• Korean journal of applied entomology
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• v.48 no.2
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• pp.123-158
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• 2009

An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.

• Tuberculosis and Respiratory Diseases
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• v.55 no.2
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• pp.175-187
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• 2003

Background : Although corticosteroid and cytotoxic agent such as cyclophosphamide have been used for the treatment idiopathic interstitial pneumonia (IIP), efficacy of these toxic drugs are unclear because previous reports included the patients who did not undergo surgical lung biopsy and none evaluated the response according to histopathologic entities of IIP. To answer this, we retrospectively analyzed the treatment response and side effects of corticosteroids and cyclophosphamide therapy in patients with idiopathic UIP and NSIP. Methods : Among 61 patients with UIP and 26 patients with NSIP diagnosed by surgical lung biopsy at Samsung Medical Center from July 1996 to June 2002, those who received corticosteroid or cyclophosphamide therapy for at least 6 months and were followed for at least one year after the initiation of treatment were enrolled (32 UIP, 23 NSIP). Treatment response of 55 patients was assessed by ATS response criteria (clinical symptoms, pulmonary function test and radiological findings). Adverse reactions to either agent (42 cases of cyclophosphamide${\pm}$low-dose prednisolone, 49 cases of prednisolone alone) were also analyzed. Results : Irrespective of treatment regimen, NSIP showed more favorable response than UIP (6 months: 78.3% vs. 9.4%, 12 months: 69.6% vs. 9.4%, p<0.001). Cyclophosphamide showed comparable response to corticosteroid in NSIP while its efficacy was as poor as those of corticosteroid therapy in UIP. Significant adverse reaction to drug more frequently occurred in corticosteroid group (35.7%) than cyclophosphamide group (14.3%) (p=0.017). Conclusion : Cyclophosphamide is effective and more tolerable than corticosteroids in the treatment of idiopathic nonspecific interstitial pneumonia.

• Journal of Gastric Cancer
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• v.6 no.3
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• pp.161-166
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• 2006

Purpose: Recently, the incidence of early gastric cancer (EGC) patients is rapidly increased in Korea. However, they're often not perceptible by surgical palpation or inspection. The aim of this study is 1) to develope a software that can locate the tumor and measure the mucosal distance from an anatomic landmark to the tumor using CT gastrography and 2) to compare the distance measured by the developed software with the distance measured by the pathologic findings. Materials and Methods: Between January 2004 and September 2005, sixty patients (male=45, female=15, mean 57.8 years old) estimated for EGC with preoperative CT scans and undergone gastrectomies in Kyungpook National University Hospital were enrolled in this study. Preoperative CT scans were performed after insufflations of room air via 5 Fr NG tube. The scans included the following parameters: (slice thickness/reconstruction interval: 0.625 mm, kVp: 120, mAs: 200). 3D volume rendering and measurement of the surface distance from the pylorus to the EGC were performed using the developed software. Results: The average difference between the lesion to pylorus distances measured from pathologic specimens and CT gastrography was $5.3{\pm}2.9\;mm(range,\;0{\sim}23\;mm)$. The lesion to pylorus distance measured from CT gastrography was well correlated with that measured from the pathologic specimens (r=0.9843, P<0.001). Conclusion: These results suggest that the surface distance from an anatomic landmark to the EGC can be measured accurately by CT gastrography. This technique could be used for preoperative localization of early gastric carcinomas to determine the optimal extent of surgical resection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1041-1048
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• 2016

Biofilm cells and viable but non-culturable (VBNC) state may play a role in the survival of Campylobacter jejuni under unfavorable environmental conditions. The objective of this study was to investigate the behavior of C. jejuni biofilm cells and VBNC cells on smoked duck. The transfer of C. jejuni biofilm cells to smoked duck and its ability to resuscitate from biofilm and VBNC cells on smoked duck was investigated. Transfer experiments were conducted from C. jejuni biofilm cells to smoked duck after 5 min, 1 h, 3 h, and 24 h contact at room temperature, and the efficiency of transfer (EOT) was calculated. In addition, smoked duck was inoculated with C. jejuni biofilm and VBNC cells and then stored at 10, 24, 36, and $42^{\circ}C$ to examine the cells' ability to resuscitate on smoked ducks. The 5 min contact time between C. jejuni biofilm cells and smoked duck showed a higher EOT (0.92) than the 24 h contact time (EOT=0.08), and the EOT decreased as contact time increased. Furthermore, C. jejuni biofilm cells on smoked duck were not recovered at 10, 24, and $36^{\circ}C$, and C. jejuni VBNC cells were not resuscitated at $42^{\circ}C$. Although the resuscitation of C. jejuni biofilm and VBNC cells was not observed on smoked duck, microbial criteria of C. jejuni is needed in poultry and processed poultry products due to risk of its survival and low infectious dose.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.3
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• pp.199-206
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• 2010

This study investigated the effects of strontium on osteoblastic phenotypes of cultured human periostealderived cells. Periosteal tissues were harvested from mandible during surgical extraction of lower impacted third molar. Periosteal-derived cells were introduced into cell culture. After passage 3, the periostealderived cells were further cultured for 28 days in an osteogenic induction DMEM medium supplemented with fetal bovine serum, ascorbic acid 2-phosphate, dexamethasone and at a density of $3{\times}10^4$ cells/well in a 6-well plate. In this culture medium, strontium at different concentrations (1, 5, 10, and 100 ${\mu}g$/mL) was added. The medium was changed every 3 days during the incubation period. We examined the cellular proliferation, histochemical detection and biochemical measurements of alkaline phosphatase (ALP), the RT-PCR analysis for ALP and osteocalcin, and von Kossa staining and calcium contents in the periostealderived cells. Cell proliferation was not associated with the addition of strontium in periosteal-derived cells. The ALP activity in the periosteal-derived cells was higher in 5, 10, and 100 ${\mu}g$/ml strontium-treated cells than in untreated cells at day 14 of culture. Among the strontium-treated cells, the ALP activity was appreciably higher in 100 ${\mu}g$/ml strontium-treated cells than in 5 and 10 ${\mu}g$/ml strontium-treated cells. The levels of ALP and osteocalcin mRNA in the periosteal-derived cells was also higher in strontium-treated cells than in untreated cells at day 14 of culture. Their levels were increased in a dose-dependent manner. Von Kossa-positive mineralization nodules were strongly observed in the 1 ${\mu}g$/ml strontium-treated cells at day 21 and 28 of culture. The calcium content in the periosteal-derived cells was also higher in 1 ${\mu}g$/ml strontium-treated cells at day 28 of culture. These results suggest that low concentration of strontium stimulates the osteoblastic phenotypes of more differentiated periosteal-derived cells, whereas high concentration of strontium stimulates the osteoblastic phenotypes of less differentiated periosteal-derived cells. The effects of strontium on osteoblastic phenotypes of periosteal-derived cells appear to be associated with differentiation-extent.

• Journal of Aquaculture
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• v.9 no.2
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• pp.141-149
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• 1996

Effects of $17{\alpha}$-methyltestosterone ($17{\alpha}-MT$) in rearing water on sex reversal of Nile tilapia (Oreochromis niloticus) were investigated and optimum conditions as initial treatment time, concentrations and treatment durations of hormone were evaluated in this study. For the study of the optimum initial treatment time, 0 to 20-day-old fry were treated by immersion in a 500 ppb solution of $17{\alpha}-MT$. Desirable results were obtained at 12-day-old fish as $86.4\%$ of male induction rates and this frequency was obviously higher than the other age groups. Twelve-day-old fry were immersed in $17{\alpha}-MT$ solutions at concentrations of $0\~2,000$ ppb for 24 hours for the study of dose dependent relationship between sex ratios and concentrations of $17{\alpha}-MT$, Male induction rates of all treated groups were higher than $80\%$, $X^2$ values against the sex ratio of control group indicate that sex reversal has taken place effectively in all experimental groups (P<0.001). Futhermore, 500 ppb treated groups showed highest male incidence of $86.4\%$. Effects of 5 different durations (0, 12, 18, 24 and 30 hours) treated with 1,000 ppb of $17{\alpha}-MT$ were also evaluated. Male induction rate from 0 to 24 hours treated group was increased with treatment durations. However, male incidence of 30-hour treated group ($84.0\%$) was sligthly decreased compare to the 24-hour treated group ($85.2\%$). It is concluded that immersion treatment using $17{\alpha}-MT$ on O. niloticus is possible on sex reversal at low concentration of 500 ppb and short treatment durations within 24 hours with 12-old-day fry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1753-1759
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• 2009

The present study was conducted to investigate the effects of components obtained from Zanthoxylum schinifolium and Zanthoxylum piperitum on rancidity and quality of Kwamegi (semi-dried Pacific saury, Coloabis saira). Ethanol extract (ZS) of Zanthoxylum schinifolium leaves or the essential oil (ZP) obtained from pericarp of Zanthoxylum piperitum in 1 or 20% ethanol solution was sprayed to the Pacific saury before Kwamegi preparation at its final concentrations of 0.125~2 ppm in the Kwamegi. The prepared Kwamegi was vacuum packed with multi-layered film (polyethylene/polyamide/EVOH/polyethylene, thickness 80 μm) and kept at -20${^{\circ}C}$ until use. After opening the package Kwamegi was stored at 4${^{\circ}C}$ for 1, 3 and 7 days during which rancidity tests and sensory evaluation were carried out. Acid, peroxide, and thiobarbituric acid (TBA) values increased with storage time but reduced significantly by the addition of ZS at the concentrations of ≥G0.125 ppm and ZP≥F0.25 ppm. The effects of ZS and ZP were dose-dependent and more pronounced as storage time prolonged. The ZS and ZP also reduced dimethyamine and trimethyamine (TMA) contents which were increased with time, while they prevented the decrease of trimethyamine oxide. The ZS at the concentration of ≥G0.25 ppm and the ZP at >0.5 ppm were needed to maintain TMA less than 4.5 mg/100 g for 3 day storage at 4${^{\circ}C}$. Sensory evaluation of the Kwamegi exhibited a slightly higher preference with the ZS and ZP treated ones at the level of 0.25~0.5 ppm. It is concluded that very low amounts of ZS and ZP are effective in suppression of rancidity of Kwamegi and could be utilized for its quality management.

• Tuberculosis and Respiratory Diseases
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• v.60 no.4
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• pp.419-425
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• 2006

Background : Severe community-acquired pneumonia (CAP) can develop into respiratory failure that requires mechanical ventilation (MV), which is associated with a higher rate of mortality. It was recently reported that a hydrocortisone infusion in severe CAP patients was associated with a significant reduction in the length of the hospital stay and mortality. This study evaluated efficacy of a hydrocortisone infusion for patients with severe CAP requiring MV. Methods : From February 2005 to July 2005, 13 patients (M : F = 10 : 3, mean age: $68.6{\pm}14.1years$), who were diagnosed with severe CAP and required MV, were enrolled in this study. Hydrocortisone was administered as an intravenous 200mg loading bolus, which was followed by an infusion at a rate of 10mg/hour for 7 days. The control group was comprised of patients with severe CAP requiring MV but in whom corticosteroid was not used before study period. The clinical and physiologic parameters on or by day 8 and the outcome in the hydrocortisone infusion group were compared with those in the control group. Results : 1) There was no significant difference in age, gender ratio, SAPS II, SOFA score, temperature, leukocyte count, PaO2/FiO2 (P/F) ratio, the number of patients with P/F ratio < 200, chest radiograph score, lung injury score and catecholamine-dependent septic shock between the hydrocortisone infusion group and control group at day 1. 2) At day 8, the proportion of patients with an improvement in the P/F ratio ${\geq}100$ and the chest radiograph score was significantly higher in the hydrocortisone infusion group than in the control group (61.5% vs. 15.4%, 76.9% vs. 23.1%, p< 0.05). However, there was no significant difference in the other clinical and physiologic parameters. 3). There was no significant difference in the duration of the MV, ICU stay, hospital stay and 10th and 30th day mortality between the two groups. Conclusion : Hydrocortisone infusion for patients with severe CAP requiring invasive mechanical ventilation may be effective in improving the level of oxygenation and the chest radiograph score.

• Tuberculosis and Respiratory Diseases
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• v.62 no.4
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• pp.284-289
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• 2007

Background: To define the clinical features of patients with lung and upper aerodigestive tract cancer through a review of the histopathology, clinical features and follow-up results. Methods: Patients with lung and upper aerodigestive tract cancer who were diagnosed in Young dong Severance Hospital from 1992 to 2005, were retrospectively reviewed. The clinical data, radiologic findings, pathologic findings, treatment modalities were evaluated. Result: There was a total of 20 patients with aerodigestive tract cancer who were diagnosed with lung cancer over a 13 years period. The mean age was $58.45{\pm}15.09$ years and 19 cases were male. There were 14 smokers with an average pack year of 46 years. Twelve patients had aerodigestive tract cancer and later developed lung cancer, and 5 lung cancer patients were later diagnosed with aerodigestive tract cancer. Conclusion: These results suggest that cancers of the aerodigestive tract and lung can arise as either dependent or independent events and most aerodigestive tract cancer patients who developed lung cancer are not treated properly. Therefore, regular low dose chest CT with close suspicion is needed to properly manage upper aerodigestive tract cancer patients.

• Asia pacific journal of information systems
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• v.18 no.2
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• pp.1-14
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• 2008

According to technology acceptance model(TAN) which is one of the most important research models for explaining IT users' behavior, on intention of using IT is determined by usefulness and ease of use of it. However, TAM wouldn't explain the performance of using IT while it has been considered as a very good model for prediction of the intention. Many people would not be confirmed in the performance of using IT until they can control it at their will, although they think it useful and easy to use. In other words, in addition to usefulness and ease of use as in TAM, controllability is also should be a factor to determine acceptance of IT. Especially, there is a very close relationship between controllability and ease of use, both of which explain the other sides of control over the performance of using IT, so called perceived behavioral control(PBC) in social psychology. The objective of this study is to identify the relationship between ease of use and controllability, and analyse the effects of both two beliefs over performance and intention in using IT. For this purpose, we review the issues related with PBC in information systems studies as well as social psychology, Based on a review of PBC, we suggest a research model which includes the relationship between control and performance in using IT, and prove its validity empirically. Since it was introduced as qa variable for explaining volitional control for actions in theory of planned behavior(TPB), there have been confusion about concept of PBC in spite of its important role in predicting so many kinds of actions. Some studies define PBC as self-efficacy that means actor's perception of difficulty or ease of actions, while others as controllability. However, this confusion dose not imply conceptual contradiction but a double-faced feature of PBC since the performance of actions is related with both self-efficacy and controllability. In other words, these two concepts are discriminated and correlated with each other. Therefore, PBC should be considered as a composite concept consisting of self-efficacy and controllability, Use of IT has been also one of important areas for predictions by PBC. Most of them have been studied by analysis of comparison in prediction power between TAM and TPB or modification of TAM by inclusion of PBC as another belief as like usefulness and ease of use. Interestingly, unlike the other applications in social psychology, it is hard to find such confusion in the concept of PBC in the studies for use of IT. In most of studies, controllability is adapted as PBC since the concept of self-efficacy is included in ease of use explicitly. Based on these discussions, we can suggest perceived use control(PUC) which is defined as perception of control over the performance of using IT and composed of controllability and ease of use as sub-concepts. We suggest a research model explaining acceptance of IT which includes the relationships of PUC with attitude and performance of using IT. For empirical test of our research model, two user groups are selected for surveying questionnaires. In the first group, there are freshmen who take a basic course for Microsoft Excel, and the second group consists of senior students who take a course for analysis of management information by Excel. Most of measurements are adapted ones that have been validated in the other studies, while performance is real score of mid-term in each class. In result, four hypotheses related with PUC are supported statistically with very low significance level. Main contribution of this study is suggestion of PUC through theoretical review of PBC. Specifically, a hierarchical model of PUC are derived from very rigorous studies in the relationship between self-efficacy and controllability with a view of PBC in social psychology. The relationship between PUC and performance is another main contribution.