• Title/Summary/Keyword: density dependent

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Embedded Object-Oriented Micromagnetic Frame (OOMMF) for More Flexible Micromagnetic Simulations

  • Kim, Hyungsuk;You, Chun-Yeol
    • Journal of Magnetics
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    • v.21 no.4
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    • pp.491-495
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    • 2016
  • We developed an embedded Object-Oriented Micromagnetic Frame (OOMMF) script schemes for more flexible simulations for complex and dynamic mircomagnetic behaviors. The OOMMF can be called from any kind of softwares by system calls, and we can interact with OOMMF by updating the input files for next step from the output files of the previous step of OOMMF. In our scheme, we set initial inputs for OOMMF simulation first, and run OOMMF for ${\Delta}t$ by system calls from any kind of control programs. After executing the OOMMF during ${\Delta}t$, we can obtain magnetization configuration file, and we adjust input parameters, and call OOMMF again for another ${\Delta}t$ running. We showed one example by using scripting embedded OOMMF scheme, tunneling magneto-resistance dependent switching time. We showed the simulation of tunneling magneto-resistance dependent switching process with non-uniform current density using the proposed framework as an example.

Clinical Applications of Dual-Energy CT

  • Saira Hamid;Muhammad Umer Nasir;Aaron So;Gordon Andrews;Savvas Nicolaou;Sadia Raheez Qamar
    • Korean Journal of Radiology
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    • v.22 no.6
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    • pp.970-982
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    • 2021
  • Dual-energy CT (DECT) provides insights into the material properties of tissues and can differentiate between tissues with similar attenuation on conventional single-energy imaging. In the conventional CT scanner, differences in the X-ray attenuation between adjacent structures are dependent on the atomic number of the materials involved, whereas in DECT, the difference in the attenuation is dependent on both the atomic number and electron density. The basic principle of DECT is to obtain two datasets with different X-ray energy levels from the same anatomic region and material decomposition based on attenuation differences at different energy levels. In this article, we discuss the clinical applications of DECT and its potential robust improvements in performance and postprocessing capabilities.

Increase in $Na^+-Ca^{2+}$ Exchange Activity in Sarcolemma Isolated from Mesenteric Arteries of Spontaneously Hypertensive Rats

  • Lee, Shin-Woong;Lee, Jeung-Soo;Park, Young-Joo;Park, In-Sook
    • Archives of Pharmacal Research
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    • v.12 no.2
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    • pp.128-134
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    • 1989
  • $Na^+-Ca^{2+}$ exchange process in sarcolemmal vesicles isolated from mesenteric arteries of Wistar-Kyoto normotensive(WKY) and spontaneously hypertensive rats(SHR) was investigated. The sarcolemmal fractions isolated after homogenization and sucrose density gradient centrifugation were enriched with 5'-nucleotidase and ouabain sensitive, $K^+-dependent$ phosphatase activities. When the vesicles were loaded with $Na^+$, a time dependent $Ca^{2+}$ uptake was observed. However, very little $Ca^{2+}$ uptake was observed when the vesicles were loaded with $K^+$, or $Ca^{2+}$ uptake of the $Na^+-loaded$ vesicles was carried out in high sodium medium so that there was no sodium gradient. When the vesicles loaded with $Ca^{2+}$ by $Na^+-Ca^{2+}$ exchange were diluted into potassium medium containing EGTA, $Ca^{2+}$ was rapidly released from the vesicles. $Na^+-dependent\;Ca^{2+}$ uptake was increased in SHR compared to WKY, but passive efflux of preaccumulated $Ca^{2+}$ from the vesicles was decreased in SHR. The data indicate that the membrane vesicles of rat mesenteric arteries exhibit $Na^+-Ca^{2+}$ exchange activity. It is also suggested that changes of this process in vascular smooth muscle cell membrane of SHR may be involved in higher intracellular $Ca^{2+}$ concentration and higher basal tone in SHR.

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A Review on Current Studies on Community Attachment and Its Related Variables (지역사회 친밀도의 최근 연구와 관련변인 고찰)

  • Park, Kyong-Cheol;Kim, Sung-Soo
    • Journal of Agricultural Extension & Community Development
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    • v.8 no.2
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    • pp.201-208
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    • 2001
  • The purpose of this study was to review the current studies on community attachment and its related variables to suggest directions for community attachment studies in Korea. Specific objectives of the study were to search the current studies on community attachment, to search for the significant variables related to community attachment, and to draw implications for community development in Korea. The major findings of the study were as follows; 1) Current studies on community attachment used individual characteristic variables such as length of residence in the community, age, size of population and density as major independent variables. 2) Studies on community attachment used community participation, social and cultural environment as major dependent variables, however, both independent variables and dependent variables were used interchangeably in many cases. 3) Recent studied on community attachment employed community economic and cultural variables, however, studies on community attachment in Korea was relatively limited in terms of quantity as well as quality. 4) Further research on community attachment should be conducted by utilizing various independent and dependent variables in various communities to increase the community attachment in rural and urban communities to further strengthen community development in Korea.

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Decision-Making Model Research for the Calculation of the National Disaster Management System's Standard Disaster Prevention Workforce Quota : Based on Local Authorities

  • Lee, Sung-Su;Lee, Young-Jai
    • Journal of Information Technology Applications and Management
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    • v.17 no.3
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    • pp.163-189
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    • 2010
  • The purpose of this research is to develop a decision-making model for the calculation of the National Disaster Management System's standard prevention workforce quota. The final purpose of such model is to support in arranging a rationally sized prevention workforce for local authorities by providing information about its calculation in order to support an effective and efficient disaster management administration. In other words, it is to establish and develop a model that calculates the standard disaster prevention workforce quota for basic local governments in order to arrange realistically required prevention workforce. In calculating Korea's prevention workforce, it was found that the prevention investment expenses, number of prevention facilities, frequency of flood damage, number of disaster victims, prevention density, and national disaster recovery costs have positive influence on the dependent variable when the standard prevention workforce was set as the dependent variable. The model based on the regression analysis-which consists of dependent and independent variables-was classified into inland mountainous region, East coast region, Southwest coastal plain region to reflect regional characteristics for the calculation of the prevention workforce. We anticipate that the decision-making model for the standard prevention workforce quota will aid in arranging an objective and essential prevention workforce for Korea's basic local authorities.

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Aluminum Inhibits Vitellogenin Production via Toxic Effects on Hepatocytes in the Rockfish Sebastes schlegelii

  • Hwang, Un-Ki;Kang, Han-Seung;Lee, Yoon;Shon, Jae-Kyoung
    • Fisheries and Aquatic Sciences
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    • v.14 no.4
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    • pp.355-361
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    • 2011
  • Effects of aluminum (Al) on plasma vitellogenin (VTG), alkaline-labile phosphorus (ALPP), calcium (Ca), glutamate pyruvate transaminase (GPT), the hepatosomatic index (HSI), and hepatic Al concentration were examined in estradiol-$17{\beta}$ ($E_2$)-administered immature rockfish Sebastes schlegeli. Fish were injected intraperitoneally with $E_2$ (5 mg/kg body weight [BW]) and/or Al (0, 0.1, 1, 5, and 10 mg/kg BW) and plasma and liver samples were extracted 7 days later. After sodium dodecyl sulfate polyacrylamide gel electrophoresis, the relative amount of VTG was determined by integrated optical density. VTG accounted for 23.6% of the total proteins in the control group, but this value decreased with increasing Al administration. Al reduced the concentrations of ALPP and Ca in a concentration-dependent manner and significant reduction occurred at Al concentrations greater than 5 mg/kg. The concentration of GPT increased in a concentration-dependent manner in all Al-administered rockfish. The concentrations of Al in the liver also increased, and HSI was decreased, in a concentration-dependent manner. These results suggest that Al inhibits $E_2$-induced VTG production by being toxic to hepatocytes in marine fish.

Mechanisms of Time-dependent Plastic Deformation of Eutectoid and Hypereutectoid Steels at Low T/Tm Temperatures (저 T/Tm 온도에서 공석강 및 과공석강의 시간의존성 소성변형 기구)

  • Choi, B.H.;Chung, K.C.;Park, K.T.
    • Transactions of Materials Processing
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    • v.25 no.6
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    • pp.359-365
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    • 2016
  • The rate-controlling mechanisms for time-dependent plastic deformation of eutectoid and hyper-eutectoid pearlitic steels at low $T/T_m$ temperatures were explored. The strain rate - stress data obtained from a series of constant load tensile tests at $0.25{\sim}0.30T/T_m$ were applied to the power law, the lattice friction controlled plasticity, and the obstacle controlled plasticity. Of these models, the obstacle controlled plasticity was found to best-describe the rate-controlling mechanism for time-dependent plastic deformation of two steels at low $T/T_m$ temperatures in terms of the activation energy for overcoming the obstacles against dislocation glide in ferrite. The deformed microstructures revealed the dislocation forests of a high density as the main obstacles. In addition, the obstacle controlled plasticity well-explained the effects of cementite on the $0^{\circ}K$ flow stress of two steels.

The Effect of Serum and Tramsferrin on the Growth of Malassezia pachydermatis in vitro (In vitro에서의 Malassezia pachydermatis의 성장에 대한 혈청과 Transferrin의 억제효과)

  • 김진영
    • Journal of Veterinary Clinics
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    • v.19 no.1
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    • pp.86-91
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    • 2002
  • The inhibitory effect of pooled canine serum on the growth of ten strains of Malassezia pachydermatis in vitro was investigated. Studies were also carried out to observe the effect of different concentrations of unsaturated bovine transferrin on Malassezia growth in vitro. Ten strains of Malassezia pachygedrmatis in normal canine serum (11.1%, 44.4%) were found to significantly inhibit the growth (p<0.0005) not only in a dose dependent but also in a time dependent manner. The same strains of yeast treated with 1, 2, 4 and 8 times the normal value of serum transferrin (3.0 mg/ml, 6.0 mg/ml, 12.0 mg/ml, 24.0 mg/fl), were shown to have significantly lower OD readings (p<0.05) when compared to yeast treated in lower concentrations of transferrin (1.5 mg/ml). The optical density (OD) of the ten strains of yeast were significantly lower (p<0.005) when treated with various concentrations of transferrin than with the saline control except at 72 hours post incubation. These results indicate that serum has inhibitory effects on Malassezia pachydermatis growth in vitro, and transfferin is one of the components that contribute towards this inhibitory role. The inhibitions are dose and time dependent.

A Bioeconomic Analysis on the Effectiveness of Marine Protected Area (MPA) (MPA 효과에 대한 생물경제학적 분석)

  • Kim, Dohoon
    • Environmental and Resource Economics Review
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    • v.13 no.4
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    • pp.657-684
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    • 2004
  • This study is a theoretical bioeconomic analysis to analyze the effectiveness of Marine Protected Area (MPA) implemented in different stock spatial distributions: Closed System, Source-Sink System, and Density-dependent System. In the analysis, an economic impact of vessel activities is also included and a joint effectiveness of MPA and input control is investigated as well. Results of the analysis show that total fisheries stocks are increased in all systems. However, total harvests are decreased when MPA is implemented in the closed system and in the sink patch of source-sink system. On the contrary, total harvests are increased or decreased according to the rate of stock migration and the level of fisheries stocks in the source patch of source-sink system and in the density-dependent system. Specifically, total harvests are increased more significantly as the rate of migration increases and the level of stock increases higher. In addition, the increase in fishing efforts is restricted due to the increase in fishing cost. Therefore, fishing efforts could not be increased greatly in the fishable area. When input control is combined with MPA, the total stocks could be more increased.

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Effects of Curcuma longa L. on Some Kinds of Cancer Cells (강황이 수종의 암세포에 미치는 영향)

  • Yoon, Joo-Ho;Kim, Jin-Sung;Yoon, Sang-Hyub;Ryu, Bong-Ha
    • The Journal of Internal Korean Medicine
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    • v.27 no.2
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    • pp.429-443
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    • 2006
  • Objectives : The Purpose of this study was to identify anti-tumor effects of Curcuma longa L. on some kinds of cancer cells through molecular biologic methods. Materials & Methods : We used 4 kinds of cancer cell lines such as glioma cells(A172), cervical cancer cells(HeLa), Prostate cancer cells(PC3), lung cancer cells(A549). We injected the boiled extract of Curcuma longa L. $5{\mu}g,\;10{\mu}g$ to culture media(ml) for 24 hours. We measured the cytotoxic effect on 4 kinds of cancer cells through trypan blue exclusion test and the suppressive effect on viability of 4 kinds of cancer cells via MTT assay. We measured the change of mitochondria membrane potential via flow cytometry. The quantitative RT-PCR was used to examine the effect on the revelation of Bcl-2 and Bax which genes are related to apoptosis. We examined the effect on the revelation of Bcl-2 protein and Bax protein by western blot analysis. Results: 1. Extract of Curcuma longa L. showed significant cytotoxic effect on A172, HeLa, PC3 compared to the control group with density dependent manner. 2. Extract of Curcuma longs L. showed significant suppressive effect on viability of A172, HeLa, PC3 compared to the control group with density dependent manner. 3. Curcuma longs L. induced apoptosis by decreasing the membrane potential of mitochondria in A172, HeLa, PC3. 4. In the test about the revelation of genes related to apoptosis, the revelation of Bcl-2 decreased and the revelation of Bax increased in A172. HeLa, PC3 treated with Curcuma longa L. with density dependent manner. 5. In the test about the revelation of protein related to apoptosis, the protein levels of Bcl-2 decreased and the protein levels of Bax increased in A172, HeLa, PC3 treated with Curcuma longa L. Conclusions: This experiment shewed that Curcuma longs L. has anti-tumor effect on glioma, cervical, Prostate cancer cells except on lung cancer. We hope that anti-tumor effects of Curcuma longa L. will be more Practically identified.

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