Aluminum-free low-modulus Ti–C composites that exhibit reduced image artifacts during MRI

Kim, Sung-Chul,Lee, Hong-Jun,Son, Seong-Guk,Seok, Hyun-Kwang,Lee, Kang-Sik,Shin, Seung-Young,Lee, Jae-Chul Elsevier 2015 ACTA BIOMATERIALIA Vol.12 No.-

<P><B>Abstract</B></P> <P>Feasibility studies were performed to determine the suitability of a novel synthesis technique for fabricating multifunctional composite materials for orthopedic implants. By blending paramagnetic Ti powder with diamagnetic graphite and consolidating the resulting mixtures, Ti–C composites that cannot be feasibly obtained via conventional alloying techniques or ingot metallurgy were synthesized. The synthesized composite material exhibited extremely low magnetic susceptibility (χ=67.6×10<SUP>−6</SUP>), and, as a result, exhibited fewer artifacts during magnetic resonance imaging. The strength of the composite material (σ=770MPa) was such that it could support external loads to which the human body is subjected, but its Young’s modulus was low (<I>E</I> =81.9 GPa) such that it could mitigate the stress-shielding effect. The material was also free from toxic elements such as Al and V and, thus, can be considered less harmful.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Neuroprotective effects of bovine colostrum on intracerebral hemorrhage-induced apoptotic neuronal cell death in rats

Kim, Sung Eun,Ko, Il Gyu,Shin, Mal Soon,Kim, Chang Ju,Ko, Young Gwan,Cho, Hanjin Medknow PublicationsMedia Pvt Ltd 2012 Neural regeneration research Vol.7 No.22

<P>Brain cell death after intracerebral hemorrhage may be mediated in part by an apoptotic mechanism. Colostrum is the first milk produced by mammals for their young. It plays an important role in protection and development by providing various antibodies, growth factors and nutrients, and has been used for various diseases in many countries. In the present study, we investigated the anti-apoptotic effects of bovine colostrum using organotypic hippocampal slice cultures and an intracerebral hemorrhage animal model. We performed densitometric measurements of propidium iodide uptake, a step-down avoidance task, Nissl staining, and caspase-3 immunohistochemistry. The present results revealed that colostrum treatment significantly suppressed N-methyl-D-aspartic acid-induced neuronal cell death in the rat hippocampus. Moreover, colostrum treatment improved short-term memory by suppressing hemorrhage-induced apoptotic neuronal cell death and decreasing the volume of the lesion induced by intracerebral hemorrhage in the rat hippocampus. These results suggest that colostrum may have a beneficial role in recovering brain function following hemorrhagic stroke by suppressing apoptotic cell death.</P>

Poly(vinyl alcohol) nanocomposites containing reduced graphene oxide coated with tannic acid for humidity sensor

Lim, Min-Young,Shin, Huiseob,Shin, Dong Myung,Lee, Sang-Soo,Lee, Jong-Chan Elsevier 2016 Polymer Vol.84 No.-

<P><B>Abstract</B></P> <P>Poly(vinyl alcohol) (PVA) nanocomposites were prepared by a solution casting method using a reduced graphene oxide coated with tannic acid (rGO-TA) as a filler. The rGO-TA was simply prepared by mixing tannic acid (TA) with graphene oxide (GO). The simple mixing process was found to be effective to reduce GO and to produce covalently-grafted TA layers on the reduced GO. The mechanical properties of PVA were much improved by the addition of rGO-TA because the TA layers increased the compatibility of the reduced GO with PVA matrix. For example, Young's modulus and elongation at break values of PVA were increased by 34.0 and 56.9%, respectively, by adding 1.0 wt% of rGO-TA. In addition, the PVA nanocomposites showed excellent humidity sensing properties over the wide relative humidity range and the long-term stability due to the conductive property of the reduced GO and the enhanced mechanical strength by the effective incorporation of rGO-TA into the PVA matrix.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The rGO-TA was prepared by a facile and green method using a low-cost tannic acid. </LI> <LI> The effect of rGO-TA on the properties of PVA nanocomposites has been studied. </LI> <LI> The rGO-TA improved the important properties for PVA-based humidity sensors. </LI> <LI> The PVA/rGO-TAs are promising materials for high-performance humidity sensors. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Contribution of stress and coping strategies to problematic Internet use in patients with schizophrenia spectrum disorders

Lee, Ju-Yeon,Chung, Young-Chul,Song, Je-Heon,Lee, Yo-Han,Kim, Jae-Min,Shin, Il-Seon,Yoon, Jin-Sang,Kim, Sung-Wan Elsevier 2018 Comprehensive psychiatry Vol.87 No.-

<P><B>Abstract</B></P> <P><B>Introduction</B></P> <P>Internet use is already high and increasing rapidly among people with psychotic disorders, but there have been few studies on problematic Internet use (PIU) among patients with schizophrenia spectrum disorders. This study aimed to measure the prevalence of PIU and identify the factors associated with PIU among patients with schizophrenia spectrum disorders.</P> <P><B>Methods</B></P> <P>A cross-sectional survey was performed that included 368 outpatients with schizophrenia spectrum disorders: 317 with schizophrenia, 22 with schizoaffective disorder, 9 with schizophreniform disorder, and 20 with other schizophrenia spectrum and psychotic disorders. The severity of psychotic symptoms and levels of personal and social functioning were assessed by the Clinician-rated Dimensions of Psychosis Symptom Severity (CRDPSS) scale and the Personal and Social Performance (PSP) scale, respectively. PIU was evaluated using Young's Internet Addiction Test (IAT). Additionally, the Hospital Anxiety and Depression Scale (HADS), Perceived Stress Scale (PSS), Rosenberg Selfesteem Scale (RSES), and Brief Coping Orientation to Problems Experienced (COPE) Inventory were administered.</P> <P><B>Results</B></P> <P>PIU was identified in 81 (22.0%) of the 368 patients with schizophrenia spectrum disorders. Subjects with PIU were significantly younger and more likely to be male. Scores on the HADS, PSS, and dysfunctional coping dimension of the Brief COPE Inventory were significantly higher, and RSES scores were significantly lower, in the PIU group. Logistic regression analysis indicated that PIU in patients was significantly associated with scores on the PSS and dysfunctional coping dimension of the Brief COPE Inventory.</P> <P><B>Conclusions</B></P> <P>Patients with schizophrenia spectrum disorders and PIU were significantly more likely to have high levels of perceived stress and dysfunctional coping strategies. Patients with schizophrenia spectrum disorders who also engage in PIU may benefit from interventions that help them to develop appropriate skills for coping with stress.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Patients with schizophrenia spectrum disorders showed a high prevalence (22.0%) of problematic internet use (PIU). </LI> <LI> High levels of perceived stress rather than psychopathology itself contributes to the development of PIU in stabilized patients with schizophrenia. </LI> <LI> Our results indicate that managing stress and developing coping strategies are important for the prevention of PIU among this group of patients. </LI> </UL> </P>

간승격(肝勝格) 혈위(穴位)에 시술된 침자(鍼刺)와 침습(侵襲) 및 비침습(非侵襲) 레이저 침요법(鍼療法)이 간손상(肝損傷) 회복에 미치는 영향

신형진 ( Hyung Jin Shin ),김영선 ( Young Sun Kim ),윤대환 ( Dae Hwan Youn ),이석희 ( Suk Hee Lee ),오광환 ( Gwang Hwan Oh ),정성호 ( Sung Ho Jeong ),나창수 ( Chang Su Na ) 대한경락경혈학회 2010 Korean Journal of Acupuncture Vol.27 No.1

Objective: This study was performed to investigate the effect of manual acupuncture, invasive laser acupuncture and laser skin irradiation at LU8, LR4, HT8 and LR2(Liver Seunggyeok) on D-galN-induced liver injury in rats. Method: Liver injury was induced with D-galN. The experimental rats were divided four groups(Control group, EXP-1, EXP-2, EXP-3). In the Control group, liver injury-induced and not treated. EXP-1 group was liver injury-induced and carried out manual acupuncture with Young-Su(against the meridian course and following the course of the meridian) & Won-Bang(by twisting and rotating the needle) acupuncture method at Liver Seunggyeok. EXP-2 group was liver injury-induced and carried out invasive laser acupuncture at Liver Seunggyeok. EXP-3 group was liver injury-induced and carried out laser skin irradiation at Liver Seunggyeok. Result: In the change of body weight(in 1 week), EXP-1, EXP-2 and EXP-3 groups were significantly increased as compared with control group. In the change AST & ALT, EXP-1 and EXP-2 groups were significantly decreased as compared with control group. In the change of SOD, EXP-1, EXP-2 and EXP-3 groups were significantly increased as compared with control group. In the change of WBC, EXP-2 group was significantly increased as compared with control group. Conclusion: Manual acupuncture, invasive laser acupuncture and laser skin irradiation at Liver Seunggyeok had hepatotherapeutic effect on the treatment of hepatocytotoxity. Invasive laser acupuncture was as effective as manual acupuncture on the treatment of hepatocytotocity.

Effect of gel spinning accompanied with cross-linking using boric acid on the structure and properties of high-molecular-weight poly(vinyl alcohol) fiber

Jo, Yong Gu,Shin, Eun Joo,Lee, Young Jae,Yoon, Won Sik,Han, Sung Soo,Lee, Yang Hun,Lee, Yong Rok,Noh, Seok Kyun,Gal, Yeong Soon,Lyoo, Won Seok Wiley Subscription Services, Inc., A Wiley Company 2009 Journal of applied polymer science Vol.113 No.3

<P>To enhance the thermal stability of poly(vinyl alcohol) (PVA) fiber, the fiber was prepared from the gel spinning of high molecular weight (HMW) PVA by using dimethyl sulfoxide/water (8/2, v/v) as a solvent, accompanied with the cross-link by boric acid (B-PVA). In addition, the structure and properties of the B-PVA fiber were compared with those of the HMW PVA fiber obtained by using the same spinning system without cross-linking (NB-PVA). Through a series of experiments, it turned out that cross-linking actualized by an optimum amount of boric acid (0.3 wt % based on PVA) and zone drawing caused significant changes in the properties of HMW PVA gel fiber. That is, cross-linking increased thermal degradation temperatures at each degradation step and amounts of final residues, resulting in improving thermal properties of the PVA fiber. On the contrary, it was found that in the case of the B-PVA fiber, some broadening of the original PVA unit cell occurred, which was identified by the peak shift to lower angle in X-ray diffractogram. The tensile strength and Young's modulus of B-PVA fiber with draw ratio of 15 are 23.1 and 308.3 g/d, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009</P>

Long Term Success Rate of Abstinence in the Elderly After Admission to Intensive Smoking Cessation Camp

( Jaekyeong Lee ),( Yu-il Kim ),( Ha-young Park ),( In-jae Oh ),( Tae-ok Kim ),( Hong-joon Shin ),( Yong-soo Kwon ),( Sung-chul Lim ),( Sun-seog Kweon ),( Hyungjoo Oh ) 대한결핵 및 호흡기학회 2020 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.128 No.-

Backgrounds Cigarette smoking is a major cause of lung cancer and COPD. Smoking cessation should be recommended at any age to prevent disease. But a question can be raised if recommendation to stop smoking in elderly is equally effective compared with non-elderly people. Because myth like stereotype exists about elderly people that they are prone to think they have lived long enough so that they don't try to put any effort to change their old habit. In this study, we will find if the abstinence rates are significantly different between non-elderly(< 65) and elderly( >=65) age group. Methods Current smokers had participated in intensive smoking cessation camp at Chonnam national university hospital between 2015 and 2017. We performed a retrospective study to figure out the differences of abstinence success rate between elderly and non-elderly groups. We followed up patients at 6 months from start of abstinence and 2019 year for long term follow-up. Logistic regression analysis was done to figure out which factors were associated with long term success rate of smoking cessation including age group, comorbidities, CO value, regular exercise which were statistically significant in chi-square test or standard t-test. Results Total 351 patients were enrolled. 51 of 81 (62.9%) patients in elderly and 74 of 181 (40.8%) in non-elderly were successful in maintaining abstinence at the time of long term follow up. Age group was not statistically significant in logistic regression analysis (p = 0.07, 95% CI = 0.956 - 3.205). 6 month abstinence was statistically significant in long-term success of abstinence (p = 0.003, 95% CI = 1.311 - 3.910). Conclusion There was no inferior result of abstinence success in the elderly. We can suggest elderly smokers quit their old habit because they are as eager as young-aged people to change.

일 도시지역 사업장내 인터넷 중독과 직무스트레스에 관한 연구

김남석(Nam-Seok Kim),신상은(Sang-Eun Shin),이계성(Kye-Sung Lee),이명지(Myung-Ji Lee),장은영(Eun-Young Jang) 한국중독정신의학회 2007 중독정신의학 Vol.11 No.2

Objectives:This study examined the prevalence of internet addiction, job stress, and psychopathology among industrial workers in Incheon, Korea. Methods:The subjects were male industrial workers (n=139) in Incheon, Korea. A self-rating questionnaire, asking about demographic data and including Young’s Internet addiction Test (IAT), the short form of the Korean Occupational Stress Scale (KOSS-SF) for job stress, and the Symptom Checklist-90-Revision (SCL-90-R), was administered in August 2006. Results:In this study, 12 subjects (8.6%) were in the internet addiction group and 128 subjects (91.4%) were in the non-addiction group. On the KOSS-SF, the internet addiction group scored higher for job stress than the internet non-addiction group, although the difference was not statistically significant. On the job stress subscales, relation conflict and workplace culture were significantly higher in the internet addiction group. The internet addiction group had higher scores on all symptom scales of the SCL-90-R. Paranoia was the psychopathology mediating the relation conflict between job stress and internet addiction. Conclusion:On the job stress subscales, relation conflict and workplace culture scored significantly higher in the internet addiction group than in the internet non-addiction group. The internet addiction group showed more severe psychopathology. Using the mediational relation model, we confirmed that the psychopathology of the SCL-90-R mediating job stress and internet addiction was paranoia. For more details, a future study is needed.

Meta-aramid 나노섬유의 전기방사 공정인자들이 물성과 투습성에 미치는 영향

박영신,남영식,이민성,박원호,Park, Young Shin,Nam, Young Sik,Lee, Min Sung,Park, Won Ho 한국섬유공학회 2012 한국섬유공학회지 Vol.49 No.4

Meta-aramid nanofibers were prepared by the electrospinning process. In this study, electrospun meta-aramid nanofiber webs were prepared with various velocity ratios of a collector drum, the fiber diameter and thickness of electrospun nanofiber webs, and then compared with values of tensile properties and breathable water-resistance. The meta-aramid nanofiber webs were analyzed by field-emission scanning electron microscopy, a tensile tester, water vapor permeability, an X-ray diffractometer and thermogravimetric analysis. The diameter of meta-aramid nanofibers ranging from 165 to 252 nm was obtained by electospinning. The tenacity, young's modulus and crystallinity of meta-aramid webs were decreased by increasing the diameter of meta-aramid nanofibers, however, water vapor permeability increased. It was confirmed that the breathable water-resistance of meta-aramid nanofiber webs were similar to that of chemical treated PTFE film.

디스패칭 룰 기반의 시뮬레이션 모델을 활용한 S-PMS 설계

이재용(Jae-yong Lee),김상태(Sang-tae Kim),박선영(Seon-young Park),신문수(Moonsoo Shin1),조용주(Yongju Cho) 한국산업경영시스템학회 2015 한국산업경영시스템학회 학술대회 Vol.2015 No.추계

The up-to-date small and medium-sized enterprises (SMEs) in Korea have tried to respond flexibly and rapidly to dynamic business environment and to establish efficient production management system based on information technologies. However, most of SMEs have faced with low applicability of the production management system resulting from high costs of introduction and maintenance. In this paper, a production planning and control system, that is S-PMS (production management system for SMEs), is proposed to solve the problem of low applicability and limited human resources. S-PMS enables production managers to efficiently collect and manage master data with the actual target production systems and explores the bottleneck process by means of simulation techniques to improve productivity. Furthermore, it implements rescheduling mechanism in terms of a variety of process routes. In essence, intuitive dispatching rules and integrated data management of S-PMS improve field applicability of production management system. Consequently, S-PMS is expected to be used as an efficient production management system of SMEs in Korea.