• Carbon letters
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• 제13권1호
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• pp.1-16
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• 2012

The near explosion of attention given to graphene has attracted many to its research field. As new studies and findings about graphene synthesis, properties, electronic quality control, and possible applications simultaneous burgeon in the scientific community, it is quite hard to grasp the breadth of graphene history. At this stage, graphene's many fascinating qualities have been amply reported and its potential for various electronic applications are increasing, pulling in ever more newcomers to the field of graphene. Thus it has become important as a community to have an equal understanding of how this material was discovered, why it is stirring up the scientific community and what sort of progress has been made and for what purposes. Since the first discovery, the hype has expediently led to near accomplishment of industrial-sized production of graphene. This review covers the progress and development of synthesis and transfer techniques with an emphasis on the most recent technique of chemical vapor deposition, and explores the potential applications of graphene that are made possible with the improved synthesis and transfer.

• 임상이비인후과
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• 제29권2호
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• pp.190-197
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• 2018

Background and Objectives : Positional OSAS is characterized by an apnea-hypopnea index (AHI) score >5, which, while sleeping in the supine position, is double that in non-supine position. This study was performed to compare the clinical characteristics of positional OSAS and non-positional OSAS patients, and the effects of the modified jaw thrust maneuver during drug-induced sleep endoscopy (DISE) between positional OSAS and non-positional OSAS patients. Materials and Methods : 68 positional OSAS patients and 19 non-positional OSAS patients were included. They all underwent full-night polysomnography and DISE. The modified jaw thrust maneuver was introduced during DISE. Airway structural changes induced by the modified jaw thrust maneuver were evaluated and documented. Results : There were no statistically significant differences in Friedman stage or tonsil grade, body mass index, Epworth sleepiness scale (ESS) score, blood pressure, AHI, or obstructive pattern between the positional and non-positional OSAS patients. However, mean arterial oxygen saturation (SaO2), lowest SaO2, and total arousal index values were more severe in the non-positional OSAS patients. After introduction of the modified jaw thrust maneuver, retrolingual level obstruction showed a tendency toward a higher rate of airway opening in positional OSAS patients than in non-positional OSAS patients. Conclusions : The effects of a mandibular advancement device (MAD) can be estimated by carrying out a modified jaw thrust maneuver during DISE. The tendency toward a higher rate of airway opening in positional OSAS patients than non-positional OSAS patients in retrolingual level obstruction after jaw thrust maneuver introduced during DISE may be clinically important for MAD.

• Journal of Trauma and Injury
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• 제37권1호
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• pp.48-59
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• 2024

Purpose: Research on rib fracture management has exponentially increased. Predicting fracture patterns based on the mechanism of injury (MOI) and other possible correlations may improve resource allocation and injury prevention strategies. The Chest Injury International Database (CIID) is the largest prospective repository of the operative and nonoperative management of patients with severe chest wall trauma. The purpose of this study was to determine whether the MOI is associated with the resulting rib fracture patterns. We hypothesized that specific MOIs would be associated with distinct rib fracture patterns. Methods: The CIID was queried to analyze fracture patterns based on the MOI. Patients were stratified by MOI: falls, motor vehicle collisions (MVCs), motorcycle collisions (MCCs), automobile-pedestrian collisions, and bicycle collisions. Fracture locations, associated injuries, and patient-specific variables were recorded. Heat maps were created to display the fracture incidence by rib location. Results: The study cohort consisted of 1,121 patients with a median RibScore of 2 (range, 0-3) and 9,353 fractures. The average age was 57±20 years, and 64% of patients were male. By MOI, the number of patients and fractures were as follows: falls (474 patients, 3,360 fractures), MVCs (353 patients, 3,268 fractures), MCCs (165 patients, 1,505 fractures), automobile-pedestrian collisions (70 patients, 713 fractures), and bicycle collisions (59 patients, 507 fractures). The most commonly injured rib was the sixth rib, and the most common fracture location was lateral. Statistically significant differences in the location and patterns of fractures were identified comparing each MOI, except for MCCs versus bicycle collisions. Conclusions: Different mechanisms of injury result in distinct rib fracture patterns. These different patterns should be considered in the workup and management of patients with thoracic injuries. Given these significant differences, future studies should account for both fracture location and the MOI to better define what populations benefit from surgical versus nonoperative management.

• 대한치과보철학회지
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• 제37권3호
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• pp.375-382
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• 1999

The purpose of this article is to present the clinical and laboratory procedures for single tooth restoration using 'Combination Implant Crown'. It is cemented on implant abutment and that abutment is screw-retained over implant body. This type of implant restorations has the advantages of cement-retained restoration while being antirotational and retrievable. And, more esthetic and functional result can be achieved by minimizing the size of access hole. The results were as follows : 1. Preparation of abutment below the cuff line should be avoided 2. Axial reduction of implant abutment should not be excessive because it may weaken the abutment 3. More esthetical and functional occlusal surface was achieved with a minimal access hole which is slightly larger than the diameter of hex driver to enable future total retrievability. 4. Combination Implant Crown has the advantages of both the cement-retained and screw-retained type implant restoration. 5. Cementation between implant crown and abutment reduces screw loosening through even force distribution

• Journal of Korean Neurosurgical Society
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• 제38권5호
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• pp.350-354
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• 2005

Objective : The aim of this study is to assess the immediate and long-term efficacy of percutaneous vertebroplasty for treating painful vertebral osteoporotic fractures. Methods : A retrospective review of 149patients who had undergone 167 vertebroplasty procedures for osteoporotic fractures was performed. Clinical, radiologic, and procedural datas were analyzed as parameters of prognostic significance, including age, sex, bone marrow density score, symptom duration, bone cement filling grade, number of fractured vertebrae, compression grade of vertebrae, leakage of bone cement, volume of bone cement injected and complications. Results : In 158 of the 167 procedures assessed, immediate pain relief was obtained [94.6%]. The extent of collapse of the vertebral body was assessed as a parameter for prognostic significance [p=0.015]. Three months postoperatively, no improvement of the pain was observed in four of the 167 procedures that had undergone the vertebroplasty [2%]. At long-term follow-up, the improvement of pain was not correlated with the compression grade of vertebrae [p=0.420]. Conclusion : The immediate outcome of vertebroplasty are less effective in vertebrae more collapsed.

• Journal of Yeungnam Medical Science
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• 제28권2호
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• pp.165-172
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• 2011

Gastric glomus tumor is a rare mesenchymal tumor that originates from modified smooth muscle cells of the glomus body. Glomus tumors are commonly observed in peripheral soft tissue, such as dennis or subungal region, but rarely in the gastrointestinal tract. A 39-year-old woman was admitted due to epigastric soreness. Upper gastrointestinal endoscopy revealed a subepithelial mass measuring 3.5 cm with central ulceration at the lesser curvature-posterior wall of the antrum. Characteristically, contrast enhanced abdominal computed tomography scan demonstrated high enhancement of the submucosal mass up to the same level of the abdominal aorta in the arterial phase; this enhancement persisted to delayed phase. Due to the risk of bleeding and malignancy, wedge resection of the submucosal tumor was performed. Histologic findings were compatible with a glomus tumor.

• Journal of Gastric Cancer
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• 제16권3호
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• pp.191-194
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• 2016

Hypercalcemia of malignancy due to metastatic gastric adenocarcinoma is extremely rare; in fact, to the best of our knowledge, only three case reports of hypercalcemia associated with metastatic gastric adenocarcinoma have been published in the literature to date. Herein, we report a rare case involving a 61-year-old African-American female who had hypercalcemia at initial presentation and who was later diagnosed with poorly differentiated gastric adenocarcinoma with extensive liver metastases, without bone involvement. She was found to have elevated parathyroid hormone-related peptide and normal parathyroid hormone levels. Despite aggressive treatment, she died within a few months of diagnosis.

• Journal of Korean Neurosurgical Society
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• 제30권7호
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• pp.947-950
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• 2001

Cavernous angiomas are being increasingly well recognized throughout the central nervous system due to the widespread use of magnetic resonance imaging(MRI). However, these malformations are uncommon in the spinal column and rarely occur in the spinal cord. Here, we report a case of a cervical cord intramedullary cavernous angioma in a 49-year-old man. The patient had complained of left upper extremity paresthesia and weakness in the left hand for 5 days prior to admission. A neurological examination showed a left C-6 dermatome paresthesia and a weakness in the left hand grasping power. A MRI demonstrated a mixed signal intensity core at the C-5 level and a surrounding edema on the T-2 weighted image. Conservatively, a laminectomy was performed and slightly hard and well demarcated intramedullary mass was removed. A histological examination confirmed the diagnosis of a cavernous angioma.

• 대한치과교정학회지
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• 제49권2호
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• pp.89-96
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• 2019

Objective: The purpose of this study was to assess the long-term stability of rapid palatal expansion (RPE) followed by full fixed edgewise appliances. Methods: This study included 67 patients treated using Haas-type RPE and non-extraction edgewise appliance therapy at a single orthodontic practice. Serial dental casts were obtained at three different time points: pretreatment ($T_1$), after expansion and fixed appliance therapy ($T_2$), and at long-term recall ($T_3$). The mean duration of the $T_1-T_2$ and $T_2-T_3$ periods was $4.8{\pm}3.5years$ and $11.0{\pm}5.4years$, respectively. The dental casts were digitized, and the computed measurements were compared with untreated reference data. Results: The majority of treatment-related increases in the maxillary and mandibular arch measurements were statistically significant (p < 0.05) and greater than expected for the untreated controls. Although many measurements decreased postretention ($T_2-T_3$), the net gains persisted for all of the measurements evaluated. Conclusions: The use of RPE therapy followed by full fixed edgewise appliances is an effective method for increasing maxillary and mandibular arch width dimensions in growing patients.

• Current Applied Physics
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• 제18권11호
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• pp.1294-1299
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• 2018

In this paper, we demonstrate the feasibility of constructing DNA nanostructures (i.e. DNA rings and double-crossover (DX) DNA lattices) with appropriate doxorubicin hydrochloride (DOX) concentration and reveal significant characteristics for specific applications, especially in the fields of biophysics, biochemistry and medicine. DOX-intercalated DNA rings and DX DNA lattices are fabricated on a given substrate using the substrateassisted growth method. For both DNA rings and DX DNA lattices, phase transitions from crystalline to amorphous, observed using atomic force microscopy (AFM) occurred above a certain concentration of DOX (at a critical concentration of DOX, $30{\mu}M$ of $[DOX]_C$) at a fixed DNA concentration. Additionally, the coverage percentage of DNA nanostructures on a given substrate is discussed in order to understand the crystal growth mechanism during the course of annealing. Lastly, we address the significance of optical absorption and photoluminescence characteristics for determining the appropriate DOX binding to DNA molecules and the energy transfer between DOX and DNA, respectively. Both measurements provide evidence of DOX doping and $[DOX]_C$ in DNA nanostructures.