• Title/Summary/Keyword: environmental actions

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Primary cilia in energy balance signaling and metabolic disorder

  • Lee, Hankyu;Song, Jieun;Jung, Joo Hyun;Ko, Hyuk Wan
    • BMB Reports
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    • v.48 no.12
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    • pp.647-654
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    • 2015
  • Energy homeostasis in our body system is maintained by balancing the intake and expenditure of energy. Excessive accumulation of fat by disrupting the balance system causes overweight and obesity, which are increasingly becoming global health concerns. Understanding the pathogenesis of obesity focused on studying the genes related to familial types of obesity. Recently, a rare human genetic disorder, ciliopathy, links the role for genes regulating structure and function of a cellular organelle, the primary cilium, to metabolic disorder, obesity and type II diabetes. Primary cilia are microtubule based hair-like membranous structures, lacking motility and functions such as sensing the environmental cues, and transducing extracellular signals within the cells. Interestingly, the subclass of ciliopathies, such as Bardet-Biedle and Alström syndrome, manifest obesity and type II diabetes in human and mouse model systems. Moreover, studies on genetic mouse model system indicate that more ciliary genes affect energy homeostasis through multiple regulatory steps such as central and peripheral actions of leptin and insulin. In this review, we discuss the latest findings in primary cilia and metabolic disorders, and propose the possible interaction between primary cilia and the leptin and insulin signal pathways which might enhance our understanding of the unambiguous link of a cell's antenna to obesity and type II diabetes.

SPACE-BASED OCEAN SURVEILLANCE AND SUPPORT CAPABILITY

  • Yang Chan-Su
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.253-256
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    • 2005
  • The use of satellite remote sensing in maritime safety and security can aid in the detection of illegal fishing activities and provide more efficient use of limited aircraft or patrol craft resources. In the area of vessel traffic monitoring for commercial vessels, Vessel Traffic Service (VTS) which use the ground-based radar system have some difficulties in detecting moving ships due to the limited detection range. A virtual vessel traffic control system is introduced to contribute to prevent a marine accident such as collision and stranding from happening. Existing VTS has its limit. The virtual vessel traffic control system consists of both data acquisition by satellite remote sensing and a simulation of traffic environment stress based on the satellite data, remotely sensed data. And it could be used to provide timely and detailed information about the marine safety, including the location, speed and direction of ships, and help us operate vessels safely and efficiently. If environmental stress values are simulated for the ship information derived from satellite data, proper actions can be taken to prevent accidents. Since optical sensor has a high spatial resolution, JERS satellite data are used to track ships and extract their information. We present an algorithm of automatic identification of ship size and velocity. This paper lastly introduce the field testing results of ship detection by RADARSAT SAR imagery, and propose a new approach for a Vessel Monitoring System(VMS), including VTS, and SAR combination service.

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Transport of chloride through saturated soil column: An experimental study

  • Patil, S.B.;Chore, H.S.
    • Advances in environmental research
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    • v.4 no.2
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    • pp.105-117
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    • 2015
  • The groundwater is a very important part of the environment and must be protected for the benefit of the present and future generation. The contamination of soil and groundwater by chemicals has become an increasing concern in the recent past. These chemicals enter the groundwater system by a wide variety of mechanisms, including accidental spills, land disposal of domestic and industrial wastes and application of agricultural fertilizers. Once introduced into an aquifer, these contaminants will be transported by flowing groundwater and may degrade water quality at nearby wells and streams. For improving the management and protection of groundwater resources, it is important to first understand the various processes that control the transport of contaminants in groundwater. Predictions of the fate of groundwater contaminants can be made to assess the effect of these chemicals on local water resources and to evaluate the effectiveness of remedial actions. In this study, an attempt has been made to investigate the behaviour of solute transport through porous media using laboratory experiments. Sodium chloride was used as a conservative chemical in the experiment. During the experiment, pulse boundary condition and continuous boundary conditions were used. Experimental results have been presented for conservative solute transport in the sand. The pattern of the break through curve remains almost same in all the cases of varying flow rate and initial concentration of conservative chemical.

Policy Implementation Process of Korean Government's Public Diplomacy on Climate Change

  • Choi, Ga Young;Song, Jaeryoung;Lee, Eunmi
    • Asian Journal of Innovation and Policy
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    • v.9 no.1
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    • pp.1-11
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    • 2020
  • In 2015, the State Council of South Korea finalized its goal to reduce greenhouse gas emissions by "37% from the business-as-usual (BAU) level" by 2030 across all the economic sectors. Of that reduction, 4.5% will be achieved overseas by leveraging Emission Trading Systems (ETS) aided by international cooperation. In line with this, considering both the demand for and supply of the carbon market increased after the Paris agreement, the importance of public diplomacy in negotiating climate change actions also rose. This study aimed to analyze the impact of international discussions such as the United Nations Framework Convention on Climate Change (UNFCCC) on domestic policies and the types of public diplomatic climate change policies pursued by different government agencies, and draw implications from them. This study attempted to find implications from the Korean government's public diplomacy on climate change for developing countries. Lessons learned regarding Korea's public diplomacy would provide a practical guidance to the Asian developing countries, which are suffering from environmental crisis at a phase of rapid economic growth.

On autonomous decentralized evolution of holon network

  • Honma, Noriyasu;Sato, Mitsuo;Abe, Kenichi;Takeda, Hiroshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.498-503
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    • 1994
  • The paper demonstrates that holon networks can be used effectively for identification of nonlinear dynamical systems. The emphasis of the paper is on modeling of complicated systems which have a great deal of uncertainty and unknown interactions between their elements and parameters. The concept of applying a quantitative model building, for example, to environmental or ecological systems is not new. In a previous paper we presented a holon network model as an another alternative to quantitative modeling. Holon networks have a hierarchical construction where each level of hierarchy consists of networks with reciprocal actions among their elements. The networks are able to evolve by self-organizing their structure and adapt their parameters to environments. This was achieved by an autonomous decentralized adaptation algorithm. In this paper we propose a new emergent evolution algorithm. In this algorithm the initial holon networks consists of only a few elements and it grows gradually with each new observation in order to fit their function to the environment. Some examples show that this algorithm can lead to a network structure which has sufficient flexibility and adapts well to the environment.

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Zinc in Pancreatic Islet Biology, Insulin Sensitivity, and Diabetes

  • Maret, Wolfgang
    • Preventive Nutrition and Food Science
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    • v.22 no.1
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    • pp.1-8
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    • 2017
  • About 20 chemical elements are nutritionally essential for humans with defined molecular functions. Several essential and nonessential biometals are either functional nutrients with antidiabetic actions or can be diabetogenic. A key question remains whether changes in the metabolism of biometals and biominerals are a consequence of diabetes or are involved in its etiology. Exploration of the roles of zinc (Zn) in this regard is most revealing because 80 years of scientific discoveries link zinc and diabetes. In pancreatic ${\beta}$- and ${\alpha}$-cells, zinc has specific functions in the biochemistry of insulin and glucagon. When zinc ions are secreted during vesicular exocytosis, they have autocrine, paracrine, and endocrine roles. The membrane protein ZnT8 transports zinc ions into the insulin and glucagon granules. ZnT8 has a risk allele that predisposes the majority of humans to developing diabetes. In target tissues, increased availability of zinc enhances the insulin response by inhibiting protein tyrosine phosphatase 1B, which controls the phosphorylation state of the insulin receptor and hence downstream signalling. Inherited diseases of zinc metabolism, environmental exposures that interfere with the control of cellular zinc homeostasis, and nutritional or conditioned zinc deficiency influence the pathobiochemistry of diabetes. Accepting the view that zinc is one of the many factors in multiple gene-environment interactions that cause the functional demise of ${\beta}$-cells generates an immense potential for treating and perhaps preventing diabetes. Personalized nutrition, bioactive food, and pharmaceuticals targeting the control of cellular zinc in precision medicine are among the possible interventions.

Self-Care in Elders with Dementia: A Concept Analysis

  • Yeom Hye-A
    • Journal of Korean Academy of Nursing
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    • v.34 no.8
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    • pp.1402-1408
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    • 2004
  • Purpose: The purpose of this study was to analyze the concept of self-care in elders with dementia through a review of nursing literature and to provide more understanding of the definition and perspectives of the concept of self-care notion in elders with dementia. Methods: The technique developed by Walker and Avant was used as a guide in analyzing the concept of self-care. Results: Attributes of self-care in dementia may include a single or group of actions needed for sustaining life, a personal effort to maintain functional independence while minimizing other's assistance, an outcome behavior from the person's interaction with inter-personal and/or contextual environment, and a functional ability that may decline in parallel to cognitive impairment. Antecedents of self-care in dementia may include at least presence of a certain degree of cognitive appraisal for the self-care needs, self-willingness for the self-care action, spatial and visual orientation, cultural pre-conception of the self-care behavior, presence of environmental context/equipment available for self-care, and sufficient time available. The consequences may include sustaining of life, feel of satisfaction, achieving independence, extended life expectancy, increased self-confidence, decreased caregiver distress and/or burden, savings in health care costs. Discussion: Defining attributes and antecedents and consequences of self-care in dementia identified in this study provided empirical ground of a middle-range theory of self-care for a clinical population with dementia and generated possible hypotheses to be tested in future studies.

Effect of biaxial stress state on seismic fragility of concrete gravity dams

  • Sen, Ufuk;Okeil, Ayman M.
    • Earthquakes and Structures
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    • v.18 no.3
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    • pp.285-296
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    • 2020
  • Dams are important structures for management of water supply for irrigation or drinking, flood control, and electricity generation. In seismic regions, the structural safety of concrete gravity dams is important due to the high potential of life and economic loss if they fail. Therefore, the seismic analysis of existing dams in seismically active regions is crucial for predicting responses of dams to ground motions. In this paper, earthquake response of concrete gravity dams is investigated using the finite element (FE) method. The FE model accounts for dam-water-foundation rock interaction by considering compressible water, flexible foundation effects, and absorptive reservoir bottom materials. Several uncertainties regarding structural attributes of the dam and external actions are considered to obtain the fragility curves of the dam-water-foundation rock system. The structural uncertainties are sampled using the Latin Hypercube Sampling method. The Pine Flat Dam in the Central Valley of Fresno County, California, is selected to demonstrate the methodology for several limit states. The fragility curves for base sliding, and excessive deformation limit states are obtained by performing non-linear time history analyses. Tensile cracking including the complex state of stress that occurs in dams was also considered. Normal, Log-Normal and Weibull distribution types are considered as possible fits for fragility curves. It was found that the effect of the minimum principal stress on tensile strength is insignificant. It is also found that the probability of failure of tensile cracking is higher than that for base sliding of the dam. Furthermore, the loss of reservoir control is unlikely for a moderate earthquake.

Sensitivity Analysis of the Factors Influencing for Decision of Reinforced Roadbed Thickness (강화노반 두께 결정을 위한 영향인자 민감도 분석)

  • Choi, Chan-Yong;Lee, Jin-Wook;Bae, Jae-Hoon;Shin, Eun-Chul
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1827-1832
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    • 2007
  • The purpose of a railway track is to provide a smooth surface for safe and economical train transportation. The performance of the track results from a complex interaction of the track and subgrade components in response to train loading and environmental actions. In the past, the role of subgrade as the track foundation were not recognized adequately. There are insufficient information and inadequate methods for subgrade design, assessment and improvement. This situation has survived for a long time largely because a subgrade defect can often be adjusted by adding more ballast under the ties or applying more frequent track maintenance. Therefore, the application of reinforced roadbed technology will be expected to increase in the future. The reinforced roadbed thickness is set depending on subgrade reaction modulus$(K_{30})$ in the condition of upper subgrade through PBT in both conventional railroad and KTX railroads. As train velocity (V), train passing tonnage (N), and train axial load (P) are not considered in design, the roadbed thickness could be overestimated (or underestimated). Therefore, In this study, the computer model, GEOTRACK, was analyzed the influence of reinforced roadbed thickness factors on track modulus and the characteristics of stress pulses in track and subgrade generated by repeated axle loading.

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Determination Method of Reinforced Roadbed Thickness based on Design Chart (설계지표를 이용한 철도강화노반 두께 산정에 관한 연구)

  • Yoo, Chung-Hyun;Choi, Chan-Yong;Kim, Dae-Sang
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1279-1286
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    • 2007
  • The purpose of a railway track is to provide a smooth surface for safe and economical train transportation. The performance of the track results from a complex interaction of the track and subgrade components in response to train loading and environmental actions. In the past, the role of subgrade as the track foundation were not recognized adequately. There are insufficient information and inadequate methods for subgrade design, assessment and improvement. This situation has survived for a long time largely because a subgrade defect can often be adjusted by adding more ballast under the ties or applying more frequent track maintenance. Therefore, the application of reinforced roadbed technology will be expected to increase in the future. The reinforced roadbed thickness is set depending on subgrade reaction modulus($K_{30}$) in the condition of upper subgrade through PBT in both conventional railroad and KTX railroads. As train velocity (V), train passing tonnage (N), and train axial load (P) are not considered in design, the roadbed thickness could be overestimated (or underestimated). Therefore, in this study has proposed a determination method of reinforced roadbed thickness using design chart made by resilience modulus and properties of earthwork materials.

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