• 제목/요약/키워드: tolerance analysis

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Effects of Ischemic Preconditioning of Different Intraoperative Ischemic Times of Vascularized Bone Graft Rabbit Models

  • Halim, Ahmad Sukari;Wan Ahmad Kamal, Wan Syazli Rodzaian;Noor, Norizal Mohd;Abdullah, Shafie
    • Archives of Plastic Surgery
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    • 제40권6호
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    • pp.687-696
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    • 2013
  • Background Ischemic preconditioning has been shown to improve the outcomes of hypoxic tolerance of the heart, brain, lung, liver, jejunum, skin, and muscle tissues. However, to date, no report of ischemic preconditioning on vascularized bone grafts has been published. Methods Sixteen rabbits were divided into four groups with ischemic times of 2, 6, 14, and 18 hours. Half of the rabbits in each group underwent ischemic preconditioning. The osteomyocutaneous flaps consisted of the tibia bone, from which the overlying muscle and skin were raised. The technique of ischemic preconditioning involved applying a vascular clamp to the pedicle for 3 cycles of 10 minutes each. The rabbits then underwent serial plain radiography and computed tomography imaging on the first, second, fourth, and sixth postoperative weeks. Following this, all of the rabbits were sacrificed and histological examinations were performed. Results The results showed that for clinical analysis of the skin flaps and bone grafts, the preconditioned groups showed better survivability. In the plain radiographs, except for two non-preconditioned rabbits with intraoperative ischemic times of 6 hours, all began to show early callus formation at the fourth week. The computed tomography findings showed more callus formation in the preconditioned groups for all of the ischemic times except for the 18- hour group. The histological findings correlated with the radiological findings. There was no statistical significance in the difference between the two groups. Conclusions In conclusion, ischemic preconditioning improved the survivability of skin flaps and increased callus formation during the healing process of vascularized bone grafts.

연속철근콘크리트 포장의 횡방향 철근 설계방법 및 시공관련 이슈 검토 (Construction Issues and Design Procedure for Transverse Steel in Continuously Reinforced Concrete Pavement (CRCP))

  • 최판길;원문철
    • 한국도로학회논문집
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    • 제16권4호
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    • pp.1-9
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    • 2014
  • PURPOSES: The objective of this study is to evaluate construction issues and design for transverse steel in continuously reinforced concrete pavement(CRCP). METHODS : The first continuously reinforced concrete pavement(CRCP) design procedure appeared in the 1972 edition of the "AASHTO Interim Guide for Design of Pavement Structures", which was published in 1981 with Chapter 3 "Guide for the Design of Rigid Pavement" revised. A theory that was accepted at that time for the analysis of steel stress in concrete pavement, called subgrade drag theory(SGDT), was utilized for the design of reinforcement of CRCP - tie bar design and transverse steel design - in the aforementioned AASHTO Interim Guide. However SGDT has severe limitations due to simple assumptions made in the development of the theory. As a result, any design procedures for reinforcement utilizing SGDT may have intrinsic flaws and limitations. In this paper, CRCP design procedure for transverse steel was introduced and the limitations of assumptions for SGDT were evaluated based on various field testing. RESULTS: Various field tests were conducted to evaluate whether the assumptions of SGDT are reasonable or not. Test results show that 1) temperature variations exist along the concrete slab depth, 2) very little stress in transverse steel, and 3) warping and curling in concrete slab from the field test results. As a result, it is clearly revealed out that the assumptions of SGDT are not valid, and transverse steel and tie bar designs should be based on more reasonable theories. CONCLUSIONS : Since longitudinal joint is provided at 4.1-m spacing in Korea, as long as joint saw-cut is made in accordance with specification requirements, the probability of full-depth longitudinal cracking is extremely small. Hence, for transverse steel, the design should be based on the premise that its function is to keep the longitudinal steel at the correct locations. If longitudinal steel can be placed at the correct locations within tolerance limits, transverse steel is no longer needed.

개 생균제 사용에 적합한 유산균주의 선발 및 면역활성 평가 (Selection and immunomodulatory evaluation of lactic acid bacteria suitable for use as canine probiotics)

  • 박수민;박호은;이완규
    • 대한수의학회지
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    • 제55권2호
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    • pp.81-88
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    • 2015
  • This study was conducted to isolate lactic acid bacteria (LAB) from dog intestine and identify potential probiotic strains for canine use. One hundred and one LAB were isolated from feces of 20 healthy dogs. Acid, bile, and heat resistance along with adherence to Caco-2 cells and antimicrobial activity against pathogens were examined. To analyze immunomodulative effects, the production of nitric oxide (NO), TNF-${\alpha}$, and IL-$1{\beta}$ was measured using RAW 264.7 macrophages. Additionally, RAW BLUE cells were used to evaluate nuclear factor-${\kappa}B$ (NF-${\kappa}B$) generation. Ultimately, three strains were selected as canine probiotics and identified as Lactobacillus reuteri L10, Enterococcus faecium S33, and Bifidobacterium longum B3 by 16S rRNA sequence analysis. The L10 and S33 strains showed tolerance to pH 2.5 for 2 h, 1.0% Oxgall for 2 h, and $60^{\circ}C$ for 5 min. These strains also had strong antimicrobial activity against Escherichia coli KCTC 1682, Salmonella Enteritidis KCCM 12021, Staphylococcus aureus KCTC 1621, and Listeria monocytogenes KCTC 3569. All three strains exerted better immunomodulatory effects than Lactobacillus rhamnosus GG (LGG), a well-known commercial immunomodulatory strain, based on NO, NF-${\kappa}B$, IL-$1{\beta}$, and TNF-${\alpha}$ production. These results suggested that the three selected strains could serve as canine probiotics.

Microbiological Contamination and Sanitary Management of Aquarium Water in the Busan Area

  • Cho, Kyung-Soon
    • 대한임상검사과학회지
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    • 제46권1호
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    • pp.1-11
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    • 2014
  • This research has been performed by our own investigation, also cooperated with Health and Sanification Division and each of district offices in Busan metropolitan city. After choosing, we collected water samples five times for microbiological examination. As a result of investigating in 160 water samples from urban areas, we could detect 88 cases of Vibrio spp. Furthermore, there were four cases exceeding the acceptable limit of aquarium water (100,00/mL) and another four cases exceeding the limit of Coliform group (1,000 below/100 mL). As a result of investigating that we performed for 271 cases of water samples from coastal areas from April to November, we could detect 130 cases of vibrio species and 10 cases of Coliform group. After performing 17 kinds of antibiotic susceptibility test for 41 cases of isolated Vibrio parahaemolyticus, 27 cases showed tolerance to Amplicllin (AM), all of 31 cases showed intermediate resistance only to Cefazolin (CF) but had sensitivity to the rest of them. As a result of performing antibiotic susceptibility test, serum test and PFGE gene analysis on each 10 pair of Vibrio parahaemolyticus detected concurrently from intake-pipe water and, aquarium water, we couldn't get data showing that they are clearly same species in three kinds of test. In addition, UV sterilization, Ozonization and so on. Based on our research, intake pipe didn't have a problem with microbiological contamination so we are sure that the germ came from supplied fish had caused that kind of contamination. For effective management, UV sterilization or Ozonization which can be handled consistently should be adopted in aquarium.

Screening and Characterization of Lactic Acid Bacteria Strains with Anti-inflammatory Activities through in vitro and Caenorhabditis elegans Model Testing

  • Lee, Hye Kyoung;Choi, Sun-Hae;Lee, Cho Rong;Lee, Sun Hee;Park, Mi Ri;Kim, Younghoon;Lee, Myung-Ki;Kim, Geun-Bae
    • 한국축산식품학회지
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    • 제35권1호
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    • pp.91-100
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    • 2015
  • The present study was conducted to screen candidate probiotic strains for anti-inflammatory activity. Initially, a nitric oxide (NO) assay was used to test selected candidate probiotic strains for anti-inflammatory activity in cultures of the murine macrophage cell line, RAW 264.7. Then, the in vitro probiotic properties of the strains, including bile tolerance, acid resistance, and growth in skim milk media, were investigated. We also performed an in vitro hydrophobicity test and an intestinal adhesion assay using Caenorhabditis elegans as a surrogate in vivo model. From our screening, we obtained 4 probiotic candidate lactic acid bacteria (LAB) strains based on their anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 cell cultures and the results of the in vitro and in vivo probiotic property assessments. Molecular characterization using 16S rDNA sequencing analysis identified the 4 LAB strains as Lactobacillus plantarum. The selected L. plantarum strains (CAU1054, CAU1055, CAU1064, and CAU1106) were found to possess desirable in vitro and in vivo probiotic properties, and these strains are good candidates for further investigations in animal models and human clinical studies to elucidate the mechanisms underlying their anti-inflammatory activities.

Reference Equations for the Six-Minute Walk Distance in Healthy Korean Adults, Aged 22-59 Years

  • Kim, Ah Lim;Kwon, Jae Choon;Park, In;Kim, Ji Na;Kim, Jong Min;Jeong, Bi Na;Yu, Sung Ken;Lee, Byung Ki;Kim, Yeon Jae
    • Tuberculosis and Respiratory Diseases
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    • 제76권6호
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    • pp.269-275
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    • 2014
  • Background: The six-minute walk test has been widely used in people with chronic cardiopulmonary disorders as an outcome assessment with regards to therapeutic or prognostic determinants. This study was undertaken to determine the six-minute walk distance (6MWD) in a sample of healthy Koreans and to create a reference equation. We also compared the 6MWD of our cohort with previously published equations. Methods: Two hundred fifty-nine healthy subjects (95 males) aged 22-59 years performed two walking tests using a standardized protocol. 6MWD was defined as the greatest distance achieved from the two tests. The effect of anthropometrics on the 6MWD was also investigated. Results: The average 6MWD was $598.5{\pm}57.92m$, with significantly longer distances by males ($628.9{\pm}59.51m$) than females ($580.9{\pm}47.80m$) (p<0.001). Age, height, weight, and body mass index were significantly correlated with 6MWD in univariate analysis. Stepwise multiple regression showed height to be single independent predictor of 6MWD ($r^2$=0.205, p<0.001). The reference equations derived in Caucasian and North African populations tend to overestimate the distance walked by Korean subjects, while Asian equations underestimate it. Conclusion: The average 6MWD in these Korean populations was 600 m. The regression equation revealed that individual's height was the most significant predictor of distance, explaining 20.5% of the distance variance.

공정능력지수 Ĉp, Ĉpk와 Ĉpm를 위한 점근적 상관성에 관한 연구 (On the asymptotic correlationship for some process capability indices Ĉp, Ĉpk and Ĉpm)

  • 조중재;유혜경
    • Journal of the Korean Data and Information Science Society
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    • 제24권3호
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    • pp.465-475
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    • 2013
  • 공정능력을 측정하고 분석하기 위하여 공정능력지수가 매우 중요한 역할을 한다. 흔히 품질수준은 공정능력지수들에 의해 측정된다. 세 가지 공정능력지수 $C_p$, $C_{pk}$, $C_{pm}$들은 품질 현장에서 프로세스 성과를 평가하는 데 널리 유용하게 사용되는 바, 이들 추정량들의 상관관계를 보다 명확하게 규명, 연구하여 적절히 활용할 필요가 있다. 본 논문에서는 공정표본이 정규분포에 따를 때 이러한 지수들의 추정량들에 대한 점근적 상관성을 연구하였다. 제2절에서는 공정능력지수 $C_p$, $C_{pk}$, $C_{pm}$들을 정의하여 기본적인 관계를 설명하였고, 제3절에서는 단일변량 정규공정하에서의 점근적인 상관계수를 구체적으로 계산, 규명하였다. 이러한 연구결과를 이용하여 보다 정확한 공정능력지수들의 상관관계를 통해 필요한 분석을 수행하는 것이 바람직할 것이다.

다중경로 라우팅 기반 Ad-hoc Networks에서 IEEE 802.11 RTS/CTS 핸드세이크 오버헤드 분석 (Analysis the Overhead of IEEE 802.11 RTS/CTS Handshake in Ad-hoc Networks Based Multipath Routing)

  • 김현창;이재용
    • 전자공학회논문지CI
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    • 제45권6호
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    • pp.33-44
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    • 2008
  • 이동노드들의 예측 불가능한 이동, 적은 대역폭의 무선링크 사용으로 인하여 데이터 전송 실패율이 높은 Ad-hoc Networks에서 다중경로 라우팅은 단일경로 라우팅에 비해 트래픽 분산, 내고장성 높은 군집 대역폭을 제공하여 데이터 전송의 신뢰성 경로의 견고성을 유지할 수 있다. 그러나 다중경로 라우팅은 경로를 설정하고 유지하는 과정에서 오버헤드가 추가적으로 발생하여 Ad-hoc Networks에서 무선자원의 효율적인 사용을 제한한다. 본 논문에서는 다중경로 라우팅 기반 Ad-hoc Networks에서 IEEE 802.11 DCF의 RTS/CTS 핸드세이크로 인해 발생하는 오버헤드의 영향을 분석하고자 한다. 이를 위하여 Ad-hoc Networks에서 RTS/CTS 핸드세이크의 운용 및 문제점을 설명하였고, 요구기반 단일경로 라우팅에서 RTS/CTS 핸드세이크의 오버헤드 영향을 분석했다. 또한, 수학적인 분석을 위하여 요구기반 단일경로 다중경로 라우팅의 네트워크 모델을 제시하였다. 다양한 실험을 통하여 다중경로 라우팅에서 최적의 경로 수와 경로 길이를 찾아내어, 향후 다중경로 라우팅 연구를 위한 기반을 제시하였다.

청소년의 인터넷 중독현상과 자기통제기대의 구조적 경로모형에 관한 연구 (The Structural Path Model of Adolescents′ Internet Addiction and Expected Self-Control)

  • 박재성
    • 보건교육건강증진학회지
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    • 제21권3호
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    • pp.1-17
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    • 2004
  • The purpose of this study is to evaluate the roles of expected self-control and expected self-control results in explaining adolescents' Internet addiction. In the study model, expectations of self-control and self-control results directly determine Internet addiction and Internet use time meditates the impacts of expectations of self-control and self-control results on Internet addiction. The study subjects are 1,080 middle and high school students in Busan. Stratified cluster sampling is applied by school type and school year. The response rate is 96%(l,037cases). This study develops the scales of expected self-control and expected self-control results. The scales of Internet addiction are devised by using the concept of functional dependency such as salience, withdrawal symptoms, mood modification, tolerance, relapse, and conflict. For verifying the study model, path analysis and multiple regression models are applied for identifying path significants and evaluating confounding effects of control variables, respectively. Moreover, multi partial F-test is performed for selecting the best regression model. Expected self-control is a significant determinant of Internet addiction and Internet use time that also significantly explains Internet addiction. The total effect of expected self-control towards Internet addiction is -.95. The total effect is comprised with the direct effect (-.71) and the indirect effect(-.24). In this result, the direct effect refers a curative effect since expected self-control directly reduces the level of Internet addiction, and the indirect effect refers a preventive effect because self-control can reduce time of Internet use that is a direct determinant of Internet addiction. In the test of the confounding effects of control variables, there are no confounding effects in the models of multiple regression. It implies a robustness of the study model as regards control variables. In conclusion, improving adolescents' expected self-control can control Internet addiction level. This finding implies that a health promotion program for improving expected self-control can be a cost effective method compared to other approaches.

Calcium Signaling-mediated and Differential Induction of Calmodulin Gene Expression by Stress in Oryza sativa L.

  • Phean-o-pas, Srivilai;Punteeranurak, Pornpimon;Buaboocha, Teerapong
    • BMB Reports
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    • 제38권4호
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    • pp.432-439
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    • 2005
  • $Ca^{2+}$/calmodulin transduction pathways have been implicated in mediating stress response and tolerance in plants. Here, three genes encoding calmodulin (Cam) members of the EF-hand family of $Ca^{2+}$-binding proteins were identified from Oryza sativa L. databases. Complementary DNA for each of the calmodulin genes, OsCam1, OsCam2, and OsCam3 were sequenced. OsCam1 and OsCam2 encode a conventional 148-amino acid calmodulin protein that contains four characteristic $Ca^{2+}$-binding motifs. OsCam3 encode a similar protein with a 38-amino-acid extension containing a putative prenylation site (CVIL) at the carboxyl terminus. RT-PCR showed that each of the genes is expressed in leaves and roots of 2-week old rice seedlings. By RNA gel blot analysis, OsCam1 mRNA levels strongly increased in response to NaCl, mannitol and wounding treatments. In contrast, OsCam2 mRNA levels were relatively unchanged under all conditions investigated. NaCl treatment and wounding also increased the OsCam3 mRNA level, but in a more transient manner. Our results indicate that although the expression of genes encoding different calmodulin isoforms is ubiquitous, they are differentially regulated by various stress signals. In addition, we have demonstrated that the calcium-channel blocker lanthanum chloride inhibited the induction of OsCam1 gene expression by both NaCl and mannitol treatments. These results suggest that osmotic stress induced expression of OsCam1 gene requires the $[Ca^{2+}]_{cyt}$ elevation that is known to occur in response to these stimuli.