• Title/Summary/Keyword: Reduction rates

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Effect of Calcium Chloride (CaCl2) on the Characteristics of Photosynthetic Apparatus, Stomatal Conductance, and Fluorescence Image of the Leaves of Cornus kousa (염화칼슘 처리가 산딸나무 잎의 광합성 기구, 기공전도도 및 형광이미지 특성에 미치는 영향)

  • Sung, Joo-Han;Je, Sun-Mi;Kim, Sun-Hee;Kim, Young-Kul
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.4
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    • pp.143-150
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    • 2009
  • Deicing salt is used to melt snow and ice on the road for traffic safety during the winter season, which accumulates in the roadside vegetation and induces visible injuries. The damage may accelerate particularly when it coincides with early spring leaf out. In order to better understand the response mechanisms, C. kousa (3-year-old) was irrigated twice prior to leaf bud in a rhizosphere with solutions of 0.5, 1.0, and 3.0% calcium chloride ($CaCl_2$) concentration, that were made by using an industrial $CaCl_2$ reagent practical deicing material in Seoul. Physiological traits of the mature leaves were progressively reduced by $CaCl_2$ treatment, resulting in reductions of total chlorophyll contents, chlorophyll a:b, photosynthetic rate, quantum yield, stomatal conductance, $F_V/F_M$, and NPQ. On the contrary, light compensation point and dark respiration were increased at high $CaCl_2$ concentration. A decrease in intercellular $CO_2$ concentration by stomatal closure first resulted in a reduced photosynthetic rate and then was accompanied by low substance metabolic rates and photochemical damage. Based on the reduction of physiological activities at all treatments ($CaCl_2$ 0.5%, 1.0%, and 3.0%), C. kousa was determined as one of the sensitive species to $CaCl_2$.

Analysis of Image Factors of X-ray Films: Study for the Intelligent Replenishment System of Automatic Film Processor (자동현상기 지능화에 필요한 연산처리 기법의 개발을 위한 방사선 필름의 영상 지수의 분석)

  • Park, Sung-Tae;Yoon, Chong-Hyun;Park, Kwang-Bo;Auh, Yong-Ho;Lee, Hyoung-Jin;In, Kyung-Hwan;Kim, Keon-Chung
    • Journal of radiological science and technology
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    • v.21 no.1
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    • pp.35-39
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    • 1998
  • We analyzed image factors to determine the characteristic factors that need for intelligent replenishment system of the auto film processor. We processed the serial 300 sheets of radiographic films of chest phantom without replenishment of developing and fixation replenisher. We took the digital data by using film digitizer which scaned the films and automatically summed up the pixel values of the films. We analyzed characteristic curves, average gradients and relative speeds of individual film using densitometer and step densitometry. We also evaluated the pH of developer, fixer, and washer fluid with digital pH meter. Fixer residual rate and washing effect were measured by densitometer using the reagent methods. There was no significant reduction of the digital density numbers of the serial films without replenishment of developer and fixer. The average gradients were gradually decreased by 0.02 and relative speeds were also gradually decreased by 6.96% relative to initial standard step-densitometric measurement. The pHs of developer and fixer were reflected the inactivation of each fluid. The fixer residual rates and washing effects after processing each 25 sheets of films were in the normal range. We suggest that the digital data are not reliable due to limitation of the hardware and software of the film digitizer. We conclude that average gradient and relative speed which mean the film's contrast and sensitivity respectively are reliable factors for determining the need for the replenishment of the auto film processor. We need more study of simpler equations and programming for more intelligent replenishment system of the auto film processor.

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A Study on Dose Distribution around Fletcher-Suit Colpostat Containing Cs-137 Source by a Computer (컴퓨터 의한 Fletcher-Suit Colpostat 주변의 Cs-137의 선량분포에 관한 연구)

  • Kang Wee-Saing
    • Radiation Oncology Journal
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    • v.7 no.2
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    • pp.305-311
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    • 1989
  • Fletcher-Suit colpostat has an internal structure to reduce dose to bladder and rectum. Some programs were developed to calculate dose at any point in water in three dimension around the colpostat containing Cs-137 tube, to find the shielding effect to dose by the internal structure, and to draw isodose curves and iso-shielding effect curves. Computer was an IBM compatible AT with EGA card and language was MS-Basic V6.0, Material, shape and geometry of the strucure, tube and colpostat were considered in algorithm for calculation of dose. Dose rates per unit mg. Ra. eq. in water calculated by a program were stored in auxiliary memory devices and retrieved in another programs. Isodose curves on medial side shrinked. Dose distribution was not symmetric about a transverse axis bisecting the colpostat. Reduction of dose was more excessive on top side than on bottom. Iso-shielding effect curve showed that the shielding effect was higher on top side than on bottom, and that there was shielding effect over almost all area of medial side. Such results were related to both shifted position of tube in the colpostat and asymmetric distribution of active source in the tube. Maximum of shielding effect was $49\%$ on top side and $44\%$ on bottom side. The direction of iso-shielding effect curve was generally radial from the center of active source. In treatment planning using Fletcher-Suit colpostat, the internal structure should be considered to find precise doses to bladder and rectum, etc.

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Characteristics of $Al_2O_3/TiO_2$ multi-layers as moisture permeation barriers deposited on PES substrates using ECR-ALD

  • Gwon, Tae-Seok;Mun, Yeon-Geon;Kim, Ung-Seon;Mun, Dae-Yong;Kim, Gyeong-Taek;Park, Jong-Wan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.457-457
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    • 2010
  • Flexible organic light emitting diodes (F-OLEDs) requires excellent moisture permeation barriers to minimize the degradation of the F-OLEDs device. Specifically, F-OLEDs device need a barrier layer that transmits less than $10^{-6}g/m^2/day$ of water and $10^{-5}g/m^2/day$ of oxygen. To increase the life time of F-OLEDs, therefore, it is indispensable to protect the organic materials from water and oxygen. Severe groups have reported on multi-layerd barriers consisting inorganic thin films deposited by plasma enhenced chemical deposition (PECVD) or sputtering. However, it is difficult to control the formation of granular-type morphology and microscopic pinholes in PECVD and sputtering. On the contrary, atomic layer deoposition (ALD) is free of pinhole, highly uniform, conformal films and show good step coverage. Thus, $Al_2O_3/TiO_2$ multi-layer was deposited onto the polyethersulfon (PES) substrate by electron cyclotron resonance atomic layer deposition (ECR-ALD), and the water vapor transmission rates (WVTR) were measured. WVTR of moisture permeation barriers is dependent upon density of films and initial state of polymer surface. A significant reduction of WVTR was achieved by increasing density of films and by applying low plasma induced interlayer on the PES substrate. In order to minimize damage of polymer surface, a 10 nm thick $TiO_2$ was deposited on PES prior to a $Al_2O_3$ ECR-ALD process. High quality barriers were developed from $Al_2O_3$ barriers on the $TiO_2$ interlayer. WVTR of $Al_2O_3$ by introducing $TiO_2$ interlayer was recorded in the range of $10^{-3}g/m^2.day$ at $38^{\circ}C$ and 100% relative humidity using a MOCON instrument. The WVTR was two orders of magnitude smaller than $Al_2O_3$ barriers directly grown on PES substrate without the $TiO_2$ interlayer. Thus, we can consider that the $Al_2O_3/TiO_2$ multi-layer passivation can be one of the most suitable F-OLEDs passivation films.

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Butachlor and 1,8- Nphthalic Anhydride Effects on Post - Germination Growth, Anatomy and Root - Cell Membrane Permeability of Rice (벼의 발아후(發芽後) 생육(生育), 세포형태(細胞形態) 및 근세포막(筋細胞膜) 투과성(透過性)에 미치는 BUTACHLOR 와 1,8-NAPHTHALIC ANHYDRIDE 의 영향(影響))

  • Chun, J.C.;Hwang, I.T.;Han, M.S.
    • Korean Journal of Weed Science
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    • v.5 no.1
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    • pp.56-62
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    • 1985
  • Effects of butachlor [N-(butoxymethyl)-2-chloro-2', 6'-diethyl acetanilide] and 1,8-naphthalic anhydride (NA) on post-germination growth, mesocotyl and root anatomy and root-cell membrane permeability of rice (Orvza saliva L.) were investigated. Lengths of mesocotyl and radicle were markedly decreased as the application rates of butachlor increased from 0.1 to 100 ppmW and NA from 1 to 100 ppmW, but there was no effect on coleoptile elongation. Application of butachlor-NA resulted in increase in coleoptile elongation, but decrease in mesocotyl elongation. Partial breakdown of cortical cells in root and mesocotyl was caused by either trutachlor or NA treatments, resulting in increase in intercellular air space. Further increase in the intercellular air space of root and mesocotyl was obtained when butachlor was applied in combination with NA. Increase in root-cell membrane permeability occurred when either butachlor or NA was applied. However, butachlor-NA treatments resulted in reduction in the permeability.

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Establishment of Control System of Weedy Rice(Oryza sativa) and Barnyardgrass(Echinochloa crus-galli) in Direct-seeded Rice - I. Effect of Oxadiazon, Molinate, Thiobencarb on Control of Red Rice and Barnyardgrass in Water-seeded Rice (벼 직파재배에 있어서 잡초성벼 및 피 방제체계 확립에 관한 연구 - I. 담수표면산파 재배시 앵미와 피에 대한 oxadiazon, molinate, thiobencarb의 파종전 처리 효과)

  • Ryang, H.S.;Kim, J.K.;Kyoung, E.S.;Kim, J.S.;Ma, S.Y.
    • Korean Journal of Weed Science
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    • v.18 no.2
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    • pp.106-115
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    • 1998
  • This study was conducted to investigate the effect of oxadiazon, molinate, thiobencarb before seeding on control of red rice and barnyardgrass in water-seeded rice. High application rate plot among oxadiazon treatment plots could observe phytotoxicity symptoms depending on field conditions, but these injury recovered gradually with time. Molinate and thiobencarb application plots at the concentration of 225~400, 210~420g ai/l0a respectively were not observed phytotoxicity. Control of red rice was different according to kinds of herbicides and application rates. Oxadiazon showed higher control performance at the concentration of more than 60g ai/10a. Control effect of molinate and thiobencarb against red rice was enhanced with the increase of application rate, and both herbicides showed satisfactory effect at more than 300g ai/10a. Control of barnyardgrass showed up to 90~100% in all tested herbicides. There was no significant yield reduction by oxadiazon, molinate, and thiobencarb application before seeding in all tested field. In the pot experiment, crop injury, seedling stand, and early growth were more advantageous at time of drainge after one day after seeding than flooding until rooting.

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The fabrication and evaluation of CdS sensor for diagnostic x-ray detector application (진단 X선 검출기 적용을 위한 CdS 센서 제작 및 성능 평가)

  • Park, Ji-Koon;Lee, Mi-Hyun;Choi, Young-Zoon;Jung, Bong-Zae;Choi, Il-Hong;Kang, Sang-Sik
    • Journal of the Korean Society of Radiology
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    • v.4 no.2
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    • pp.21-25
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    • 2010
  • Recently, various semiconductor compounds as radiation detection material have been researched for a diagnostic x-ray detector application. In this paper, we have fabricated the CdS detecton sensor that has good photosensitivity and high x-ray absorption efficiency among other semiconductor compounds, and evaluated the application feasibility by investigating the detection properties about energy range of diagnostic x-ray generator. We have fabricated the line voltage selector(LCV) for a signal acquisition and quantities of CdS sensor, and designed the voltage detection circuit and rectifying circuit. Also, we have used a relative relation algorithm according to x-ray exposure condition, and fabricated the interface board with DAC controller. Performance evaluation was investigated by data processing using ANOVA program from voltage profile characteristics according to resistive change obtained by a tube voltage, tube current, and exposure time that is a exposure condition of x-ray generator. From experimental results, an error rates were reduced according to increasing of a tube voltage and tube current, and a good properties of 6%(at 90 kVp) and 0.4%(at 320 mA) ere showed. and coefficient of determination was 0.98 with relative relation of 1:1. The error rate according to x-ray exposure time showed exponential reduction because of delayed response velocity of CdS material, and the error rate has 2.3% at 320 msec. Finally, the error rate according to x-ray dose is below 10%, and a high relative relation was showed with coefficient of determination of 0.9898.

Meta-analysis of the Korean Literatures for Developing Clinical Practice Guidelines of Benign Prostatic Hyperplasia (전립선비대증의 진료지침 개발을 위한 한국문헌의 메타분석)

  • Yu, Seung-Hum;Kim, Chun-Bae;Kang, Myung-Geun;Song, Jae-Mann
    • Journal of Preventive Medicine and Public Health
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    • v.30 no.3 s.58
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    • pp.643-664
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    • 1997
  • This study is to provide evidence-based recommendations for the most-effective treatments of benign prostatic hyperplasia based on patient preference or clinical need, and to meta-analyze the Korean literatures for the development of BPH treatment guidelines. For these analyses, extensive literature searches (208 articles), with priority given to the Korean Journal of Urology, were conducted from 1960 to August, 1996. Meta-analysis, like all statistical analysis, has two main functions: data summarization (qualitative meta-analysis) and smoothing o. pattern recognition (quantitative meta-analysis). As well, critical reviews and syntheses with the mean and 90-percent confidence intervals for the likelihood were used to evaluate empirical evidence and significant outcomes of the BPH treatment literatures (106 articles). For this task, the Methodologic Panel for BPH Guidelines was composed of multidisciplinary experts in the field. The results of the study were summarized as follows: For all that watchful waiting is an appropriate treatment strategy for the majority of patients with prostatism, we couldn't find the Korean literatures which carried this article. The literatures on alpha-1-adrenergic receptor blockers provide no evidence to suggest that any one alpha blocker is more effective than another. The finasteride reduces the size of the prostate, on average, and leads to a small yet perceptible reduction in sysptoms. Of all treatment options, prostate surgery with transurethral resection of the prostate (TURP), transurethral incision of the prostate (TUIP), and so on, offers the best chance for symptom improvement. However, surgery also has the highest rates of significant complications. Therefore, surgery need not always be a treatment of last resort. Balloon dilation of the prostatic urethra is clearly less effective than surgery in relieving symptoms, but it is associated with fewer complications. Emerging technologies for treating BPH include lasers, coils, stents, thermal therapy and hyperthermia. Established technologies will also be reanalyzed as results of new trials are reported. Although this study has some limitations due to lacking for good quality literatures, ' it provides a cornerstone for our medical research. It represents the most current scientific knowledge regarding the clinical epidemiology including treatment of BPH. It will be revised and updated as needed.

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Association Between Prophylactic Antibiotic Use and Surgical Site Infection Based on Quality Assessment Data in Korea (요양급여적정성 평가자료를 이용한 예방적 항생제 사용과 수술부위 감염 발생의 관련성 연구)

  • Kim, Kyoung-Hoon;Park, Choon-Seon;Chang, Jin-Hee;Kim, Nam-Soon;Lee, Jin-Seo;Choi, Bo-Ram;Lee, Byung-Ran;Lee, Kyoo-Duck;Kim, Sun-Min;Yeom, Seon-A
    • Journal of Preventive Medicine and Public Health
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    • v.43 no.3
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    • pp.235-244
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    • 2010
  • Objectives: To examine the prophylactic antibiotic use in reducing surgical site infection. Methods: This was a retrospective study for patients aged 18 years and older who underwent gastrectomy, cholecystectomy, colectomy, cesarean section and hysterectomy. The data source was quality assessment data of the Health Insurance Review & Assessment Service gathered from medical records of 302 national hospitals. Prophylactic antibiotic use was defined as: timely antibiotic administration or inappropriate antibiotic selection. We performed hierarchical logistic regression to examine the association between prophylactic antibiotic use and surgical site infection with adjustment for covariates. Results: The study population consisted of 16 348 patients (1588 gastrectomies, 2327 cholecystectomies, 1,384 colectomies, 3977 hysterectomies and 7072 cesarean sections) and surgical site infection was identified in 351 (2.1%) patients. The rates of timely antibiotic administration and inappropriate antibiotic selection varied according to procedures. Cholecystectomy patients who received timely prophylactic antibiotic had a significantly reduced risk of surgical site infection compared with those who did not receive a timely prophylactic antibiotics (OR 0.64, 95% CI=0.50-0.83), but no significant reduction was observed for other procedures. When inappropriate prophylactic antibiotics were given, the risk of surgical site infection significantly increased: 8.26-fold (95% CI=4.34-15.7) for gastrectomy, 4.73-fold (95% CI=2.09-10.7) for colectomy, 2.34-fold (95% CI=1.14-4.80) for cesarean section, 4.03-fold (95% CI=1.93-8.42) for hysterectomy. Conclusions: This study examines the association among timely antibiotic administration, inappropriate antibiotic selection and surgical site infection. Patients who received timely and appropriate antibiotics had a decreased risk of surgical site infection. Efforts to improve the timing of antibiotic administration and use of appropriate antibiotic are needed to lower the risk of surgical site infection.

Isolation of Major foodborne Pathogenic Bacteria from Ready-to-Eat Seafoods and Its Reduction Strategy (해산물식품 중 식중독원인균의 오염패턴 및 저감화 방안)

  • KIM Soon Han;Sin Yeong-Min;Lee Myeong Ja;Shin Pil Ki;Kim Mi Cyeong;Cho Jung Sook;Lee Chang Hee;Lee Young Ja;Chae Kab Ryoung
    • Journal of Life Science
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    • v.15 no.6 s.73
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    • pp.941-947
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    • 2005
  • The contamination frequency of major foodborne pathogenic bacteria was investigated from 213 seafood samples including sliced raw fish and shellfish in Busan and CyeongNam province area. Tested microorganisms were Salmonella spp. Staphyloroccus aureus, Vibrio parahaemolyticus, Escherichia coli O157:H7, Bncillus cereus, Listeria monocytogenes and Campylobacter jejuni. The frequency of isolated microorganisms was V. parahaemolyticus (30.5%), B. cereus (9.9%), S. aureus (3.8%) and other pathogenic bacteria (1.4%). from July to October, total isolation rates were greater than 50% and V. parahaemolyticus was dominant among the microorganisms isolated. The bacteria isolation rate (49.2%) in raw seafoods including shellfishes was higher than one (28.9%) in sliced raw fish. V. parahaemelyticus isolates were resistant to ampicillin (96.9%), amikacin (29.2%) and tetracycline (27.7%), and B. cereus isolates were resistant to ampicillin (100%), Penicillin G (100%), rifampicin (71.4%) and tetracycline (14.3%). The growth of V. parahaemolyticus and B. rereus was greatly inhibited below $10^{\circ}C$, but increased at ambient temperature. Washing seafood with tap water showed to reduce total count of remaining V. parahaemolyticus. Thus temperature control under $10^{\circ}C$, sufficient washing and prompt eating appeared to reduce the risk of food poisoning by these bacteria in seafoods.