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A layered graphene oxide/ethylenediamine (GO/EDA) composite film was developed by exposing aqueous GO liquid crystal (GOLC) coating to EDA vapor and its effects on the gas barrier performance of GO film were systematically investigated. When a GO/EDA coating with a thickness of approximately 1 μm was applied to a neat polyethylene terephthalate (PET) film, the resultant film was highly impermeable to gas molecules, particularly reducing the gas permeance up to 99.6% for He and 98.5% for H2 in comparison to the neat PET film. The gas barrier properties can be attributed to the long diffusion length through stacked GO nanosheets. The EDA can crosslink oxygen-containing groups of GO, enhancing the mechanical properties of the GO/EDA coating with hardness and elastic modulus values up to 1.14 and 28.7 GPa, respectively. By the synergistic effect of the viscoelastic properties of GOLC and the volatility of EDA, this coating method can be applied to complex geometries and EDA intercalation can be spontaneously achieved through the scaffold of the GOLC.

H2 selective dense pores are generated in a graphene oxide (GO) layer by thermal-decomposition of oxygen-functional groups under high pressure. The nanoporous GO membrane shows H2/CO2 selectivity of 12.1 and H2 permeability of 10360 Barrer.

High loading of aligned graphene filler is effective for fabricating polymer nanocomposites with drastically improved properties, while practical preparation of such composites remains elusive. This paper reports on a method of preparing polyimide (PI, BPDA/PDA) nanocomposites containing highly loaded graphene fillers that are uniformly aligned parallel to the coating substrate in the PI matrix. The highly aligned graphene/PI film was achieved by infiltrating water-soluble poly(amic acid) ammonium salt (PAAS) into the scaffold of the graphene oxide liquid crystal. After thermal treatment, a freestanding reduced graphene oxide/polyimide (rGO/PI) film was prepared with the imidization of PAAS and reduction of graphene oxide. Owing to the excellent mechanical properties of the infiltrated PI, the hardness and modulus of the rGO/PI film were as high as 0.9 GPa and 9.3 GPa, respectively. In addition, the rGO/PI film was highly conductive, with an electrical conductivity of 446 S/m, because of the well-connected electrical pathways of the highly loaded and aligned graphene sheets.

Free-floating micro-mobility as a mobility solution is becoming increasingly popular in cities. In this study, the travel patterns of free-floating electric bike-sharing service (FFEBSS) users before and during the COVID-19 pandemic were explored using big data and data mining. Existing real-time data studies provide a limited understanding of trip patterns and the characteristics of each user. Interpretations concerning the occurrence of life-changing events such as the COVID-19 pandemic are important. This study aimed to understand each user over 13 months comprising multiple time frames of market trends, seasonal change, and the COVID-19 pandemic outbreak. Multiple features were extracted from each user to explain the hidden data characteristics, and a data mining method was employed for clustering and evaluating user similarities with the extracted features. The results showed that FFEBSS users demonstrated a moderately stable travel pattern despite the COVID-19 pandemic, indicating the possibility of micro-mobilities being well adoptedas our future urban transportation.

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Purpose: The purpose of this study is to identify beauty teachers’ preference and capability assessment on the basis of types of makeup and clothing. Method: A survey was conducted on 216 students majoring in beauty high schools, colleges, and universities in Seoul. Factor analysis, variance analysis, and t -test were performed using SPSS version 24. Results: On the basis of makeup and clothing, preference of beauty teachers was categorized as Type 4 (Heavy Make-up and Modern Clothing), Type 2 (Heavy Make-up and Casual Clothing), Type 3 (No Makeup and Modern Clothing), and Type 1 (No Make-up and Casual Clothing). During the capability assessment, personality factors were placed as Type 4, Type 1, Type 2, and Type 3, and specialty factors were arranged as Type 4, Type 3, Type 2, Type 1. Preference of beauty teachers based on make-up and clothing of men and women differed between Types 1 and 2. However, no difference was found between Types 3 and 4. In the case of capability assessment, female students valued the ability of Types 2 and 4, but male students valued the ability of Types 1 and 3. Preference of beauty teachers belonging to different types of beauty schools on the basis of types of make-up and clothing differed from Type 2 to Type 4. Conclusion: Differences were identified in preference and capability assessment of beauty teachers not only on the basis of types of make-up and clothing but also gender and their school type.

The preparation of carbon materials based hydrogels and their viscoelastic properties are essential for their broad application and scale-up. However, existing studies are mainly focused on graphene derivatives and carbon nanotubes, and the behavior of graphene nanoribbon (GNR), a narrow strip of graphene, remains elusive. Herein, we demonstrate the concentration-driven gelation of oxidized GNR (graphene oxide nanoribbon, GONR) in aqueous solvents. Exfoliated individual GONRs sequentially assemble into strings (∼1 mg/mL), nanoplates (∼20 mg/mL), and a macroporous scaffold (50 mg/mL) with increasing concentration. The GONR hydrogels exhibit viscoelastic shear-thinning behavior and can be shear-coated to form large-area GONR films on substrates. The entangled and stacked structure of the GONR film contributed to outstanding nanofiltration performance under high pressure, cross-flow, and long-term filtration, while the precise molecular separation with 100% rejection rate was maintained for sub-nanometer molecules.

목적: 본 연구는 여대생들의 얼굴 만족여부에 따른 얼굴 이미지 인식과 외모관리행동을 파악하고자 하였다. 방법: 총 322부가 최종분석에 사용되었으며, SPSS ver. 23.0 프로그램을 이용하여 빈도 분석, 요인 분석, 신뢰도 분석, 상관 분석 및 t-test 등을 실시하였다. 결과: 얼굴 이미지 인식을 분석한 결과, 전체조화·피부, 이목구비·헤어, 얼굴형태의 순서로 중요도를 인식하며, 이목구비·헤어, 전체조화·피부, 얼굴형태의 순서로 만족하는 것으로 나타났다. 또한 얼굴 중요도는 높으나 얼굴 만족도는 상대적으로 낮게 나타났다. 이후 얼굴 만족여부를 저만족 집단과 고만족 집단으로 나누어 살펴본 결과, 얼굴 저만족 집단이 얼굴 고만족 집단보다 얼굴 중요도를 좀 더 높게 평가하고 있었고, 얼굴 만족도에서 통계적으로 유의한 차이를 보였다. 외모관리행동에서 얼굴 저만족 집단은 자신의 얼굴에 대한 저만족을 성형, 메이크업, 헤어관리 등을 통하여 보완하려는 것으로 나타났다. 그러나 피부관리, 체중조절에서는 통계적으로 유의한 차이를 보이지 않았다. 결론: 본 연구는 여대생들의 얼굴 만족여부에 따라 얼굴 이미지 인식과 외모관리행동에 차이가 있음을 확인하였다. 본 연구결과를 바탕으로 향후 뷰티 산업의 잠재 고객인 여대생들에게 얼굴을 비롯한 외모에 대한 올바른 인식을 가지도록 교육할 필요가 있다고 사료된다.

Herein, a functionalized nanoporous graphene (FNG) membrane was developed to mitigate the contemporary issues affecting graphene oxide (GO) membranes, such as the low flux induced by its long tortuosity and poor membrane stability in aqueous solvents. GO was thermally activated at 650 °C to prepare a nanoporous carbon sheet with a turbostratic structure (pore size

Graphene oxide (GO) has been widely used for the fabrication of nanofiltration membranes because precise molecular sieving can be achieved through the narrow interlayer spacing between stacked GO sheets. Herein, the scalable and continuous fabrication of a GO membrane is demonstrated by using a slot-die coater at a coating speed of 6 mm s−1. The thickness of the GO membrane can be controlled in 100-nm scale depending on the concentration of the GO solution and substrate morphology. Moreover, the coating layer and d-spacing (6.5–7.5 A) of the GO membrane is preserved, even in aqueous solution, as GO is partially reduced by NaOH treatment (so-called deoxygenated GO, dGO). A membrane performance test reveals that the dGO membrane is effective for filtering sub-nanometer-size dye molecules with a rejection rate of up to 99% (brilliant blue G) and a pure water permeance of 30 LMH bar−1. The dGO membrane operates stably under cross-flow and high pressure up to 12 bar. Scale-up of the GO membrane fabrication using the slot-die coating technique is feasible because the coating process is continuous.

Amitriptyline is a tricyclic antidepressant that is metabolized mainly by CYP2C19 and CYP2D6 enzymes. Higher plasma levels of amitriptyline and its active metabolite, nortriptyline, are associated with an increased risk of adverse events including anticholinergic effects. The aim of this study was to evaluate the effects of CYP2C19 and CYP2D6 genetic polymorphisms on amitriptyline and nortriptyline pharmacokinetics. Twenty-four Korean healthy adult male volunteers were enrolled in the study after stratification by their CYP2C19 and CYP2D6 genotypes. Serial blood draws for pharmacokinetic analysis were made after a single oral 25-mg dose of amitriptyline was administered. Plasma amitriptyline and nortriptyline concentrations were measured by a validated liquid chromatography with tandem mass spectrometry. Population pharmacokinetic modeling analysis was conducted using NONMEM, which evaluated the effects of CYP2C19 and CYP2D6 genotypes on amitriptyline and nortriptyline pharmacokinetics. The biotransformation of amitriptyline into nortriptyline was significantly different between subjects with the CYP2C19*2/*2, *2/*3, and *3/*3 genotypes and those with the other genotypes, with an estimated metabolic clearance of 17 and 61.5 L/h, respectively. Clearance of amitriptyline through pathways other than biotransformation into nortriptyline was estimated as 18.8 and 30.6 L/h for subjects with the CYP2D6*10/*10 and *10/*5 genotypes and those with the other genotypes, respectively. This study demonstrated a quantitative effect of the CYP2C19 and CYP2D6 genotypes on amitriptyline and nortriptyline pharmacokinetics. Production of nortriptyline from amitriptyline was associated with CYP2C19 genotypes, and clearance of amitriptyline through pathways other than biotransformation into nortriptyline was associated with CYP2D6 genotypes. These observations may be useful in developing individualized, optimal therapy with amitriptyline.

Aim: To investigate the combined effects of SLCO1B1 and ABCB1 genotypes on the pharmacokinetics of simvastatin and its active metabolite simvastatin acid, in relation to CYP3A4 inhibition. Methods: We conducted a single-dose pharmacokinetic study of simvastatin in 26 healthy volunteers screened for their SLCO1B1 c.521T>C and ABCB1 c.1236C>T–2677G>T–3435C>T genotypes, with and without amlodipine pretreatment. The genetic effects and drug-interaction effect on simvastatin pharmacokinetic parameters were analyzed using a linear-mixed model. Results: The SLCO1B1 c.521T>C variant significantly increased exposure to simvastatin acid by around 40% (p < 0.05), similar to that caused by the amlodipine pretreatment. The ABCB1 gene showed no influence on exposure to simvastatin or simvastatin acid. Conclusion: Only SLCO1B1, not ABCB1 genotype, is likely to be associated with simvastatin-induced myopathy. SLCO1B1 genotyping may be particularly beneficial in simvastatin users who are co-administered CYP3A4 inhibitors.

Background. The ability to induce and maintain antigen-specific immunologic tolerance is the ultimate goal in allotransplantation. Here, we report that the transplantation of unmanipulated murine pancreatic islets across the HY disparity induced transplantation tolerance that prevented HY-mismatched skin grafts being rejected. Methods. Three hundred islet equivalent of freshly isolated islets from male C57BL/6 donor mice was transplanted underneath the kidney capsule of syngeneic female recipients rendered diabetic by streptozotocin. Nephrectomy was carried out to remove the islet graft and retransplantation was performed using the contralateral kidney. For skin transplantation, donor tail skin was transplanted onto the lateral thorax. Results. Islets from male C57BL/6 donors transplanted to syngeneic female recipients cured diabetes and the mice survived indefinitely. The acceptance of second grafts and rejection of third party islet grafts indicated antigen-specific transplantation tolerance. However, flow cytometry and ELISPOT analysis demonstrated that the HY-specific T cells were not deleted or anergized. A 2-fold increase of CD4 + Foxp3 + regulatory T cells (Tregs) was observed in spleen and lymph nodes. Notably, CD25 - Tregs increased threefold over levels in naive mice. Adoptive transfer of CD4 + T cells to neonatal mice could transfer tolerance. At the graft site in long-term tolerant mice, CD4 + T cells, 40% of which were CD4 + Foxp3 + Tregs (43% CD25 - , 57% CD25 + ) infiltrated the peri-islet spaces. Conclusions. Unmanipulated pancreatic islets can induce immunologic tolerance associated with peripherally induced CD4 + Foxp3 + Tregs, a significant proportion of which notably are CD25 - .

Nucleic acid amplification techniques are used frequently for rapid diagnosis of viral diseases. In this study, a real-time polymerase chain reaction protocol that uses primers specific for the viral VP4 gene and the commercial SYBR Green reagent were evaluated for the quantitative measurement of human rotavirus (HRV) RNA in human stool specimens. SYBR Green I detection involved analysis of the melting temperature of the PCR product and measurement of fluorescence at the optimum temperature. The assay resulted in a sensitive and reproducible detection of targets ranging from low (10(2)rotavirus cDNA copies/reaction) to high numbers (10(6)rotavirus cDNA copies/reaction). No cross-reaction was found with crude cell culture stocks of coxsackievirus, echovirus, poliovirus, hepatitis A virus and adenovirus. Analysis with the HRV cDNA standard demonstrated high reproducibility with a coefficient of variation (CV) of 0.2-0.9%. Daily performance among three different laboratories showed a CV no greater than 8%, indicating an intermediate level of variation. These results demonstrate the feasibility of this method for quantitative analysis of human rotavirus in clinical samples.

Protection of pancreatic islet beta cells from pro-inflammatory cytokines-induced cell death and functional impairment is a key issue in developing therapeutic interventions of type 1 diabetes mellitus including islet transplantation. The effects of IL-6 on the protection of beta cells in vitro and in vivo were examined. Freshly isolated islets or MIN6 beta cells, when pre-incubated with IL-6, showed significantly higher viabilities measured by MTT assay and FACS analysis of PI stained cells against pro-apoptotic signaling delivered by IL-1beta, TNF-alpha and IFN-gamma. Insulin secretory function was also significantly protected in static culture with glucose and KCl stimulation. In vivo assessment using marginal mass syngeneic islet transplantation in mouse model revealed IL-6 conferred significantly better blood glucose control and graft survival rate over 50 days. Conclusively, IL-6 protects pancreatic islets or beta-cells from inflammatory cytokines-induced cell death and functional impairment both in vitro and in vivo. This strategy could be exploited in the clinical setting to maintain functional islet mass.

The aim of this study was to examine the effects of CYP2C19*2 and *3 genetic polymorphisms on omeprazole pharmacokinetic (PK) and pharmacodynamic (PD) responses. Twenty-four healthy Korean volunteers were enrolled and given 20 mg omeprazole orally once daily for 8 days. The genotypes of CYP2C19 single nucleotide polymorphisms (SNPs) (*2, *3, and *17) were screened. The plasma concentrations of omeprazole, omeprazole sulfone, and 5-hydroxy (5-OH) omeprazole were determined by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The noncompartmental method was used for the determination of PK parameters. Change of mean pH and proportion (%) of time of gastric pH above 4.0 were estimated. The poor metabolizer (PM) group had the lowest metabolic ratio and exhibited the highest area under the curve (AUC) for omeprazole among the CYP2C19 phenotype groups. The PM group showed the greatest change of mean pH and the highest % time of gastric pH above 4.0. The relationship between AUC of omeprazole and % time of gastric pH above 4.0 was confirmed. The study demonstrates that CYP2C19*2 and *3 influence the PKs and PDs of omeprazole in Korean healthy volunteers. Clinical trial registry at the U.S. National Institutes of Health (https://clinicaltrials.gov), number NCT02299687., Graphical Abstract

The embryonic stem cell test (EST) is a validated in vitro embryotoxicity test; however, as the inhibition of cardiac differentiation alone is used as a differentiation endpoint in the EST, it may not be a useful test to screen embryotoxic chemicals that affect the differentiation of noncardiac tissues. Previously, methylmercury (MeHg), cadmium and arsenic compounds, which are heavy metals that induce developmental neurotoxicity in vivo, were misclassified as nonembryotoxic with the EST. The aim of this study was to improve the EST to correctly screen such developmental neurotoxicants. We developed a neuronal endpoint (Tuj-1 ID₅₀) using flow cytometry analysis of Tuj-1-positive cells to screen developmental neurotoxicants (MeHg, valproic acid, sodium arsenate and sodium arsenite) correctly using an adherent monoculture differentiation method. Using Tuj-1 ID₅₀ in the EST instead of cardiac ID₅₀, all of the tested chemicals were classified as embryotoxic, while the negative controls were correctly classified as nonembryotoxic. To support the validity of Tuj-1 ID₅₀) , we compared the results from two experimenters who independently tested MeHg using our modified EST. An additional neuronal endpoint (MAP2 ID₅₀), obtained by analyzing the relative quantity of MAP2 mRNA, was used to classify the same chemicals. There were no significant differences in the three endpoint values of the two experimenters or in the classification results, except for isoniazid. In conclusion, our results indicate that Tuj-1 ID₅₀ can be used as a surrogate endpoint of the traditional EST to screen developmental neurotoxicants correctly and it can also be applied to other chemicals.

This study was performed to investigate whether compression/stretching of the spermatic cord or blunt dissection influences testicular development and fertility. In addition, the authors evaluated whether the extents of testicular damage differ between these 2 surgical manipulations.Forty-four prepubertal male Sprague-Dawley (SD) rats (Harlan Sprague-Dawley Inc, Indianapolis, Ind) were divided into 3 groups: (1) the control group (CG) animals underwent a sham operation in the right groin, (2) the experimental group 1 (EG1) underwent compression/stretching of the right spermatic cord, and (3) the experimental group 2 (EG2) underwent dissection around the right spermatic cord structures. Testicular volumes, weights, mean seminiferous tubular diameters (MSTDs), mean testicular biopsy scores, and numbers of offspring and of pregnant females were evaluated.Right (operative) and left (nonoperative) testicular volumes were smaller in the EG2 group than in the CG or EG1 groups. Left MSTDs in the EG1 and EG2 groups increased more than in the CG group. Numbers of Sertoli cells in left testes differed in the 3 groups, in the order EG1CGEG2. Mean testicular biopsy scores, offspring numbers, and pregnant female numbers were no different in the 3 groups.Both surgical manipulations influenced testicular growth, but they did not compromise spermatogenesis or fertility in SD rats.

The ability to induce and maintain antigen-specific immunologic tolerance is the ultimate goal in allo-transplantation. Here, we report that the transplantation of unmanipulated murine pancreatic islets across the HY disparity induced transplantation tolerance that prevented HY-mismatched skin grafts being rejected.Three hundred islet equivalent of freshly isolated islets from male C57BL/6 donor mice was transplanted underneath the kidney capsule of syngeneic female recipients rendered diabetic by streptozotocin. Nephrectomy was carried out to remove the islet graft and retransplantation was performed using the contralateral kidney. For skin transplantation, donor tail skin was transplanted onto the lateral thorax.Islets from male C57BL/6 donors transplanted to syngeneic female recipients cured diabetes and the mice survived indefinitely. The acceptance of second grafts and rejection of third party islet grafts indicated antigen-specific transplantation tolerance. However, flow cytometry and ELISPOT analysis demonstrated that the HY-specific T cells were not deleted or anergized. A 2-fold increase of CD4+Foxp3+ regulatory T cells (Tregs) was observed in spleen and lymph nodes. Notably, CD25- Tregs increased threefold over levels in naïve mice. Adoptive transfer of CD4+ T cells to neonatal mice could transfer tolerance. At the graft site in long-term tolerant mice, CD4+ T cells, 40% of which were CD4+Foxp3+ Tregs (43% CD25-, 57% CD25+) infiltrated the peri-islet spaces.Unmanipulated pancreatic islets can induce immunologic tolerance associated with peripherally induced CD4+Foxp3+ Tregs, a significant proportion of which notably are CD25-.

Human cytomegalovirus UL18, a MHC class I homologue, is known to serve as a natural killer cell (NK) decoy and to ligate NK inhibitory receptors to prevent lysis of an infected target cell. To explore whether the cell surface expression of UL18 represents a potential immune suppressive approach to evade NK-mediated cytotoxicity in the prevention of xenograft rejection, we examined the effect of the UL18 expression in vitro upon human NK-mediated cytotoxicity against swine endothelial cells (SECs). UL18 expression on SECs by a retroviral vector (PLNCX2) significantly suppressed NK-mediated SEC lysis by approximately 25–100%. The protective effect of UL18 could be mediated through ILT-2 inhibitory receptor on NKs. Additionally, the interaction between UL18 and NKs resulted in the significant reduction of IFN-γ production. This study demonstrates that UL18 can serve as an effective tool for the evasion of NK-mediated cytotoxicity and for the inhibition of IFN-γ production during xenograft rejection.

Background: Minor histocompatibility HY antigen, as a transplantation antigen, has been known to cause graft rejection in MHC (major histocompatibility complex) matched donor-recipient. The aim of our study is to investigate the role of male antigen (HY) disparity on MHC matched pancreatic islet transplantation and to examine the mechanism of the immune reaction. Methods: Pancreatic islets were isolated and purified by collagen digestion followed by Ficoll gradient. The isolated islets of male C57BL6/J were transplanted underneath the kidney capsule of syngeneic female mice rendered diabetic with streptozotocine. Blood glucose was monitored for the rejection of engrafted islets. After certain period of time, tail to flank skin transplantation was performed either on mouse transplanted with HY mismatched islets or on sham treated mouse. The rejection was monitored by scoring gross pathology of the engrafted skin. Results: HY mismatched islets survived more than 300 days in 14 out of 15 mice. The acceptance of second party graft (male B6 islets) and the rejection of third party graft (male BALB/c islets) in these mice suggested the tolerance to islets with HY disparity. B6 Skin with HY disparity was rejected on day . However, HY mismatched skin transplanted on the mice tolerated to HY mismatched islets survived more than 240 days. Tetramer staining in these mice indicated the CTL recognizing MHC Db/Uty was not deleted or anergized. Conclusion: The islet transplantation across HY disparity induced tolerance to HY antigen in C57BL6 mouse, which in turn induced tolerance to HY mismatched skin, which otherwise would be rejected within 25 days. The MHC tetramer staining suggested the underlying mechanisms would not be clonal deletion or anergy.

【The aim of this study was to evaluate the posterior sagittal anorectoplasty (PSARP) as a re-do operation in patients who failed initial repair of anorectal malformation. Nine patients (4 boys and 5 girls) who had previous failed surgery for anorectal malformation underwent secondary operations through posterior sagittal approach. The main reasons of surgery were constipation (n=3) and persistent anatomical derangement in spite of previous correction surgery (n=6). In addition to constipation, the former group (n=3) had various anatomical defects, and the latter group (n=6), of course, had constipation in some degrees. Patients ranged in age from 2 to 19 years (median 3 years) with only one over the age of 6 years. The primary procedures included PSARP (n=8) and anoplasty (n=1). The rectum was mobilized from surrounding structures through posterior sagittal approach and anatomical defects were corrected. The rectum underwent reconstruction, which involved relocation of the rectum and anus within the limits of the intact muscle complex. Patients underwent follow-up for periods ranging from 6 to 77 months (mean 37 months) after surgery. Anatomical corrections of all the defects were successfully fulfilled in 9 patients. All the patients were satisfied with the functional results after redo-PSARP compared with the preoperative defecatory function. This study suggests that (1) some of the patients with troublesome constipation may have anatomical defects, prominent or hidden, (2) surgeons should suspect the possibility of anatomical defect as the cause of incontinence and (3) preoperative thorough investigation to reveal the anatomical defects should be included in estimating patients with severe incontinence after previous surgery and planning the correction for failed previous surgery as well.】