• Title/Summary/Keyword: 입체장애

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Chemical Reactions in Surfactant Solutions(Ⅲ). Nucleophilic and Micellar Catalyses on Hydrolysis of an Organic Phosphate by Sodium 2-Alkylbenzimidazole-5-sulfonates in Aqueous and CTABr Solutions (계면활성제 용액속에서의 화학반응(제3보) 유기인산 에스테르의 가수분해반응에 미치는 2-알킬벤즈이미다졸-5-술포네이트의 친핵적 및 미셀 촉매효과)

  • Hong, Yeong Seok;Park, Hui Hyeon;Park, Han Seok
    • Journal of the Korean Chemical Society
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    • v.34 no.6
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    • pp.629-636
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    • 1990
  • Dephosphorylation of p-nitrophenyldiphenylphosphate(p-NPDPP) mediated by anions of sodium 2-alkylbenzimidazole-5-sulfonate(R-BI-SO$_3$Na) in CTABr micellar solutions are obviously slower than that by anion of sodium benzimidazole-5-sulfonate(BI-SO$_3$Na), and the reation rates were decreased with increase of lengths of alkyl groups. This presents a striking contrast to the reactions in aqueous solutions without added CTABr, of which the reaction rates are on approximately same levels. It seems due to steric effect of alkyl groups of R-BI$^-$SO$_3$Na in the Stern layer of micelle, and it is supported by measured activation parameters(△H$^\neq$/TEX>, △G$^\neq$/TEX> and △S$^\neq$/TEX>) of the reactions in aqueous and micellar solutions. In addition to nucleophilic ability of benzimidazole moiety of R-BI$^-$SO$_3$Na on the reactions, these compounds with long alkyl groups(nonyl to pentadecyl) are micellized for themseleves, and increase the reaction rates due to their micellar catalyses in aqueous solutions, not including CTABr.

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A Convergent Approach to Gain a Better Understanding of Alzheimer's Disease: Stereoscopic Vision (융복합적 접근을 통한 알츠하이머형 치매의 이해 증진 : 양안 지각)

  • Kim, Nam-Gyoon;Lee, Ho-Won
    • Journal of the Korea Convergence Society
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    • v.10 no.5
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    • pp.103-110
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    • 2019
  • The present study investigated the effects of AD on stereoscopic vision. Sixty participants (20 AD patients, 20 mild cognitive impairment patients, 20 healthy elderly controls) participated in the study. Two cubes, one on the left and the other on the right of the center of the monitor, appeared at varying distances from the observer with their relative distances controlled in two disparity conditions (absolute vs relative disparity) combined with two disparity directions (crossed vs uncrossed disparity). Participants identified the object that appeared closer to them. Results demonstrated comparable performance with all three groups performing accurately, suggesting that the effect of AD on stereopsis is negligible. Discussion focused on brain pathology affected by AD involving high level visual processing.

How does stereology help to inform translation from neuroscience to OT? (입체해석학을 통해 신경과학의 정보를 작업치료학에 어떻게 전달할수 있을까?)

  • Park, Ji-Hyuk;Lee, Joo-Hyun;Park, Jin-Hyuck
    • Therapeutic Science for Rehabilitation
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    • v.3 no.2
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    • pp.5-48
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    • 2014
  • Introduction : One of the important domains in OT is performance skills which include sensory perceptual skills, motor and praxis skills, emotional regulation skills, cognitive skills, and communication/social skills. All of these skills are support ed by integrated neurological processes. Body : Stereology robust tool when employed to investigate morphological changes in neurons, cortex area, and specific parts of brain involved in special brain function. Stereology is an interdisciplinary field focused or analyzing biological tissue with the three-dimensional interpretation of planer sections by using estimating method and mathematically unbiased sampling. With the unbiased stereological method based on probability theory, researchers can estimate morphological and anatomical changes in biological reference areas accurately and efficiently. Changes in anatomical and cytoarchitectural parameters, such as volume, number, and length, affect specific brain function related to the brain area. Occupational therapists provide treatment to improve functions for participation of occupation in neurological disorder. The functional improvements in neurological disorder reflect neurobiological changes because functional difficulties, such as motor cognitive disorder, are due to neurological disturbances. Thus, combination of two kinds of evidence, neurological changes and functional improvement, provide fundamental evidence for OT intervention in neurological disorder. Even though most of stereological studies are in animal model and in postmortem human because of practical and ethical issues, stereology provides fundamental knowledge to support OT theory and practice. Conclusion : Therefore, stereology informs translation from neuroscience to OT based on structure-function relationship in performance skills and experience-dependent neural plasticity.

요전완유리피판을 이용한 연구개 결손부 재건후 기능평가

  • 박해섭;김민식;선동일;유우정;김형태;박영학;조승호
    • Proceedings of the KSLP Conference
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    • 1998.11a
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    • pp.188-188
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    • 1998
  • 구강후부암은 흔히 연구개, 설근부 등을 침범하여 연구개의 절제가 동반되고 이에 따른 발성, 연하 등에 장애를 남기게 된다. 이의 재건을 위해 다양한 피판술이 고안되고 있으며 그 중 요전완유리피판은 피판이 얇고 유연하여 입체적 형태의 재건이 용이하며 감각신경을 포함하여 재건할 수 있고 장장근인대를 포함시킬 경우 연구개의 역동적인 기능까지 재건할 수 있는 등의 장점으로 최근 많이 이용되고 있다. (중략)

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A Study On Audial and Visual Information Transfer System for the disable and general Audience (시청각 장애관객 및 일반 관객을 위한 오디얼, 비주얼 정보 전달 시스템 연구)

  • Lee, Dong-Hun;Jang, Tae-Soo;Shin, Ho
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.756-762
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    • 2009
  • The interest of show industry as leisure and culture bring about quantitative increase of public facility. It indicate the effort of bring culture benefits to the disable and the general who want detail information. Especially, there is less technology and service to help them. So it is very necessary method which is using the audial and visual transfer technology to solve the limitation. This study aimed at indicating the method that applied the audial and visual transfer technology which are useful for both The disable and General Audience.

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Absorption Equilibrium of CO2 in the Sterical Hindered Amine, AMP Aqueous Solution (입체장애아민 AMP (2-amino 2-methyl 1-propanol) 수용액의 CO2 흡수평형)

  • Han, Keun-Hee;Lee, Jong-Seop;Min, Byoung-Moo
    • Korean Chemical Engineering Research
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    • v.45 no.2
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    • pp.197-202
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    • 2007
  • This research was basically carried out to extend the application of $CO_2$ absorption processes for flue-gas system, which are mainly applied to a reforming process in petro-chemical industries. In general, MEA absorbent has some problems in flue-gas treatment, such as, degradation, regeneration energy and absorption capacities. As we known, sterical hindered amine, typically AMP (2-amino 2-methyl 1-propanol), have a good potential to improve these problems. In this paper, the characteristics of $CO_2$ absorption in aqueous AMP solution were measured and compared with that of MEA. It has been found that the $CO_2$ absorption capacity in AMP is double than that of MEA in the low $CO_2$ partial pressure system such as flue-gas. Also, the equilibriums of $CO_2$-AMP system were partially suggested, which are essentially needed to design the absorption process.

Effects of tongue strength training program combined with oral exercises on swallowing disorder, swallowing ability, and tongue pressure in the elderly (입체조를 병행한 혀 근력운동이 노인의 연하장애와 연하력 및 설압에 미치는 효과)

  • Nam-Suk Kim;Jung-Hwa Lee
    • Journal of Korean society of Dental Hygiene
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    • v.23 no.2
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    • pp.105-113
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    • 2023
  • Objectives: The purpose of this study is to verify the usefulness and practicality of the program in the daily life of the elderly by performing a three-dimensional tongue muscle exercise for the elderly to identify the dysphagia, swallowing ability, and tongue pressure. Methods: The subjects of the study were 29 elderly people aged 65 or older living in Busan, divided into a oral exercises group and tongue strength training program combined with oral exercises group, and operated 16 times for 8 weeks twice a week, and the pre and post-program evaluation was conducted in the 1st and 8th weeks. For variable selection, 7 general characteristics, 5 oral health-related characteristics, 5 Likert scale for swallowing disorder, repetitive swallowing ability test for swallowing power measurement, and tongue pressure measurement was used. Data analysis was conducted using SPSS window program 25.0 version (IBM), general characteristics and homogeneity tests, oral health-related characteristics and homogeneity tests were chi-square test, swallowing disorder, swallowing ability, and change in tongue pressure were paired t-test, Wilcoxon signed rank test, t-test, Mann-Whitney U test for swallowing disorder and changes in swallowing ability and tongue pressure, and Spearman's correlation for the relationship between swallowing disorder and swallowing ability and tongue pressure. Results: As a result of tongue strength training program combined with oral exercise, both relieve swallowing disorder and improve low eating and tongue pressure than oral exercise, and the difference in improvement effects of both relieve swallowing disorder, swallowing ability, and tongue pressure is higher. Conclusions: Based on the results of this study, it is believed that simple and practical oral muscle function reinforcement products and practical use are needed, and institutional devices to seek oral health promotion programs for the elderly are needed.

Activation of Aromatic Carbon-Hydrogen Bonds by Palladium Trifluoroacetate Complexes (Pd(CF3CO2)2 착화합물 촉매에 의한 방향족 탄소-수소 결합의 활성화 반응)

  • Hwang, Yeong-Ae;Kim, Dong-Hwan;Baek, Du-Jong
    • Journal of the Korean Chemical Society
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    • v.50 no.5
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    • pp.369-373
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    • 2006
  • Arylation reactions of styrene catalyzed by Pd(CF3CO2)2-sulfides and Pd(CF3CO2)2-phosphines were investigated. The yield of trans-stilbene, the main product, increased as the basicity of the substituents on the aryl groups of the phosphines increased and the steric hindrance of the substituents decreased. The mechanism of the aryl migration of arylphosphines to styrene is proposed to involve the electrophilic attack of Pd to the phenyl group on the phosphines. The phosphine systems were found to be more effective than the sulfide ones.

Synthesis of Mannich Bases Using Substitued Aromatic Alcohols with Secondary Amines: Relative Reactivity and Regioselectivity Depending on Substrates (치환된 방향족 알코올과 이차아민을 사용한 Mannich염기의 합성:기질에 따른 상대적인 반응성과 위치선택성)

  • Chi, Ki Whan;Ahn, Yoon Soo;Park, Tae Ho;Ahn, Jeong Soo;Kim, Hyun Ah;Park, Joo Yeon
    • Journal of the Korean Chemical Society
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    • v.45 no.1
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    • pp.51-60
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    • 2001
  • One-pot Mannich reaction of substituted hydroxy aromatic compounds with secondary amines in an aprotic solvent has been studied. The results demonstrate that the relative reactivity and regioselectivity of the Mannich reaction depend on the steric hindrance of amines as well as the nucleophilicity of hydroxy aromatic rings.

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Thermal Properties and fracture Toughness of Difunctional Epoxy Resins Cured by Catalytic Initiators (촉매형 개시제로 경화된 이관능성 에폭시 수지의 열적 특성 및 파괴인성)

  • 박수진;허건영;이재락
    • Polymer(Korea)
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    • v.26 no.3
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    • pp.344-352
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    • 2002
  • In this work, two thermal cationic latent catalysts, i.e., triphenyl benzyl phosphonium hexafluoroantimonate (TBPH) and benzyl 2-methylpyrazinium hexafluoroantimonate (BMPH) were newly synthesized. And the thermal and mechanical properties of difunctional epoxy (diglycidylether of bisphenol h, DGEBA) resins initiated by 1 phr of either TBPH or BMPH catalyst were investigated. As experimental results, the epoxy/TBPH system showed higher curing temperature and critical stress intensity factor ($K_{IC}$) than those of epoxy/BMPH. This could be interpreted in terms of slow thermal diffusion rate and bulk structure of four phenyl groups in TBPH. However, the decomposed activation energy determined from Coats-Redfern method was lower in the case of epoxy/TBPH. This result was probably due to the fact that broken short chain structure was developed by steric hindrance of TBPH.