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We report the results of the dating of a pine tree (Pinus densiflora) from Yeongwol, Korea. The age of the tree was estimated to be in the range of hundreds of years, however, the tree had been broken by a strong wind in March 2010 and now only the stump of the tree is left. At the time of sampling in 2014, there were several decayed parts in the stump, so using the usual dendrochronological method (i.e. ring counting) for dating was difficult. However, we found a small wood sample with tree rings near the center of the stump that could be used for radiocarbon wiggle-match dating. Radiocarbon dates were determined using Accelerator mass spectrometry (AMS). The IntCal13 curve was used to calibrate the radiocarbon dates, and the wiggle matching technique was used to reduce the error of the calibrated ages. Based on the dating results, we suggest that the pine tree is approximately 300 years or older.

HEP(Head Electric Power) system, supplying 3-phase service power to the coach vehicles, is a kind of special auxiliary power equipment which is boarded on 8200 series electric locomotives in KORAIL. This equipment shares high voltage DC link with a main propulsion converter/inverter systems. It was difficult to use high frequency PWM technique so that GTO has been used as a power device same like the main power system. Due to low PWM frequency(300Hz) of HEP inverter, the output voltage has less power quality comparing to normal SIV(Static Inverter) system. In this paper, an optimal PWM strategy is presented for new IGBT type HEP inverter system. Several PWM techniques were investigated to improve output voltage quality under fixed lower filter inductance and not high PWM frequency. Finally PC simulations have been done to clarify its availability.

Conventional power conversion unit that is a major part of the propulsion system has applied GTO thyristor as a switching semiconductor device of main circuit since introduction of the 8200 electric locomotive. But problem that quick maintenance is difficult and its cost is increasing occurs because major components of the power conversion unit are slowly discontinued. To solve these, in this paper, it was analyzed the response characteristic of the propulsion system modeling of the 8200 electric locomotive using IGBT which is applied recently to ensure propulsion control technology. As results of response for a Propulsion system modeling, it show that a power conversion unit is controlled by PLL(Phase-locked loop) and SVPWM(Space Voltage PWM) respectively.

In this paper, proper length of neutral section and neutral section system configuration is proposed to minimize accidents if ATO urban railway vehicle stops maintaining the leading vehicles in air section at regular intervals. When considering the minimum voltage sensing of power conversion unit in the urban railway vehicle, the effective length of 14,280[mm] with neutral section can be minimized damage due to high current because the urban railway vehicle is very little present chance compare neutral section with pantograph interval installed on a unit vehicle. In addition, uplift of catenary line and contact wire consider to minimize damage. The result of theoretical review, as the proposed neutral section shorter, isolated neutral section is effective than the integrated neutral section.

The Noda epileptic rat (NER), a Wistar colony mutant, spontaneously has tonic-clonic convulsions with paroxysmal discharges. In the present study, we measured phasic and tonic γ-aminobutyric acid A (GABAA) current ( Itonic) in NER hippocampal dentate gyrus granule cells and compared the results with those of normal parent strain Wistar rats (WIS). Itonic, revealed by a bicuculline-induced outward shift in holding current, was significantly smaller in NER than in WIS ( P < 0.01). The frequency of inhibitory postsynaptic currents (IPSCs) was also significantly lower in NER than in WIS ( P < 0.05), without significant differences in the IPSC amplitude or decay time between WIS and NER. Itonic attenuation in NER was further confirmed in the presence of GABA transporter blockers, NO-711 and nipecotic acid, with no difference in neuronal GABA transporter expression between WIS and NER. Itonic responses to extrasynaptic GABAA receptor agonists (THIP and DS-2) were significantly reduced in NER compared with WIS ( P < 0.05). Allopregnanolone caused less Itonic increase in NER than in WIS, while it prolonged the IPSC decay time to a similar rate in the two groups. Expression of the GABAA receptor δ-subunit was decreased in the dentate gyrus of NER relative to that of WIS. Taken together, our results showed that a combination of attenuated presynaptic GABA release and extrasynaptic GABAA receptor expression reduced Itonic amplitude and its sensitivity to neurosteroids, which likely diminishes the gating function of dentate gyrus granule cells and renders NER more susceptible to seizure propagation.

Due to the increasing concerns about the buildings which have affected the global environment, most countries have enacted a regulation for the sustainability of domestic buildings. In 2008, the Korean government started to enact a regulation of apartment and office buildings for energy saving. Many research on the sustainable apartment building focuses on or larger type in response to market demand; therefore, small size type such as type needs to be researched. In addition, the research on the orientation and window to wall ratio of the building have been separately studied as a means of energy reduction; therefore, the research on correlation of the orientation and window to wall ratio hasn`t been fully explored yet. This paper analyzes the energy demand of the apartment building as the change of orientation and window to wall ratio among and type. In conclusion, when reducing the window to wall ratio, energy demand was reduced, except when the orientation of the building was between from +10 to -20 from the south.

In this paper, analysis method for current collection performance based on real-time current of catenary system is proposed. An innovative method based on track-side of railway system is used for measurement of currents for overhead contact line during the collection with pantograph. The evaluation of a qualitative ratio for current collection performance were conducted using proposed algorithm under various conditions such as laboratory and track-side. To check the validity of our approach, we compared between calculation results from current of contact wire and measurement results from arcing of pantograph using simulator in laboratory conditions. The results show that the behavior of current collection performance were analysis from currents of overhead contact line in AC electric railway system.

This paper presents the result of life-cycle cost (LCC) estimation for domestic products propulsion control system (motor block unit) of KTX-1 considering periodic maintenance. Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Life cycle costing includes the cost of concept design, development, manufacture, operation, maintenance and disposal. To estimate LCC for domestic products motor block unit, it was analyzed physical breakdown structure (PBS) on motor unit in view of maintenance cost and unit cost etc. As a results, life cycle cost on motor block unit increased moderately expect for periodical time when major parts are replaced at the same time. hereafter this results will be reflected in the domestic products being developed.

Overproduction and accumulation of melanin in the skin can lead to pigmentation disorders, such as freckles and melasma. Many researchers are studying the regulation of melanogenesis in the skin with the aim of developing whitening cosmetics. In this study, bioactivity-guided separation of the hexane fraction of Schisandra chinensis (Turcz.) Baillon extract yielded five major compounds, β-chamigrenal, α-ylangenol, gomisin N, gomisin A, and schisandrin. The structures were identified by using 1H-NMR and 13C-NMR spectroscopy and comparing the spectral data with published data. Melanogenesis inhibitory activity assay in alpha-melanocyte-stimulating hormone (α-MSH)-induced B16F10 mouse melanoma cells revealed that gomisin N was the active component and significantly inhibited melanin synthesis in a concentration-dependent manner. Thus, we evaluated the mechanism underlying its anti-melanogenic effect. Gomisin N inhibited the expression of tyrosinase and microphthalmia-associated transcription factor (MITF) in B16F10 cells, while it did not affect cAMP response element binding protein (CREB) phosphorylation. Additionally, gomisin N activated AKT phosphorylation, which inhibits MITF expression. Thus, our results strongly suggest that the active compound, gomisin N, has potential for use in cosmetics to reduce hyperpigmentation.

Although anxiety and depression have been classified as distinct traits of affective disorders, previous studies have reported their co-occurrence in subjects with migraine. However, few reports are available on the clinical implications of this comorbidity. This study is to assess the comorbidity of anxiety and depression in subjects with migraine and its clinical implications in a population-based sample from Korea.We selected Korean subjects aged 19-69 years by the stratified random sampling method, and evaluated them using a semi-structured interview, designed to identify headache type, anxiety, and depression. We used Goldberg Anxiety Scale questions and Patient Health Questionnnaire-9 for the diagnosis of anxiety and depression, respectively.Of the 2,762 participants who completed the interview, 147 subjects (5.4%) were classified as having a migraine during the previous year. Among these 147 subjects, 17 (11.6%) had anxiety and depression, 28 (19.0%) had anxiety alone, 9 (6.1%) had depression alone, and 93 (63.3%) had neither anxiety nor depression. Headache frequency per month was remarkably higher in subjects having migraine with anxiety and depression (median [25-75 percentile values], 8.0 [2.5-21.0]) than in those having migraine with anxiety alone (2.0 [1.0-5.0], p = 0.003), migraine with depression alone (1.0 [0.3-4.0], p = 0.001), and migraine without anxiety or depression (1.0 [0.3-3.0], p 0.001). The migraine with anxiety alone (7.0 [6.0-8.0], p = 0.011) group and migraine with anxiety and depression (7.0 [5.0-9.0], p = 0.018) group showed higher Visual Analogue Scale scores for pain intensity compare to migraine without anxiety or depression (6.0 [5.0-7.0]) group.Approximately 1/3 of migraineurs with anxiety had depression and 2/3 of migraineurs with depression had anxiety. Combination of anxiety and depression was associated with an increased headache frequency. Anxiety was associated with exacerbation of headache intensity.

Background We conducted the study to examine accuracy of the magnetoencephalography (MEG) spike source localization in presurgical evaluation of patients with medically refractory focal epilepsy. Methods Ten consecutive patients with refractory focal epilepsy who were candidates for two-stage surgery with long-term intracranial electroencephalography (ICEEG) monitoring were enrolled. Interictal MEG recordings with simultaneous scalp EEG were obtained within 7 days before the ICEEG electrode implantation. The location of each MEG spike source was quantitatively compared with ICEEG spike foci (focal area of interictal spikes) and ICEEG ictal foci (earliest cortical origin of seizures). Gyral-width concordance and sublobar concordance were also determined for all MEG spike sources. Gyral-width concordance was defined by distance of 15 mm or less between MEG spike sources and ICEEG spike foci or ICEEG ictal foci. Results Visual analyses of the MEG traces of all 10 patients revealed 292 spikes (29.2 ± 24.0 per patient). Spike yield of the MEG was similar to the simultaneously recorded scalp EEG. MEG spike sources were closely located with ICEEG spike foci (distance: 9.3 ± 10.8 mm). Clustered MEG spike sources were even closer to ICEEG spike foci (distance: 7.3 ± 6.4 mm). MEG spike sources, even clustered ones, were less concordant with ICEEG ictal foci and had significant longer distance from ICEEG ictal foci (distance: 21.5 ± 15.6 mm for all sources, 19.7 ± 13.7 mm for clustered sources). Gyral-width concordance rate and sublobar concordance rate were also higher with ICEEG interictal spike foci than with ICEEG ictal foci. On the other hand, 53.4% of interictal spike foci from ICEEG were not detected by interictal MEG recordings. Conclusions MEG spike sources, especially clustered ones, from interictal recording could localize the irritative zone of ICEEG with a high accuracy. However, MEG spike sources have relatively poor correlation with seizure onset zone and lower sensitivity in identifying all irritative zones of ICEEG. This limitation should be considered in the interpretation of MEG results.

BACKGROUND:Various stimuli can trigger migraines in susceptible individuals. We examined migraine trigger factors by using a smartphone headache diary application. METHOD:Episodic migraineurs who agreed to participate in our study downloaded smartphone headache diary application, which was designed to capture the details regarding headache trigger factors and characteristics for 3 months. The participants were asked to access the smartphone headache diary application daily and to confirm the presence of a headache and input the types of trigger factors. RESULTS:Sixty-two participants kept diary entries until the end of the study. The diary data for 4,579 days were analyzed. In this data set, 1,099 headache days (336 migraines, 763 non-migraine headaches) were recorded; of these, 772 headache events had with trigger factors, and 327 events did not have trigger factors. The common trigger factors that were present on headache days included stress, fatigue, sleep deprivation, hormonal changes, and weather changes. The likelihood of a headache trigger was 57.7% for stress, 55.1% for sleep deprivation, 48.5% for fatigue, and 46.5% for any trigger. The headaches with trigger factors were associated with greater pain intensity (p

Previous studies have demonstrated an association of osteopenia/osteoporosis with idiopathic benign paroxysmal positional vertigo (BPPV). Since vitamin D takes part in the regulation of calcium and phosphorus found in the body and plays an important role in maintaining proper bone structure, decreased bone mineral density in patients with BPPV may be related to decreased serum vitamin D. We measured the serum levels of 25-hydroxyvitamin D in 100 patients (63 women and 37 men, mean age ± SD = 61.8 ± 11.6) with idiopathic BPPV and compared the data with those of 192 controls (101 women and 91 men, mean age ± SD = 60.3 ± 11.3) who had lived in the same community without dizziness or imbalance during the preceding year. The selection of the controls and acquisition of clinical information were done using the data from the Fourth Korean National Health and Nutrition Examination Survey, 2008. The serum level of 25-hydroxyvitamin D was lower in the patients with BPPV than in the controls (mean ± SD = 14.4 ± 8.4 versus 19.1 ± 6.8 ng/ml, p = 0.001). Furthermore, patients with BPPV showed a higher prevalence of decreased serum vitamin D (

This paper presents the application algorithm for speed control of Switched Reluctance Motor. The conventional PI controller has been widely used in industrial applications. But it is very difficult to find the optimal PI control gain. Fuzzy control does not need any model of plant. It is based on plant operator experience and heuristics. The proposed fuzzy logic modifier increases the control performance of conventional PI controller. Simulation and experimental results show that the proposed fuzzy control method was superior to the conventional PI controller in the respect of system performance. The experiments are performed to verify the capability of proposed control method on 6/4 salient type SRM.

It is important to consider supply voltage stability in case of design and construction of a substation at electric railway because a urban transit is operated by electricity and it is driven simultaneous in the same section. This paper study on variation of the dynamic characteristic of supply voltage according to the track environment and spatial distribution as driving of urban transits. Simulation tool, TOM(Train Operations Model) software is used to ensure stability of feeder system being used around the world. As results of simulation, voltage of the contact wire is in limits on driving operation diagram of urban transits. Also, it has confirmed that there is a correlation the phase current, depending on the speed of urban transit and track environment like vertical gradients and curve radius.

Urban rail transit tends to global grounding system in order to control ground potential rise and potential differences between electric equipments. In addition, global grounding system can discharge the large capacity surge current to the ground safely. Since some railway electric equipments are installed all section of line, the global grounding system connected with the connecting grounding wire is more effectively. However, if the fault occurred in the connecting grounding wire area, some dangerous voltage is generated. So, the installation of additional grounding rod will be required. In this study, the global grounding system is simulated using CDEGS program to analyze the divergence spacing of additional ground rod depending on dangerous electric potential characteristics. Grounding net of the each station is modelled in depending on the size of the platform, and the spacing of the connecting grounding rod are compared 50m, 100m, 250m and 400m. Simulation results considering of earth resistivity and underground condition of the connecting grounding wire, spacing of the connecting grounding rod is that less than 250m to spacing of the ground rod was appropriately confirmed.

The current collection between pantograph and contact wire is a more critical component for need to train speed up in electric railway. The basic purpose of this paper is to establish a measure of determining arc by developing an arc detector assessment system. The system was designed under conditions of EN 50317 and simulations were conducted using the developed device. According to the results, it was possible to conduct certification tests following regulations of international standards. To check the validity of our approach for the intended application, we analysis contact loss of catenary system using developed arcing measurement system in Korea. The proposed arcing measurement system is expected to enhance precision of current collection quality performance assessment methods at high-speed lines and conventional lines.

Power line communication(PLC) is a kind of communication technology, was made use of controling a frequency narrow band, but as the PLC technology developing, in the near future get to the commercial step that is broadband PLC upto 30 ㎒. This paper deals with the PLC of electric railway using capacitive signal coupler. An AC arrester for catenary is used as a capacitive signal coupler, has the characteristic of capacitor. As a result of field test, a messenger wire used PLC contain much of conducted noise about overall frequency band and also signal attenuation rate increased with increasing frequency between two points. and the communication speed of PLC used messenger wire is 793kbps at a distance of 40m. Experimental results show the possibility of PLC using a messenger wire and an AC arrester for catenary at electric railway.Key Words : Power line communication, Capacitive signal coupler, AC arrester, Attenuation, Messenger wire† 교신저자, 정회원 : 한국교통대 철도전기전자공학과 부교수․공박E-mail : goldmoon@krc.ac.kr*정 회 원 : 한국교통대 철도운전시스템공학과 교수․공박** 정 회 원 : 한국교통대 철도전기전자공학과 교수․공박***정 회 원 : 한국교통대 철도차량시스템공학과 부교수․공박 접수일자 : 2011년 11월 25일 최종완료 : 2012년 1월 27일

For a real quadratic field $k=\mathbb {Q}(\sqrt {pq})$, let tk be the exact power of 2 dividing the class number hk of k and ηk the fundamental unit of k. The aim of this paper is to study tk and the value of Nk/ℚ(ηk). Various methods have been successfully applied to obtain results related to this topic. The idea of our work is to select a special circular unit ℰk of k and investigate C(k)=〈±ℰk 〉. We examine the indices [E(k):C(k)] and [C(k):CS (k)] , where E(k) is the group of units of k, and CS (k) is that of circular units of k defined by Sinnott. Then by using the Sinnott’s index formula [E(k):CS (k)]=hk, we obtain as much information about tk and Nk/ℚ (ηk) as possible.

Background and purpose New-onset headache in elderly patients is generally suggestive of a high probability of secondary headache, and the subtypes of primary headache diagnoses are still unclear in the elderly. This study investigated the characteristics of headache with an older age at onset (≥65 years) and compared the characteristics between younger and older age groups. Methods We prospectively collected demographic and clinical data of 1,627 patients who first visited 11 tertiary hospitals in Korea due to headache between August 2014 and February 2015. Headache subtype was categorized according to the International Classification of Headache Disorders, Third Edition Beta Version. Results In total, 152 patients (9.3%, 106 women and 46 men) experienced headache that began from 65 years of age [elderly-onset group (EOG)], while the remaining 1,475 patients who first experienced headache before the age of 65 years were classified as the younger-age-at-onset group (YOG). Among the primary headache types, tension-type headache (55.6% vs. 28.8%) and other primary headache disorders (OPH, 31.0% vs. 17.3%) were more common in the EOG than in the YOG, while migraine was less frequent (13.5% vs. 52.2%) (p=0.001) in the EOG. Among OPH, primary stabbing headache (87.2%) was more frequent in the EOG than in the YOG (p=0.032). The pain was significantly less severe (p=0.026) and the frequency of medication overuse headache was higher in EOG than in YOG (23.5% vs. 7.6%, p=0.040). Conclusions Tension-type headache and OPH headaches, primarily stabbing headache, were more common in EOG patients than in YOG patients. The pain intensity, distribution of headache diagnoses, and frequency of medication overuse differed according to the age at headache onset.

This paper estimates the life cycle cost(LCC) of a propulsion control system using the maintenance information in the high speed train(KTX-1). Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Until now, most life cycle cost of the system has been studied as a whole system viewpoint. But in case of railway industry, LCC studies are needed on the subsystem like a propulsion control system because subsystems are developed continuously localization. This paper proposes the life cycle cost model which fitted to estimate life cycle cost (LCC) using maintenance information manual. As a result, LCC on propulsion control system increased moderately expect for periodical time when major parts are replaced at the same time. Results will be reflected in the development of domestic products.

BLDC motor is used in a wide variety of industrial and servo applications. Its features and advantages mainly consist in high value of torque/inertia ratio, high efficiency with speed range and high dynamic performance. This paper deals with the speed control of a trapezoidal type brushless DC motor using Fuzzy PI controller. The conventional PI controller has been widely used in industrial applications. If we select a optimal PI control gain, the PI controller shows very good control performance. But it is very difficult to find the optimal PI control gain. Fuzzy control does not need any model of plant and is basically adaptive and gives robust performance for plant parameter variation. Therefore the combinations of conventional PI controller and fuzzy controller seem to be very effective. This paper deals with PI controller with 4-rule based fuzzy controller. The proposed fuzzy PI controller increases the control performance of the conventional PI controller. Simulation and experimental results show that fuzzy PI controller has a good robustness regarding the improper tuned PI controller.

For an abelian number field k, let CS(k) be the group of circular units of k defined by Sinnott, and CW(k) be that suggested by Washington. In this paper, we construct an element Θ˜=Θ˜(k) in CW(k) for a real subfield k of conductor p1e1p2e2. We will see that the order of Θ˜ in the factor group CW(k)/CS(k) can be very large. As an application, we derive some information about the class number of k for special cases.

We sought to investigate the peripheral nerve excitability property of early diabetic neuropathy (DN) and provide a logical hypothesis regarding the pathophysiology of subclinical/early stage of DN. The automated nerve excitability test (NET) utilizing the threshold tracking technique (TTT) was performed to measure multiple excitability indices in 30 early DN and 30 normal subjects. Early DN was defined as N0 or N1 stage of Dyck's staging method. The protocols calculated strength-duration time constant (SDTC) from duration–charge curve, parameters of threshold electrotonus (TE) and current–threshold relationship (CTR) from sequential sub-threshold current, and recovery cycle (RC) from double supra-threshold stimulation. Each parameter of test was co-analyzed with clinical and laboratory data including age, sex, BMI, HgbA1c, lipid profile, and estimated glomerular filtration rate (eGFR). Compared to normal or N0 groups, N1 group had ‘fanning-in’ phenomenon in TE, increased refractory period, and decreased supernormality/subnormality. Linear regression showed that parameters associated with vascular factor were significantly related with STDC: absolute TG values were positively associated with STDC, whereas eGFR values were inversely related with STDC. Nerve excitability can be altered even in the early mild DN. The pattern of alteration suggests depolarizing nerve or nerve ischemia in pathophysiology of subclinical/early DN.

In this paper we propose network design for power line communication of electric railway using messenger wire. we carried out feasibility study on the power line communication(PLC) using Contact wire and messenger wire which are required at electric railway. First of all, full-duplex data communication was implemented using coupler which is suspended on messenger wire at non-voltage state. We verified data transfer rate was found to be good, and then proposed a design example of PLC network as the main components for PLC. we will study continuously make an effort to verify on the network design of PLC for further study.Key Words : Messenger Wire, PLC(Power Line Communication), Electric Railway, Coupler, Contact Wire 본 논문은 한국건설기술평가원의 미래철도기술개발사업의 연구비지원에 의해 수행되었음. * 교신저자 : 김재문(goldmoon@krc.ac.kr)접수일 10년 09월 16일 수정일 10년 10월 13일 게재확정일 10년 10월 15일 1. 서론 국내 철도산업은 ‘04년 고속철도(KTX) 상용화를 계기로 전기철도 확충, 철도부품의 국산화와 지자체를 중심으로 경량전철 도입 등 활발한 연구개발이 이루어지고 있다. 특히 철도신호 및 통신분야인 경우 국내 IT기술이 발달됨에 따라 CBTC(Communication Base Train Control), 무선영상 전송 시스템 개발 등 이를 접목한 새로운 융복합 기술이 대두되고 있다.한편 전력선 통신은 고속의 데이터 전송에 대한 수요를 충족할 수 있는 기술로 주로 전력회사의 미터 계측용이나 배전 자동화용으로 많이 연구되어 왔으며, 많은 제한적인 이유 때문에 사용이 극히 일부분의 응용에 적용되어 왔다. 최근에는 전력선 통신 기술은 고속 데이터 통신을 위한 새로운 기술로 부각되고 있으며, 디지털 변조 기술의 발전에 따른 통신 속도 및 신뢰성의 향상, 인터넷의 급속한 발전으로 통신 매체로써 전력선이 각광을 받고 있다. 특히 기존의 전력 시설을 활용하기 때문에 비용이 적게 들고 별도의 설치가 없거나 기간이 매우 짧아 새로운 고속 접속망을 구축하는 것보다는 비용측면에서 효율적인 것으로 알려져 있다[1-3]. 그럼에도 불구하고 전기철도 산업분야에서 전력선 통신을 적용한 국내외 사례가 없는 실정이며, 철도차량 간 SNMP 기반 전력선 통신[4] 등 연구가 이루러지고 있다.

This paper presents novel topologies implementation for Switched Reluctance Motor (SRM) drive used in commercial applications. For effective utilization of the developed system, a novel direct current controlled PWM scheme is designed and implemented to produce the desired dynamic speed characteristic. In comparison to conventional asymmetric converter topology, it can minimize entire system costs by reducing numbers of power semiconductors. Therefore, it may open up investigation of a new way for SRM to compete with other ac motors such as induction motors, brushless dc motors, etc. The validity of the proposed method is verified through theoretical explanation and experimental results.

We demonstrated that room temperature plasma could be used for tooth bleaching. A nonthermal, atmospheric pressure, helium plasma jet device was developed to enhance the tooth bleaching effect of hydrogen peroxide (H(2)O(2)). All teeth were sectioned sagittally into halves, which were assigned randomly to either the experimental group or the control group. The experimental group was treated with H(2)O(2) (28%, 20 microL every 30 seconds) plus plasma (5 W) for 10 minutes; the control group was treated with H(2)O(2) alone for the same duration. Removal of the tooth surface protein was demonstrated by scanning electron microscopy images and Ponceau staining. Production of hydroxyl radicals (.OH) was measured by using electron spin resonance spin-trapping. Combining plasma and H(2)O(2) improved the bleaching efficacy by a factor of 3 compared with using H(2)O(2) alone. Tooth surface proteins were noticeably removed by plasma treatment. When a piece of tooth was added to a solution of H(2)O(2) as a catalyst, production of *OH after plasma treatment was 1.9 times greater than when using H(2)O(2) alone. We suggest that the improvement in tooth bleaching induced by plasma is due to the removal of tooth surface proteins and to increased *OH production.

Summary Purpose: To evaluate the efficacy and safety of pregabalin (PGB) as adjunctive therapy, using a flexible-dosing schedule in Korean patients with refractory partial-onset seizures. Methods: This randomized, double-blind (DB), placebo-controlled trial consists of a 6-week baseline, a 12-week DB treatment, and a 1-week taper phase. Patients having recurrent partial seizures (≥4 seizures during baseline phase) under adequate pharmacotherapy were recruited to be randomized to PGB or placebo (PLC) in a 2 to 1 ratio. Starting dose was 150 mg/day, increased every 2 weeks by 150-mg/day increments up to maximum dose of 600 mg/day. The primary efficacy parameter was response ratio (RRatio) for all partial seizures. Results: A total of 178 patients (119 in PGB, 59 in PLC) were assigned to the study. Median daily doses of PGB and PLC were 367 and 420 mg/day, respectively. RRatio least squares (LS) mean was −35.8 in the PGB group and −23.2 in the PLC group, with estimated difference in RRatios being −12.6 [95% confidence interval (CI): −22.7 to −2.5, p = 0.015] in the intent-to-treat (ITT) population. Analysis of secondary efficacy measures showed a general trend favoring PGB over PLC. Seventy-seven patients (64.7%) in the PGB group and 18 patients (30.5%) in the PLC group developed adverse events (AEs) related to the study drug. Seven patients (5.9%) in the PGB group discontinued the study prematurely because of AEs. In the post hoc analysis, a significant weight gain (≥7% of baseline body weight) was found in 24.8% of patients taking PGB, which was more frequent in patients with a lower body mass index (BMI ≤20). Discussion: PGB was effective and easily tolerable as add-on treatment in an Asian population with refractory partial-onset seizures.

Motivated by XTR cryptosystem which is based on an irre- ducible polynomial x 3 i cx 2 + c p x i 1 over Fp2, we study polynomials of the form F(c;x) = x 3 i cx 2 + c q x i 1 over Fq2 with q = p m . In this paper, we establish a one to one correspondence between the set of such polynomials and a certain set of cubic polynomials over Fq. Our ap- proach is rather theoretical and provides an e-cient method to generate irreducible polynomials over Fq2.

Objective Increased arterial stiffness is an independent predictor of cardiovascular diseases in hypertensive patients. Hypertension and aging can cause similar damage to small vessel walls. The objective of this study was to determine relationship between arterial stiffness measured by brachial–ankle pulse wave velocity (baPWV) and the risk of cerebral small vessel disease (SVD) in elderly people with hypertension. Methods We studied 196 elderly subjects with hypertension (≥50 years of age) who had neither large vessel stroke nor cardiac embolism. These patients were divided into three groups based on the results of brain MRI: (1) those with first-ever small vessel stroke; (2) those with asymptomatic subcortical ischemia; and (3) a control group with hypertension. Results The baPWV was significantly increased in the patients with first-ever small vessel stroke or asymptomatic subcortical infarction when compared to the control group, after adjusting for systolic blood pressure (SBP), pulse pressure (PP), and hs-CRP (p = 0.005). Among subjects with SVD on MRI, the number of lacunar infarcts (LIs) ≥ 5 was significantly related to a higher baPWV (p = 0.02). The relationship between the severity of periventricular white matter hyperintensities (PWMH) and the degree of baPWV became insignificant after adjustment for age. Conclusion Increased baPWV was significantly associated with the risk of SVD in elderly persons with hypertension. Therefore, the measurement of baPWV could be used to predict SVD.

This parer presents novel topologies implementation for Switched Reluctance Motor (SRM) drive used in commercial applications. For effective utilization of the developed system, a novel direct current controlled PWM scheme is designed and implemented to produce the desired dynamic speed characteristic. In comparison to conventional asymmetric converter topology, it can minimize entire system costs by reducing numbers of power semiconductors. Therefore, it may open up investigation of a new way for SRM to compete with other ac motors such as induction motors, brushless dc motors, etc. The validity of the proposed method is verified through theoretical explanation and experimental results.

In this paper, novel topology for fast response of various loads is proposed. The windup phenomenon appears and results in performance degradation when the PI controller output is saturated. A new anti-windup PI controller is proposed to improve the control performance of variable speed motor drives, and it is experimentally applied to the speed control of a hysteresis current-controlled SRM driven by an asymmetry bridge converter. The experimental results show that the speed response has much improved performance, such as small overshoot and fast settling time, over the conventional PI control.

Background A “Probable headache disorder” is diagnosed when a patient’s headache fulfills all but one criterion of a headache disorder in the 3rd beta edition of the International Classification of Headache Disorder (ICHD-3β). We investigated diagnostic changes in probable headache disorders in first-visit patients after at least 3 months of follow-up. Methods This was a longitudinal study using a prospective headache registry from nine headache clinics of referral hospitals. The diagnostic change of probable headache disorders at baseline was assessed at least 3 months after the initial visit using ICHD-3β. Results Of 216 patients with probable headache disorders at baseline, the initial probable diagnosis remained unchanged for 162 (75.0 %) patients, while it progressed to a definite diagnosis within the same headache subtype for 45 (20.8 %) by fulfilling the criteria during a median follow-up period of 6.5 months. Significant difference on the proportions of constant diagnosis was not found between headache subtypes (P 3 and ≤ 6 months vs. > 6 and ≤ 10 months) in probable migraine, probable TTH, and probable OPHD, respectively. Conclusions In this study, a probable headache diagnosis, based on ICHD-3β, remained in approximately three-quarters of the outpatients; however, diagnostic stability could differ by headache recurrence and subtype. Probable headache management might have to consider these differences.

Background Recent studies have shown an association between migraine and restless legs syndrome (RLS). However, migraine prevalence peaks from the 20s to 40s whereas RLS prevalence peaks after the 50s. Despite this, reports on how migraine and RLS may be associated by age is limited. Therefore, the purpose of this study is to investigate the comorbidity between migraine and RLS according to age. Methods We selected a stratified random population sample of Koreans aged 19 to 69 years and evaluated them with a 60-item semi-structured interview designed to identify RLS, headache type, and clinical characteristics of migraine. To assess the association between migraine and RLS according to age, we divided participants into 5 age groups (19–29, 30–39, 40–49, 50–59, and 60–69 years) and analysed each group. Results Subjects with migraine showed an increased RLS prevalence in the 19–29 (Odds ratio [OR] = 6.6, 95 % confidence interval [CI] = 1.2–36.8) and 40–49 (OR = 6.7, 95 % CI = 1.5–33.5) age groups compared to non-headache controls but failed to showed a significant association in the 50–59 (OR = 1.1, 95 % CI = 0.2–5.6) and 60–69 (OR = 0.4, 95 % CI = 0.1–4.0) age groups. Migraineurs with 1–10 (12.5 %, OR = 2.0, 95 % CI = 1.3–3.2, p = 0.003) and >10 (12.5 %, OR = 2.5, 95 % CI = 1.0–5.6, p = 0.038) attacks per month showed an increased RLS prevalence compared to migraineurs with

Background Vestibular migraine (VM), the common term for recurrent vestibular symptoms with migraine features, has been recognized in the appendix criteria of the third beta edition of the International Classification of Headache Disorders (ICHD-3β). We applied the criteria for VM in a prospective, multicenter headache registry study. Methods Nine neurologists enrolled consecutive patients visiting outpatient clinics for headache. The presenting headache disorder and additional VM diagnoses were classified according to the ICHD-3β. The rates of patients diagnosed with VM and probable VM using consensus criteria were assessed. Results A total of 1414 patients were enrolled. Of 631 migraineurs, 65 were classified with VM (10.3%) and 16 with probable VM (2.5%). Accompanying migraine subtypes in VM were migraine without aura (66.2%), chronic migraine (29.2%), and migraine with aura (4.6%). Probable migraine (75%) was common in those with probable VM. The most common vestibular symptom was head motion-induced dizziness with nausea in VM and spontaneous vertigo in probable VM. The clinical characteristics of VM did not differ from those of migraine without VM. Conclusion We diagnosed VM in 10.3% of first-visit migraineurs in neurology clinics using the ICHD-3β. Applying the diagnosis of probable VM can increase the identification of VM.

Questionnaire in English.

Background Although anxiety and depression have been classified as distinct traits of affective disorders, previous studies have reported their co-occurrence in subjects with migraine. However, few reports are available on the clinical implications of this comorbidity. This study is to assess the comorbidity of anxiety and depression in subjects with migraine and its clinical implications in a population-based sample from Korea. Methods We selected Korean subjects aged 19–69 years by the stratified random sampling method, and evaluated them using a semi-structured interview, designed to identify headache type, anxiety, and depression. We used Goldberg Anxiety Scale questions and Patient Health Questionnnaire-9 for the diagnosis of anxiety and depression, respectively. Results Of the 2,762 participants who completed the interview, 147 subjects (5.4%) were classified as having a migraine during the previous year. Among these 147 subjects, 17 (11.6%) had anxiety and depression, 28 (19.0%) had anxiety alone, 9 (6.1%) had depression alone, and 93 (63.3%) had neither anxiety nor depression. Headache frequency per month was remarkably higher in subjects having migraine with anxiety and depression (median [25–75 percentile values], 8.0 [2.5–21.0]) than in those having migraine with anxiety alone (2.0 [1.0–5.0], p = 0.003), migraine with depression alone (1.0 [0.3–4.0], p = 0.001), and migraine without anxiety or depression (1.0 [0.3–3.0], p

Objective : To differentiate between primary and secondary bilateral synchrony (PBS and SBS, respectively) in generalized spike-and-wave discharges (GSWD), we applied independent component analysis (ICA) to GSWD, and analyzed the characteristic patterns of independent components. Methods : EEGs from 19 patients with GSWD (9 PBS patients, 10 SBS patients) were studied. Thirty GSWD epochs were selected and concatenated to construct an EEG data matrix that was subjected to ICA. Selected independent components were localized by mapping them on a spherical model of the head by means of brain electrical source analysis (BESA) to define dipole sources. Results : Epileptic components of GSWD were clearly separated by the ICA algorithm in all patients. Between one and three components per patient were responsible for GSWD. In PBS patients, 70.6% of the independent components had dipole sources within the dorsolateral frontal region, and 56.5% of the independent components in SBS patients were within the medial frontal region ( P =0.012). The orientation of all of the independent components in PBS patients was radial, whereas 47.8% of the independent components in SBS patients were tangential; this difference was statistically significant ( P =0.001). Conclusions : Spatiotemporal decomposition of GSWD by using ICA might be helpful for differentiating SBS from PBS. Significance : The localization of the dipole sources of the independent components may provide insight into the pathophysiological origins of GSWD.

Trochleitis is an uncommon disorder that is defined as inflammation of the superior oblique tendon trochlea apparatus and is characterized by pain, point tenderness over the trochlea, and/or localized swelling [1, 2]. In absence of clear findings suggestive of inflammation on blood test and radiology, this characteristic orbital pain around the trochlea with tenderness and exacerbation during upward gaze is called a primary trochlear headache or trochleodynia [3, 4]. In addition to the characteristic pain, trochleodynia can be accompanied by migrainous headache, ptosis, and conjunctival injection [2–4]. However, trochleodynia presenting with diplopia is rare. Herein, we report a patient with fourth nerve palsy associated with primary trochlear headache. A 29-year-old man presented with binocular vertical diplopia and left-side periocular pain for 4 days, which occurred after 1 day of migrainous headache. The migraine disappeared spontaneously with supportive care. However, the concurrent dull headache, periocular pain, and diplopia were not improved by analgesics or triptans. He denied diurnal variation of these symptoms. The periocular pain was exacerbated by eye movements, especially elevation. Examination of external eye did not show abnormal findings such as conjunctival injection, chemosis, proptosis, and periorbital edema. Painful tenderness was evoked by compression over the trochlear area (a score of 8 on the visual analogue scale; Fig. 1a). He had no medical history of hypertension or diabetes mellitus. He also denied any head trauma or ocular operation history. The vital signs were stable. His head was tilted rightward (Fig. 2) and hypertropia of the left eye (2 prism diopter, PD) was increased on adduction (3 PD), depression (3 PD), and leftward head tilt (4 PD; Fig. 2). The fundus photography shows no abnormal ocular torsion. These findings were most consistent with left trochlear nerve palsy. Other findings of neurological and neuro-ophthalmological examinations were normal. The results of laboratory evaluations, including autoimmune disease and vasculitis, were normal. There were also no remarkable findings that could explain his neurological deficits on MRI of the brain and orbit (Fig. 3). We diagnosed him as having primary trochlear headache with trochlear nerve palsy. The patient was injected with 3 mg of dexamethasone and 3 mg of methylprednisolone (final volume, 1 ml) targeted to the symptomatic trochlea (Fig. 1b). Periocular pain and tenderness were resolved within 48 h, and the diplopia gradually improved over several days. Our patient showed trochlear nerve palsy with focal tenderness in the trochlea, which was responsive to local steroid injection. Trochleodynia is a pain originating in the trochlear region that is felt in the upper-inner angle of the orbit and typically exacerbates upon elevation or palpation [4, 5]. Trochleitis is a syndrome of inflammatory K. J. Lee S.-H. Jeong (&) A. Y. Lee J.-M. Kim Department of Neurology, Chungnam National University Hospital, 640, Daesa-dong, Joong-ku, Daejeon 301-721, Korea e-mail: mseaj@hanmail.net

Cytochrome P4502C9(CYP2C9) is largely responsible for terminating anticoagulant effect by hydroxylation of S-warfarin to inactive metabolites. Mutations in the CYP2C9 gene result in the expression of allelic variants, CYP2C9*2 and CYP2C9*3 with reduced enzyme activity compared to wild type CYP2C9*1. The aim of this study was to assess relationship between requirement of warfarin dose and polymorphism in CYP2C9 in Korean population. Patients on warfarin therapy for longer than 1 year were included from July 1999 to December 2000 and categorized as one of four groups; regular dose non-bleeding, regular dose bleeding, low dose non-bleeding and low dose bleeding. Low dose was defined as less than 10 mg/week for 3 consecutive monthly follow-ups. Bleeding complications included minor and major bleedings. Blood samples were processed for DNA extraction, genotyping and sequencing to detect polymorphism in CYP2C9. Demographic data, warfarin dose per week, prothrombin time (INR), indications and co-morbid diseases were assessed for each group. Total 90 patients on warfarin were evaluated; The low dose group has taken warfarin 7.6 +/- 1.7 mg/week, which was significantly lower than 31.4 +/- 0.9 mg/week in the regular dose group (p0.0001). The measured INR in the low dose group was similar to that of the regular dose group (2.3 +/- 0.7 vs. 2.3 +/- 0.6, p=0.9). Even though there was a higher possibility of CYP2C9 variation in the low dose group, no polymorphism in CYP2C9 was detected. All patients were homozygous C416 in exon 3 for CYP2C9*2 and A1061 in exon 7 for CYP2C9*3. The DNA sequencing data confirmed the homozygous C416 and A1061 alleles. In conclusion, polymorphism in CYP2C9 is not a critical factor for assessing warfarin dose requirement and risk of bleeding complications in a Korean population.

Purpose: A multicentre open clinical trial was conducted to evaluate the clinical usefulness of a slower titration of topiramate (TPM) to 300 mg /day as adjunctive therapy for medically intractable partial epilepsies.Methods: Ninteen centres participated in the trial. Study patients had to have had two or more seizures per 4 weeks whilst taking maximum tolerated doses of one but not more than two anti-epileptic drugs. The starting dose of TPM was 25 mg /day and the dose was increased weekly by 25 mg /day until 100 mg /day was reached. Thereafter TPM was increased by 50 mg /day weekly up to the target dose of 300 mg /day, which was followed by an 8 week maintence phase. Seizure outcomes were measured by intention-to-treat analysis (ITTA)Results: Two hundred and thirteen patients entered the study. Median seizure frequency reduction rate was 44.8%, responder rate was 47.6%, and seizure free rate was 9.0%. These results were comparable to that of TPM 600 mg /day in our previous controlled trial. In subgroup analysis, seizure free rate was higher in those patients with a lower baseline seizure frequency rate. Seventeen patients (8.0%) were prematurely withdrawn from the study due to adverse events (AE) or lack of effect. One or more AEs were reported in 22% of patients, with dizziness being the most frequent AE. Other AEs occurred in less than 5% of patients.Conclusion: TPM 300 mg /day was effective and in conjunction with a slower dose-titration, markedly reduced the incidence of AEs, compared with previous study.

Objective: The effect of valproate (VPA) on human electroencephalography (EEG) was studied using nonlinear dynamics analysis to investigate changes in brain complexity. Methods: We propose a spatial linear mode complexity (SLMC) measure to quantify the complexity of spatial linear modes in multichannel EEGs. Nine patients with complex partial seizures who had not previously been exposed to antiepileptic drugs (AEDs) were included in this study. Eighteen-channel EEG data were collected before and after VPA therapy. Changes in brain complexity were examined using the proposed SLMC measure, which reflects brain complexity. Fifteen normal, healthy subjects were included as a control group. To compare SLMC with spectral analysis, we performed spectral analysis within the conventional frequency bands. Results: Spectral analysis showed that the patient group had decreased relative power of the alpha2 band in the T7, P3, O1 and C4 leads before VPA treatment and an increased relative theta power in the O1 lead relative to the control group. However, no significant changes occurred in any lead at any frequency band after VPA treatment. The mean SLMC value was significantly lower in the patient group before treatment than in the control group (p = 0.026). The average SLMC value for all patients increased after treatment and neared that of the control group, although statistical significance was not attained (p = 0.074). Conclusions: These results suggest that epilepsy patients have interictal abnormalities that are demonstrated by reduced brain complexity, and that VPA partially reverses this trend. Nonlinear analysis of EEG data may be useful in evaluating the effect of AEDs.

Juvenile myoclonic epilepsy (JME) is an idiopathic, age-related generalized epileptic syndrome. Status epilepticus (SE) in JME is very rare, and little is known about its etiology. We report 2 cases of adult patients, retrospectively diagnosed as JME by non convulsive status epilepticus which occurred for the first time. One patient was a 52-year-old woman who was presented with confusion and brief generalized tonic-clonic seizure (GTCS) for the first time. The other patient, a 39 year-old woman, visited the ER with transient LOC following confused mental state. Electroencephalograms of both patients repetitively showed generalized polyspikes and slow waves which were disappeared after IV injection of lorazepam. With careful history taking, both of them the patients were diagnosed as JME, and the seizures stopped just after sodium valproate medication. NCSE in patients with JME is rare but detailed history taking and suspicion of the disorder is helpful for diagnosis.

Status epilepticus (SE) in pregnancy is very rare, and there are only a few case reports of refractory SE (RSE) during pregnancy. The patient was a 27-year-old primigravida woman with a 21-year history of seizures from cortical dysplasia. At 23 weeks of pregnancy, the patient’s seizure frequency progressively increased, and the patient came to the ER in a confused mental state and with intermittent convulsive movements of her left arm. Electroencephalography (EEG) revealed repeated seizures. She was admitted to the ICU, and continuous EEG monitoring was done. Treatment was immediately started with various anti-SE medications, but her SE was not controlled. A cesarean section was done, and SE spontaneously stopped two weeks after the parturition. Parturition may be beneficial and the best treatment option in pregnant patients with RSE.

Ennola gives an example of a relation among the cyclotomic units which is not a combination of elementary relations. He also proves that twice any relation among the cyclotomic units is a consequence of elementary relations. In the sense of the distribution, the torsion part of the universal even punctured distribution $ \big(A_n ^0 \big)^+ $ is a 2-torsion group. In particular, when $n$ has three distinct prime divisors, $ \big(A_n ^0 \big)^+ $ has a unique 2-torsion element. The aim of this paper is to find an algorithm to produce the unique 2-torsion element when $n$ has three distinct odd prime divisors.

Neuromyelitis optica spectrum disorders (NMOSD) can cause various ocular motor disorders in addition to optic neuritis. Ocular motor findings associated with NMOSD include spontaneous vertical and gaze-evoked nystagmus, wall-eyed bilateral internuclear ophthalmoplegia, and trochlear nerve palsy. The association between dorsal midbrain syndrome and anti-aquaporin-4 antibody seropositivity has not been reported. Here, we report a patient displaying typical dorsal midbrain syndrome and anti-aquaporin-4 antibody seropositivity.