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Effect of Band Spot Fertilization for Reduction of Additional Application in Plastic Film Mulching Cultivation of Onion(Allium cepa L.) (양파 비닐피복 재배에서 추비 절감을 위한 토중시비 효과)

  • Yang, Chang-Hyu;Ryu, Chul-Hyun;Shin, Bok-Woo;Kang, Seung-Won
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.2
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    • pp.102-108
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    • 2006
  • It is very important to improve fertilizer use efficiency for the saving of fertilizers and for environmental purposes as well. However, there was no effective ways for the fertilization in the mid of growth under the plastic film mulching cultivation so far. For this, a Band Spotty Fertilization (BSF) machine was developed recently. So, we tried to establish a low input fertilization technique using this BSF machine in the vinyl mulching cultivation of onion (Allium cepa L.). Fertilization efficiency, soil properties, and crop yield were examined and compared among treatments from 2000 to 2001. The content of exchangeable K in soils were higher after fertilization but that of available $P_2O_5$ was lower than before the experiment in all plots. The content of nitrate-N was highest at the early growth stage, and higher in BSF plots than that of conventional fertilization (CF). BSF plot showed higher growth rate, and uptake amount of nitrogen of onion by 59-69% than that of CF. N use efficiency in BSF was higher in the order of two time-split application, one time-split application, and three time application. K use efficiency was high 13-17% BSF plots than that in CF($63kg\;ha^{-1}$) plots. The amount of residual N in soils was high by 8-14% in BSF plots compared to that in CF plots, and the loss of N was lowered 26-34% by BSF. Also, the amount of residual K in soils was high by 13-18% and the loss of K was low by 29-31% in BSF plots compared to that in CF plots. The yield of onions increased by 7-13% by BSF due to increased diameter and weight of bulbs. As the results, N fertilization efficiency increased by 22-42% by BSF.

Effect of Aprotinin on Changes in Plasma Thromboxane $B_2$ and Endothelin-1 Concentratin after Extracorporeal Circulation (체외순환후 혈중 Thromboxane $B_2$와 Endothelin-1 농도 변화에 미치는 Aprotinin의 효과)

  • Lim, Cheong;Yun, Tae-jin;Kim, Yeon-seung;Kim, Seung-hoo;Lee, Jae-dam;Rho, Joon-Ryang;Song, Meong-Gun
    • Journal of Chest Surgery
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    • v.33 no.3
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    • pp.221-229
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    • 2000
  • Background: Thromboxane A2 and endothelin-1 are the potent vasoconstrictors affecting pulmonary pathophysiology in response to whole body inflammatin following CPB. Aprotinin, as an antiiflammatory agent, may decrease the release of such vasoactive substance from pulmonary tissues, preventing pulmonary hypertension after cardiopulmonary bypass. Material and Method: Ten mongrel dogs(Bwt. ac. 20kg) were subjected to cardioupulmonary bypass for 2 hours and postbypass pulmonary vascular resistance(0, 1, 2, 3 hours) were compared with prebypass level. The dogs were divided into 2 groups; control group(n-5) and aprotinin group(n=5). In the aprotinin group, aprotinin was administered as follows; 50,000 KIU/kg mixed in pump priming solution, 50,000 KIU/kg prebypass intravenous infusion over 30 minutes, 10,000 KIU/kg/hour postbypass continuous infusion. Prebypass and postbypass 0, 1, 2, 3 hour pulmonary vascular resistance were measured. At prebypass and postbypass 0, 90, 180 minutes, blood samples were obtained from pulmonary arterial and left atrial catherers for the assay of plasma thromboxane B2 a stable metabolite of thromboxane A2, and endothelin-1 concentrations. Result: The ratios of pustbypass over prebypass pulmonary vascular at postbypass 0, 1, 2, 3 hours were 1.28$\pm$0.20, 1.82$\pm$0.23, 1.90$\pm$0.19, 2.14$\pm$0.18 in control group, 1.58$\pm$0.18, 1.73$\pm$0.01, 1.66$\pm$0.10, 1.50$\pm$0.08 in aprotinin group ; the ratios gradually increased in control group while decreased or fluctuated after postbypass 1 hour in aprotinin group. There was statistically significant difference between control group and aprotinin group at postbypass 3 hours(P=0.014). Pulmonary arterial plasma concentration of thromboxane B2(pg/ml) at prebypass, postbypass 0, 90, 180 minutes were 346.4$\pm$61.9, 529.3$\pm$197.6, 578.3$\pm$255.8, 493.3$\pm$171.3 in control group, 323.8$\pm$118.0, 422.6$\pm$75.6, 412.3$\pm$59.9, 394.5$\pm$154.0 in aprotinin group. Left atrial concentrations were 339.3$\pm$89.2, 667.0$\pm$65.7, 731.2$\pm$192.7, 607.5$\pm$165.9 in control group, 330.0$\pm$111.2, 468.4$\pm$190.3, 425.4$\pm$193.6, 4.7.3$\pm$142.8 in aprotinin group. These results showed decrement of pulmonary thromboxane A2 generation in aprotinin group. Pulmonary arterial concentrations of endothelin-1(fmol/ml) at the same time sequence were 7.84$\pm$0.31, 13.2$\pm$0.51, 15.0$\pm$1.22, 16.3$\pm$1.73 in control group, 7.76$\pm$0.12, 15.3$\pm$0.71, 22.6$\pm$6.62, 14.9$\pm$1.11 in aprotinin group. Left atrial concentrations were 7.61$\pm$17.2, 57.1$\pm$28.4, 18.9$\pm$18.2, 31.5$\pm$20.5 in control group, 5.61$\pm$7.61, 37.0$\pm$26.2, 28.6$\pm$21.7, 37.8$\pm$30.6 in aprotinin group. These results showed that aprotinin had no effect on plasma endothelin-1 concentration after cardiopulmonary bypass. Conclusion: Administration of aprotinin during cardiopulmonary bypass could attenuate the increase in pulmonary vascular resistance after bypass. Inhibition of pulmonary thromboxane A2 generation was thought to be one of the mechanism of this effect. Aprotinin had no effect on postbypass endothelin-1 concentration.

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Snuffbox Arteriovenous Fistula Formation for Hemodialysis (Snuffbox에 시행한 혈액투석을 위한 동정맥루조성술)

  • 서필원;류재욱;박정옥;장성욱;김미순;박성식;김삼현
    • Journal of Chest Surgery
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    • v.37 no.2
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    • pp.154-159
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    • 2004
  • The arteriovenous fistula (AVF), which maintains satisfactory blood flow, is necessary to the patients of end-stage renal disease for the long term hemodialysis. We performed the snuffbox fistula as the first operation for hemodialysis vascular access. This study was performed to investigate the patency rates, complications, risk factors for occlusion of the AVF, and the types of reoperations. Material and Method: We performed 146 snuffbox fistulas from Jun. 1994 to Dec. 2001 The records of the patients except six patients who were lost from follow up were analyzed retrospectively, Mean age and male:female ratio were 52$\pm$15 years (range, 17∼79 years) and 80 : 60 respectively. Diabetes mellitus and hypertension were combined in 47 patients and 101 respectively. Preoperative levels of creatinine and potassium were 9.09$\pm$3.68 mg/dL (range, 2.55∼20.09 mg/dL) and 4.7$\pm$0.9 mmol/L (range, 2.3∼8.1 mmol/L). One hundred thirteen cases of the snuffbox fistulas were done at left side hand and the others at right hand. Result: Mean follow up period of the patients was 41.8$\pm$31.0 months (range, 0.2∼108,8 months). During the follow up period, 35 occlusions of AVF occurred and these AVFs were patent for 9.8$\pm$10.1 months (range, 0.1∼40.4 months). The patency rates of f month, and 1, 2, 3, 5 years were known as 92.8, 80.2, 73.8, 71.3, 69.6% respectively. Right sided snuffbox fistulas (p-value=0.045) and old age (p-value=0.048) were revealed as significant risk factors for occlusion of AVF. The postoperative complications consisted of occlusions of AVF caused by intimal hyperplasia of vein in 24, thrombosis in nine, stenosis of anastomosis site in three, and venous hypertensions in two. After the first operation 37 patients underwent 86 reoperations. Conclusion: The snuffbox fistulas showed acceptable patency rates and low complication rates. The snuffbox fistulas as the first operation for AVF formation can be a good option for the patients with end-stage renal disease.

Attitude and Participation Status on District Health Planning in Officials of Health Centers (보건소 공무원의 지역보건의료계획 수립 참여실태 및 태도)

  • Jeong, Han-Ho;Kam, Sin;Han, Chang-Hyun
    • Journal of agricultural medicine and community health
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    • v.28 no.2
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    • pp.135-154
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    • 2003
  • Objectives: This study was performed to investigate attitude and participation status on district health planning of officials in Health Centers. Methods: The data collected by self-administered questionnaire survey of 674 officials of Health Centers and the data on district health planning of 28 Health Centers in Gyeongsangbuk-do and Daegu metropolitan city were analyzed. Results: Only 13.6% of officials of Health Centers responded that they had read 'the second district health planning paper' thoroughly and 12.5% of officials of Health Centers replied that they had known contents of 'the second district health planning paper' fully. 56.9% of officials of Health Centers didn't have 'the second district health planning paper'. Thirty five point four percent(35.4%) of health center officials replied that the mayor's or county executive's concern about the district health planning was high, 22.4% in councilors, 77.8% in Health Center chiefs, 44.9% in Health Center officials, 43.9% in him or her. Among respondents, 58.6% of Health Center officials replied that district health planning was necessary and 38.0% of subjects replied that the degree of utilization of district health planning was high. About thirty seven percent(36.9%) of respondents participated in making out 'the second district health planning paper' and 49.6% in 'the third district health planning paper'. Health Center officials replied that the most serious problem of district health planning was 'lack of budget and personnels'(39.8%), 'lack of concern for district health planning'(21.4%) and the most important thing to improve district health planning was 'establishing department for health planning', 'adjustment of establishment time for district health planning'. Conclusions: In order to establish effective district health planning, it would be necessary to secure budget and personnels, to promote the county executive's concern and Health Center officials' concern about the district health planning, to establish department for health planning, and to adjust establishment time for district health planning.

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Social Contribution and Future Direction of Home Economics Education (가정교육학의 사회적 기여와 미래 방향)

  • Chae, Jung-Hyun;Lee, Soo-Hee;Yoo, Tae-Myung
    • Journal of Korean Home Economics Education Association
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    • v.22 no.4
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    • pp.139-154
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    • 2010
  • The purpose of this study was to put forth of a future vision from examining of social contribution, future direction, and theoretical framework of home economics education and its cases of practice in educational setting. This study was carried with literature review, and results of study were as follows: First, home economics education should contribute to society through (1) educating individuals suffering from family tiredness to maintain autonomous lives free from distorted family ideology by being critically conscious of them in individual dimension, (2) educating individuals to develop a competence as a citizen to be critical of family ego-centric ideas and to participate and support communal life in family-social dimension, and (3) educating female and male students gender sensitivity and management of family life to be critical of gender discrimination ideology in gender dimension. Second, future home economics education should reinforce all round character education which let students develop their creativity and problem solving ability and foster students' wisdom of life with honesty and morality rather than merely acquiring knowledge in individual dimension. Third, this study employed Brown and Paolucci's conceptual scheme as a theoretical framework which focuses on the role of home economics education leading individuals and families as a changing agent. This framework let individuals and families to critically examine the social character and ideas provided by existing social, economical, and political systems, and to transform social character and ideas to build an ideal societal condition when there are any problems in them. Fourth, this study examined sample classroom instruction of Japan and FCCLA of United States of America to see how they educate students to become a changing agent. In conclusion, future vision of home economics education is to accomplish family revolution to sustain happy family relation and their family lives in which they feel pampered from achievement and free from distorted family ideology. For home economics to accomplish family revolution, it should strengthen education for empowerment, enlightenment, and autonomy. This study calls for immediate paradigm shift not as an occupational but as a practical-critical praxis subject matter for family revolution through home economics education.

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A Study on Ancestral Service Preparation and Sacrificial Consciousness of Housekeepers Living in Pusan and Yeosu Area (부산지역과 전남 여수지역 주부들의 제례준비 및 제례의식 조사 연구)

  • 정복미;정해옥;김은실
    • Culinary science and hospitality research
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    • v.10 no.3
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    • pp.135-154
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    • 2004
  • This study surveyed ancestral service preparation and sacrificial consciousness of housewives living in Pusan and Yeosu area. Statistical analysis of chi-square test was carried out by using SAS program. The results are summarized as follows. l. In major general characteristics of subjects, the forties(35.56%), Buddhism (57.79%), high school education(52.54%), a couple with children(63.45%) were the most abundant. 2. The time of sacrificial rites in both areas was usually hold from 23:00 to 01:00 (47.16%). The housewives having a job hold earlier the service than the full-time housewives(p<0.05). 3. The range of ancestor-memorial rites was usually up to 3rd generation(34.47%). The leader of sacrificial ceremony was mainly the eldest grandson by the eldest son (78.28%) in the old subjects and a person of wealth in the young subjects(p<0.05). 4. There were more positive answers for the necessity of a sacrificial ceremony (57.32%). Older than 50 years of subjects thought the sacrificial rites should be held(70.77%), while as the age of subjects was younger, they realized less necessity for that(p<0.05). Sacrificial consciousness was higher in Buddhists than the other religionists(p<0.0001). The sacrificial rites was thought to be needed for their harmonious family(50.43%). Younger subjects thought that it is necessary to succeed that as the tradition, while older housewives thought that it would contribute toward peace in their family(p<0.05). Buddhists and Christians answered that it was good for harmonious family, and Catholics and the others for tradition(p<0.01). Their consideration of sacrificial rites in the future was higher in keeping the traditional practice (37.04%) and Buddhists took higher these consideration(43.17%). Considering the sacrificial consciousness, there were statistical differences among the religionists (p<0.0001). The eldest daughter-in-raw had a different opinion about the following up the method of sacrificial ceremony from second eldest daughter-in-raw and the next one(p<0.05). The housewives in Pusan were showing more the affirmative attitudes to keep the traditional practice than those in Yeosu.

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The Prediction of DEA based Efficiency Rating for Venture Business Using Multi-class SVM (다분류 SVM을 이용한 DEA기반 벤처기업 효율성등급 예측모형)

  • Park, Ji-Young;Hong, Tae-Ho
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.139-155
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    • 2009
  • For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

Investigating the Influence of Perceived Usefulness and Self-Efficacy on Online WOM Adoption Based on Cognitive Dissonance Theory: Stick to Your Own Preference VS. Follow What Others Said (온라인 구전정보 수용자의 지각된 정보유용성과 자기효능감이 구전정보 수용의도에 미치는 영향에 관한 연구: 의견고수와 구전수용의 비교)

  • Lee, Jung Hyun;Park, Joo Seok;Kim, Hyun Mo;Park, Jae Hong
    • Asia pacific journal of information systems
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    • v.23 no.3
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    • pp.131-154
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    • 2013
  • New internet technologies have created a revolutionary new platform which allows consumers to make decision about product price and quality quickly and provides information about themselves through the transcript of online reviews. By expressing their feelings toward products or services on virtual opinion platforms, users extend their influence into cyberspace as electronic word-of-mouth (e-WOM). Existing research indicates that an impact of eWOM on the consumer decision process is influential. For both academic researchers and practitioners, investigating this phenomenon of information sharing in online website is essential given the increasing number of consumers using them as sources of purchase decisions. It is worthwhile to examine the extent to which opinion seekers are willing to accept and adopt online reviews and which factors encourage adoption. Discerning the most motivating aspects of information adoption in particular, could help electronic marketers better promote their brand and presence on the internet. The objectives of this study are to investigate how online WOM influences a persons' purchase decision by discovering which factors encourage information adoption. Especially focused on the self-efficacy, this research investigates how self-efficacy affects on information usefulness and adoption of online information. Although people are exposed to same review or comment about product or service, some accept the reviews while others do not. We notice that accepting online reviews mainly depends on the person's preference or personal characteristics. This study empirically examines this issue by using cognitive dissonance theory. Specifically, in the movie industry, we address few questions-is always positive WOM generating positive effect? What if the movie isn't the person's favorite genre? What if the person who is very self-assertive so doesn't take other's opinion easily? In these cases of cognitive dissonance, is always WOM generating same result? While many studies have focused on one direct of WOM which indicates positive (or negative) informative reviews or comments generate positive (or negative) results and more (or less) profits, this study investigates not only directional properties of WOM but also how people change their opinion towards product or service positive to negative, negative to positive through the online WOM. An experiment was conducted quantitatively by using a sample of 168 users who have experience within the online movie review site, 'Naver Movie'. Users were required to complete a survey regarding reviews and comments taken from the real movie page. The data reflected user's perceptions of online WOM information that determined users' adoption level. Analysis results provide empirical support for the proposed theoretical perspective. When user can't agree with the opinion of online WOM information, in other words, when cognitive dissonance between online WOM information and users' preference occurs, perceived self-efficacy significantly decreases customers' perception of usefulness. And this perception of usefulness plays an important role in determining users' intention to adopt online WOM information. Most of researches have been concentrated on characteristics of online WOM itself such as quality or vividness of information, credibility of source and direction of online WOM, etc. for describing effect of online WOM, but our results suggest that users' personal character (e.g., self-efficacy) plays decisive role for acceptance of online WOM information. Higher self-efficacy means lower possibility to accept the information that represents counter opinion because of cognitive dissonance, whereas the people that have lower self-efficacy are willing to accept the online WOM information as true and refer to purchase decision. This study suggests a model for understanding role of direction of online WOM information. Also, our result implicates the importance of online review supervision and personalized information service by confirming switching opinion negative to positive is more difficult than positive to negative through the online WOM information. This implication would help marketers to manage online reviews of their products or services.

Study on new casing materials of Agaricus bisporus (양송이의 새로운 복토재료에 관한 연구)

  • Kim, Yong-Gyun;Lee, Byung-Joo;Lee, Sun-Gye;Lee, Byung-Eui
    • Journal of Mushroom
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    • v.16 no.3
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    • pp.147-154
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    • 2018
  • This study was aimed to improve the productivity and income of mushroom farming by developing a new casing material as a substitute for clay loam casing soil, which is becoming more difficult to acquire. When the new casing materials were used for the stable production of button mushroom (Agaricus bisporus), a 1:1 mixture of clay loam and button mushroom media obtained after harvest supported 13% greater mycelial growth ($32.0kg/3.3m^2$). This material was better than clay loam soil in preventing contamination with environmental compounds and pests. The use of an inexpensive 1:1 mixture of peat moss and coco peat resulted superior mycelial growth with 4% better yield ($32.9kg/3.3m^2$) compared with conventional clay loam soil. Advantages of these casing materials included ready availability and improved productivity. Mixtures of peat moss + coco peat + zeolite (50%:30%:20%) and coco peat + coal ash (75%:25%) could substitute for conventional casing soil. Additionally, the novel mixtures containing material obtained after cultivation might be used to produce organic fertilizer.

A Pressure Adjustment Protocol for Programmable Valves

  • Kim, Kyoung-Hun;Yeo, In-Seoung;Yi, Jin-Seok;Lee, Hyung-Jin;Yang, Ji-Ho;Lee, Il-Woo
    • Journal of Korean Neurosurgical Society
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    • v.46 no.4
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    • pp.370-377
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    • 2009
  • Objective : There is no definite adjustment protocol for patients shunted with programmable valves. Therefore, we attempted to find an appropriate method to adjust the valve, initial valve-opening pressure, adjustment scale, adjustment time interval, and final valve-opening pressure of a programmable valve. Methods : Seventy patients with hydrocephalus of various etiologies were shunted with programmable shunting devices (Micro Valve with $RICKHAM^{(R)}$ Reservoir). The most common initial diseases were subarachnoid hemorrhage (SAH) and head trauma. Sixty-six patients had a communicating type of hydrocephalus, and 4 had an obstructive type of hydrocephalus. Fifty-one patients had normal pressure-type hydrocephalus and 19 patients had high pressure-type hydrocephalus. We set the initial valve pressure to $10-30\;mmH_2O$, which is lower than the preoperative lumbar tapping pressure or the intraoperative ventricular tapping pressure, conducted brain computerized tomographic (CT) scans every 2 to 3 weeks, correlated results with clinical symptoms, and reset valve-opening pressures. Results : Initial valve-opening pressures varied from 30 to $180\;mmH_2O$ (mean, $102{\pm}27.5\;mmH_2O$). In high pressure-type hydrocephalus patients, we have set the initial valve-opening pressure from 100 to $180\;mmH_2O$. We decreased the valve-opening pressure $20-30\;mmH_2O$ at every 2- or 3-week interval, until hydrocephalus-related symptoms improved and the size of the ventricle was normalized. There were 154 adjustments in 81 operations (mean, 1.9 times). In 19 high pressure-type patients, final valve-opening pressures were $30-160\;mmH_2O$, and 16 (84%) patients' symptoms had nearly improved completely. However, in 51 normal pressure-type patients, only 31 (61%) had improved. Surprisingly, in 22 of the 31 normal pressure-type improved patients, final valve-opening pressures were $30\;mmH_2O$ (16 patients) and $40\;mmH_2O$ (6 patients). Furthermore, when final valve-opening pressures were adjusted to $30\;mmH_2O$, 14 patients symptom was improved just at the point. There were 18 (22%) major complications : 7 subdural hygroma, 6 shunt obstructions, and 5 shunt infections. Conclusion : In normal pressure-type hydrocephalus, most patients improved when the final valve-opening pressure was $30\;mmH_2O$. We suggest that all normal pressure-type hydrocephalus patients be shunted with programmable valves, and their initial valve-opening pressures set to $10-30\;mmH_2O$ below their preoperative cerebrospinal fluid (CSF) pressures. If final valve-opening pressures are lowered in 20 or $30\;mmH_2O$ scale at 2- or 3-week intervals, reaching a final pressure of $30\;mmH_2O$, we believe that there is a low risk of overdrainage syndromes.