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The Significance of Plasma Urokinase-type Plasminogen Activator and Type 1 Plasminogen Activator Inhibitor in Lung Cancer (폐암에서 혈장 Urokinase-Type Plasminogen Activator 및 Type 1 Plasminogen Activator Inhibitor의 의의)

  • Park, Kwang-Joo;Kim, Hyung-Jung;Ahn, Chul-Min;Lee, Doo-Yun;Chang, Joon;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.516-524
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    • 1997
  • Background : Cancer invasion and metastasis require the dissolution of the extracellular matrix in which several proteolytic enzymes are involved. One of these enzymes is the urokinase-type plasminogen activator(u-PA), and plasminogen activator inhibitors(PAI-1, PAI-2) also have a possible role in cancer invasion and metastasis by protection of cancer itself from proteolysis by u-PA. It has been reported that the levels of u-PA and plasminogen activator inhibitors in various cancer tissues are significantly higher than those in normal tissues and have significant correlations with tumor size and lymph node involvement. Here, we measured the concentration of plasma u-PA and PAI-1 antigens in the patients with lung cancer and compared the concentration of them with histologic types and staging parameters. Methods : We measured the concentration of plasma u-PA and PAI-1 antigens using commercial ELISA kit in 37 lung cancer patients, 21 benign lung disease patients and 24 age-matched healthy controls, and we compared the concentration of them with histologic types and staging parameters in lung cancer patients. Results : The concentration of u-PA was $1.0{\pm}0.3ng/mL$ in controls, $1.0{\pm}0.3ng/mL$ in benign lung disease patients and $0.9{\pm}0.3ng/mL$ in lung cancer patients. The concentration of PAI-1 was $14.2{\pm}6.7ng/mL$ in controls, $14.9{\pm}6.3ng/mL$ in benign lung disease patients, and $22.1{\pm}9.8ng/mL$ in lung cancer patients. The concentration of PAI-1 in lung cancer patients was higher than those of benign lung disease patients and controls. The concentration of u-PA was $0.7{\pm}0.4ng/mL$ in squamous cell carcinoma, $0.8{\pm}0.3ng/mL$ in adenocarcinoma, 0.9ng/mL in large cell carcinoma, and $1.1{\pm}0.7ng/mL$ in small cell carcinoma. The concentration of PAI-1 was $22.3{\pm}7.2ng/mL$ in squamous cell carcinoma, $22.6{\pm}9.9ng/mL$ in adenocarcinoma, 42 ng/mL in large cell carcinoma, and $16.0{\pm}14.2ng/mL$ in small cell carcinoma. The concentration of u-PA was 0.74ng/mL in stage I, $1.2{\pm}0.6ng/mL$ in stage II, $0.7{\pm}0.4ng/mL$ in stage IIIA, $0.7{\pm}0.4ng/mL$ in stage IIIB, and $0.7{\pm}0.3ng/mL$ in stage IV. The concentration of PAI-1 was 21.8ng/mL in stage I, $22.7{\pm}8.7ng/mL$ in stage II, $18.4{\pm}4.9ng/mL$ in stage IIIA, $25.3{\pm}9.0ng/mL$ in stage IIIB, and $21.5{\pm}10.8ng/mL$ in stage IV. When we divided T stage into T1-3 and T4, the concentration of u-PA was $0.8{\pm}0.4ng/mL$ in T1-3 and $0.7{\pm}0.4ng/mL$ in T4, and the concentration of PAI-1 was $17.9{\pm}5.6ng/mL$ in T1-3 and $26.1{\pm}9.1ng/mL$ in T4. The concentration of PAI-1 in T4 was significantly higher than that in T1-3. The concentration of u-PA was $0.8{\pm}0.4ng/mL$ in M0 and $0.7{\pm}0.3ng/mL$ in M1, and the concentration of PAI-1 was $23.6{\pm}8.3ng/mL$ in M0 and $21.5{\pm}10.8ng/mL$ in M1. Conclusions : The plasma levels of PAI-1 in lung cancer were higher than benign lung disease and controls, and the plasma levels of PAI-1 in T4 were significantly higher than T1-3. These findings suggest involvement of PAI-1 with local invasion of lung cancer, but it should be confirmed by the data on comparison with pathological staging and tissue level in lung cancer.

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A Study on Jurisdiction under the International Aviation Terrorism Conventions (국제항공테러협약의 관할권 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.1
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    • pp.59-89
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    • 2009
  • The objectives of the 1963 Tokyo Convention cover a variety of subjects, with the intention of providing safety in aircraft, protection of life and property on board, and promoting the security of civil aviation. These objectives will be treated as follows: first, the unification of rules on jurisdiction; second, the question of filling the gap in jurisdiction; third, the scheme of maintaining law and order on board aircraft; fourth, the protection of persons acting in accordance with the Convention; fifth, the protection of the interests of disembarked persons; sixth, the question of hijacking of aircraft; and finally some general remarks on the objectives of the Convention. The Tokyo Convention mainly deals with general crimes such as murder, violence, robbery on board aircraft rather than aviation terrorism. The Article 11 of the Convention deals with hijacking in a simple way. As far as aviation terrorism is concerned 1970 Hague Convention and 1971 Montreal Convention cover the hijacking and sabotage respectively. The Problem of national jurisdiction over the offence and the offender was as tangled at the Hague and Montreal Convention, as under the Tokyo Convention. Under the Tokyo Convention the prime base of jurisdiction is the law of the flag (Article 3), but concurrent jurisdiction is also allowed on grounds of: territorial principle, active nationality and passive personality principle, security of the state, breach of flight rules, and exercise of jurisdiction necessary for the performance of obligations under multilateral agreements (Article 4). No Criminal jurisdiction exercised in accordance with national law is excluded [Article 3(2)]. However, Article 4 of the Hague Convention(hereafter Hague Article 4) and Article 5 of the Montreal Convention(hereafter Montreal Article 5), dealing with jurisdiction have moved a step further, inasmuch as the opening part of both paragraphs 1 and 2 of the Hague Article 4 and the Montreal Article 5 impose an obligation on all contracting states to take measures to establish jurisdiction over the offence (i.e., to ensure that their law is such that their courts will have jurisdiction to try offender in all the circumstances covered by Hague Article 4 and Montreal Article 5). The state of registration and the state where the aircraft lands with the hijacker still on board will have the most interest, and would be in the best position to prosecute him; the paragraphs 1(a) and (b) of the Hague Article 4 and paragraphs 1(b) and (c) of the Montreal Article 5 deal with it, respectively. However, paragraph 1(b) of the Hague Article 4 and paragraph 1(c) of the Montreal Article 5 do not specify if the aircraft is still under the control of the hijacker or if the hijacker has been overpowered by the aircraft commander, or if the offence has at all occurred in the airspace of the state of landing. The language of the paragraph would probably cover all these cases. The weaknesses of Hague Article 4 and Montreal Article 5 are however, patent. The Jurisdictions of the state of registration, the state of landing, the state of the lessee and the state where the offender is present, are concurrent. No priorities have been fixed despite a proposal to this effect in the Legal Committee and the Diplomatic Conference, and despite the fact that it was pointed out that the difficulty in accepting the Tokyo Convention has been the question of multiple jurisdiction, for the reason that it would be too difficult to determine the priorities. Disputes over the exercise of jurisdiction can be endemic, more so when Article 8(4) of the Hague Convention and the Montreal Convention give every state mentioned in Hague Article 4(1) and Montreal Article 5(1) the right to seek extradition of the offender. A solution to the problem should not have been given up only because it was difficult. Hague Article 4(3) and Montreal Article 5(3) provide that they do not exclude any criminal jurisdiction exercised in accordance with national law. Thus the provisions of the two Conventions create additional obligations on the state, and do not exclude those already existing under national laws. Although the two Conventions do not require a state to establish jurisdiction over, for example, hijacking or sabotage committed by its own nationals in a foreign aircraft anywhere in the world, they do not preclude any contracting state from doing so. However, it has be noted that any jurisdiction established merely under the national law would not make the offence an extraditable one under Article 8 of the Hague and Montreal Convention. As far as international aviation terrorism is concerned 1988 Montreal Protocol and 1991 Convention on Marking of Plastic Explosives for the Purpose of Detention are added. The former deals with airport terrorism and the latter plastic explosives. Compared to the other International Terrorism Conventions, the International Aviation Terrorism Conventions do not have clauses of the passive personality principle. If the International Aviation Terrorism Conventions need to be revised in the future, those clauses containing the passive personality principle have to be inserted for the suppression of the international aviation terrorism more effectively. Article 3 of the 1973 Convention on the Prevention and Punishment of Crimes Against Internationally Protected Persons, Including Diplomatic Agents, Article 5 of the 1979 International Convention against the Taking of Hostages and Article 6 of the 1988 Convention for the Suppression of Unlawful Acts Against the Safety of Maritime Navigation would be models that the revised International Aviation Terrorism Conventions could follow in the future.

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Comparison of Effects of Normothermic and Hypothermic Cardiopulmonary Bypass on Cerebral Metabolism During Cardiac Surgery (체외순환 시 뇌 대사에 대한 정상 체온 체외순환과 저 체온 체외순환의 임상적 영향에 관한 비교연구)

  • 조광현;박경택;김경현;최석철;최국렬;황윤호
    • Journal of Chest Surgery
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    • v.35 no.6
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    • pp.420-429
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    • 2002
  • Moderate hypothermic cardiopulmonary bypass (CPB) has commonly been used in cardiac surgery. Several cardiac centers recently practice normothermic CPB in cardiac surgery, However, the clinical effect and safety of normothermic CPB on cerebral metabolism are not established and not fully understood. This study was prospectively designed to evaluate the clinical influence of normothermic CPB on brain metabolism and to compare it with that of moderate hypothermic CPB. Material and Method: Thirty-six adult patients scheduled for elective cardiac surgery were randomized to receive normothermic (nasopharyngeal temperature >34.5 $^{\circ}C$, n=18) or hypothermic (nasopharyngeal temperature 29~3$0^{\circ}C$, n=18) CPB with nonpulsatile pump. Middle cerebral artery blood flow velocity (VMCA), cerebral arteriovenous oxygen content difference (CAVO$_{2}$), cerebral oxygen extraction (COE), modified cerebral metabolic rate for oxygen (MCMRO$_{2}$), cerebral oxygen transport (TEO$_{2}$), cerebral venous desaturation (oxygen saturation in internal jugular bulb blood$\leq$50 %), and arterial and internal jugular bulb blood gas analysis were measured during six phases of the operation: Pre-CPB (control), CPB-10 min, Rewarm-1 (nasopharyngeal temperature 34 $^{\circ}C$ in the hypothermic group), Rewarm-2 (nasopharyngeal temperature 37 $^{\circ}C$ in the both groups), CPB-off and Post-CPB (skin closure after CPB-off). Postoperaitve neuropsychologic complications were observed in all patients. All variables were compared between the two groups. Result: VMCA at Rewarm-2 was higher in the hypothermic group (153.11$\pm$8.98%) than in the normothermic group (131.18$\pm$6.94%) (p<0.05). CAVO$_{2}$ (3.47$\pm$0.21 vs 4.28$\pm$0.29 mL/dL, p<0.05), COE (0.30$\pm$0.02 vs 0.39$\pm$0.02, p<0.05) and MCMRO$_{2}$ (4.71 $\pm$0.42 vs 5.36$\pm$0.45, p<0.05) at CPB-10 min were lower in the hypothermic group than in the normothermic group. The hypothermic group had higher TEO$_{2}$ than the normothermic group at CPB-10 (1,527.60$\pm$25.84 vs 1,368.74$\pm$20.03, p<0.05), Rewarm-2 (1,757.50$\pm$32.30 vs 1,478.60$\pm$27.41, p<0.05) and Post-CPB (1,734.37$\pm$41.45 vs 1,597.68$\pm$27.50, p<0.05). Internal jugular bulb oxygen tension (40.96$\pm$1.16 vs 34.79$\pm$2.18 mmHg, p<0.05), saturation (72.63$\pm$2.68 vs 64.76$\pm$2.49 %, p<0.05) and content (8.08$\pm$0.34 vs 6.78$\pm$0.43 mL/dL, p<0.05) at CPB-10 were higher in the hypothermic group than in the normothermic group. The hypothermic group had less incidence of postoperative neurologic complication (delirium) than the normothermic group (2 vs 4 patients, p<0.05). Lasting periods of postoperative delirium were shorter in the hypothermic group than in the normothermic group (60 vs 160 hrs, p<0.01). Conclusion: These results indicate that normothermic CPB should not be routinely applied in all cardiac surgery, especially advanced age or the clinical situations that require prolonged operative time. Moderate hypothermic CPB may have beneficial influences relatively on brain metabolism and postoperative neuropsychologic outcomes when compared with normothermic CPB.

Radioimmunoassay Reagent Survey and Evaluation (검사별 radioimmunoassay시약 조사 및 비교실험)

  • Kim, Ji-Na;An, Jae-seok;Jeon, Young-woo;Yoon, Sang-hyuk;Kim, Yoon-cheol
    • The Korean Journal of Nuclear Medicine Technology
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    • v.25 no.1
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    • pp.34-40
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    • 2021
  • Purpose If a new test is introduced or reagents are changed in the laboratory of a medical institution, the characteristics of the test should be analyzed according to the procedure and the assessment of reagents should be made. However, several necessary conditions must be met to perform all required comparative evaluations, first enough samples should be prepared for each test, and secondly, various reagents applicable to the comparative evaluations must be supplied. Even if enough comparative evaluations have been done, there is a limit to the fact that the data variation for the new reagent represents the overall patient data variation, The fact puts a burden on the laboratory to the change the reagent. Due to these various difficulties, reagent changes in the laboratory are limited. In order to introduce a competitive bid, the institute conducted a full investigation of Radioimmunoassay(RIA) reagents for each test and established the range of reagents available in the laboratory through comparative evaluations. We wanted to share this process. Materials and Methods There are 20 items of tests conducted in our laboratory except for consignment tests. For each test, RIA reagents that can be used were fully investigated with the reference to external quality control report. and the manuals for each reagent were obtained. Each reagent was checked for the manual to check the test method, Incubation time, sample volume needed for the test. After that, the primary selection was made according to whether it was available in this laboratory. The primary selected reagents were supplied with 2kits based on 100tests, and the data correlation test, sensitivity measurement, recovery rate measurement, and dilution test were conducted. The secondary selection was performed according to the results of the comparative evaluation. The reagents that passed the primary and secondary selections were submitted to the competitive bidding list. In the case of reagent is designated as a singular, we submitted a explanatory statement with the data obtained during the primary and secondary selection processes. Results Excluded from the primary selection was the case where TAT was expected to be delayed at the moment, and it was impossible to apply to our equipment due to the large volume of reagents used during the test. In the primary selection, there were five items which only one reagent was available.(squamous cell carcinoma Ag(SCC Ag), β-human chorionic gonadotropin(β-HCG), vitamin B12, folate, free testosterone), two reagents were available(CA19-9, CA125, CA72-4, ferritin, thyroglobulin antibody(TG Ab), microsomal antibody(Mic Ab), thyroid stimulating hormone-receptor-antibody(TSH-R-Ab), calcitonin), three reagents were available (triiodothyronine(T3), Tree T3, Free T4, TSH, intact parathyroid hormone(intact PTH)) and four reagents were available are carcinoembryonic antigen(CEA), TG. In the secondary selection, there were eight items which only one reagent was available.(ferritin, TG, CA19-9, SCC, β-HCG, vitaminB12, folate, free testosterone), two reagents were available(TG Ab, Mic Ab, TSH-R-Ab, CA125, CA72-4, intact PTH, calcitonin), three reagents were available(T3, Tree T3, Free T4, TSH, CEA). Reasons excluded from the secondary selection were the lack of reagent supply for comparative evaluations, the problems with data reproducibility, and the inability to accept data variations. The most problematic part of comparative evaluations was sample collection. It didn't matter if the number of samples requested was large and the capacity needed for the test was small. It was difficult to collect various concentration samples in the case of a small number of tests(100 cases per month or less), and it was difficult to conduct a recovery rate test in the case of a relatively large volume of samples required for a single test(more than 100 uL). In addition, the lack of dilution solution or standard zero material for sensitivity measurement or dilution tests was one of the problems. Conclusion Comparative evaluation for changing test reagents require appropriate preparation time to collect diverse and sufficient samples. In addition, setting the total sample volume and reagent volume range required for comparative evaluations, depending on the sample volume and reagent volume required for one test, will reduce the burden of sample collection and planning for each comparative evaluation.

The Effects of Consumer Value Cognition on Benefits and Attributes of Culture-Art Products (문화예술상품 소비자의 가치인식이 추구혜택과 상품속성에 미치는 영향)

  • Shin, Eun Joo;Rhee, Young Sun
    • Asia Marketing Journal
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    • v.14 no.2
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    • pp.177-207
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    • 2012
  • Today's consumers perceive consumption as a representation of themselves. It is not simply an act that fulfills a consumer's physical and practical needs. Even in terms of life quality, consumers increasingly want to achieve an emotional and sensible experience through consumption. Consumers now make decisions based on their need to express their position in relation to other people, pursue emotional satisfaction, and try to improve the quality of life. Culture-art products that meet such internal and external demands of consumers have made significant improvements in both quantity and quality, because of the social interest and policy support. The recognition of personal and social values of culture and arts has brought about interest in and need for culture-art products. Businesses have agilely embraced such change and actively implemented various marketing strategies utilizing culture and arts. For example, businesses began to sponsor artists who produce culture-art products while building facilities for cultural and art performances or exhibitions. Businesses have also provided performances and exhibitions free-of-charge or at affordable prices. As a result, the supply in the market has started to exceed its demand as is often the case in many of other markets. However, such imbalance has occurred not because of over-supply but because of a lack of demand. Given these circumstances, the government and culture and art related organizations, which had mainly concentrated on the supply side, started to recognize the importance of creating personal and social values in culture and arts. As a result, the government and various organizations are now creating various strategies that include policy measures to achieve their new found goal. Unfortunately however, such efforts are not meeting the expectations. Focusing on above-mentioned circumstances and problems, this study aims to find measures to create demand for culture-art products in the internal conditions of those who consume culture-art products. In other words, given that the demand for culture-art products has not increased despite all external conditions to encourage consumption, this study aims to find the reasons in consumers' value judgment on culture-art products. Though there were recent studies on culture-art products that applied consumer behavior on marketing theories, most of them focused on peripheral aspects such as people's motivation for or satisfaction from watching culture-art events. Hence, there is a need to understand what kind of value consumers perceive from culture-art products and how such value cognition leads to consumption in a comprehensive manner. This study acts as follow-up to a separate study entitled "Qualitative Study about Value Cognition and Benefits of Consumer on Culture-Art Products". The current study aims to extend practical implications that enhance the effectiveness of marketing strategies among the producing and policy agencies in the industry. The purpose of this study is to investigate dimensions of value cognition, benefits and attributes of culture-art products, and identify the effects of consumer value cognition on benefits and attributes. The questionnaire was developed based on the conceptual structure of qualitative research and previous researches. It was composed of value cognition, benefits, attributes of culture-art products and demographic variables. This survey was conducted on-line and off-line among a total of 662 persons ranging from their teens to their 50's who were living in Seoul, Gyeonggi-do, various metropolitan cities, and small and medium-sized cities. The data collected was analyzed by factor analysis and path analysis using SPSS WIN 18.0 and AMOS 16.0. This empirical study found that the dimensions of value cognition of culture-art products were categorized into personal goods, aesthetic goods and public property. This shows that the consumers perceive culture-art products as products that are worthy enough to pay the costs not just for personal benefits but also for their social values. Also the formation of value cognition for culture-art products requires special conditions unlike that for physical consumer goods and services, which simply require marketing stimuli. The dimensions of benefits pursued by consuming culture-art products were found to be composed of four types - pursuit of aesthetic benefits, pursuit of actual benefits, pursuit of emotional benefits, and pursuit of conspicuous character. This result implies that people consume culture-art products not just to pursue pleasure from emotional and intelligent satisfaction as well as social relations, but also to seek the needs and benefits embodied at a social level. The dimensions of attributes of culture-art products had seven different factors, - environmental, price, evaluation, people, artwork, composition, and personal relations - which is plentiful. This is because the attributes of culture-art products are very complicated compared to other consumer goods or services. Since culture-art products include not just cultural or artistic works but also all physical, human, environmental, and systemic elements of the products in a comprehensive manner, consumers perceive everything they experience in the process of consuming culture-art products as part of the products. The dimensions of value cognition was found to affect attributes of the products, mostly using pursued benefits as a mediating factors. This result is consistent with the result of qualitative research, and proves that applying the means-end chain theory in the reverse direction is reasonable. The result can be interpreted that consumers' value cognitions for culture-art products turns into actual benefits leading to consumers' decisions. Furthermore, this result reveals that when consumers choose culture-art products, they take into account the attributes of culture-art products depending on the benefits they pursue. These results confirm that despite their conceptual and abstract attributes, culture-art products have values that contribute to actual benefits for individual consumers and society. Hence, value cognition generates benefits to be pursued and this in turn affects the consumers' choices of attributes on products. Based on the conceptual structure of consumers' value cognitions on culture-art products and its dimensions, it is possible to find detailed methods to provide opportunities for education and training to form and reinforce positive value cognition on culture-art products. And through those methods, it will be possible to develop attributes of culture-art products according to the dimensions of pursued benefits, and allow conceptual products become the subject to valuable consumption in real life. These results provide theoretical understanding of consumer behavior in culture marketing and useful information to culture-art producers, companies that use culture and art, and government agencies that use culture-art as a mean to improve the public perception of quality of life. As a follow up on this study, there should be experimental studies that can develop criteria visualizing the demands of consumers who purchase culture-art products and identify their detailed attributes. Studies that compare characteristics of different areas within the culture-art product category and in-depth studies on a specific area or genre will also be needed. In order to develop marketing strategies for culture-art products, studies on the formation and reinforcement of positive value cognition on culture-art products and education for the development of consumer demand as well as on the development and differentiation of attributes of culture-art products depending on types of consumer groups should also follow.

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Effects of Reward Programs on Brand Loyalty in Online Shopping Contexts (인터넷쇼핑 상황에서 보상프로그램이 브랜드충성도에 미치는 영향에 관한 연구)

  • Kim, Ji-Hern;Kang, Hyunmo;Munkhbazar, M.
    • Asia Marketing Journal
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    • v.14 no.2
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    • pp.39-63
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    • 2012
  • Previous studies of reward programs have generally focused on designing the best programs for consumers and suggested that consumers' perception of the value of reward programs can vary according to the type of reward program (e.g., hedonic vs. utilitarian and direct vs. indirect) and its timing (e.g., immediate vs. delayed). These studies have typically assumed that consumers' preference for reward programs has a positive effect on brand loyalty. However, Dowling and Uncles (1997) pointed out that this preference does not necessarily foster brand loyalty. In this regard, the present study verifies this assumption by examining the effects of consumers' perception of the value of reward programs on their brand loyalty. Although reward programs are widely used by online shopping malls, most studies have examined the conditions under which consumers are most likely to value loyalty programs in the context of offline shopping. In the context of online shopping, however, consumers' preferences may have little effect on their brand loyalty because they have more opportunities for comparing diverse reward programs offered by many online shopping malls. That is, in online shopping, finding attractive reward programs may require little effort on the part of consumers, who are likely to switch to other online shopping malls. Accordingly, this study empirically examines whether consumers' perception of the value of reward programs influences their brand loyalty in the context of online shopping. Meanwhile, consumers seek utilitarian and/or hedonic value from their online shopping activity(Jones et al., 2006; Barbin et al., 1994). They visit online shopping malls to buy something necessary (utilitarian value) and/or enjoy the process of shopping itself (hedonic value). In this sense, reward programs may reinforce utilitarian as well as hedonic value, and their effect may vary according to the type of reward (utilitarian vs. hedonic). According to Chaudhuri and Holbrook (2001), consumers' perception of the value of a brand can influence their brand loyalty through brand trust and affect. Utilitarian value influences brand loyalty through brand trust, whereas hedonic value influences it through brand affect. This indicates that the effect of this perception on brand trust or affect may be moderated by the type of reward program. Specifically, this perception may have a greater effect on brand trust for utilitarian reward programs than for hedonic ones, whereas the opposite may be true for brand affect. Given the above discussion, the present study is conducted with three objectives in order to provide practical implications for online shopping malls to strategically use reward program for establishing profitable relationship with customers. First, the present study examines whether reward programs can be an effective marketing tool for increasing brand loyalty in the context of online shopping. Second, it investigates the paths through which consumers' perception of the value of reward programs influences their brand loyalty. Third, it analyzes the effects of this perception on brand trust and affect by considering the type of reward program as a moderator. This study suggests and empirically analyzes a new research model for examining how consumers' perception of the value of reward programs influences their brand loyalty in the context of online shopping. The model postulates the following 10 hypotheses about the structural relationships between five constructs: (H1) Consumers' perception of the value of reward programs has a positive effect on their program loyalty; (H2) Program loyalty has a positive effect on brand loyalty; (H3) Consumers' perception of the value of reward programs has a positive effect on their brand trust; (H4) Consumers' perception of the value of reward programs has a positive effect on their brand affect; (H5) Brand trust has a positive effect on program loyalty; (H6) Brand affect has a positive effect on program loyalty; (H7) Brand trust has a positive effect on brand loyalty; (H8) Brand affect has a positive effect on brand loyalty; (H9) Consumers' perception of the value of reward programs is more likely to influence their brand trust for utilitarian reward programs than for hedonic ones; and (H10) Consumers' perception of the value of reward programs is more likely to influence their brand affect for hedonic reward programs than for utilitarian ones. To test the hypotheses, we considered a sample of 220 undergraduate students in Korea (male:113). We randomly assigned these participants to one of two groups based on the type of reward program (utilitarian: transportation card, hedonic: movie ticket). We instructed the participants to imagine that they were offered these reward programs while visiting an online shopping mall. We then asked them to answer some questions about their perception of the value of the reward programs, program loyalty, brand loyalty, brand trust, and brand affect, in that order. We also asked some questions about their demographic backgrounds and then debriefed them. We employed the structural equation modeling (SEM) method with AMOS 18.0. The results provide support for some hypotheses (H1, H3, H4, H7, H8, and H9) while providing no support for others (H2, H5, H6, H10) (see Figure 1). Noteworthy is that the path proposed by previous studies, "value perception → program loyalty → brand loyalty," was not significant in the context of online shopping, whereas this study's proposed path, "value perception → brand trust/brand affect → brand loyalty," was significant. In addition, the results indicate that the type of reward program moderated the relationship between consumers' value perception and brand trust but not the relationship between their value perception and brand affect. These results have some important implications. First, this study is one of the first to examine how consumers' perception of the value of reward programs influences their brand loyalty in the context of online shopping. In particular, the results indicate that the proposed path, "value perception → brand trust/brand affect → brand loyalty," can better explain the effects of reward programs on brand loyalty than existing paths. Furthermore, these results suggest that online shopping malls should place greater emphasis on the type of reward program when devising reward programs. To foster brand loyalty, they should reinforce the type of shopping value that consumers emphasize by providing them with appropriate reward programs. If consumers prefer utilitarian value to hedonic value, then online shopping malls should offer utilitarian reward programs and vice versa.

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The Effect of Mutual Trust on Relational Performance in Supplier-Buyer Relationships for Business Services Transactions (재상업복무교역중적매매관계중상호신임대관계적효적영향(在商业服务交易中的买卖关系中相互信任对关系绩效的影响))

  • Noh, Jeon-Pyo
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.4
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    • pp.32-43
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    • 2009
  • Trust has been studied extensively in psychology, economics, and sociology, and its importance has been emphasized not only in marketing, but also in business disciplines in general. Unlike past relationships between suppliers and buyers, which take considerable advantage of private networks and may involve unethical business practices, partnerships between suppliers and buyers are at the core of success for industrial marketing amid intense global competition in the 21st century. A high level of mutual cooperation occurs through an exchange relationship based on trust, which brings long-term benefits, competitive enhancements, and transaction cost reductions, among other benefits, for both buyers and suppliers. In spite of the important role of trust, existing studies in buy-supply situations overlook the role of trust and do not systematically analyze the effect of trust on relational performance. Consequently, an in-depth study that determines the relation of trust to the relational performance between buyers and suppliers of business services is absolutely needed. Business services in this study, which include those supporting the manufacturing industry, are drawing attention as the economic growth engine for the next generation. The Korean government has selected business services as a strategic area for the development of manufacturing sectors. Since the demands for opening business services markets are becoming fiercer, the competitiveness of the business service industry must be promoted now more than ever. The purpose of this study is to investigate the effect of the mutual trust between buyers and suppliers on relational performance. Specifically, this study proposed a theoretical model of trust-relational performance in the transactions of business services and empirically tested the hypotheses delineated from the framework. The study suggests strategic implications based on research findings. Empirical data were collected via multiple methods, including via telephone, mail, and in-person interviews. Sample companies were knowledge-based companies supplying and purchasing business services in Korea. The present study collected data on a dyadic basis. Each pair of sample companies includes a buying company and its corresponding supplying company. Mutual trust was traced for each pair of companies. This study proposes a model of trust-relational performance of buying-supplying for business services. The model consists of trust and its antecedents and consequences. The trust of buyers is classified into trust toward the supplying company and trust toward salespersons. Viewing trust both at the individual level and the organizational level is based on the research of Doney and Cannon (1997). Normally, buyers are the subject of trust, but this study supposes that suppliers are the subjects. Hence, it uniquely focused on the bilateral perspective of perceived risk. In other words, suppliers, like buyers, are the subject of trust since transactions are normally bilateral. From this point of view, suppliers' trust in buyers is as important as buyers' trust in suppliers. The suppliers' trust is influenced by the extent to which it trusts the buying companies and the buyers. This classification of trust using an individual level and an organization level is based on the suggestion of Doney and Cannon (1997). Trust affects the process of supplier selection, which works in a bilateral manner. Suppliers are actively involved in the supplier selection process, working very closely with buyers. In addition, the process is affected by the extent to which each party trusts its partners. The selection process consists of certain steps: recognition, information search, supplier selection, and performance evaluation. As a result of the process, both buyers and suppliers evaluate the performance and take corrective actions on the basis of such outcomes as tangible, intangible, and/or side effects. The measurement of trust used for the present study was developed on the basis of the studies of Mayer, Davis and Schoorman (1995) and Mayer and Davis (1999). Based on their recommendations, the three dimensions of trust used for the study include ability, benevolence, and integrity. The original questions were adjusted to the context of the transactions of business services. For example, a question such as "He/she has professional capabilities" has been changed to "The salesperson showed professional capabilities while we talked about our products." The measurement used for this study differs from those used in previous studies (Rotter 1967; Sullivan and Peterson 1982; Dwyer and Oh 1987). The measurements of the antecedents and consequences of trust used for this study were developed on the basis of Doney and Cannon (1997). The original questions were adjusted to the context of transactions in business services. In particular, questions were developed for both buyers and suppliers to address the following factors: reputation (integrity, customer care, good-will), market standing (company size, market share, positioning in the industry), willingness to customize (product, process, delivery), information sharing (proprietary information, private information), willingness to maintain relationships, perceived professionalism, authority empowerment, buyer-seller similarity, and contact frequency. As a consequential variable of trust, relational performance was measured. Relational performance is classified into tangible effects, intangible effects, and side effects. Tangible effects include financial performance; intangible effects include improvements in relations, network developing, and internal employee satisfaction; side effects include those not included either in the tangible or intangible effects. Three hundred fifty pairs of companies were contacted, and one hundred five pairs of companies responded. After deleting five company pairs because of incomplete responses, one hundred five pairs of companies were used for data analysis. The response ratio of the companies used for data analysis is 30% (105/350), which is above the average response ratio in industrial marketing research. As for the characteristics of the respondent companies, the majority of the companies operate service businesses for both buyers (85.4%) and suppliers (81.8%). The majority of buyers (76%) deal with consumer goods, while the majority of suppliers (70%) deal with industrial goods. This may imply that buyers process the incoming material, parts, and components to produce the finished consumer goods. As indicated by their report of the length of acquaintance with their partners, suppliers appear to have longer business relationships than do buyers. Hypothesis 1 tested the effects of buyer-supplier characteristics on trust. The salesperson's professionalism (t=2.070, p<0.05) and authority empowerment (t=2.328, p<0.05) positively affected buyers' trust toward suppliers. On the other hand, authority empowerment (t=2.192, p<0.05) positively affected supplier trust toward buyers. For both buyers and suppliers, the degree of authority empowerment plays a crucial role in the maintenance of their trust in each other. Hypothesis 2 tested the effects of buyerseller relational characteristics on trust. Buyers tend to trust suppliers, as suppliers make every effort to contact buyers (t=2.212, p<0.05). This tendency has also been shown to be much stronger for suppliers (t=2.591, p<0.01). On the other hand suppliers trust buyers because suppliers perceive buyers as being similar to themselves (t=2.702, p<0.01). This finding confirmed the results of Crosby, Evans, and Cowles (1990), which reported that suppliers and buyers build relationships through regular meetings, either for business or personal matters. Hypothesis 3 tested the effects of trust on perceived risk. It has been found that for both suppliers and buyers the lower is the trust, the higher is the perceived risk (t=-6.621, p<0.01 for buyers; t=-2.437, p<0.05). Interestingly, this tendency has been shown to be much stronger for buyers than for suppliers. One possible explanation for this higher level of perceived risk is that buyers normally perceive higher risks than do suppliers in transactions involving business services. For this reason, it is necessary for suppliers to implement risk reduction strategies for buyers. Hypothesis 4 tested the effects of trust on information searching. It has been found that for both suppliers and buyers, contrary to expectation, trust depends on their partner's reputation (t=2.929, p<0.01 for buyers; t=2.711, p<0.05 for suppliers). This finding shows that suppliers with good reputations tend to be trusted. Prior experience did not show any significant relationship with trust for either buyers or suppliers. Hypothesis 5 tested the effects of trust on supplier/buyer selection. Unlike buyers, suppliers tend to trust buyers when they think that previous transactions with buyers were important (t=2.913 p<0.01). However, this study did not show any significant relationship between source loyalty and the trust of buyers in suppliers. Hypothesis 6 tested the effects of trust on relational performances. For buyers and suppliers, financial performance reportedly improved when they trusted their partners (t=2.301, p<0.05 for buyers; t=3.692, p<0.01 for suppliers). It is interesting that this tendency was much stronger for suppliers than it was for buyers. Similarly, competitiveness was reported to improve when buyers and suppliers trusted their partners (t=3.563, p<0.01 for buyers; t=3.042, p<0.01 for suppliers). For suppliers, efficiency and productivity were reportedly improved when they trusted buyers (t=2.673, p<0.01). Other performance indices showed insignificant relationships with trust. The findings of this study have some strategic implications. First and most importantly, trust-based transactions are beneficial for both suppliers and buyers. As verified in the study, financial performance can be improved through efforts to build and maintain mutual trust. Similarly, competitiveness can be increased through the same kinds of effort. Second, trust-based transactions can facilitate the reduction of perceived risks inherent in the purchasing situation. This finding has implications for both suppliers and buyers. It is generally believed that buyers perceive higher risks in a highly involved purchasing situation. To reduce risks, previous studies have recommended that suppliers devise risk-reducing tactics. Moving beyond these recommendations, the present study uniquely focused on the bilateral perspective of perceived risk. In other words, suppliers are also susceptible to perceived risks, especially when they supply services that require very technical and sophisticated manipulations and maintenance. Consequently, buyers and suppliers must solve problems together in close collaboration. Hence, mutual trust plays a crucial role in the problem-solving process. Third, as found in this study, the more authority a salesperson has, the more he or she can be trusted. This finding is very important with regard to tactics. Building trust is a long-term assignment; however, when mutual trust has not been developed, suppliers can overcome the problems they encounter by empowering a salesperson with the authority to make certain decisions. This finding applies to suppliers as well.

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Response of Potassium on Main Upland Crops (주요(主要) 전작물(田作物)에 대(對)한 가리성분(加里成分)의 비교(肥效))

  • Ryn, In Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.10 no.3
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    • pp.171-188
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    • 1977
  • The response and effect on main upland crops to potassium were discussed and summarized as follows. 1. Adequate average amounts of potash per 10a were 32kg for forage crop; 22.5kg for vegetable crops; 17.3kg for fruit trees; 13.3kg for potatoes; and 6.5kg for cereal crops. Demand of potassium fertilizer in the future will be increased by expanding the acreage of forage crops, vegetable crops and fruit trees. 2. On the average, optimum potash rates on barley, wheat, soybean, corn, white potato and sweet potato were 6.5, 6.9, 4.5, 8.1, 8.9, and 17.7kg per 10a respectively. Yield increaments per 1kg of potash per 10a were 4-5kgs on the average for cereal crops, 68kg for white potato, and 24kg for sweet potato. 3. According to the soil testing data, the exchangeable potassium in the coastal area was higher than that in the inland area and medium in the mountainous area. The exchangeable potassium per province in decreasing order is Jeju>Jeonnam>Kangweon>Kyongnam. Barley : 4. The response of barley to an adequate rate of potassium seemed to be affected more by differences in climatic conditions than to the nature of the soil. 5. The response and the adequate rate of potassium in the southern area, where the temperature is higher, were low because of more release of potassium from the soil. However, the adequate rate of phosphorus was increased due to the fixation of applied phosphorus into the soil in high temperature regions. The more nitrogen application would be required in the southern area due to its high precipitation. 6. The average response of barley to potassium was lower in the southern provinces than northern provinces. Kyongsangpukdo, a southern province, showed a relatively higher response because of the low exchangeable potassium content in the soil and the low-temperature environment in most of cultivation area. 7. Large annual variations in the response to and adequate rates of potassium on barley were noticed. In a cold year, the response of barley to potassium was 2 to 3 times higher than in a normal year. And in the year affected by moisture and drought damage, the responses to potassium was low but adequate rates was higher than cold year. 8. The content of exchangeable potassium in the soil parent materials, in increasing order was Crystalline Schist, Granite, Sedimentary and Basalt. The response of barley to potash occurred in the opposite order with the smallest response being in Crystalline Schist soil. There was a negative correlation between the response and exchangeable potassium contents but there was nearly no difference in the adequate rates of potassium. 9. Exchangeable potassium according to the mode of soil deposition was Alluvium>Residium>Old alluvium>Valley alluvium. The highest response to potash was obtained in Valley alluvium while the other s showed only small differences in responses. 10. Response and adequate rates of potassium seemed to be affected greatly by differences in soil texture. The response to potassium was higher in Sandy loam and Loam soils but the optimum rate of potassium was higher in Clay and Clay loam. Especially when excess amount of potassium was applied in Sandy loam and Loam soils the yield was decreased. 11. The application of potassium retarded the heading date by 1.7 days and increased the length of culm. the number of spikelet per plant, the 1,000 grain weight and the ratio of grain weight to straw. Soybean : 12. Average response of soybean to potassium was the lowest among other cereal crops but 28kg of grain yield was incrased by applying potash at 8kg/10a in newly reclaimed soils. 13. The response in the parent materials soil was in the order of Basalt (Jeju)>Sedimentay>Granite>Lime stone but this response has very wide variations year to year. Corn : 14. The response of corn to potassium decreased in soils where the exchangeable potassium content was high. However, the optimum rate of applied potassium was increased as the soil potassium content was increased because corn production is proportional to the content of soil potassium. 15. An interaction between the response to potassium and the level of phosphorus was noted. A higher response to potassium and higher rates of applied potassium was observed in soils contained optimum level of phosphorus. Potatoes : 16. White potato had a higher requirement for nitrogen than for potassium, which may imply that potato seems to have a higher capability of soil potassium uptake. 17. The yield of white potato was higher in Sandy loam than in Clay loam soil. Potato yields were also higher in soils where the exchangeable potassium content was high even in the same soil texture. However, the response to applied potassium was higher in Clay loam soils than in Sandy loam soils and in paddy soil than in upland soil. 18. The requirement for nitrogen and phosphorus by sweet potato was relatively low. The sweet potato yield is relatively high even under unfavorable soil conditions. A characteristics of sweet potatoes is to require higher level of potassium and to show significant responses to potassium. 19. The response of sweet potato to potassium varied according to soil texture. Higher yields were obtained in Sandy soil, which has a low exchangeable potassium content, by applying sufficient potassium. 20. When the optimum rate of potassium was applied, the yields of sweet potato in newly reclaimed soil were comparable to that in older upland soils.

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An Analytical Study on the Stem-Growth by the Principal Component and Canonical Correlation Analyses (주성분(主成分) 및 정준상관분석(正準相關分析)에 의(依)한 수간성장(樹幹成長) 해석(解析)에 관(關)하여)

  • Lee, Kwang Nam
    • Journal of Korean Society of Forest Science
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    • v.70 no.1
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    • pp.7-16
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    • 1985
  • To grasp canonical correlations, their related backgrounds in various growth factors of stem, the characteristics of stem by synthetical dispersion analysis, principal component analysis and canonical correlation analysis as optimum method were applied to Larix leptolepis. The results are as follows; 1) There were high or low correlation among all factors (height ($x_1$), clear height ($x_2$), form height ($x_3$), breast height diameter (D. B. H.: $x_4$), mid diameter ($x_5$), crown diameter ($x_6$) and stem volume ($x_7$)) except normal form factor ($x_8$). Especially stem volume showed high correlation with the D.B.H., height, mid diameter (cf. table 1). 3) (1) Canonical correlation coefficients and canonical variate between stem volume and composite variate of various height growth factors ($x_1$, $x_2$ and $x_3$) are ${\gamma}_{u1,v1}=0.82980^{**}$, $\{u_1=1.00000x_7\\v_1=1.08323x_1-0.04299x_2-0.07080x_3$. (2) Those of stem volume and composite variate of various diameter growth factors ($x_4$, $x_5$ and $x_6$) are ${\gamma}_{u1,v1}=0.98198^{**}$, $\{{u_1=1.00000x_7\\v_1=0.86433x_4+0.11996x_5+0.02917x_6$. (3) And canonical correlation between stem volume and composite variate of six factors including various heights and diameters are ${\gamma}_{u1,v1}=0.98700^{**}$, $\{^u_1=1.00000x_7\\v1=0.12948x_1+0.00291x_2+0.03076x_3+0.76707x_4+0.09107x_5+0.02576x_6$. All the cases showed the high canonical correlation. Height in the case of (1), D.B.H. in that of (2), and the D.B.H, and height in that of (3) respectively make an absolute contribution to the canonical correlation. Synthetical characteristics of each qualitative growth are largely affected by each factor. Especially in the case of (3) the influence by the D.B.H. is the most significant in the above six factors (cf. table 2). 3) Canonical correlation coefficient and canonical variate between composite variate of various height growth factors and that of the various diameter factors are ${\gamma}_{u1,v1}=0.78556^{**}$, $\{u_1=1.20569x_1-0.04444x_2-0.21696x_3\\v_1=1.09571x_4-0.14076x_5+0.05285x_6$. As shown in the above facts, only height and D.B.H. affected considerably to the canonical correlation. Thus, it was revealed that the synthetical characteristics of height growth was determined by height and those of the growth in thickness by D.B.H., respectively (cf. table 2). 4) Synthetical characteristics (1st-3rd principal component) derived from eight growth factors of stem, on the basis of 85% accumulated proportion aimed, are as follows; Ist principal component ($z_1$): $Z_1=0.40192x_1+0.23693x_2+0.37047x_3+0.41745x_4+0.41629x_5+0.33454x_60.42798x_7+0.04923x_8$, 2nd principal component ($z_2$): $z_2=-0.09306x_1-0.34707x_2+0.08372x_3-0.03239x_4+0.11152x_5+0.00012x_6+0.02407x_7+0.92185x_8$, 3rd principal component ($z_3$): $Z_3=0.19832x_1+0.68210x_2+0.35824x_3-0.22522x_4-0.20876x_5-0.42373x_6-0.15055x_7+0.26562x_8$. The first principal component ($z_1$) as a "size factor" showed the high information absorption power with 63.26% (proportion), and its principal component score is determined by stem volume, D.B.H., mid diameter and height, which have considerably high factor loading. The second principal component ($z_2$) is the "shape factor" which indicates cubic similarity of the stem and its score is formed under the absolute influence of normal form factor. The third principal component ($z_3$) is the "shape factor" which shows the degree of thickness and length of stem. These three principal components have the satisfactory information absorption power with 88.36% of the accumulated percentage. variance (cf. table 3). 5) Thus the principal component and canonical correlation analyses could be applied to the field of forest measurement, judgement of site qualities, management diagnoses for the forest management and the forest products industries, and the other fields which require the assessment of synthetical characteristics.

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Mineral Nutrition of the Field-Grown Rice Plant -[I] Recovery of Fertilizer Nitrogen, Phosphorus and Potassium in Relation to Nutrient Uptake, Grain and Dry Matter Yield- (포장재배(圃場栽培) 수도(水稻)의 무기영양(無機營養) -[I] 삼요소이용률(三要素利用率)과 양분흡수량(養分吸收量), 수량(收量) 및 건물생산량(乾物生産量)과(乾物生産量)의 관계(關係)-)

  • Park, Hoon
    • Applied Biological Chemistry
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    • v.16 no.2
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    • pp.99-111
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    • 1973
  • Percentage recovery or fertilizer nitrogen, phosphorus and potassium by rice plant(Oriza sativa L.) were investigated at 8, 10, 12, 14 kg/10a of N, 6 kg of $P_2O_5$ and 8 kg of $K_2O$ application level in 1967 (51 places) and 1968 (32 places). Two types of nutrient contribution for the yield, that is, P type in which phosphorus firstly increases silicate uptake and secondly silicate increases nitrogen uptake, and K type in which potassium firstly increases P uptake and secondly P increases nitrogen uptake were postulated according to the following results from the correlation analyses (linear) between percentage recovery of fertilizer nutrient and grain or dry matter yields and nutrient uptake. 1. Percentage frequency of minus or zero recovery occurrence was 4% in nitrogen, 48% in phosphorus and 38% in potassium. The frequency distribution of percentage recovery appeared as a normal distribution curve with maximum at 30 to 40 recovery class in nitrogen, but appeared as a show distribution with maximum at below zero class in phosphorus and potassium. 2. Percentage recovery (including only above zero) was 33 in N (above 10kg/10a), 27 in P, 40 in K in 1967 and 40 in N, 20 in P, 46 in Kin 1968. Mean percentage recovery of two years including zero for zero or below zero was 33 in N, 13 in P and 27 in K. 3. Standard deviation of percentage recovery was greater than percentage recovery in P and K and annual variation of CV (coefficient of variation) was greatest in P. 4. The frequency of significant correlation between percentage recovery and grain or dry matter yield was highest in N and lowest in P. Percentage recovery of nitrogen at 10 kg level has significant correlation only with percentage recovery of P in 1967 and only with that of potassium in 1968. 5. The correlation between percentage recovery and dry matter yield of all treatments showed only significant in P in 1967, and only significant in K in 1968, Negative correlation coefficients between percentage recovery and grain or dry matter yield of no or minus fertilizer plots were shown only in K in 1967 and only in P in 1968 indicating that phosphorus fertilizer gave a distinct positive role in 1967 but somewhat' negative role in 1968 while potassium fertilizer worked positively in 1968 but somewhat negatively in 1967. 6. The correlation between percentage recovery of nutrient and grain yield showed similar tendency as with dry matter yield but lower coefficients. Thus the role of nutrients was more precisely expressed through dry matter yield. 7. Percentage recovery of N very frequently had significant correlation with nitrogen uptake of nitrogen applied plot, and significant negative correlation with nitrogen uptake of minus nitrogen plot, and less frequently had significant correlation with P, K and Si uptake of nitrogen applied plot. 8. Percentage recovery of P had significant correlation with Si uptake of all treatments and with N uptake of all treatments except minus phosphorus plot in 1967 indicating that phosphorus application firstly increases Si uptake and secondly silicate increases nitrogen uptake. Percentage recovery of P also frequently had significant correlation with P or K uptake of nitrogen applied plot. 9. Percentage recovery of K had significant correlation with P uptake of all treatments, N uptake of all treatments except minus phosphorus plot, and significant negative correlation with K uptake of minus K plot and with Si uptake of no fertilizer plot or the highest N applied plot in 1968, and negative correlation coefficient with P uptake of no fertilizer or minus nutrient plot in 1967. Percentage recovery of K had higher correlation coefficients with dry matter yield or grain yield than with K uptake. The above facts suggest that K application firstly increases P uptake and secondly phosphorus increases nitrogen uptake for dry matter yied. 10. Percentage recovery of N had significant higher correlation coefficient with grain yield or dry matter yield of minus K plot than with those of minus phosphorus plot, and had higher with those of fertilizer plot than with those of minus K plot. Similar tendency was observed between N uptake and percentage recovery of N among the above treatments. Percentage recovery of K had negative correlation coefficient with grain or-dry matter yield of no fertilizer plot or minus nutrient plot. These facts reveal that phosphorus increases nitrogen uptake and when phosphorus or nitrogen is insufficient potassium competatively inhibits nitrogen uptake. 11. Percentage recovery of N, Pand K had significant negative correlation with relative dry matter yield of minus phosphorus plot (yield of minus plot x 100/yield of complete plot; in 1967 and with relative grain yield of minus K plot in 1968. These results suggest that phosphorus affects tillering or vegetative phase more while potassium affects grain formation or Reproductive phase more, and that clearly show the annual difference of P and K fertilizer effect according to the weather. 12. The correlation between percentage recovery of fertilizer and the relative yield of minus nutrient plat or that of no fertilizer plot to that of minus nutrient plot indicated that nitrogen is the most effective factor for the production even in the minus P or K plot. 13. From the above facts it could be concluded that about 40 to 50 percen of paddy fields do rot require P or K fertilizer and even in the case of need the application amount should be greatly different according to field and weather of the year, especially in phosphorus.

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