Refined numerical simulation in wind resource assessment

Cheng, Xue-Ling,Li, Jun,Hu, Fei,Xu, Jingjing,Zhu, Rong Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.20 No.1

A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

Refined numerical simulation in wind resource assessment

Xue-Ling Cheng,Jun Li,Fei Hu,Jingjing Xu,Rong Zhu 한국풍공학회 2015 Wind and Structures, An International Journal (WAS Vol.20 No.1

A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

Substituent Effect on the Structure and Biological Property of 99mTc-Labeled Diphosphonates: Theoretical Studies

Ling Qiu,Jian-Guo Lin,Xue-Dong Gong,Wen Cheng,Shi-Neng Luo 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

Theoretical calculations based on density functional theory (DFT) were performed to study the substituent effect on the geometric and electronic structures as well as the biological behavior of technetium-99m-labeled diphosphonate complexes. Optimized structures of these complexes are surrounded by six ligands in an octahedral environment with three unpaired 4d electrons (d3 state) and the optimized geometry of 99mTc-MDP agrees with experimental data. With the increase of electron-donating substituent or tether between phosphate groups, the energy gap between frontier orbitals increases and the probability of non-radiative deactivation via d-d electron transfer decreases. The charge distribution reflects a significant ligand-to-metal electron donation. Based on the calculated geometric and electronic structures and biologic properties of 99mTc-diphosphonate complexes, several structure-activity relationships (SARs) were established. These results may be instructive for the design and synthesis of novel 99mTc-diphosphonate bone imaging agent and other 99mTc-based radiopharmaceuticals.

Substituent Effect on the Structure and Biological Property of ^99mTc-Labeled Diphosphonates: Theoretical Studies

Qiu, Ling,Lin, Jian-Guo,Gong, Xue-Dong,Cheng, Wen,Luo, Shi-Neng Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

Theoretical calculations based on density functional theory (DFT) were performed to study the substituent effect on the geometric and electronic structures as well as the biological behavior of technetium-99m-labeled diphosphonate complexes. Optimized structures of these complexes are surrounded by six ligands in an octahedral environment with three unpaired 4d electrons ($d^3$ state) and the optimized geometry of $^{99m}Tc$-MDP agrees with experimental data. With the increase of electron-donating substituent or tether between phosphate groups, the energy gap between frontier orbitals increases and the probability of non-radiative deactivation via d-d electron transfer decreases. The charge distribution reflects a significant ligand-to-metal electron donation. Based on the calculated geometric and electronic structures and biologic properties of $^{99m}Tc$-diphosphonate complexes, several structure-activity relationships (SARs) were established. These results may be instructive for the design and synthesis of novel $^{99m}Tc$-diphosphonate bone imaging agent and other $^{99m}Tc$-based radiopharmaceuticals.

Identification of a Novel Streptomyces chattanoogensis L10 and Enhancing Its Natamycin Production by Overexpressing Positive Regulator ScnRII

Yi-Ling Du,Shi-Fei Chen,Liang-Ying Cheng,Xue-Ling Shen,Yuan Tian,Yong-Quan Li 한국미생물학회 2009 The journal of microbiology Vol.47 No.4

A novel Streptomyces strain, L10, which is capable of producing natamycin, was isolated from a soil sample collected from Zhejiang province, China. On the basis of phylogenetic analysis of rpoB gene and 16S rDNA sequences, as well as phenotypic comparison, strain L10 (CGMCC 2644) is proposed to be a previously uncharacterized strain of S. chattanoogensis. By screening a cosmid library of strain L10 and primer walking, a partial sequence of scnRI and the entire sequence of scnRII were obtained, which are orthologues to the pathway-specific positive regulator genes of natamycin biosynthesis in S. natalensis. The engineered S. chattanoogensis D1, generated by inserting an additional copy of scnRII into the chromosome of strain L10, increased its natamycin production by 3.3 fold in YSG medium and 4.6 fold in YEME medium without sucrose.

The most energetic modes of thermal structure in the convective boundary layer

Lei Liu,Fei Hu,Xue-ling Cheng 한국기상학회 2011 한국기상학회 학술대회 논문집 Vol.2011 No.10-2

Effect of structural phase transformations under pressure on electronic and optical properties of CuInS2

Bo Gao,Hong-Tao Xue,Fu-Ling Tang,Yu-Wen Cheng 한국물리학회 2017 Current Applied Physics Vol.17 No.11

First-principles plane-wave calculations were employed to study the phase transitions, electronic and optical properties of chalcopyrite CuInS2 (CIS) under pressure, which is a promising semiconductor compound material for nonlinear optical, photovoltaic and bio-applications. From the variations of Gibbs free energy and volume with pressure, we confirmed an experimentally found phase transformation of CIS from tetragonal I42d structure into the cubic Fm3m phase. It occurs at 7.9 GPa with a volume reduction of 15.6%, which are comparable with the experimental values of 9.5 GPa and 12%. A new possible phase transition of CIS from the cubic Fm3m structure to the orthorhombic Cmcm structure under higher pressure was predicted occurring at 49.6 GPa with a volume reduction about 0.64%. Using the more accurate HSE06 functional, we found that the growth rate of energy gap with pressure (dEg/dP) for the I42d phase is about 24.8 meV/GPa, very close to the experimental value of 24 meV/GPa. The calculated electronic properties for Fm3m and Cmcm phases show that CIS is a metallic material under high pressure, rather than a semiconductor. The optical absorption spectra indicate that with the increase of pressure the absorption edge of CIS becomes smaller while the optical energy gap is larger.

Comparative Phylogenetic Relationships and Genetic Structure of the Caterpillar Fungus Ophiocordyceps sinensis and Its Host Insects Inferred from Multiple Gene Sequences

Qing-Mei Quan,Qing-Xia Wang,Xue-Li Zhou,Shan Li,Xiao-Ling Yang,Yun-Guo Zhu,Zhou Cheng 한국미생물학회 2014 The journal of microbiology Vol.52 No.2

Ophiocordyceps sinensis (Ascomycota: Ophiocordycipitaceae)is a native fungal parasite of Hepialidae caterpillars and oneof the most economically important medicinal caterpillarfungi in China. However, little is known about the phylogeneticand evolutionary relationships between O. sinensis andits host insects. In this study, nuclear ITS and β-tubulin sequencesfrom O. sinensis and mitochondrial COI, COII, andCytb sequences from its hosts were analyzed across 33 populationssampled from five regions in China. Phylogenetically,both O. sinensis and its hosts were divided into three geographicallycorrelated clades, and their phylogenies were congruent. Analysis of molecular variance and calculated coefficientsof genetic differentiation revealed significant geneticdivergence among the clades within both O. sinensis (FST=0.878, NST=0.842) and its hosts (FST=0.861, NST=0.816). Estimatedgene flow was very low for O. sinensis (Nm=0.04) andthe host insects (Nm=0.04) among these three clades. Manteltests demonstrated a significant correlation (P<0.01) betweenthe genetic distances for O. sinensis and its hosts, as well as asignificant association (P<0.05) between geographic and geneticdistances in both. The similar phylogenetic relationships,geographic distributions, and genetic structure and differentiationbetween O. sinensis and its hosts imply that they have coevolved.

The Beneficial Effects of Dietary Astragali Radix Are Related to the Regulation of Gut Microbiota and Its Metabolites

Zhi Chai,Zhen-Yu Li,Ling Wang,Lan Yang,Xiao-Ling Cheng,Xue-Mei Qin 한국식품영양과학회 2024 Journal of medicinal food Vol.27 No.1

Astragali Radix (AR) or its extract has been used as an herbal medicine and dietary supplement in China,Europe, and the United States. The gut microbiota could provide new insights for exploring dietary supplements’ underlyingmechanism on organisms. However, no reports have focused on the regulatory effect of AR on the gut microbiota as a dietarysupplement. In this study, healthy ICR mice of either sex were divided into AR and control (CON) groups and given AR waterextract (4.55 mg/kg$day-1) or saline by gavage for 14 days, respectively. Then 16S rRNA gene sequencing and ultra-highperformanceliquid chromatography quadrupole time-of-flight tandem mass spectrometry-based fecal metabolomics wereintegrated to investigate the benefits of dietary AR. Weighted gene coexpression network analysis was also introduced toinvestigate the metabolites with highly synergistic changes. AR supplementation influenced the structure of intestinal microflora,especially enriching short-chain fatty acid-producing bacteria g_Coprobacillus, g_Prevotella, and g_Parabacteroides. AR also significantly altered the fecal metabolome, mainly related to amino acid metabolism, nucleotidemetabolism, and bile acid (BA) metabolism. Moreover, the increased secondary BAs and BA-sulfates might closely relate tointestinal microflora. These findings provide valuable insights for future research of dietary AR as a functional food.

4-Hydroxynonenal Promotes Growth and Angiogenesis of Breast Cancer Cells through HIF-1α Stabilization

Li, Yao-Ping,Tian, Fu-Guo,Shi, Peng-Cheng,Guo, Ling-Yun,Wu, Hai-Ming,Chen, Run-Qi,Xue, Jin-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

4-Hydroxynonenal (4-HNE) is a stable end product of lipid peroxidation, which has been shown to play an important role in cell signal transduction, while increasing cell growth and differentiation. 4-HNE could inhibit phosphatase and tensin homolog (PTEN) activity in hepatocytes and increased levels have been found in human invasive breast cancer. Here we report that 4-HNE increased the cell growth of breast cancer cells as revealed by colony formation assay. Moreover, vascular endothelial growth factor (VEGF) expression was elevated, while protein levels of hypoxia inducible factor 1 alpha (HIF-$1{\alpha}$) were up-regulated. Sirtuin-3 (SIRT3), a major mitochondria NAD+-dependent deacetylase, is reported to destabilize HIF-$1{\alpha}$. Here, 4-HNE could inhibit the deacetylase activity of SIRT3 by thiol-specific modification. We further demonstrated that the regulation by 4-HNE of levels of HIF-$1{\alpha}$ and VEGF depends on SIRT3. Consistent with this, 4-HNE could not increase the cell growth in SIRT3 knockdown breast cancer cells. Additionally, 4-HNE promoted angiogenesis and invasion of breast cancer cells in a SIRT3-dependent manner. In conclusion, we propose that 4-HNE promotes growth, invasion and angiogenesis of breast cancer cells through the SIRT3-HIF-$1{\alpha}$-VEGF axis.