• Science of Emotion and Sensibility
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• v.18 no.1
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• pp.27-38
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• 2015

Vestibulo-ocular reflex (VOR) is a compensatory response of the extraocular muscles generated by vestibular signals to stabilize images on the retina during head/body movements. It has been reported that mismatches between retinal and vestibular information, which cause motion sickness or cybersickness, modify VOR. To investigate the characteristic changes of VOR in subjects experiencing cybersickness, we developed a low-cost, multi-purpose VOR measurement system using LabVIEW and Arduino. To test the applicability of the system, we performed two experiments. In Experiment 1, horizontal and vertical VORs of four participants were measured using a vestibular autorotation task. In Experiment 2, eight participants were exposed to a virtual navigation to measure changes of VORs as an index of cybersickness. We observed significantly greater head rotations and eye movements while the participants were exposed to the virtual navigation than to a static image. The results suggest that the present system can help understand the psychophysiological mechanisms of cybersickness symptoms.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1291-1299
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• 2001

Objectives : The authors present a retrospective analysis of 14 patients treated for spinal cord hemangioblastoma (SCH) between Dec. 1986 and Mar. 2000. This study was conducted to evaluate and compare the difference of the functional outcomes associated with the extent of surgical removal of SCH. Methods : Eleven patients were male and three patients were female. Their mean age was 37.2 years that ranged from 19 to 62 years. Preoperative magnetic resonance(MR) imaging of the spine was performed in all cases, and preoperative angiography in eleven cases. They were followed from 15 months to 161 months(median follow-up period, 47 months), and we investigated the change of neurological symptoms and functional outcomes with radiological features, especially on MR imaging. Results : Six patients were accompanied by von Hippel-Lindau disease, and three of them had multiple CNS tumors. Thirteen patients had intramedullary tumor, and the remaining one had extradural. Syringomyelia around the tumor was observed in ten cases. All patients underwent surgical removal, and gross total removal(GTR) was achieved in ten cases. Preoperative embolization was performed in four cases. In four patients who were treated with preoperative embolization, intraoperative loss of blood was minimal and GTR was possible. One patient developed a transient swallowing difficulty postoperatively without permanent postoperative neurological deficits. In three of four patients in whom GTR was not possible, their functional outcomes were worsened postoperatively. The functional status at discharge was improved in seven patients, stationary in four patients, and worse in three. At the last follow-up(15-161 months), one of four patients who had been stationary at discharge showed improvement but, the rest did not show any change. All patients who showed neurological improvement were patients with GTR, and the patients with GTR had significant better outcome than those without GTR(p=0.015). Conclusion : Surgical treatment, and especially, GTR is considered as treatment of choice for spinal cord hemangioblastoma. Preoperative embolization may prevent intraoperative bleeding and improve surgical outcome.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1308-1313
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• 2001

Object : The goals of radiosurgery include preservation of neurological function and prevention of tumor growth. We document the results of gamma-knife radio-surgery for vestibular schwannoma. Method & Object : Eighty-two patients underwent stereotactic radiosurgery for an vestibular schwannoma from October, 1994 to December, 2000. Sixty-five of these patients were followed up for radiological and clinical evaluation. As pregamma-knife modality, surgical resection were done in 23 patients,and V-P shunt in 2 patients. Initial symptoms were headache(n=45), dizziness(n=16), tinnitus(n=17). While normal facial function(House-Brackmann grade 1) was present in 48 patients(73.8%), other patients showed grade 2 function in 8, grade 3 function in 7,and grade 4 function in 2. The Gardner/Robertson scale was used to code hearing function. Male to female ratio was 1:3. Mean tumor volume was $7.98cm^3$. Mean dose delivered to the tumor margin was 14.2Gy,and mean maximal dose was 28.3Gy. Results : Mean follow-up duration of 19.9 months. Thirty-five showed decrease(53.8%) in size, 19 patients(29.2%) stationary, 3(4.6%) initial decrease follow up increase, 5(7.6%) initial increase follow up decrease,and 59 patients (90.8%) were well controlled. Two patients experienced transient facial neuropathy, one transient trigeminal neuropathy, and one transient hearing deterioration. After gamma-knife radiosurgery, ventriculoperitoneal shunt was done in 4 patients. Conclusions : Gamma-knife radiosurgery can be used to treat postoperative residual tumors as well as in patients with concomitant medical problems in patients with preserved hearing function. Gamma-knife radiosurgery is safe and effective method to treat small, medium sized(less than 3cm in extracanalicular diameter), intracanalicular vestibular schwannoma, associated with low rate of cranial neuropathy.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.24 no.4
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• pp.213-219
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• 2013

Objectives : It is known that adolescents with autism spectrum disorder (ASD) often concurrently exhibit attention-deficit hyperactivity disorder (ADHD). The objective of this study is to investigate how ADHD symptoms modify clinical characteristics in adolescents with ASD. Methods : Subjects were recruited from the Program for the Education Enrichment of Relational Skills program, which is a program for adolescents with ASD to promote and train social skills. The study participants and their parents completed the study questionnaires, such as the ADHD rating scale, Autism Diagnostic Observation Schedule, and Korean version of Child Behavior Checklist. Results : Adolescents with ASD and ADHD (N=19) were found to have more impaired sociality, less open communication with their parents, and more behavioral and emotional problems compared with adolescents with ASD, and without ADHD (N=28). Conclusion : Although further research is needed, the results of our study suggest that adolescents with ASD present different clinical characteristics when comorbid with ADHD.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.187-193
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• 2017

The Japanese pine sawyer, Monochamus alternatus Hope, is a representative vector of the pine wood nematode, Bursaphelenchus xylophilus, which causes wilting symptoms in pine trees. A control method using a net has been introduced, which is an alternative method to the fumigation for the control of dead pine trees by pine wilt disease. This study was carried out to investigate the factors that induce gnawing and escaping behaviors of M. alternatus. The behaviors were examined after M. alternatus adult was placed in a confined space at different temperatures. M. alternatus adults could escape through mesh net torn by gnawing when they were confined in a space of 30 mm or less in diameter. The success rate of escape was high at 20 to $30^{\circ}C$, and no adults escaped at $15^{\circ}C$. The enticement of M. alternatus adults by food didn't affect the success rate of escape. In the case of not being confined in a narrow space, the escaping hole could not be formed because the gnawing was not concentrated on one part. M. alternatus moved its body in a narrow space using the tarsus of middle and hind legs, and made an escape hole by concentrically gnawing the obstacle on the front side with mandible, and showed a behavior of getting out while supporting the body by supporting the front legs. The present results will be able to use as an important basic information for evaluating the performance of mesh net which confines M. alternatus adults and suggested by alternative method to fumigation technology.

• The Journal of Korean Academy of Prosthodontics
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• v.17 no.1
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• pp.7-21
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• 1979

This investigation was to analyse normal protrusive and lateral condylar pantographic records written on the sagittal plane and to study components of Fisher's angle and their interrelations. The purpose of this study was limited to (1) discussing the significance of sagittal pantographic record in diagnosis of occlusal disease and(2) basing for reasoning validity of measuring Fisher's angle which has been reported so far. As a result followings were concluded. 1. In each protrusive and lateral condylar movement path, five complicate factors such as initial straightness, distributed simple sigmoid type, simple curvature, initial tiny protruding convexity and tiny repeated sigmoid patterns were noted. Generally each condylar movement path was composed of two to three of these factors. 2. The distribution of positional interrelations of protrusive and lateral condylar paths could be divided into five categories; (a) protrusive-upper, (b) completely coinciding, (c) partially initial coinciding, (d) partially inverted crossing, and (e) completely inverting. Among these, protrusive path-upper positioned condyles were prevailed (79.2%). 3. The distribution of interrelations of protrusive and lateral condylar paths could be devided into five categories according to their distances in the course of movement. Among these, opening (95.8%) and paralleling (66.7%) were prevailing. 4. The involved number of characteristic heterogenous patterns of five categories in protrusive and lateral condylar movement recording relations at one simultaneous recordings was limited to three. However, in case of homogeneous patterns were repeated, usually three to four were included. 5. The maximum distance between protrusive and lateral condylar paths was 1.45mm at the location of 4mm advanced position from centric relation point and 3.90mm at the location of protrusive movement terminal. 6. It seemed to be that ,pantographic records should be consulted other clinical symptoms in order to make certain occlusion diagnosis. 7. At the present moment of investigation, expressing Fisher's angle as a degree revealed a lack due to inherent complexity of protrusive and lateral condylar movement paths. 8. The typical pattern of protrusive and lateral condylar paths written on a pantographic sagittal plate might be described as follows; (a) protrusive condylar path should be positioned upwardly, (b) both mainly be simple curvature, (c) interrelations mainly be opening or paralleling. 9. The mean amounts of separation between protrusive and lateral condylar movement path were $0.75{\pm}0.46$ at 4mm advanced location from centric relation and $1.74{\pm}0.64mm$ at the location of protrusive path terminal.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.4
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• pp.549-564
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• 1993

The purpose of this study was to research the condylar path and the anterior angle of glenoid fossae and classify the patterns of condylar path. Thirty male and female dental students with normal occlesion and masticatory system ranging in age from 21 to 30, without present symptoms and an)r history of TM joint disturbance, were selected for this study. Transcranial radiographs of TM joints under mandibular lateral movement were obtained. By the computer analysis on the radiographs, the angle of posterior slope of articular eminance, the sagittal condylar guidance angie, condylar movement patterns and the height of glenoid fossa was measured respectively, and studied their interrelationship comparatively. The results obtained were as follows : 1. The total distance of condylar movement on balancing side during mandibular lateral movement was 4.55mm for Lt. and 4.78mm for Rt. when mandible moved from C.R. to canine to canine relation and 7.86mm for the Lt. and 8.10mm for the Rt. when mandible moved from C.R. to 7.5mm. 2. The horizontal distance of condylar movement on balancing side during mandibular lateral movements was 3.16mm for the Lt. and 3.52mm for the Rt. when mandible moved from C.R. to canine to canine relation and 6.10mm for the Lt. and 6.30mm for the Rt. when mandible moved from C.R. to 7.5mm. 3. The sagittal condylar guidance angle on balancing side during mandibular lateral movements was $45.96^{\circ}$ for the Lt. and $43.22^{\circ}$ for the Rt. when mandible moved from C.R. from canine to canine relation and $41.14^{\circ}$ for the Lt. and $39.77^{\circ}$ for the Rt. when mandible moved from C.R. to 7.5mm. 4. The height of glenoid fossa was 8.23mm for the Lt. and 7.80mm for the Rt. and the angle of posterior slope of articular eminence was $38.30^{\circ}$ for the Lt. and $38.79^{\circ}$ for the Rt. by method-A and $55.61^{\circ}$ for the Lt. and $55.64^{\circ}$ for the Rt. by method-B. 5. The sequence of the frequency of condylar movement patterns on balancing side during mandibular lateral movement were concave type(30 cases), convex type(16 cases), reverse S shape curve(9 cases) and S shape curve(5 cases) when mandible moved from C.R. to canine to canine relation and concave type(27 cases), 5 shape curve(13 cases), convex type(11 cases) and reverse S shape curve(9 cases) when mandible moved from C.R. to 7.5mm.

• Korean journal of applied entomology
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• v.1
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• pp.3-10
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• 1962

1) The purpose of the present study is to investigate the effects of culture filtrates of Fusarium oxysporum f. vasinfectum which is known to produce fusaric acid (wilt toxin) on the germination of sesame seeds and the growth of sesame seedlings. 2) Culture filtrates of Fusarium oxysporum 1. vasinfectum used in this study strongly or weakly inhibited the germination and bring about necrosis accompanying black discoloration of sesame seeds. 3) Varietal difference of sesame in the germination response on the culture filtrates of Fnsarium oxysporum f. vasinfectum is not shown in this study. 4) This study reveals that differential five strains of Fnsarium oxysoprum f. vasinfectum used in this study differ greatly in the toxicity of culture filtrates inhibiting the germination of sesame seeds. 5) In the seedling bed added with culture filtrates of Fnsarium oxysporum f. vasinfectum, the growth of shoot as well as root system of sesame seedlings are notably inhibited and necrotic black discoloration appear on both shoot and root system. But in the seedling beds added with weaker concentration of culture filtrates $/(10\%)$ the growth of shoot is slightly promoted. 6) In culture of sesame seedlings with Knop's solution containing 1 to 3 per cent culture filtrates, the growth of shoot as well as root system are slightly retarded" and till the time of development of the third leaves the whole stem and leaf petiole tissue are weakened so that they become thread like accompanying brown discoloration, interveinal light brown area appear in the second leaves, and the third leaves curl from both sides towards the middle with necrotic brown discoloration, especially symptoms of injury on the third leaves are nearly similar that of the leaves of wilted sesame in the field. 7) A pararell relationship is not found between toxicity of culture filtrates and pathogenicity of five differential strains of Fnsarium oxysporum f. vasinfectum used in this study.

• Genomics & Informatics
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• v.10 no.2
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• pp.110-116
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• 2012

Recent several studies have shown that the genetic variation of SCN5A is related with atrioventricular conduction block (AVB); no study has yet been published in Koreans. Therefore, to determine the AVB-associated genetic variation in Korean patients, we investigated the genetic variation of SCN5A in Korean patients with AVB and compared with normal control subjects. We enrolled 113 patients with AVB and 80 normal controls with no cardiac symptoms. DNA was isolated from the peripheral blood, and all exons (exon 2-exon 28) except the untranslated region and exon-intron boundaries of the SCN5A gene were amplified by multiplex PCR and directly sequenced using an ABI PRISM 3100 Genetic Analyzer. When a variation was discovered in genomic DNA from AVB patients, we confirmed whether the same variation existed in the control genomic DNA. In the present study, a total of 7 genetic variations were detected in 113 AVB patients. Of the 7 variations, 5 (G87A-A29A, intervening sequence 9-3C>A, A1673G-H558R, G3578A-R1193Q, and T5457C-D1819D) have been reported in previous studies, and 2 (C48G-F16L and G3048A-T1016T) were novel variations that have not been reported. The 2 newly discovered variations were not found in the 80 normal controls. In addition, G298S, G514C, P1008S, G1406R, and D1595N, identified in other ethnic populations, were not detected in this study. We found 2 novel genetic variations in the SCN5A gene in Korean patients with AVB. However, further functional study might be needed.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.270-274
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• 2009

Dentigerous cysts generally encompass the crown of an unerupted tooth. These cysts are usually solitary. They are the second most common odontogenic type of cysts following radicular cysts, and are frequently associated with impacted mandibular third molars or maxillary canines. Most multiple cysts found in the jaw are odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome, mucopolysaccharidoses and cleidocranial dysplasia. Although a single dentigerous cyst is well documented in the medical literature, including the prevalence, treatment and prognosis, multiple dentigerous cysts without any systemic symptoms is unusual. Furthermore, cases involving both the maxilla and mandible are especially rare. We present the case of an 11-year-old boy with nonsyndromic multiple dentigerous cysts associated with a mandibular second premolar and a maxillary canine. The treatment was conservative and included marsupialization and eruption guidance. Further follow up is planned to rule out additional problems and the possible identification of a syndrome.