• Journal of Astronomy and Space Sciences
• /
• v.24 no.2
• /
• pp.125-134
• /
• 2007

In this paper, we analyze the orbital variation of the Korea Multi-Purpose SATellite-1(KOMPSAT-1) in a strong space environment due to satellite drag by solar and geomagnetic activities. The satellite drag usually occurs slowly, but becomes serious satellite drag when the space environment suddenly changes via strong solar activity like a big flare eruption or coronal mass ejections(CMEs). Especially, KOMPSAT-1 as a low earth orbit satellite has a distinct increase of the drag acceleration by the variations of atmospheric friction. We consider factors of solar activity to have serious effects on the satellite drag from two points of view. One is an effect of high energy radiation when the flare occurs in the Sun. This radiation heats and expands the upper atmosphere of the Earth as the number of neutral particles is suddenly increased. The other is an effect of Joule and precipitating particle heating caused by current of plasma and precipitation of particles during geomagnetic storms by CMEs. It also affects the density of neutral particles by heating the upper atmo-sphere. We investigate the satellite drag acceleration associated with the two factors for five events selected based on solar and geomagnetic data from 2001 to 2002. The major results can be summarized as follows. First, the drag acceleration started to increase with solar EUV radiation with the best cross-correlation (r = 0.92) for 1 day delayed F10.7. Second, the drag acceleration and Dst index have similar patterns when the geomagnetic storm is dominant and the drag acceleration abruptly increases during the strong geomagnetic storm. Third, the background variation of the drag accelerations is governed by the solar radiation, while their short term (less than a day) variations is governed by geomagnetic storms.

• Korean Journal of Psychosomatic Medicine
• /
• v.13 no.1
• /
• pp.3-15
• /
• 2005

Objectives The author aimed to investigate and understand the limitations of the biopsychosocial model for irritable bowel syndrome by reviewing the priorly reported etiologies in patients with irritable bowel syndrome(IBS). Methods The author reviewed all possible previous studies related to the investigation regarding IBS in the Pub-med & Kisep database from 1977 to 2003. Results : It was impossible that patients with IBS were diagnosed and traced to a single etiology. So, the biopsychosocial model was suggested to be a new paradigm for IBS. Biological, psychological and social factors are interplaying and contributing to the biopsychosocial model affecting each other, thus affecting the biopsychosocial model. Three factors were necessary for understanding the etiology, process of symptoms and clinical outcome of IBS by virtue of their key roles in the developing, precipitating and perpetuating of the illness. However, any treatment application for those three factors faces many obstacles to be overcome. Conclusion : The biopsychosocial model contributed relatively much to the explanation but little to the treatment application of patients with IBS. Therefore, because there seems to be little practical use at present, the author believes biopsychosocial aspects should be researched further.

• Journal of Korean society of Dental Hygiene
• /
• v.17 no.3
• /
• pp.465-478
• /
• 2017

Objectives: The purpose of this study was to investigate the relationship between the level of subjective stress recognition and oral symptom experiences including toothache, gum diseases, and oral soft tissue diseases in the Korean adolescents. Methods: The subjects were 68,043 adolescents recruited using a web-based survey, National Korean Youth Risk Behavior in 2015 by the Korean Center for Disease Control. For statistical analysis, SPSS 21.0 for Windows was used. Descriptive analysis and a Chi-square test were conducted to determine the factors associated with general characteristics, health behaviors, oral health behaviors, and level of subjective stress recognition. Finally, to investigate the relationship between the level of subjective stress recognition and oral symptom experiences, logistic regression analysis was performed. Results: Toothache related subjective stress recognition level was significantly higher in the moderate group with the score of 1.59 (95% CI; 1.49-1.68), and was greater in the high group with 2.38 (95% CI; 2.24-2.53) compared to the low group. Gum disease related subjective stress recognition level was significantly higher in the moderate group with 1.41 (95% CI; 1.32-1.51), and was greater in the high group with 1.99 (95% CI; 1.86-2.13). Oral soft tissue disease related subjective stress recognition level was significantly higher in the moderate group with 1.59 (95% CI; 1.45-1.74), and was greater in the high group with 2.55 (95% CI; 2.33-2.79). Bad breath related subjective stress recognition level was significantly higher in the moderate group with 1.48 (95% CI; 1.39-1.57), and was greater in the high group with 2.10 (95% CI; 1.97-2.25). Conclusions: Higher subjective stress recognition level was found to affect the oral symptoms experienced. Therefore, the stress management plan should be prepared through the cause identification of the main stress in the adolescents. Practical and systematic education is needed for oral health management in the schools.

• Korean small business review
• /
• v.42 no.3
• /
• pp.275-304
• /
• 2020

The purpose of this study is to present implications for revitalizing start-ups and contribute to enhancing the success rate of start-ups by clarifying factors and processes for converting workers with knowledge, experience and networks in related fields into entrepreneur. Based on the Shapero's Entrepreneurial Event Model, this study demonstrated whether the job insecurity and entrepreneurship of the workers were precipitating events of the entrepreneurial intention and whether the perceived desirability and feasibility of the entrepreneurial behaviour mediated between them. According to the results of the study, first, it was confirmed that job insecurity, innovativeness, and risk-taking of workers are factors that increase the entrepreneurial intention. Second, the indirect effect of perceived desirability between all components of job insecurity and entrepreneurial intentions was not significant, but all components of entrepreneurship appeared to improve entrepreneurial intention through perceived desirability. Third, it has been confirmed that job insecurity, innovativeness, and risk-taking strengthen the entrepreneurial intention through the perception of feasibility for entrepreneurial behavior. Through this study, it is confirmed that in order to convert workers into entrepreneur, it is necessary to strengthen entrepreneurship education and support for internal ventures for workers to increase their positive attitude and confidence in implementation. Therefore, it is expected to help solve job problems and revive the sluggish economy by contributing to boosting start-ups.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.12 no.1
• /
• pp.103-114
• /
• 2001

Tourette's disorder is a disease which manifests one or more motor tics and vocal tics for more than a year. Chronic motor tic or vocal tic disorders are characterized by only one kind of tics for more than a year. We intended to investigate the clinical characteristics of the patients with chronic motor tic disorders or Tourette's disorders who had admitted from May 1, 1998 to May 1, 1999 to Seoul National University Hospital Child and Adolescent Psychiatry ward. In addition, we compared the clinical characteristics of the patients in order to elucidate the relationship between the two disorders. The patients with learning disabilities were selected as controls. There was no statistically significant difference between the onsets of the patients with chronic motor tic disorders(n=13, $7.3{\pm}2.5$ years), and Tourette's disorder(n=39, $7.2{\pm}2.2$ years), but with learning disability($4.2{\pm}1.9$ years). Also, the patients with chronic motor tic disorder and Tourette's disorder showed similar age at admission($11.7{\pm}2.7$ versus $11.5{\pm}2.6$ years), duration of admission($5.7{\pm}5.4$ versus $11.0{\pm}8.7$ weeks), mothers' ages at child birth($27.3{\pm}2.9$ versus $28.3{\pm}6.7$ years old),and fathers' age at child birth($32.2{\pm}3.2$ versus $33.3{\pm}5.2$ years old). We observed that those who had learning disabilities were alike in those aspects, except for age at visit to clinic($9.8{\pm}3.2$ years old). Family history of psychiatric illnesses(24.1% versus 46.2%), recognized precipitating factors(11.1% versus 35.7%) and response to pharmacological treatments(77.8% versus 76.9%) of the patients with chronic motor tic disorders and Tourette's disorders were observed and no differences were found. Comorbid patterns of diseases were noted. Intrafamilial conflicts were more common in the patients with learning disabilities than those with chronic tic disorders or Tourette's disorders. Precipitating factors were observed more frequent in chronic tic disorder and Tourette's disorder than learning disability. Neurocognitive profiles were investigated, and verbal IQs of the patients with chronic motor tic disorder, Tourette's disorder and learning disability were $92.3{\pm}10.7$, $94.7{\pm}14.9$, $94.3{\pm}13.8$, performance IQs $93.0{\pm}20.5$, $97.5{\pm}13.0$, $95.0{\pm}16.9$ and full-scale IQs $91.9{\pm}20.1$, $95.8{\pm}14.5$, $93.9{\pm}15.1$, respectively, which were found to be not significantly different. No difference was found in structural neurological abnormalities and EEG profiles. The patients with learning disabilities showed more common Bender-Gestalt test abnormalities. In conclusion, we have not found any affirmative clues for the division of chronic motor tic disorder and Tourette's disorder in clinical perspective.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.7 no.1
• /
• pp.68-76
• /
• 1996

30 DSM-III or DSM-III-R tic patients were assessed by hospital records and Yale Global Tic Severity Scale to study the common characteristics, clinical course and longterm outcome of tic disorders after 3.1-18.1 years, 73.3% of the patients(treated or untreated) have recovered or partially improved. Identifical precipitating factors were found in 9 patients. Associated disorders were ADHD, sleep disorder, and so on. The outcome according to age of onset, duration of follow-up and diagnoses have no statistically significance. Increased age at follow up was influenced improvement of tic symptoms, though statistically not significant(p=0.327). These results suggest that the outcome of tic disorder is not ominous and they are relatively good social adjustment inspite of carrying the tic symptoms. But this study has some limitations such as retrospective study and sample size. Studies designed prospectively with large sample would be needed to generalize theses results.

• Radiation Oncology Journal
• /
• v.24 no.4
• /
• pp.317-321
• /
• 2006

A case is reported of a man with malignant fibrous histiocytoma (MFH) in right thigh who developed streptococcal toxic shock syndrome (STSS) during postoperative radiotherapy. Before radiotherapy, a patient complained wax and wane lymphedema following wide excision of tumor mass which was confirmed as MFH. He took some nonsteroidal antiinflammatory drug (NSAID) for about one month. He suffered preexisting hepatitis C virus (HCV) infection, diabetes and well-controlled hypertension. The patient received conventional radiotherapy to right thigh with a total dose of 32.4 Gy at 1.8 Gy per day. At last radiotherapy fraction, cutaneous erythematous inflammation was suddenly developed at his affected thigh. At that time, he also complained of oliguria, fever and chills. The patient was consulted to internal medicine for adequate evaluation and management. The patient was diagnosed as suggested septic shock and admitted without delay. At admission, he showed hypotension, oliguria, constipation, abnormal renal and liver function. As a result of blood culture, Streptococcus pyogenes was detected. The patient was diagnosed to STSS. He was treated with adequate intravenous antibiotics and fluid support. STSS is one of oncologic emergencies and requires immediate medical intervention to prevent loss of life. In this patient, underlying HCV infection, postoperative lymphedema, prolonged NSAID medication, and radiotherapy may have been multiple precipitating factors of STSS.

• Clinical and Experimental Pediatrics
• /
• v.51 no.7
• /
• pp.771-774
• /
• 2008

Familial hypokalemic periodic paralysis (hypoPP) is a rare inherited channelopathy that often presents with episodic weakness accompanied by hypokalemia. Thus far, mutations in the gene encoding two ion channels (CACNL1A3, L-type calcium channel alpha-1 subunit and SCN4A, a sodium channel type IV alpha subunit) have been identified. Several cases of familial hypoPP in children have been reported in Koreans, but there are only a few cases with identified mutations. We report a 12-year-old boy and his affected mother with hypoPP who has a heterozygous G to A substitution at codon 1239 in exon 30 of the CACNL1A3 gene that causes a change from arginine to histidine (Arg1239His, CACNL1A3). This mutation is common among Caucasians; however, it has not yet been reported in Koreans. The patients were treated with oral acetazolamide and potassium replacement and were instructed to avoid precipitating factors. After the medication and lifestyle modification, the paralytic attacks significantly decreased.

• Journal of Yeungnam Medical Science
• /
• v.5 no.2
• /
• pp.151-160
• /
• 1988

To evaluate the features of pyuria related to the bacteriuria, 140 subjects were studied from Jan. 1987 to Dec. 1987. The pyuria was frequently developed from the age 30 to 60 years old, and male to female ratio was 1:1.41. The most common disease was urethrocystitis that was shown 42.8%. Common precipitating factors were urethral catheterization(25%) and urinary tract obstruction(11.4 %). Through the observation, symptomatic pyuric patients were 66 subjects(47.1%), and the subjects with significant urine culture were 121 subjects(86.4%). In the urine culture, the most common bacteria was E. coli(41.4%), and the next was Pseudomonas(19.3%). A large percentage of E. coli and Pseudomonas was susceptible of amikin. The pyuria due to S. epidermidis and Accinatobacter was well treated. High therapeutic rate was observed in the acute pyelonephritis(71%) and urethrocystitis(67%). In the persistent urinary tract infection, there were relapsing(22 cases) and recurrent urinary tract infection(16 cases).

• Journal of Korean Neurosurgical Society
• /
• v.63 no.5
• /
• pp.607-613
• /
• 2020

Objective : Spontaneous intracranial hemorrhage is a life-threatening disease, and non-lesional spontaneous intraparenchymal hemorrhage (nIPH) and aneurysmal subarachnoid hemorrhage (aSAH) are the leading causes of spontaneous intracranial hemorrhage. Only a few studies have assessed the association between prior physical activity or triggering events and the occurrence of nIPH or aSAH. The purpose of this study is to investigate the role of specific physical activities and triggering events in the occurrence of nIPH and aSAH. Methods : We retrospectively reviewed 824 consecutive patients with spontaneous intracranial hemorrhage between January 2010 and December 2018. Among the 824 patients, 132 patients were excluded due to insufficient clinical data and other etiologies of spontaneous intracranial hemorrhage. The medical records of 692 patients were reviewed, and the following parameters were assessed : age, sex, history of hypertension, smoking, history of stroke, use of antiplatelet or anticoagulation agents, season and time of onset, physical activities performed according to the metabolic equivalents, and triggering event at onset. Events that suddenly raised the blood pressure such as sudden postural changes, defecation or urination, sexual intercourse, unexpected emotional stress, sauna bath, and medical examination were defined as triggering events. These clinical data were compared between the nIPH and aSAH groups. Results : Both nIPH and aSAH most commonly occurred during non-strenuous physical activity, and there was no significant difference between the two groups (p=0.524). Thirty-two patients (6.6%) in the nIPH group and 39 patients (8.1%) in the aSAH group experienced triggering events at onset, and there was a significant difference between the two groups (p=0.034). The most common triggering events were defecation or urination in both groups. Conclusion : Specific physical activity dose no affect the incidence of nIPH and aSAH. The relationship between the occurrence of intracranial hemorrhage and triggering events is higher in aSAH than nIPH.