초경합금 소재 LCU_CL 코어의 초정밀 연삭 특성에 관한 연구

정상화,차경래,김현욱,이봉주 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

As the various manufacturing technology of optical glass is developed, the aspherical lenses are applied to many fields. However, It is still very difficult to manufacture glass lens because of the high cost and the short life of core. In recent years, the demands of the aspherical glass lenses increase since it is difficult to obtain the desirable performance in the plastic lens. In the glass mold lens, it has merits of high productivity and reproductivity since lens is manufactured by the only forming with high precision mold. The fabricating conditions for glass mold lens are glass surface that does not cause fusion, viscosity of 108-1013 poise for the 0.2㎛ accuracy, and viscoelasticity for the roughness less than 100 angstrom. In this thesis, ultra-precision grinding characteristics of tungsten carbide for forming the aspherical glass lens core were studied and the result of it is applied to manufacture the tungsten carbide-base core of the glass lens used to the laser scanning unit and the camera phone.

RO 및 NF막에서의 부식질에 의한 Fouling 및 미량오염물질의 제거

왕창근,차준철,이용현,김수동,류주환 대한상하수도학회 2004 상하수도학회지 Vol.18 No.1

This study investigated the phenomena of membrane fouling by NOM and the effect of the fouling on removal of micro-pollutants. NOM has a great effect on decline of permeate flux. Permeate flow rate was reduced by 88% in RO and 34.8% in NF for 323hr operation period. Removal rate of UV_(254), is 87.4% in RO and 78.5% in NF and removal rate of DOC is 42.7% in RO and 32.9% in NF for 2㎎/l humic acid. Removal efficiency of the micmpollutants by the RO and NF membranes fouled by humic acid was mostly lower than that by the new membrane. The concentration polarization which affects the flux and the rejection was thought to occur in the active layer of the membrane, as the membrane was getting fouled.

Comparison of Prenatally Diagnosed Fetal Congenital Cystic Adenomatoid Malformation and Bronchopulmonary Sequestration

( Ju Hyun Ryu ),( Hyun Hwa Cha ),( Suk Joo Choi ),( Soo Young Oh ),( Cheong Rae Roh ),( Jong Hwa Kim ) 대한산부인과학회 2011 Obstetrics & Gynecology Science Vol.54 No.7

This study is to investigate and compare the pregnancy outcomes and prognostic factors of congenital cystic adenomatoid malformation (CCAM) and bronchopulmonary sequestration (BPS). Methods From May 2005 to September 2010, fifty-five medical records of fetuses with prenatally diagnosed CCAM (42 cases) and BPS (13 cases) were reviewed retrospectively in Samsung Medical Center (SMC). We compared the demographic characteristics, sonographic findings, postnatal diagnoses and pregnancy outcomes between CCAM and BPS. The sonographic findings included the locations of lesion, changes of size, existences of mediastinal shift, associated anomalies and existences of hydrops. Postnatal diagnoses were confirmed by pathologic findings and image examinations. Results A total of fifty-five cases were prenatally diagnosed as CCAM (42 cases) and BPS (13 cases). Thirty cases were followed up in SMC. Three of the thirty cases underwent termination and one case was intrauterine fetal death. Twenty-six cases were delivered alive in SMC. The masses were found out to be disappeared by prenatal sonography in four cases (15.4%) who were antenatally diagnosed as CCAM. The sizes of the mass were decreased more than 50% in CCAM seven cases and BPS three cases. The absence of mediastinal shift ( P=0.019) was significantly correlated with the decrease of mass size. Conclusion The concordance rate between antenatal and postnatal diagnosis was 63.0%. There was a tendency of decreasing in lesion with most of the cases. Without mediastinal shift, the mass size decreased significantly. So, existence of mediastinal shift is the most important prognostic factor of CCAM and BPS.

Changes in expression of hair-related bioactive factors in sebocytes cultured from nevus sebaceous

( Hyun Wuk Cha ),( Han Jin Jung ),( Hyun Jung Lim ),( Seok Jong Lee ),( Do Won Kim ),( Weon Ju Lee ) 대한피부과학회 2011 초록집 Vol.49 No.20

Cutaneous neoplasms with overlying scalp alopecia

( Hyun Wuk Cha ),( Kyung Hea Park ),( Han Jin Jung ),( Hyun Jung Lim ),( Yong Hyun Jang ),( Seok Jong Lee ),( Do Won Kim ),( Weon Ju Lee ) 대한피부과학회 2011 초록집 Vol.49 No.20

Cartilage tissue formation from dedifferentiated chondrocytes by codelivery of BMP-2 and SOX-9 genes encoding bicistronic vector.

Cha, Byung-Hyun,Kim, Jae-Hwan,Kang, Sun-Woong,Do, Hyun-Jin,Jang, Ju-Woong,Choi, Yon Rak,Park, Hansoo,Kim, Byung-Soo,Lee, Soo-Hong Pergamon Press ; Elsevier Science Ltd ; Elsevier S 2013 Cell transplantation Vol.22 No.9

<P>Articular cartilage, when damaged by degenerative disease or trauma, has limited ability for self-repair. Recently, many trials have demonstrated that gene therapy combined with tissue engineering techniques would be a promising approach for cartilage regeneration. Bone morphogenetic protein 2 (BMP-2) is an important signal for upregulation of osteogenesis and chondrogenesis of stem cells. Sex-determining region Y box gene 9 (SOX-9) has also been reported as one of the key transcription factors for chondrogenesis. We hypothesized that codelivery of BMP-2 and SOX-9 genes would result in improved efficiency of recovery of normal chondrogenic properties in dedifferentiated chondrocytes. To this aim, we constructed a bicistronic vector encoding the BMP-2 and SOX-9 genes linked to the 'self-cleaving' 2A peptide sequence. After gene delivery to dedifferentiated chondrocytes using a microporator transfection system, we confirmed over 65% delivery efficiency of the BMP-2 and SOX-9 genes. According to RT-PCR analysis and Alcian blue staining, simultaneous delivery of BMP-2/SOX-9 resulted in significantly increased expression of chondrogenesis-related markers (type II collagen and aggrecan) and GAG matrix formation compared with individual delivery of the BMP-2 or SOX-9 gene. Six weeks after in vivo transplantation, BMP-2/SOX-9 genes also showed a significant increase in cartilage formation compared with the BMP-2 or SOX-9 gene. These results demonstrate that codelivery of two chondrogenic lineage-determining genes can enhance normal chondrogenic properties of dedifferentiated chondrocytes followed by improved cartilage formation.</P>

Effectiveness and Safety of Adjunctive Pharmacopuncture to Acupuncture Treatment for Rotator Cuff Diseases: a Protocol for an Assessor-Blinded, Pragmatic Randomized Controlled, Pilot Trial

Cha Hyun Ji,Han Chang-Hyun,Jeon Ju Hyun,Jeong Jeong Kyo,Kim Hong Kyoung,Yang Changsop,Kang Byoung-Kab,Kim Min Ji,Choi Young Eun,Ha In-Hyuk,Kim Young Il 사단법인약침학회 2023 Journal of Acupuncture & Meridian Studies Vol.16 No.2

Background: Shoulder pain is a common musculoskeletal disorder. Treatment can be surgical or non-surgical. Korean Medicine, including acupuncture and pharmacopuncture, is a part of conservative treatment. Pharmacopuncture, combining acupuncture with herbal medicine, has been used for musculoskeletal disorders since the 1960s, but clinical evidence on its effectiveness is lacking. Objectives: This study aims to assess the effectiveness and safety of pharmacopuncture for rotator cuff disease. Methods: A two-group, parallel, single-center, pragmatic, randomized, controlled, assessor-blinded trial will be conducted. A total of 40 patients will be recruited, starting in July 2022. All patients will be received acupuncture treatment, and pharmacopuncture will be applied to intervention group additionally. After eight treatments are delivered over four weeks, follow-up assessments will be performed. Results: Assessments will evaluate the effectiveness and safety of these treatments at baseline and at weeks 2 (2 W), 4 (4 W), and 8 (8 W). The primary outcome will be a visual analog scale (VAS) evaluation of shoulder pain levels. Assessments will include shoulder pain and disability index (SPADI), shoulder range of motion (ROM), EuroQol 5-Dimension 5-Level (EQ-5D-5L), patient global impression of change (PGIC), ‘no worse than mild pain’, and drug consumption rates. Conclusion: This study may offer a rationale for a future full-scale trial on the effectiveness and safety of pharmacopuncture treatment for rotator cuff disease and provide data on non-surgical treatment for the disease.

The diagnosis of an imperforate anus in female fetuses

( Hyun Mi Kim ),( Hyun-hwa Cha ),( Jong In Kim ),( Won Joon Seong ),( Sook-hyun Park ),( Mi Ju Kim ) 영남대학교 의과대학 2021 Yeungnam University Journal of Medicine Vol.38 No.3

Imperforate anus is an anomaly caused by a defect in the development of the hindgut during early pregnancy. It is a relatively common congenital malformation and is more common in males. Although there are cases of a solitary imperforate anus, the condition is more commonly found as a part of a wider spectrum of other congenital anomalies. Although urgent reconstructive anorectal surgery is not necessary, immediate evaluation is important and urgent decompressive surgery may be required. Moreover, as there are often other anomalies that can affect management, prenatal diagnosis can help in optimizing perinatal care and prepare parents through prenatal counseling. In the past, imperforate anus was diagnosed by prenatal ultrasonography based on indirect signs such as bowel dilatation or intraluminal calcified meconium. Currently, it is diagnosed by directly checking the perineum with prenatal ultrasonography. Despite advances in ultrasound technology, accurate prenatal diagnosis is impossible in most cases and imperforate anus is detected after birth. Here, we present two cases of imperforate anus in female fetuses that were not diagnosed prenatally.

Histomorphometric evaluation of the bone surrounding orthodontic miniscrews according to their adjacent root proximity

Hyun-Ju Oh,Jung-Yul Cha,Hyung-Seog Yu,Chung-Ju Hwang 대한치과교정학회 2018 대한치과교정학회지 Vol.48 No.5

Objective: This study was conducted to perform histomorphometric evaluations of the bone surrounding orthodontic miniscrews according to their proximity to the adjacent tooth roots in the posterior mandible of beagle dogs. Methods: Four male beagle dogs were used for this study. Six orthodontic miniscrews were placed in the interradicular spaces in the posterior mandible of each dog (n = 24). The implanted miniscrews were classified into no loading, immediate loading, and delayed loading groups according to the loading time. At 6 weeks after screw placement, the animals were sacrificed, and tissue blocks including the miniscrews were harvested for histological examinations. After analysis of the histological sections, the miniscrews were categorized into three additional groups according to the root proximity: high root proximity, low root proximity, and safe distance groups. Differences in the bone–implant contact (BIC, %) among the root proximity groups and loading time groups were determined using statistical analyses. Results: No BIC was observed within the bundle bone invaded by the miniscrew threads. Narrowing of the periodontal ligament space was observed in cases where the miniscrew threads touched the bundle bone. BIC (%) was significantly lower in the high root proximity group than in the low root proximity and safe distance groups. However, BIC (%) showed no significant differences among the loading time groups. Conclusions: Regardless of the loading time, the stability of an orthodontic miniscrew is decreased if it is in contact with the bundle bone as well as the adjacent tooth root.

Association between gestational age at delivery and lymphocyte-monocyte ratio in the routine second trimester complete blood cell count

( Hyun-hwa Cha ),( Jong Mi Kim ),( Hyun Mi Kim ),( Mi Ju Kim ),( Gun Oh Chong ),( Won Joon Seong ) 영남대학교 의과대학 2021 Yeungnam University Journal of Medicine Vol.38 No.1

Background: We aimed to determine whether routine second trimester complete blood cell (CBC) count parameters, including neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), and platelet-lymphocyte ratio (PLR), could predict obstetric outcomes. Methods: We included singleton pregnancies for which the 50-g oral glucose tolerance test and CBC were routinely performed between 24 and 28 weeks of gestation in our outpatient clinic from January 2015 to December 2017. The subjects were divided into three groups according to their pregnancy outcomes as follows: group 1, spontaneous preterm births, including preterm labor and preterm premature rupture of membranes; group 2, indicated preterm birth due to maternal, fetal, or placental causes (hypertensive disorder, fetal growth restriction, or placental abruption); and group 3, term deliveries, regardless of the indication of delivery. We compared the CBC parameters using a bivariate correlation test. Results: The study included 356 pregnancies. Twenty-eight subjects were in group 1, 20 in group 2, and 308 in group 3. There were no significant differences between the three groups in neutrophil, monocyte, lymphocyte, and platelet counts. Although there was no significant difference in NLR, LMR, and PLR between the three groups, LMR showed a negative correlation with gestational age at delivery (r=-0.126, p=0.016). Conclusion: We found that a higher LMR in the second trimester was associated with decreased gestational age at delivery. CBC parameters in the second trimester of pregnancy could be used to predict adverse obstetric outcomes.