characterized by the main symptoms of pneumonia and fever. It is caused by the novel coronavirus severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), which is known to spread via respiratory droplets. We aimed to determine the rate and likelihood of SARS-CoV-2 transmission from COVID-19 patients through non-respiratory routes. Methods Serum, urine, and stool samples were collected from 74 hospitalized patients diagnosed with COVID-19 based on the detection of SARS-CoV-2 in respiratory samples. The SARS-CoV-2 RNA genome was extracted from each specimen and real-time reverse transcription polymerase chain reaction performed. CaCo-2 cells were inoculated with the specimens containing the SARS-COV-2 genome, and subcultured for virus isolation. After culturing, viral replication in the cell supernatant was assessed. Results Of the samples collected from 74 COVID-19 patients, SARS-CoV-2 was detected in 15 serum, urine, or stool samples. The virus detection rate in the serum, urine, and stool samples were 2.8% (9/323), 0.8% (2/247), and 10.1% (13/129), and the mean viral load was 1,210 ± 1,861, 79 ± 30, and 3,176 ± 7,208 copy/μL, respectively. However, the SARS-CoV-2 was not isolated by the culture method from the samples that tested positive for the SARS-CoV-2 gene. Conclusion While the virus remained detectable in the respiratory samples of COVID-19 patients for several days after hospitalization, its detection in the serum, urine, and stool samples was intermittent. Since the virus could not be isolated from the SARS-COV-2-positive samples, the risk of viral transmission via stool and urine is expected to be low.

In this paper, the application of evacuation delay time (Cognition time + initiation time) and examine the degree of opening of fire doors in households for evaluating evacuation safety and suggest a realistic alternative. In order to proceed with this study, first of all, the preliminary investigation on evacuation safety evacuation of residential-type buildings (Apartment, urban living houses, etc.) among the performance-oriented design targets of Gwangju Metropolitan City, which was implemented until June 2018. Then, for the two representative types that are commonly used among the previously surveyed buildings, evacuation delay time is applied to W1, W2, and respectively simulating the opening of the doors is applied to th full open, 1/4 open, the leakage gap and evacuation safety evaluation was performed. As a result of evaluating evacuation safety was found that it is difficult to secure evacuation safety regardless of evacuation delay time W1 and W2 when the fire door is fully open and 1/4 open, Only when the leakage gap is applied evacuation safety was ensured even if evacuation delay time W2 was applied. Therefore, when a residential building is subject to performance-oriented design, evaluating the application of W2 rather than W1 is considered for evacuation delay time to reflect concern about privacy infringement due to CCTV installation, etc. In order to secure the Smoke blocking performance of the fire door and to improve the performance-oriented design, I would like to propose to consider the method of applying a leak gap to the degree of opening of the fire door. Through this, it is expected that the performance-oriented design will be a step further by performing evacuation safety evaluation with more realistic data.

OBJECTIVES: Following reports of patients with unexplained pneumonia at the end of December 2019 in Wuhan, China, the causative agent was identified as coronavirus (SARS-CoV-2), and the 2019 novel coronavirus disease was named COVID-19 by the World Health Organization. Putative patients with COVID-19 have been identified in South Korea, and attempts have been made to isolate the pathogen from these patients. METHODS: Upper and lower respiratory tract secretion samples from putative patients with COVID-19 were inoculated onto cells to isolate the virus. Full genome sequencing and electron microscopy were used to identify the virus. RESULTS: The virus replicated in Vero cells and cytopathic effects were observed. Full genome sequencing showed that the virus genome exhibited sequence homology of more than 99.9% with SARS-CoV-2 which was isolated from patients from other countries, for instance China. Sequence homology of SARS-CoV-2 with SARS-CoV, and MERS-CoV was 77.5% and 50%, respectively. Coronavirus-specific morphology was observed by electron microscopy in virus-infected Vero cells. CONCLUSION: SARS-CoV-2 was isolated from putative patients with unexplained pneumonia and intermittent coughing and fever. The isolated virus was named BetaCoV/Korea/KCDC03/2020.

We evaluated genetic variation in Middle East respiratory syndrome coronavirus (MERS-CoV) imported to South Korea in 2018 using specimens from a patient and isolates from infected Caco-2 cells. The MERS-CoV strain in this study was genetically similar to a strain isolated in Riyadh, Saudi Arabia, in 2017.

Soy isoflavones (SIs) show various health benefits, such as antioxidant and estrogenic effects. It is important to understand bioaccessibility and bioavailability of SIs due to their close relationship with their bioactivities. In this study, antioxidant capacity, bioaccessibility, and bioavailability of twelve SIs were evaluated using radical-scavenging methods, a simulation of the human digestion, and Caco-2 cell in Transwell, respectively. All SIs were stable (91.1–99.2%) under gastric digestion compared with the control (100%), whereas acetyl and malonyl conjugates were unstable (38.5% and 65.5%, respectively) under small intestinal digestion. SI aglycones showed higher permeation (7–15 times) and cell accumulation (8.8 times) than their glucosides. A small amount of SI conjugates was found in their intact forms in the cell and in the basolateral side of the Transwell. These results suggest that SI conjugates, especially malonyl and acetyl forms, have incidental bioactivity after being metabolized to aglycones inside the cell.

Prolintane (1-Phenyl-2-pyrrolidinylpentane), a synthetic central nervous system (CNS) stimulant, is structurally similar to amphetamine but pharmacologically acts as a dopamine reuptake inhibitor like cocaine. While several case studies reported adverse effects and recreational use of prolintane, the abuse potential of the drug has not been systemically examined yet. In the present study, we evaluated the behavioral effects of prolintane regarding its abuse liability in rodents using locomotor activity, conditioned place preference (CPP), self-administration (SA), and drug discrimination paradigms, as well as in-vivo microdialysis experiment. First, acute prolintane (10 and 20 mg/kg, intraperitoneal injection) increased locomotor activity (distance traveled, cm) in mice but to a lesser degree than methamphetamine (as a positive control). We also found that a single and solitary injection of prolintane (20 mg/kg, IP) significantly increased extracellular dopamine in the striatum. The following result suggests that its stimulatory effects might be associated with the mesolimbic dopaminergic pathway. Further, prolintane produced a significant drug-paired place preference at doses of both 10 and 20 mg/kg. In the SA experiment, the mice that self-administered prolintane intravenously (4 mg/kg/inf) showed a higher infusion and active lever responses but not inactive lever responses. Additionally, cumulative doses of prolintane partially elicited cocaine-appropriate lever responses (38.57% at doses up to 10 mg/kg) in rats. These results implied that prolintane has not only rewarding and reinforcing effects but also interoceptive stimulus properties, which are similar to cocaine at a moderate level. Taken together, this study was the first to show, to our knowledge, that prolintane has a certain level of abuse potential and should be considered carefully as a valuable basis for legal restrictions on use.

Previous reports on phytochemicals in green tea (GT) and processed teas mainly focused on more representative compounds such as catechins. Here, we focus on the insignificantly studied non-catechin components in tea extracts, and explore the multivariate correlation between diverse phenolic compounds in tea and the in vitro antioxidant and anticancer effects. Extracts from GT and four types of processed teas were further divided into hydrophilic and hydrophobic fractions, whose phenolic compositions and antioxidant capacities were quantified using HPLC-MS and three antioxidant assays, respectively. For three types of teas, the anticancer effects of their extracts and fractions were assessed using cancer cell lines. The hydrophobic fractions had lower antioxidant capacities than the corresponding hydrophilic fractions, but exhibited superior antiproliferative effects on cancer cells compared with the whole extract and the hydrophilic fraction. Partial least squares-discriminant analysis revealed a strong correlation between the anticancer effects and the theaflavins and flavonols. Therefore, in addition to catechins, the hydrophobic fraction of tea extracts may have beneficial health effects.

Invasive bioelectrodes are widely used as an effective treatment for several acute and chronic diseases. In earlier work using high surface area invasive porous bioelectrodes evaluated in an animal model of alcoholism withdrawal, we demonstrated significantly improved electrophysiological and behavioral responses. In this study, we further modify the surface of these invasive porous bioelectrodes with noble metal (Ag, Au, Pt) nanoparticles. Compared to both conventional and porous bioelectrodes, noble metal sensitized invasive porous bioelectrodes show markedly increased low threshold (LT) and wide dynamic range (WDR) neuronal activity. In particular, Pt-sensitized invasive porous bioelectrodes show the highest WDR neuronal activity only upon insertion. In addition, Ag-sensitized invasive porous bioelectrodes, whose surface area is about 37 times greater than that of conventional bioelectrodes, show improved electrochemical properties with higher LT and WDR neuronal activity when stimulated. In an animal model of chronic alcoholism, using normal and alcohol-treated Sprague-Dawley (SD) rats evaluated with the elevated plus maze (EPM) test, the Ag-sensitized invasive porous bioelectrodes show about 20% higher open arms time. These results suggest that these noble metal-sensitized invasive bioelectrodes may offer improved therapeutic outcomes for the treatment of chronic alcoholism, and given these enhanced electrophysiological properties, for other conditions as well.

Biological concentrations of methylmercury (MeHg) are elevated throughout the Arctic Ocean; however, to date, the major sources and the spatial variability of MeHg are not well quantified. To identify the major inputs and outputs of MeHg to the Arctic shelf water column, we measured MeHg concentrations in the seawater and sediment samples from the East Siberian Sea collected from August to September 2018. We found that the MeHg concentrations in seawater and pore water were higher on the slope than on the shelf, while the MeHg concentrations in the sediment were higher on the shelf than on the slope. We created a mass budget for MeHg and found that the benthic diffusion and resuspension largely exceed other sources, such as atmospheric deposition and river water input. The major sinks of MeHg in the water column were dark demethylation and evasion. When we extrapolated our findings on benthic diffusion to the entire Arctic shelf system, the annual MeHg diffusion from the shelf sediments was estimated to be 23,065 ± 939 mol yr-1, about 2 times higher than previously proposed river discharges. Our study suggests that the MeHg input from shelf sediments in the Arctic Ocean is significant and has been previously underestimated.

Background: The emergence of influenza viruses resistant to anti-influenza drugs is a threat to public health. The Korea Centers for Disease Control and Prevention operates the Korea Influenza and Respiratory Viruses Surveillance System (KINRESS) to monitor epidemic of influenza and Severe Acute Respiratory Infection (SARI) to identify mutated influenza viruses affecting drug resistance, pathogenesis, and transmission. Methods: Oropharyngeal swab samples were collected from KINRESS and SARI during the 2018-2019 season. The specimens confirmed influenza virus using real-time RT-PCR on inoculated MDCK cells. HA and NA sequences of the influenza viruses were analyzed for phylogeny and mutations. Neuraminidase inhibition and hemagglutination inhibition assays were utilized to characterize the isolates. Results: Two A(H1N1)pdm09 isolates harboring an H275Y substitution in the neuraminidase sequence were detected in patients with acute hematologic cancer. They had prolonged respiratory symptoms, with the virus present in the respiratory tract despite oseltamivir and peramivir treatment. Through the neuraminidase inhibition assay, both the viruses were found to be resistant to oseltamivir and peramivir, but not to zanamivir. Although hemagglutinin and neuraminidase phylogenetic analyses suggested that the two A(H1N1)pdm09 isolates were not identical, their antigenicity was similar to that of the 2018-19 influenza vaccine virus. Conclusions: Our data indicate the utility of monitoring influenza-infected immunocompromised patients in general hospitals for the early detection of emerging neuraminidase inhibitor-resistant viruses and maintaining continuous laboratory surveillance of patients with influenza-like illness in sentinel clinics to monitor the spread of such new variants. Finally, characterization of the virus can inform the assessment of risk for future epidemics and pandemics caused by drug-resistant influenza viruses.

Methamphetamine is one of the widely abused drugs. Nevertheless, there is little predominant therapy for the abuse. In the previous study, acupuncture had shown to attenuate methamphetamine self-administration behavior, and based on, the present study investigated whether acupuncture inhibits the reinstatement of methamphetamine self-administration. As well, a possible neuronal mechanism was investigated. Male Sprague-Dawley rats weighing 270-300 g were trained to intravenously self-administer methamphetamine (0.1 mg/kg) for 3 weeks. Following training, rats who administered stable amount of methamphetamine underwent extinction period of 1 week. Thereafter, priming injection was performed to induce reinstatement, and acupuncture was given immediately before priming. In the second experiment, the selective antagonists of GABAA and GABAB receptors were treated prior to acupuncture to investigate a neuronal mechanism of GABAergic pathway. Acupuncture treatment at HT7, but not at the control acupoint LI5, reduced the active lever responses on the reinstatement session, showing that HT7 suppressed craving for methamphetamine induced by reexposure to the drug during abstinence. And, the effects of acupuncture were blocked by the GABA receptors' antagonists. In addition, HT7 did not influence saline self-administration, indicating that acupuncture effect was selective to the methamphetamine. Results of the present study show that acupuncture at HT7 suppresses reinstatement of methamphetamine self-administration behavior through the GABA receptor system without affecting the normal state. From the results, it may be suggested that acupuncture at HT7 can be a useful option in the treatment of methamphetamine addiction.

Isoflavones in soybeans are well-known phytoestrogens. Soy isoflavones present in conjugated forms are converted to aglycone forms during processing and storage. Isoflavone aglycones (IFAs) of soybeans in human diets have poor solubility in water, resulting in low bioavailability and bioactivity. Enzyme-mediated glycosylation is an efficient and environmentally friendly way to modify the physicochemical properties of soy IFAs. In this study, we determined the optimal reaction conditions for Deinococcus geothermalis amylosucrase-mediated α-1,4 glycosylation of IFA-rich soybean extract to improve the bioaccessibility of IFAs. The conversion yields of soy IFAs were in decreasing order as follows: genistein &gt, daidzein &gt, glycitein. An enzyme quantity of 5 U and donor:acceptor ratios of 1000:1 (glycitein) and 400:1 (daidzein and genistein) resulted in high conversion yield (average 95.7%). These optimal reaction conditions for transglycosylation can be used to obtain transglycosylated IFA-rich functional ingredients from soybeans.

The Phalaenopsis cultivar ‘Blanc Rouse’ was bred by the National Institute of Horticultural and Herbal Science (Wanju-gun, Korea) in 2013. The ‘Blanc Rouse’ cultivar was derived from a cross between the miniature cultivar P. ‘KV 600’ and P. ‘Kang 1’ in 2007. In total, 182 seedlings were planted and cultivated in a greenhouse. In 2010, one line was selected on the basis of performance for traits such as flower color, plant height, leaf shape, flower stalk length, and vigorous growth; this line was given the line code “07-003-164.” A second set of analyses was carried out on the selected line with respect to cultivation characteristics and uniformity tests at farms at three different sites in Korea. This hybrid had white-colored petals (WN155A), a purple-violet lip (PVN80B), and small-sized flowers. ‘Blanc Rouse’ produces approximately 39.4 flowers per flower stalk and two flower stalks per plant. The average flower stalk length is 43.5 cm. The general impression of the petals and sepals is that they exhibit a flat shape. It has an early-blooming habit that starts in late November under optimal culture conditions. The leaves of ‘Blanc Rouse’ grow horizontally and are approximately 17.3 cm in length and 6.2 cm in width. This cultivar possesses no genetic variation and is amenable to fast in vitro propagation and easy cultivation management because of its vigorous habit and diseases resistance.

Aripiprazole (ARP) is an atypical anti-psychotic drug widely used to treat schizophrenia and bipolar disorder. The pharmacological effects of ARP on cancer cells are still poorly understood. In this study, anti-cancer effects of ARP on various malignant tumor cells and its molecular mechanism were further carefully examined by using cell proliferation assay, xenograft mouse model, immunoblotting analysis, migration assay, luciferase reporter gene assay, kinase assay, and overexpression strategy. Treatment with ARP induced cytotoxicity in U251 glioma cells, MKN-1 gastric adenosquamous carcinoma cells, and CT26 colon carcinoma cells. ARP suppressed cell proliferation of LN428, MDA-MB-231, and HEK293 cells. Pro-apoptotic factors active caspase-3, -8, and -9, as well as p53, were upregulated, whereas the protein and mRNA levels of anti-apoptotic factor B-cell lymphoma 2 (Bcl-2) decreased. In agreement with the in vitro results, ARP compound also significantly suppressed the growth of tumor masses formed by injecting CT26 colon cancer cells into mice. ARP treatment also effectively decreased the migratory ability of U251 glioma cells by downregulating metalloproteinase-9. Levels of phosphorylated Src, phosphorylated phosphatidylinositide 3-kinase (PI3K), and phosphorylated signal transducer and activator of transcription 3 (STAT3) were significantly decreased following ARP treatment. ARP compound reduced the kinase activity of Src. Our studies suggest that Src may be an important target molecule linked to the antitumor effects of ARP.

본 연구는 초등학생 교우관계 문제를 개선할 수 있는 텃밭체험 프로그램을 개발하고 그 효과를 검증하여 창의적 체험활동에 활용할 수 있도록 하는 것에 목적을 두었다. 이를 위해 서울 소재 초등학교 3~4학년으로 구성된 텃밭체험 활동반을 대상으로 총 10회기의 체험 위주 활동프로그램을 구성하여 창의적 체험활동 시간을 통해 진행하고 사전사후검사를 통해 초등학생 교우관계 문제에 어떠한 영향을 가져왔는지 확인하였다. 통제지배, 자기중심성, 냉담, 사회적 억제, 비주장성, 과순응성, 자기희생, 과관여 8가지 하위척도의 교우관계 문제검사를 실시하였으며, 그 중 통제지배, 사회적억제, 과순응성 항목에서 유의한 결과를 보였다. 또한 체험활동 학생만족도를 조사하여 교우관계 문제와 상관관계가 있음을 확인하였다. 직접 작물을 가꾸고 수확하여 이용하는 체험 위주의 활동을 함께 즐겁게 수행하는 과정이 교우관계 증진에 도움을 줄 수 있을 것으로 보이며, 세부적인 활동에 대한 추가 연구가 필요하다.