• Title/Summary/Keyword: 저항변화

Search Result 3,805, Processing Time 0.032 seconds

Histological Periodontal Tissue Reaction to Rapid Tooth Movement by periodontal Distraction in Dogs (치주인대 신장에 의한 치아의 급속 견인 시 성견 치주조직의 변화)

  • Chang, Young-Il;Kim, Tae-Woo;Choi, Hee-Young
    • The korean journal of orthodontics
    • /
    • v.32 no.6 s.95
    • /
    • pp.455-466
    • /
    • 2002
  • The objective of this study was to evaluate the changes that occurred over time in the distracted periodontal ligament space following the rapid retraction of a tooth by periodontal distraction after bone undermining surgery had been conducted in the dogs. The upper second premolars were extracted on the left and right side in 4 male beagle dogs. Immediately after extraction, the interseptal bone distal to the upper first premolar was thinned and undermined by grooving to decrease the bone resistance. Activating an individualized distraction appliance at the rate of 0.225mm twice a day, the upper first premolar was retracted rapidly toward the extraction socket. Periodontal distractions were performed for 5, 10, and 20 days, and 20-day-distraction cases were followed by maintenance periods of 0, 14, 28, and 56 days. After 20 days of rapid retraction, the average distal movement of the upper first premolar was 5.02mm, and the average mesial movement of the upper third premolars serving as an anchorage unit was 0.18 mm. On histological examination, the regeneration of bone occurred in a highly organized pattern. Distracted periodontal ligament space was filled with newly formed bone oriented in the direction of the distraction, and this was followed by extensive bone remodeling. This result was similar to those observed in other bones after distraction osteogenesis. In the periodontal ligament, the relationship between collagen fibers and cementum began to be restored 2 weeks after the distraction was completed, and showed almost normal features 8weeks after the completion of the periodontal distraction. However, on the alveolar side, the new bone formation was still in process and collagen fiber bundles and Sharpey's fibers were not present 8 weeks after the completion of the periodontal distraction. Reactions in the periodontal ligament of the anchorage tooth represented bone resorption on the compressed side and new bone deposition on the tension side as occurred in conventional orthodontic tooth movement. In conclusion, the results of this study showed that periodontal structures on the distracted side of the periodontal ligament were regenerated well histologically following rapid tooth movement.

Radiation, Energy, and Entropy Exchange in an Irrigated-Maize Agroecosystem in Nebraska, USA (미국 네브라스카의 관개된 옥수수 농업생태계의 복사, 에너지 및 엔트로피의 교환)

  • Yang, Hyunyoung;Indriwati, Yohana Maria;Suyker, Andrew E.;Lee, Jihye;Lee, Kyung-do;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.22 no.1
    • /
    • pp.26-46
    • /
    • 2020
  • An irrigated-maize agroecosystem is viewed as an open thermodynamic system upon which solar radiation impresses a large gradient that moves the system away from equilibrium. Following the imperative of the second law of thermodynamics, such agroecosystem resists and reduces the externally applied gradient by using all means of this nature-human coupled system acting together as a nonequilibrium dissipative process. The ultimate purpose of our study is to test this hypothesis by examining the energetics of agroecosystem growth and development. As a first step toward this test, we employed the eddy covariance flux data from 2003 to 2014 at the AmeriFlux NE1 irrigated-maize site at Mead, Nebraska, USA, and analyzed the energetics of this agroecosystem by scrutinizing its radiation, energy and entropy exchange. Our results showed: (1) more energy capture during growing season than non-growing season, and increasing energy capture through growing season until senescence; (2) more energy flow activity within and through the system, providing greater potential for degradation; (3) higher efficiency in terms of carbon uptake and water use through growing season until senescence; and (4) the resulting energy degradation occurred at the expense of increasing net entropy accumulation within the system as well as net entropy transfer out to the surrounding environment. Under the drought conditions in 2012, the increased entropy production within the system was accompanied by the enhanced entropy transfer out of the system, resulting in insignificant net entropy change. Drought mitigation with more frequent irrigation shifted the main route of entropy transfer from sensible to latent heat fluxes, yielding the production and carbon uptake exceeding the 12-year mean values at the cost of less efficient use of water and light.

Inhibitory Effect of Steviol and Its Derivatives on Cell Migration via Regulation of Tight Junction-related Protein Claudin 8 (스테비올 및 그 유도체의 세포연접 관련 클라우딘 8 발현 조절을 통한 세포이동 저해효과)

  • Choi, Sun Kyung;Cho, Nam Joon;Cho, Uk Min;Shim, Joong Hyun;Kim, Kee K.;Hwang, Hyung Seo
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.42 no.4
    • /
    • pp.403-412
    • /
    • 2016
  • The tight junction, one of Intercellular junctions, performs a variety of biological functions by bonding adjacent cells, including the barrier function to control the movement of the electrolyte and water. Recent studies have revealed that unusual expression of tight junction-related genes have been shown to be related in cancer development and progression. Recently, there are many reports that control of tight junction proteins expression is closely related to the skin moisture. In this study, we are focusing on the regulating mechanism of tight junction-associated genes by the steviol and its derivatives. Steviol, used as a sweetner, is known to chemical compound isolated from stevia plant. The MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt) assay was carried out in HaCaT cells (human keratinocyte cell line) in order to determine the cytotoxicity. As a result, while steviol showing cytotoxicity from $250{\mu}M$, steviol derivatives are not cytotoxic more than $250{\mu}M$ concentration. We have observed a change in the tight junction protein via quantitative real-time PCR. Claudin 8 among tight junction proteins is only significantly reduced up to 30% in the presence of steviol. In addition, cell migration was inhibited by steviol, not by stevioside and rebaudioside. Finally, we could observe that steviol, not stevioside and rebaudioside, is able to increase the skin barrier permeability through the transepithelial electric resistance (TEER) measurements. These results suggest that the steviol and its derivatives are specifically acts on the tight junction related gene expression, but steviol derivatives are more suitable as a cosmetic material.

THE BONE CHANGES OF THE MIDPALATAL SUTURE AFTER RAPID PALATAL EXPANSION IN YOUNG ADULT DOGS (유성견에서 상악골 급속확장 후 정중구개봉합부에서의 골조직 변화)

  • Park, Chang-Wook;Yoon, Young-Jooh;Kim, Kwang-Won
    • The korean journal of orthodontics
    • /
    • v.27 no.3 s.62
    • /
    • pp.391-399
    • /
    • 1997
  • Rapid palatal expansion(RPE) is a method of inducing the new bone formation in the palate by separation of the midpalatal suture, which can be done conveniently by placing heavy force across the maxillary dental arch. This experiment was undertaken to examine the histologic changes after RPE and during retention period. Four young adult dogs(a control dog, three experimental dogs) aged 4 to 6 months old were used for this experiment. Expansion screw($Hyrax^{\circledR}$, Dentarum Inc.) was delevered to the palate and fumed 180 degrees every morning and evening for 8 days, giving a total expansion of 7.2mm. A control dog was sacrified at the starting point of this study without any treatment and three experimental dogs were sacrified after RPE, 14-day retention, and 28-day retention in each. Thereafter, those samples were observed with hematoxylin-eosin(H-E) stain, ground section(Villanueva stain), alkaline phosphatase(ALP) stain, tartrate-resistant acid phosphatase(TRA) stain. The results were as followings: 1. After RPE, collagen fiber bundles were stretched along the midpalatal suture and few osteoblasts were flattened-inactive state and also, a little osteoid tissues was observed. Few multinucleated osteoclasts which had TRAP-positive activity in their cytoplasm were seen in horizontal section, whereas a few osteoclasts were seen in frontal section, especially in the nasal floor side of palatal bone. 2. After 14-day retention, collagen fiber bundles were stretched along the midpalatal suture and few osteoblasts which had ALP-positive activity in their cytoplasm were seen. Few multinucleated osteoclasts which had TRAP-positive activity in their cytoplasm were seen in horizontal section, whereas a few osteoclasts were seen in frontal section, especially in the nasal floor side of palatal bone. 3. After 28-day retention, collagen fiber bundles were arranged like those of control dog and osteoblasts which showed a lot of immature bone formation were cuboidal shape and exhibited ALP-positive activity in their cytoplasm. Few multinucleated osteoclasts which had TRAP-positive activity in their cytoplasm were seen in horizontal section, whereas a few osteoclasts were seen in frontal section, especially in the nasal floor side of palatal bone. According to the above results, the new bone formation after rapid palatal expansion was examined after 14-day retention and significantly increased after 28-day retention.

  • PDF

pH Stress Alters Cytoplasmic Membrane Fluidity and atpB Gene Expression in Streptococcus mutans (pH stress가 Streptococcus mutans의 형질막 유동성 및 atpB 유전자 발현에 미치는 영향)

  • Cho, Chul Min;Jung, Seung Il;Kim, Myung Sup;Lee, Sae A;Kang, Jung Sook
    • Journal of Life Science
    • /
    • v.27 no.1
    • /
    • pp.15-22
    • /
    • 2017
  • Streptococcus mutans (S. mutans), which plays a major role in the etiology of human dental caries, is able to tolerate exposure to acid shock in addition to its acidogenicity. We investigated the effects of pH stress on membrane fluidity, activities and expression levels of F-ATPase, and proton permeability in S. mutans. Using 1,6-diphenyl-1,3,5-hexatriene, we observed membrane ordering at pH 4.8 and pH 8.8. The ordering effects were larger at pH 4.8 in cytoplasmic membranes isolated from S. mutans (CMSM). Increasing pH resulted in a decrease in the activities and expression levels of F-ATPase. The proton permeability was decreased at both acidic and alkaline pHs, and the lowest permeability was observed at pH 4.8. The lower permeability at pH 8.8 than pH 6.8 is likely to be caused by the decreased proton influx due to the decreased CMSM fluidity. In addition, it seems to be evident that extremely low permeability at pH 4.8 was caused by the decreased proton influx due to the decreased CMSM fluidity as well as the increased proton efflux due to the increased activity and expression level of F-ATPase. It is likely that CMSM fluidity and F-ATPase activity are two major key factors that determine proton permeability in S. mutans. We suggest that CMSM fluidity plays an important role in the determination of proton permeability, which sheds light on the possibility of using nonspecific membrane fluidizers, e.g., ethanol, for anti-caries purposes.

Effects of Depth and Duration of Flooding on Growth and Yield at Flowering Stage in Tomato(Lycopersicon esculentum). (토마토(Lycopersicon esculentum)의 개화기 침수 처리에 따른 생육 반응)

  • Guh, Ja-Ock;Han, Sung-Uk;Kuk, Yong-In;Chon, Sang-Uk;Lee, Young-Man
    • Korean Journal of Environmental Agriculture
    • /
    • v.16 no.2
    • /
    • pp.130-135
    • /
    • 1997
  • Tomatoes are flooded differently 0, 5, 10 and 15cm, according to the developing stages such as flowering stage under the condition of greenhouse. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. Plant height decreased in the depth of $0{\sim}10cm$ for over 48 hours, in the depth of 15cm for over 24 hours. Number of leaves was the same as in control, and it decreased over. Number of flowers and fruit setting of individuals decreased conspicuously according as the depth and the hours got greater and longer. Adventitious root occurred remarkably in the depth of $0{\sim}10cm$, for over 24 hours and in the depth of 15cm, 12 hours. Epinastic curvature increased greatly as the depth and the hours got greater and longer. Diffusion resistance of stomata cell increased as the depth and the hours got greater and longer. Diseases occurred conspicuously as the hours of flooding got longer rather than as the depth greater. The preventing of diseases caused by insecticide was observed, but it was not greater than in the seedling and transplanting stage. Fertilization was effective in the case of increasing the weight of shoot. Number of fruits per plant did not decrease in the depth of 0cm up to 24 hours, but decreased on the deeper level of flooding and increased as the hours got longer. Moreover with the exception of 120 hours per respective depth of the treatment, average weight of a fruit got greater as the depth and the hours got greater and longer. In the case of epinastic curvature and diffusion resistance, there was negative correlation between all the other investigated characters and positive correlation between weight of a fruits and average weight of a fruit.

  • PDF

New Technique for the Reconstruction of Both Anteromedial & Posterolateral Bundles of ACL (전방십자인대의 전내측 다발 및 후외측 다발을 각각 재건하는 새로운 수술 수기)

  • Ha Chul-Won;Awe Soo-Ik
    • Journal of the Korean Arthroscopy Society
    • /
    • v.6 no.2
    • /
    • pp.195-199
    • /
    • 2002
  • This article is to report a new technique for reconstruction of the anteromedial and posterolateral bundles of anterior cruciate ligament by separate tensioning and fixation of the each bundle. Method : Tibial and femoral tunnels were made with conventional technique of anterior cruciate ligament reconstruction. Tibial tunnel was enlarged $5\~7$ mm in anterior-posterior direction to make oval it in cross section. When preparing the Achilles tendon allograft, bone plug portion was trimmed as the conventional technique. The tendinous portion was trimmed as two separate bundles by dividing the tendinous portion longitudinally, so the graft is shaped like 'Y'. The bone plug portion of allograft was inserted into the femoral tunnel and fixed with absorbable cross pins. Two ligamentous portionss of the distal part of the grafts were tensioned separately at the external orifice. Anteromedial bundle was fastened under maximum tension with the knee flexed 90 degrees by post-tie method. The posterolateral bundle was fixed by the same technique with the knee in full extension. Then, an absorbable interference screw was inserted between the two bundles upto the upper end of the tibial tunnel, to get more initial rigidity of the reconstructed graft as well as to locate the two bundles in more anatomic position.

  • PDF

Growth responses to growth hormone therapy in children with attenuated growth who showed normal growth hormone response to stimulation tests (성장호르몬 자극검사가 정상인 성장 장애 소아 환자에게서 성장호르몬 투여에 따른 성장속도의 변화)

  • Kim, Jae-Hyun;Chung, Hye-Rim;Lee, Young-Ah;Lee, Sun-Hee;Kim, Ji-Hyun;Shin, Choong-Ho;Yang, Sei-Won
    • Clinical and Experimental Pediatrics
    • /
    • v.52 no.8
    • /
    • pp.922-929
    • /
    • 2009
  • Purpose : The aim was to investigate the clinical characteristics and responses to growth hormone (GH) therapy in children with attenuated growth who showed normal GH responses to GH stimulation tests (GHST). Methods : The study included 39 patients with height velocity (HV) of less than 4 cm/yr and normal GHST results. Clinical characteristics of patients were analyzed retrospectively. Results : Eleven were born as small for gestational age (SGA) and 28 as appropriate for age (AGA). In the SGA group, the standard deviation score (SDS) of age and height measured at their first visit was significantly low. Sixteen patients were treated with GH and six of 23 without GH therapy were followed for 1 year after GHST. The mean (range) of HV was 7.7 (4.9 to 11.1) cm/yr in patients with GH therapy and 3.7 (2.7 to 4.5) cm/yr in those without GH therapy, which was statistically significant (P<0.001). In the GH-treated group, HV and difference in height SDS during the treatment increased significantly (P<0.001; P< 0.001, respectively). HV increased after 1 year of GH therapy in the SGA and AGA groups (SGA, P=0.043; AGA, P=0.003). The level of Insulin-like growth factor-I was significantly lower in GH-treated patients with height SDS <-3 than those with ${\geq}3$ (P=0.023). Conclusion : In children with growth failure and normal GHST, HV increases significantly by short-term GH therapy. The assessment of long-term effects of GH therapy is necessary. Moreover, further studies should be considered to evaluate the GH-IGF-I axis due to the possibility of GH insensitivity syndrome.

Performance Evaluation of Fabric Sensors for Movement-monitoring Smart Clothing: Based on the Experiment on a Dummy (동작 모니터링 스마트 의류를 위한 직물 센서의 성능 평가: 더미 실험을 중심으로)

  • Cho, Hyun-Seung;Park, Sun-Hyeong;Kang, Da-Hye;Lee, Kang-Hwi;Kang, Seung-Jin;Han, Bo-Ram;Oh, Jung-Hoon;Lee, Hae-Dong;Lee, Joo-Hyeon;Lee, Jeong-Whan
    • Science of Emotion and Sensibility
    • /
    • v.18 no.4
    • /
    • pp.25-34
    • /
    • 2015
  • TThis study explored the requirement of fabric sensor that can measure the motion of the joint effectively by measuring and analyzing the variation in electric resistance of a sensor in accordance with bending and stretching motion of the arm by the implementation of a motion sensor utilizing conductive fabric. For this purpose, on both sides of two kinds of knitted fabric, namely 'L' fabric and 'W' fabric Single Wall Carbon Nano-Tube(SWCNT) was coated, fabric sensor was developed by finishing them in a variety of ways, and the sensor was attached to the arm band. The fabric sensor consisted of total 48 cases, namely background fabric for coating, the method of sensor attachment, the number of layer of sensors, the length of sensor, and the width of sensor. The performance of fabric motion sensors in terms of a dummy arm, that is, a Con-Trex MJ with 48 arm bands around it was evaluated. For each arm band, a total of 48, fastened around the dummy arm, it was adjusted to repeat the bending and stretching at the frequency : 0.5Hz, ROM : $20^{\circ}{\sim}120^{\circ}$, the voltage was recorded for each case after conducting three sets of repeat measurement for a total of 48 cases. As a result of the experiment, and as a consequences of the evaluation and analysis of the voltage based on the uniformity of the base line of the peak-to-peak voltage(Vp-p), the uniformity of Vp-p within the same set, and the uniformity of the Vp-p among three sets, the fabric sensors that have been configured in SWCNT coated 'L' fabric / welding / two layers / $50{\times}5mm$, $50{\times}10mm$, $100{\times}10mm$, and SWCNT coated 'W' fabric / welding / two layers / $50{\times}10mm$ exhibited the most uniform and stable signal value within 5% of the total variation rate. Through all these results of the experiment, it was confirmed that SWCNT coated fabric was suitable for a sensor that can measure the human limb operation when it was implemented as a fabric sensor in a variety of forms, and the optimal sensor types were identified.

A Study on the Changes of Gender Identity Found in the Character of Elsa on Frozen -Focus on Queer Theory- (겨울왕국의 엘사 캐릭터에 나타난 젠더 정체성의 변화 -퀴어이론을 중심으로-)

  • Lee, Jun-Soo
    • Cartoon and Animation Studies
    • /
    • s.38
    • /
    • pp.1-28
    • /
    • 2015
  • The work appeared a featured female character in the Disney animation film begins with 'Snow White' released in 1937. After then, the 11 female characters appeared included 'Tangled' in 2010. Female characters reveal their identity due to obedient, family-oriented and marriage with prince and then gradually develop to heroine who leads to man, and is independent, pioneering, and sometimes saves the nation. Nevertheless, the ending of the Disney animation was still not escape the institutional, traditional discourse. Female characters are followed to meet the featured actor kissing and marriage, or was to show the virtues of sacrifice for the actor. However, Elsa in 'Frozen' is the character with an independent identity compared with the patriarchy, male chauvinism and heterosexual dichotomous discourse given so far in Disney. In this study, it is to explain the change of gender identity in the character of Elsa through Queer theory that deconstructs the distinction between sex and gender, and is constituted by the actions typed and performed the gender concept, and is dismantling the dichotomy itself such as male/female, heterosexual/homosexual. The performative of Queer make the boundaries between lesbian-gay, sexuality and heterosexual ambiguous. It can be said that the performative has political nature resisted to the dominant discourse through these parodiable strategy. The performative showed of Elsa is in the boundaries between the sisterhood and the heterosexual. When analyzed in a heterosexual perspective Elsa's identity is to be understood as simply just love the intimacy of a sister and a sister. On the other hand, if you focused on the relationship between women and the relationship between Elsa and Anna is recognized as the point of view of homosexuality. Because if you look at the concept of lesbian continuum, the homosexual love in the female characters of Disney seems like a bond between women, easier than heterosexual love can be hidden sexual desires. Elsa has developed into a performative identity through the expression of performative and the inhibitory of queer identity. And then the her sorcery that was initially contraindicated and the presence of a fear became to the 'lesbian phallus'. The sorcery that can be seen the signifying phallus against to the privileges of heterosexual patriarchy is recognized in the world of Arendal. Elsa is a new women featuring Disney characters. as this character is analysised by Queer theory, this study seeks to expand the area of the various character analysis methods.