• 제목/요약/키워드: R-mark

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방사성 동위원소를 이용한 영일만 해역표사의 조사 (The Determination of the Sand Drift Movement Using Radioactive Tracer at Young Il Bay)

  • 양경린
    • 한국해양학회지
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    • 제4권1호
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    • pp.9-16
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    • 1969
  • 금번 국내최대의 포항종합제철공장의 건립에 즈으하여 국내최대의 새로운 항만이 영일만내에 건설되고 있다. 항만의 건설의 외곽시설인 방파제 방사제 및 항입구의 배치계획에 기초자료가 된느 여러 조사업무중의 하나로 당 해역의 표사의 이동에 대한 조사가 실시되었다. 항만건설해역은 형산강과 냉천 사이의 해역으로써 이들 하천으로 부터의 유사가 표사이동에 미치는 영양도 아울러 조사되었으며, 표사의 공급원, 표사의 이동방향을 알기 위하여 광범위한 해역에 걸쳐 조사가 진행되었다. 표사는 해안을 따라 어떤 폭을 갖은 해변에서 발생하는 저질의 이동현상을 말하며, 하천의 유사와 마찬가지로 유체에 의한 물질의 운반작용이지만 그 운반기구는 하천의 유사에 비하여 대단히 복잡하여서 그의 정확한 선택파악은 대단히 어려운 문제이다. 최근 이와 같은 조사에 방사성물질이 추적자로 사용되고 있으며, 종래 사용되던 간접적인 방법에 비하여 비교적 간단히 그리고 직접적으로 표사의 실태를 파악할 수 있으미 확인되고 있다. 금번 조사에서는 방사성 추적자로서 Co-60을 사용하였다.

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A TWO-YEAR STUDY OF IMPLANT RETAINED OVERDENTURES IN THE TREATMENT OF TOTALLY EDENTULOUS JAWS

  • Kwon, Ho-Beom;Kim, Eun-Ha;Lee, Seok-Hyoung
    • 대한치과보철학회지
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    • 제45권6호
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    • pp.760-768
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    • 2007
  • Statement of problem. Conventional denture treatment for totally edentulous patients is associated with a variety of functional and psychosocial problems. The placement of implants in the anterior region of the maxilla and mandible and the fabrication of an implant-retained overdenture might solve these problems. Purpose. This study compared the marginal bone loss around the implant and evaluated the implant survival rate and complications in patients treated with overdentures retained by implants for 2 years. Material and methods. Patients who had received implant-retained overdentures using a Dolder bar at Samsung Medical Center from January 1999 to June 2005 and had participated in the annual recall programs for two years were selected for this study. A total of 18 patients and 56 $Br{\aa}ne-mark\;system^{(R)}$ implants were used, and their data were reviewed. Evaluations of the survival rate, bone quality, marginal bone loss, and complications were performed. The data on the Dolder bar length and clip length were measured. The change in marginal bone loss and the correlation between the marginal bone loss and bar length, clip length, or bone quality were investigated. Results. Implants placed in this study showed a 100% survival rate. The average annual bone loss was 1.12mm in the first year and 0.27mm in the second year in the maxilla, and 0.58mm in the first year and 0.22mm in the second year in the mandible. The marginal bone loss in the maxilla showed no significant association with those in the mandible. (P>.05). There was no significant difference in marginal bone loss around implants between the first and second year. (P>.05) There was no statistically significant relationship (P>.05) between the marginal bone loss and bone quality, clip length, or Dolder bar length. The Dolder bar length showed a high correlation with the clip length. (P<.05) Various complications were noted. Conclusion. These results confirmed the favorable outcome for patients treated with implant-retained overdentures.

The Role of Minimally Invasive Plate Osteosynthesis in Rib Fixation: A Review

  • Bemelman, Michael;van Baal, Mark;Yuan, Jian Zhang;Leenen, Luke
    • Journal of Chest Surgery
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    • 제49권1호
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    • pp.1-8
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    • 2016
  • More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950's, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft $f{\ddot{u}}r$ osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has becomeavailable suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation.

Management of complex surgical wounds of the back: identifying an evidence-based approach

  • Zolper, Elizabeth G.;Saleem, Meher A.;Kim, Kevin G.;Mishu, Mark D.;Sher, Sarah R.;Attinger, Christopher E.;Fan, Kenneth L.;Evans, Karen K.
    • Archives of Plastic Surgery
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    • 제48권6호
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    • pp.599-606
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    • 2021
  • Background Postoperative dehiscence and surgical site infection after spinal surgery can carry serious morbidity. Multidisciplinary involvement of plastic surgery is essential to minimizing morbidity and achieving definitive closure. However, a standardized approach is lacking. The aim of this study was to identify effective reconstructive interventions for the basis of an evidence-based management protocol. Methods A retrospective review was performed at a single tertiary institution for 45 patients who required 53 reconstruction procedures with plastic surgery for wounds secondary to spinal surgery from 2010 to 2019. Statistical analysis was performed for demographics, comorbidities, and treatment methods. Primary outcomes were postoperative complications, including dehiscence, seroma, and infection. The secondary outcome was time to healing. Results The overall complication rate was 32%, with dehiscence occurring in 17%, seroma in 15% and infection in 11% of cases. Median follow-up was 10 months (interquartile range, 4-23). Use of antibiotic beads did not affect rate of infection occurrence after wound closure (P=0.146). Use of incisional negative pressure wound therapy (iNPWT) was significant for reduced time to healing (P=0.001). Patients treated without iNPWT healed at median of 67.5 days while the patients who received iNPWT healed in 33 days. Demographics and comorbidities between these two groups were similar. Conclusions This data provides groundwork for an evidence-based approach to soft tissue reconstruction and management of dehiscence after spinal surgery. Timely involvement of plastic surgery in high-risk patients and utilization of evidence-based interventions such as iNPWT are essential for improving outcomes in this population.

Clinical outcomes of a low-cost single-channel myoelectric-interface three-dimensional hand prosthesis

  • Ku, Inhoe;Lee, Gordon K.;Park, Chan Yong;Lee, Janghyuk;Jeong, Euicheol
    • Archives of Plastic Surgery
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    • 제46권4호
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    • pp.303-310
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    • 2019
  • Background Prosthetic hands with a myoelectric interface have recently received interest within the broader category of hand prostheses, but their high cost is a major barrier to use. Modern three-dimensional (3D) printing technology has enabled more widespread development and cost-effectiveness in the field of prostheses. The objective of the present study was to evaluate the clinical impact of a low-cost 3D-printed myoelectric-interface prosthetic hand on patients' daily life. Methods A prospective review of all upper-arm transradial amputation amputees who used 3D-printed myoelectric interface prostheses (Mark V) between January 2016 and August 2017 was conducted. The functional outcomes of prosthesis usage over a 3-month follow-up period were measured using a validated method (Orthotics Prosthetics User Survey-Upper Extremity Functional Status [OPUS-UEFS]). In addition, the correlation between the length of the amputated radius and changes in OPUS-UEFS scores was analyzed. Results Ten patients were included in the study. After use of the 3D-printed myoelectric single electromyography channel prosthesis for 3 months, the average OPUS-UEFS score significantly increased from 45.50 to 60.10. The Spearman correlation coefficient (r) of the correlation between radius length and OPUS-UEFS at the 3rd month of prosthetic use was 0.815. Conclusions This low-cost 3D-printed myoelectric-interface prosthetic hand with a single reliable myoelectrical signal shows the potential to positively impact amputees' quality of life through daily usage. The emergence of a low-cost 3D-printed myoelectric prosthesis could lead to new market trends, with such a device gaining popularity via reduced production costs and increased market demand.

Timing of Esophagectomy after Neoadjuvant Chemoradiation Therapy Affects the Incidence of Anastomotic Leaks

  • Roh, Simon;Iannettoni, Mark D.;Keech, John;Arshava, Evgeny V.;Swatek, Anthony;Zimmerman, Miriam B.;Weigel, Ronald J.;Parekh, Kalpaj R.
    • Journal of Chest Surgery
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    • 제52권1호
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    • pp.1-8
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    • 2019
  • Background: Neoadjuvant chemoradiation therapy (nCRT) has become the standard of care for esophageal cancer patients prior to esophagectomy. However, the optimal timing for surgery after completion of nCRT remains unclear. Methods: A retrospective review was performed of patients who underwent esophagectomy with cervical anastomosis for esophageal cancer at a single institution between January 2000 and June 2015. Patients were categorized into 3 cohorts: those who did not receive nCRT prior to esophagectomy (no nCRT), those who underwent esophagectomy within 35 days after nCRT (${\leq}35d$), and those who underwent esophagectomy more than 35 days after nCRT (>35d). Results: A total of 366 esophagectomies were performed during the study period, and 348 patients met the inclusion criteria. Anastomotic leaks occurred in 11.8% of all patients included in the study (41 of 348). Within each cohort, anastomotic leaks were detected in 14.7% of patients (17 of 116) in the no nCRT cohort, 7.3% (13 of 177) in the ${\leq}35d$ cohort, and 20.0% (11 of 55) in the >35d cohort (p=0.020). Significant differences in the occurrence of anastomotic leaks were observed between the no nCRT and ${\leq}35d$ cohorts (p=0.044), and between the ${\leq}35d$ and >35d cohorts (p=0.007). Conclusion: Esophagectomy with cervical anastomosis within 35 days of nCRT resulted in a lower percentage of anastomotic leaks.

TIMES: mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale. I. the first result.

  • Yun, Hyeong-Sik;Lee, Jeong-Eun;Choi, Yunhee;Evans, Neal J. II;Offner, Stella S.R.;Lee, Yong-Hee;Baek, Giseon;Choi, Minho;Kang, Hyunwoo;Lee, Seokho;Tatematsu, Ken'ichi;Heyer, Mark H.;Gaches, Brandt A.L.;Yang, Yao-Lun;Jung, Jae Hoon;Lee, Changhoon
    • 천문학회보
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    • 제44권1호
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    • pp.42.2-42.2
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    • 2019
  • Turbulence is one of the natural phenomena in molecular clouds. It affects gas density and velocity fluctuation within the molecular clouds and controls the mode and tempo of star formation. However, despite many years of study, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have fully mapped two star-forming molecular clouds, the Orion A and the Ophiuchus molecular clouds, in 3 sets of lines ($^{13}CO$ J=1-0, $C^{18}O$ J=1-0, HCN J=1-0, $HCO^+$ J=1-0, CS J=2-1, and $N_2H^+$ J=1-0) using the TRAO 14-m telescope. We apply a statistical analysis, Principal Component Analysis (PCA), which can recover an underlying turbulent-power spectrum from an observed P-P-V spectral map. We compare turbulence properties not only between the two clouds, but also between different parts within each cloud. We present the first result of our observation program.

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Determining the incidence and risk factors for short-term complications following distal biceps tendon repair

  • Goedderz, Cody;Plantz, Mark A.;Gerlach, Erik B.;Arpey, Nicholas C.;Swiatek, Peter R.;Cantrell, Colin K.;Terry, Michael A.;Tjong, Vehniah K.
    • Clinics in Shoulder and Elbow
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    • 제25권1호
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    • pp.36-41
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    • 2022
  • Background: Distal biceps rupture is a relatively uncommon injury that can significantly affect quality of life. Early complications following biceps tendon repair are not well described in the literature. This study utilizes a national surgical database to determine the incidence of and predictors for short-term complications following distal biceps tendon repair. Methods: The American College of Surgeons' National Surgical Quality Improvement Program database was used to identify patients undergoing distal biceps repair between January 1, 2011, and December 31, 2017. Patient demographic variables of sex, age, body mass index, American Society of Anesthesiologists class, functional status, and several comorbidities were collected for each patient, along with 30-day postoperative complications. Binary logistic regression was used to calculate risk ratios for these complications using patient predictor variables. Results: Early postoperative surgical complications (0.5%)-which were mostly infections (0.4%)-and medical complications (0.3%) were rare. A readmission risk factor was diabetes (risk ratio [RR], 4.238; 95% confidence interval [CI], 1.180-15.218). Non-home discharge risk factors were smoking (RR, 3.006; 95% CI, 1.123-8.044) and ≥60 years of age (RR, 4.150; 95% CI, 1.611-10.686). Maleness was protective for medical complications (RR, 0.024; 95% CI, 0.005-0.126). Surgical complication risk factors were obese class II (RR, 4.120; 95% CI, 1.123-15.120), chronic obstructive pulmonary disease (COPD; RR, 21.981; 95% CI, 3.719-129.924), and inpatient surgery (RR, 8.606; 95% CI, 2.266-32.689). Conclusions: Complication rates after distal biceps repair are low. Various patient demographics, medical comorbidities, and surgical factors were all predictive of short-term complications.

TRAO-TIMES: Investigating Turbulence and Chemistry in Two Star-forming Molecular clouds

  • Yun, Hyeong-Sik;Lee, Jeong-Eun;Choi, Yunhee;Evans, Neal J. II;Offner, Stella S.R.;Baek, Giseon;Lee, Yong-Hee;Choi, Minho;Kang, Hyunwoo;Cho, Jungyeon;Lee, Seokho;Tatematsu, Ken'ichi;Heyer, Mark H.;Gaches, Brandt A.L.;Yang, Yao-Lun
    • 천문학회보
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    • 제46권2호
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    • pp.37.2-37.2
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    • 2021
  • Turbulence produces the density and velocity fluctuations in molecular clouds, and dense regions within the density fluctuation are the birthplace of stars. Also, turbulence can produce non-thermal pressure against gravity. Thus, turbulence plays a crucial roles in controlling star formation. However, despite many years of study, the detailed relation between turbulence and star formation remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we mapped two star-forming molecular clouds, the Orion A and the ρ Ophiuchus molecular clouds, in six molecular lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We applied the Principal Component Analysis (PCA) to the observed data in two different ways. The first method is analyzing the variation of line intensities in velocity space to evaluate the velocity power spectrum of underlying turbulence. We investigated the relation between the star formation activities and properties of turbulence. The other method is analyzing the variation of the integrated intensities between the molecular lines to find the characteristic correlation between them. We found that the HCN, HCO+, and CS lines well correlate with each other in the integral shaped filament in the Orion A cloud, while the HCO+ line is anti-correlate with the HCN and CS lines in L1688 of the Ophiuchus cloud.

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TRAO KSP TIMES: Homogeneous, High-sensitivity, Multi-transition Spectral Maps toward the Orion A and Ophiuchus Cloud with a High-velocity Resolution.

  • Yun, Hyeong-Sik;Lee, Jeong-Eun;Choi, Yunhee;Evans, Neal J. II;Offner, Stella S.R.;Heyer, Mark H.;Lee, Yong-Hee;Baek, Giseon;Choi, Minho;Kang, Hyunwoo;Cho, Jungyeon;Lee, Seokho;Tatematsu, Ken'ichi;Gaches, Brandt A.L.;Yang, Yao-Lun;Chen, How-Huan;Lee, Youngung;Jung, Jae Hoon;Lee, Changhoon
    • 천문학회보
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    • 제44권2호
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    • pp.68.1-68.1
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    • 2019
  • Turbulence plays a crucial role in controlling star formation as it produces density fluctuation as well as non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite a plenty of previous studies, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we mapped the Orion A and the Ophiuchus clouds, in three sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) with a high-velocity resolution (~0.1 km/s) using the TRAO 14-m telescope. The mean Trms for the observed maps are less than 0.25 K, and all these maps show uniform Trms values throughout the observed area. These homogeneous and high signal-to-noise ratio data provide the best chance to probe the nature of turbulence in two different star-forming clouds, the Orion A and Ophiuchus clouds. We present comparisons between the line intensities of different molecular tracers as well as the results of a Principal Component Analysis (PCA).

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