• Title/Summary/Keyword: STRETCHED

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Pulp and periodontal tissue changes following rapid tooth retraction by periodontal distraction in young adult dogs (유성견에서 periodontal distraction에 의한 급속 치아견인 시 치수 및 치주조직의 변화에 관한 연구)

  • Lee, Jong-Jin;Hong, Hyun-Sil;Chae, Jong-Moon;Jo, Jin-Hyung;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.37 no.5
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    • pp.351-363
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    • 2007
  • The aim of this study was to evaluate pulp and periodontal changes following rapid tooth retraction by periodontal distraction after bone undermining surgery in young adult dogs. Methods: Alter extraction of second premolars, the interseptal bone mesial to the upper 3rd premolar was undermined. After activating the distraction appliance at 0.5 mm/day for six days, the dogs were sacrificed at 0, 1, 3, 5, 7, and 9 weeks during the consolidation period. Tissue changes of periodontium and pulp were evaluated radiologically, histologically, and immunohistochemically. Results: Digital subtraction radiography showed active bone formation in the stretched periodontal ligament from 0 - 4 weeks. Resorption of the alveolar bone, appearance of osteoclasts, and infiltration of inflammatory cells were observed just after the activation period at the pressure side, and distinctive bone formation was seen in the tension side of the periodontal ligament from 1 week. New bone formation was active at 1 - 3 weeks. The expression of calcitonin gene-related peptide in the experimental group was increased at the alveolar bone and pulp, and periodontal ligament at the pressure side from 0 - 1 week, and it decreased after 5 weeks to become similar to that of the control group. Conclusions: The results showed that rapid tooth movement using periodontal distraction can be new form of orthodontic tooth movement for accelerating normal bone formation.

Flexible Durability of Ultra-Thin FPCB (초박형 FPCB의 유연 내구성 연구)

  • Jung, Hoon-Sun;Eun, Kyoungtae;Lee, Eun-Kyung;Jung, Ki-Young;Choi, Sung-Hoon;Choa, Sung-Hoon
    • Journal of the Microelectronics and Packaging Society
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    • v.21 no.4
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    • pp.69-76
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    • 2014
  • In this study, we developed an ultra-thin flexible printed circuit board(FPCB) using the sputtered flexible copper clad laminate. In order to enhance the adhesion between copper and polyimide substrate, a NiMoNb addition layer was applied. The mechanical durability and flexibility of the ultra-thin FPCB were characterized by stretching, twisting, bending fatigue test, and peel test. The stretching test reveals that the ultra-thin FPCB can be stretched up to 7% without failure. The twisting test shows that the ultra-thin FPCB can withstand an angle of up to $120^{\circ}$. In addition, the bending fatigue test shows that the FPCB can withstand 10,000 bending cycles. Numerical analysis of the stress and strain during stretching indicates the strain and the maximum von Mises stress of the ultra-thin FPCB are comparable to those of the conventional FPCB. Even though the ultra-thin FPCB shows slightly lower durability than the conventional FPCB, the ultra-thin FPCB has enough durability and robustness to apply in industry.

WRF Numerical Study on the Convergent Cloud Band and Its Neighbouring Convective Clouds (겨울철 동해상의 대상수렴운과 그 주위의 대류운에 관한 WRF 수치모의 연구)

  • Kim, Yu-Jin;Lee, Jae Gyoo
    • Atmosphere
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    • v.24 no.1
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    • pp.49-68
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    • 2014
  • This study analyzed atmospheric conditions for the convergent cloud band (Cu-Cb line) in developing stage and its neighbouring convections formed over the East Sea on 1 February 2012, by using synoptic, satellites data, and WRF numerical simulation output of high resolution. In both satellite images and the WRF numerical simulation outputs, the Cu-Cb line that stretched out toward northwest-southeast was shown in the East Sea, and cloud lines of the L mode were aligned in accordance with the prevailing surface wind direction. However, those of the T mode were aligned in the direction of NE-SW, which was nearly perpendicular direction to the surface winds. The directions of the wind shear vectors connecting top winds and bottom winds of the moist layers of the L mode and the T mode were identical with those of the cloud lines of L mode and T mode, respectively. From the WRF simulation convection circulations with a convergence in the lower layer of atmosphere and a divergence above 1.5 km ASL (Above Sea Level) were identified in the Cu-Cb line. A series of small sized vortexes (maximum vortex: $320{\times}10^{-5}s^{-1}$) of meso-${\gamma}$-scale formed by convergences was found along the Cu-Cb lines, suggesting that Cu-Cb lines, consisting of numerous convective clouds, were closely associated with a series of the small vortexes. There was an absolute unstable layer (${\partial}{\theta}/{\partial}z$ < 0) between sfc and ~0.3 km ASL, and a stable layer (${\partial}{\theta}/{\partial}z$ > 0) above ~2 km ASL over the Cu-Cb line and cloud zones. Not only convectively unstable layers (${\partial}{\theta}_e/{\partial}z$ < 0) but also neutral layers (${\partial}{\theta}_e/{\partial}z{\approx}=0$) in the lower atmosphere (sfc~1.5 km ASL) were scattered around over the cloud zones. Particularly, for the Cu-Cb line there were convectively unstable layers in the surface layer, and neutral layers (${\partial}{\theta}_e/{\partial}z{\approx}=0$) between 0.2 and ~1.5 km ASL over near the center of the Cu-Cb line, and the neutralization of unstable layers came from the release of convective instability.

Localization of the Major Retinal Neurotransmitters and Receptors and Müller Glia in the Retina of the Greater Horseshoe Bat (Rhinolophus ferrumequinum) (한국관박쥐 망막의 신경전달물질 및 수용체, 뮬러세포 동정)

  • Lee, Jun-Seok;Kwon, Oh-Ju;Jeon, Tae-Heon;Jeon, Chang-Jin
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.3
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    • pp.391-396
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    • 2015
  • Purpose: The objective of this study was to investigate the visual system of the greater horseshoe bat (Rhinolophus ferrumequinum) by location analysis of some major neurotransmitters glutamate, ${\gamma}$-aminobutyric acid (GABA), acetylcholine, and their receptors, and $m{\ddot{u}}ller$ glial cells in retina. Methods: Standard immunocytochemical techniques were used after vibratome section of retinal tissues of adult greater horseshoe bat for this study. Immnoreactions in immunofluorescence images were analyzed using confocal microscope. Results: Anti-glutamate-immunoreactive neurons were mainly localized in the ganglion cell layer (GCL). The majority of anti-GABA-immunoreactive cells distributed in the inner nuclear layer (INL), and GABAA receptors were localized in the inner plexiform layer (IPL). Anti-choline acetyltransferase-immuoreactive cholinergic neurons were mainly located in the INL and GCL, and most of nicotinic acetylcholine receptors were localized in the IPL. The $m{\ddot{u}}ller$ cells in the retina of the greater horseshoe bat stretched theirs range from the GCL to outer nuclear layer (ONL). Conclusions: This study revealed that the retinas of the greater horseshoe bats contain the same major neurotransmitters and receptors, and glial cell in visually functional mammalian retinas. The present results may suggest that the greater horseshoe bats have the functional retinas for visual analysis through the organized retinal neural circuits.

A Hand Gesture Recognition System using 3D Tracking Volume Restriction Technique (3차원 추적영역 제한 기법을 이용한 손 동작 인식 시스템)

  • Kim, Kyung-Ho;Jung, Da-Un;Lee, Seok-Han;Choi, Jong-Soo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.6
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    • pp.201-211
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    • 2013
  • In this paper, we propose a hand tracking and gesture recognition system. Our system employs a depth capture device to obtain 3D geometric information of user's bare hand. In particular, we build a flexible tracking volume and restrict the hand tracking area, so that we can avoid diverse problems caused by conventional object detection/tracking systems. The proposed system computes running average of the hand position, and tracking volume is actively adjusted according to the statistical information that is computed on the basis of uncertainty of the user's hand motion in the 3D space. Once the position of user's hand is obtained, then the system attempts to detect stretched fingers to recognize finger gesture of the user's hand. In order to test the proposed framework, we built a NUI system using the proposed technique, and verified that our system presents very stable performance even in the case that multiple objects exist simultaneously in the crowded environment, as well as in the situation that the scene is occluded temporarily. We also verified that our system ensures running speed of 24-30 frames per second throughout the experiments.

Arthroscopic Posterior Capsular Shaft for Traumatic Recurrent Unidirectional Posterior Subluxation of the Shoulder (외상으로 인한 재발성 단방향 견관절 후방 아탈구의 관절경을 이용한 후방낭 이동술)

  • Kim, Seung-Ho;Ha, Kwon-Ick;Yoo, Jae-Chul;Lee, Yong-Seuk;Lee, Hui-Dong
    • Clinics in Shoulder and Elbow
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    • v.6 no.1
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    • pp.55-66
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    • 2003
  • Background: The purpose of this study was to evaluated results of arthroscopic treatment of the traumatic recurrent unidirectional posterior subluxation. Materials and Methods: We treated twenty-seven patients who had traumatic recurrent unidirectional posterior subluxation of the shoulder by arthroscopic labral repair and posterior capsular shift and prospectively evaluated for a mean of thirty-nine months (range,24 to 85 months). Patients who had posteroinferior instability, multidirectional instability, atraumatic onset, or revision cases were excluded. There were twenty-five male and two female patients with the mean age of twenty-one years (range, 14 to 33 years). All patients were involved in sports activity. All had a significant traumatic event prior to the onset of the instability. Stability, motion, three objective measurement (UCLA, ASES, and Rowe scores) and two subjective measurements (pain and function visual analogue scale) were evaluated. Results: The most common finding in magnetic resonance image-arthrogram was separation of the posteroinferior labrum without displacement in 9 patients, In arthroscopic examination, all patients had one or more lesions in the posterior inferior labrum and capsule. The most common finding was incomplete stripping of the posterior inferior labrum (18 patients). The posteroinferior capsule subjectively appeared to be stretched in twenty-two patients. At follow-up, all patients had improved shoulder function and scores(p < 0.01). All patients had stable shoulder by subjectivel and objectivel measurements, except one patient who had recurrent subluxation. All but one patient with postoperative recurrence were able to return to their prior sports activity with little or no limitation. Twenty-four patients were graded as having more than 90% of shoulder function. Their were twenty-one excellent, five good, and one fair UCLA. scores. Pain sore improved from 4.5 to 0.2 point(p : 0.0001). Mean loss internal rotation was one vertebral level. None had operative complications. Conclusion: In conclusion, treatment outcomes of the traumatic unidirectional recurrent posterior subluxation are consistently reliable with respect to the stability, pain relief, and functional restoration by the arthroscopic posterior capsular shift procedure.

An Analysis on the Empathic Changing Process of the Members in Empathy Training Program (공감훈련프로그램 참여아동의 공감표현 변화과정 분석)

  • Kim, Mi-Young
    • The Korean Journal of Elementary Counseling
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    • v.7 no.1
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    • pp.205-226
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    • 2008
  • The purpose of the study you have seen is to verify the effectiveness of existing quantitative research and to put the Empathy Training Program to practical use for participating children. From looking into this, the changes in empathic understanding that came to light in relationships between teacher and children and children and children are sure to have that effect. For this work, I established the following subject of inquiry: What kind of changing processes can be seen in the empathic understanding of participating children in the Empathy Training Program? To resolve the above line of inquiry, six female sixth grade elementary school students were chosen and they progressed through twelve sessions of the Empathy Training Program. The children were given a sentence completion exam, recognition work, neat writing exam and a school adaptation exam both before and after participation in the program, making data for analysis. To analyze, first, participants had one or two meetings of forty to fifty minutes each. Progress through the program's curriculum was recorded and through the repeating and copying method, to be sure participating children's empathic understanding was revealed, empathic language and behavior was routinely chosen. Next, according the above criteria I looked into visible changes of the participating children's empathic expressions, classifying and analyzing changes in empathic understanding and six instances of common changes in the emphatic understanding of the participants relationships were analyzed and put together. Next I will summarize the findings we have seen in this research: First, if we look into changes in common empathic understanding from the beginning, using the criteria of empathic language, each individual showed understanding at the beginning and passed and progressed through stages of care, insight and emotional expressions. Second, when we looked at the criteria of empathic behavior from the beginning to the end, one's line of vision and ability to concentrate one's attention was connected. Next, the act of nodding one's head looked like a brief nod at first but at the end, it was not just a simple nod but rather they could feel deep empathy. The condition and substance of the facial expression was seen to match and at the very end the child was expressive and stretched out arms to hold and pat the other person and the act of holding hands could also be seen. Among lots of empathic behavior the final stage was shown by half of the children. Third, from the first stage to the last stage there were many cases revealed. The more the children went the more complete their empathic language became. Their vocabulary increased and became more diverse with empathic actions. Also, when comparing actions and expressions from the beginning with the end, visible expressions became more natural and sincere at the end. The result of the research we have seen is that through receiving experience of empathic understanding, participating children showed a sense of self-confidence and they looked to make peaceful expressions while not being aggressive or defensive about problems. In addition, from understanding empathic expressions, participating children's relationships felt closer. This outcome within this group in this case will be applied and the formation of empathic understanding can be used by the children internally to solve their own problems, acquire close relationships with their teachers and others. It will also contribute to smooth classroom management.

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Evaluation of Filtration Performance Efficiency of Commercial Cloth Masks (시판되고 있는 유사마스크 제품의 여과효율성능 비교평가)

  • Jang, Ji Young;Kim, Seung Won
    • Journal of Environmental Health Sciences
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    • v.41 no.3
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    • pp.203-215
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    • 2015
  • Objectives: This study was designed to evaluate the filtration efficiencies and pressure drops of five commercial cloth masks (4 plate type, 1 cup type) in comparison to the performance of a class 1 disposable respirator (reference respirator). A further objective was to evaluate the effects of the number of layers and wash treatment independently on filtration efficiencies and pressure drops. Methods: Polydisperse NaCl aerosols were generated in an aerosol chamber and their concentrations were measured by an optical particle counter (OPC) in the size range of $0.3{\sim}10{\mu}m$ (five channels). Results: The filtration efficiencies of the five cloth masks and the reference respirator were D: 9.5%, C: 18.5%, E: 23.6%, A: 28.5%, B: 29.7% and R: 91.1%, respectively, and the pressure drops through them were C, D: 0.8 Pa, E: 1.7 Pa, B: 6.4 Pa, A: 42.7 Pa and R: 19.3 Pa, respectively. The filtration efficiencies of the cloth masks and reference respirator were below the class 1 respirator criterion (${\geq}94.0%$) of the Ministry of Employment and Labor (MOEL) and Ministry of Food and Drug Safety (MFDS). The pressure drops satisfied the class 1 respirator criterion (${\leq}70Pa$) of MOEL and MFDS. When the cloth masks were folded into two and four layers, the filtration efficiencies of cloth masks A, B, C, D (plate type) increased 1.7-4.6 times, and 2.3-6.8 times, respectively, compared to the efficiencies of the same products in a single layer. Pressure drops increased as the number of layers was increased. The filtration efficiency of cloth mask E with a liner was 1.3 times higher than that of the same mask without a liner, and the pressure drop was lower in the no-liner configuration. After a single washing, the filtration efficiencies of all the cloth mask products decreased 1.04-4.0 times compared to those of the same products intact. For the cloth masks C and E, their filtration efficiencies were significantly decreased after washing (p<0.05). The pressure drops of all cloth masks were 1.2-2.0 times lower after washing. Conclusions: The filtration efficiencies of the five cloth masks were below 30% and did not improve greatly by increasing the number of layers. After a single washing, their performances decreased. Considering the above and other issues identified with cloth masks, such as poor fit and stretched fibers through use, people should not expect protection against particulate matters from the cloth masks on the market.

CLINICAL CONSIDERATION ON USING THE ELASTIC 'TIE BACKS' DURING SPACE CLOSURE ('Elastic tie back'을 이용한 발치공간 폐쇄에 관한 임상적 고려)

  • Cho, Ki-Soo;Chun, Youn-Sic
    • The korean journal of orthodontics
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    • v.23 no.2 s.41
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    • pp.217-227
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    • 1993
  • Preadjusted appliance, following the original concept of the Andrews Straight-Wire appliance, became increasingly common in the 1980s. In six phases of treatment, anchorage control, leveling and aligning, overbite control, overjet reduction, space closure, and finishing are very effective with using the preadjusted appliances. Space closure is the phase of treatment in which the difference between standard edgewise and preadjusted mechanics is most noticeable. Orthodontists have been able to reduce the use of closing loops and, because of the level slot lineup, enjoy the advantages of sliding mechanics. In 1990, Dr. John C. Bennett and Richard P. McLaughlin introduced the new space closure system, namely, elastic 'tiebacks'. They found an $.019'\times.025'$ working archwire most effective in an .022'-slot system. Hooks of .024' stainless steel or .028' brass wire are soldered to the upper and lower archwires. The force required for space closure is delivered by elastic 'tiebacks'. An elastic modulo stretched by 2-3mm(to twice its normal length) usually delivers 0.5-1.5mm of space closure per month. Group movement and sliding mechanics are combined for gentle, controlled space closure, so that about 0.5mm of incisor retraction and 0.5mm of mesial molar movement can be seen each month. The tiebacks are replaced every four to six weeks. By using the elastic 'tiebacks', the next two cases were treated during space closure. Even though we found some clinical problems of this mechanics, long treatment time, hard to control of vertical dimension and anchorage, the application method of this system is so simple that orthodontists can manage many patients during short chair time. But we must apply this mechanics after perfect understanding of the biomechanics in tooth movement.

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Congenital Dropsy in Korean-native Calf (한우 송아지의 선천성 전신수종)

  • 강문일;박영석;한동운
    • Korean Journal of Animal Reproduction
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    • v.23 no.1
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    • pp.63-68
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    • 1999
  • A 4-year old Korean-native cow of third parturition delivered an deformed calf with congenital anasarca and hypoplasia of the extremity at Muan County in Chonnam Province. At parturition, the dam showed amniotic fluid approximately two times more than that at the normal and also occurred severe dystocia. The anomaly died before parturition was 82 cm long and weighed 25 kg. It was difficult to recognize the neck and face of the anomaly due to severe edema and the stretched tongue through mouth was found. The shape of the extremity was recognizable and the systemic hypoplasia of the body with marked edema was found. At necropsy, there was a large amount of serous fluid both in pleural and peritoneal cavity. Also the fluid was contained some of yellowish granular materials and diffusely was fulfilled in all subcutaneous tissue. There was a partial opening in diaphragm which was resulted in the protrusion of approximately half of liver toward peritoneal cavity. There were two kidneys (15${\times}$21 and 13${\times}$18 cm) on the left which were enlarged and relatively larger than the right one (13${\times}$9 cm). In addition, there were found slight to moderate hepatomegaly and splenomegaly with slight congestion, and diffuse edema of intestinal serosa. Lung (32${\times}$49 mm) with marked hypoplasia was smaller than the size of heart (56${\times}$45mm). Serological test to the dam showed relatively high antibody titer (>64) to Akabane virus which might be involved in the outbreak of the deformed Korean-native calf as one of many causative agents.

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