• Journal of Korea Game Society
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• v.4 no.4
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• pp.11-18
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• 2004

The on-line games in the past were played by only two persons exchanging data based on one-to-one connections, whereas recent ones (e.g. MMORPG: Massively Multi-player Online Role-playings Game) enable tens of thousands of people to be connected simultaneously. Specifically, Korea has established an excellent network infrastructure that can't be found anywhere in the world. Almost every household has a high-speed Internet access. What made this possible was, in part, high density of population that has accelerated the formation of good Internet infrastructure. However, this rapid increase in the use of on-line games may lead to surging traffics exceeding the limited Internet communication capacity so that the connection to the games is unstable or the server fails. expanding the servers though this measure is very costly could solve this problem. To deal with this problem, the present study proposes the load distribution technology that connects in the form of local clustering the game servers divided by their contents used in each on-line game reduces the loads of specific servers using the load balancer, and enhances performance of sewer for their efficient operation. In this paper, a cluster system is proposed where each Game server in the system has different contents service and loads are distributed efficiently using the game server resource information such as CPU utilization. Game sewers having different contents are mutually connected and managed with a network file system to maintain information consistency required to support resource information updates, deletions, and additions. Simulation studies show that our method performs better than other traditional methods. In terms of response time, our method shows shorter latency than RR (Round Robin) and LC (Least Connection) by about 12%, 10% respectively.

• Clinical and Experimental Pediatrics
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• v.45 no.2
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• pp.183-191
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• 2002

Purpose : X-linked agammaglobulinemia(XLA) is an immunodeficiency caused by abnormalities in Bruton's tyrosine kinase(Btk), and is characterized by a deficiency of peripheral blood B cells. We studied the cytoplasmic expression of Btk protein and analyzed the Btk gene in peripheral blood mononuclear cells from two siblings and one cousin with XLA, as well as additional family members. Methods : Btk protein expression was analyzed by flow cytometry. Isolation of the coding sequence of the Btk gene was performed by amplification using the reverse transcription-polymerase chain reaction(RT-PCR) technique. Sequence alterations were screened by the single-stranded conformation polymorphism(SSCP) method and characterized by standard sequencing protocols. Results : Cytoplasmic expression of Btk protein in monocytes was not detected in three patients with XLA. In addition, Btk protein analysis clearly showed cellular mosaicism in monocytes from four obligate carriers, findings further supported by SSCP. A single base pair mutation(T to C) in Btk-exon three, which encodes the PH domain, was identified in four XLA patients. A diagnostic sequencing analysis was established to detect heterozygotic pattern in 4 carrier females. Furthermore, we found significant clinical heterogeneity in individuals with the same gene mutation. Conclusion : The implicating genetic alteration provided valuable clues to the pathogenesis of XLA in Korea and the flow cytometric analysis was suggested as a useful tool for rapid detection of XLA patients and carriers. The present study has identified a genetic mutation in the Btk coding region and demonstrated heterogeneity in clinical manifestations among patients with the same mutation. A flow cytometric analysis was found to be informative in establishing a deficiency of Btk protein in both patients and carriers and is recommended as a frontline procedure in the molecular diagnosis and work-up of XLA.

• Journal of Life Science
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• v.22 no.11
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• pp.1456-1462
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• 2012

Sorafenib is a multikinase inhibitor and an oral anticancer drug approved for the treatment of patients with advanced renal cell carcinoma and those with unresectable hepatocellular carcinoma. The purpose of this study was to develop an efficient method of the determination of sorafenib in human plasma using tandem mass spectrometry coupled with liquid chromatography (LC/MS/MS) and validate the method by the guidelines of the Korean Food and Drug Administration (KFDA). Plasma samples ($100{\mu}l$) were added with chlorantraniliprole as an internal standard and then mixed with the 0.1% formic acid-containing extraction solution composed of isopropyl alcohol and ethyl acetate (1:4, v/v). After centrifugation, the supernatant was concentrated at $45^{\circ}C$ under negative pressure and centrifugal force. The residue was reconstituted with a mobile phase and injected into the HPLC instrument using a reverse phase Waters XTerra$^{TM}$ C18 column (particle size $3.5{\mu}m$). Liquid chromatography was carried out within the run time of 5 min using a mobile phase composed of buffer (0.1% formic acid and 10 mM ammonium formate), methanol, and acetonitrile (1:6:3, v/v/v). The analytes were monitored by tandem mass spectrometry in the multiple reaction monitoring method programmed to detect sorafenib at 'm/z 465.2 ${\rightarrow}$ 252.5' and chlorantraniliprole at 'm/z 484.4 ${\rightarrow}$ 286.2' with positive electrospray ionization mode ($ES^+$). The result showed the proper linearity ($r^2$ > 0.99) over the range of 2,000-5,000 ng/ml with good accuracy (90.7-103.9%) and precision (less than 10%). The newly developed method using LC/MS/MS was validated by the guideline of KFDA and identified as more sensitive compared to the previous methods.

• Progress in Medical Physics
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• v.23 no.4
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• pp.309-316
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• 2012

Multimodal-imaging technique has been rapidly developed for improvement of diagnosis and evaluation of therapeutic effects. In despite of integrated hardware, registration accuracy was decreased due to a discrepancy between multimodal image and insufficiency of count in accordance with different acquisition method of each modality. The purpose of this study was to improve the PET image by event data resampling through analysis of data format, noise and statistical properties of small animal PET list data. Inveon PET listmode data was acquired as static data for 10 min after 60 min of 37 MBq/0.1 ml $^{18}F$-FDG injection via tail vein. Listmode data format was consist of packet containing 48 bit in which divided 8 bit header and 40 bit payload space. Realigned sinogram was generated from resampled event data of original listmode by using adjustment of LOR location, simple event magnification and nonparametric bootstrap. Sinogram was reconstructed for imaging using OSEM 2D algorithm with 16 subset and 4 iterations. Prompt coincidence was 13,940,707 count measured from PET data header and 13,936,687 count measured from analysis of list-event data. In simple event magnification of PET data, maximum was improved from 1.336 to 1.743, but noise was also increased. Resampling efficiency of PET data was assessed from de-noised and improved image by shift operation of payload value of sequential packet. Bootstrap resampling technique provides the PET image which noise and statistical properties was improved. List-event data resampling method would be aid to improve registration accuracy and early diagnosis efficiency.

• Journal of Chest Surgery
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• v.37 no.1
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• pp.27-34
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• 2004

Background: Infective endocarditis shows higher operative morbidity and mortality rates than other cardiac diseases. The vast majority of studies on infective endocarditis have been made on aortic endocarditis, with little attention having been paid to infective endocarditis on the mitral valve. This study attempts to investigate the clinical aspects and operative results of infective endocarditis on the mitral valve. Meterial and Method: The subjects of this study consist of 23 patients who underwent operations for infective endocariditis on the mitral valve from June 1995 to May 2003. Among them, 2 patients suffered from prosthetic valvular endocarditis and the other 21 from native valvular endocarditis. The subjects were evenly distributed age-wise with an average age of 44.8$\pm$15.7 (11∼66) years. Emergency operations were performed on seventeen patients (73.9%) due to large vegetation or instable hemodynamic status. In preoperative examinations, twelve patients exhibited congestive heart failure, four patients renal failure, two patients spleen and renal infarction, and two patients temporary neurological defects, while one patient had a brain abscess. Based on the NYHA functional classification, seven patients were determined to be at Grade II, 9 patients at Grade III, and 6 patients at Grade IV. Vegetations were detected in 20 patients while mitral regurgitation was dominant in 19 patients with 4 patients showing up as mitral stenosis dominant on the preoperative echocardiogram. Blood cultures for causative organisms were performed on all patients, and positive results were obtained from ten patients, with five cases of Streptococcus viridance, two cases of methicillin-sensitive Staphylococcus aureus, and one case each of Corynebacteriurn, Haemophillis, and Gernella. Operations were decided according to the AA/AHA guidelines (1988). The mean follow-up period was 27.6 $\pm$23.3 (1 ∼ 97) months. Result: Mitral valve replacements were performed on 43 patients, with mechanical valves being used on 9 patients and tissue valves on the other 4. Several kinds of mitral valve repair or mitral valvuloplasty were carried out on the remaining 10 patients. Associated procedures included six aortic valve replacements, two tricuspid annuloplasty, one modified Maze operation, and one direct closure of a ventricular septal defect. Postoperative complications included two cases of bleeding and one case each of mediastinitis, low cardiac output syndrome, and pneumonia. There were no cases of early deaths, or death within 30 days following the operation. No patient died in the hospital or experienced valve related complications. One patient, however, underwent mitral valvuloplasty 3 months after the operation. Another patient died from intra-cranial hemorrhage in the 31st month after the operation. Therefore, the valve-related death rate was 4.3%, and the valve-related complication rate 8.6% on mid-term follow-up. 1, 3-, and 5-year valve- related event free rates were 90.8%, 79.5%, and 79.5%, respectively, while 1, follow-up. 1, 3-, and 5-year valve- related event free rates were 90.8%, 79.5%, and 79.5%, respectively, while 1, 3-, and 5-year survival rates were 100%, 88.8%, and 88.8%, respectively. Conclusion: The findings suggest that a complete removal of infected tissues is essential in the operative treatment of infectious endocarditis of the mitral valve. It is also suggested that when infected tissues are completely removed, neither type of material nor method of operation has a significant effect on the operation result. The postoperative results also suggest the need for a close follow-up observation of the patients suspected of having brain damage, which is caused by preoperative blood contamination or emboli from vegetation, for a possible cerebral vascular injury such as mycotic aneurysm.

• Journal of Hospice and Palliative Care
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• v.13 no.1
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• pp.13-23
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• 2010

Purpose: This study was to identify the role of general hospice palliative nurse through job analysis (duties, task, and task elements). Methods: The sample consisted of 136 nurses or professors who were performing duties related to hospice care areas in Korea. A survey method was used, and the questionnaire included frequencies, criticality, and difficulties of task elements in job description by the DACUM method. Descriptive statistics were performed by using SPSS WIN 17.0. Results: The job description of general hospice palliative nurse was identified 8 duties, 36 tasks, and 137 task elements. As for the 8 duties, the average scores of frequency, criticality, and difficulty were 2.94, 3.66, and 2.80, respectively. The role of ‘pain assessment’ was the most important task element among frequency and criticality. The lowest score at the frequency and criticality were ‘manage public finance’ and ‘collect datum through diagnostic test & lab', respectively. Furthermore, the role of 'identify spiritual needs of patients and family' was the most difficult task, whereas the role of 'manage documents and information' was the least. Conclusion: In this study, we could recognize the reality of general hospice palliative nurse's performances. For general hospice palliative nurse, therefore, concrete practice guide lines of psychosocial and spiritual care, communication skills, and bereavement care with qualifying system are critically needed.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.1
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• pp.193-203
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• 2013

The social welfare service is expanding to different field as the social welfare budget is increasing. By this opportunity, it needs to make clear of the basis of argument that the necessity of development of korean government's support and aid by social policy should be worked. Welfare economics perspective, this study used by the operating expenditure in welfare facilities for the elderly old people to effect social benefits to be gained, in other words, business value analysis. Local elderly people, provide opportunities to participate in the economic activities of the family welfare services offered to attainment of the elderly welfare policy, and provide disease prevention and health promotion opportunities, to enhance the satisfaction of life, including a wide range of impact will cause. In this study, elderly people use the welfare facilities for the elderly when they get the benefits by applying the AHP analysis techniques operating value was calculated. Elderly Welfare Center operated by the result of applying P senior welfare center Case of the metropolitan area value was estimated 248.4 billion won. Contribute to the effects caused by the cost factor of the analysis was 23.1% of the total 57.3 billion won. Independence elements 57.6 billion (23.2%), the analysis of the therapeutic elements 133.4 billion (53.7%) of the net was. The result of the study anticipates the role of basic research material for the necessity of intervention, support, and aid by the Welfare facilities for the elderly field at this point in time where the welfare budget policy in terms of universal social service is reinforced, rather than the trend, until recently, of realizing the Elderly welfare budget and service as Consumption expenditure and consumable benefits and the function of performing the effect and evaluation in tentative action of social conflict.

• Applied Microscopy
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• v.39 no.2
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• pp.133-139
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• 2009

A officinal mushroom, Phellinus linteus (PL) has been known to exhibit potent biological activities including antioxidative and anticancer effect. PL is consumed as a type of powder or extract for the purpose of health promotion and disease treatment. Recently superfine PL products was commercialized according to the development of pulverizing technology such as nanomill, so the evaluation of food safety is suggested. This study was conducted to evaluate the food safety of superfine PL (SPL) through hematological, biochemical and histological examination in mice as compared with fine PL (FPL). In the particle size distribution in volume after nanomill processing, the mean diameter of SPL and FPL particles was 11.78 ${\mu}m$ and 216.1 ${\mu}m$, and d (0.5), the particle diameter measured at 50% of distribution was 5.5 ${\mu}m$ and 147.9 ${\mu}m$, respectively. As the result of body weight, food intake and the weight of organs, SPL group didn't show any statistical difference compared with FPL group and normal group (N). Hematological and biochemical values were also involved in the normal range, although ALT (N vs. FPL, P<0.001) and BUN (N vs. FPL, P<0.01; N vs. SPL, P<0.01) showed significance compared with N group but there are no significance between FPL and SPL group. In the result of histological examination with liver, kidney, spleen, and small and large intestine, abnormal findings such as inflammatory reaction and histological changes were not observed. Our results suggest that the oral intake of SPL diet is not harmful to the animal in the hematological, biochemical and histological aspects although particle size was reduced to the level of superfine. However, further study will be necessary to confirm the histological safety in relation to the gastrointestinal contact of superfine particles in the case of large amount and long-term intake.

• Journal of Life Science
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• v.24 no.5
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• pp.567-572
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• 2014

Extracts of Platycodon grandiflorum have been reported to show anti-inflammatory, antioxidant, anti-metastatic, and hepato-protective effects. This study was designed to evaluate T-cell activation and M1/M2 differential macrophage activation by extracts of P. grandiflorum or P. grandiflorum containing various medicinal herbs. Using real-time RT-PCR, we analyzed expression levels of c-fos, and CD40L (T-cell activation markers) in splenocytes and iNOS, Ym1, and ARG1 in RAW 246.7 cells after treatment of CC (hot water extract of P. grandiflorum), MAEK (hot water extract of P. grandiflorum [82%] and six different plants), and HWAL (hot water extract of P. grandiflorum [7%] and eight different plants. The results showed that MAEK significantly elevated the expression of T-cell activation markers of splenocytes, with the c-fos gene activated more than 10-fold and the CD40L gene activated more than 6-fold. Although CD40L was significantly increased by CC and HWAL, the increase was only about 2-fold. In addition, CC and HWAL did not significantly activate the expression of the c-fos gene. On the other hand, CC elevated the M1 activation marker iNOS, and HWAL elevated the M2 activation marker Ym1 and ARG1 gene expression. In conclusion, MAEK could be used as an immune stimulant because of its ability to activate T cells (elicited c-fos and CD40L gene expression), whereas HWAL could serve as an anti-inflammatory agent because of its differential activation of M2 macrophages.

• Journal of Chest Surgery
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• v.34 no.11
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• pp.831-842
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• 2001

Background: Patients with cardiac diseases who have structural defects in their heart bring about metabolic insult such as preoperative acid-base imbalance. Cardiac operation requires many nonphysiologic procedures such as extracorporeal circulation, hypothermia, and hemodilution. We studied the acid-base status of surgical heart diseases pre-operatively, during extracorporeal circulation, and post-operatively and researched the treatment indications of acid-base disturbances. Material and Method: From January 1997 to May 1999, fifty two cases of open heart surgery were carried out under extracorporeal circulation, which divided into a set of pediatric and adult groups, congenital and acquired groups, non-cyanotic and cyanotic groups, The $\alpha$ -stat arterial blood gas analysis was done in each group during the preoperative period, during the operation with extracorporeal circulation, and during the postoperative period. Result: Before surgery, all patients present metabolic acidosis, PaO2 was low in adult group and acquired group and compensatory respiratory alkalosis was noted in cyanotic group. During extracorporeal circulation, adult group revealed alkalosis and normal in acquired group. Pediatric group presents low Pa$CO_2$, metabolic acidosis and respiratory alkalosis. Congenital group and non-cyanotic group showed non-compensatory alkalosis trend and non-compensatory respiratory acidosis were observed in cyanotic group during extracorporeal circulation. Postoperative acid-base status of adult group was recovered to normal and the standard bicarbonate was increased in the acquired group. All of the pediatric, congenital non-cyanotic, and cyanotic groups revealed the lack of buffer base.