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Open access

Hongtao Gao and Biao Li

Abstract

Floating-type wave energy converter has the advantages of high wave energy conversion efficiency, strong shock resistance ability in rough sea and stable output power. So it is regarded as a promising energy utilization facility. The research on hydrodynamic performance of wave capture buoys is the precondition and key to the wave energy device design and optimization. A simplified motion model of the buoys in the waves is established. Based on linear wave theory, the equations of motion of buoys are derived according to Newton’s second law. The factors of wave and buoys structural parameters on wave energy absorption efficiency are discussed in the China’s Bohai Sea with short wave period and small wave height. The results show that the main factor which affects the dynamic responses of wave capture buoys is the proximity of the natural frequency of buoys to the wave period. And the incoming wave power takes a backseat role to it at constant wave height. The buoys structural parameters such as length, radius and immersed depth, influence the wave energy absorption efficiency, which play significant factors in device design. The effectiveness of this model is validated by the sea tests with small-sized wave energy devices. The establishment methods of motion model and analysis results are expected to be helpful for designing and manufacturing of floating-type wave energy converter.

Open access

Wenjuan Li, Wei Liu, Xu Xu and Zhijun Gao

Abstract

Under the new normal of China’s economy, the competition among the port enterprises is not only the competition of the core competence of the port, the port industry chain or the port supply chain, but also the competition of the port service ecosystem. In this paper, the concept and characteristics of the port service ecosystem is discussed, a hierarchical model of the port service ecosystem is constructed. As an extended logistic model, Lotka-Volterra model is applied to study the competitive co-evolution and mutually beneficial co-evolution of enterprises in the port service ecosystem. This paper simulates the co-evolution of enterprises in the port service ecosystem by using MATLAB programming. The simulation results show that the breadth of the niche of the enterprises is changing with the change of the competition coefficient and the coefficient of mutual benefit in the port service ecosystem. Based on that, some proposals are put forward to ensure the healthy and orderly development of the port service ecosystem.

Open access

Guanying Wang, Xinran Li, Renli Jiang, Yue Li, Xiaojing Fan, Yu Zheng and Li Gao

Abstract

The purpose of the study was to define transient changes in the concentration of inflammatory biomarkers and cartilage biomarkers in the synovial fluid of joints following experimentally induced acute equine synovitis. Acute synovitis was induced in eight skeletally mature mares by a sterile intra-articular injection of 1 mL of phosphate-buffered saline (PBS) containing 0.5 ng of lipopolysaccharide (LPS). The solution was injected into the right middle carpal joint. One mL of sterile PBS was injected into the left control joint. Synovial fluid was obtained at the baseline level and at 8, 24, and 168 h after injection. The levels of inflammatory biomarkers-prostaglandin E2 (PGE2), interleukin 1β (IL-1β), and tumour necrosis factor-α (TNF-α), and cartilage turnover biomarkers-collagenase-cleavage neoepitope of type II collagen (C2C) and C-terminal crosslinked telopeptide type II collagen (CTX-II) were detected with proper assays. Single injections of LPS raised the number of synovial white blood cells and concentrations of total protein, PGE2, IL-1β, TNF-α, C2C, and CTX-II. PGE2 and IL-1β rose sharply at 8 h, while TNF-α increased steadily through 8 h and 24 h, at that point; these three factors returned to the baseline level by 168 h. The time course of C2C and CTX-II concentrations peaked sharply at 24 h, and continued to be significantly elevated over the baseline level even at 168 h. Injections of LPS into the joints led to a temporal inflammatory response, which in turn increased local release of inflammatory biomarkers and significantly altered the concentrations of cartilage markers in the synovial fluid.

Open access

Li Xican, Gao Yaoxiang, Han Weijuan, Lin Jing, Hu Qiuping and Chen Dongfeng

Abstract

Hylocereus undatus flower is commonly used as food or for medicinal purposes in south China. To study its antioxidant activity and mechanism we used antioxidant and chemical assays to compare two commercial samples from different locations (Shenjing, Qixing). The difference in antioxidant levels corresponded with differences in chemical content (including total phenolics, total flavonoids, kaempferol and quercetin) between Shenjing and Qixing. The antioxidant ability of H. undatus flower seems attributable to total phenolics (mainly total flavonoids). Kaempferol is one of the main bioactive components. H. undatus flower exerts its antioxidant effects through metal chelation and radical scavenging via hydrogen atom (H•) and electron (e) donation.

Open access

Yaodan Chi, Bin Li, Xiaotian Yang, Tianhao Wang, Kaiyu Yang and Yinhan Gao

Abstract

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

Open access

Li-Wei Gao and Guo-Liang Wang

Abstract

Lung cancer (LC), which includes small-cell lung carcinoma (SCLC) and non-small-cell lung carcinoma (NSCLC), is common and has a high fatality rate. This study aimed to reveal the prognostic mechanisms of LC. GSE30219 was extracted from the Gene Expression Omnibus (GEO) database, and included 293 LC samples and 14 normal lung samples. Differentially expressed genes (DEGs) were identified using the Limma package, and subjected to pathway enrichment analysis using DAVID. MicroRNAs (miRNAs) targeting the DEGs were predicted using Webgestalt. Cytoscape software was used to build a protein-protein interaction (PPI) network and to identify significant network modules. Survival analysis was conducted using Survminer and Survival packages, and validation was performed using The Cancer Genome Atlas (TCGA) dataset. The good and poor prognosis groups contained 518 DEGs. miR-190, miR-493, and miR-218 for the upregulated genes and miR-302, miR-200, and miR-26 for the downregulated genes were predicted. Three network modules (module 1, 2, and 3) were identified from the PPI network. CDK1, MCM10, and NDC80 were the core nodes of module 1, 2, and 3, respectively. In module 1, CDK1 interacted with both CCNB1 and CCNB2. Additionally, CDK1, CCNB1, CCNB2, MCM10, and NDC80 expression levels correlated with clinical survival and were identified as DEGs in both GSE30219 and the TCGA dataset. miR-190, miR-493, miR-218, miR-200, and miR-302 might act in LC by targeting the DEGs. CDK1, CCNB1, CCNB2, MCM10, and NDC80 might also influence the prognosis of LC.

Open access

Jun Cheng, Min Li, Ping Gao, Jin-ling Dong and Qi Wang

Abstract

Liver steatosis is a pathological hallmark in patients with chronic hepatitis C (CHC). Increased lipid uptake, decreased lipid secretion, increased lipid synthesis and decreased lipid degradation are all involved in pathogenesis of steatosis induced by hepatitic C virus (HCV) infection. Level of low density lipoprotein receptor (LDL-R) and activity of peroxisome proliferator-activated receptor (PPAR) α is related to liver uptake of lipid from circulation, and affected by HCV. Secretion via microsomal triglyceride transfer protein (MTTP), and formation of very low density lipoprotein (VLDL) have been hampered by HCV infection. Up-regulation of lipid synthesis related genes, such as sterol regulatory element-binding protein (SREBP)-1, SREBP-2, SREBP-1c, fatty acid synthase (FASN), HMG CoA reductase (HMGCR), liver X receptor (LXR), acetyl-CoA carboxylase 1 (ACC1), hepatic CB (1) receptors, retinoid X receptor (RXR) α, were the main stay of liver steatosis pathogenesis. Degradation of lipid in liver is decreased in patients with CHC. There is strong evidence that heterogeneity of HCV core genes of different genotypes affect their effects of liver steatosis induction. A mechanism in which steatosis is involved in HCV life cycle is emerging.

Open access

Qin Zhou, Yu-feng Gao, Xiao-miao Zhao, Fa-ming Pan and Xu Li

Abstract

Objective To investigate the relationship between single nucleotide polymorphisms (SNPs) of the interleukin-4 (IL-4) gene and outcome of hepatitis B virus (HBV) infection in a Chinese Han population.

Methods Total of 501 patients with chronic hepatitis B virus (HBV) infection and 301 controls with selflimiting HBV infection were studied. Three tag SNPs in the IL-4 gene (rs2227284G/T, rs2243283C/G and rs2243288A/G) were genotyped by the Multiplex snapshot technique. The genotype and allele frequencies were calculated and analyzed.

Results The three SNPs showed no significant genotype/allele associations with chronic HBV infection. Overall allele P values were: rs2227284, P = 0.655, odds ratio (OR) [95% confidence interval (CI)] = 1.070 (0.793-1.445); rs2243283, P = 0.849, OR (95% CI) = 0.976 (0.758-1.257); rs2243288, P = 0.659, OR (95% CI) = 1.060 (0.818-1.375). Overall genotype P values were: rs2227284, P = 0.771; rs2243283, P = 0.571; rs2243288, P = 0.902. There were no statistically significant differences between patients with chronic HBV infection and controls. Haplotypes generated by these three SNPs also had no significant differences between the two groups.

Conclusions The three tag SNPs of IL-4 were not associated with the outcome of HBV infection in the Han Chinese population.

Open access

Dadji Stéphane Serge Bonny, Xin Li, Zheng Li, Meng Li, Manting Du, Lingling Gao and Dequan Zhang

Abstract

The objective of this study was to investigate the colour stability and lipid oxidation of beef under different packaging methods. The muscles longissimus lumborum were randomly packed in vacuum or modified atmosphere packaging (MAP, 80% O2, 20% CO2). Both packages were aged at 4°C for 7, 14 and 21 days. After each ageing time, samples were displayed in a refrigerator for 2, 4 and 6 days. Colour stability, lipid oxidation and their correlation were determined. Beef under vacuum packaging showed higher a* values on 7, 14, and 21 days of ageing and lower L* values on 14 and 21 days of ageing than beef in MAP (p<0.05). Lower a* values were observed in the samples packed in MAP, then displayed compared to samples packed in vacuum, then displayed after 21 days of ageing time on day 2, 4 and 6 of the display period (p<0.05). Thiobarbituric acid reactive substances (TBARS) increased significantly in MAP compared to vacuum during 7, 14, and 21 days of ageing (p<0.05). An increase of TBARS was also observed during display after 14 and 21 days of ageing in samples packed in MAP, then displayed. Furthermore, a significant difference (p<0.05) was observed between samples packed in MAP and vacuum in peroxide value on 14 days of ageing. Lipid oxidation was observed mainly in the samples packed in MAP compared to vacuum, and positively correlated with results on colour stability.

Open access

Xinran Li, Renli Jiang, Guanying Wang, Yue Li, Xiaojing Fan, Xu Liu, Jinglu Wang, Jialiang Pan and Li Gao

Abstract

The study was conducted on 24 Mongolian horses, with oligofructose-induced equine laminitis (10 g/kg b.w.). The objective of the study was to investigate the relationships among matrix metalloproteinase 2 (MMP-2), P38 mitogen-activated protein kinases (P38 MAPK), tissue inhibitor of metalloproteinase 2 (TIMP-2), lipopolysaccharides (LPS), and tumour necrosis factor-α (TNF-α) during acute developmental phase of laminitis, and to determine whether there are any characteristic tendencies. Moreover, plasma concentrations of LPS and TNF-α were measured in order to determine the time of leukocytes’ activation. Eleven of the 12 horses showed clinical signs of laminitis. The contents of MMP-2 and P38 MAPK increased significantly from 8 h to 64 h, and the content of TIMP-2 decreased significantly at the same time. Plasma LPS concentrations increased significantly between 8 h and 20 h and reached a peak of 0.024 ± 0.009 EU/mL (equivalent to 3.04 ± 1.19 pg/mL) at 12 h. TNF-α concentration increased between 20 h and 36 h. This data indicates that MMP-2 plays an important role during the early acute developmental phase of oligofructose-induced equine laminitis.