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A thick AlN epilayer is grown directly on a c-plane sapphire substrate by using the hydride vapor phase epitaxy (HVPE) method with a small quantity of Al. The new type (RF + hot-wall) flow HVPE reactor used in the AlN epilayer growth is custommade. The growth temperatures of the source and the growth zones are set at 950 °C and 1145 °C, respectively. The characteristics of the AlN layer grown on a sapphire substrate are investigated by using energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy. The value of the full width at half maximum (FWHM) for the (002) peak from the AlN layer on the sapphire substrate is observed at 790 arcsec. From the small value of the FWHM, the AlN layer seems to be a well-arranged plane with a uniform (002) growth direction on a sapphire substrate.

Extending our previous theoretical framework, we study the heat capacity of a canonical ensemble, including the Zeeman effect, under an incident magnetic field at a specific angle with respect to the axis of the quantum-dot superlattices (QDSL’s) and confined by an isotropic parabolic potential for GaAs, InAs, and InSb, respectively. Furthermore, we numerically obtain the dependences of the heat capacity on the angle between the incident magnetic field’s direction and the superlattice axis for an isotropic, confining, parabolic potential as functions of the temperature, the effective g-factor value, and the confinement frequency in the QDSL’s of GaAs, InSb, and InAs, respectively. Particularly, the dependence of the heat capacity on the angle of the incident magnetic field is discussed in detail.

Amiodarone is an antiarrhythmic drug known to have adverse effects on multiple organs. Most studies have reported the side effects of the drug, which may result from rapid administrations or from long-term, high dosage administrations. However, toxicity issues have also been reported from patients administered with low doses of the drug for a long period of time. Here we report a case of an 82-year-old female who had shown symptoms and signs of pulmonary, hepatic, and neurotoxicity after taking amiodarone for 14 months in order to treat her atrial fibrillation without regular outpatient follow-up. We highlight the importance of the recommended evaluations, including lung, liver, and thyroid functions, as well as the neurological examinations in patients treated with amiodarone for a long period of time during regular follow-up.

We investigate the heat capacity using the previous theoretical framework for the electronic system in the quantum-dot superlattices (QDSL’s), including the Zeeman effect of GaAs, InAs, and InSb, respectively, by using an isotropic parabolic potential under a magnetic field on the basis of canonical ensemble statistics. We numerically study the dependences of the heat capacity on the confinement frequency of the isotropic parabolic potential and the electronic density as functions of the temperature and the magnetic field strength in the QDSL’s of GaAs, InSb, and InAs, respectively. Furthermore, we numerically obtain the dependences of the heat capacity on the effective g-factor value in the QDSL’s of GaAs, InSb, and InAs, respectively, as functions of the temperature and the magnetic field strength.

The angular dependence of the optically detected magnetophonon resonance (ODMPR) for the frequency-dependent magnetoconductivity in a Ge-based (nonpolar) semiconductor superlattice under a tilted magnetic field is investigated. The frequency-dependent magnetoconductivity, including the miniband width, the periodic potential, the photon frequency, and the tilt angle of a magnetic field tilted relative to the superlattice axis, is calculated using the nonpolar LO phonon modes as a function of the magnetic field strengths. In particular, the angular dependence of the ODMPR lineshape, such as the splitting and the shift of the ODMPR peaks for the photon frequency, is discussed. Furthermore, the angular dependences for the appearance of the plateau region between two neighboring ODMPR peaks and the change in the ODMPR amplitude as a function of the tilt angle of the tilted magnetic field for various miniband widths and photon frequencies are discussed in detail.

Congenital anomalies of the coronary artery are associated with various symptoms including syncope, myocardial ischemia, and sudden cardiac death. The abnormality depends on the adjacent structure and pathway of the coronary artery. Most patients with an anomalous left coronary artery that arises from a right coronary sinus of the valsalva have no symptoms and are usually diagnosed at autopsy. Therefore, their first symptom might present as sudden death, particularly when the left coronary arterial course is between the aorta and the pulmonary trunk. Symptomatic patients could be diagnosed early with an anomalous coronary artery, and the risk of fatal events could be decreased by surgical correction. Here, we report the case of 62-year-old male who experienced a first episode of syncope with an anomalous left coronary artery arising from the right sinus of the valsalva with a separate orifice from the right coronary artery. He is alive and in good health receiving medical treatment, and has had no medical events for over 2 years. (Korean J Med 2014;87:722-727)

Focal osteoporotic bone marrow defect (FOBMD) is a radiolucent area corresponding to the presence of hematopoietic tissue rarely found in the jaws. FOBMD is most commonly located in the mandibular edentulous posterior area of a middle-aged female. From November 2011 to November 2012, we experienced three cases involving removal of implants that had accidentally fallen into the FOBMD area. All patients happened to be female, with a mean age of 54 years (range: 51-60 years). One case involved hypoesthesia of the lower lip and chin, while two cases healed without any complication. Displacement of an implant into the FOBMD area is an unusual event, which occurs rarely during placement of a dental fixture. The purpose of this study was to report on three cases of FOBMD and to provide a review of related literature.

J Korean Assoc Oral Maxillofac Surg 2011;37:530-4) This paper reports two cases of schwannomas arising from the oral cavity. One is an intraoral ancient schwannoma located at the left cheek, which evolved over a period of 13 years. The tumor was a well-demarcated buccal mass, which was located in the left lower first premolar area, with an obliterated the buccal vestibule, leaving the overlying mucosa intact. The second case was a central intraosseous schwannoma located from the left lower 1st molar periapical area to the left 3rd molar periapical area. Pathologically, the first mass was composed of the spindle shaped tumor cells with wavy nuclei beneath the fibroconnective tissue of the gingiva but second case mass was not. Occasional nuclear pleomorphism was observed but mitosis or necrosis was absent. There were Antoni A and B areas along with strong, diffuse staining with the S-100 protein. Ancient schwannomas were diagnosed. Schwannoma is a slow-growing benign tumor, and an ancient schwannoma that shows cellular atypism is a variant of a schwannoma caused by purely degenerative changes. To date, only limited cases of ancient schwannomas in the oral cavity have been reported.

(J. Kor. Oral Maxillofac. Surg. 2010;36:53-56) Ⅰ. 서론 다형선종유래암종(carcinoma ex pleomorphic adenoma)은다형선종에서1-20%의발병률로변환되고빈번하게재발된다고보고되고있다. 다형선종유래암종의발병은다형선종의장기간지속, 종양의재발, 방사선치료, 가령, 그리고종양의크기와관련이있다고한다. 특히, 이질환의발병은다형선종의기간과상호관련이있으며, 악성으로발달할위험성은5년이하의다형선종에서오직1.5%이고15년이상의증례에서는9.5%로증가하였다고한다 1 . 그리고,불완전한절제가이질환의재발과관련이있다고한다 2,3 .비록다형선종유래암종에대한치료가확립되진않았지만, 광범위절제, 경부청소술, 술후방사선치료, 화학요법과함께양호하게치료되고있다고알려져있다.이에저자들은34세남자환자와81세여자환자의이하선에발생한다형선종유래암종을치험하였기에문헌고찰과함께보고하고자한다.Ⅱ. 증례보고 1. 증례134세남자환자가우측유양돌기부위의종물을주소로개인병원으로부터2006년3월본원으로의뢰되었다. 병력상우측유양돌기주변의종물이5년전부터발생하였고1년전부터크기가증가하였다고환자가진술하였다. 초진시이학적검사상우측유양돌기하방에서4 cm 크기의무통성종물이촉지되었고경결감이나파동성은없었다. 비정상적인경부임파절은촉지되지않았고연하시약간의불편감을호소하였다. 타액분비도정상이었으며안면신경마비나개구제한은관찰되지않았다. 환자의과거력상특이할만한병력이나가족력은없었다.파노라마방사선사진에서는비정상적인소견이없었고전산화단층촬영결과교근과하악골상행지후연에서유양돌기전방에이르는경계가명확한종물이관찰되었고이하선의천엽에국한된양상이었다. 자기공명영상(T2weighted image)에서고강도신호를보이는경계가명확한 김현민405-760, 인천시남동구구월동1198 가천의과대학교길병원구강악안면외과Hyeon-Min KimDepartment of Oral and Maxillofacial Surgery, Gil Hospital, Gachon University 1198, Guwol-dong Namdong-gu Incheon 405-760, KoreaTel: +82-32-460-3373, 3372 Fax: +82-32-460-3101E-mail: jumincw@hanmail.net

Optically Detected Spin-Magnetophonon Resonances in Semiconductor Superlattices Sang Chil Lee Research Institute for Basic Science and Department of Physics, Cheju National University, Jeju 690-756 (Received 28 September 2007) The in uence of the e ective g-factor from optically detected spin-magnetophonon resonance (ODSMPR) phenomena is investigated, including the Zeeman spin Hamiltonian term, in a shortperiod InAs-based polar semiconductor superlattice in magnetic elds. The conditions for the appearance of the ODSMPR line shape for various miniband widths as functions of the magnetic eld strength and the incident photon frequency applied to the short-period InAs-based polar semiconductor superlattice are obtained. We also suggest the possibility of nding the e ective g-factor value from the spin-magnetophonon resonance (SMPR) conditions. PACS numbers: 72.20.-i, 73.20.Dx, 73.50.-h, 72.20.Dp

Background and Objectives：The effects of estrogen in the myocardium of aged ovariectomized rats, relating to the estrogen replacement onset time following an ovariectomy, and the replacement duration have not yet been established. The object of this study was to investigate the effects of estrogen replacement in the myocardium of aged ovariectomized rats. Materials and Methods：52 Female Sprague Dawley rats, about 3 months old, were subjected to sham surgery only (Group 1；control, n＝9； a bilateral ovariectomy (OVX and maintained untreated for a period of 12 weeks following surgery (Group 2；OVX only, n＝16； estrogen conjugate 25 μg/kg daily for 4weeks from the 8th post ovariectomy week (Group 3；OVX＋ estrogen replacement therapy：ERT 4weeks, n＝10； estrogen conjugate 25 μg/kg daily p.o for 12weeks directly post ovariectomy (Group 4；OVX＋ERT 12weeks, n＝17. We measured the left ventricular wall thickness (LVWT, the number of cardiomyocytes and interstitial fibrosis, edema, using light and electron microscopy. Results：The LVWT in group 4 was 2.25 mm, which was significantly decreased compared to groups 2 and 3, which were 2.45 mm (p＝0.014 and 2.46 mm (p＝0.008, respectively. The LVWT in group 4 was not significantly different to that of group 1. Interstitial edema was significantly decreased in group 4 (41.2% compared to that of group 3 (62.0%(p＝0.019. The electron microscopic findings showed a decrease of crystae and a loss of matrix, resulting in a whitish discoloration of the mitochondria in groups 2 and 3. A similar finding was not observed in groups 1 and 4. Conclusion：These results suggest that early administration and maintenance of estrogen following a bilateral ovariectomy could prevent the myocardial changes caused by estrogen deficiency. (Korean Circulation J 2002;32(11 :1004-1011

Essential thrombocythemia, a subcategory of chronic myeloproliferative disorder, is characterized by absolute thrombocytosis due to excessive clonal proliferation of platelets, hyperaggregability of platelets and increased incidence of thrombosis and hemorrhage. Essential thrombocythemia may cause frequent vascular thrombosis, but it can be a rare cause of acute ischemic heart diseases such as acute myocardial infarction without atherosclerosis, unstable angina and angina pectoris. We report a case of essential thrombocythemia complicated by acute myocardial infarction. A patient with a previous history of vascular thrombotic complications(such as transient ischemic attack and deep vein thrombosis) was managed with 2.8 million units of intravenous urokinase, antiplatelet agent, ACEI, antianginal medications and hydroxyurea. There were clinically remarkable improvements and no further episodes of thrombotic ischemic vascular complications, including acute myocardial infarction.

ObjectivesWe undertook this study to determine whether human atrial fibrillation (AF) relates to steeply sloped action potential duration restitution (APDR) kinetics and whether the spatial nonuniformity of APDR promotes persistence of AF.BackgroundA steeply sloped APDR curve is known to be an important determinant of the induction of more complex action potential duration (APD) dynamics and fibrillation.MethodsPatients with chronic atrial fibrillation (CAF) (n = 18), paroxysmal atrial fibrillation (PAF) (n = 14) and normal control subjects (n = 9) were studied. The monophasic action potential duration at 90% repolarization (APD90) and the effective refractory period (ERP) were measured at six sites in the right atrium. After AF was electrically converted, APDR was assessed by delivering a single extrastimulus after a train of stimuli at a cycle length of 600 ms (S1S2) at six different sites of the right atrium, as well as rapid pacing at cycle lengths that induced APD alternans.ResultsThe APD90and ERP in patients with CAF were shorter than those in patients with PAF and control subjects (p < 0.05); however, the dispersions of APD90and ERP in each group were similar. The maximal slopes of APDR by S1S2and rapid pacing in patients with CAF (1.2 ± 0.4 and 1.7 ± 0.2) and PAF (1.1 ± 0.4 and 1.3 ± 0.4) were higher than those in control subjects (0.5 ± 0.3 and 0.8 ± 0.2, respectively; p < 0.01). The maximal slope obtained by S1S2did not differ from that obtained by rapid pacing in any group. The inter-regional difference of the maximal slope in patients with CAF (1.6 ± 0.4, p < 0.05) was greater than that in patients with PAF (1.2 ± 0.3, p = NS vs. control) and control subjects (0.4 ± 0.2).ConclusionsAtrial fibrillation was related to steeply sloped (>1) APDR kinetics. The spatial dispersion of APDR in patients with chronic AF was greater than that of patients with paroxysmal AF and control subjects, indicating that the heterogeneity of APDR of the atrium plays an important role in the persistence of AF.