• Title/Summary/Keyword: Self-reaction

Search Result 742, Processing Time 0.34 seconds

Dependence of Molecular Recognition for a Specific Cation on the Change of the Oxidation State of the Metal Catalyst Component in the Hydrogel Network

  • Basavaraja, Chitragara;Park, Do-Young;Choe, Young-Min;Park, Hyun-Tae;Zhao, Yan Shuang;Yamaguchi, Tomohiko;Huh, Do-Sung
    • Bulletin of the Korean Chemical Society
    • /
    • 제28권5호
    • /
    • pp.805-810
    • /
    • 2007
  • Molecular recognition for a specific cation depending on the change of the oxidation state of the metal catalyst component contained in the hydrogel network has been studied in a self-oscillating hydrogel. The selfoscillating hydrogels are synthesized by the copolymerization of N-isopropylacrylamide (NIPAAm), lead methacrylic acid (Pb(MAA)2), and Ru(bpy)3 2+ monomer as a metal catalyst component. The recognition for a specific cation (in this study, Ca2+ has been used) is characterized by the adsorbed amount of Ca2+ into the gel. The recognition of the gels for Ca2+ is higher at the temperature below the LCST, and also higher at the oxidized state than at reduced state of the metal catalyst component which corresponds to a more swollen state. Moreover, a propagating wave induced by a periodic change of the oxidation state with the diffusion phenomena in the oscillating hydrogel shows a possibility for temporal and site-specific molecular recognition due to the local swelling of the gel.

간호대학생의 심정지 시뮬레이션 실습 경험 (Nursing Student's Experiences on Simulation Practice focusing on Cardiac Arrest)

  • 송미숙;제경성
    • 문화기술의 융합
    • /
    • 제4권1호
    • /
    • pp.119-128
    • /
    • 2018
  • 본 연구는 간호대학생 4학년의 심정지 시뮬레이션 실습 경험을 알아보기 위한 질적연구이다. 참여자는 심정지 시뮬레이션 실습교육에 참여한 간호대학생 4학년 50명을 대상으로 하였다 연구기간은 2017년 12월 4일부터 12월 16일까지 진행하였다. 대상자의 심정지 시뮬레이션 실습경험을 탐구하기 위해 실습을 하고 난 후 자신의 경험을 서술식으로 자유롭게 작성하도록 한 성찰일지를 Braun과 Clarke의 주제 분석방법으로 분석하였다. 연구 결과 간호대학생의 심정지 시뮬레이션 실습 경험은 '시뮬레이션 수업유형에 대한 기대감', '아쉬움이 밀려옴', '미리 겪어보는 심정지 상황', '팀 상호작용의 중요성 인식', '적극적 대처', '간호학생에서 간호사로 역할이 확장됨'으로 나타났다. 결론적으로 간호대학생의 심정지 시뮬레이션 실습 경험을 이해하는 것은 심정지 시뮬레이션 실습교육을 효과적으로 운영하는데 필요한 기초자료로 활용될 수 있을 것이다.

희토류 원소의 분리를 위한 표면 개질 된 메조 다공성 실리케이트의 개발에 관한 연구 (Study on CMPO (Carbamoylphosphate) derivative functionalized ordered mesoporous silicates for selective removal of lanthanide)

  • 권법진;정현;김종영
    • 한국결정성장학회지
    • /
    • 제22권6호
    • /
    • pp.291-298
    • /
    • 2012
  • 자기 조립 분자 집합체 물질인 CMPO로 표면개질 된 메조 다공성 실리케이트를 가수분해와 축합반응을 이용하여 합성하였다. 손님 물질인 CMPO는 2-(diphenylphosphoryl) acetic acid와 3-(triethoxysilyl) propan-1-amine의 아마이드 결합반응을 이용하여 합성하였으며, MCM-41, SBA-15 그리고 실리카 나노입자와 같은 다양한 메조 다공성 실리케이트는 주인물질로 채택하였다. 메조 다공성 실리케이트의 비표면적은 680 $m^2/g$~1310 $m^2/g$의 넓이로 측정되었으며 BJH 방법을 이용해서 동공의 크기를 확인한 결과 2.3~9.1 nm 범위의 다양한 크기를 가지고 있었다. 메조 다공성 실리카 중에서는 SBA-15(II)가 가장 높은 약 35 wt%의 CMPO 함유량을 나타내었다. 메조 다공성 실리케이트의 표면에 개질된 CMPO 실란 작용기와 란탄족 이온과의 접근성에 관한 연구 결과, CMPO로 개질 된 모든 흡착제의 경우 상대적으로 이온 반경이 큰 La(III)보다는 크기가 작은 Nd(III)와 Eu(III) 이온을 더 선호하였다.

토론 및 자기 반성 과정을 통한 중학교 1학년 학생들의 탐구 문제 수정 과정에 대한 사례 분석 (A Case Study on the 7th Grade Students' Process of Revising Their Own Inquiry Problems in the Course of Group Discussion and Self Reflection)

  • 김재우;오원근
    • 한국과학교육학회지
    • /
    • 제22권2호
    • /
    • pp.267-275
    • /
    • 2002
  • 중학교 1학년 학생을 연구 대상으로 방학 중 수행하게 될 탐구 문제에 대하여 토론하도록 하였다. 탐구 문제가 어떻게 수정되고 비판받으며 보다 탐구 가능하게 되는지 3명의 학생을 사례 분석하였다. 학생들은 탐구 문제와 그 탐구 방법을 항상 관련지어 토론하였고 타당한 탐구 방법의 존재 여부는 탐구 문제를 폐기하도록 하는데 큰 영향을 주었다. 또한 탐구문제가 일상적인 것이 많았는데 그 일상성이 비판의 대상이 되기도 하였다. 탐구 문제 및 방법에 대한 비판에 대하여 학생들은 다양한 반응을 보여주었다. 비판에 대하여 자신의 의견을 수정하는 유형과 자기 의견을 끌까지 고수하는 유형으로 크게 나뉘어졌다.

Streptomyces mobaraensis로부터 생산되는 transglutaminase 분리 및 모델식품 적용 (The Separation of Transglutaminase Produced from Streptomyces mobaraensis and Its Application on Model Food System)

  • 유재수;신원선;전계택;김영수;정용섭
    • 한국식품과학회지
    • /
    • 제35권2호
    • /
    • pp.260-265
    • /
    • 2003
  • 본 연구에서는 수율과 protease 제거정도 그리고 분리정제 비용을 고려하여 암모늄 설페이트 침전과 Monoplus S100 수지로 처리한 효소를 밀가루에 적용하여 반죽 형성 시 물리적 특성개선 효과를 조사하였다. 암모늄설페이트 침전, 이온 교환수지, 겔 크로마토그래피를 통한 정제된 효소의 분자량은 SDS-PAGE상에서 38,000으로 판정되었고 단일밴드로 나타나 정제도가 높음을 알 수 있었다. Farinograph를 이용하여 측정한 밀가루 반죽의 특성변화에서 저항성의 지표가 되는 안정도는 대조구가 4분, 조효소는 대조구보다 짧은 3.5분, 정제된 효소는 대조구보다 길게 측정되었다. 반죽의 약화도는 조효소의 경우 대조구보다 높게 측정되었고, 정제된 효소의 경우 대조구보다 낮은 값을 나타냈다. 이 결과로부터 조효소의 경우 protease 존재로 인하여 반죽의 분해가 진행됨을 알 수 있었고, 정제된 효소 첨가로 인하여 물성이 향상됨을 알 수 있었다. 대조군의 밀가루 반죽의 valorimeter 값은 52로 측정되었고, 정제된 효소첨가에 의해 증가되었다. S. mobaraensis가 분비하는 transglutaminase의 정제단계를 조절하고 최적화 시킬 경우 국내산 밀가루의 반죽특성의 효과를 기대할 수 있다고 판단된다.

Role of Glyco-Persica® in Targeting Diabetes Type 2: an Integrative Approach

  • Dashtdar, Mehrab;Dashtdar, Mohammad Reza;Dashtdar, Babak;Khan, Saeed Ahmad
    • 대한약침학회지
    • /
    • 제16권4호
    • /
    • pp.14-21
    • /
    • 2013
  • Objectives: The objective of this study was to examine how an integrated approach to type 2 diabetes mellitus treatment could improve glycemic control and immune-potentiating activities adherent to oral hypoglycemic agents along with a botanical compound, among primary care patients. Methods: In this study, we used the self-control and the group-control methods. Candidates meeting the trial conditions were selected from among volunteers who had taken the test substance for 45 days. During the trial, all groups were on a controlled diet; neither were the original medications nor their dosages changed. Results: The results showed that the botanical compound (Glyco-Persica$^{(R)}$) significantly reduced the main clinical symptoms in diabetes type 2. In the treatment group, 36 of 52 patients (69.23%) and in the control group 10 of 52 patients (19.23%) showed reduced symptoms, and this difference was statistically significant (P < 0.05). The fasting blood sugar in the treatment group after treatment compared with that before treatment and with that in the control group after treatment was statistically different (P < 0.05). The post-prandial glucose in the treatment group after treatment was significantly different from that before treatment and from that in the control group after treatment (P < 0.05); the post-prandial blood sugar in the treatment group was reduced by 8.98%. Conclusions: The results revealed that the botanical compound (Glyco-Persica$^{(R)}$) has significant hypoglycemic properties which affect main clinical symptoms in diabetes type 2. Body weight, blood pressure, heart rate, routine blood, stool and urine tests showed no meaningful negative changes after the course of treatment. There was no significant adverse reaction during the trial.

Functional Modification of a Specific RNA with Targeted Trans-Splicing

  • Park, Young-Hee;Kim, Sung-Chun;Kwon, Byung-Su;Jung, Heung-Su;Kim, Kuchan;Lee, Seong-Wook
    • Genomics & Informatics
    • /
    • 제2권1호
    • /
    • pp.45-52
    • /
    • 2004
  • The self-splicing group I intron from Tetrahymena thermophila has been demonstrated to perform splicing reaction with its substrate RNA in the trans configuration. In this study, we explored the potential use of the trans-splicing group I ribozymes to replace a specific RNA with a new RNA that exerts any new function we want to introduce. We have chosen thymidine phosphorylase (TP) RNA as a target RNA that is known as a valid cancer prognostic factor. Cancer-specific expression of TP RNA was first evaluated with RT-PCR analysis of RNA from patients with gastric cancer. We determined next which regions of the TP RNA are accessible to ribozymes by employing an RNA mapping strategy, and found that the leader sequences upstream of the AUG start codon appeared to be particularly accessible. A specific ribozyme recognizing the most accessible sequence in the TP RNA with firefly luciferase transcript as a 3' exon was then developed. The specific trans-splicing ribozyme transferred an intended 3' exon tag sequence onto the targeted TP transcripts, resulting in a more than two fold induction of the reporter activity in the presence of TP RNA in mammalian cells, compared to the absence of the target RNA. These results suggest that the Tetrahymena ribozyme can be a potent anti-cancer agent to modify TP RNAs in tumors with a new RNA harboring anti-cancer activity.

Poling Field Effect on Absorption and Luminescence of Disperse Red-19 and TiO2 Composites

  • Kim, Byoung-Ju;Hwang, Un-Jei;Jo, Dong-Hyun;Lim, Sae-Han;Kang, Kwang-Sun
    • Current Photovoltaic Research
    • /
    • 제3권1호
    • /
    • pp.5-9
    • /
    • 2015
  • Absorption and luminescence characteristics of disperse red-19 (DR-19) and $TiO_2$ composite have been investigated with various poling electric field strengths. Two step synthetic processes were employed to employ the DR-19 to the $TiO_2$ sol-gel. Firstly, urethane bond formation between DR-19 (-OH) and 3-isocyanatopropyl triethoxysilane (ICPTES, -N=C=O) performed (ICPDR) prior incorporation to the $TiO_2$ sol-gel. Secondary, the hydrolysis of the ethoxy group from the ICPTES and condensation reaction between silanol groups from ICPTES and $TiO_2$ sol-gel were performed. The ICPDR and $TiO_2$ sol-gel ($DRTiO_2$) were mixed and stirred for several days. The composite was coated to the ITO coated glass substrate. Corona poling were performed before drying the composite with various electric field strengths. The absorption intensity decreased with the increase of the poling field strength, which resulted in the increase of poling efficiency. The photoluminescence also decreased as the poling field strength increased. There is long luminescence tail for the poled $DRTiO_2$ film compared with unpoled $DRTiO_2$ film. The luminescence long tail indicates that the self-trapped excitons and polarons were generated when the $DRTiO_2$ film was poled with electric field.

스토리텔링을 활용한 '태양계와 별' 단원 수업이 과학개념 및 과학학습 동기에 미치는 효과 (The Effects of 'Solar System and Star' Using Storytelling on Science Concept and Science Learning Motivation)

  • 김윤경;이용섭
    • 대한지구과학교육학회지
    • /
    • 제9권1호
    • /
    • pp.97-105
    • /
    • 2016
  • The purpose of this study was to examine the effects of storytelling skill on science concept and science learning motivation. For this study the 5 grade, 2 class was divided into a research group and a comparative group. The class was pre-tested in order to ensure the same standard. The research group had the science class with storytelling skill, and the comparative group had the class of the teacher centered lectures on 11 classes in 8 weeks. The storytelling skill was focused on set the astronomical target wants to set up a story, through the small group discussion, present subject of the story, set the protagonist of the story for smooth configuration of the story, in order to smooth the flow of the story, make up a story around a hero, to make a clear story, decorated with pictures, shapes, graphs, etc, group story, complete with an astronomical(saints) in storytelling. To prove the effects of this study, science concept was split up according to knowledge, inquiry, attitude. Also, science learning motivation consisted of assignment is worth, learning beliefs about control, self efficacy. The results of this study are as follows. First, using storytelling skill was effective in science concept. Second, using storytelling skill was effective in science learning motivation. Also, after using storytelling skill was good reaction by students. As a result, the elementary science class with storytelling skill had the effects of developing science concept and science learning motivation. It means the science class with storytelling skill has potential possibilities and value to develop science concept and science learning motivation.

자기 통전식 SiC세라믹 발열체 개발을 위한 기초 특성 연구 (Study of Basic Properties to Develope SiC Ceramic Heater by Self-Charge with Electricity)

  • 신용덕;고태헌;주진영
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.124-125
    • /
    • 2007
  • The composites were fabricated $\beta$-SiC and $TiB_2$ powders with the liquid forming additives of 8, 12, 16[wt%] $Al_2O_3+Y_2O_3$ as a sintering aid by pressureless annealing at $1,650[^{\circ}C]$ for 4 hours. Reactions between SiC and transition metal $TiB_2$ were not observed in the microstructure and the phase analysis of the pressureless annealed SiC-$TiB_2$ electroconductive ceramic composites. The relative density, the flexural strength, the Young's modulus and the Vicker's hardness showed the highest value of 82.29[%], 189.5[MPa], 54.60 [GPa] and 2.84[GPa] for SiC-$TiB_2$ composites added with 16[wt%] $Al_2O_3+Y_2O_3$ additives at room temperature. The relative density of SiC-$TiB_2$ composites was lowered due to gaseous products of the result of reaction between SiC and $Al_2O_3+Y_2O_3$. The electrical resistivity showed the lowest value of 0.012[${\Omega}{\cdot}cm$] for 16[wt%] at 25[$^{\circ}C$]. The electrical resistivity was all negative temperature coefficient resistance (NTCR) in the temperature ranges from 25[$^{\circ}C$] to 700[$^{\circ}C$].

  • PDF