• Title/Summary/Keyword: PPARr

Search Result 3, Processing Time 0.02 seconds

Retrieval of oceanic primary production using support vector machines

  • Tang, Shilin;Chen, Chuqun;Zhan, Haigang
    • Proceedings of the KSRS Conference
    • /
    • v.1
    • /
    • pp.114-117
    • /
    • 2006
  • One of the most important tasks of ocean color observations is to determine the distribution of phytoplankton primary production. A variety of bio-optical algorithms have been developed estimate primary production from these parameters. In this communication, we investigated the possibility of using a novel universal approximator-support vector machines (SVMs)-as the nonlinear transfer function between oceanic primary production and the information that can be directly retrieved from satellite data. The VGPM (Vertically Generalized Production Model) dataset was used to evaluate the proposed approach. The PPARR2 (Primary Production Algorithm Round Robin 2) dataset was used to further compare the precision between the VGPM model and the SVM model. Using this SVM model to calculate the global ocean primary production, the result is 45.5 PgC $yr^{-1}$, which is a little higher than the VGPM result.

  • PDF

Gene Expression Profile in Epididymal Adipose Tissue from High-fat Diet Fed Mice (고지방식이를 섭취한 mouse에서의 유전자군의 발현양상 변화)

  • Cha, Min-Ho;Kim, Kyung-Seon;Sim, Woong-Seop;Yoon, Yoo-Sik
    • Korean Journal of Oriental Medicine
    • /
    • v.8 no.2 s.9
    • /
    • pp.75-84
    • /
    • 2002
  • Obesity can be defined as a metabolic disease due to a increased state of fat tissue caused by an imbalance of calorie intake and use. To define genes that affected by different nutrient, we study gene expression from mice which were fed different nutrient. Epididymal and retro-peritineal adipose tissue were increase in high fat diet feeding mice compared with control, but liver and spleen were not. In serum, total cholesterol were differently increase in high fat diet feeding mice but total triglyceride and free fatty acid were not. That was maybe result of energy balance regulation in vivo system. aP2, PPART2 and FAS genes that were increased during adipogenesis were inclosed in high fat diet fed mice compared with control. In microarray assay, 1.4% of total genes were affected in epididymal adipose tissue by different nutrient. 1.1% of total genes were decreased down 0.5 fold and 0.3% were increased over 2 fold. These results indicated that many genes are affected in adipose tissue by nutrient.

  • PDF

Analysis of Lipogenic and Myogenic Gene Expressions in Energy Restricted Broiler Chickens (육계의 에너지 제한 사양에 따른 지방 합성 및 근육 발달 관련 유전자의 발현 양상 비교 분석)

  • Moon, Yang-Soo
    • Korean Journal of Poultry Science
    • /
    • v.36 no.4
    • /
    • pp.301-309
    • /
    • 2009
  • The present study was conducted to determine the effect of energy restricted (ER) diet on the expressions of lipogenic genes in liver and myogenic genes in muscle tissue of broiler chickens. Energy restriction was accomplished by providing chicks with 70% (ER70) or 85% (ER85) energy level of control diet intake. Energy restricted groups of chickens were restricted for 7 days, starting at 8 days of age. Ad libitum feeding was resumed after the restriction period, and continued through the end of the experiment. The body weight of chickens in the restricted groups gained less during the energy restriction period (P<0.05). The body weight of the ER groups were similar to the control group during the re-alimentation period. However, the body weight of the ER70 group did not catch up with that of the control group by 35 days of age. The energy restrictions during early life of chicks decreased the contents of triglycerides and cholesterol in blood (P<0.05), but those were not different among treatments after re-alimentation. The genes of fatty acid synthase (FAS) and transcription factors including SREBP and PPARγ were down regulated by restriction regimen only in ER70 (P<0.05). However, those genes were not completely recovered after re-alimentation in ER70 group. The RNA expression levels of Myo-D, Myf-5 and myogenin in all treatment groups were decreased by restriction regimen when compared with control group (P<0.05). Myogenin was highly expressed after re-alimentation, but the other genes were not different among groups. These results suggest that ER85 group shows the best growth performance by re-alimentation and the higher muscle differentiation by expressing myogenin.