• Clean Technology
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• v.17 no.4
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• pp.346-352
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• 2011

The adsorption characteristics of propineb pesticide onto activated carbon has been investigated for the adsorption in aqueous solution with respect to initial concentration, contact time and temperature in batch experiment. The Langmuir and Freundlich adsorption models were applied to described the equilibrium isotherms and isotherm constants were also determined. The Freundlich model agrees with experimental data well. slope of isotherm line indicate that activated carbon could be employed as effective treatment for removal of propineb. The pseudo first order, pseudo second order kinetic models were use to describe the kinetic data and rate constants were evaluated. The adsorption process followed a pseudo second order model, and the adsorption rate constant($k_2$) decreased with increasing initial concentration of propineb. The activation energy, change of free energy, enthalpy, and entropy were also calculated to predict the nature adsorption. The estimated values for change of free energy were -7.28, -8.27 and -11.66 kJ/mol over activated carbon at 298, 308 and 318 K, respectively. The results indicated toward a spontaneous process. The positive value for change of enthalpy, 54.46 kJ/mol, found that the adsorption of propineb on activated carbon is an endothermic process.

• Biomedical Science Letters
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• v.11 no.4
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• pp.465-471
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• 2005

Ofloxacin has antimycobacterial activity that possibly contributes a pivotal role in the second-line drug regimens that are used for the treatment of multidrug-resistant tuberculosis. However, in some communities, the resistance rate of Mycobacterium tuberculosis to this agent is surging. Therefore, a rapid and accurate method that can be used to determine the resistance of M tuberculosis to the ofloxacin can be very useful for effective treatment of the patients. As an effort to develop such a method, this study was set up to reveal general types of mutations that are related to ofloxacin resistance of M tuberculosis. From previous studies, it has been well known that ofloxacin resistance is associated with mutations in a gene encoding the gyrase A subunit protein. In this study, we obtained 43 ofloxacin-resistant and 50 ofloxacin-susceptible M tuberculosis clinical isolates from Masan National TB Hospital, and sequences of DNA fragment of 320 bp, region of gyrA corresponding to the ofloxacin resistance-determining region were analyzed. In brief, the results showed that a total of seven mutation types were found at gyrA. Theses mutations were all clustered within nucleotides 2574 to 2586 of the gyrA gene (codons 88 to 94). Codon 94 was the most frequently substituted site. Twenty-four of the 43 isolates had mutations at this position resulting in a total of five different types of amino acid changes $(Asp{\to}Ala,\;Asp{\to}Gly,\;Asp{\to}His,\;Asp{\to}Tyr,\;and\;Asp{\to}Asn)$. Five isolates contained a mutation at codon 90 resulting $Ala{\to}Val$ change. Four isolates had mutations at codon 91 causing a $Ser{\to}Pro$ change at this site. Two isolates contained a mutation at codon 88 and each of them resulted in different types of amino acid changes $(Gly{\to}Cys,\;Gly{\to}Ala)$. On the other hand, polymorphic site at codon 95 was found in both ofloxacin-resistant and ofloxacin-susceptible isolates. From these results, we concluded that the rate of mutations present in gyrA among ofloxacin-resistant M. tuberculosis in Korea is similar to the general rates of mutations found throughout the world. Subsequently, an oligonucleotide probe was designed based on the results of sequence analysis and was used to develop a dot blot hybridization assay system to determine ofloxacin-resistance of M tuberculosis. To evaluate this probe, dot-blot hybridization was carried out using other 57 clinical isolates, and the results showed that the dot-blot hybridization assay is good for detecting sequence alterations atgyrA gene.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.619-624
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• 2005

Background : The drug resistance rate in tuberculosis patients with history of chemotherapy is an important indicator of for evaluation of appropriateness of treatment regimens and compliance of patients. This study examined the long-term changes in the drug resistance rates among TB patients failed in treatment or reactivated. Methods : The results of drug susceptibility testing data from patients registered in health centers from 1981 to 2004 were analyzed. Results : The rate of resistance to isoniazid decreased from 90% to 20%, and the resistance to ethambutol decreased from 45% to 6%. The rate of resistance to rifampicin varied from 13% to 28% and the resistance to pyrazinamide was 5% to 10%. Multidrug resistance was about 2-3% lower than any rifampicin resistance rates. The second-line drug resistance was ranged from 1% to 3%. There was no difference between patients' genders. Patient numbers per 100,000 population increased with age. The regional distribution was even at 4-6 patients per 100,000 population, and drug resistance rates were significantly lower in big city areas than in small towns and rural areas. Conclusion : The rates of resistance of Mycobacterium tuberculosis isolated from TB patients with history of chemotherapy to isoniazid, rifampin, ethambutol, and isoniazid plus rifampin were significantly decreased during over two decades.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.73-81
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• 2010

Objective: To examine the efficacy of letrozole in infertile women showing a poor endometrial development at previous ovulation induction cycle by using clomiphene citrate. Methods: Eighteen infertile women were selected who showed a poor endometrial development (endometrial thickness$\leq$6.5 mm) after clomiphene treatment (50~100 mg) as ovulation induction for timed coitus. The mean age of the patients was $30.7{\pm}2.8$ years old and the mean duration of infertility was $33.1{\pm}26.6$ months. The infertility factors were identified as corrected endometriosis (n=1), polycystic ovary syndrome (n=5) and unexplained (n=12). Letrozole was given orally in a dose of 2.5 mg for 5 days starting 3~5 of menstrual cycle. Results: The number of follicles was significantly lower in the letrozole cycle when compared with previous clomiphene cycle ($1.1{\pm}0.3$ vs. $2.2{\pm}1.5$, p=0.011). The endometrial thickness (mm) at the time of triggering or LH surge was significantly greater in the letrozole cycle ($8.4{\pm}1.7$ vs. $5.8{\pm}0.5$, p<0.001). The endometrial pattern 'type C' was significantly higher in the letrozole cycle (94.4% vs. 50%, p=0.036). The pregnancy was achieved in 11.1% of the letrozole cycle. Conclusion: Use of letrozole was associated with more thick and improved endometrium than previous clomiphene cycles in which thin endometrium was identified. Use of letrozole appears to be an effective strategy for second-line treatment in women with inadequate endometrial response to clomiphene.

• Journal of Society of Preventive Korean Medicine
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• v.23 no.1
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• pp.27-47
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• 2019

Purpose : This study was designed to identify the perception and practice level of infection control among korean medical doctors and to identify factors that may influence the performance and practice level. Methods : Data were collected using the on­line survey method. Seven hundred and eighty four Korean medical doctors(KMD) participated the survey. The study was conducted from December 2018 to January 2019. Results : The results of this study are as follows. 1. Participants who experienced infection risk by needles or sharp instruments were 596(76%). and participants who had experienced blood or body fluid contact with the mucous membrane or skin of the patient during treatment were 226(28.8%) of them. 2. The degree of perception and practice of the infectious guideline was higher in the group over 50 years, in the doctor group, in the group with more than 6 years experience in clinic and in the group who work in the hospital. (p < 0.05) 3. In the performance of the infection control management related to the Korean medical treatment, the practice level of the article 'Discard the remaining needle that used for one patient' was the lowest at 4.02, 'Identify the patient and check the validity period of sterilization of medicines or instruments' was the second lowest in 4.16. 4. Among the contents of "Prevention of Nosocomial infection and Sanitary Safety Guidelines" issued by the Korean Medical Association in 2008, the guideline "Prevention of infection by pathogens such as HIV, MRSA, SARS" were lowest article in the perception and practice level of participants. 5. Regression analysis was performed to find out the factors affecting perception and performance of the participants. The regression model showed significant difference in the regression model of the working years. (p < 0.05) 6. In order to examine the effect of the variables on the perception and practice of the infectious guideline, the mediated effect of the knowledge and education level according to the years of working, age, education degree was found to be significant only in the education degree variable. (p < 0.05) In conclusion : in order to improve the perception and practice of infectious control of Korean medicine doctors, it is necessary to include the contents of infection management as essential education during the continuing education of Korean medicine association.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.3
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• pp.221-239
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• 2010

Bone loss may occur depending on the loading conditions. careful treatment planning and prosthetic procedures are very important factors for the proper distribution of stress. Evaluate the stress distributions according to numbers and location of implants in three-unit fixed partial dentures. A mandible missing the right second premolar, first molar and second molar was modeled. Using the CT data. we modeled a mandible with a width of 15mm, a height of 20mm and a length of 30mm, 2mm-thickness cortical bone covering cancellous bone mallow. An internal type implant and A solid type abutment was used. A model with 3 implants placed in a straight line, offset 1.5 mm buccally, offset 1.5 mm lingually and another model with 3 implants offset in the opposite way were prepared. And models with 2 implants were both end support models, a mesial cantilever model and a distal cantilever model. Three types of loading was applied; a case where 155 N was applied solely on the second premolar, a case where 206 N was applied solely on the second molar and a case where 155 N was applied on the first premolar and 206 N was applied on the first and second molar. For all the cases, inclined loads of 30 degrees were applied on the buccal cusps and vertical loads were applied on the central fossas of the teeth. Finite element analysis was carried out for each case to find out the stress distribution on bones and implants. This study has shown that prostheses with more implants caused lower stress on bones and implants, no matter what kind of load was applied. Furthermore, it was found out that inclined loads applied on implants had worse effects than vertical loads. Therefore, it is believed that these results should be considered when placing implants in the future.

• The Journal of Korean Society for Radiation Therapy
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• v.24 no.2
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• pp.107-114
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• 2012

Purpose: Unlike the existing linear accelerator with photon, proton therapy produces a number of second radiation due to the kinds of nuclide including neutron that is produced from the interaction with matter, and more attention must be paid on the exposure level of radiation workers for this reason. Therefore, thermoluminescence dosimeter (TLD) that is being widely used to measure radiation was utilized to analyze the exposure level of the radiation workers and propose a basic data about the radiation exposure level during the proton therapy. Materials and Methods: The subjects were radiation workers who worked at the proton therapy center of National Cancer Center and TLD Badge was used to compare the measured data of exposure level. In order to check the dispersion of exposure dose on body parts from the second radiation coming out surrounding the beam line of proton, TLD (width and length: 3 mm each) was attached to on the body spots (lateral canthi, neck, nipples, umbilicus, back, wrists) and retained them for 8 working hours, and the average data was obtained after measuring them for 80 hours. Moreover, in order to look into the dispersion of spatial exposure in the treatment room, TLD was attached on the snout, PPS (Patient Positioning System), Pendant, block closet, DIPS (Digital Image Positioning System), Console, doors and measured its exposure dose level during the working hours per day. Results: As a result of measuring exposure level of TLD Badge of radiation workers, quarterly average was 0.174 mSv, yearly average was 0.543 mSv, and after measuring the exposure level of body spots, it showed that the highest exposed body spot was neck and the lowest exposed body spot was back (the middle point of a line connecting both scapula superior angles). Investigation into the spatial exposure according to the workers' movement revealed that the exposure level was highest near the snout and as the distance becomes distant, it went lower. Conclusion: Even a small amount of exposure will eventually increase cumulative dose and exposure dose on a specific body part can bring health risks if one works in a same location for a long period. Therefore, radiation workers must thoroughly manage exposure dose and try their best to minimize it according to ALARA (As Low As Reasonably Achievable) as the International Commission on Radiological Protection (ICRP) recommends.

• Tuberculosis and Respiratory Diseases
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• v.45 no.3
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• pp.509-518
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• 1998

Background: Short-course chemotherapy for 6 months is well established for pulmonary tuberculosis. However, little is known about the efficacy of the short-course chemotherapy for tuberculous pleural effusion. Tuberculous pleural effusion itself may be self-limiting without any treatment, but about two thirds of the patients with tuberculous pleural effusion may subsequently develop pulmonary tuberculosis within 5 years. After completing treatment for tuberculous pleural effusion. prolonged follow-up is necessary for evaluating the efficacy of the treatment There is still no report on the efficacy of 6-month regimens for tuberculous pleural effusion in Korea, where the incidence of tuberculous disease and drug resistance is high. We studied the efficacy of 6 month short-course chemotherapy comparing with 9 month chemotherapy. Method : Retrospective study was done through medical record review in 238 patients with tuberculous pleural effusion who admitted to Asan Medical Center during May 1989-May 1993. The diagnosis of tuberculous pleural effusion was made by bacteriologic or histopathologic study. Results: Among 238 patients, 38 patients were dropped out during follow-up period. In 2 patients, second line drugs were prescribed according to known drug resistance results. And, in 23 patients, treatment longer than 9 months was done due to accompanying extrapulmonary tuberculosis or durg resistance. In 8 patients, treatment regimen was changed due to hepatotoxicity. Remaining 167 cases (70.2%) completed the treatment as scheduled ; 6 month chemotherapy in 88 cases and 9 month chemotherapy in 79 cases. In 60 patients (35.9%) with pleural effusion only in chest X-ray finding, sputum smear or culture for M.tuberculosis was positive in 6 cases (10.0%), and in 63 patients (37.7%) with radiologically inactive pulmonary tuberculosis, sputum smear or culture was positive in 18 cases (28.6%). In 44 patients (26.3%) with radiologically active pulmonary tuberculosis, the sputum smear or culture was positive in 24 cases (54.5%). In 6-month chemotherapy group (n=88), during mean 23 months (range; 1~61months) follow-up period, pulmonary tuberculosis developed in 1 case (1.4%). In 9-month chemotherapy group(n=79), during mean 23 months (range; 3~70months) follow-up period, pulmonary tuberculosis developed in 2 cases (2.5%). All the cases who developed pulmonary tuberculosis also showed active pulmonary tuberculosis on initial chest X-ray before treatment Conclusion: In patients with tuberculous pleural effusion, the incidence of pulmonary tuberculosis after 6 month chemotherapy showed no difference from that after 9 month chemotherapy. Thus, 6 month short-course chemotherapy seems to be an effective treatment for tuberculous pleural effusion.

• Asia Marketing Journal
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• v.12 no.2
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• pp.155-175
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• 2010

Most of the service industries including finance and telecommunications have become matured and saturated. The competitions have become severe while the differences among brands become smaller. Therefore maintaining good relationships with customers has been critical for the service providers. In case of credit card and debit card, the similar patterns are shown. It is important for them to maintain good relationships with customers, and therefore, they have used marketing program which provides customized services to customers and utilizes the membership programs. Not only do they build and maintain good relationships, but also highlight their brands from the emotional aspects. For example, KB Card or Hyundai Card uses well-known designers' works for their credit card design. As well, they differentiate the designs of credit cards to stress on their brand personalities. BC Card introduced the credit card with perfume that a customer would like. Even though the credit card is small and not shown to public easily, it becomes more important for those companies to touch the customers' feelings with the brand personalities and their images. This is partly because of changes in consumers' lifestyles. Y-generations becomes highly likely to express themselves in many different ways and more emotional than X-generations. For the Y-generations, therefore, even credit cards in the wallet should be personalized and well-designed. In line with it, credit cards with good design can be seen as an example of brand identity, where different design for each customer can be used to recognize the membership groups that customers want to belong. On the other hand, these credit card companies offer the special treatment benefits for those customers who are heavy users for the cards. For example, those customers who love sports will receive some special discounts when they use their credit cards for sports related products. Therefore this study attempted to explore the relationships between relational benefits, brand identification and loyalty. It has been well known that relational benefits and brand identification lead to loyalty independently from many other studies, but there has been few study to review all the three variables all together in a research model. Furthermore, as reviewed above, in the card industry, many companies attempt to associate the brand image with their products to fit their customers' lifestyles while relational benefits are still playing an important role for their business. Therefore in our research model, relational benefits, brand identification, and loyalty are all included. We focus on the mediating effect of brand identification. From the relational benefits perspective, only special treatment benefit and confidence benefit are included. Social benefit is not applicable for this credit card industry because not many cases of face-to-face interaction can be found. From the brand identification perspective, personal brand identity and social brand identity are reviewed and included in the model. Overall, the research model emphasizes that the relationships between relational benefits and loyalty will be mediated by the effect of brand identification. The effects of relational benefits which are confidence benefit and special treatment benefits on loyalty will be realized when they fit to the personal brand identity and social brand identity. In the research model, therefore, the relationships between confidence benefit and social brand identity, and between confidence benefit and personal identity are hypothesized while the effects of special treatment benefit on social brand identity and personal brand identity are hypothesized. Loyalty, then, is hypothesized to have positive relationships with personal brand identity and social brand identity. In addition, confidence benefit among the relational benefits is expected to have a direct, positive relationship with loyalty because confidence benefit has been recognized as a critical factor for good relationships and satisfaction. Data were collected from college students who have been using either credit cards or debit cards. College students were regarded good subjects because they are in Y-generation cohorts and have tendency to express themselves more. Total sample size was two hundred three at the beginning, but after deleting those data with many missing values, one hundred ninety-seven data points were remained and used for the model testing. Measurement items were brought from the previous literatures and modified for this research. To test the reliability, using SPSS 14, chronbach's α was examined and all the values were from .874 to .928 exceeding over .7. Using AMOS 7.0, confirmatory factor analysis was conducted to investigate the measurement model. The measurement model was found good fit with χ²(67)=188.388 (p= .000), GFI=.886, AGFI=.821, CFI=.941, RMSEA=.096. Using AMOS 7.0, structural equation modeling has been used to analyze the research model. Overall, the research model fit were χ²(68)=188.670 (p= .000), GFI=.886, AGFI=,824 CFI=.942, RMSEA=.095 indicating good fit. In details, all the paths hypothesized in the research model were found significant except for the path from social brand identity to loyalty. Personal brand identity leads to loyalty while both confidence benefit and special treatment benefit have a positive relationships with personal and social identities. As well, confidence benefit has a direct positive effect on loyalty. The results indicates the followings. First, personal brand identity plays an important role for credit/debit card usage. Therefore even for the products which are not shown to public easy, design and emotional aspect can be important to fit the customers' lifestyles. Second, confidence benefit and special treatment benefit have a positive effects on personal brand identity. Therefore it will be needed for marketers to associate the special treatment and trust and confidence benefits with personal image, personality and personal identity. Third, this study found again the importance of confidence and trust. However interestingly enough, social brand identity was not found to be significantly related to loyalty. It can be explained that the main sample of this study consists of college students. Those strategies to facilitate social brand identity are focused on high social status groups while college students have not been established their status yet.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.4
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• pp.231-237
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• 1973

Eeffect of temperature (3-day or 7-day treatment under $15^{\circ}C$, $20^{\circ}C$ and $25^{\circ}C$) on chlorophyll, nitrogen and potassium content in the second leaf blade from top of IR667 line (Suwon 213 and 214) and leading local varieties (Jinheung and Paldal) was investigated at the end of nursery, maximum tillering and flowering stage using phytotron. 1. Chlorophyll content was higher in IR667 line than in the local at $25^{\circ}C$ but reversed at $20^{\circ}C$ or $15^{\circ}C$ and chlorophyll a/b value was always high in the local. 2. Chlorophyll content per fresh weight decreased with growth and low temperature effect was greater at the end of nursery and on chlorophyll a than on chlorophyll b. 3. Chlorophyll a/b value increases with the increase of chlorophyll content and the increasing rate of chl. a/b value per chlorophyll increment tends to decrease under unfavorable condition. This decrease is greater in low temperature sensitive IR667 than local varieties. 4. According to chlorophyll retention value IR667 line was weaker at low temperature. 5. The content of total nitrogen or soluble nitrogen (methanol soluble) was decreased by low temperature. 6. Chl. (a+b)/S-N value decreased with growth and seemed not to be greatly affected by temperature and always higher in the local. 7. Potassium content (total or methanol soluble) tends to decrease at low temperature and soluble K increased with chlorophyll content. 8. High yielding ability of IR667 seems to be attributable to its high chlorophyll content at high temperature and easy leaf discoloration by low temperature or by nitrogen depression of IR667 seems to be attributable to the low Chl./S-N value.