• Title/Summary/Keyword: gamma model

Search Result 1,197, Processing Time 0.029 seconds

Dependence of Geomagnetic Storms on Their Assocatied Halo CME Parameters

  • Lee, Jae-Ok;Moon, Yong-Jae;Lee, Kyoung-Sun;Kim, Rok-Soon
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.37 no.1
    • /
    • pp.95.2-95.2
    • /
    • 2012
  • We have compared the geoeffective parameters of halo coronal mass ejections (CMEs) to predict geomagnetic storms. For this we consider 50 front-side full halo CMEs whose asymmetric cone model parameters and earthward direction parameter were available. For each CME we use its projected velocity (Vp), radial velocity (Vr), angle between cone axis and sky plane (${\gamma}$) from the cone model, earthward direction parameter (D), source longitude (L), and magnetic field orientation (M) of the CME source region. We make a simple and multiple linear regression analysis to find out the relationship between CME parameters and Dst index. Major results are as follows. (1) $Vr{\times}{\gamma}$ has a higher correlation coefficient (cc = 0.70) with the Dst index than the others. When we make a multiple regression of Dst and two parameters ($Vr{\times}{\gamma}$, D), the correlation coefficient increases from 0.70 to 0.77. (2) Correlation coefficients between Dst index and $Vr{\times}{\gamma}$ have different values depending on M and L. (3) Super geomagnetic storms (Dst ${\leq}$ -200 nT) only appear in the western and southward events. Our results demonstrate that not only the cone model parameters together with the earthward direction parameter improve the relationship between CME parameters and Dst index but also the source longitude and its magnetic field orientation play a significant role in predicting geomagnetic storms.

  • PDF

Genetic Relationship of Mono-cotyledonous Model Plant by Ionizing Irradiation (단자엽 모델 식물의 방사선원 별 처리에 따른 유전적 다형성 분석)

  • Song, Mira;Kim, Sun-Hee;Jang, Duk-Soo;Kang, Si-Yong;Kim, Jin-Baek;Kim, Sang Hoon;Ha, Bo-Keun;Kim, Dong Sub
    • Journal of Radiation Industry
    • /
    • v.6 no.1
    • /
    • pp.23-29
    • /
    • 2012
  • In this study, we investigated the genetic variation in the general of monocot model plant (rice) in response to various ionizing irradiations including gamma-ray, ion beam and cosmic-ray. The non-irradiated and three irradiated (200 Gy of gamma-ray and 40 Gy of ion beam and cosmic-ray) plants were analyzed by AFLP technique using capillary electrophoresis with ABI3130xl genetic analyzer. The 29 primer combinations tested produced polymorphism results showing a total of 2,238 bands with fragments sizes ranged from 30 bp to 600 bp. The number of polymorphism generated by each primer combinations was varied significantly, ranging from 2 (M-CAC/E-ACG) to 158 (M-CAT/E-AGG) with an average of 77 bands. Polymorphic peaks were detected as 1,269 with an average of 44 per primer combinations. By UPGMA (Unweighted Pair Group Method using Arithmetic clustering) analysis method, the clusters were divided into non-irradiated sample and three irradiated samples at a similarity coefficient of 0.41 and three irradiation samples was subdivided into cosmic-ray and two irradiation samples (200 Gy of gamma-ray and 40 Gy of ion beam) at similarity coefficient of 0.48. Similarity coefficient values ranged from 0.41 to 0.55.

HaCaT Keratinocytes and Primary Epidermal Keratinocytes Have Different Transcriptional Profiles of Cornified Envelope-Associated Genes to T Helper Cell Cytokines

  • Seo, Min-Duk;Kang, Tae-Jin;Lee, Chang-Hoon;Lee, Ai-Young;Noh, Min-Soo
    • Biomolecules & Therapeutics
    • /
    • v.20 no.2
    • /
    • pp.171-176
    • /
    • 2012
  • HaCaT cells are the immortalized human keratinocytes and have been extensively used to study the epidermal homeostasis and its pathophysiology. T helper cells play a role in various chronic dermatological conditions and they can affect skin barrier homeostasis. To evaluate whether HaCaT cells can be used as a model cell system to study abnormal skin barrier development in various dermatologic diseases, we analyzed the gene expression profile of epidermal differentiation markers of HaCaT cells in response to major T helper (Th) cell cytokines, such as $IFN{\gamma}$, IL-4, IL-17A and IL-22. The gene transcriptional profile of cornified envelope-associated proteins, such as filaggrin, loricrin, involucrin and keratin 10 (KRT10), in HaCaT cells was generally different from that in normal human keratinocytes (NHKs). This suggests that HaCaT cells have a limitation as a model system to study the pathophysiological mechanism associated with the Th cell cytokine-dependent changes in cornified envelope-associated proteins which are essential for normal skin barrier development. In contrast, the gene transcription profile change of human ${\beta}2$-defensin (HBD2) in response to $IFN{\gamma}$, IL-4 or IL-17A in HaCaT cells was consistent with the expression pattern of NHKs. $IFN{\gamma}$ also up-regulated transglutaminase 2 (TGM2) gene transcription in both HaCaT cells and NHKs. As an alternative cell culture system for NHKs, HaCaT cells can be used to study molecular mechanisms associated with abnormal HBD2 and TGM2 expression in response to $IFN{\gamma}$, IL-4 or IL-17A.

Effect of High-Molecular-Weight Poly-$\gamma$-Glutamic Acid from Bacillus subtilis (chungkookjang) on Ca Solubility and Intestinal Absorption

  • PARK CHUNG;CHOI YOON-HO;SHIN HYUN-JIN;POO HARYOUNG;SONG JAE JUN;KIM CHUL-JOONG;SUNG MOON-HEE
    • Journal of Microbiology and Biotechnology
    • /
    • v.15 no.4
    • /
    • pp.855-858
    • /
    • 2005
  • The bioavailability of Ca is currently one of the most important topics in nutrition research and is correlated with gastrointestinal solubility. Thus, to increase the solubility of calcium, this study was undertaken to examine the effect of $\gamma$-PGA on intestinal Ca solubility. The calcium solubility increased when the amount of $\gamma$-PGA was increased, due to the inhibition of the formation of an insoluble Ca complex with phosphate. Therefore, when $\gamma$-PGA-500 (avg. MW 5,000 kDa) was added at 0.5 mg/ml, $75\%$ of the total Ca was soluble. The amount of soluble Ca uptake in the small intestine was investigated using Balb/c mice as an animal model system. The soluble Ca uptake in the mice orally administered with $\gamma$-PGA-500 (avg. MW 5,000 kDa) was significantly higher than that in the $\gamma$-PGA-l00 (avg. MW 1,000 kDa)-administered mice (P<0.05). Accordingly, these results strongly support the notion that the molecular size of $\gamma$-PGA is correlated with Ca solubility. The effects of other factors, such as casein phosphopeptide and vitamin D, on intestinal Ca absorption have also previously been investigated. Therefore, it is hoped that the present observations will help clarify the role of $\gamma$-PGA in Ca solubility and its industrial application as an additive.

Effects of HyangsosanGamibang on the $PPAR{\gamma}$ in the bronchial asthma mouse model (천식 백서(喘息 白鼠)에서 향소산가미방(香蘇散加味方)의 $PPAR{\gamma}$에 대한 효과)

  • Park, Eun-Jung;Lee, Hai-Ja;Oh, Ji-Eun
    • The Journal of Pediatrics of Korean Medicine
    • /
    • v.21 no.1
    • /
    • pp.41-51
    • /
    • 2007
  • 목적 : OVA에 유도된 천식 쥐 모델에 향소산가미방을 투여한 후 $PPAR{\gamma}$의 변화를 조사하여 향소산가미방의 천식 치료 기전을 알아보고자 하였다. 대상 및 방법 : 8주된 암컷 BALB/c 마우스에 첫 날과 14일 후에 20 ${\mu}g$의 OVA를 알루미니윰 하이드록사이드 1mg과 혼합한 후 총 200 ${\mu}g$를 복강 내로 주입하여 감작시켰다. 처음 감작시킨 날로부터 21,22,23일 후에 천식 모델에 사용하는 초음파 분무기를 이용하여 세 번째 감작시켜서 천식 마우스 모델을 만들었다. 천식 마우스 모델을 만드는 기간 중 OVA를 복강 내로 주입한 후 19일째에 24시간의 간격으로 향소산가미방을 7일 동안 경구 투여하여 향소산가미방의 효과를 조사하였다. 기관지폐포세척술은 마지막 감작 후 72시간 후에 실행하고 기관지폐포 세척액의 총 세포수를 측정하였다. $PPAR{\gamma}$의 발현은 천식 마우스 모델의 폐와 향소산가미방을 투여한 마우스 모델의 폐를 적출한 후 Western blotting 방법을 아용하여 측정하였다. 병리 조직학적 검사는 hematoxylin 2 and eosin-Y 염색을 이용하여 조사하였다. 결과 : 정상 군과 비교하여 OVA감작 천식 쥐 모델에서는 72시간 후에 총 세포 수가 증가하였다. 특히 OVA감작 천식 군에서 증가된 호산구의 수가 향소산가미방을 투여 한 쥐 군에서는 유의하게 감소하였다. OVA감작 천식 쥐 모델에서 72시간 후에 정상 군과 비교하여 핵 내에서의 $PPAR{\gamma}$단백질의 발현이 약간 증가하였다. 그러나 향소산가미방을 투여한 쥐 모델에서는 세포질과 핵 내에서 $PPAR{\gamma}$단백질의 발현이 유의하게 증가하였다. 조직학적 검사상 정상 군과 비교하여 OVA 감작된 천식 쥐 모델에서는 폐포, 세기관지, 기도내강 주변에 많은 염증 세포들이 있었다. 그러나 가미향소산 을 투여 한 후에는 염증 세포들이 유의하게 감소하였다. 결론 : 가미향소산은 $PPAR{\gamma}$작용제로서 역할을 하며, 천식에 대한 치료제 또는 예방제를 개발하는 데 후보 물질이 될 것으로 사료된다.

  • PDF

Convergence Study of Influence of Nursing Information Literacy Competency on Problem Solving Ability, Self-Directed Learning Ability and Clinical Performance Ability in Nursing Students (간호대학생의 간호정보활용역량이 문제해결능력, 자기주도적 학습능력 및 임상수행능력에 미치는 영향에 대한 융합적 연구)

  • Jo, Mean Jung;Gu, Mee Ock
    • Journal of the Korea Convergence Society
    • /
    • v.9 no.12
    • /
    • pp.495-507
    • /
    • 2018
  • This study was done to develop and validate a path model for the causal relationship of nursing information literacy competency and problem solving, self-direct learning, and clinical performance ability of nursing students. Subject were 208 nursing students in the fourth grade of nursing school. Data were collected from June 4 to June 18, 2018. The nursing information literacy competency of nursing students showed direct effects on problem solving ability (${\gamma}=.70$, p<.001) and direct effects on self-directed learning ability (${\gamma}=.53$, p<.001). Nursing information literacy competency showed direct (${\gamma}=.31$, p<.001) and indirect effects (${\gamma}=.31$, p=.007) on clinical performance ability. These variables explained for 46.2% of clinical performance ability. Therefore, it is recommended to develop an education program that can enhance the nursing information literacy competency for improving the problem solving, self-directed learning, and clinical performance ability of nursing students.

A Study on the Calculation of Heat Release Rate to Compensate the Error due to Single Zone Assumption in Diesel Engines (단일 영역 모델 열발생율 계산 방법의 개선에 관한 연구)

  • Kim Ki-Doo;Yoon Wook-Hyeon;Ha Ji-Soo;Ryu Seung-Hyup
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.28 no.7
    • /
    • pp.1063-1071
    • /
    • 2004
  • Accurate heat release analysis of cylinder pressure data is important for evaluating performance in the development of diesel engine However, traditional single zone first law heat release model(SZM) has significant limitations due to the simplified assumption of uniform charge and neglecting local temperature inside cylinder during combustion process. In this study. heat release rate based on single zone heat release model has been evaluated by comparison with computational analysis results using Fire code which is based on multi-dimensional model(MDM). To overcome limitations due to simplicity of single zone assumption. especially the influence of specific heat ratio on gross heat release has been esteemed and newly suggested were the equation $\gamma$= $\gamma$(${T/T}_{max}$) which describes the variations of gases thermodynamic properties with mean temperature and maximum mean temperature inside cylinder Single zone heat release model applied with this equation is shown to give very good results over whole range of operating conditions when compared with computational analysis results based on multi-dimensional model.

A Review of Dose-response Models in Microbial Risk Assessment (미생물 위해성 평가의 용량-반응 모델에 대한 고찰)

  • 최은영;박경진
    • Journal of Food Hygiene and Safety
    • /
    • v.19 no.1
    • /
    • pp.19-24
    • /
    • 2004
  • Dose-response models in microbial risk assessment can be divided into biologically plausible models and empirical models. Biologically plausible models are formed by the assumptions in dose distribution of microbes, host sensitivity to microbes, and minimal infectious dose of microbes : there are Exponential model and $\beta$-Poisson model, representatively. Empirical models are mainly used to express the toxicity of chemicals : there are Weibull-Gamma model etc. Deviance function (Y) is used to fit available data to dose-response models, and some dose-response models for food-borne pathogens are developed in humans and experimental animals.

A Bayesian Approach for Record Value Statistics Model Using Nonhomogeneous Poisson Process

  • Kiheon Choi;Hee chual Kim
    • Communications for Statistical Applications and Methods
    • /
    • v.4 no.1
    • /
    • pp.259-269
    • /
    • 1997
  • Bayesian inference for a record value statistics(RVS) model of nonhomogeneous Poisson process is considered. We seal with Bayesian inference for double exponential, Gamma, Rayleigh, Gumble RVS models using Gibbs sampling and Metropolis algorithm and also explore Bayesian computation and model selection.

  • PDF