• Title/Summary/Keyword: spontaneous use

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Study on Adsorption Kinetic Characteristics of Propineb Pesticide on Activated Carbon (활성탄에 대한 프로피네브 농약의 흡착동력학적 특성 연구)

  • Lee, Jong-Jib;Cho, Jung-Ho;Kim, Heung-Tae
    • 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.

Effect of DA-6034, a Derivative of Flavonoid, on Experimental Animal Models of Inflammatory Bowel Disease

  • Kim, You-Sun;Son, Mi-Won;Ko, Jun-Il;Cho, Hyeon;Yoo, Moo-Hi;Kim, Won-Bae;Song, In-Sung;Kim, Chung-Yong
    • Archives of Pharmacal Research
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    • v.22 no.4
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    • pp.354-360
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    • 1999
  • Inflammatory bowel disease (IBD) is a multifactorial disorder with unknown etiology and pathogenesis. DA-6034,$ 7-carboxymethyloxy-3^{l}, 4^{l},$ 5-trimethoxy flavone, is a synthetic flavonoid known to possess anti-inflammatory activity. This study was performed to evaluate the oral therapeutic effect of DA-6034 in three experimental animal models of IBD : two chemical-induced IBD models of rats and the human leukocyte antigen (HLA)-B27 transgenic rat model known to develop spontaneous colitis without the use of exogenous agents. Acute chemical colitis was induced by intracolonic instillation of 1.2 ml of 4% acetic acid solution. Prednisolone (1 mg/kg), sulfasalazine (100 mg/kg) and DA-6034 (0.3~3 mg/kg) were orally administered twice daily for 6 days in these rats. In addition, chronic chemical colitis was induced by intracolonic administration of trinitrobenzene sulfonic acid (TNBS) 30 mg in 50% ethanol and agents were orally administered for 6 or 20 days. In chemical-induced IBD models, all of these agents reduced the severity of colitis and specially, DA-6034 (3 mg/kg) showed more potent effect than other drugs in macroscopic lesion score. In HLA-B27 transgenic rats, DA-6034 (3 mg/kg) and prednisolone (0.5 gm/kg) were treated orally twice daily for 6 weeks. The HLA-B27 transgenic rats showed only mild colitis, compared with the chemical-induced colitis models. DA-6034 ameliorated the loose stool and decreased microscopic damage, which is the important indicator of this model. In conclusion, oral therapy of DA-6034 attenuated the macroscopic and histologic damages of the colon in all three experimental models of IBD, which suggest that DA-6034 could be a promising drug in the treatment of IBD.

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Prevalence of Balanced Chromosomal Translocations in Couples with Abnormal Reproductive Outcomes and Prenatal Cytogenetic Diagnosis in the Carriers (비정상 산과력을 가진 부부에서의 균형전좌형 염색체 보인자의 빈도 및 그 보인자들에서의 산전 세포유전학적 진단)

  • Part, So-Yeon;Kang, Inn-Soo;Ryu, Hyun-Mee;Jun, Jong-Young;Lee, Moon-Hee;Kim, Jin-Mi;Choi, Soo-Kyung
    • Clinical and Experimental Reproductive Medicine
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    • v.24 no.3
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    • pp.393-398
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    • 1997
  • Cytogenetic analysis was performed in 1321 couples and 141 women with history of abnormal reproductive outcome during 1988-1996. The use of high resolution banding technique and fluorescence in situ hybridization (FISH) in the chromosome analysis has made the precise evaluation of chromosome aberrations. The prevalence of balanced chromosomal translocation carriers were 3.74% (104/2783 patients). 70 cases (2.52%) were reciprocal translocation carriers and 34 (1.22%) had Robertsonian translocations. Chromosome aberrations were more frequent in women (73 cases) than in men (31 cases). No phenotypical abnormalities were found in all carriers, but they experienced abnormal reproductive outcomes such as recurrent spontaneous abortions, anomalous offsprings or infertility problem. Prenatal diagnosis was carried out on 36 subsequent pregnancies in balanced translocation carriers. The fetal karyotypes showed that 12 cases (33%) were normal, 22 (61%) were balanced translocations, and two (6%) were unbalanced translocations. It is concluded that the prevalence of balanced chromosomal translocations in patients with abnormal reproductive outcome is higher than that of the normal population. Most of the fetal samples showed normal karyotypes or balanced translocations. Although the incidence of chromosomal imbalance in the fetuses was relatively low in prenatal diagnosis, individuals with balanced translocations are predisposed to abnormal offspring with partial trisomy or monosomy. Therefore we recommend that genetic counselling and cytogenetic prenatal diagnosis for translocation carriers have to be offered to prevent recurrent chromosomal abnormal babies.

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Large-Area Synthesis of High-Quality Graphene Films with Controllable Thickness by Rapid Thermal Annealing

  • Chu, Jae Hwan;Kwak, Jinsung;Kwon, Tae-Yang;Park, Soon-Dong;Go, Heungseok;Kim, Sung Youb;Park, Kibog;Kang, Seoktae;Kwon, Soon-Yong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.130.2-130.2
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    • 2013
  • Today, chemical vapor deposition (CVD) of hydrocarbon gases has been demonstrated as an attractive method to synthesize large-area graphene layers. However, special care should be taken to precisely control the resulting graphene layers in CVD due to its sensitivity to various process parameters. Therefore, a facile synthesis to grow graphene layers with high controllability will have great advantages for scalable practical applications. In order to simplify and create efficiency in graphene synthesis, the graphene growth by thermal annealing process has been discussed by several groups. However, the study on growth mechanism and the detailed structural and optoelectronic properties in the resulting graphene films have not been reported yet, which will be of particular interest to explore for the practical application of graphene. In this study, we report the growth of few-layer, large-area graphene films using rapid thermal annealing (RTA) without the use of intentional carbon-containing precursor. The instability of nickel films in air facilitates the spontaneous formation of ultrathin (<2~3 nm) carbon- and oxygen-containing compounds on a nickel surface and high-temperature annealing of the nickel samples results in the formation of few-layer graphene films with high crystallinity. From annealing temperature and ambient studies during RTA, it was found that the evaporation of oxygen atoms from the surface is the dominant factor affecting the formation of graphene films. The thickness of the graphene layers is strongly dependent on the RTA temperature and time and the resulting films have a limited thickness less than 2 nm even for an extended RTA time. The transferred films have a low sheet resistance of ~380 ${\Omega}/sq$, with ~93% optical transparency. This simple and potentially inexpensive method of synthesizing novel 2-dimensional carbon films offers a wide choice of graphene films for various potential applications.

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Mutation of rpsL Gene in Streptomycin-Resistant Pseudomonas syringae pv. actinidiae Biovar 3 Strains Isolated from Korea (국내에서 분리된 Streptomycin 저항성 Pseudomonas syringae pv. actinidiae Biovar 3 균주에서 rpsL 유전자의 돌연변이)

  • Lee, Young Sun;Kim, Gyoung Hee;Koh, Young Jin;Jung, Jae Sung
    • Research in Plant Disease
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    • v.28 no.1
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    • pp.26-31
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    • 2022
  • Pseudomonas syringae pv. actinidiae (Psa) is the causal agent responsible for the bacterial canker disease of kiwifruit plants. Psa strains are divided into five different biovars based on genetic and biochemical characteristics. Among them, biovar 2 and 3 strains of Psa were isolated and have been causing widespread damages in Korea. One of the most effective ways to control Psa is to use an antibiotic such as streptomycin. However, Psa strains resistant to this antibiotic were isolated in Korea, and an earlier study revealed that the resistance in the biovar 2 is associated with strA-strB genes. This study aimed to determine the molecular resistance mechanism of Psa biovar 3 strains to streptomycin. Sequencing the rpsL gene encoding ribosomal protein S12 from three streptomycin-resistant strains screened in the laboratory revealed that a spontaneous mutation occurred either at codon 43 or 88. Meanwhile, in four streptomycin-resistant strains of Psa biovar 3 isolated from two kiwifruit orchards, a single nucleotide in codon 43 of the rpsL, which is AAA in streptomycin-sensitive strain, was substituted for AGA causing an amino acid change from lysine to arginine. The resistant mechanism in all biovar 3 strains obtained in Korea was identified as a mutation of the rpsL gene.

An Evaluation of Minimum Explosible Concentration and Explosion Severity of Coal Dust in a Thermal Power Plant (화력발전소용 석탄분진의 최소폭발농도와 폭발강도 평가)

  • Yeosong Yoon;Keun-won Lee
    • Journal of the Korean Institute of Gas
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    • v.27 no.4
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    • pp.62-69
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    • 2023
  • The use of low-grade coal is continuously increasing with the development of combustion technology and cost reduction for coal used in thermal power plants . During combustion, the latent heat of evaporation due to moisture is large, and there is a risk of spontaneous combustion and dust explosion during the process of storing and pulverizing coal. This study compared and evaluated the minimum explosive concentration and explosive strength of four types of coal dust-fine, coal dust-coarse, wood pallet+organic dust, and wood chip with coal powder collected from domestic power plant D. The minimum explosive concentration of coal dust was measured according to JIS Z 8818:2002, and the explosion strength was tested according to ASTM E1226 using a Siwek 20 L Chamber Apparatus. As a result of the minimum explosive concentration test, it was found that coal dust-fine has a risk of dust explosion, and since an explosion occurs at a dust concentration of 130 g/m3 of wood chips, it was found that there is a risk of explosion at the lowest dust concentration. According to the dust explosion class standard, Kst is less than 200 bar m/s, and all samples fall under the explosion class St 1, and the dust has a low risk of explosion.

Telemedicine Protocols for the Management of Patients with Acute Spontaneous Intracerebral Hemorrhage in Rural and Medically Underserved Areas in Gangwon State : Recommendations for Doctors with Less Expertise at Local Emergency Rooms

  • Hyo Sub Jun;Kuhyun Yang;Jongyeon Kim;Jin Pyeong Jeon;Sun Jeong Kim;Jun Hyong Ahn;Seung Jin Lee;Hyuk Jai Choi;In Bok Chang;Jeong Jin Park;Jong-Kook Rhim;Sung-Chul Jin;Sung Min Cho;Sung-Pil Joo;Seung Hun Sheen;Sang Hyung Lee
    • Journal of Korean Neurosurgical Society
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    • v.67 no.4
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    • pp.385-396
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    • 2024
  • Previously, we reported the concept of a cloud-based telemedicine platform for patients with intracerebral hemorrhage (ICH) at local emergency rooms in rural and medically underserved areas in Gangwon state by combining artificial intelligence and remote consultation with a neurosurgeon. Developing a telemedicine ICH treatment protocol exclusively for doctors with less ICH expertise working in emergency rooms should be part of establishing this system. Difficulties arise in providing appropriate early treatment for ICH in rural and underserved areas before the patient is transferred to a nearby hub hospital with stroke specialists. This has been an unmet medical need for decades. The available reporting ICH guidelines are realistically applicable in university hospitals with a well-equipped infrastructure. However, it is very difficult for doctors inexperienced with ICH treatment to appropriately select and deliver ICH treatment based on the guidelines. To address these issues, we developed an ICH telemedicine protocol. Neurosurgeons from four university hospitals in Gangwon state first wrote the guidelines, and professors with extensive ICH expertise across the country revised them. Guidelines and recommendations for ICH management were described as simply as possible to allow more doctors to use them easily. We hope that our effort in developing the telemedicine protocols will ultimately improve the quality of ICH treatment in local emergency rooms in rural and underserved areas in Gangwon state.

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation

  • Hong Jun Park;Byung-Wook Kim;Jun Kyu Lee;Yehyun Park;Jin Myung Park;Jun Yong Bae;Seung Young Seo;Jae Min Lee;Jee Hyun Lee;Hyung Ku Chon;Jun-Won Chung;Hyun Ho Choi;Myung Ha Kim;Dong Ah Park;Jae Hung Jung;Joo Young Cho;Endoscopic Sedation Committee of Korean Society of Gastrointestinal Endoscopy
    • Clinical Endoscopy
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    • v.55 no.2
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    • pp.167-182
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    • 2022
  • Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Cardiopulmonary complications are usually temporary. Most patients recover without sequelae. However, they may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

The Effect of Nasal BiPAP Ventilation in Acute Exacerbation of Chronic Obstructive Airway Disease (만성 기도폐쇄환자에서 급성 호흡 부전시 BiPAP 환기법의 치료 효과)

  • Cho, Young-Bok;Kim, Ki-Beom;Lee, Hak-Jun;Chung, Jin-Hong;Lee, Kwan-Ho;Lee, Hyun-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.190-200
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    • 1996
  • Background : Mechanical ventilation constitutes the last therapeutic method for acute respiratory failure when oxygen therapy and medical treatment fail to improve the respiratory status of the patient. This invasive ventilation, classically administered by endotracheal intubation or by tracheostomy, is associated with significant mortality and morbidity. Consequently, any less invasive method able to avoid the use of endotracheal ventilation would appear to be useful in high risk patient. Over recent years, the efficacy of nasal mask ventilation has been demonstrated in the treatment of chronic restrictive respiratory failure, particularly in patients with neuromuscular diseases. More recently, this method has been successfully used in the treatment of acute respiratory failure due to parenchymal disease. Method : We assessed the efficacy of Bilevel positive airway pressure(BiPAP) in the treatment of acute exacerbation of chronic obstructive pulmonary disease(COPD). This study prospectively evaluated the clinical effectiveness of a treatment schedule with positive pressure ventilation via nasal mask(Respironics BiPAP device) in 22 patients with acute exacerbations of COPD. Eleven patients with acute exacerbations of COPD were treated with nasal pressure support ventilation delivered via a nasal ventilatory support system plus standard treatment for 3 consecutive days. An additional 11 control patients were treated only with standard treatment. The standard treatment consisted of medical and oxygen therapy. The nasal BiPAP was delivered by a pressure support ventilator in spontaneous timed mode and at an inspiratory positive airway pressure $6-8cmH_2O$ and an expiratory positive airway pressure $3-4cmH_2O$. Patients were evaluated with physical examination(respiratory rate), modified Borg scale and arterial blood gas before and after the acute therapeutic intervention. Results : Pretreatment and after 3 days of treatment, mean $PaO_2$ was 56.3mmHg and 79.1mmHg (p<0.05) in BiPAP group and 56.9mmHg and 70.2mmHg (p<0.05) in conventional treatment (CT) group and $PaCO_2$ was 63.9mmHg and 56.9mmHg (p<0.05) in BiPAP group and 53mmHg and 52.8mmHg in CT group respectively. pH was 7.36 and 7.41 (p<0.05) in BiPAP group and 7.37 and 7.38 in cr group respectively. Pretreatment and after treatment, mean respiratory rate was 28 and 23 beats/min in BiPAP group and 25 and 20 beats/min in CT group respectively. Borg scale was 7.6 and 4.7 in BiPAP group and 6.4 and 3.8 in CT group respectively. There were significant differences between the two groups in changes of mean $PaO_2$, $PaCO_2$ and pH respectively. Conclusion: We conclude that short-term nasal pressure-support ventilation delivered via nasal BiPAP in the treatment of acute exacerbation of COPD, is an efficient mode of assisted ventilation for improving blood gas values and dyspnea sensation and may reduce the need for endotracheal intubation with mechanical ventilation.

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Clinical Characteristics of Pneumococcal Bacteremia in Adults : The Effect of Penicillin Resistance on the Mortality of Patients with Pneumococcal Bacteremia (폐렴구균 균혈증에서 폐렴구균의 페니실린 내성 여부가 사망률에 미치는 영향)

  • HwangBo, Bin;Yoon, Ho-Il;Lee, Sang-Min;Choi, Seung-Ho;Park, Gye-Young;Yoo, Chul-Gyu;Lee, Choon-Taek;Kim, Young-Whan;Han, Sung-Koo;Min, Kyung-Up;Kim, You-Young;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.2
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    • pp.184-194
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    • 1999
  • Backgrounds : The advent of penicillin has led to the marked reduction in the mortality from pneumococcal bacteremia, however, the mortality is still relatively high in this post-antibiotic era. Actually the prevalence of infection due to penicillin-resistant penumococci is increasing worldwide, and it is especially high in Korea due to irrelevant use of antibiotics. So, the high mortality of pneumococcal sepsis might be related to the emergence of penicillin-resistant strains, however, many other antibiotics, which eradicate pneumococci effectively, are available in these days. This has led us to suspect the role of penicillin-resistance in the high mortality rate. In this study, we evaluated the effect of penicillin resistance on the mortality of patients with penumococcal bacte remia. Methods: The study population consisted of 50 adult patients with penumococcal bacteremia who were admitted between Jan, 1990 and July, 1997. Medical records were analyzed retrospectively. Results: Most of the patients (96%) had underlying diseases. The most common local disease associated with pneumococcal bacteremia was pneumonia (42%), which was followed by spontaneous bacterial peritonitis (14%), cholangitis (10%), meningitis (8%), liver abscess (4%), pharyngotonsillitis (4%), sinusitis (2%) and cellulitis (2%). While the overall case-fatality rate in this study was 24%, it was higher when peumococcal bacteremia was associated with pneumonia (42%) or meningitis (50%). The rate of penicillin resistance was 40%, which was increased rapidly from 1991. The rate of penicillin resistance was significantly higher in patients with the history of recent antibiotics use and hospitalization within 3 months respectively. The clinical manifestations, that is, age, severity of underlying diseases, nosocomial infection, associated local diseases, and the presence of shock or acute renal failure were not statistically different between the patients with penicillin-resistant and -sensitive pneumococcal bacteremia. The mortality of patients infected with penicillin-resistant pneumococci was not statistically different from those with penicillin-sensitive pneumococcal bacteremia. Conclusion: Penicillin resistance is not associated with high mortality in adult patients with pneumococcal bacteremia. As the overall mortality is high, active penumococcal vaccination is recommended in patients with high risk of infection.

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