• Title/Summary/Keyword: lateral stress

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Analysis of domain required for aggregates formation of ALS (Amyotrophic lateral sclerosis)/FTD (Frontotemporal dementia)-linked FUS in mammalian cells (루게릭병 및 전측두엽성 치매 연관 단백질 Fused in Sarcoma (FUS)의 스트레스 응집체 형성에 관여하는 도메인 분석)

  • Jun, Mi-Hee;Lee, Jin-A
    • Analytical Science and Technology
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    • v.28 no.5
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    • pp.331-340
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    • 2015
  • Mutations in Fused in Sarcoma (FUS) have been identified in patients with amyotrophic lateral sclerosis (ALS) or Frontotemporal Dementia (FTD). Pathological FUS is mis-localized to cytosol and forms aggregates associated with stress granules (SG), while FUS is normally localized to nucleus. However, it is largely unknown how pathological FUS forms SG-aggregates and which domains are responsible for this process. In this study, we examined cellular localization and aggregation of ALS-linked FUS missense mutants (P525L, R521C, R521H, R521G), analyzed the domains responsible for cytosolic FUS aggregation in HEK293T cells, and confirmed this in cultured mouse neurons. To do this, we firstly generated missense mutants of FUS and then examined their cellular localization. We found that P525L was mostly mis-localized to cytosol and formed FUS-positive SG aggregates while R521C, R521H, or R521G was localized to both nucleus and cytosol. To further characterize the domains required for aggregate formation of cytosolic FUS, we generated different domain-deletion mutants using FUS-∆17 which has a deletion of nuclear localization signal. Interestingly, cytosolic FUS without SYGQ and RGG1 domain or cytosolic FUS without RGG2-ZnF-RGG3 domain did not form FUS-positive SG aggregates, while cytosolic FUS without RRM domain generated more aggregates compared to FUS-∆17. Taken together, these data suggest that SYGQ-RGG1 or RGG2-ZnF-RGG3 domain contributes to formation of cytosolic aggregate, while RRM domain might interfere with FUS aggregation. Therefore, our studies will provide important insight for understanding cellular pathogenesis of neurodegeneration associated with FUS aggregate as well as finding therapeutic targets for ALS or FTD.

Clinical Results of Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon (슬괵건을 이용한 전방십자인대 재건술의 임상적 결과)

  • Song Eun Kyoo;Lee Keun Bae;Shin Sang Gyoo;Kim Hyun Jong
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.1 no.1
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    • pp.21-25
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    • 2002
  • Purpose: To evaluate the clinical results after anterior cruciate ligament (ACL) reconstruction with hamstring tendon and Ligament Anchor (LA) screw, which is newly designed for fixation of graft into femur. Materials and Methods: Fifty eight patients who were followed up at least more than 2 years after ACL reconstruction with four strands of Hamstring tendon and LA screw were included in this study. The graft was fixed with LA screw at femoral tunnel and with only bioabsorbable interference screw at tibial tunnel. The mean follow-up period was 28 months. The clinical results were evaluated by physical examination and Lysholm knee score. Widening of bony tunnel and anterior laxity difference compared with normal side by instrumented anterior laxity test with Telos(R) (Telos stress device; Austin & Associates, Inc., Polston, US) were evaluated. Results: The Lysholm knee score improved from 60.0 points preoperatively to 94.0 points at last follow up. On the Lachman test, there were mild (+) instability in 16 cases, moderate (++) in 24,severe (+++) in 18 preoperatively. 50 cases were converted to negative and 8 to mild instability at postoperative follow up. On instrumented anterior laxity test with Telos(R), difference between normal and affected knee on 20 lb was 12.9 mm in average preoperatively, and was decreased to 3.1mm at last follow-up. The femoral tunnel was widened from 10.6 mm postoperatively to 12.7 mm (21.1$\%$) at follow up on antero-posterior plane and from 10.7 mm to 12.4 mm (16.5$\%$) on lateral plane. Tibial tunnels was also widened from 9.8mm to 11.8mm (20.7$\%$) on antero-posterior plane and from 9.9mm to 11.7 mm ($18.9\%$) on lateral plane. Complications were: anterior knee crepitus in 17 case, quadriceps muscle atrophy(>3 cm) in 6, penetration of screw over the lateral femoral cortex in 5, saphenous nerve paresthesia in 2.Conclusions: ACL reconstruction with hamstring tendon and LA screw was one of the choice of grafts and fixation devices in restoring knee stability and in improving clinical results with little complications such as excessive widening of bony tunnel and anterior knee pain

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Improved Degradation Characteristics in n-TFT of Novel Structure using Hydrogenated Poly-Silicon under Low Temperature (낮은 온도 하에서 수소처리 시킨 다결정 실리콘을 사용한 새로운 구조의 n-TFT에서 개선된 열화특성)

  • Song, Jae-Ryul;Lee, Jong-Hyung;Han, Dae-Hyun;Lee, Yong-Jae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.105-110
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    • 2008
  • We have proposed a new structure of poly-silicon thin film transistor(TFT) which was fabricated the LDD region using doping oxide with graded spacer by etching shape retio. The devices of n-channel poly-si TFT's hydrogenated by $H_2$ and $HT_2$/plasma processes are fabricated for the devices reliability. We have biased the devices under the gate voltage stress conditions of maximum leakage current. The parametric characteristics caused by gate voltage stress conditions in hydrogenated devices are investigated by measuring /analyzing the drain current, leakage current, threshold voltage($V_{th}$), sub-threshold slope(S) and transconductance($G_m$) values. As a analyzed results of characteristics parameters, the degradation characteristics in hydrogenated n-channel polysilicon TFT's are mainly caused by the enhancement of dangling bonds at the poly-Si/$SiO_2$ interface and the poly-Si Brain boundary due to dissolution of Si-H bonds. The structure of novel proposed poly-Si TFT's are the simplity of the fabrication process steps and the decrease of leakage current by reduced lateral electric field near the drain region.

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A Study on Properties of Mechanical Behaviors of Concrete Confined by Circular Steel Tube (원형강관으로 구속된 콘크리트의 역학적 거동 특성에 관한 연구)

  • 박정민;김화중
    • Magazine of the Korea Concrete Institute
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    • v.7 no.3
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    • pp.199-210
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    • 1995
  • We could say that the concrete filled steel tube structure is superior in the vlew of various structure properties as to promote improvement of structural capacity to dtmonstrate heterogeneous material properties interdependently. The compressive strength is increased by putting to tri axial stress because lateral expansion of concrete 1s confined by the steel tube, when concrete conflned by steel tube fall under centric axial load. Also, it have an advantage that decreasr of load carrying capacity 1s small, not occuring section deficiency due to protect falling piienornonon by co~nprrssion fallurc of concrete. So this study investigated for structural behaviors yroprrtiex of concwir. confined by steel tube throughout a series of experlmerit with kcy parxncter, such as diameter-to-thickness(D / t) ratio, strength of concrete as a study on properties of structural behaviors of confined concrete confined by circular steel tube( tri axial stress). Frorn the expcrment results, the obtained results, are surnrnarised as foliow. (1) The restraint effect of concrete by steel tube was presented significantly as the D /t ratio of steel tube and the strength of filled concrete decrease, and the confined concrete by circular steel tube was increased respectively twice as much as 4-7 in deformation capacity at the ultimate strength ,compared with those of non-confined concrete, so expected to increase flexible effect of concrete. (2) The emprical formula to predict the ultimate capacity of confined concrete by steel tube and concrete filled steel tube column using restraint coefficient of concrete were proposed.

Finite Element Analysis for Investigating the Behavior of Gravel Compaction Pile Composite Ground (GCP 복합지반의 거동분석을 위한 유한요소해석)

  • Kim, Gyeong-eop;Park, Kyung-Ho;Kim, Ho-Yeon;Kim, Daehyeon
    • Journal of the Korean Geosynthetics Society
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    • v.17 no.3
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    • pp.19-32
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    • 2018
  • Gravel Compaction Pile (GCP) method is currently being designed and constructed by empirical method because quantitative design method has not been developed, leading to various types of and frequent destruction such as expansion failure and shear failure and difficulties in establishing clear cause and developing measure to prevent destruction. In addition, despite the difference with domestic construction equipment and material characteristics, the methods applied to the overseas ground is applied to the domestic as it is, leading to remarkable difference between applied values and measured values in variables such as bearing capacity and the settlement amount. The purpose of this study was, therefore, to propose a reasonable and safe design method of GCP method by analyzing the settlement and stress behavior characteristics according to ground strength change under GCP method applied to domestic clay ground. For the purpose, settlement amount of composite ground, stress concentration ratio, and maximum horizontal displacement and expected location of GCP were analyzed using ABAQUS. The results of analysis showed that the settlement and Settlement reduction rate of composite ground decreased by more than 60% under replacement ratio of 30% or more, that the maximum horizontal displacement of GCP occurred at the depth 2.6 times pile diameter, and that the difference in horizontal displacement is slight under replacement ratio of 30%.

Finite Element Stress Analysis of Implant Prosthesis of Internal Connection System According to Position and Direction of Load (임플랜트-지대주의 내측연결 시스템에서 하중의 위치 및 경사에 따른 임플랜트 보철의 유한요소 응력분석)

  • Jang, Jong-Seok;Jeong, Yong-Tae;Chung, Chae-Heon
    • Journal of Dental Rehabilitation and Applied Science
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    • v.21 no.1
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    • pp.1-14
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    • 2005
  • The purpose of this study was to assess the loading distributing characteristics of implant prosthesis of internal connection system(ITI system) according to position and direction of load, under vertical and inclined loading using finite element analysis (FEA). The finite element model of a synOcta implant and a solid abutment with $8^{\circ}$ internal conical joint used by the ITI implant was constructed. The gold crown for mandibular first molar was made on solid abutment. Each three-dimensional finite element model was created with the physical properties of the implant and surrounding bone. This study simulated loads of 200N at the central fossa in a vertical direction (loading condition A), 200N at the outside point of the central fossa with resin filling into screw hole in a vertical direction (loading condition B), 200N at the centric cusp in a $15^{\circ}$ inward oblique direction (loading condition C), 200N at the in a $30^{\circ}$ inward oblique direction (loading condition D) or 200N at the centric cusp in a $30^{\circ}$ outward oblique direction (loading condition E) individually. Von Mises stresses were recorded and compared in the supporting bone, fixture, and abutment. The following results have been made based on this study: 1. Stresses were concentrated mainly at the ridge crest around implant under both vertical and oblique loading but stresses in the cancellous bone were low under both vertical and oblique loading. 2. Bending moments resulting from non-axial loading of dental implants caused stress concentrations on cortical bone. The magnitude of the stress was greater with the oblique loading than with the vertical loading. 3. An offset of the vertical occlusal force in the buccolingual direction relative to the implant axis gave rise to increased bending of the implant. So, the relative positions of the resultant line of force from occlusal contact and the center of rotation seems to be more important. 4. In this internal conical joint, vertical and oblique loads were resisted mainly by the implant-abutment joint at the screw level and by the implant collar. Conclusively, It seems to be more important that how long the distance is from center of rotation of the implant itself to the resultant line of force from occlusal contact (leverage). In a morse taper implant, vertical and oblique loads are resisted mainly by the implant-abutment joint at the screw level and by the implant collar. This type of implant-abutment connection can also distribute forces deeper within the implant and shield the retention screw from excessive loading. Lateral forces are transmitted directly to the walls of the implant and the implant abutment mating bevels, providing greater resistance to interface opening.

A 3-D finite element analysis on the mandibular movement pattern and stress distribution during symphyseal widening (하악 이부확장 시 하악골 이동 양상과 응력 분포에 관한 삼차원 유한요소법적 연구)

  • Lee, Do-Hoon;Hong, Hyun-Sil;Chae, Jong-Moon;Jo, Jin-Hyung;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.38 no.1
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    • pp.13-30
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    • 2008
  • Objective: The objective of this study was to evaluate the displacement pattern and the stress distribution of the finite element model 3-D visualization during symphyseal widening according to the osteotomy position, osteotomy type, and distraction device. Methods: The kinds of distraction devices used were tooth-borne type, hybrid type, bone-borne type and tooth-borne type $30^{\circ}$ angulated, and the kinds of osteotomy design were vertical osteotomy line between the central incisors and step osteotomy line through the symphysis. Results: All reference points of the mandible including the condyles were displaced laterally irrespective of the osteotomy position, osteotomy method and distraction device. The anteroposterior or vertical displacements showed small differences between the groups. The widening pattern of the osteotomy line in the tooth-borne type of device was v shaped, and that of bone-borne type was a reverse v shape. However, the pattern in the hybrid type was parallel. The lateral displacement of the mandibular angle by the bone-borne device was more remarkable than the other types of devices. The displacement by the $30^{\circ}$ angulated tooth-borne type was different between the left and right sides in both the transverse and anteroposterior aspects. Conclusion: The design of the distraction devices and osteotomy line can influence the displacement pattern and the stress distribution during mandibular symphyseal distraction osteogenesis procedures.

A PHOTOELASTIC STRESS ANLYSIS IN THE SURROUNDING TISSUES OF TEETH SEATED BY INDIRECT RETAINERS WHEN APPLIED DISLODGING FORCES ON UNILATERAL DISTRAL EXTENTION PARTIAL DENTURES (편측성 후방연장 국소의치의 의치상에 이탈력이 가해질 때 간접유지장치가 장착된 치아 주위조직에 발생하는 응력에 관한 광탄성 분석)

  • Son, Jee-Young;Lee, Cheong-Hee;Jo, Kwang-Hun
    • The Journal of Korean Academy of Prosthodontics
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    • v.34 no.3
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    • pp.415-430
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    • 1996
  • The purpose of this study was to evaluate the stress distributions in the surrounding tissues of the teeth seated by indirect retainers in three different teeth of unilateral distal extension partial denture when the dislodging forces were applied on denture bases. Three dimensional photoelastic models were made. The teeth on which indirect retainers were seated were mandibular left lateral incisor (Model I), canine (Model II), and first premolar (Model III). The dislodging force with 860mg at $45^{\circ}$ angulation to occlusal plane was applied to each model. Three dimensional photoelastic stress analysis was done, and the records were diagramed and analysed. The results were as follows : The compressive stresses were shown the most on neck portions of buccal, mesial, and distal sides in all three models. Slight tensile stresses were shown on neck portions of lingual sides in all three models. The compressive stresses on buccal side were shown in strength in such order as model I, model II, and model III. The compressive stresses were shown on neck portion of mesial and distal sides of model I and mode II, with model I more than Model II. The compressive stresses were shown only on neck portion of mesial side on Model III. The general overall magnitude of compressive stresses were shown in strength in such order as Model I, Model II, and Model III.

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Behaviors of Soft Bangkok Clay behind Diaphragm Wall Under Unloading Compression Triaxial Test (삼축압축 하에서 지중연속벽 주변 방콕 연약 점토의 거동)

  • Le, Nghia Trong;Teparaksa, Wanchai;Mitachi, Toshiyuki;Kawaguchi, Takayuki
    • Journal of the Korean Geotechnical Society
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    • v.23 no.9
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    • pp.5-16
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    • 2007
  • The simple linear elastic-perfectly plastic model with soil parameters $s_u,\;E_u$ and n of undrained condition is usually applied to predict the displacement of a constructed diaphragm wall(DW) on soft soils during excavation. However, the application of this soil model for finite element analysis could not interpret the continued increment of the lateral displacement of the DW for the large and deep excavation area both during the elapsed time without activity of excavation and after finishing excavation. To study the characteristic behaviors of soil behind the DW during the periods without excavation, a series of tests on soft Bangkok clay samples are simulated in the same manner as stress condition of soil elements happening behind diaphragm wall by triaxial tests. Three kinds of triaxial tests are carried out in this research: $K_0$ consolidated undrained compression($CK_0U_C$) and $K_0$ consolidated drained/undrained unloading compression with periodic decrement of horizontal pressure($CK_0DUC$ and $CK_0UUC$). The study shows that the shear strength of series $CK_0DUC$ tests is equal to the residual strength of $CK_0UC$ tests. The Young's modulus determined at each decrement step of the horizontal pressure of soil specimen on $CK_0DUC$ tests decreases with increase in the deviator stress. In addition, the slope of Critical State Line of both $CK_0UC$ and $CK_0DUC$ tests is equal. Moreover, the axial and radial strain rates of each decrement of horizontal pressure step of $CK_0DUC$ tests are established with the function of time, a slope of critical state line and a ratio of deviator and mean effective stress. This study shows that the results of the unloading compression triaxial tests can be used to predict the diaphragm wall deflection during excavation.

A comparison between the modified Brostrom procedure using single and double suture anchor for chronic lateral ankle instability (발목관절 외측 불안정성에서 단일 봉합나사와 이중 봉합나사를 이용한 변형 Brostrom 술식간의 임상결과 비교)

  • Shon, Hyun-Chul;Cho, Byung-Ki;Kim, Yong-Min;Kim, Dong-Soo;Choi, Eui-Sung;Park, Kyoung-Jin;Park, Ji-Kang
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.10 no.2
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    • pp.69-77
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    • 2011
  • Purpose: This study was retrospectively performed to compare the clinical outcomes of modified Brostrom procedures using the single suture anchor and the double suture anchor for chronic lateral ankle instability. Materials and Methods: Thirty-seven patients were followed up for more than 1 year after the modified Brostrom procedures using suture anchor. Single surgeon treated seventeen cases with single suture anchor and 20 cases with double suture anchor. The clinical evaluation was performed according to the Karlsson scale and Sefton grading system. Radiologic measurement of the talar tilt and anterior talar translation was performed through anterior and varus stress radiographs using Telos device. Results: The Karlsson scale had improved significantly from preoperative average of 45.2 points to 89.4 points in single suture anchor group, and from 46.4 points to 90.5 points in double suture anchor group. According to the Sefton grading system, 15 cases (88.2%) in single suture anchor group and 18 cases (90%) in double suture anchor group achieved satisfactory results. The talar tilt angle and anterior talar translation had improved significantly from preoperative average of $13.6^{\circ}$ and 8.6 mm to $5.4^{\circ}$ and 4.1 mm in single suture anchor group, from $14.1^{\circ}$ and 8.4mm to $3.9^{\circ}$ and 4 mm in double suture anchor group. Double suture anchor technique was significantly superior in postoperative talar tilt. Conclusion: Single and double suture anchor techniques produced similar clinical and functional outcomes except for talar tilt, which was significantly superior in double suture anchor group. Both modified Brostrom procedures using the single and double suture anchor appear to be effective treatment methods for chronic lateral ankle instability. Further evaluation of clinical outcomes and biomechanical studies in athletes are needed.

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