• Title/Summary/Keyword: Ventilation rate

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Properties of Light-weight Expanded Bonded Leather Using Thermal Expandable Microspheres (열 팽창성 Microsphere를 적용한 경량 발포 재생피혁 특성 분석)

  • Shin, Eun-Chul;Kim, Won-Ju;Kim, Yeong-Woo
    • Journal of Adhesion and Interface
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    • v.21 no.3
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    • pp.81-85
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    • 2020
  • Shaving dust is a collagen fiber that is the leather waste occurred for thickness adjustment during the natural leather manufacturing process, and causes problems such as an environmental contamination because of a chromium (Cr) contained when it comes to reclaiming process. Various studies applying the shaving dust are currently being conducted in many countries across the world with an initiative by the EU. Of those applications, the bonded leather is being highlighted as a substitute for natural leather. Since the bonded leather, however, uses latex as a binder, accordingly it entails a high weight and a poor ventilation, which are deemed as disadvantages due to its dense internal tissues compared to other synthetic leathers. To address such disadvantages, this study employed the thermally expandable micro sphere to improve its air permeability and light weight by alleviating the internal structure. This is a study on the manufacturing of light bonded leather using the shaving dusts. In the study, the shaving dusts were forced to foam under 100~120℃ considering the heat resistance of collagen fiber after applying the thermally expandable micro sphere, and then the tendency was analyzed. In the analysis results, the most excellent foaming rate was exhibited when the shaving dusts were treated under 120℃ for 8 minutes and the variation of internal structure according to a foaming was observed through SEM analysis for the cross-section of the bonded leather.

Clinical Characteristics of Patients with Neonicotinoid Insecticide Poisoning (Neonicotinoid 살충제 중독환자의 임상양상)

  • Kim, Jin-Chul;So, Byung-Hak;Kim, Han-Joon;Kim, Hyung-Min;Park, Jung-Ho;Choi, Se-Min;Park, Kyu-Nam;Choi, Kyoung-Ho
    • Journal of The Korean Society of Clinical Toxicology
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    • v.8 no.1
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    • pp.24-29
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    • 2010
  • Purpose: Neonicotinoid insecticides are widely used as they have been proven by experimental studies to have low toxicity to mammals, including humans. As the use of neonicotioids increases, the number of patients with neonicotinoid poisoning has also increased. We conducted a study to investigate the clinical manifestations of neonicotinid poisoning. Methods: We retrospectively analyzed the patients who ingested neonicotinids and who visited the emergency department located in Korea from March 2002 to February 2010. We reviewed the patients' age, gender, the amount of exposure, the elapsed time to presentation, the treatment and the outcome. According to the poisoning severity score, we divided the patients with a Poisoning severity score (PSS) of 0 or 1 into the mild/moderate toxicity group and the patients with a PSS of 2 or 3 into the severe/fatal toxicity group. Results: A total of 24 patients were analyzed. The most common clinical manifestations of neonicotinoid insecticide toxicity were gastrointestinal symptoms (66.7%) such as nausea, vomiting and abdominal pain and the others are respiratory symptoms (16.7%), cardiovascular symptoms (12.5%), metabolic imbalance (12.5%), renal dysfunction (8.3%), CNS symptoms (8.3%), and asymptomatic (29.2%). Twenty patients (83.3%) showed mild/moderate toxicity and 4 patients (16.7%) showed fatal conditions such as shock and mutiorgan failure. The mortality rate was 4.2%. In these fatal cases, the patients developed respiratory failure, hypotension, altered mentality and renal failure at the acute stage and they deteriorated to a more serious condition. This severe toxicity was caused by decreased renal excretion of neonicotinid metabolite, and this was improved after hemodialysis. Conclusion: Most patients with neonicotinoid poisoning and who showed mild toxicity usually improved after symptomatic treatment. However, some patients showed significant toxicity with respiratory failure and renal function deterioration, and intensive care needed, including mechanical ventilation and hemodialysis.

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Evaluation of the Farmers' Workload and Thermal Environments during Chili Harvest in the Open Field (여름철 노지 고추 수확 작업시 고령농업인의 온열 부담 평가)

  • Chae, Hyeseon;Kim, Hyunjin;Oh, Youngsoon;Lee, Kyungsuk;Kim, Hyocher;Kim, Kyungran
    • The Korean Journal of Community Living Science
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    • v.24 no.4
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    • pp.543-552
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    • 2013
  • Physiological and subjective responses of the farmers and thermal environment during chili harvest in the open field were investigated to evaluate the thermal environments and farmers's workload. Eight career female farmers in their sixties participated as subjects both in morning work(MW, AM 9:00~10:30) and in afternoon work(AW, PM 15:00~16:30) with each lasting about 90 minutes. The results were as follows. 1) Air temperature, air humidity, globe temperature and WBGT of MW were mean $25.54^{\circ}C$, 81.82%RH, $37.72^{\circ}C$, $26.27^{\circ}C$ and AW were mean $30.63^{\circ}C$ 82.50%RH, $40.11^{\circ}C$, $30.02^{\circ}C$, respectively. By the WBGT, we evaluated that the thermal environment in the afternoon in the open field gave a thermal burden to farmers. 2) Mean skin temperature of AW($34.8{\pm}0.8^{\circ}C$) was higher than MW($33.5{\pm}1.2^{\circ}C$)(p<0.05). Clothing microclimate temperature on the chest of each work time were $31.3^{\circ}C$(MW) and $32.7^{\circ}C$(AW). Clothing microclimate humidity on the chest of each work time were over 80%RH. Heart rate were 88.5bpm(MW) and 91.7bpm(AW) respectively. 3) Farmers working in the afternoon felt uncomfortable after 45~60 min. of work and in the morning they felt uncomfortable after 90 min. of work. We evaluated that the harvesting of chilies in the open field was 'moderate work' by the physiological responses but the level of thermal burden increased over time especially in the afternoon work. It is suggested that farm workers should drink fluids between work to stay in homeostasis by sweating and to take frequent rests. Active clothing ventilation and wearing functional garments would help farm workers excrete sweat effectively.

Recent research trends of post-harvest technology for king oyster mushroom (Pleurotus eryngii) (큰느타리버섯 수확후 관리기술 최근 연구 동향)

  • Choi, Ji-Weon;Yoon, YoeJin;Lee, Ji-Hyun;Kim, Chang-Kug;Hong, Yoon-Pyo;Shin, Il Sheob
    • Journal of Mushroom
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    • v.16 no.3
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    • pp.131-139
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    • 2018
  • The king oyster mushroom (Pleurotus eryngii) is widely consumed because of its flavor, texture, and its functional properties such as antioxidant activity and prebiotic effects. However, long-term product storage and transportation (e.g., export) are difficult because of its limited durability. The shelf-life of king oyster mushroom is affected by environmental factors such as temperature, humidity, gas composition, and ventilation, which may affect sensory characteristics including respiration rate, texture, moisture, flavor, color, and pH. The major problems regarding storage of mushrooms are browning, flavor changes, and softening. To address these problems, novel preservation techniques were developed, and more durable variants were bred. Different drying methods, gamma irradiation, chitosan coating, modified atmosphere (MA) packaging, and controlled atmosphere (CA) storage were evaluated in order to extend the shelf-life of king oyster mushrooms. Freeze drying showed better results for the preservation of mushrooms than other drying methods. Irradiation with 1 kGy was more effective for extending mushroom shelf-life than higher doses. The preservative performance of chitosan-based films was improved by combining the compound with other hydrocolloids, such as oil, protocatechuic acid, and wax. The CA storage conditions recommended for king oyster mushrooms are 5kPa $O_2$ and 10 to 15kPa $CO_2$ at temperatures below $10^{\circ}C$. Active MA packaging with microperforated PP film was also effective for maintaining quality during storage.

Evaluation of Odor Reduction in the Enclosed Pig Building Through Spraying Biological Additives (생물학적 첨가제 살포에 의한 밀폐형 돈사에서의 악취 저감 평가)

  • 김기연;최홍림;고한종;이용기;김치년
    • Journal of Animal Science and Technology
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    • v.48 no.3
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    • pp.467-478
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    • 2006
  • Maintenance of an optimal air quality in the enclosed pig building is potentially important in terms of pig performance and farmer health. The objective of this on-site experiment is to evaluate and compare efficiencies of currently utilized biological additives to reduce odor emissions from the enclosed pig building. As a result, generally all the additives except for salt water, artificial spice and essential oil were proved ineffective in reducing odor generation. The beneficial effects of salt water, artificial spice and essential oil on odor reduction were highlighted on ammonia, odor intensity and offensiveness, and sulfuric odorous compounds, respectively. To efficiently utilize odor masking agent such as the artificial spice, ventilation rate should keep slightly lower than the optimal level. Essential oil functioned well as not only masking agent but also antimicrobial agent for reducing odor. To precisely quantify odor concentration, it should be measured by not the odor sensor but the olfactometry technique.

The efficacy and safety of Montelukast sodium in the prevention of bronchopulmonary dysplasia

  • Kim, Sang Bum;Lee, Jang Hoon;Lee, Juyoung;Shin, Seung Han;Eun, Ho Sun;Lee, Soon Min;Sohn, Jin A;Kim, Han Suk;Choi, Byung Min;Park, Min Soo;Park, Kook In;Namgung, Ran;Park, Moon Sung
    • Clinical and Experimental Pediatrics
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    • v.58 no.9
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    • pp.347-353
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    • 2015
  • Purpose: The purpose of this study was to evaluate the efficacy and safety of Montelukast sodium in the prevention of bronchopulmonarydysplasia (BPD). Methods: The Interventional study was designed as a multicenter, prospective, and randomized trial, with open labeled and parallel-experimental groups, 66 infants were enrolled and allocated to either the case group (n=30) or the control group (n=36) based on gestational age (GA). Infants in the case group were given Montelukast sodium (Singulair) based on their body weight (BW). Zero week was defined as the start time of the study. Results: The incidence of moderate to severe BPD was not different between the groups (case group: 13 of 30 [43.3%] vs. control group: 19 of 36 [52.8%], P=0.912). Additionally, secondary outcomes such as ventilation index, mean airway pressure and resort to systemic steroids were not significantly different. There were no serious adverse drug reactions in either group, and furthermore the rate of occurrence of mild drug related-events were not significantly different (case group: 10 of 42 [23.8%] vs. control group: 6 of 48 (15.8%), P=0.414). Conclusion: Montelukast was not effective in reducing moderate or severe BPD. There were no significant adverse drug events associated with Montelukast treatment.

Venovenous Extracorporeal Membrane Oxygenation for Postoperative Acute Respiratory Distress Syndrome

  • Seo, Dong Ju;Yoo, Jae Suk;Kim, Joon Bum;Jung, Sung-Ho;Choo, Suk Jung;Chung, Cheol Hyun;Lee, Jae Won
    • Journal of Chest Surgery
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    • v.48 no.3
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    • pp.180-186
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    • 2015
  • Background: Extracorporeal membrane oxygenation (ECMO) has recently attracted interest as a treatment for severe acute respiratory distress syndrome (ARDS). However, the outcomes of this procedure in post-surgical settings have not yet been characterized. In this study, we evaluated the outcomes of ECMO in patients with severe postoperative ARDS. Methods: From January 2007 to December 2012, a total of 69 patients (aged $58.3{\pm}11.5$ years, 23 females) who underwent venovenous ECMO to treat severe postoperative ARDS were reviewed. Of these patients, 22 (31.9%) had undergone cardiothoracic surgery, 32 (46.4%) had undergone liver transplantation, and 15 (21.7%) had undergone other procedures. Results: Thirty-four patients (49.3%) were successfully weaned from ECMO, while the other 35 patients (50.7%) died on ECMO support. Among the 34 patients who were successfully weaned from ECMO, 21 patients (30.4%) eventually died before discharge from the hospital, resulting in 13 hospital survivors (18.8%). Multivariable analysis showed that the duration of pre-ECMO ventilation was a significant independent predictor of death (odds ratio [OR], 2.25; 95% confidence interval [CI], 1.29 to 3.90; p=0.004), whereas the concomitant use of continuous venovenous hemodialysis (CVVHD) was associated with improved survival (OR, 0.55; 95% CI, 0.31 to 0.97; p=0.038). Conclusion: Although the overall survival rate of patients treated with ECMO for postoperative ARDS was unfavorable, ECMO offered an invaluable opportunity for survival to patients who would not have been expected to survive using conventional therapy. CVVHD may be beneficial in improving the outcomes of such patients, whereas a prolonged duration of pre-ECMO ventilator support was associated with poor survival.

Method for Preventing Asphyxiation Accidents by a CO2 Extinguishing System on a Ship (선박 내 CO2 소화설비에 의한 질식사고 방지 기법)

  • Ha, Yeon-Chul;Seo, Jung-Kwan;Hwang, Jun-Ho;Im, Kichang;Ryu, Sang-Hoon
    • Fire Science and Engineering
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    • v.29 no.6
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    • pp.57-64
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    • 2015
  • Carbon dioxide extinguishing systems are broadly used for onshore and offshore fire accidents because of excellent performance and low cost. However, there is risk with carbon dioxide systems, which have caused many injuries and deaths by suffocation associated with industrial and marine fire protection applications. In this study, a numerical analysis was performed to predict the fire suppression characteristics of a carbon dioxide system in the compressor room of ships. A double protection safety system is suggested to prevent suffocation accidents from carbon dioxide extinguishing systems. Four scenarios were selected to study the variation of the heat release rate, maximum temperature, a $CO_2$ and $O_2$ mole fraction, and fire suppression characteristics with the carbon dioxide system. The importance of proper design is suggested for a ventilation system in the compressor room of ships.

Case of the Pulmonary Thromboembolism in a Patient with Lacunar Cerebral Infarction by the Integrated Therapy of Korean and Western Medicine (열공성 뇌경색 환자에게 발생한 폐색전증을 한양방 협진으로 치료한 1례)

  • Yun Jong-Min;Lee Min-Goo;Lee Sun-Woo;Kang Baek-Gyu;Lee Seung-Eon;Kim Yong-Jeong;Son Ji-Woo;Lee In;Moon Byung-Soon;Park Sae-Wook
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.6
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    • pp.1676-1680
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    • 2005
  • There are few topic about a pulmonary thromboembolism(PTE) especially in Korean medical research. This case report is dealt with a rare situation that a PTE and a lacunar infarction are complicated in one patient. They have a similarity in that both are caused by the thrombosis. The former is the thrombosis in lung and the latter is the cerebral infarcion within the territory of a single perforating artery Recently the attack rate of PTE somewhat grow because of the development of medicine such as the increasing use of indwelling catheters, trauma or surgery of pelvis and lower extrimity, major surgery especially in senior, the use of estrogen containing compounds, cerebrovascular disease, obesity, etc. A 70 year-old lady was stroked by the cerebral infarction and has been getting rehabilitating therapy. She had the sudden onset of dyspnea, chest pain and those symptoms looked like a myocardial infarction. But she was diagnosed as PTE by ventilation perfusion lung scan. We cured her with the integrated therapy of Korean and Western medicine.

The Early Results of CABG with Bilateral Internal Thoracic Artery (양측 내흉동맥을 이용한 관상동맥우회술의 조기 결과)

  • 조광현;최강주;김경현;전희재;윤영철;이양행;황윤호
    • Journal of Chest Surgery
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    • v.36 no.5
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    • pp.303-308
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    • 2003
  • Background: It has been known that internal thoracic artery grafting has a better patency rate compare to other graft conduits in coronary revascularization. Better patency rates can be expected in more coronary arteries with the use of bilateral internal thoracic artery. However, there were some debates on the complications after the use of bilateral internal thoracic artery. The purpose of our study was to reveal the results of bilateral internal thoracic artery. Material and Method: The 26 coronary artery bypass operations with bilateral internal thoracic artery were performed from July 2001 to May 2002. We compared the results of 8 diabetic patients to those of 18 non-diabetic patients. We compared the results of BITA (bilateral internal thoracic artery) group to those of SITA (single internal thoracic artery) group that were 20 patients and performed during same period. Result: There was no mortality. There was one wound complication in the diabetic group and one in the non-diabetic group. There were no significant differences in operation time, duration of mechanical ventilation, amount of bleeding, infusing duration of cardiotonics, and complication between two groups. There were no significant differences in results between the BITA group and the SITA group. Conclusion: There were no significant differences in early results between the BITA group and the SITA group, and there were no significant differences in results between the diabetic group and the non-diabetic group. We think coronary artery bypass grafting with the use of bilateral internal thoracic artery is considered in diabetic patients.