• 제목/요약/키워드: Long range dependent

검색결과 112건 처리시간 0.021초

사전압밀된 포화점토의 응력이력과 2차압밀에 관한 연구 (A Study on the Stress History and Secondary Compression of Saturated Clays Subjected to Precompression)

  • 김형주
    • 한국지반공학회지:지반
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    • 제10권4호
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    • pp.167-180
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    • 1994
  • 사전압밀된 포화점토의 응력이력이 2차압밀특성에 미치는 영향 및 Bjerrum모델이 과압밀점토의 2차압밀침하추정에 적용가능한지를 실험적으로 파악하기 위하여 재성형점토를 이용하여 재하-제하 및 재하-제하-재재하 응력이력의 조건에서 일련의 장기압밀시험을 실시하였다. 실험결과에 의하면 과압밀점토의 2차압밀침하는 전반부에서 응력이력의 영향을 받고 전반부의 2차압밀계수 Cn은 OCR(선행 압밀하중 Pcy재재하하중 Pr), 최대 OCR(선행압밀하중 Pcy제 하시의 하중 Pu)과,제하시간에 의존하며 과압밀비 증가에 따라 감소한다. 또한 2차압밀후반부 의 2차압밀계수 C.2는 OCR의 영향을 받으며 과압밀비 증가에 따라 감소한다. 최종적으로 실험 결과와 Bjerrum모델을 비교분석한 결과 임의 응력이력범위를 벗어나면 과압밀점토에서 Bjerrum모델의 적용은 가능하다.

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Odorant Stimulation Promotes Survival of Rodent Olfactory Receptor Neurons via PI3K/Akt Activation and Bcl-2 Expression

  • Kim, So Yeun;Yoo, Seung-Jun;Ronnett, Gabriele V;Kim, Eun-Kyoung;Moon, Cheil
    • Molecules and Cells
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    • 제38권6호
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    • pp.535-539
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    • 2015
  • Olfactory stimulation activates multiple signaling cascades in order to mediate activity-driven changes in gene expression that promote neuronal survival. To date, the mechanisms involved in activity-dependent olfactory neuronal survival have yet to be fully elucidated. In the current study, we observed that olfactory sensory stimulation, which caused neuronal activation, promoted activation of the phosphatidylinositol 3'-kinase (PI3K)/Akt pathway and the expression of Bcl-2, which were responsible for olfactory receptor neuron (ORN) survival. We demonstrated that Bcl-2 expression increased after odorant stimulation both in vivo and in vitro. We also showed that odorant stimulation activated Akt, and that Akt activation was completely blocked by incubation with both a PI3K inhibitor (LY294002) and Akt1 small interfering RNA. Moreover, blocking the PI3K/Akt pathway diminished the odorantinduced Bcl-2 expression, as well as the effects on odorant-induced ORN survival. A temporal difference was noted between the activation of Akt1 and the expression of Bcl-2 following odorant stimulation. Blocking the PI3K/Akt pathway did not affect ORN survival in the time range prior to the increase in Bcl-2 expression, implying that these two events, activation of the PI3K pathway and Bcl-2 induction, were tightly connected to promote post-translational ORN survival. Collectively, our results indicated that olfactory activity activated PI3K/Akt, induced Bcl-2, and promoted long term ORN survival as a result.

규칙적인 운동프로그램이 경로당 이용 노인의 건강에 미치는 효과 (The Effects of Excercise Program on Health of the Elderly in Senior Citizen's Center)

  • 최선하
    • 한국보건간호학회지
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    • 제11권2호
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    • pp.38-56
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    • 1997
  • A great deal of attention has been paid to the quality of life in citizens due to the increased number of long term life expectancy. reported as effective in the health promotion of the senior citizens. In this study, the principal investigator developed an exercise program for the senior citizens, which could be educated and managed by nursing staff. This kind approach may support the need of exercise program on regular base via the social organization, which may mean the intentional change of life style. The exercise program consisted of exercise, health education, and a direct the population of the senior A regularexercise has been nursing care. A quasi -experimental study was conducted to investigate the effects of excercise program on health of the elderly in senior citizen's center. Independent variable was a 9 weeks exercise program. Dependent variables were: 1) physical health [e.g. physical fitness(cardiopulmonary endurance, back muscle strength, grip strength, muscular tolerance, flexibility and body fat proportion), physiologic parameters(blood pressure, pulse, respiration. and blood glucose), and perceived physical health status; 2) mental health measured by depression score; and 3) cognitive perception of exercise measured by usefulness and self-efficacy. A total of 37 subjects was randomly assigned into either the control group (without the exercise program: n=18) or the intervention group(with the exercise program: n=19). The results of the study analyzed using a SAS, were as follows: 1) In physical fitness of physical health, there was a significant improvement in cardiopulmonary tolerance. back muscle strength. muscular tolerance and flexibility in the intervention group, compared to the control group, while no difference in grip strength and body fat proportion. The exercise program resulted in decreases in blood pressure, pulse, respiration and blood glucose within normal range and improvement of perceived physical health status in the intervention group. 2) There was a slight increase of mental health(depression score) in the intervention group compared to the control group. but without statistical significance. 3) There was a significant improvement in cognitive perception of exercise(e.g. usefulness and self -efficacy) in the intervention group, compared to the control group. It was concluded that the exercise program employed in this study was appropriate for women senior citizens and had a positive effect on health in general.

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봉독이 위암 세포주에 미치는 효과 (Effects of the Bee Venom on Human Gastric Adenocarcinoma Cell Lines)

  • 허경;김명호;임성우
    • 동의생리병리학회지
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    • 제27권1호
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    • pp.92-98
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    • 2013
  • Bee Venom(below BV) has been used in alternative medicine to treat the diseases, such as pain diseases. BV contains a variety of peptides, including melittin, apamin, adolapin, MCD peptide, enzymes(i.e. PLA2), amines(i.e. histamine and epinephrine), and nonpeptide components. The two main components of BV are melittin and PLA2. The cell cytotoxic effects through the activation of PLA2 by melittin have been suggested to be the critical mechanism for the depress of cancer cell. Melittin and PLA2 have been reported to induce apoptosis and to possess anti-cancer effects and neurite outgrowth in PC12 cells. Analysis of proliferation was confirmed by MTT assay. BV decreased cell number through dose- and duration-dependent manner and these effects are apparent at a concentration of 3 ${\mu}g/ml$. To observe which signaling molecules will be activated by BV, phosphorylation of ERK, p38 MAPK, JNK and ERM were examined by Western blot analysis. To study the long term effect of BV in human gastric adenocarcinoma cell lines, the image of cells treated with BV for 4 days were obtained. BV was shown to exhibit anti-cancer activity in human gastric adenocarcinoma cell lines at a broad range of concentrations of 3 ${\mu}g/ml$. ERK, p38 MAPK and JNK were found to increase in BV treated cells. However, ERM which known to be involved in the cell death, was gradually decreased to 30minutes after addition 3 ${\mu}g/ml$ of BV. These results provide a possible BV-induced inhibitory signal for cancer proliferation that is initiated by the decrease in ERM activity. Moreover, it is likely that the activation of ERK, p38 MAPK and JNK are required for the BV-induced inhibition of cancer proliferation.

The Leaching Behavior of Unirradiated $UO_2$ Pellets in Wet Storage and Disposal Conditions

  • Park, Geun-Il;Lee, Hoo-Kun
    • Nuclear Engineering and Technology
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    • 제28권4호
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    • pp.349-358
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    • 1996
  • The leaching behavior of uranium from unirradiated CANDU UO$_2$ fuel pellet in the spent fuel wet storage and disposal conditions has been investigated. A modified IAEA leach test method was used, and then the extent of leaching was monitored by analysis for uranium in the leachant. The leach test has been performed in various leachants(demineralized water and boric acid solution at pH=6, synthetic granite groundwater) for a long-term period of 5.4 years, and the effect of temperature on the leach rate of uranium has been analyzed. The leach rates of uranium at $25^{\circ}C$ were dependent on the leachants. Over initial 100 days of leach periods, the leach rate in groundwater was the highest in three leachants and no significant differences of leach rates ore observed in the demineralized oater and boric acid solution. But these leach rates in three leachants around 2,000 days at $25^{\circ}C$ appeared to be reached the steady rates in the range of 1~5$\times$10$^{-8}$ g/$\textrm{cm}^2$ day. The leach rate of uranium in groundwater shooed to be independent of the temperature, but those in both demineralized water and boric acid solution increased with temperature. These results show that the leaching behavior of uranium from UO$_2$ fuel in both the demineralized water ann boric acid may be controlled tv the surface oxidative.dissolution reaction of UO$_2$ and the leach rate of uranium in groundwater at room temperature could mainly be controlled by the complex reaction of dissolved uranyl ions with carbonate ions and no variation of leach rate of UO$_2$ in groundwater with temperature may be due to the local deposition of passivating uranyl phases on the surface.

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A vision for the Welding Industry in the USA

  • Kim, Dong-Sub
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2000년도 특별강연 및 추계학술발표대회 개요집
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    • pp.13-18
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    • 2000
  • Welding is critical technique for the joining of materials in the nation's major Manufacturing industries. Since 1998, leaders in welding industry have defined a vision of the issues and opportunities that it will face in 2020. In developing this vision document, more than 25 senior managers and respected experts from various segments of the welding community met to begin a dialog about the future of the welding industry. They were brought together to develop a long-range business plan for their industry that would identify how it would meet the needs of manufacturers, of the marketplace, and of society in 2020. In essence, these decision makers created an ideal vision of the state of their industry in 20 years, and the strategy to reach it. Welding is a precise, reliable, and cost-effective, method for joining materials. No other technique is as widely used by manufacturers to join metals and alloys efficiently. Most of the familiar objects in modern society, form buildings and bridges, to vehicles, computers, and medical devices, could not be produced without the use of welding. Despite the importance of welding to the manufacturing industry, the leaders in this area felt that welding was not appreciated as much as it should be from the society. The welding industry consists of the “users” of welding techniques as well as the companies, universities and other organizations that industry look for improvements in their operations by 2020, and should find their interest addressed in this document. A major economic impact study co sponsored by AWS and EWI and supported by US Navy, State of Ohio, US Department of Commerce, and major companies was kicked off. This two-year study will determine the economic impact of welding on the United States economy. The objective of this study is to break a paradigm about welding-those of us who are heavily involved in welding, believe strongly that much of our gross domestic product is directly dependent on welding. Furthermore, continued advances in the field of welding are necessary to achieving further increases in productivity that makes our economy strong. Yet, despite intuition, anecdotal information, and fragmented analyses, the completing quantitative information that would proved the justification for strategic actions to further develop this critical field is not currently available.

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치과의원에 근무하는 일부 치과위생사의 우울수준에 관한 연구 (A study on the degree of depression in dental hygienists)

  • 한세영;이가연
    • 한국치위생학회지
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    • 제9권4호
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    • pp.659-669
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    • 2009
  • Objectives : The degree of depression in dental hygienist was analyzed to reveal the various factors related to them. Methods : The self-administered questionnaires were filled out from 202 dental hygienist in Daejeon City. The survey items included subjects' socio-demographic and job-related characteristics, health-related behaviors, depression. Chi-Square analysis and Pearson's correlation coefficient was put into survey results, in which a degree of depression was dependent variable and others were independent variable. Results : 1. The distribution for depression degree has shown the rate as 80.2% in normal range group and 19.8% in depression group. 2. As for depression, long working hours(p=0.042), poor sense satisfaction in work(p=0.000), not fit to the job(p=0.003), low personal relation with peer works or supervisors(p=0.039), without alcohol drinking(p=0.048), poor subjective condition of health(p=0.000) than their respective counterparts. 3. Concerning correlation between depression and various factors, poor sense satisfaction in work(r=-0.332, p=0.000), not fit to the job(r=-0.353, p=0.000), low personal relation with peer works or supervisors(r=-0.215, p=0.002), without alcohol drinking(r=-0183, p=0.009), poor subjective condition of health(r=-0.333, p=0.000). Conclusions : These results showed that depression state could be influenced by various factors, which include socio-demographic, job-related characteristics and health-related behaviors. Therefore, in order to reduce depression state of dental hygienists, development and application of programs to manage and research for them are required to be revitalized as well as socio-demographic and job-related characteristics and health-related behaviors.

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Selenium in Pig Nutrition and Reproduction: Boars and Semen Quality - A Review

  • Surai, Peter F.;Fisinin, Vladimir I.
    • Asian-Australasian Journal of Animal Sciences
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    • 제28권5호
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    • pp.730-746
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    • 2015
  • Selenium plays an important role in boar nutrition via participating in selenoprotein synthesis. It seems likely that selenoproteins are central for antioxidant system regulation in the body. Se-dependent enzyme glutathione peroxidase (GSH-Px) is the most studied selenoprotein in swine production. However, roles of other selenoproteins in boar semen production and maintenance of semen quality also need to be studied. Boar semen is characterised by a high proportion of easily oxidized long chain polyunsaturated fatty acids and requires an effective antioxidant defense. The requirement of swine for selenium varies depending on many environmental and other conditions and, in general, is considered to be 0.15 to 0.30 mg/kg feed. It seems likely that reproducing sows and boars are especially sensitive to Se deficiency, and meeting their requirements is an important challenge for pig nutritionists. In fact, in many countries there are legal limits as to how much Se may be included into the diet and this restricts flexibility in terms of addressing the Se needs of the developing and reproducing swine. The analysis of data of various boar trials with different Se sources indicates that in some cases when background Se levels were low, there were advantages of Se dietary supplementation. It is necessary to take into account that only an optimal Se status of animals is associated with the best antioxidant protection and could have positive effects on boar semen production and its quality. However, in many cases, background Se levels were not determined and therefore, it is difficult to judge if the basic diets were deficient in Se. It can also be suggested that, because of higher efficacy of assimilation from the diet, and possibilities of building Se reserves in the body, organic selenium in the form of selenomethionine (SeMet) provided by a range of products, including Se-Yeast and SeMet preparations is an important source of Se to better meet the needs of modern pig genotypes in commercial conditions of intensive pig production.

2-Methacryloxyethyl dimethyl 2-hydroxyethyl ammonium bromide를 이용한 고분자 습도센서의 감습 특성 및 신뢰성 (Humidity-Sensitive Characteristics and Reliabilities of Polymeric Humidity Sensors Using 2-Methacryloxyethyl dimethyl 2-hydroxyethyl ammonium brornide)

  • 이칠원;공명선
    • 공업화학
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    • 제10권3호
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    • pp.461-466
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    • 1999
  • 암모늄염을 포함하는 고분자 습도센서를 2-methacryloxyethyl dimethyl 2-hydroxyethyl ammonium bromide (MDHAB)/MMA/DAEMA=6/3/1의 공중합체로부터 제조하였다. 감습막은 금/알루미나 전극에 침적법에 의하여 도포하였으며 $5^{\circ}C$, 40%RH, 70%RH, 그리고 90%RH에서 전형적인 임피던스는 각각 $298k{\Omega},\;11k{\Omega}$, 그리고 $2.3k{\Omega}$을 나타내어 감습특성은 저온에서 사용되는 습도 센서로서의 특성에 적합하였다. 온도 의존성 계수는 $5{\sim}20^{\circ}C$에서 $-0.80%RH/^{\circ}C$이었으며 히스테리시스는 ${\pm}2%RH$ 이내에 존재하였다. 응답 속도는 34%RH에서 88%RH로 변화할 때 38초였다. 신뢰성 시험으로서 온도 사이클, 습도 사이클, 고온 고습 저항성, 전기 인가, 장기 방치, 그리고 내수성을 측정하여 습도센서로서의 응용성을 평가하였다.

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포스포늄 염을 가진 고분자 습도센서의 감습 특성 및 신뢰성 (Humidity-Sensitive Characteristics and Reliabilities of Polymeric Humidity Sensor Containing Phosphonium Salts)

  • 김오영;공명선
    • 공업화학
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    • 제9권4호
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    • pp.554-560
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    • 1998
  • 포스포늄 염을 포함하는 감습성 전해질 고분자 결로센서를 vinylbenzyl triphenyl phosphonium chloride(VTPC)/styrene=3/7의 공중합체로부터 제조하였다. 감습막은 금/알루미나 전극에 침적법에 의하여 도포하였으며 $25^{\circ}C$의 70%RH, 80%RH, 90%RH, 그리고 95% RH에서 임피던스는 $11M{\Omega}$, $980k{\Omega}$, $50k{\Omega}$, 그리고 $11k{\Omega}$를 각각 보여 주어 감습 특성은 결로 센서로서의 특성에 매우 적합하였으며 $15{\sim}35^{\circ}C$에서 온도 의존성 계수는 $-0.25%RH/^{\circ}C$이었으며 히스테리시스는 ${\pm}2%RH$ 이내에 존재하였다. 응답 속도는 70%RH에서 98%RH로 변화할 때 45초이었다. 신뢰성 시험으로서 온도 사이클, 습도 사이클, 고온 고습 저항성, 전기 인가, 장기 방치, 그리고 내수성을 측정하여 결로 센서로서의 적합성을 평가하였다.

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