Use of high-resolution upwind scheme for vortical flow simulations

For vortical flow simulations at high Reynolds numbers, it is important to keep the artificial dissipation as small as possible since it induces unphysical decay of the vortex strength. One way to accomplish this is to decrease the grid spacing. Another way is to use computational schemes having little dissipation. Here, one of the high-resolution upwind schemes called MUSCL with Roe's average is applied to vortical flow fields. Two examples are considered. One is the leading-edge separation-vortex flow over a strake-delta wing. The other is a high-angle of attack supersonic flow over a spaceplane-like geometry. Comparison with the central difference solutions indicates that the present upwind scheme is less dissipative and thus has better resolution for the vortical flows

Navier-Stokes simulation of wind-tunnel flow using LU-ADI factorization algorithm

The three dimensional Navier-Stokes solution code using the LU-ADI factorization algorithm was employed to simulate the workshop test cases of transonic flow past a wing model in a wind tunnel and in free air. The effect of the tunnel walls is well demonstrated by the present simulations. An Amdahl 1200 supercomputer having 128 Mbytes main memory was used for these computations

網膜色素上皮細胞ベーサル膜における塩素イオンコンダクタンスの存在証拠

取得学位 : 博士（医学）, 学位授与番号 : 医博乙第1188号, 学位授与年月日：平成4年9月16日,学位授与年：199

Intracellular cAMP contents regulate NAMPT expression via induction of C/EBPβ in adipocytes

A decline in intracellular nicotinamide adenine mononucleotide (NAD+) causes adipose tissue dysfunction. Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step in the NAD+ biosynthesis pathway. However, the molecular mechanism that mediates regulation of NAMPT expression in adipocytes is yet to be elucidated. This study found that intracellular cAMP regulates NAMPT expression and promoter activity in 3T3-L1 adipocytes. cAMP-mediated Nampt promoter activity was suppressed by protein kinase A inhibitor H89, whereas AMP-activated protein kinase inhibitor compound C did not affect cAMP-mediated Nampt promoter activity. Intracellular cAMP induced CCAAT/enhancer-binding protein β (C/EBPβ) expression. Knockdown of C/EBPβ suppressed NAMPT expression and promoter activity. Furthermore, the Nampt promoter was activated by C/EBPβ, while LIP activated the dominant-negative form of C/EBPβ. Promoter sequence analysis revealed that the region from -96 to -76 on Nampt was required for C/EBPβ-mediated promoter activity. Additionally, chromatin immunoprecipitation assay demonstrated that C/EBPβ was bound to the promoter sequences of Nampt. Finally, NAMPT inhibitor FK866 suppressed adipogenesis in 3T3-L1 cells, and this suppressive effect was restored by nicotinamide mononucleotide treatment. These findings showed that intracellular cAMP increased NAMPT levels by induction of C/EBPβ expression and indicated that the induction of NAMPT expression was important for adipogenesis.ArticleBiochemical and Biophysical Research Communications. 522(3): 770-775. (2020)journal articl

Nonylphenol-degrading Microbe

東京水産大学生物資源化学講座東京水産大学生物資源化学講座東京水産大学生物資源化学講

Oxygen radical absorbance capacity (ORAC) of cyclodextrin-solubilized flavonoids, resveratrol and astaxanthin as measured with the ORAC-EPR method

Recently, we proposed an oxygen radical absorbance capacity method that directly quantifies the antioxidant’s scavenging capacity against free radicals and evaluated the radical scavenging abilities for water soluble antioxidant compounds. In this study, we determined the radical scavenging abilities of lipophilic antioxidants which were solubilized by cyclodextrin in water. Commonly employed fluorescence-based method measures the antioxidant’s protection capability for the fluorescent probe, while we directly quantify free-radical level using electron paramagnetic resonance spin trapping technique. In addition, the spin trapping-based method adopted controlled UV-photolysis of azo-initiator for free radical generation, but in fluorescence-based method, thermal decomposition of azo-initiator was utilized. We determined the radical scavenging abilities of seven well-known lipophilic antioxidants (five flavonoids, resveratrol and astaxanthin), using methylated β-cyclodextrin as a solubilizer. The results indicated that the agreement between spin trapping-based and fluorescence-based values was only fair partly because of a large variation in the previous fluorescence-based data. Typical radical scavenging abilities in trolox equivalent unit are: catechin 0.96; epicatechin 0.94; epigallocatechin gallate 1.3; kaempferol 0.37; myricetin 3.2; resveratrol 0.64; and astaxanthin 0.28, indicating that myricetin possesses the highest antioxidant capacity among the compounds tested. We sorted out the possible causes of the deviation between the two methods