• Title/Summary/Keyword: Lower head failure

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The Solderability and Mechanical Properties of In, Bi Added Sn-9Zn/Cu Joint (In, Bi가 첨가된 Sn-9wt.%Zn/Cu 접합부의 납땜성 및 기계적 성질)

  • Baek, Dae-Hwa;Lee, Kyung-Ku;Lee, Doh-Jae
    • Journal of Korea Foundry Society
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    • v.20 no.2
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    • pp.116-121
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    • 2000
  • Interfacial reaction and mechanical properties between Sn-Zn-X ternary alloys(X : 3wt.%In, 4wt.%Bi) and Cu-substrate were studied. Cu/solder joints were subjected to aging treatments for up to 50days to see interfacial reaction at $100^{\circ}C$ and then were examined changes of microstructure and interfacial compound by optical microscopy, SEM and EDS. Cu/solder joints were aged to 30days and then loaded to failure at cross head speed of 0.3 mm $min^{-1}$ to measure tensile strength. According to the results of the solderability test, additions of In and Bi in the Sn-9wt.%Zn solder improve the wetting characteristics of the alloy and lower the melting temperature. Through the EDS and XRD analysis of Cu/Sn-9wt.%Zn solder joint, it was concluded that the intermetallic compound was the ${\gamma}-Cu_5Zn_8$ phase. Cu-Zn intermetallics at Cu/solder interfaces played an important role in both the microstructure evolution and failure of solder joints. Cu/solder joint strength was decreased by aging treatment, and those phenomenon was closely related to the thickening of intermetallic layer at Cu/solder joints.

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LINE-1 and Alu Methylation Patterns in Lymph Node Metastases of Head and Neck Cancers

  • Kitkumthorn, Nakarin;Keelawat, Somboon;Rattanatanyong, Prakasit;Mutirangura, Apiwat
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4469-4475
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    • 2012
  • Background: The potential use of hypomethylation of Long INterspersed Element 1 (LINE-1) and Alu elements (Alu) as a biomarker has been comprehensively assessed in several cancers, including head and neck squamous cell carcinoma (HNSCC). Failure to detect occult metastatic head and neck tumors on radical neck lymph node dissection can affect the therapeutic measures taken. Objective: The aim of this study was to investigate the LINE-1 and Alu methylation status and determine whether it can be applied for detection of occult metastatic tumors in HNSCC cases. Methods: We used the Combine Bisulfite Restriction Analysis (COBRA) technique to analyse LINE-1 and Alu methylation status. In addition to the methylation level, LINE-1 and Alu loci were classified based on the methylation statuses of two CpG dinucleotides in each allele as follows: hypermethylation ($^mC^mC$), hypomethylation ($^uC^uC$), and 2 forms of partial methylation ($^mC^uC$ and $^uC^mC$). Sixty-one lymph nodes were divided into 3 groups: 1) non-metastatic head and neck cancer (NM), 2) histologically negative for tumor cells of cases with metastatic head and neck cancer (LN), and 3) histologically positive for tumor cells (LP). Results: Alu methylation change was not significant. However, LINE-1 methylation of both LN and LP was altered, as demonstrated by the lower LINE-1 methylation levels (p<0.001), higher percentage of $^mC^uC$ (p<0.01), lower percentage of $^uC^mC$ (p<0.001) and higher percentage of $^uC^uC$ (p<0.001). Using receiver operating characteristic (ROC) curve analysis, $%^uC^mC$ and $%^mC^uC$ values revealed a high level of AUC at 0.806 and 0.716, respectively, in distinguishing LN from NM. Conclusion: The LINE-1 methylation changes in LN have the same pattern as that in LP. This epigenomic change may be due to the presence of occult metastatic tumor in LN cases.

Microsurgical Reconstruction in Elderly Patients (노인에서의 미세수술에 의한 재건술)

  • Jun, Myung Gon;Park, Bong Kweon;Ahn, Hee Chang
    • Archives of Reconstructive Microsurgery
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    • v.9 no.1
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    • pp.1-5
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    • 2000
  • The microsurgical reconstruction is necessary for elderly patients to treat severe trauma and head and neck tumor. The aim of this study is to analyze the risks of microvascular surgery and whether or not happening of more complication in elderly patients who are older than 60 years old and to suggest the solution of the complication. The retrospective study included 41 elderly patients who underwent treatment of 44 microsurgical reconstructions among total 271 cases of microsurgical reconstruction from July, 1988 to December, 1998. Their ages ranged from 61 years to 79 years. There were 26 males and 15 females. The involved sites were 23 head and necks, 13 upper gastrointestinal tracts, 3 lower extremities, 1 chest and 1 sacral region. The causes of microsurgical reconstruction were 36 head and neck tumors, 2 radionecrosis, 2 traumas and 1 melanoma in lower limb. The used flaps were 14 radial forearm flaps, 13 jejunal flaps, 10 latissimus dorsi muscle flaps, 3 rectus abdominis muscle flaps, 2 lateral arm flaps, 1 scapular flap, and 1 iliac osteocutaneous flap. They had medical problems which were 29 tobacco abuse, 14 hypertensions, 13 alcohol abuse, 10 chronic obstructive pulmonary diseases, 7 diabetes mellituses, 3 ischemic heart diseases. All patients have had successful results without specific complications except 3 cases of free flap failure and 3 perioperative death. The causes of 3 flap failures were 2 flap necrosis due to arterial insufficiency and 1 flap loss due to secondary infection. All of these cases were treated with secondary free flap surgery. However 3 patients died perioperatively due to 2 respiratory arrests and 1 sepsis. It was not related to operate microsurgical reconstruction itself, but was correlated with the complication of postoperative care after head and neck surgery. We conclude that plastic surgeons consider the importance of prevention of expected complication as thorough analysis of operative risk factor and appropriate treatment. We had to select the donor and recipient vessel appropriately to perform successful microsurgery in elderly patients and consider vein graft and end-to-side anastomosis to reduce complication if necessary. In addition, we emphasize the importance of pre, peri and postoperative care in head and neck cancer patients to reduce postoperative complication and morbidity.

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The Effects of Radiotherapy for Oropharyngeal Cancer ; A Single Institutional Experience (구인두 암에서 방사선 치료의 효과 ; 단일기관의 경험)

  • Choi, Euncheol;Kim, Ok Bae;Oh, Young Kee;Kim, Mi Young;Yeo, Chang Ki;Byun, Sang Jun;Park, Seung Gyu;Kim, Jin Hee
    • Korean Journal of Head & Neck Oncology
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    • v.30 no.2
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    • pp.62-67
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    • 2014
  • Background and Objectives : To investigate the prognostic factors and effectiveness of radiotherapy for oropharyngeal cancer. Material and Methods : Forty seven patients in oropharyngeal cancer treated with radiotherapy between November 1989 and October 2010. Conventional radiotherapy was performed until July 2007 and conformal radiotherapy was performed since August 2007. Median age of patients was 59. Thirty five patients were males. Nine patients had operation. Patients treated with postoperative radiotherapy were delivered median 60 Gy and patients treated with definitive radiotherapy were delivered median 66 Gy. Median follow-up periods were 51 months. Results : Two year and 5 year overall survival rate was 78.7% and 59.9%. Two year and 5-year locoregional recurrence free survival rate was 82.3% and 72.9%. In subgroup of definitive radiotherapy, at univariate analysis for overall survival, lower N stage(p=0.01), lower stage(p=0.05) and well and moderate differentiation(p=0.001) were statistically significant. At univariate analysis for locoregional recurrence free survival, lower T stage(p=0.02) and better differentiation(p=0.043) were statistically significant. Treatment failure occurred in 12 patients. Locoregional recurrence(8 patients) was main pattern of failure. Conclusion : When definitive radiotherapy compared with postoperative adjuvant radiotherapy, there was no significant difference. Further studies would be needed to compare definitive radiotherapy with postoperative radiotherapy. N stage, stage and differentiation could be the prognostic factors for overall survival and T stage and differentiation could be the prognostic factors for locoregional recurrence free survival in patients treated definitive radiotherapy.

A Case of Henoch-Sch$\"{o}$nlein Purpura with Acute Pancreatitis and Hypovolemic Acute Renal Failure (급성 췌장염과 저혈량성 급성 신부전이 동반된 Henoch-Sch$\"{o}$nlein 자반증 1예)

  • Oh, Ki-Won;Park, Sang-Kyu;Kim, Joon-Sung
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.2
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    • pp.226-229
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    • 2009
  • Gastrointestinal involvement in Henoch-Sch$\"{o}$nlein purpura (HSP) is common. However, both acute pancreatitis and acute renal failure appear to be very rare complications of HSP. We describe a case of HSP with acute pancreatitis and hypovolemic acute renal failure in a 7-year-old girl who presented with a vasculitic purpuric rash involving the lower extremities, abdominal pain, hematochezia, vomiting, and oliguria. Laboratory findings showed increased serum levels of amylase, lipase, and creatinine. An abdominal CT scan revealed diffuse enlargement of the head and body of the pancreas. The patient was successfully managed with conservative treatment, including corticosteroids, and then her pancreatic enzymes and renal function returned to normal. Acute pancreatitis should be differentiated from other causes of acute abdomen in HSP to avoid unnecessary surgery.

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CSPACE for a simulation of core damage progression during severe accidents

  • Song, JinHo;Son, Dong-Gun;Bae, JunHo;Bae, Sung Won;Ha, KwangSoon;Chung, Bub-Dong;Choi, YuJung
    • Nuclear Engineering and Technology
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    • v.53 no.12
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    • pp.3990-4002
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    • 2021
  • CSPACE (Core meltdown, Safety and Performance Analysis CodE for nuclear power plants) for a simulation of severe accident progression in a Pressurized Water Reactor (PWR) is developed by coupling of verified system thermal hydraulic code of SPACE (Safety and Performance Analysis CodE for nuclear power plants) and core damage progression code of COMPASS (Core Meltdown Progression Accident Simulation Software). SPACE is responsible for the description of fluid state in nuclear system nodes, while COMPASS is responsible for the prediction of thermal and mechanical responses of core fuels and reactor vessel heat structures. New heat transfer models to each phase of the fluid, flow blockage, corium behavior in the lower head are added to COMPASS. Then, an interface module for the data transfer between two codes was developed to enable coupling. An implicit coupling scheme of wall heat transfer was applied to prevent fluid temperature oscillation. To validate the performance of newly developed code CSPACE, we analyzed typical severe accident scenarios for OPR1000 (Optimized Power Reactor 1000), which were initiated from large break loss of coolant accident, small break loss of coolant accident, and station black out accident. The results including thermal hydraulic behavior of RCS, core damage progression, hydrogen generation, corium behavior in the lower head, reactor vessel failure were reasonable and consistent. We demonstrate that CSPACE provides a good platform for the prediction of severe accident progression by detailed review of analysis results and a qualitative comparison with the results of previous MELCOR analysis.

Consideration for therapy method and oral motor function character of children with cerebral palsy (뇌성마비 아동의 구강운동 기능 특성 및 치료방법에 관한 고찰)

  • Lim, Hyoung-Won
    • Journal of Korean Physical Therapy Science
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    • v.13 no.2
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    • pp.121-127
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    • 2006
  • Consideration for therapy method and oral motor function character of children with cerebral palsy. Therapists who treat for feeding disorder children owing the regression of oral motor function are necessary to gain knowledge about dysfunction of sensing, perception and cognition with baffling to eat and inhibition of primitive reflex, oral anatomy and function, and motor control (trunk, head, positioning of the upper limbs and the lower limbs and muscle tone). Oral motor function program is a comprehensive rehabilitation program which requires systematized enforcement and collaborated attempts to physiotherapists, occupational therapists, speech therapists, psychotherapists. Especially, physical therapists are not accustomed to oral motor program, hoping to provide diffusely and apply new therapy approach method for many areas (bell's palsy, respiratory failure, speech articulation). It will comprise to study owing to holistic approach with clinic.

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Reconstruction of Hypopharynx and Cervical Esophagus : Choice of Flap (하인두 및 경부식도 결손의 재건 : 재건술의 선택)

  • Choi Eun-Chang;Lee Sei-Young;Chung Tae-Young;Kim Se-Heon;Kim Young-Ho;Ryu Dae-Hyun;Kim Choong-Bae
    • Korean Journal of Head & Neck Oncology
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    • v.16 no.1
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    • pp.26-32
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    • 2000
  • Background and Objectives: Various flaps are using for reconstruction of hypopharyngeal and esophageal defect. However, complication and indication of each flap are not fully analyzed. Patient and Methods: Records of 52 hypopharyngeal cancer patients who had surgical treatment and 13 other head and neck cancer patients who underwent hypopharyngeal and/or esophageal reconstruction with flap were retrospectively analyzed. Eighty three percent(54 cases) of patients needed reconstruction other than primary pharyngeal closure. Five split thickness skin graft, 1 pectoralis major myocutaneous flap, 20 forearm free flap, 13 jejunal free flap, 15 gastric pull up were used. Result: Flap failure was noted in 2 cases who had subsequent gastric transposition. Wound dehiscence and fistula were most common problem of forearm free flap. Most fistulas were developed in patients with conduit type reconstruction of forearm flap while there wasn't any fistula in patient with patch type reconstruction. Stenosis of lower anastomosis was the frequent problem of jejunal transfer. Gastric pull-up has frequent com-plication of stomal stenosis. All but three patients had reached oral feeding postoperatively. Conclusion: Based on this study, forearm flap is effective in partial hypopharyngeal defect while jejunum is the choice for circumferential defect. Gastric pull-up is for combined esophageal defect.

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A Study on the Decondensation and Pronucleus Formation of Sperm Nucleus in the Mouse Oocyte

  • Kang, Hee-Gyoo;Kim, Tai-Jeon;Bae, Hyung-Joon;Moon, Hi-Joo;Lee, Ho-Joon;Yang, Hye-Young;Kim, Moon-Kyoo
    • Biomedical Science Letters
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    • v.7 no.4
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    • pp.173-179
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    • 2001
  • To investigate the ability to decondense sperm head penetrated into cytoplasm of the oocytes and the relationship between this ability and the level of glutatione (GSH) in mouse oocyte at various maturing stages. The fertilizability of oocytes at various stages of maturation the decondensation of sperm nucleus and the formation of male pronucleus, were observed and the levels of GSH were measured in oocyte at same stages. Besides, the relation between fertilizability and level of GSH in oocyte cytoplasm treated with L-buthionine-S, R-sulfoxmine (L-BSO), the inbitor of biosynthesis of GSH, was determined. The decondensation of sperm head was not found in GV stage and L-BSO treated oocytes. In maturing oocytes (GVBD, MI), the decondensation was found, but the formation of male pronucleus was not. The levels of GSH in oocyte cytoplasm were measured; 2.2 pmol per oocyte in the ovulated and the matured in vitro each, 1.0 pmol in GV intact oocyte, 1.3 pmol in GVBD, and 1.5 pmol in MI phase oocyte. In L-BSO treated oocytes the levels of CSH were measured 0.08~o.09 pmol per oocyte, slightly lower than GV stage oocyte. In conclusion, GSH in oocyte is supposed to be synthesized and storaged in cytoplasm during maturation. The failure of decondensation in the cytoplasm of GV stage and L-BSO treated is suggested that GSH is an essential factor in decondensing the sperm head and that the a certain level of GSH, more than in GV oocyte cytoplasm, is required in decondensation.

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Enhancing Shoulder External Rotator Electromyography Activity During Sitting External Rotation Exercise: The Impact of Biofeedback Training

  • Il-young Yu;Min-joo Ko;Jae-seop Oh
    • Physical Therapy Korea
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    • v.30 no.3
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    • pp.237-244
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    • 2023
  • Background: The external rotation (ER) exercise in performed at a 90° abduction of the shoulder joint is an effective to strengthen the infraspinatus. However, failure of the humeral head to control axial rotation during exercise can be increased the posterior deltoid over activity. Biofeedback training is an effective method of promoting motor learning and control it could look forward to activate the infraspinatus selectively by controlling the humeral head during exercise. Objects: The aim of this study was investigated that whether biofeedback for axial rotation was effective to activate selectively the infraspinatus during ER exercise. Methods: The 15 healthy males participated, and all subjects performed both ER exercise in a sitting position with shoulder abducted 90° under conditions with and without axial rotation biofeedback. Exercise was performed in a range of 90° ER, divided into three phases: concentric, isometric, and eccentric. The infraspinatus and posterior deltoid muscle activity were observed using surface electromyography. Results: Both infraspinatus activity (p < 0.01) and infraspinatus to posterior deltoid activity ratio (p = 0.01) were significantly higher with biofeedback however, posterior deltoid activity was significantly lower with biofeedback (p = 0.01). The infraspinatus muscle activity and muscle activity ratio were the highest in the isometric contraction type, and there were significant differences for all contraction types (p < 0.05). Whereas, the posterior deltoid activity was the lowest in the isometric contraction type, and showed a significant difference between isometric and other two contraction types (p < 0.05), but no significant different between concentric and eccentric contraction. Conclusion: Our results indicate that the axial rotation biofeedback during sitting ER exercise might be effective method to activating selective infraspinatus muscle and recommended to enhance the dynamic stability of the shoulder joint.