• Title/Summary/Keyword: natural direct and indirect effects

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Structural Equation Modeling on Nursing Productivity of Nurses in Korea (간호생산성 영향요인 구조모형 분석)

  • Kim, Se Young;Kim, Eun-Kyung;Lim, Heon Man;Lee, Mi Young;Park, Kwang-Ok;Lee, Kyoung A
    • Journal of Korean Academy of Nursing
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    • v.43 no.1
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    • pp.20-29
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    • 2013
  • Purpose: The purpose of this study was to propose and test a predictive model that could explain and predict nursing productivity. Methods: A survey using a structured questionnaire was conducted with 360 nurses in Korea. The data were analyzed using SPSS Windows 18.0 and AMOS 19.0 program. Results: Based on the constructed model, burnout and organizational commitment were found to have direct effects on nurses' turnover intention and nursing productivity. While nursing work environment was found to have indirect effects on nurses' turnover intention and nursing productivity. Conclusion: This structural equational model is a comprehensive theoretical model that explains the related factors and their relationship with nursing productivity. Comprehensive organizational interventions to improve nursing productivity should focus on improving the nursing work environment. Findings from this study can be used to design appropriate strategies to decrease nurse turnover in Korea. Further studies are needed to prospectively verify these causal relationships with larger samples.

A Economic Effects of Fish Seed Release (수산종묘방류사업의 경제성 평가)

  • Hwang Jin-Wook;Lee Kwon-Hyuk;Jeong Dal-Sang;Kim Kwang-Soo
    • The Journal of Fisheries Business Administration
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    • v.36 no.1 s.67
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    • pp.121-138
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    • 2005
  • This study was conducted to investigate the economic effect of the release of seed flounder to the central area of the West Sea, which was analyzed into both direct and indirect effects. The results showed that based on the data collected from partial area, the economic effect of flounder seed release reached 6.97 times, average catch proportion was 32.27$\%$, and recapture rate was 11.26$\%$, suggesting that economic effect was very high. In addition, it was observed that the recapture rate was greatly higher than 2.05$\%$, that of Break-Even-Point. It was noted that the increased catch by the release of seed flounder resulted in the increase in commission of sales and the increase in sports fishing. Another economic effect observed were diverse including the increase in income of fishing village, elevated spirit to proper management of fisheries resources, maintaining of willingness to live in fishing village through activation of local fishing village, prevention of illegal fishing including capture of juvenile fish, and the increase in the supply of sea food of high quality. It is emphasized that although the investigation was conducted in the same area, the results will vary by size at release, time at release and other factors. Finally, there is a need to expand species and area of study for more active economic analysis incorporating natural sciences.

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An Analysis of Social Carrying Capacity in Natural Park (자연공원의 사회적 수용능력 분석 - 국립공원과 도립공원을 대상으로 -)

  • 배민기;장병문
    • Journal of the Korean Institute of Landscape Architecture
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    • v.30 no.6
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    • pp.79-97
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    • 2003
  • The purpose of this paper is to analyze a causal model determining social carrying capacity(SCC) in natural parks, to answer the research question: What is the mechanism for determining SCC in natural parks (NP)\ulcorner After reviewing the literature on SCC and recreation activities in Korean natural parks, we constructed a conceptual framework and formulated the hypothesis of this research. We obtained data through a questionnaire which surveyed 487 visitors at 6 of the 73 NP in Korea during 2001, based on a stratified sampling method. We analyzed the data using descriptive statistical methods, the mean difference test, Pearson's correlation analysis, and path analysis method. We found that 1) The direct effect of resources, activity space(AS), visitor's expectation(VE), encounter, crowding, damage of resources(DR), maintenance condition of resources and facility(MCRF) to SCC are 3.45, 3.62, 2.75, 2.72, 1.32, and 4.77 times more important than that of crowding, respectively, while the indirect effect of resources, AS, VE, encounter, and DR to SCC is 13.03, 11.19, 3.34, 1.3, 2.05, 1.10, 0.05 and 2.30 times more important then that of crowding, respectively, 2) Causal effects of resources, facility, AS, VE, number of visitors(NV), encounter, crowding, VM, DR, and MCRF to SCC turned out to have 0.3523, 0.3321, 0.1751, 0.1465, 0.0307, 0.0762, 0.0604, -0.0510, -0.1177 and 0.2165, respectively, and 3) The causal effect of activity base(AB) and activity atmosphere(AA) to SCC turned out to have 2.57 and 1.1 times higher than that of MCRF, respectively. The research results suggest that 1) this conceptual framework is highly useful for the development of substantive theory and methodology; 2) management issues of AA and MCRF turned out to have 0.81 times in SCC that of AB, i.e, SCC can be significantly improved from control of AA and MCRF; and 3) supply of excellent resources and convenient facilities is needed to increase social carrying capacity. It is recommended that more empirical studies be performed in the future according to the season, visitor characteristics, and AS by NP.

The Injured Starfish Extract Inhalation Effects of Anti-inflammation and Anti-oxidants Enzyme during Indirect Cigarette Smoking (손상된 불가사리 추출물 흡입이 흡연으로 인한 항염증과 항산화 효소의 효과)

  • Hwang, Kyung Hee;Jung, Hyuk;Chang, Su Chan;Park, Jong Seok;Kim, You Young
    • KSBB Journal
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    • v.27 no.6
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    • pp.367-374
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    • 2012
  • Cigarette smoking (SM) is considered to be well known environmental toxin which contributes to the onset of various diseases. SM cause direct lungs damage, activate lungs inflammatory responses, and in some cases leads to the development of lung cancer. Cytokines in injured starfish (Asterina pectinifera) is the potential changes in its expression during the regeneration process. Especially, expression of TGF-${\beta}1$ has increased in arm cut starfish extract after eight days. Also, starfish including saponin like the ginseng. Saponin is widely used in the world because of some effective pharmacological activities. Therefore, the current study was designed to elucidate the pharmacological activities of starfish extract against cigarette smoking induced damage in cell line and pulmonary tissue. We investigate that the effect of eight days starfish extract after arm cut (8d) and intact starfish extract on cell line and mouse lung injury by SM. In cell proliferation analysis, although cigarette smoking extract (CSE) was co-treated, the higher proliferation ability is shown in 8d treatment than intact starfish extract. 8d and intact starfish extract was directly transported to pulmonary cells through respiratory organ by nebulizer inhalation. In this case of cigarette smoking, the pulmonary structure was damaged and functions become abnormal. However, 8d treated groups showed similar with the control group compared with SM group. Among them, 8d was proved to be more effective than intact starfish extract. These results demonstrate that 8d could more protect pulmonary structure and function than intact starfish extract against cigarette smoking by ginseng like saponin and regulation of inflammatory cytokines.

Effects of Wax Gourd Extracts on Adipocyte Differentiation and Uncoupling Protein Genes(Ucps) Expression in 3T3-Ll Preadipocytes

  • Kang, Keun-Jee;Kwon, So-Young
    • Nutritional Sciences
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    • v.6 no.3
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    • pp.148-154
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    • 2003
  • Although various raw plant materials have been demonstrated to exert anti-obesity effects to a greater or lesser extent in both humans and animals when they are used to supplement the diet, it has not been shown extensively that they influence adipocyte cell differentiation involving lipid metabolic gene expressions. Using a well-established 3T3-L1 preadipocyte differentiation system, we decided to look into molecular and cellular event occurring during adipocyte differentiation when raw plant materials aye included in the process, in an effort to demonstrate the potential use of a screening system to define the functions of traditionally well-known materials. To these ends, the effects of ethanol (EtOH) or EtOH/distilled water (DW) extracts of Wax Gourd were examined using cytochemical and molecular analyses to determine whether components of the extracts modulate adipocyte differentiation of 3T3-Ll preadipocytes in vitro. The cytochemical results demonstrated that EtOH or EtOH/DW extracts did not affect lipid accumulation and cell proliferation, although the degree of lipid accumulation was influenced slightly depending on the extract. EtOH extract was highly effective in apoptotic induction during differentiation of 3T3-Ll preadipocytes (p<0.05). Reverse transcription-polymerase chain reaction (RT-PCR) analysis of lipoprotein lipase (LPL), Uncoupling protein (Ucp) 2, 3 and 4 also showed that while LPL expression was not influenced, Ucp2, 3 and 4 were up regulated in the EtOH extract-treated group and down regulated in the EtOH/DW extract-treated group. These changes in gene expressions suggest that the components in different fractions of Wax Gourd extracts may modulate lipid metabolism by either direct or indirect action. Taking these results together, it was concluded that molecular and cellular analyses of adipocyte differentiation involving lipid metabolic genes should facilitate understanding of cellular events occurring during adipocyte differentiation. Furthermore, the experimental scheme and analytical methods used in this study should provide a screening system for the functional study of raw plant materials in obesity research.

The Basic Theories for Restoration of Fragmented Habitats (파편화된 서식처 복원을 위한 기초이론 고찰)

  • Kim, Myoung-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.2
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    • pp.52-61
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    • 2001
  • At least, there are intense pressures on the natural habitats from various disturbance, including urbanization, extension of industrial area, and road construction. These human land use result in fragmentation of landscape and natural habitat. The ecological consequences of habitat fragmentation include the direct effects of habitat loss and the indirect effects of reduced inter-patch dispersal. The decline of biological diversity has been rapidly declined by the habitat loss and fragmentation. Conservation strategists should consider not only the habitat amount of that must be preserved, but also the spatial configuration of habitat across the landscape. But, the paucity of available data for most species forces landscape ecologists to develop the concept, model, and theory. The developed theories are often misused in academic papers and practical applications. The development history, presumption of concept, model, theory is ignored. This tendency have leaded to failure of landscape restoration and the use of theory in conservation practice have come under increasing attacks. This paper will highlight the ecological theory that have proven the most influential in landscape ecology, restoration and conservation : the theory of island biogeography, the theory of nested subset analysis, minimum viable population(MVP), the theory of metapopulation dynamics. And, it find the problem and usefulness of four theory in application to real world. Consequently, the understanding of theoretical implication about landscape ecological theory is required. We must carefully apply the theory after examining the problem and availability of various theory because of no existence of only one general theory.

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A Comparative Research on the Reconstruction and Remodeling of Low-rise, Dilapidated Apartment Buildings (노후저층 공동주택의 재건축과 리모델링 사업의 비교 연구)

  • 이효진;김동훈;김진호;임남기
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2002.05a
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    • pp.75-80
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    • 2002
  • The purpose of this study is to conduct researches on the aspects of reconstruction and remodeling of low-rise, dilapidated apartment buildings in the provinces, using comparative methodologies, consequently coming up with the findings in the following. 1) Unlike the rebuilding projects in which the movement process tends to be made in a bulk (in a simultaneous manner), it turns out that when it comes to remodeling, it would be advisable to attempt moving the inhabitants as a group either by the size of their residence or by the building. 2) Given the peculiarities of the construction management mechanism, remodeling projects might seem disadvantageous on the part of the management on account of inadequate accumulation of information and experience. Hence, based on the impeccable assessment of the current status of the subject buildings from the phase of planning, its imperative to closely look into and take into consideration a variety of direct and/or indirect factors in advance of the implementation. 3) A series of comparative researches from the perspective of economical efficiency that remodeling projects appear profitable considering the overall costs including financial expenses, varied taxes, and so on that will be eventually brought forth during the reconstruction period, and all the more so when allowing for the consequential effects which they ought to have upon the natural and human resources, environmental and ecological condition, business potentials, etc. Amelioration to be desired on the basis of the findings above.

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A Study on Startups' Dependence on Business Incubation Centers (창업보육서비스에 따른 입주기업의 창업보육센터 의존도에 관한 연구)

  • Park, JaeSung;Lee, Chul;Kim, JaeJon
    • Korean small business review
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    • v.31 no.2
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    • pp.103-120
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    • 2009
  • As business incubation centers (BICs) have been operating for more than 10 years in Korea, many early stage startups tend to use the services provided by the incubating centers. BICs in Korea have accumulated the knowledge and experience in the past ten years and their services have been considerably improved. The business incubating service has three facets : (1) business infrastructure service, (2) direct service, and (3) indirect service. The mission of BICs is to provide the early stage entrepreneurs with the incubating service in a limited period time to help them grow strong enough to survive the fierce competition after graduating from the incubation. However, the incubating services sometimes fail to foster the independence of new startup companies, and raise the dependence of many companies on BICs. Thus, the dependence on BICs is a very important factor to understand the survival of the incubated startup companies after graduation from BICs. The purpose of this study is to identify the main factors that influence the firm's dependence on BICs and to characterize the relationships among the identified factors. The business incubating service is a core construct of this study. It includes various activities and resources, such as offering the physical facilities, legal service, and connecting them with outside organizations. These services are extensive and take various forms. They are provided by BICs directly or indirectly. Past studies have identified various incubating services and classify them in different ways. Based on the past studies, we classify the business incubating service into three categories as mentioned above : (1) business infrastructure support, (2) direct support, and (3) networking support. The business infrastructure support is to provide the essential resources to start the business, such as physical facilities. The direct support is to offer the business resources available in the BICs, such as human, technical, and administrational resources. Finally, the indirect service was to support the resource in the outside of business incubation center. Dependence is generally defined as the degree to which a client firm needs the resources provided by the service provider in order to achieve its goals. Dependence is generated when a firm recognizes the benefits of interacting with its counterpart. Hence, the more positive outcomes a firm derives from its relationship with the partner, the more dependent on the partner the firm must inevitably become. In business incubating, as a resident firm is incubated in longer period, we can predict that her dependence on BICs would be stronger. In order to foster the independence of the incubated firms, BICs have to be able to manipulate the provision of their services to control the firms' dependence on BICs. Based on the above discussion, the research model for relationships between dependence and its affecting factors was developed. We surveyed the companies residing in BICs to test our research model. The instrument of our study was modified, in part, on the basis of previous relevant studies. For the purposes of testing reliability and validity, preliminary testing was conducted with firms that were residing in BICs and incubated by the BICs in the region of Gwangju and Jeonnam. The questionnaire was modified in accordance with the pre-test feedback. We mailed to all of the firms that had been incubated by the BICs with the help of business incubating managers of each BIC. The survey was conducted over a three week period. Gifts (of approximately ₩10,000 value) were offered to all actively participating respondents. The incubating period was reported by the business incubating managers, and it was transformed using natural logarithms. A total of 180 firms participated in the survey. However, we excluded 4 cases due to a lack of consistency using reversed items in the answers of the companies, and 176 cases were used for the analysis. We acknowledge that 176 samples may not be sufficient to conduct regression analyses with 5 research variables in our study. Each variable was measured through multiple items. We conducted an exploratory factor analysis to assess their unidimensionality. In an effort to test the construct validity of the instruments, a principal component factor analysis was conducted with Varimax rotation. The items correspond well to each singular factor, demonstrating a high degree of convergent validity. As the factor loadings for a variable (or factor) are higher than the factor loadings for the other variables, the instrument's discriminant validity is shown to be clear. Each factor was extracted as expected, which explained 70.97, 66.321, and 52.97 percent, respectively, of the total variance each with eigen values greater than 1.000. The internal consistency reliability of the variables was evaluated by computing Cronbach's alphas. The Cronbach's alpha values of the variables, which ranged from 0.717 to 0.950, were all securely over 0.700, which is satisfactory. The reliability and validity of the research variables are all, therefore, considered acceptable. The effects of dependence were assessed using a regression analysis. The Pearson correlations were calculated for the variables, measured by interval or ratio scales. Potential multicollinearity among the antecedents was evaluated prior to the multiple regression analysis, as some of the variables were significantly correlated with others (e.g., direct service and indirect service). Although several variables show the evidence of significant correlations, their tolerance values range between 0.334 and 0.613, thereby demonstrating that multicollinearity is not a likely threat to the parameter estimates. Checking some basic assumptions for the regression analyses, we decided to conduct multiple regression analyses and moderated regression analyses to test the given hypotheses. The results of the regression analyses indicate that the regression model is significant at p < 0.001 (F = 44.260), and that the predictors of the research model explain 42.6 percent of the total variance. Hypotheses 1, 2, and 3 address the relationships between the dependence of the incubated firms and the business incubating services. Business infrastructure service, direct service, and indirect service are all significantly related with dependence (β = 0.300, p < 0.001; β = 0.230, p < 0.001; β = 0.226, p < 0.001), thus supporting Hypotheses 1, 2, and 3. When the incubating period is the moderator and dependence is the dependent variable, the addition of the interaction terms with the antecedents to the regression equation yielded a significant increase in R2 (F change = 2.789, p < 0.05). In particular, direct service and indirect service exert different effects on dependence. Hence, the results support Hypotheses 5 and 6. This study provides several strategies and specific calls to action for BICs, based on our empirical findings. Business infrastructure service has more effect on the firm's dependence than the other two services. The introduction of an additional high charge rate for a graduated but allowed to stay in the BIC is a basic and legitimate condition for the BIC to control the firm's dependence. We detected the differential effects of direct and indirect services on the firm's dependence. The firms with long incubating period are more sensitive to indirect service positively, and more sensitive to direct service negatively, when assessing their levels of dependence. This implies that BICs must develop a strategy on the basis of a firm's incubating period. Last but not least, it would be valuable to discover other important variables that influence the firm's dependence in the future studies. Moreover, future studies to explain the independence of startup companies in BICs would also be valuable.

Anti-dementia Effects of Gouteng-san and Si-Wu-Tang

  • Watanabe, Hiroshi
    • Toxicological Research
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    • v.17
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    • pp.257-261
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    • 2001
  • Recently, a traditional medicine called Gouteng-san, which consists of eleven herbs, was reported to be effective in treating vascular dementia with a double-blind, placebo-controlled study. Gout-eng-san is also used for patients with vascular dementia in combination with Si-Wu-Tang. The effect of Gouteng-san and Si-Wu-Tang on deficit of learning behavior was investigated using step-down passive avoidance task in mice. Hot-water extract of Gouteng-san (1.5 and 6 g/kg, p.o.) significantly prolonged the step-down latency shortened by scopolamine. The extract of Uncaria hook (150 mg/kg, p.o.), one of the component herb of Gouteng-san, significantly prevented the decrease in the latency after scopolamine. Hot-water extract of Si-Wu-Tang (1.5 and 6 g/kg of dried herbs, p.o.) prevented dose-dependently scopola-mine-induced disruption qf learning behavior. Si-Wu-Tang also prevented the ischemia-induced deficit of learning behavior. Both hot water extract of peony and angelica (1.5 g/kg, p.o.), which are component herbs qf Si-Wu-Tang, prevented the scopolamine-induced learning behavior deficit. Scopolamine (10 uM) suppressed long-term potentiation (LTP) of population spike in the CA1 region of the rat hippocampal slices. Peoniflorin (0.1~ 1uM) extracted from paeony root significantly ameliorated scopolamine-induced inhibition of LTR These results suggest that improvement of deficit of learning behavior by Gouteng-san and Si-Wu-Tang is mediated by direct and/or indirect activation of the cholinergic system in the brain.

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Effects of temperature on the growth and ingestion rates of the newly described mixotrophic dinoflagellate Yihiella yeosuensis and its two optimal prey species

  • Kang, Hee Chang;Jeong, Hae Jin;Lim, An Suk;Ok, Jin Hee;You, Ji Hyun;Park, Sang Ah;Lee, Sung Yeon;Eom, Se Hee
    • ALGAE
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    • v.35 no.3
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    • pp.263-275
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    • 2020
  • Water temperature is known to affect the growth and feeding of marine dinoflagellates. Each dinoflagellate species grows well at a certain optimal temperature but dies at very cold and hot temperatures. Thus, changes in water temperatures driven by global warming and extremely high or low temperatures can affect the distribution of dinoflagellates. Yihiella yeosuensis is a mixotrophic dinoflagellate that can feed on only the cryptophyte Teleaulax amphioxeia and the chlorophyte Pyramimonas sp. Furthermore, it grows fast mixotrophically but rarely grows photosynthetically. We explored the direct and indirect effects of water temperature on the growth and ingestion rates of Y. yeosuensis feeding on T. amphioxeia and the growth rates of T. amphioxeia and Pyramimonas sp. under 7 different water temperatures (5-35℃). Both the autotrophic and mixotrophic growth rates of Y. yeosuensis on T. amphioxeia were significantly affected by temperature. Under the mixotrophic and autotrophic conditions, Y. yeosuensis survived at 10-25℃, but died at 5℃ and ≥30℃. The maximum mixotrophic growth rate of Y. yeosuensis on T. amphioxeia (1.16 d-1) was achieved at 25℃, whereas the maximum autotrophic growth rate (0.16 d-1) was achieved at 15℃. The maximum ingestion rate of Y. yeosuensis on T. amphioxeia (0.24 ng C predator-1 d-1) was achieved at 25℃. The cells of T. amphioxeia survived at 10-25℃, but died at 5 and ≥30℃. The cells of Pyramimonas sp. survived at 5-25℃, but died at 30℃. The maximum growth rate of T. amphioxeia (0.72 d-1) and Pyramimonas sp. (0.75 d-1) was achieved at 25℃. The abundance of Y. yeosuensis is expected to be high at 25℃, at which its two prey species have their highest growth rates, whereas Y. yeosuensis is expected to be rare or absent at 5℃ or ≥30℃ at which its two prey species do not survive or grow. Therefore, temperature can directly or indirectly affect the population dynamics and distribution of Y. yeosuensis.