• Title/Summary/Keyword: Negative-U center

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An Efficient Secretion of Type I Secretion Pathway-Dependent Lipase, TliA, in Escherichia coli: Effect of Relative Expression Levels and Timing of Passenger Protein and ABC Transporter

  • Eom Gyeong-Tae;Rhee Joon-Shick;Song Jae-Kwang
    • Journal of Microbiology and Biotechnology
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    • v.16 no.9
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    • pp.1422-1428
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    • 2006
  • An ABC transporter apparatus of the Gram-negative bacterial type I secretion pathway can be used as a secretory protein expression system in Escherichia coli. Four types of coexpression systems for the Pseudomonas fluorescens lipase gene, tliA, and its cognate ABC transporter gene cluster, tliDEF, were constructed. When the relative expression levels were changed by adding different concentrations of IPTG, the secretion (16.9 U/ml of culture) of TliA in E. coli [pTliDEFA-223+pACYC184] was significantly higher than E. coli [pKK223-3+pTliDEFA-184] secreting the lowest level of TliA (5.2 U/ml of culture). Maximal accumulation of the lipase secreted occurred in the mid-exponential phase, implying that the efficient protein secretion via an ABC transporter was restricted only to actively growing cells. Finally, the secretion level of TliA in E. coli [pTliDEFA-223+pACYC184] was increased to 26.4 U/ml by inducing gene expression at the culture initiation time. These results indicate that a significant increase in the ABC transporter-dependent protein secretion can be achieved by simply controlling the relative expression levels between the ABC transporter and its passenger protein, even in the recombinant E. coli cells.

Hand Surgery Fellowship Selection Criteria: A National Fellowship Director Survey

  • Egro, Francesco M.;Vangala, Sai K.;Nguyen, Vu T.;Spiess, Alexander M.
    • Archives of Plastic Surgery
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    • v.44 no.5
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    • pp.428-433
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    • 2017
  • Background Candidate characteristics for hand surgery fellowship training remains unknown, as very little data is available in the literature. This study aims to provide information on the criteria that are employed to select candidates for the hand surgery fellowship match. Methods A 38-question survey was sent in April 2015 to all Accreditation Council for Graduate Medical Education recognized hand surgery fellowship program directors (n=81) involved in the U.S. match. The survey investigated factors used for the selection of applicants, including medical school, residency training, research experience, fellowship interview, and candidate characteristics. A 5-point Likert scale was used to grade 33 factors from "not at all important" (1) to "essential in making my decision" (5); or for five controversial factors from "very negative impact" (1) to "very positive impact in making my decision" (5). Results A total of 52% (42 out of 81) of responses were received from hand surgery fellowship program directors. The most important influential factors were interactions with faculty during interview and visit ($4.6{\pm}0.6$), interpersonal skills ($4.6{\pm}0.5$), overall interview performance in the selection process ($4.6{\pm}0.6$), professionalism and ethics ($4.6{\pm}0.7$), and letters of recommendation from hand surgeons ($4.5{\pm}0.7$). Factors that have a negative impact on the selection process include visa requirement ($2.1{\pm}1.2$), graduate of non-plastic surgery residency program ($2.4{\pm}1.3$), and graduate of a foreign medical school ($2.4{\pm}1.1$). Conclusions This study provides data on hand surgery fellowship directors' perception on the criteria important for fellowship applicant selection, and showed that interview-related criteria and letters of recommendation are the important factors.

A Numerical Study on the Flow Development around a Rotating Square-Sectioned U-Bend (I) - Laminar Flow - (회전하는 정사각 단면 U자형 곡관 내부의 유동 발달에 관한 수치적 연구 (I) - 층류 유동)

  • Lee, Gong-Hui;Baek, Je-Hyeon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.1
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    • pp.159-169
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    • 2002
  • The present study investigates in detail the combined effects of the Coriolis and centrifugal farce on the development of laminar flows in a square-sectioned U-bend rotating about an axis parallel to the center of bend curvature. When a viscous fluid flows through a rotating curved region, two types of secondary flow occur. One is caused by the Coriolis force due to the rotation of U-bend and the other by the centrifugal farce due to the curvature of U-bend. When the values of Rossby number and curvature ratio are large, the flow field in a rotating U-bend can be represented by two dimensionless parameters ; the Dean number K$\_$LC/=Re/√λ and a body ratio F=λ/Po. For positive rotation, where the rotation is in the same direction as that of the main flow, both the Coriolis force and the centrifugal force act radially outwards, the directions of the two secondary flows are the same. Therefore, the flow structure is qualitatively similar to that observed in a stationary curved duct with a larger f7c. On the other hand, in case of negative rotation, where two farces act in opposite direction, more complex flow fields can be observed depending on the relative magnitudes of the forces.

Detection of Illegal U-turn Vehicles by Optical Flow Analysis (옵티컬 플로우 분석을 통한 불법 유턴 차량 검지)

  • Song, Chang-Ho;Lee, Jaesung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.10
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    • pp.948-956
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    • 2014
  • Today, Intelligent Vehicle Detection System seeks to reduce the negative factors, such as accidents over to get the traffic information of existing system. This paper proposes detection algorithm for the illegal U-turn vehicles which can cause critical accident among violations of road traffic laws. We predicted that if calculated optical flow vectors were shown on the illegal U-turn path, they would be cause of the illegal U-turn vehicles. To reduce the high computational complexity, we use the algorithm of pyramid Lucas-Kanade. This algorithm only track the key-points likely corners. Because of the high computational complexity, we detect center lane first through the color information and progressive probabilistic hough transform and apply to the around of center lane. And then we select vectors on illegal U-turn path and calculate reliability to check whether vectors is cause of the illegal U-turn vehicles or not. Finally, In order to evaluate the algorithm, we calculate process time of the type of algorithm and prove that proposed algorithm is efficiently.

How much change is optimal when a brand is newly rebranded?

  • Chu, Kyounghee;Lee, Doo-Hee;Yeu, Minsun;Park, Sangtae
    • Asia Marketing Journal
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    • v.15 no.4
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    • pp.161-186
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    • 2014
  • There are many cases of rebranding and its numbers are growing. However, rebranding is still under research in the academic field, and there is no guideline on the effective way to change brand name. The objective of this paper is to integrate two inconsistent predictions from categorization theory and schema incongruity theory: a negative linear relationship (categorization theory) versus an inverted-U-shape relationship (schema incongruity theory) between brand name incongruity and consumer evaluation into one framework. Specifically, this study examines how the effect of incongruity between an existing brand name and a new brand name (hereafter called "brand name incongruity") on the new brand name attitude differs depending on a consumer's individual characteristics (need for cognition). The experiment demonstrates that consumers with a high need for cognition show a better attitude towards a new brand name when the brand name was rebranded moderately incongruent compared to congruent or extremely incongruent. Thus, the experiment demonstrates that there is an inversed U-shape relationship between brand name incongruity and new brand name evaluation for consumers with a high need for cognition. On the contrary, consumers with a low need for cognition show a better attitude towards a new brand name when the brand name is rebranded congruently compared to incongruent conditions (moderate incongruity and extreme incongruity). This result indicates that there is a negative linear relationship between brand name incongruity and new brand name evaluation. Key theoretical and managerial implications of the present study are as follows. This study integrates two alternative views of research on incongruity evaluation into one framework by demonstrating that need for cognition moderates the relationship between brand name incongruity and consumer evaluation. This present study provides a conceptual basis for understanding consumer evaluation towards a new brand name. Next, though rebranding is a very important decision making of brand management, there is no guideline on how to change a brand name. The findings of this research can suggest which degree of change is optimal when rebranding in order to utilize and strengthen existing brand equity. More specifically, when our target customer has high need for cognition, moderately incongruent rebranding can be optimal, whereas for those with low need for cognition, rebranding in accordance with existing brand name will be optimal.

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Anatomical factors of the maxillary tuberosity that influence molar distalization

  • Diego Fernando Lopez;David Acosta Olmos;Monica Andrea Morales
    • The korean journal of orthodontics
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    • v.54 no.4
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    • pp.239-246
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    • 2024
  • Objective: To examine the areas of the maxillary tuberosity (MT) (coronal, apical, width, and height) with respect to the presence or absence of the third molar to establish possible anatomical limitations for molar distalization. Methods: A total of 277 tuberosities were evaluated through sagittal computed tomography (CT) images, divided for measurement into coronal (free of bone), apical (area of influence of the maxillary sinus), and tuberosity (bony area) zones, and stratified by the presence or absence of the third molar, sex, and two age subgroups. Mann-Whitney U test was used to compare the groups considering the third molar. Results: The medians of the width and height of the tuberosity decreased significantly in the absence of the third molar (P < 0.001). The apical area also showed differences, with negative values in the absence of the third molar and positive values in the presence of the third molar (P < 0.001). However, no differences were observed for the coronal area (P > 0.05). Conclusions: In the absence of the third molar, the size of the MT, represented by its width and height, was smaller and negative values (decrease) were observed for the maxillary sinus. The sagittal CT provides useful information regarding the amount of bone tissue available for distalization and relationship of the second molar with respect to the maxillary sinus, which allows individualizing each case in relation to the amount and type of movement expected.

A Study on Indoor Radon Concentrations in Urban Area (도시 일부지역에서의 실내 라돈농도에 관한 연구)

  • 김순애;백남원
    • Journal of Environmental Health Sciences
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    • v.28 no.2
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    • pp.89-98
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    • 2002
  • This study was taken in general hospital, hotel, shopping center, underground cafe, school, house, for the purpose of investigating the distribution of indoor radon concentration in urban area, by E-PERM which approved U.S. EPA, between August and November 1999. There are two sampling Places were exceed 148 ㏃/㎥(4 pCi/L; U.S EPA remedial level), difference mean is 24.0㏃/㎥ when compared with underground vs. aboveground indoor radon concentration in the same building and ratio is 1.6, so underground area is higher than aboveground (p<0.05). Influencing factors were examined. They related to the location of sampler(detector) open or near the door is lower radon concentration than inside portion, which explains probably open area has better ventilated air and dilutes indoor radon concentration. Temperature has a negative relationship (p<0.05) with indoor radon concentration and relative humidity has a positive (p<0.05) Simultaneously to investigate water radon concentration, collected piped-water and the results were very low, which is the same in piped-water concentration other countries. In conclusion, underground indoor radon concentration is higher than aboveground. Concentration was related to sampling spot, open portion is lower than inside. Higher the temperature, lower the indoor radon concentrations. On the other hand higher the relative humidity, higher the indoor radon concentrations. Indoor radon concentration is influenced by sampling point, temperature, relative humidity.

A Monte Carlo Computer Simulation Study for Blue Crab Capture Efficiency Experiment

  • ENDO Shinichi;ZHANG Chang Ik
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.6
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    • pp.720-727
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    • 1995
  • A Monte Carlo computer simulation study was conducted to determine the most efficient sampling design for the blue crab dredge capture efficiency experiment performed in Chesapeake Bay, Maryland, U. S. A. The input values were the number of dredge tracks in each experimental area, the number of tows per experiment, the number of experiments, the mean density of crabs per unit area, the negative binomial coefficient, the gear capture efficiency, and the tow error. As a result of the study, a four-track experiment with twenty to twenty-eight tows was estimated to be the best in terms of precision and accuracy of the gear capture efficiency.

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Early Postmortem Processing Conditions on Meat Quality of Hanwoo (Korean Native Cattle) Beef during Storage

  • Kim, B.C.;Rhee, M.S.;Ryu, Y.C.;Imm, J.Y.;Koh, K.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.12
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    • pp.1763-1768
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    • 2001
  • The combined effects of low voltage electrical stimulation (ES) and early short-term temperature conditioning on meat quality of Hanwoo beef (Korean native cattle) during storage were investigated. Shear force was influenced by ES and aging. Combination of ES and the $30^{\circ}C$ conditioning resulted in higher myofibril fragmentation index and improved lightness. There was no substantial difference in drip loss among treatments but ES samples showed higher cooking loss than control. Negative effect on shelf-life was not found by early short-term high temperature conditioning. Therefore, the meat quality of Korean native cattle was effectively improved by the combination of ES and the $30^{\circ}C$ conditioning.

Inverse behavior of IL-23R and IL-17RA in chronic and aggressive periodontitis

  • Ruiz-Gutierrez, Alondra del Carmen;Rodriguez-Montano, Ruth;Pita-Lopez, Maria Luisa;Zamora-Perez, Ana Lourdes;Guerrero-Velazquez, Celia
    • Journal of Periodontal and Implant Science
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    • v.51 no.4
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    • pp.254-263
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    • 2021
  • Purpose: Periodontitis is associated with a dysbiosis of periodontopathic bacteria, which stimulate the interleukin (IL)-23/IL-17 axis that plays an essential role in the immunopathogenesis of this disease, leading to alveolar bone destruction through receptor activator of nuclear factor κB ligand (RANKL). IL-23 receptor mRNA (IL-23R) has been identified in periodontitis, and IL-17 receptor A mRNA (IL-17RA) and its protein have not yet been evaluated in patients with periodontitis. In this study was measure IL-23R and IL-17RA in gingival tissue (GT) from patients with generalized chronic periodontitis (GCP) and generalized aggressive periodontitis (GAP) and to explore correlations with clinical parameters. Methods: We included 16 healthy subjects (HS), 18 patients with GCP, and 14 with GAP. GT samples were collected during periodontal surgery. Both IL-23R and IL-17RA were detected by enzyme-linked immunosorbent assay. Results: The results were analyzed with Mann-Whitney U test and Spearman' rank correlation coefficients using SPSS version 25.0. We found lower IL-23R levels in patients with GCP and GAP than in HS. Contrarily, we observed higher IL-17RA levels in GCP and GAP patients than in HS. Moreover, we found negative correlations between IL-23R in GT and probing depth and clinical attachment loss (CAL). Likewise, a positive correlation of IL-17RA in GT with CAL was found. Conclusions: The results of these findings suggest that the reverse behavior between IL-23R and IL-17RA in periodontitis patients may also be involved with the activation of RANKL, which promotes alveolar bone loss.