• Title/Summary/Keyword: Stress Function

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Epigenetic control of LTR retrotransposons in plant germline and somatic cells

  • Lee, Seung Cho;Parent, Jean-Sebastien;Ernst, Evan;Berger, Frederic;Grimanelli, Daniel;Martienssen, Robert A.
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.97-97
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    • 2017
  • Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

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The effect of behavioral and emotional change on usage mode and response-delay situation (사용 모드에 따른 반응지연 상황의 행동적, 정서적 효과)

  • Joo, Hyo-Min;Kim, Hyo-Sun;Kim, Hye-Ryeong;Han, Kwang-Hee
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.129-146
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    • 2010
  • System response times(SRTs) are getting important while increasing the function of system. In the past, most research studied SRTs on situation of computer usage. There are lacking the research on simple domain. This study focuses on behavioral and emotional effect on situation of cell phone usage(experience 1; independent variables: degree of SRTs, dependent variables: behavioral and emotional evaluation). And this study investigates the behavioral and emotional effect in same SRTs on different situation(experience 2; independent variables: degree of SRTs, usage mode, dependent variables: behavioral and emotional evaluation, stress, mental strain). The result indicated that long SRTs increased problem solving time and negative emotion. User evaluated the system differently according to usage mode after they performed the same task. In other word, if user had a strong goal, then they felt more negative emotion and mental effort than the user don't have a strong goal. In the goal mode group, it was important there are being of delay or not. This study demonstrated that SRTs and usage mode influence user's emotion and behavior performance in same task.

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A study on Crack Healing of Various Glassy Polymers (part I) -theoretical modeling- (유리질 중합체의 균열 Healing에 관한 연구 (제1보) -이론 모델링-)

  • Lee, Ouk-Sub
    • Journal of the Korean Society for Precision Engineering
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    • v.3 no.1
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    • pp.40-49
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    • 1986
  • Crack, craze and void are common defects which may be found in the bulk of polymeric materials such as either themoplastics or thermosets. The healing phenomena, autohesion, of these defects are known to be a intrinsic material property of various polymeric materials. However, only a few experimental and theoretical investigations on crack, void and craze healing phenomena for various polymeric materials have been reported up to date [1, 2, 3]. This may be partly due to the complications of healing processes and lacking of appropriate theoretical developments. Recently, some investigators have been urged to study the healing phenomena of various polymenic materials since the significance of the use of polymer based alloys or composites has been raised in terms of specific strength and energy saving. In the earlier published reports [1, 2, 3, 4], the crack and void healing velocity, healing toughness and some other healing mechanical and physical properties were measured experimentally and compared with predicted values by utilizing a simple model such as the reptation model under some resonable assumptions. It seems, however, that the general acceptance of the proposed modeling analyses is yet open question. The crack healing processes seem to be complicate and highly dependent on the state of virgin material in terms of mechanical and physical properties. Furthermore, it is also strongly dependent on the histories of crack, craze and void development including fracture suface morphology, the shape of void and the degree of disentanglement of fibril in the craze. The rate of crack healing may be a function of environmental factors such as healing temperature, time and pressure which gives different contact configurations between two separated surfaces. It seems to be reasonable to assume that the crack healing processes may be divided in several distinguished steps like stress relaxation with molecular chain arrangement, surface contact (wetting), inter- diffusion process and com;oete healing (to obtain the original strength). In this context, it is likely that we no longer have to accept the limitation of cumulative damage theories and fatigue life if it is probable to remove the defects such as crack, craze and void and to restore the original strength of polymers or polymer based compowites by suitable choice of healing histories and methods. In this paper, we wish to present a very simple and intuitive theoretical model for the prediction of healed fracture toughness of cracked or defective polymeric components. The central idea of this investigation, thus, may be the modeling of behavior of chain molecules under healing conditions including the effects of chain scission on the healing processes. The validity of this proposed model will be studied by making comparisons between theoretically predicted values and experimentally determined results in near future and will be reported elsewhere.

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A Study on the Characteristics of High-Tension Bolted Joints' Behavior due to Surface Condition (표면상태에 따른 고장력볼트 마찰이음부의 거동특성에 관한 연구)

  • Cho, Sun Kyu;Hong, Sung Wook
    • Journal of Korean Society of Steel Construction
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    • v.9 no.3 s.32
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    • pp.421-430
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    • 1997
  • In this study, the static and the fatigue tests were performed with high tension bolted joints, of which the surfaces were spread with inorganic zinc-primer after shot-blast, and milling surface, and steel-natural surface, difference of friction surface condition were examined by comparing the esults of tests. From the result of synthetical investigation of this study. it is proper that using the torque management method in order to introduce design axial force to blots, and the provision of specifications that initial axial forces must be 110% of design axial forces is proper. Decreasing ratio of axial forces to initial force is proportional to common lorgarithms of time progress, it converge constant value after 20 hours, and decreasing ratio is little related to the roughness of friction surface. Sliding coefficient of milling, spreading inorganic zinc-primer, just producting is great in order and sliding forces are dependent on the applied axial forces, but if the applied axial forces are great, sliding coefficient become small by a loss of roughness. So it is confirmed that relation between the applied axial forces and the sliding forces are not proportional linearly. From the result of estimation on fatigue strength, all specimens satisfy the specifications with B-grade and milling surface is lower than the others about 14% in fatigue strength because in milling surface lose the function of friction-types joints at lower number of cycles. From the result of eximination for the distribution area of compressive force, friction area near to inside bolt is wider in the direction of stress than near to outside. It is guessed that this situation occurs because outside bolts firstly change from the friction connection to the bearing connection.

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A Study on Architecture of Test Program based UML (UML 기반 점검 프로그램 설계 방법에 관한 연구)

  • Kim, ByoungYong;Jang, JungSu;Ban, ChangBong;Lee, HyoJong;Yang, SeungYul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.10
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    • pp.217-230
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    • 2012
  • This paper propose interacting test programming methods between test equipment and hardware unit to verify function and performance of the hardware unit under test. Proposed test program can minimizes the risk of failures when the unit is mounted on the aircraft by testing and verifying the unit under the worst stress condition. Also, Object oriented design using UML make it easy to apply in other equipments. Test program consists of architecture package and hardware package. Architecture package is in a role for system management, log analysis, message receiving and message analysis. Messages that are used by system management define messages for testing and defined messages is sent and received to test equipment through Ethernet. Hardware package is in a role for hardware management that is needed to be tested and is related to a system. Hardware to be tested is divided into internal test and transmission test. Internal test inspects hardware itself and reports the test results to the test equipment. Transmission test inspects communication device by sending or receiving data. All kinds of test is done in the worst condition of the test unit executing in parallel. Each device is tested at least 482 times and at most 15,003 times about one hour. Test program is utilized in hardware reliability test like as environmental test or EMI test.

Fracture Analysis of Implant Components using Scanning Electron Microscope : Part II - Implant Retaining Screw (임플란트 구성요소의 파절면에 관한 주사전자현미경적 연구 : Part II - 임플란트 유지나사)

  • Lim, Kwang-Gil;Kim, Dae-Gon;Cho, Lee-Ra;Park, Chan-Jin
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.4
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    • pp.373-388
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    • 2010
  • Fracture causes serious problems in many instance of prosthetic failures. But it is hard to find the definite causes when fractures occur. Fractography encompasses the examination of fracture surfaces that contain features resulting from the interaction of the advancing crack with the microstructure of the material and the stress fields. All fractured specimens(implant retaining screw) retrieved from Gangneung-Wonju national university dental hospital for 3 years(from 2007 to 2009). After pretreatment of samples, the scanning electon microscope were used for surface examination and fracture analysis. In case of most of the fractured specimens, fracture took place by fatigue fracture and fractured surface represents fatigue striation. Fatigue striation indicate the progression of the crack front under cyclic loading, are characteristic of stage 2 crack growth. The site of crack initiation and stage 1 crack growth were not easily identified in any of the failure, presumably because of the complex microstructural features of the polycrystalline sample. In case of fractured by overload, dimpled or cleavage surface were observed. Using the interpretation of characteristic markings(ratchet mark, fatigue striation, dimple, cleavage et al) in fracture surfaces, failure events containing the crack origin, crack propagation, material deficiency could be understand. Using the interpretation of characteristic markings in fracture surfaces, cause and mechanism of fractures could be analyzed.

Seminal Plasma Heparin Binding Proteins Improve Semen Quality by Reducing Oxidative Stress during Cryopreservation of Cattle Bull Semen

  • Patel, Maulikkumar;Gandotra, Vinod K.;Cheema, Ranjna S.;Bansal, Amrit K.;Kumar, Ajeet
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.9
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    • pp.1247-1255
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    • 2016
  • Heparin binding proteins (HBPs) are produced by accessory glands. These are secreted into the seminal fluid, bind to the spermatozoa at the time of ejaculation, favour capacitation, acrosome reaction, and alter the immune system response toward the sperm. The present study was conducted with an objective to assess the effect of purified seminal plasma-HBPs (SP-HBPs) on cross bred cattle bull sperm attributes during two phases of cryopreservation: Pre freezing and freezing-thawing. SP-HBPs were purified from pooled seminal plasma by heparin affinity chromatography. Three doses of SP-HBPs i.e. 10, 20, $40{\mu}g/mLs$ semen were standardized to find out the optimum dose and $20{\mu}g/mLs$ was found to be an optimum dose. Semen as such and treated with SP-HBPs was diluted with sodium citrate-egg yolk diluter and cryopreserved as per the standard protocol. Sperm parameters i.e. motility, viability, Hypo-osmotic swelling test (HOST), acrosome damage, in vitro capacitation and lipid peroxidation were evaluated in SP-HBP treated and untreated (control) semen at both phases of cryopreservation. A considerable variation in percent sperm motility, viability, membrane integrity (HOST), acrosome damage, acrosome reaction and lipid peroxidation was observed at both phases among the bulls irrespective of the treatment. Incubation of neat semen with $20{\mu}g/mL$ SP-HBP before processing for cryopreservation enhanced the average motility, viability, membrane integrity by 7.2%, 1.5%, 7.9%, and 5.6%, 6.6%, 7.4% in pre-frozen and frozen-thawed semen in comparison to control. There was also an average increase of 4.1%/3.9% in in vitro capacitation and acrosome reaction in SP-HBPs-treated frozen-thawed semen as compared to control. However, binding of SP-HBPs to the sperm declined acrosome damage and lipid peroxidation by 1.3%/4.1% and 22.1/$32.7{\mu}M$/$10^9$ spermatozoa in SP-HBP treated pre-frozen/frozen-thawed semen as compared to control, respectively. Significant (p<0.05) effects were observed only in motility, HOST and in vitro acrosome reaction. It can be concluded that treatment of neat semen with SP-HBPs before cryopreservation minimized the cryoinjury by decreasing the generation of reactive oxygen species.

Clinical Study of the effect of Ear Acupuncture on 102 Alcoholics (금주환자(禁酒患者) 102명(名)에 대(對)한 임상적(臨床的) 고찰(考察) (강원도지역(江原道地域)을 중심으로))

  • Kang, Jae-Chun
    • The Journal of Korean Medicine
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    • v.17 no.2 s.32
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    • pp.318-330
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    • 1996
  • We had been investigated the effect of ear acupuncture in alcoholics, but in Kang won do province never we have been investigated. so then in Sangji university oriental hospital from Mar. 1. 1995 to Feb. 28. 1996. we clinically analized 102 alcoholics treated The results were summarized as follow: 1. In Age distribution, 40s were the top as 28.4% and next 30s, 50s, 60s 70s, below 3Os. In Sex distribution, these were 92 person in male, 10 person in female. 2. Marrige Status revealed in descending order ; married, single, divorced Sibling order distribution in descending order; eldest son, middle son, youngest son, only son 3. Distribution of education in descending order ; high school, middle school, primary school, collage and graduate school, illiterate 4. Distribution of occupation in descending order; farmer, labor, merchent, salaried and inoccupation, service 5. Distribution of religion in descending order ; none, buddism, protestantism, catholicism 6. Distribution of family history of alcoholism; yes(24.5%), no(69.6%) 7. Distribution of onset of drinking in descending order ; 20s, below 20s, 30s and 40s, 50s 8. Distribution of duration of drinking in descending order ; 20-29 years, 10-19 and below years, 40-49 years, 30-39 years 9. Distribution of the reason of drinking in descending order ; habbit, business and reduce of stress, no reason, syndrome of stop drinking 10. Distribution of frequency of drinking in descending order ; daily, four or five times a week, irregularly, once a week, two or three times a week 11. Distribution of amount of drinking in descending order ; two bottles, one bottle, three bottles, half, bottle above four bottles 12. Distribution of Chief Complaint of Alcohol in descending order ; no appetite and anorexia, diarrhrea insomnia, fatigue, vomitting, tremor, drinking water, hallucination, abdominal pain, constipation 13. Distribution of total MAST score in descending order ; 26-48 score, 13-18 score, 19-25 score, 8-12 score, 0-7 score 14. In the treatment effects according to MAST score, these were complete stop drinking 18.0%, improved 53.0%, unchanged 29.0%. 15. Distribution of liver function test and treatment effects in descending order ; ALAT, ASAT, GGTP, Trigliceride, Alk-phosphatase and Total bilirubin The treatment effects in ear acupuncture were 70.5% effective ones ; stop drinking 17.6%, improved 52.9%. 17. These were headache, nausea, vomitting sense, weakness in revealing symtoms after treatment, but no severe side effect. 18. Distribution of the times of onset in the change of taste in descending order; 3-5 times, below 2 times and above 6 times.

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Molecular analysis of alternative transcripts of equine AXL receptor tyrosine kinase gene

  • Park, Jeong-Woong;Song, Ki-Duk;Kim, Nam Young;Choi, Jae-Young;Hong, Seul A;Oh, Jin Hyeog;Kim, Si Won;Lee, Jeong Hyo;Park, Tae Sub;Kim, Jin-Kyoo;Kim, Jong Geun;Cho, Byung-Wook
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.10
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    • pp.1471-1477
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    • 2017
  • Objective: Since athletic performance is a most importance trait in horses, most research focused on physiological and physical studies of horse athletic abilities. In contrast, the molecular analysis as well as the regulatory pathway studies remain insufficient for evaluation and prediction of horse athletic abilities. In our previous study, we identified AXL receptor tyrosine kinase (AXL) gene which was expressed as alternative spliced isoforms in skeletal muscle during exercise. In the present study, we validated two AXL alternative splicing transcripts (named as AXLa for long form and AXLb for short form) in equine skeletal muscle to gain insight(s) into the role of each alternative transcript during exercise. Methods: We validated two isoforms of AXL transcripts in horse tissues by reverse transcriptase polymerase chain reaction (RT-PCR), and then cloned the transcripts to confirm the alternative locus and its sequences. Additionally, we examined the expression patterns of AXLa and AXLb transcripts in horse tissues by quantitative RT-PCR (qRT-PCR). Results: Both of AXLa and AXLb transcripts were expressed in horse skeletal muscle and the expression levels were significantly increased after exercise. The sequencing analysis showed that there was an alternative splicing event at exon 11 between AXLa and AXLb transcripts. 3-dimentional (3D) prediction of the alternative protein structures revealed that the structural distance of the connective region between fibronectin type 3 (FN3) and immunoglobin (Ig) domain was different between two alternative isoforms. Conclusion: It is assumed that the expression patterns of AXLa and AXLb transcripts would be involved in regulation of exercise-induced stress in horse muscle possibly through an $NF-{\kappa}B$ signaling pathway. Further study is necessary to uncover biological function(s) and significance of the alternative splicing isoforms in race horse skeletal muscle.

Phellinus linteus; Market and Technology Trends Analysis (상황버섯의 기술개발 동향과 시장분석)

  • Sohn, Eun-Hwa;Roh, Hyun-Sook;Park, Young-Seo;Sohn, Eun-Soo;Kang, Se-Chan;Kang, Nam-Sung;Pyo, Suhk-Neung
    • KSBB Journal
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    • v.23 no.2
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    • pp.109-117
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    • 2008
  • Phellinus linteus (Sang Hwang mushroom; P. linteusis) has been widely used for a traditional medicine in Japan, Korea and China. In traditional oriental applications, P. linteus and their extracts have been exclusively used to treat various diseases like insomnia, neurasthenia, gastric ulcers, arthritis, nephritis, stress, asthma, bronchitis, neuromuscular disorders, hypertension and also as an immune system stimulator in cancer therapy. In a number of articles, it is indicated how tremendous their therapeutic values are. According to these studies, P. linteus and their extracts show immunomodulatory activities like enhancing immune system function including anti-tumor activity and inhibiting the growth of existing tumors. P. linteus and their extracts have been being studied for use as immunotherapy agents and biological response modifiers (BRMs) for the possible treatment of cancer without side effects. Recently, the cultured mycelium product of P. linteus has been developed and approved as a medicine in Korea. This review shows not only the current status of methods of developmental technology like artificial culture and various biological applications of P. linteus but also recent market trends of functional foods made from P. linteus.