• Journal of Chest Surgery
• /
• v.41 no.4
• /
• pp.405-416
• /
• 2008

Background: Spinal cord ischemic injury during thoracic and thoracoabdominal aortic surgeries remains a potentially devastating outcome despite using various methods of protection. Neuronal voltage-dependent sodium channel antagonists are known to provide neuroprotection in cerebral ischemic models. This study was designed to compare the neuroprotective effects of phenytoin with those of hypothermia in a rabbit model of spinal cord ischemia. Material and Method: Spinal cord ischemia was induced in New Zealand white rabbits by means of infrarenal aortic cross clamping for 25 minutes. Four groups of 8 animals each were studied. The control group and the hypothermia group received retrograde infusion of saline only ($22^{\circ}C$, 2 mL/min); the normothermic phenytoin group and the hypothermicphenytoin group received retrograde infusion of 100 mg of phenytoin at different rectal temperatures ($39^{\circ}C$ and $37^{\circ}C$, respectively) during the ischemic period. The neurologic function was assessed at 24 and 72 hours after the operation with using the modified Tarlov criteria. The spinal cords were harvested after the final neurologic examination for histopathological examination to objectively quantify the amount of neuronal damage. Result: No major adverse effects were observed with the retrograde phenytoin infusion during the aortic ischemic period. All the control rabbits became severely paraplegic, Both the phenytoin group and the hypothermia group had a better neurological status than did the control group (p < 0.05). The typical morphological changes that are characteristic of neuronal necrosis in the gray matter of the control animals were demonstrated by means of the histopathological examination, whereas phenytoin or hypothermia prevented or attenuated these necrotic phenomena (p < 0.05). The number of motor neuron cells positive for TUNEL staining was significantly reduced, to a similar extent, in the rabbits treated with phenytoin or hypothermia. Phenytoin and hypothermia had some additive neuroprotective effect, but there was no statistical significance between the two on the neurological and histopathological analysis. Conclusion: The neurological and histopathological analysis consistently demonstrated that both phenytoin and hypothermia may afford significant spinal cord protection to a similar extent during spinal cord ischemia in rabbits, although no significant additive effects were noticed.

• Journal of Distribution Science
• /
• v.9 no.1
• /
• pp.39-48
• /
• 2011

One of the major reasons for fierce competition among firms is that they strive to increase their own market shares in the same market with similar and apparently undifferentiated products in terms of quality and perceived benefit. Due to such changes in the marketing environment, differentiated after-sales service and diversified promotion strategies have become more important in the race to gain a competitive advantage. Price discount is one of the popular promotion strategies that most retailers use, especially to increase sales, but offering a price discount does not always lead to the expected result. If marketers apply an identical price-promotion strategy without considering the characteristic differences in products and consumer preferences, the discounted price itself may make people skeptical about the quality of the product. Moreover, the changes in perceived value may appear differently depending on factors such as consumer involvement. This implies that variables such as the level of consumer involvement, brand loyalty, and external reference prices, in reality, would have different effects on how consumers perceive the value of price discounts. The variables that affect consumers' perceived values and buying decisions are diverse and complicated. Several studies have examined the effects of such variables as external reference price, selling price, and brand on consumers' perceived value of products. Results have not shown consistent patterns. Therefore, we must note that the factors affecting consumers' value perceptions and buying behaviors are diverse and that the results of studies on the same dependent variable come out differently depending on what that variable is. This study focused on the level of consumer involvement as a salient variable that supposedly affects the perceived value of a product, willingness to buy, and search intentions. We tried to examine whether a price discount affects the perceived value-such as perceived acquisition value and perceived transaction value-in different ways depending on the level of consumer involvement. In addition, we proposed managerial implications that marketers need to consider as a whole, for instance, product attributes, brand loyalty, and involvement and then established a differentiated pricing strategy, case by case, in order to effectively enhance consumers' perceived values. As a result, we found that perceived transaction value positively affects perceived acquisition value and when discounting the price of a high-involvement product enhances the consumer's willingness to buy, but perceived acquisition value does not affect the search intentions significantly. In the case of discounting prices of low-involvement products, on the other hand, the perceived transaction value has a positive effect on the willingness to buy, but the negative effect of perceived acquisition value on the search intentions was not significant. We suppose that people doubt a product's quality because of a declined perceived quality derived from a price discount. Even though the price discount enhanced the transaction value, people eventually increased their level of searching for additional product information. From the results of this study, we suggest that marketers ought to establish an appropriate value-enhancing strategy based on the understanding of which perceived value consumers rely on more when they conduct purchasing behavior because consumers perceive the degree of importance of acquisition value or transaction value differently, depending on their level of involvement.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.41 no.2
• /
• pp.69-82
• /
• 2013

The purpose of this study is to evaluate the effect of Dulegil in Bukhansan National Park in dispersing peak climbing hikers, characterize each section of Dulegil and suggest ideas of improvement. This study was conducted based on the survey completed by visitors in all 21 sections of Dulegil. After the construction of Dulegil, the number of visit to Dulegil grew and it was analyzed that Dulegil attracted new visitors given that the rate of young people(aged 19~30) who visited for the first time was quite high. Regarding the frequency of peak climbing, 7.6% of the respondents said "decreased" and 46.2% said "increased", showing that Dulegil's effect to disperse peak climbing hikers is nominal. Seven qualities were evaluated regarding Dulegil's level of satisfaction. Out of those seven, the quality of recreational place and taking a walk achieved high scores of 3.74 and 3.61 respectively. The quality of culture and history scored the lowest with 3.09. The analysis on the characteristic of each section of Dulegil, reason of visit, and the visitors' level of satisfaction showed that Dulegil is now regarded as a place where they can improve their health through light exercise and walking. In addition, a positive effect can be expected for a long time since there are different ways of utilizing the resources of the National Park, such as getting in touch with nature, preserving ecology, learning history and enjoying beautiful landscapes. If infrastructure and programs specific to each section of Dulegil were improved in a long-term perspective, it would be effective to encourage peak climbers and enjoy the lower parts of the mountain.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.10 no.5
• /
• pp.105-115
• /
• 2015

This study examined what effect the educational satisfaction level in the grey job project had on the business effectiveness and verified the effect the participant education satisfaction level had on the project business effectiveness ultimately by influencing the job satisfaction. This study utilized the source data of the senior job project old participant status survey of the Korea senior manpower development center which was conducted in 2013, and the non-proportional stratification sample extracting method was used which considered the project type, regional size, and cities/provinces. Sejong City was excluded from the survey target and the survey targeted 2,005 persons except for non-response or response-irrelevant persons concerning this study question. The collected material was analyzed by using SPSS WIN 21.0 program. The frequency and percentage were calculated to apprehend the general characteristic of the study target. Also, the regression analysis was conducted to examine the effect the educational satisfaction level had on the business effectiveness of the senior job project, and the hierarchical regression analysis was conducted in order to examine the mediated effect of the job satisfaction level in the effect the educational satisfaction level had on the business effectiveness of the senior job project. The main result of this study is as follows. First, among the effects the educational satisfaction level had on the business effectiveness, both interest level of educational contents and the job utilization of education had a significant effect on the psychological effect, and the interest level of the educational contents had a significant level on the physical/social effect, and the job utilization of education had a significant effect on the economic effect. Second, in the effect the educational satisfaction level had on the business effectiveness, the job satisfaction level was confirmed the job satisfaction level had a partial mediated effect in the effect the educational satisfaction level had on the psychological/physical/social effect. The job satisfaction level was confirmed the job satisfaction level had a complete mediated effect in the effect the educational satisfaction level had on the economic effect. Also, The job satisfaction level was confirmed the job satisfaction level had a partial mediated effect in the effect the educational satisfaction level had on the business effectiveness. Consequently, the educational contents according with the demand of job participants will have to be developed and the exclusive manpower must be arranged to conduct the education effectively. Also, making participants feel a pride on the job fully will largely contribute to raising the business effectiveness because the job satisfaction level has a positive effect on the business effectiveness.

• Clinical and Experimental Pediatrics
• /
• v.45 no.11
• /
• pp.1373-1380
• /
• 2002

Purpose : Acute measles encephalitis(ME) is characterized by an abrupt onset of fever and obtundation, frequently accompanied by seizures and multifocal neurological signs. The aim of this study was to clarify the clinical manifestation, progression and the brain SPECT patterns in patients with acute ME. Methods : This study included 11 children with acute ME admitted to Chonbuk National University Hospital. Ten patients received a first dose of measles vaccine, one patient did not receive a first dose, and no patients received a second dose. ME was diagnosed based on characteristic clinical pictures, measles antibodies by ELISA and abnormal CSF findings. Brain MRI and brain SPECT were performed in 11 patients with acute ME. Results : There were four males and seven females whose ages at onset ranged between 18 months and 14 years(mean : 10.5 years). The main clinical neurologic pictures were loss of consciousness( 10) and seizure(five). The titer of IgG and IgM antimeasles antibodies in serum were positive in 10 patients. In CSF, nine patients had IgG antibodies and one patient had IgM antibodies. The concentration of protein(mean : $124{\pm}60mg/dL$) and WBC counts(mean : $158{\pm}157/{\mu}L$) in CSF were elevated in all patients. In electroencephalographic examination, nine patients showed increased slow waves. Seven of 11 patients(63.6%) revealed high signal intensity on the brain MRI. In contrast, all patients showed hypoperfusion in brain SPECT examination. According to brain SPECT, the perfusion deficits were frequently observed in the frontal lobe(nine), temporal (nine), parietal(eight) and thalamus(eight). Conclusion : Brain SPECT is more sensitive than MRI for the evaluation of brain damage in early stages of acute ME.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.5
• /
• pp.664-672
• /
• 2015

In order to develop new immuno-stimulating ingredients from mature leaves of green tea, crude polysaccharides were isolated from pectinase digests of tea leaves (green tea enzyme digestion, GTE-0), after which their immuno-stimulating activities and chemical properties were examined. GTE-0 mainly contained neutral sugars (54.9%) such as glucose (14.2%), arabinose (12.2%), rhamnose (11.1%), and galacturonic acid (45.1%), which are characteristic of pectic polysaccharides. The anti-complementary activity of GTE-0 was similar to that of polysaccharide K (used as positive control). Number of morphologically activated macrophages was significantly increased in the GTE-0-treated group. GTE-0 significantly augmented $H_2O_2$ and reactive oxygen species production by murine peritoneal macrophage cells in a dose-dependent manner, whereas production of nitric oxide showed the highest activity at a dose of $100{\mu}g/mL$ among all tested concentrations. Murine peritoneal macrophages stimulated with GTE-0 showed enhanced production of various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factors-${\alpha}$ in a dose-dependent manner. Further, GTE-0 induced higher phagocytic activity in a dose-dependent manner. In ex vivo assay for cytolytic activity of murine peritoneal macrophages, GTE-0-treated group showed significantly higher activity compared to the untreated group at an effector-to-target cell ratio of 20. The above results lead us to conclude that polysaccharides from leaves of green tea have a potent immuno-stimulating effect on murine peritoneal macrophage cells.

• Korean Journal of Environmental Biology
• /
• v.38 no.1
• /
• pp.127-136
• /
• 2020

This study was conducted to investigate the population characteristics of Nile tilapia (Oreochromis niloticus) in the Daegu Metropolitan City thermal effluent stream (Dalseo Stream) from January to November 2019. The collected fish were identified as 4,247 individuals of 20 species from a total of eight families. The dominant species was O. niloticus with 1,306 individuals and a high relative abundance (30.75%). The water temperature of Dalseo Stream was maintained above 10℃ throughout the year, which means that O. niloticus could inhabit it even in winter. The length-weight analysis showed a regression coefficient b of 3.1496, and a condition factor (k) of 0.0025 with a positive slope. Comparing the water temperature of Dalseo Stream and the total length of O. niloticus per investigation period, the 0-age individuals appeared May 29 when the water temperature was maintained above 22℃. In conclusion, the thermal effluent of Dalseo Stream allowed O. niloticus to survive in winter and maintain stable growth conditions and life cycles. The results of this study will inform ecological information on O. niloticus, which suggests that river management efforts should consider the management of O. niloticus populations for the conservation of fish species diversity.

• Journal of Science Education
• /
• v.38 no.3
• /
• pp.525-542
• /
• 2014

This study was performed to look into the difficulty of students in understanding science stories in 6th grade science textbooks and to analyze those factors. To do this, 6th grader (N=65) were selected from J Elementary School located in Gyeonggi-do Siheung-si as study subjects. 26 science stories in 6th grade science textbooks were classified by field and context (complement of knowledge, science history of scientists, science in life, cutting-edge science technology, environment issues) in which the characteristics were investigated and analyzed. Also, a survey about the difficulty in understanding science stories(26 items) was conducted(65 students) and a semi-structured interview was conducted for students to clarify the meaning of collected data from surveys(4 students). As result of analyzing surveys on science story context in science textbooks and interviews, 4 fields of 'energy,' 'matter,' 'life,' and 'earth' were evenly mentioned. Science in life and complement of science knowledge were mentions most for context and this had relation with the characteristic of science textbooks to provide many opportunities to apply learned knowledge in actual social issues. Reactions of students on science stories were mostly positive that they help studying science, but there was also difficulty in well understanding science stories. Difficulty of understanding context, problems of context suggesting methods, difficulty of science terminology, lack of interest, and etc. were analyzed as factors. Specific causes were mentioned to be description type class, unimportant context, lack of explanation on suggested context, problem of pictures by students.

• Journal of Chest Surgery
• /
• v.37 no.8
• /
• pp.691-701
• /
• 2004

Background: Tissue hypoxia is a characteristic of many human malignant neoplasms, and hypoxia inducible factor-1 (HIF-1) plays a pivotal role in essential adaptive response to hypoxia, and activates a signal pathway for the expression of the hypoxia-regulated genes, resulting in increased oxygen delivery or facilitating metabolic adaptation to hypoxia. Increased level of HIF-1 a has been reported in many human malignancies, but in esophageal squamous cell carcinoma, the influence of HIF-1 a on tumor biology, including neovascularization, is not still defined. Material and Method: The influence of HIF-1 a expression on angiogenic factors, correlation between the tumor proliferation and HIF-1 a expression, interaction of HIF-1 a expression and p53, and correlation between HIF-1 a expression and clinicopathological prognostic parameters were investigated, using immunohistochemical stains for HIF-1 a, VEGF, CD34, p53, and Ki-67 on 77 cases of resected esophageal squamous cell carcinoma. Result: HIF-1 a expression in cancer cells was found in 33 of 77 esophageal squamous cell carcinoma cases. The 33 cases (42.9%) showed positive stain for HIF-1 a. High HIF-1 a expression was significantly associated with several pathological parameters, such as histologic grade (p=0.032), pathological TMN stage (p=0.002), the depth of tumor invasion (p=0.022), regional lymph node metastasis (p=0.002), distant metastasis (p=0.049), and lymphatic invasion (p=0.004). High HIF-1 a expression had significant VEGF immunoreactivity (p=0.008) and Ki-67 labeling index (p<0.001), but was not correlated with microvascular density within tumors (p=0.088). The high HIF-1 a expression was correlated with aberrant p53 accumulation with a marginal significance (p=0.056). The overall 5-year survival rate was 34.9%. The survival rate of patients with a high HIF-1 a expression was worse than that of patients with low-expression tumors (log-rank test, p=0.0001). High HIF-1 a expression was independent unfavorable factors although statistical significance is marginal in multivariate analysis. Conclusion: It is suggested that (1) high HIF-1 a expression in esophageal squamous cell carcinoma is associated with tumor hypoxia, or with genetic alteration in early carcinogenesis and progressive stages, (2) high HIF-1 a expression may be associated with intratumoral neovascularization through HIF-VEGF pathway, and (3) high HIF-1 a expression is associated with poor prognosis in patients with esophageal squamous cell carcinoma and may playa role as biomarker for regional lymph node metastasis.

• Pediatric Infection and Vaccine
• /
• v.25 no.2
• /
• pp.61-71
• /
• 2018

Purpose: Research on the clinical role of Staphylococcus aureus as a pathogen in acute gastroenteritis (AGE) in children has been scarce. This study aimed to clarify the prevalence and clinical correlation of S. aureus detection in children with AGE. Methods: Fecal samples were collected from children with symptoms of AGE who visited a secondary hospital between January 2012 and December 2015. The samples were sent to the Seoul Metropolitan Government Research Institute of Public Health and Environment to test for pathogenic organisms. Clinical patterns were analyzed through medical record review. Results: Among the 663 participants, the bacteria detection rate was 26.2% (n=174), the virus detection rate was 29.7% (n=197), and the non-detection rate was 43.1% (n=286). S. aureus was tested positive from 102 cases and was confirmed as a single pathogen in 53 cases. It was the third most common pathogen. The prevalence by age was highest (45.3%) in 0-2 year-olds. Most cases occurred in summer. Symptoms included diarrhea (71.7%), vomiting (67.9%), fever (49.1%), and abdominal pain (37.7%). Only vomiting showed a significant difference between the S. aureus group and the non-detection group (67.9% vs. 43.0%; P=0.001). Among enterotoxins, the higher incidence of vomiting was associated with classical staphylococcal enterotoxins (SEA, SEB, SEC, SED, and SEE) and SEH (P=0.027). Conclusions: S. aureus was the bacteria commonly isolated from children with AGE. Our study identified cases of staphylococcal AGE in children based on fecal samples and confirmed the characteristic symptoms, affected age groups, seasonal distribution, and correlation with enterotoxins.