• Title/Summary/Keyword: volume effects

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The Benefit of Individualized Custom Bolus in the Postmastectomy Radiation Therapy : Numerical Analysis with 3-D Treatment Planning (유방전절제술 후 방사선치료를 위한 조직보상체 개발 및 3차원 치료계획을 통한 유용성 분석)

  • Cho Jae Ho;Cho Kwang Hwan;Keum Kichang;Han Yongyih;Kim Yong Bae;Chu Sung Sil;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.21 no.1
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    • pp.82-93
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    • 2003
  • Purpose : To reduce the Irradiation dose to the lungs and heart in the case of chest wail irradiation using an oppositional electron beam, we used an Individualized custom bolus, which was precisely designed to compensate for the differences In chest wall thickness. The benefits were evaluated by comparing the normal tissue complication probablilties (NTCPS) and dose statistics both with and without boluses. Materials and Methods : Boluses were made, and their effects evaluated in ten patients treated using the reverse hockey-stick technique. The electron beam energy was determined so as to administer 80% of the irradiation prescription dose to the deepest lung-chest wall border, which was usually located at the internal mammary lymph node chain. An individualized custom bolus was prepared to compensate for a chest wall thinner than the prescription depth by meticulously measuring the chest wall thickness at 1 emf intervals on the planning CT Images. A second planning CT was obtained overlying the individuailzed custom bolus for each patient's chest wall. 3-D treatment planning was peformed using ADAC-Pinnacle$^{3}$ for all patients with and without bolus. NTCPS based on 'the Lyman-Kutcher' model were analyzed and the mean, maximum, minimum doses, V$_{50}$ and V$_{95}$ for 4he heari and lungs were computed. Results .The average NTCPS in the ipsliateral lung showed a statistically significant reduction (p<0.01), from 80.2${\pm}$3.43% to 47.7${\pm}$4.61%, with the use of the individualized custom boluses. The mean lung irradiation dose to the ipsilateral iung was also significantly reduced by about 430 cGy, Trom 2757 cGy to 2,327 cGy (p<0.01). The V$_{50}$ and V$_{95}$ in the ipsilateral lung markedly decreased from the averages of 54.5 and 17.4% to 45.3 and 11.0%, respectively. The V$_{50}$ and V$_{95}$ In the heart also decreased from the averages of 16.8 and 6.1% to 9.8% and 2.2%, respectively. The NTCP In the contralateral lung and the heart were 0%, even for the cases with no bolus because of the small effective mean radiation volume values of 4.4 and 7.1%, respectively Conclusion : The use of an Individualized custom bolus in the radiotherapy of postrnastectorny chest wall reduced the NTCP of the ipsilateral lung by about 24.5 to 40.5%, which can improve the complication free cure probability of breast cancer patients.

The Effect of Deep Breathing Methods on Pulmonary Ventilatory Function of Patients Who experiened Upper-abdominal surgery (심호흡 방법에 따른 상복부 수술환자의 폐 환기능에 미치는 효과)

  • Hwang Jin-Hee;Park Hyung-Suk
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.1 no.2
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    • pp.129-147
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    • 1994
  • The purpose of this study was to examine the effect of deep breathing exercise with Incentive Spirometer on the pulmonary ventilatory function of postoperative patients. This experiment was operated by quasi-experimental design which was compared pre-experimental measures with post-experimental ones. The subject of this study was 46 inpatients who were scheduled for elective upper abdominal surgery under the general anesthesia in P National University Hospital in Pusan and classified into the experimental group(23 patients) and control group(23 patients) by using Incentive Spirometer or unusing one. The data were collected from November, 1, 1993, to December, 31, 1993. The effects of the deep breathing exercise on the pulmonary ventilatory function were compared between experimental group who were recieved deep breathing exercise with Incentive Spirometer and control group who were recieved same method without Incentive Spirometer. The Forced Vital Capacity (FVC) and the First Second Forced Expiratory Volume ($FEV_1$) were represented as index of the pulmonary ventilatory function and those were measured by Vitalograph Compact. The collected data were analysed by SPSS/PC+ (percentage, average, standard deviation, chi-square test, t-test, and ANOVA). The results were as follow : (1) The $FVC_s$ of the experimental group were significantly increased in course of time, 24, 48, 72 hours after surgery(F=3.530, P=0.035). (2) The $FVC_s$ and $FEV_{1S}$ of the control group were significantly increased in course of time, 24, 48, 72 hours after surgery ($FVC_s$ : F=3.480, P=0.037, $FEV_{1S}$ : F=6. 153, P=0.004). (3) The FVC which was measured at 72 hours after surgery was significantly higher in the experimental group than in the control group(t=2.620, P=0.013). (4) The $FEV_{1s}$ which were measured at 24 and 72 hours after surgery were significantly higher in the experimental group than in the control group(24hr. : t=2.530, P=0.017, 72hr. : t=2.540, P=0.016). (5) Among general characteristics, sex was significant variable which influenced to effect of pulmonary ventilatory function. In conclusion, this study showed that the deep breathing exercise with Incentive Spirometer was more effective to recover the pulmonary ventilatory function after surgery than the deep breathing exercise without Incentive Spirometer.

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Dosimetric Effect on Selectable Optimization Parameters of Volumatric Modulated Arc Therapy (선택적 최적화 변수(Selectable Optimization Parameters)에 따른 부피적조절회전방사선치료(VMAT)의 선량학적 영향)

  • Jung, Jae-Yong;Shin, Yong-Joo;Sohn, Seung-Chang;Kim, Yeon-Rae;Min, Jung-Wan;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.23 no.1
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    • pp.15-25
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    • 2012
  • The aim of this study is to evaluate plan quality and dose accuracy for Volumetric Modulated Arc Therapy (VMAT) on the TG-119 and is to investigate the effects on variation of the selectable optimization parameters of VMAT. VMAT treatment planning was implemented on a Varian iX linear accelerator with ARIA record and verify system (Varian Mecical System Palo Alto, CA) and Oncentra MasterPlan treatment planning system (Nucletron BV, Veenendaal, Netherlands). Plan quality and dosimetric accuracy were evaluated by effect of varying a number of arc, gantry spacing and delivery time for the test geometries provided in TG-119. Plan quality for the target and OAR was evaluated by the mean value and the standard deviation of the Dose Volume Histograms (DVHs). The ionization chamber and $Delta^{4PT}$ bi-planar diode array were used for the dose evaluation. For treatment planning evaluation, all structure sets closed to the goals in the case of single arc, except for the C-shape (hard), and all structure sets achieved the goals in the case of dual arc, except for C-shape (hard). For the variation of a number of arc, the simple structure such as a prostate did not have the difference between single arc and dual arc, whereas the complex structure such as a head and neck showed a superior result in the case of dual arc. The dose distribution with gantry spacing of $4^{\circ}$ was shown better plan quality than the gantry spacing of $6^{\circ}$, but was similar results compared with gantry spacing of $2^{\circ}$. For the verification of dose accuracy with single arc and dual arc, the mean value of a relative error between measured and calculated value were within 3% and 4% for point dose and confidence limit values, respectively. For the verification on dose accuracy with the gantry intervals of $2^{\circ}$, $4^{\circ}$ and $6^{\circ}$, the mean values of relative error were within 3% and 5% for point dose and confidence limit values, respectively. In the verification of dose distribution with $Delta^{4PT}$ bi-planar diode array, gamma passing rate was $98.72{\pm}1.52%$ and $98.3{\pm}1.5%$ for single arc and dual arc, respectively. The confidence limit values were within 4%. The smaller the gantry spacing, the more accuracy results were shown. In this study, we performed the VMAT QA based on TG-119 procedure, and demonstrated that all structure sets were satisfied with acceptance criteria. And also, the results for the selective optimization variables informed the importance of selection for the suitable variables according to the clinical cases.

The Mechanism of Interferon-$\gamma$ Induced Cytotoxicity on the Lung Cancer Cell Line, A549 (인터페론감마에 의한 A549 폐암세포주 세포독성의 기전)

  • Oh, Yeon-Mok;Yoo, Chul-Gyu;Chung, Hee-Soon;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.1
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    • pp.63-68
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    • 1996
  • Background: Interferon-$\gamma$ has various biologic effects, including antiviral effect, antitumor proliferative effect, activation of macrophage and B lymphocyte, and increased expression of major histocompatibility complex. Especially, antitumor proliferative effect of interferon-$\gamma$ has already been proved to be important in vivo as well as in vitro. And, clinical studies of interferon-$\gamma$ have been tried in lung cancer patients. However, the mechanism of antitumor effect of interferon-$\gamma$ has not yet been established despite of many hypotheses. "Necrosis" is a type of cell death which is well known to occur in the circumstances of severe stresses. In contrast, "apoptosis" is another type of cell death which occurs in such biological circumstances as embryonic development, regression of organs, and self-tolerance of lymphocytes. And, apoptosis is an active process of cell death in which cells are dying with fragmentations of their cytoplasms and nuclei. And, in the process of apoptosis the DNAs of cells are cleaved between nucleosomes by unidentified endonuclease and therefore DNAs of apoptotic cells result in a typical electrophoresis pattern known as DNA ladder pattern. Recently it has been suggested that cytotoxic effect of interferon-$\gamma$ occurs via apoptosis. To elucidate the mechanism of antitumor cytotoxic effect of interferon-$\gamma$, we microscopically observed a lung cancer cell line, A549 which was treated with interferon-$\gamma$. We observed A545 treated with interferon-$\gamma$ was dying fragmented. And so, we performed this study to find out that the mechanism of antitumor cytotoxic effect of interferon-$\gamma$ be apoptosis. Method: We treated A549, human lung cancer cell line with various concentration of interferon-$\gamma$ and quantified its cytotoxic effect of various periods, 24 hours, 72 hours and, 120 hours by MTT(dimethylthiazolyl diphenyltetrazolium bromide) bioassay. Also, after we treated A549 with 100 units/mi of interferon-$\gamma$ for 120 hours, we observed the pattern of cell death with inverted microscope and we extracted DNAs from the dead A549 cells and observed the pattern of 1.5% agarose gel electrophoresis with ethidium bromide staining. Result: 1) Cytotoxic effect of interferon-$\gamma$ on A549: For the first 24 hours, threre was little cytotoxic effect and for between 24 hours and 72 hours, there was the beginning of cytotoxic effect and for 120 hours there was increased cytotoxic effect. 2) Pattern of A549 cell death by interferon-$\gamma$: We observed with inverted microscope that A549 cells were dying fragmented. 3) DNA ladder pattern of gel electrophoresis: We observed DNA ladder pattern of gel electrophoresis of extracted DNAs from dead A549 cells. Conclusion: We concluded that the mechanism of interferon-$\gamma$induced cytotoxicity on lung cancer cell line, A549 be via apoptosis.

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The Environmental and Ecological Meaning of Bibo Landscape in Otgol Village (옻골마을 비보경관의 환경생태적 의미)

  • Jang, Byoung-Kwan;Whang, Bo-Chul
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.2
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    • pp.32-41
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    • 2008
  • An empirical study and environmental and ecological analysis were conducted on Otgol Village(a village of the Gyeongju Choi's clan in Daegu) where an enclosed pond and groves are still observed. In particular, the enclosed pond and groves and village water system were investigated from an ecological perspective. The enclosed landscape is described based on feng shui principles and the environmental and ecological significance were examined. In general, the environmental and ecological significance is very broad; however, they were analyzed in terms of the quality of life as an empirical study as follows: First, water quality was measured to investigate the improvement of continuous water system functions. In other words, water quality was measured at East Valley(resting space), West Valley(living space), the enclosed pond where the two valleys merge, and the stream that flows out of the pond. Second, the climate functions of the enclosed groves that border the village were examined. In other words, temperature was measured in two places(200m distance from the center of the groves). Third, whether or not a sound ecosystem can be sustained was investigated. In other words, landscape ecological indicators were chosen and measured. The results are as follows: First, the enclosed pond played the role of purifying water quality. While the East Valley has been popular with men for its rock walls and torrents, the West Valley has been popular with women as a living space(ex: doing the laundry). Therefore, the difference of water quality can be explained. Second, since enclosed groves are in a small village forest, they are very weak in terms of being wind proof and temperature reduction effects. Instead, they play the role of the village boundary. Third, the groves are ecologically sound considering the landscape ecological indicators and are similar to ordinary traditional rural villages. In terms of the connection of the green zone, the village groves are well connected to the village boundary wood. If the village groves are restored, in particular, they would offer a decent habitat for grove creatures. According to this study, the traditional village space was formed upon the influence of Feng Shui theories that are based on environmental and ecological principles that focus on the harmony between humans and nature. From the environmental and ecological perspective, the enclosed pond and groves are important factors in building a sustainable village. The diverse water space would help to improve water quality and increase water volume by promoting the water circulation system. In addition, the village woods would surround the village and decrease the temperature and humidity difference between winter and summer. If the groves are small and badly damaged, however, they are meaningful only in dividing the region. The overall improvement of a forestation system and botanical composition may increase the biological diversity and promote the migration of species. Otgol Village has developed an enclosed landscape to improve the village environment. In other words, a sound and refreshing living environment can be developed when the natural ecological system is well understood and properly preserved. Additionally, this traditional village planning will be the environmental and ecological method. From the perspective of environmental ecology, therefore, a traditional village is recommended.

Studies on the Effect of Diffusion Process to Decay Resistance of Mine Props (간이처리법(簡易處理法)에 의한 갱목(坑木)의 내부효력(耐腐効力)에 관한 연구(硏究))

  • Shim, Chong Supp;Shin, Dong So;Jung, Hee Suk
    • Journal of Korean Society of Forest Science
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    • v.29 no.1
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    • pp.1-19
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    • 1976
  • This study has been made to make an observation regarding present status of the coal mine props which is desperately needed for coal production, despite of great shortage of the timber resources in this country, and investigate the effects of diffusion process on the decay resistances of the mine props as applied preservatives of Malenit and chromated zinc chloride. The results are as follows. 1. Present status of the coal mine props Total demand of coal mine props in the year of 1975 was approximately 456 thousand cubic meters. The main species used for mine props are conifer (mainly Pinus densiflora) and hardwood (mainly Quercus). Portions between them are half and half. With non fixed specification, wide varieties of timber in size and form are used. And volume of wood used per ton-of coal production shows also wide range from 0.017 cubic meter to 0.03 cubic meter. 2. Decay resistance test a) The oven dry weight decreased between untreated specimen and treated specimen has not shown any significantly, although it has shown some differences in average values between them. It may be caused by the shorter length of the test. b) The strength of compression test between untreated specimen and treated specimen has also shown the same results as shown in case of weight decrease. Reasons assumed are the same. c) The amounts of the extractives in one percent of sodium hydroxide (NaOH) between untreated and treated specimen have shown the large value in case of untreated specimen than that of treated. 3. The economical benifit between untreated and treated wood when applied in field has seen better in long term base in case of treated wood, although the primary cost of treated wood add a little bit more cost than that of the untreated wood.

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Effect of Supplementary Actinomycetes (Nocardia sp. CS682) Ferment on the Laying Performance, Blood Parameters, Immunoglobulin and Small Intestinal Microflora Contents in Laying Hens (방선균(Nocardia sp. CS682) 발효물의 급여가 산란계의 생산성, 혈액성상, 면역글로불린 및 소장내 미생물 함량에 미치는 영향)

  • Rhee, Ah-Reum;Shin, Dong-Hun;Kim, Chan-Ho;Jung, Byoung-Yun;Yoo, Jin-Chul;Hong, Young-Ho;Paik, In-Kee
    • Korean Journal of Poultry Science
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    • v.38 no.1
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    • pp.59-69
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    • 2011
  • This study was conducted to investigate the effects of dietary supplementation of CS682, a fermentation product of Actinomycetae(Nocardia sp. CS682), and its commercial product DSC682$^{(R)}$ on the performance, blood parameters, intestinal microflora, and immune response in laying hens. Hy-Line Brown$^{(R)}$ laying hens were housed in two bird cages. Feeding trial lasted 5 wk under 16.5 h:7.5 h(L:D) lighting regimen. In Exp.1, a total of 480 birds of 86 wk old were assigned to four dietary treatments: Control, Antibiotics (6 ppm avilamycin), CS682-0.1 (CS682 0.1%) and CS682-1.0 (CS682 1.0% supplementation). Each treatment was replicated five times with 24 birds (or 12 cages) per replication. In Exp. 2, a total of 1,000 birds of 26 wk old were assigned to five dietary treatments: Control, Antibiotics (6 ppm avilamycin), DCS682-0.05 (DCS682 0.05%), DCS682-0.1 (DCS682 0.1%), DCS682-0.2 (DCS682 0.2% supplementation). Each treatment was replicated five times with 40 birds (or 20 cages) per replication. In Exp. 1, there were no significant differences among treatments in egg production, egg weight, broken & soft egg production, feed intake, and feed conversion ratio. Also, there were no significant differences among treatments in eggshell thickness, eggshell color and Haugh unit. However, eggshell strength was significantly (p<0.05) greater in CS682 and Antibiotics treatments than Control, and egg yolk color was significantly (p<0.05) higher in CS682-1.0 than Control. In Exp. 2, feed intake was significantly (p<0.05) lower in DSC682-0.05 than Control. Lightness(L) of Hunter Lab color of eggshell of DCS and Antibiotics treatments was significantly (p<0.05) lower than Control. Egg yolk color of DCS 0.1 and 0.2 treatments was significantly (p<0.05) higher than Control. Haugh unit increased significantly (p<0.05) in Antibiotics and DCS682-0.1 treatments. The immunoglobulin levels of plasma (IgG and IgA) and eggyolk (IgY) were not significantly affected by treatments. Antibiotics and CS682 or DCS682 treatments significantly (p<0.05 or 0.01) influenced some of the erythrocytes and leukocytes parameters in blood. In Exp.1, mean corpuscular volume (MCV) decreased by CS682 treatments and mean corpuscular hemoglobin (MCH) was highest in Antibiotics treatments. In Exp.2, the level of monocyte (MO) decreased in DCS682-0.10 and 0.20 treatments. The cfu of C. perfringens and S. typhimurium in small intestinal content were highest in Control and lowest in Antibiotics in both experiments. In Exp. 2, DSC682-0.05 and -0.1 treatments were highest and Antibiotic treatment was lowest in Lactobacilli spp. The results of the present layer experiments indicated that supplementation of 0.1~0.2% CS682 or DCS682 may increase eggshell strength, color of eggshell and eggyolk, Haugh unit, and control harmful intestinal microbes.

Air Cavity Effects on the Absorbed Dose for 4-, 6- and 10-MV X-ray Beams : Larynx Model (4-, 6-, 10-MV X-선원에서 공기동이 흡수선량에 미치는 효과 : 후두모형)

  • Kim Chang-Seon;Yang Dae-Sik;Kim Chul-Yong;Choi Myung-Sun
    • Radiation Oncology Journal
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    • v.15 no.4
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    • pp.393-402
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    • 1997
  • Purpose : When an x-ray beam of small field size is irradiated to target area containing an air cavity, such as larynx, the underdosing effect is observed in the region near the interfaces of air and soft tissue. With a larynx model, air cavity embedded in tissue-equivalent material, this study is intonded for examining Parameters, such as beam quality, field size, and cavity size, to affect the dose distribution near the air cavity. Materials and Methods : Three x-rar beams, 4-, 6- and 10-MV, were employed to Perform a measurement using a 2cm $(width){\times}L$ (length in cm, one side of x-ray field used 2cm (height) air cavity in the simulated larynx. A thin window parallel-plate chamber connected to an electrometer was used for a dosimetry system. A ratio of the dose at various distances from the cavity-tissue interface to the dose at the same points in a homogeneous Phantom (ebservedlexpected ratio, O/E) normalized buildup curves, and ratio of distal surface dose to dose at the maximum buildup depth were examined for various field sizes. Measurement for cavity size effect was performed by varying the height (Z) of the air cavity with the width kept constant for several field sizes. Results : No underdosing effect for 4-MV beam for fields larger than $5cm\times5cm$ was found For both 6- and 10-MV beams, the underdosing portion of the larynx at the distal surface was seen to occur for small fields, $4cm\times4cm\;and\;5cm\times5cm$. The underdosed tissue was increased in its volume with beam energy even for similar surface doses. The relative distal surface dose to maximum dose was changed to 0.99 from 0.95, 0.92, and 0.91 for 4-, 6-, and 10-MV, respectively, with increasing field size, $4cm\times4cm\;to\;8cm\times8cm$, For 6- and 10-MV beams, the dose at the surface of the cavity is measured less than the predicted by about two and three percent. respectively. but decrease was found for 4-MV beam for $5cm\times5cm$ field. For the $4cm\timesL\timesZ$ (height in cm). varying depth from 0.0 to 4.8cm, cavity, O/E> 1.0 was observed regardless of the cavity size for any field larger than about $8cm\times8cm$. Conclusion : The magnitude of underdosing depends on beam energy, field size. and cavity size for the larynx model. Based on the result of the study. caution must be used when a small field of a high quality x-ray beam is irradiated to regions including air cavities. and especially the region where the tumor extends to the surface. Low quality beam. such as. 4-MV x-ray, and larger fields can be used preferably to reduce the risk of underdosing, local failure. In the case of high quality beams such as 6- and 10-MV x-rays, however. an additional boost field is recommended to add for the compensation of the underdosing region when a typically used treatment field. $8cm\times8cm$, is employed.

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Evaluation of Parameters of Gas Exchange During Partial Liquid Ventilation in Normal Rabbit Lung (토끼의 정상 폐 모델에서 부분액체환기 시 가스교환에 영향을 주는 인자들에 대한 연구)

  • An, Chang-Hyeok;Koh, Young-Min;Park, Chong-Wung;Suh, Gee-Young;Koh, Won-Jung;Lim, Sung-Yong;Kim, Cheol-Hong;Ahn, Young-Mee;Chung, Man-Pyo;Kim, Ho-Joong;Kwon, O-Jung
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.1
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    • pp.14-23
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    • 2002
  • Background: The opitmal ventilator setting during partial liquid ventilation(PLV) is controversial. This study investigated the effects of various gas exchange parameters during PLV in normal rabbit lungs in order to aid in the development of an optimal ventilator setting during PLV. Methods: Seven New-Zealand white rabbits were ventilated in pressure-controlled mode with the following settings; tidal volume($V_T$) 8 mL/kg, positive end-expiratory pressure(PEEP) 4 $cmH_2O$, inspiratory-to-expiratory ratio(I:E ratio) 1:2, fraction of inspired oxygen($F_TO_2$) 1.0. The respiration rate(RR) was adjusted to keep $PaCO_2$ between 35~45 mmHg. The ventilator settings were changed every 30 min in the following sequence : (1) Baseline, as the basal ventilator setting, (2) Inverse ratio, I:E ratio 2:1, (3) high PEEP, adjust PEEP to achieve the same mean inspiratory pressure (MIP) as in the inverse ratio, (4) High $V_T$, $V_T$ 15 mL/kg, (5) high RR, the same minute ventilation (MV) as in the High $V_T$. Subsequently, the same protocol was repeated after instilling 18 mL/kg of perfluorodecalin for PLV. The parameters of gas exchange, lung mechanics, and hemodynamics were examined. Results: (1) The gas ventilation(GV) group showed no significant changes in the $PaO_2$ at all phases. The $PaCO_2$ was lower and the pH was higher at the high $V_T$ and high RR phases(p<0.05). No significant changes in the lung mechanics and hemodynamics parameters were observed. (2) The baseline $PaO_2$ for the PLV was $312{\pm}$ mmHg. This was significantly lower when decreased compared to the baseline $PaO_2$ for GV which was $504{\pm}81$ mmHg(p=0.001). During PLV, the $PaO_2$, was significantly higher at the high PEEP($452{\pm}38$ mmHg) and high $V_T$ ($461{\pm}53$ mmHg) phases compared with the baseline phase. However, it did not change significantly during the inverse I:E ratio or the high RR phases. (3) The $PaCO_2$ was significantly lower at high $V_T$ and RR phases for both the GV and PLV. During the PLV, $PaCO_2$ were significantly higher compared to the GV (p<0.05). (4) There were no important or significant changes in of baseline and high RR phases lung mechanics and hemodynamics parameters during the PLV. Conclusion: During PLV in the normal lung, adequate $V_T$ and PEEP are important for optimal oxygenation.

Word-of-Mouth Effect for Online Sales of K-Beauty Products: Centered on China SINA Weibo and Meipai (K-Beauty 구전효과가 온라인 매출액에 미치는 영향: 중국 SINA Weibo와 Meipai 중심으로)

  • Liu, Meina;Lim, Gyoo Gun
    • Journal of Intelligence and Information Systems
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    • v.25 no.1
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    • pp.197-218
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    • 2019
  • In addition to economic growth and national income increase, China is also experiencing rapid growth in consumption of cosmetics. About 67% of the total trade volume of Chinese cosmetics is made by e-commerce and especially K-Beauty products, which are Korean cosmetics are very popular. According to previous studies, 80% of consumer goods such as cosmetics are affected by the word of mouth information, searching the product information before purchase. Mostly, consumers acquire information related to cosmetics through comments made by other consumers on SNS such as SINA Weibo and Wechat, and recently they also use information about beauty related video channels. Most of the previous online word-of-mouth researches were mainly focused on media itself such as Facebook, Twitter, and blogs. However, the informational characteristics and the expression forms are also diverse. Typical types are text, picture, and video. This study focused on these types. We analyze the unstructured data of SINA Weibo, the SNS representative platform of China, and Meipai, the video platform, and analyze the impact of K-Beauty brand sales by dividing online word-of-mouth information with quantity and direction information. We analyzed about 330,000 data from Meipai, and 110,000 data from SINA Weibo and analyzed the basic properties of cosmetics. As a result of analysis, the amount of online word-of-mouth information has a positive effect on the sales of cosmetics irrespective of the type of media. However, the online videos showed higher impacts than the pictures and texts. Therefore, it is more effective for companies to carry out advertising and promotional activities in parallel with the existing SNS as well as video related information. It is understood that it is important to generate the frequency of exposure irrespective of media type. The positiveness of the video media was significant but the positiveness of the picture and text media was not significant. Due to the nature of information types, the amount of information in video media is more than that in text-oriented media, and video-related channels are emerging all over the world. In particular, China has made a number of video platforms in recent years and has enjoyed popularity among teenagers and thirties. As a result, existing SNS users are being dispersed to video media. We also analyzed the effect of online type of information on the online cosmetics sales by dividing the product type of cosmetics into basic cosmetics and color cosmetics. As a result, basic cosmetics had a positive effect on the sales according to the number of online videos and it was affected by the negative information of the videos. In the case of basic cosmetics, effects or characteristics do not appear immediately like color cosmetics, so information such as changes after use is often transmitted over a period of time. Therefore, it is important for companies to move more quickly to issues generated from video media. Color cosmetics are largely influenced by negative oral statements and sensitive to picture and text-oriented media. Information such as picture and text has the advantage and disadvantage that the process of making it can be made easier than video. Therefore, complaints and opinions are generally expressed in SNS quickly and immediately. Finally, we analyzed how product diversity affects sales according to online word of mouth information type. As a result of the analysis, it can be confirmed that when a variety of products are introduced in a video channel, they have a positive effect on online cosmetics sales. The significance of this study in the theoretical aspect is that, as in the previous studies, online sales have basically proved that K-Beauty cosmetics are also influenced by word-of-mouth. However this study focused on media types and both media have a positive impact on sales, as in previous studies, but it has been proven that video is more informative and influencing than text, depending on media abundance. In addition, according to the existing research on information direction, it is said that the negative influence has more influence, but in the basic study, the correlation is not significant, but the effect of negation in the case of color cosmetics is large. In the case of temporal fashion products such as color cosmetics, fast oral effect is influenced. In practical terms, it is expected that it will be helpful to use advertising strategies on the sales and advertising strategy of K-Beauty cosmetics in China by distinguishing basic and color cosmetics. In addition, it can be said that it recognized the importance of a video advertising strategy such as YouTube and one-person media. The results of this study can be used as basic data for analyzing the big data in understanding the Chinese cosmetics market and establishing appropriate strategies and marketing utilization of related companies.