• Journal of Electrochemical Science and Technology
• /
• 제6권3호
• /
• pp.106-110
• /
• 2015

This study investigates Cu(II) complexes of cyclam, propylene cross-bridged cyclam (PCB-cyclam), and propylene cross-bridged cyclam diacetate (PCB-TE2A) as homogeneous electrocatalysts for CO₂ reduction in comparison with Ni(II)-cyclam. It is found that Cu(II)-cyclam can catalyze CO₂ reduction at the potential close to its thermodynamic value (0.75 V vs. Ag/AgCl) in tris-HCl buffer (pH 8.45) on a glassy carbon electrode. Cu(II)-cyclam, however, suffers from severe demetalation due to the insufficient stability of Cu(I)-cyclam. Cu(II)-PCB-cyclam and Cu(II)-PCB-TE2A are revealed to exhibit much less demetalation behavior, but poor CO₂ reduction activities as well. The inferior electrocatalytic ability of Cu(II)-PCB-cyclam is ascribed to its redox potential that is too high for CO₂ reduction, and that of Cu(II)-PCB-TE2A to the steric hindrance preventing facile contact with CO₂ molecules. This study suggests that in addition to the redox potential and chemical stability, the stereochemical aspect has to be considered in designing efficient electrocatalysts for CO₂ reduction.

• Archives of Plastic Surgery
• /
• 제37권3호
• /
• pp.277-280
• /
• 2010

Purpose: The resection of locally advanced or recurred breast cancers frequently result in large chest wall defects and it leads to a great challenges to cover. Generally simple skin grafts are not a practical option for patients because of their poor cosmetic appearance and prognosis. The latissimus dorsi and rectus abdominis musculocutaneous flap have traditionally been recommended for closure of these large defects. Though the cosmetic result of reconstruction using these flaps is often excellent, but has significant drawbacks. Therefore, we thought that chest wall reconstruction using the external oblique musculocutaneous flap can be an alternative method for extensive chest wall defect related to large, locally advanced breast carcinoma. Methods & Results: We present a case of a 50-year-old Korean female, refered to our department with a left breast tumor for 10 months. CT demonstrate a large tumor on the left anterior chest wall and multiple nodules of varying size in the cervical areas and liver. FDG-PET showed areas of hot uptake throughout the left chest wall, mediastinum and liver. Biopsy was consistent with invasive ductal carcinoma (Grade III). The initial tumor was considered inoperable, so a series of chemotherapy was initiated. Though the size of the breast mass was slightly decreased, the patient continued to suffer from purulent discharge, unpleasant odor and contact bleeding of the mass, the salvage mastectomy was performed. Conclusion: We could reconstruct $23{\times}16\;cm$ sized large chest wall defect, resulting from the resection of a locally advanced breast carcinoma, using an external oblique musculocutaneous flap successfully. Immediate postoperatively checked flap was healthy. Overall result was good without any significant complications and discharged 3 weeks after operation.

• 한국보건간호학회지
• /
• 제14권1호
• /
• pp.26-40
• /
• 2000

This study was conducted to find out residential environment, mood states, ADL(Activity Daily Living) and nursing need of the elderly who live alone. The questionnaire survey was conducted on 154 single household elderly over 65years who live n D-city, Kangwon Province. The data were collected between September 1. 1999 and October 17, 1999 and analyzed by means of SPSS package. The results were as follows; 1. The percentage of the subjects who owned their house was no were than $13\%$., which showed that they still belonged to the economically vulnerable class. As for their residential environment, the average indoor temperature and humidity level were $16.45^{\circ}C\;and\;44.62\%$ respectively during the daytime between September and October, which proved to range within the standard scope. The average indoor illumination level was, however, 43.61 Lux, which showed that their illumination environment was very poor. 2. The average score of their mood states was 3.31. which turned out to be rather low. 3. The mean score of ADL was 1.69, which showed that they didn't have any serious inconveniences in their ordinary lives. 4. The mean score of their nursing need was 275, which proved to be close to the normal level. 5. The higher the room humidity was, the higher their nursing need increased. The higher the degree of illumination level was, the lower the degree of their nursing need was and the higher the level of ADL was. 6. The major factors influencing their moon status were the frequency of their contact with children and room humidity. These two factors could account for $22\%$ of the total mood status. These results suggest that the residential environment should be necessarily considered in the psychological nursing intervention for the elderly who live alone and they should be urgently supported in terms of health policy so that they can maintain the optimum level of illumination during the daytime.

• 한국안전학회지
• /
• 제32권6호
• /
• pp.22-28
• /
• 2017

According to the National Fire Data System (NFDS), more than 5,000 vehicle fires have occurred every year for the last 10 years. Vehicle fires are primarily caused by mechanical (breaking system and engine), electrical (wiring and battery), and chemical (oil and fuel gas leakage) problems. The electrical factor has increased with the installation of driver convenience equipment. For example, today, the black box is widely used to provide video data recording of motor vehicle accidents. The black box consists of a front camera, rear camera, and wires. The black box wires are directly connected to the junction box or fuse box from the start battery that operates to provide normal on power supplying for engine stop. It is extremely dangerous when the wires short circuit due to insulation aging, mechanical and electrical stress, etc. In this study, the black box wiring fire risk have been analyzed and investigated when the steady state and abnormal operations, and under the following conditions: wiring arrangements with a high temperature condition, insulation aging, poor contact, and short circuits. The results showed that black box wiring short circuits had a higher fire risk than the other fire hazard elements. To prevent fire hazards caused by black box wiring, the black boxes must be installed by qualified service personnel. Do not modify the wiring, remove the fuse and secure the wiring using cable ties or insulation tape.

• 조명전기설비학회논문지
• /
• 제23권10호
• /
• pp.100-106
• /
• 2009

본 논문에서는 전기설비의 전기적 접속부 또는 전기배선 등에서 발생하는 이상발열을 감지하는 방법에 대해 알아보고, 분전함에서의 발열상태를 실시간으로 모니터링하는 전력설비 진단시스템에 사용되고 있는 광온도센서에 대하여 동작특성을 실험, 분석하였다. 광온도센서의 동작특성 실험을 위한 열원으로는 Black Body와 Hot Plate를 사용하였으며 각각에서의 열원의 온도변화에 따른 광온도센서 출력전압값을 측정, 분석하였다. 그리고 분전함내 차단기 단자에서의 체결불량으로 인한 이상발열 감지 실험을 기존의 발열 감지방법인 열전대와 적외선 열화상장치를 이용하여 실시하였고, 광온도센서를 이용해 실시하여 결과를 비교 분석하였다. 실험결과, 광온도센서의 이상발열 감지능력이 유사함을 확인할 수 있었다. 이러한 분석 결과는 향후 RFID형 광온도센서를 이용한 전력설비 진단시스템의 현장 적용에 있어 기본 자료가 될 것으로 기대된다.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
• /
• pp.229-232
• /
• 2000

본 연구에서는 균주의 배양과 동시에 생산물을 회수할 수 있는 동시추출공정을 건조질량의 $15{\sim}75%$의 탄화수소를 생산한다고 알려진 B. braunii 배양에 적용하고자 한다. 일반적인 two-phase 동시추출공정의 적용시 B. braunii의 경우 생산된 탄화수소가 균주 외벽의 matrix에 강하게 부착되어 있기 때문에, two phase 추출공정 적용시 bubble column내에서 단지 폭기에 의한 교반만으로는 충분한 탄화수소의 회수율을 얻을 수가 없었다. 본 연구에서는 배양액과 유기용매층의 접촉기회를 증대시킨 two-stage 동시추출 공정을 개발하여 기존의 two-phase 동시추출 공정보다 2배 이상 높은 56.2%의 탄화수소 회수율을 얻을 수가 있었다.

• 대한치과보철학회지
• /
• 제37권5호
• /
• pp.607-619
• /
• 1999

Cortical support is an important factor, as the engagement of the fixture in strong compact bone offers an increased load-carrying capacity and initial stability. Because of the poor bone quality in the posterior mandible and other anatomic considerations, it has been suggested that implant fixtures be placed in these locations with apical engagement of the lingual cortical plate for so-called bicortication. The purpose of this investigation was to determine the effect of cortical engagements and in addition polyoxymethylene(POM) intramobile connector(IMC) of IMZ implant on implant load transfer in edentulous posterior segment of mandible, using three-dimensional (3D) finite element analysis models composed of cortical and trabecular bone involving single implant. Variables such as (1) the crestal peri-implant defect, (2) the apical engagement of lingual cortical plate, (3) the occlusal contact position (a vertical load at central fossa or buccal cusp tip), and (4) POM IMC were investigated. Stress patterns were compared and interfacial stresses along the bone-implant interface were monitored specially. Within the scope of this study, the following observations were made. 1) Offset load and angulation of fixture led to increase the local interfacial stresses. 2) Stresses were concentrated toward the cortical bones, but the crestal peri-implant defect increased the interfacial stresses in trabecular bone. 3) For the model with bicortication, it was noticed that the crestal cortical bone provided more resistance to the bending moment and the lingual cortical plate provided more support for the vertical load. But Angulation problem of the fixture from the lingual cortical engagement caused the local interfacial stress concentrations. 4) It was not clear that POM IMC had the effect on stress distribution under the present experimental conditions, especially for the cases of crestal peri-implant defect.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권5호
• /
• pp.337-342
• /
• 2012

The osseous or osteocutaneous free fibula flap has become the gold standard for most mandibular reconstructions because of its favorable osseous characteristics. However, disadvantages, such as the time-consuming reconstructive step, difficulty in performing the osteotomies to precisely recreate the shape of the missing segment of mandible and poor bone-to-bone contact play a role in making the surgeons look for alternative flaps. With the advent of computerized design software, which accurately plans complex 3-dimensional reconstructions, has become a process that is more efficient and precise. However, the ability to transfer the computerized plan into the surgical field with stereolithographic models and guides has been a significant development in advancing reconstruction in the maxillofacial regions. The ability to "pre-plan" the case, mirror and superimpose natural structures into diseased and deformed areas, as well as the ability to reproduce these plans with good surgical precision has decreased overall operative time, and has helped facilitate functional and esthetic reconstruction. We describe a complex case treated with this technique, showing the power and elegance of computer assisted maxillofacial reconstruction from the University of Michigan, Oral and Maxillofacial Surgery.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제41권5호
• /
• pp.265-269
• /
• 2015

The purpose of this study was to investigate implant-supported restoration as a technique for restoring missing teeth in patients with aplastic anemia. Recurrent bleeding from wound sites leads to persistent release of iron in the tissue. Excessive iron in tissue is related to clinical findings, including fibrosis, poor wound healing, and high level of angiogenesis, which are possible etiological factors of reduced osseointegration. A 44-year-old female patient with aplastic anemia was treated with multiple endosseous implants throughout the mandible and in the posterior region of the maxilla. After 14 implants were placed, radiological and clinical parameters were assessed during the follow-up period. Marginal bone did not change significantly during the follow-up period. The fine trabecular bone in intimate contact and enclosing the implant fixture was sufficient for successful osseointegration. None of the 14 implants were associated with compilations during the seven-year experimental period. This study suggests that dental implant procedures are a safe and reliable treatment option for restoration of missing dentition in patients with aplastic anemia.

• Parasites, Hosts and Diseases
• /
• 제54권4호
• /
• pp.447-453
• /
• 2016

Acanthamoeba, a free-living amoeba, is widely distributed in the environment, water sources, soil, dust, and air. It can cause keratitis in contact lens wearers with poor hygiene and also fatal granulomatous amebic encephalitis (GAE) in immunocompromised hosts. The aim of this study was to gain some insights into the distribution and genotypes of the potentially pathogenic species of Acanthamoeba present in water sources in north of Iran. Total 43 Acanthamoeba species were isolated from 77 water samples taken from different water sources within the Mazandaran province in Northern Iran (Sari city and suburbs). Isolates were identified based on cyst and trophozoite morphological characteristics as well genetics. PCR fragments corresponding to the small-subunit 18S rRNA gene were sequenced for 20 of 43 positive isolates. The results revealed that 83.3% of sequenced isolates belonged to the T4 genotype and the rest belonged to the T2 genotype. Our results indicated that Acanthamoeba is widely distributed in Sari city. As the incidence in Iran of amoebic keratitis has increased in recent years, the exact estimation of the prevalence of this amoeba and its predominant genotype may play a crucial role in prevention of the disease. Sari city has several rivers, seashores, and natural recreational amenities, which attract visitors during the year. This is the first report of Acanthamoeba genotypes from water sources in Sari city, Mazandaran province of Iran, and the results suggest that more attention is needed to protect the visiting population and immunocompromised individuals.