Publications by authors named "Dong-Seob Kim"

Helical spin structures are expressions of magnetically induced chirality, entangling the dipolar and magnetic orders in materials. The recent discovery of helical van der Waals multiferroics down to the ultrathin limit raises prospects of large chiral magnetoelectric correlations in two dimensions. However, the exact nature and magnitude of these couplings have remained unknown so far.

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Article Synopsis
  • - The study assessed COVID-19 vaccination effectiveness in high-risk facilities in South Korea during the Delta variant surge, comparing medical and non-medical institutions.
  • - Data from 8 outbreak clusters (243 cases and 895 contacts) were analyzed, revealing lower attack rates in medical institutions, but non-medical institutions showed higher vaccine effectiveness for severe disease and death.
  • - Overall, the findings emphasized the need for targeted vaccination strategies and effective management in high-risk settings to improve public health responses.
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Moiré superlattices host a rich variety of correlated electronic phases. However, the moiré potential is fixed by interlayer coupling, and it is dependent on the nature of carriers and valleys. In contrast, it has been predicted that twisted hexagonal boron nitride (hBN) layers can impose a periodic electrostatic potential capable of engineering the properties of adjacent functional layers.

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Transition metal dichalcogenide heterostructures provide a versatile platform to explore electronic and excitonic phases. As the excitation density exceeds the critical Mott density, interlayer excitons are ionized into an electron-hole plasma phase. The transport of the highly non-equilibrium plasma is relevant for high-power optoelectronic devices but has not been carefully investigated previously.

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A long-standing pursuit in materials science is to identify suitable magnetic semiconductors for integrated information storage, processing, and transfer. Van der Waals magnets have brought forth new material candidates for this purpose. Recently, sharp exciton resonances in antiferromagnet NiPS have been reported to correlate with magnetic order, that is, the exciton photoluminescence intensity diminishes above the Néel temperature.

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As the elderly population increases due to an aging society, the number of patients with catheters is increasing, and treatment for urinary infections is needed. The current study analyzed the effectiveness of fosfomycin, the primary antibiotic used to treat urinary tract infections (UTIs), in these patients. Patients who received fosfomycin as the primary antibiotic for a UTI were selected, and the results of urine tests and cultures before and after fosfomycin administration were compared and analyzed.

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In van der Waals (vdW) heterostructures formed by stacking two monolayers of transition metal dichalcogenides, multiple exciton resonances with highly tunable properties are formed and subject to both vertical and lateral confinement. We investigate how a unique control knob, the twist angle between the two monolayers, can be used to control the exciton dynamics. We observe that the interlayer exciton lifetimes in MoSe_{2}/WSe_{2} twisted bilayers (TBLs) change by one order of magnitude when the twist angle is varied from 1° to 3.

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Mulberry leaves have antioxidant activity and anti‑inflammatory effects in several types of cells. However, the efficacy of mulberry leaves fermented with Cordyceps militaris remains unknown. Therefore, the present study aimed to investigate whether the ethanol extracts of mulberry leaves fermented with C.

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Perilla oil has been considered to have excellent potential for treating various diseases due to its contents of beneficial fatty acids, such as α-linolenic acid, oleic acid and linoleic acid. The therapeutic effects and molecular mechanism of an α-linolenic acid-enriched cold-pressed perilla oil (LEP) on hepatic steatosis of an obesity model were investigated by analyzing alterations in fat accumulation and endoplasmic reticulum (ER) stress-mediated autophagy, in high-fat diet (HFD)-induced obesity C57BL/6N mice treated with LEP for 16 weeks. Although no significant alterations were detected in body weight and most organ weights, the liver weight and accumulation of lipid droplets in the liver section were significantly lower in HFD + LEP treated group as compared to the HFD + Vehicle treated group.

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Identifying material parameters affecting properties of ferromagnets is key to optimized materials that are better suited for spintronics. Magnetic anisotropy is of particular importance in van der Waals magnets, since it not only influences magnetic and spin transport properties, but also is essential to stabilizing magnetic order in the two-dimensional limit. Here, we report that hole doping effectively modulates the magnetic anisotropy of a van der Waals ferromagnet and explore the physical origin of this effect.

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This study aimed to examine the awareness and the work-related factors associated with scrub typhus to provide data essential for evidence-based preventive strategies. A community-based case control study was carried out in the rural areas of Gyeongsangbuk-do, South Korea. Confirmed cases of scrub typhus ( = 57) were based on laboratory tests performed by the Korean Centers for Disease Control and Prevention (KCDC), 114 matched neighborhood controls, age (±6 years), gender and area of residence in the Gyeongsangbuk-do of South Korea.

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Backgroud: Use of multifunctional drugs with neurotrophic supporting and oxidative stress suppressing activity may be considered a therapeutic strategy to protect or repair cellular damage caused during the progression of Alzheimer's disease (AD). In this study, we investigated the therapeutic effects of aqueous extract of A. cochinchinesis root (AEAC), particularly its role as a nerve growth factor (NGF) stimulator and anti-oxidant in Tg2576 mice showing AD phenotypes of human.

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Asthma is a chronic inflammatory disease characterized by T-lymphocyte and eosinophil infiltration, mucus overproduction and airway hyper-responsiveness. The present study examined the therapeutic effects and action mechanism of a saponin-enriched extract of Asparagus cochinchinensis (SEAC) on airway inflammation and remodeling in an ovalbumin (OVA)-induced asthma model. To accomplish this, alterations of the nitric oxide (NO) level, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression levels, as well as variations in immune cell numbers, immunoglobulin E (IgE) concentration, histopathological structure and inflammatory cytokine levels were measured in lipopolysaccharide (LPS)-activated RAW264.

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The inhibitory effects of against inflammatory response induced by lipopolysaccharide (LPS), substance P and phthalic anhydride (PA) treatment were recently reported for some cell lines and animal models. To evaluate the hepatotoxicity and nephrotoxicity of toward the livers and kidneys of ICR mice, alterations in related markers including body weight, organ weight, urine composition, liver pathology and kidney pathology were analyzed in male and female ICR mice after oral administration of 150, 300 and 600 mg/kg body weight/day saponin-enriched extract of (SEAC) for 14 days. The saponin, total flavonoid and total phenol levels were found to be 57.

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Asparagus cochinchinesis (A. cochinchinesis) is a medicine traditionally used to treat fever, cough, kidney disease, breast cancer, inflammatory disease and brain disease in northeast Asian countries. Although numerous studies of the anti‑inflammatory effects of A.

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This study was conducted to evaluate the hyaluronidase (HAase) inhibition activity of (AC) extracts following fermentation by through response surface methodology. To optimize the HAase inhibition activity, a central composite design was introduced based on four variables: the concentration of AC extract (: 1-5%), amount of starter culture (: 1-5%), pH (: 4-8), and fermentation time (: 0-10 days). The experimental data were fitted to quadratic regression equations, the accuracy of the equations was analyzed by ANOVA, and the regression coefficients for the surface quadratic model of HAase inhibition activity in the fermented AC extract were estimated by the test and the corresponding values.

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Asparagus cochinchinensis has been used to treat various diseases including fever, cough, kidney disease, breast cancer, inflammatory disease and brain disease, while IL-4 cytokine has been considered as key regulator on the skin homeostasis and the predisposition toward allergic skin inflammation. However, few studies have investigated its effects and IL-4 correlation on skin inflammation to date. To quantitatively evaluate the suppressive effects of ethyl acetate extracts of A.

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To quantitatively evaluate the therapeutic effects of diosgenin (DG) and investigate the role of IL-4 on skin inflammation, alterations in luciferase-derived signal and general phenotype biomarkers were measured in IL-4/Luc/CNS-1 transgenic mice with phthalic anhydride (PA)-induced skin inflammation after treatment with DG for 4 weeks. High levels of luciferase-derived signal detected in the abdominal region and submandibular lymph node (SL) of the PA treated group was significantly decreased by 67-88% in the PA + DG cotreated group. Furthermore, the weight of the lymph node and spleen, IgE concentration, epidermis thickness, and number of infiltrated mast cells were lower in the PA + DG treated group than the PA + Vehicle treated group.

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Introduction: The management of pediatric poisoning is dependent on the type of toxicant ingested; however, little information has been published regarding the difference in poisoning by pharmaceuticals and nonpharmaceuticals in children. We compared the accidental poisoning of children younger than 3 years who had ingested pharmaceuticals or nonpharmaceuticals using emergency medical information center data.

Methods: We retrospectively reviewed the records of the poisonings of children younger than 3 years who were evaluated by the Seoul Emergency Medical Information Center in 2011.

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Introduction: A high-flow nasal cannula (HFNC) has been used to treat patients with dyspnea. We identified changes in arterial blood gas (ABG) of patients visiting the emergency department (ED) with hypercapnic and nonhypercapnic respiratory failure after use of an HFNC.

Methods: This study was a retrospective chart review of patients with respiratory failure who visited the hospital and used an HFNC in the ED.

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Objective: This study was conducted to evaluate the appropriateness of the chest compression (CC) depth recommended in the current guidelines and simulated external CCs, and to characterize the optimal CC depth for an adult by body mass index (BMI).

Methods: Adult patients who underwent chest computed tomography as a screening test for latent pulmonary diseases in the health care center were enrolled in this study. We calculated the internal anteroposterior (AP) diameter (IAPD) and external AP diameter (EAPD) of the chest across BMIs (<18.

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Although the rapid and accurate diagnosis of both acute ischemic stroke and extremity ischemia is essential to the timely and appropriate treatment, it is not always easy to differentiate between true stroke and stroke mimics. Although in general, limb ischemia due to extremity embolism is not included in stroke mimics or misdiagnosis, limb arterial embolism should be considered in thedifferential diagnosis of acute monoparesis because the diagnosis maybe missed if the other typical manifestations of this presentation(pain, pallor, pulselessness, sensory loss, and coolness of the arm) are overlooked. Therefore, it is important to ensure that important signsare not missed whether the evaluation of the patient is done at thebedside.

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Chlorfenapyr has been used worldwide for agricultural pest control since 1995. Despite its widespread use, acute human poisoning data are insufficient; only a small number of fatalities from chlorfenapyr poisoning have been reported. The signs and symptoms of chlorfenapyr toxicity include nausea, vomiting, fever, rhabdomyolysis, among others.

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Among the many complications that may follow envenomation by some species of venomous snakes, coagulopathy is common and well known. However, hemoperitoneum induced by coagulopathy after a snakebite is rare. Atraumatic spontaneous splenic rupture is also an uncommon and life-threatening condition.

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The objectives of this study was to improve poly-γ-glutamic acid (γ-PGA) production by Bacillus subtilis D7 isolated from a Korean traditional fermented food and to assess its antioxidant activity for applications in the cosmetics and pharmaceutical industries. Strain D7 produced γ-PGA in the absence of L-glutamic acid, indicating L-glutamic acid-independent production. However, the addition of L-glutamic acid increased γ-PGA production.

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