53 results on '"Liang Dai"'
Search Results
2. Toward embedding-based multi-label feature selection with label and feature collaboration
- Author
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Liang Dai, Jia Zhang, Guodong Du, Candong Li, Rong Wei, and Shaozi Li
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Artificial Intelligence ,Software - Published
- 2022
3. Application of novel binary optimized machine learning models for monthly streamflow prediction
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Rana Muhammad Adnan, Hong-Liang Dai, Reham R. Mostafa, Abu Reza Md. Towfiqul Islam, Ozgur Kisi, Ahmed Elbeltagi, and Mohammad Zounemat-Kermani
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Water Science and Technology - Abstract
Accurate measurements of available water resources play a key role in achieving a sustainable environment of a society. Precise river flow estimation is an essential task for optimal use of hydropower generation, flood forecasting, and best utilization of water resources in river engineering. The current paper presents the development and verification of the prediction abilities of new hybrid extreme learning machine (ELM)-based models coupling with metaheuristic methods, e.g., Particle swarm optimization (PSO), Mayfly optimization algorithm (MOA), Grey wolf optimization (GWO), and simulated annealing (SA) for monthly streamflow prediction. Prediction precision of standalone ELM model was compared with two-phase optimized state-of-the-arts models, e.g., ELM–PSO, ELM–MOA, ELM–PSOGWO, and ELM–SAMOA, respectively. Hydro-meteorological data acquired from Gorai and Padma Hardinge Bridge stations at Padma River Basin, northwestern Bangladesh, were utilized as inputs in this study to employ models in the form of seven different input combinations. The model’s performances are appraised using Nash–Sutcliffe efficiency, root-mean-square-error (RMSE), mean absolute error, mean absolute percentage error and determination coefficient. The tested results of both stations reported that the ELM–SAMOA and ELM–PSOGWO models offered the best accuracy in the prediction of monthly streamflows compared to ELM–PSO, ELM–MOA, and ELM models. Based on the local data, the ELM–SAMOA reduced the RMSE of ELM, ELM–PSO, ELM–MOA, and ELM–PSOGWO by 31%, 27%, 19%, and 14% for the Gorai station and by 29%, 27%, 19%, and 14% for Padma Hardinge bridge station, in the testing stage, respectively. In contrast, based on external data, ELM–PSOGWO improves in RMSE of ELM, ELM–PSO, ELM–MOA, and ELM–SAMOA by 20%, 5.1%, 6.2%, and 4.6% in the testing stage, respectively. The results confirmed the superiority of two-phase optimized ELM–SAMOA and ELM–PSOGWO models over a single ELM model. The overall results suggest that ELM–SAMOA and ELM–PSOGWO models can be successfully applied in modeling monthly streamflow prediction with either local or external hydro-meteorological datasets.
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- 2023
4. Cyclic Lateral Responses of Monopiles Considering the Influence of Pile—Soil Relative Stiffness in Sand
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Yang Wang, Ming-xing Zhu, Wei-ming Gong, Guo-liang Dai, Jin-biao Wu, and Wen-bo Zhu
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Renewable Energy, Sustainability and the Environment ,Mechanical Engineering ,Ocean Engineering ,Oceanography - Published
- 2022
5. Study on Unloading Creep Characteristics of the Soil and Application of the Stress-Dependent Creep Model in Suction Caisson Foundation
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Wen-bo Zhu, Guo-liang Dai, Wei-ming Gong, and Xue-liang Zhao
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Renewable Energy, Sustainability and the Environment ,Mechanical Engineering ,Ocean Engineering ,Oceanography - Published
- 2022
6. Nanosensitizers for sonodynamic therapy for glioblastoma multiforme: current progress and future perspectives
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Qing-Long Guo, Xing-Liang Dai, Meng-Yuan Yin, Hong-Wei Cheng, Hai-Sheng Qian, Hua Wang, Dao-Ming Zhu, and Xian-Wen Wang
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Brain Neoplasms ,Ultrasonic Therapy ,Humans ,General Medicine ,Glioblastoma ,Ultrasonography - Abstract
Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor, and it is associated with poor prognosis. Its characteristics of being highly invasive and undergoing heterogeneous genetic mutation, as well as the presence of the blood–brain barrier (BBB), have reduced the efficacy of GBM treatment. The emergence of a novel therapeutic method, namely, sonodynamic therapy (SDT), provides a promising strategy for eradicating tumors via activated sonosensitizers coupled with low-intensity ultrasound. SDT can provide tumor killing effects for deep-seated tumors, such as brain tumors. However, conventional sonosensitizers cannot effectively reach the tumor region and kill additional tumor cells, especially brain tumor cells. Efforts should be made to develop a method to help therapeutic agents pass through the BBB and accumulate in brain tumors. With the development of novel multifunctional nanosensitizers and newly emerging combination strategies, the killing ability and selectivity of SDT have greatly improved and are accompanied with fewer side effects. In this review, we systematically summarize the findings of previous studies on SDT for GBM, with a focus on recent developments and promising directions for future research.
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- 2022
7. Experimental Investigation of the Performance of a 3D Printed Heat Pipe with Ultra-Small Bending Radius for Space Applications
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Kai-Xuan Zhao, Yang Duan, Shan-Liang Dai, Le Pang, Min-Jie Wang, Jian-Feng Tong, Jing-Wen Sun, and Sheng-Li Zhu
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Applied Mathematics ,Modeling and Simulation ,General Engineering ,General Physics and Astronomy - Published
- 2022
8. The offline data quality monitoring of the BESIII end-cap TOF system
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Ming-Ming Ma, Jing-Yi Liu, Shuo-Pin Wen, Sheng-Sen Sun, Chun-Xiu Liu, Yong-Zhao Sun, Zi-Yan Deng, Ye Yuan, Hong-Liang Dai, Zhi Wu, Yue-Kun Heng, and Huai-Min Liu
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Nuclear and High Energy Physics ,Nuclear Energy and Engineering - Published
- 2021
9. CDC20 and PTTG1 are Important Biomarkers and Potential Therapeutic Targets for Metastatic Prostate Cancer
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Liang Dai, Yin-Lu Dang, Zhao Yuming, Zi-Xuan Song, Zhang Limin, Ji-Dong Zhang, Liang Zhao, Bai-Bing Wang, Li-Ying Li, Jun-Qiang Liang, Wang-Teng Ma, and Da-Peng Wei
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Male ,030213 general clinical medicine ,Lung Neoplasms ,Cell division ,Cdc20 Proteins ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,medicine ,Humans ,Pharmacology (medical) ,Survival analysis ,Migration Assay ,Cell growth ,business.industry ,Gene Expression Profiling ,Computational Biology ,Prostatic Neoplasms ,Cancer ,General Medicine ,Cell cycle ,medicine.disease ,Gene Expression Regulation, Neoplastic ,Securin ,Gene Ontology ,030220 oncology & carcinogenesis ,Cancer research ,Immunohistochemistry ,business ,Biomarkers - Abstract
Metastatic prostate cancer (mPCa) is responsible for most prostate cancer (PCa) deaths worldwide. The present study aims to explore the molecular differences between mPCa and PCa. The authors downloaded GSE6752, GSE6919, and GSE32269 from the Gene Expression Omnibus and employed integrated analysis to identify differentially expressed genes (DEGs) between mPCa and PCa. Functional and pathway-enrichment analyses were performed, and a protein–protein interaction (PPI) network and modules were constructed. Clinical mPCa specimens were collected to verify the results by performing RT-qPCR. The Cancer Genome Atlas database was used to conduct a survival analysis, and an immunohistochemical assay was performed. The invasion ability of PCa cells was verified by Transwell assay. One-hundred six consistently DEGs were found in mPCa compared with PCa. DEGs significantly enriched the positive regulation of cell proliferation, cell division, and cell adhesion in small cell lung cancer and PCa. Cell division, nucleoplasm, and cell cycle were selected from the PPI network, and the top 10 hub genes were selected. CDC20 and PTTG1 with genetic alterations were significantly associated with poorer disease-free survival. Immunohistochemical assay results showed that the expression levels of CDC20 and PTTG1 in mPCa were higher than those in PCa. The results of the migration assay indicated that CDC20 and PTTG1 could enhance the migration ability of PCa cells. The present study revealed that CDC20 and PTTG1 contribute more to migration, progression, and poorer prognoses in mPCa compared with PCa. CDC20 and PTTG1 could represent therapeutic targets in mPCa medical research and clinical studies.
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- 2021
10. Dexmedetomidine alleviates pulmonary edema through the epithelial sodium channel (ENaC) via the PI3K/Akt/Nedd4-2 pathway in LPS-induced acute lung injury
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Xue-Ping Zhang, Zhong-Liang Dai, Jing Xu, Qiang Huang, Mingzhu Xia, and Yuan-Xu Jiang
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Lipopolysaccharides ,Male ,0301 basic medicine ,Epithelial sodium channel ,Cell Survival ,Nedd4 Ubiquitin Protein Ligases ,Acute Lung Injury ,ENaC ,Immunology ,Lung injury ,Pharmacology ,Phosphatidylinositol 3-Kinases ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Pulmonary edema ,Adrenergic alpha-2 Receptor Agonists ,medicine ,Animals ,Edema ,Humans ,Rats, Wistar ,Epithelial Sodium Channels ,Lung ,Protein kinase B ,PI3K/AKT/mTOR pathway ,A549 cell ,medicine.diagnostic_test ,Chemistry ,respiratory system ,medicine.disease ,AFC ,030104 developmental biology ,Bronchoalveolar lavage ,A549 Cells ,030220 oncology & carcinogenesis ,Cytokines ,Original Article ,PI3K/Akt/Nedd4-2 signaling pathway ,Proto-Oncogene Proteins c-akt ,Dexmedetomidine ,hormones, hormone substitutes, and hormone antagonists ,Signal Transduction - Abstract
Dexmedetomidine (Dex), a highly selective α2-adrenergic receptor (α2AR) agonist, has an anti-inflammatory property and can alleviate pulmonary edema in lipopolysaccharide (LPS)-induced acute lung injury (ALI), but the mechanism is still unclear. In this study, we attempted to investigate the effect of Dex on alveolar epithelial sodium channel (ENaC) in the modulation of alveolar fluid clearance (AFC) and the underlying mechanism. Lipopolysaccharide (LPS) was used to induce acute lung injury (ALI) in rats and alveolar epithelial cell injury in A549 cells. In vivo, Dex markedly reduced pulmonary edema induced by LPS through promoting AFC, prevented LPS-induced downregulation of α-, β-, and γ-ENaC expression, attenuated inflammatory cell infiltration in lung tissue, reduced the concentrations of TNF-α, IL-1β, and IL-6, and increased concentrations of IL-10 in bronchoalveolar lavage fluid (BALF). In A549 cells stimulated with LPS, Dex attenuated LPS-mediated cell injury and the downregulation of α-, β-, and γ-ENaC expression. However, all of these effects were blocked by the PI3K inhibitor LY294002, suggesting that the protective role of Dex is PI3K-dependent. Additionally, Dex increased the expression of phosphorylated Akt and reduced the expression of Nedd4-2, while LY294002 reversed the effect of Dex in vivo and in vitro. Furthermore, insulin-like growth factor (IGF)-1, a PI3K agonists, promoted the expression of phosphorylated Akt and reduced the expression of Nedd4-2 in LPS-stimulated A549 cells, indicating that Dex worked through PI3K, and Akt and Nedd4-2 are downstream of PI3K. In conclusion, Dex alleviates pulmonary edema by suppressing inflammatory response in LPS-induced ALI, and the mechanism is partly related to the upregulation of ENaC expression via the PI3K/Akt/Nedd4-2 signaling pathway.
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- 2021
11. Adsorption of Pb2+ by insolubilized humic acid extracted from sewage sludge
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Kang Zhang, Liang Dai, Weifan Zhao, Bigui Wei, and Tao Han
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chemistry.chemical_classification ,Diffusion ,0211 other engineering and technologies ,Langmuir adsorption model ,Alcohol ,02 engineering and technology ,010501 environmental sciences ,Raw material ,01 natural sciences ,symbols.namesake ,chemistry.chemical_compound ,Adsorption ,chemistry ,Mechanics of Materials ,symbols ,Humic acid ,Sewage treatment ,021108 energy ,Waste Management and Disposal ,Sludge ,0105 earth and related environmental sciences ,Nuclear chemistry - Abstract
This study used excess sludge from a sewage treatment plant as raw material to extract humic acid (HA) and explore the ability of HA to adsorb Pb2+ from a solution. The effects of the adsorbent amount, solution pH, and co-existing cations on the adsorption process were investigated. The study showed that the humic acid derived from sludge (S-HA) surface had a loose, clustered texture. The S-HA surface contained many oxygen-containing functional groups, such as carboxyl groups, alcohol hydroxyl groups, and phenolic hydroxyl groups. The presence of co-existing cations, such as Na+, NH4+ and Ca2+, in the solution was not conducive to the adsorption of Pb2+ by S-HA. As the solution pH increased, the adsorption of Pb2+ by S-HA gradually increased. The process by which S-HA adsorbed Pb2+ conformed to a pseudo-second order kinetic model. Additionally, the overall adsorption rate was controlled by liquid membrane diffusion and intra-particle diffusion. The adsorption isotherm followed the Langmuir model, and the S-HA had a maximum adsorption capacity of 27.59 mg/g at 25 °C. The adsorption dynamics and thermodynamics results showed that the adsorption of Pb2+ by S-HA occurred via both physical adsorption and chemical adsorption processes.
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- 2021
12. Shortened key growth periods of soybean observed in China under climate change
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Yujie Liu, Qinghua Tan, Liang Dai, and Tao Pan
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Crops, Agricultural ,China ,010504 meteorology & atmospheric sciences ,Vegetative reproduction ,Climate Change ,Science ,Growing season ,Climate change ,Biology ,01 natural sciences ,Article ,Spatio-Temporal Analysis ,Anthesis ,0105 earth and related environmental sciences ,Multidisciplinary ,Phenology ,Global warming ,Temperature ,food and beverages ,Sowing ,04 agricultural and veterinary sciences ,Agronomy ,Sunshine duration ,040103 agronomy & agriculture ,Medicine ,0401 agriculture, forestry, and fisheries ,Soybeans ,Climate-change impacts - Abstract
Phenology is an important indicator of global climate change. Revealing the spatiotemporal characteristics of crop phenology is vital for ameliorating the adverse effects of climate change and guiding regional agricultural production. This study evaluated the spatiotemporal variability of soybean’s phenological stages and key growth periods, and assessed their sensitivity to key climatic factors, utilizing a long-term dataset (1992–2018) of soybean phenology and associated meteorological data collected at 51 stations across China. The results showed that (1) during the soybean growing seasons from 1992 to 2018, the average temperature (0.34 ± 0.09 ℃ decade−1) and cumulative precipitation (6.66 ± 0.93 mm decade−1) increased, but cumulative sunshine hours (− 33.98 ± 1.05 h decade−1) decreased. (2) On a national scale, dates of sowing, emergence, trifoliate, anthesis, and podding of soybean were delayed, while the maturity date showed an advancing trend. The vegetative growth period (− 0.52 ± 0.24 days decade−1) and whole growth period (− 1.32 ± 0.30 days decade−1) of soybean were shortened, but the reproductive growth period (0.05 ± 0.26 days decade−1) was slightly extended. Trends in soybean phenological stages and key growth periods diverged in regions. Soybean phenological stages were delayed in Huang-Huai-Hai soybean zone, whereas advanced in southern soybean zone. Moreover, the key growth periods were greatly shortened in northern soybean zone. (3) In general, the sensitivity of soybean key growth periods to temperature was negative, whereas those to precipitation and sunshine hours differed among regions. In particular, most phenological stages were negatively sensitive to sunshine hours. Our results will provide scientific support for decision-making in agricultural production practices.
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- 2021
13. C677T polymorphism increases the risk of early spontaneous abortion
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Fan Zhang, Liang Dai, and Yongjie Liu
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Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Genotype ,MTHFR C677T polymorphism ,Reproductive medicine ,Abortion ,Polymorphism, Single Nucleotide ,Early spontaneous abortion ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Pregnancy ,Risk Factors ,Genetics ,medicine ,Humans ,Male population ,Mthfr c677t ,Genetic Predisposition to Disease ,Methylenetetrahydrofolate Reductase (NADPH2) ,reproductive and urinary physiology ,Genetics (clinical) ,030219 obstetrics & reproductive medicine ,biology ,Obstetrics ,business.industry ,Obstetrics and Gynecology ,General Medicine ,digestive system diseases ,Human genetics ,Abortion, Spontaneous ,030104 developmental biology ,Reproductive Medicine ,Case-Control Studies ,Methylenetetrahydrofolate reductase ,biology.protein ,Female ,business ,Developmental Biology - Abstract
Purpose To investigate the relationship of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in male population having spouses with early spontaneous abortion. Methods A total of 345 males whose spouses had at least one early spontaneous abortion were included in the study group, and 145 males who planned to have a second child were included in the control group. Semen was collected in a sterile cup by masturbation. After liquefaction, the sperm concentration and forward motility sperm rate (PR) were obtained. The genomic DNA was extracted from peripheral vein, followed by MTHFR C677T polymorphism detection through PCR-gold magnetic nanoparticle chromatography. Results The numbers of alleles and genotypes of MTHFR in the case group were 303 (C), 387 (T), 64 (CC), 175 (CT), and 106 (TT) cases, respectively. The numbers of allele and genotype of MTHFR in the control group were 167 (C), 123 (T), 145 (CC), 65 (CT), and 29 (TT) cases. There were significant differences in the distribution frequency of genotypes (χ2 = 17.005, P = 0.000) and alleles (χ2 = 15.295, P = 0.000) between the two groups. For cases with more spontaneous abortion, more cases had CT and TT phenotypes. Participants with genotype CT had the highest sperm concentration and PR in both groups (P
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- 2019
14. Effect of magnetic seeding agglomeration on flotation of fine minerals
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Liang Dai, Xi-qing Wu, and Tao Yue
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Flocculation ,Materials science ,Magnetism ,Polyacrylamide ,0211 other engineering and technologies ,02 engineering and technology ,engineering.material ,chemistry.chemical_compound ,Adsorption ,stomatognathic system ,020401 chemical engineering ,Coal ,0204 chemical engineering ,021102 mining & metallurgy ,business.industry ,Economies of agglomeration ,Metals and Alloys ,General Engineering ,food and beverages ,Hematite ,equipment and supplies ,chemistry ,Chemical engineering ,visual_art ,visual_art.visual_art_medium ,engineering ,Pyrite ,business ,human activities - Abstract
Magnetic seeding agglomeration (MSA), i.e., adding magnetic seeds and a low intensity pre-magnetization for fine agglomeration, was applied to the flotation of coal, pyrite and hematite ore slimes. Size analysis and flotation tests highlight that the MSA improved flotation recovery and kinetics of pyrite ore while causing some loss in selectivity, and in the presences of the polyacrylamide for coal and starch for hematite the agglomeration flotation was further strengthened due to the synergetic effect between the flocculants and magnetic seeds. Magnetism analyses and calculation confirmed the adsorption of magnetic seeds onto minerals, resulting in a decreased threshold magnetic field intensity for the MSA to happen. Then atomic force microscope (AFM) study found that there exists a long range force between magnetic seeds and minerals, which facilitates the adsorption of magnetic seeds on minerals. FTIR shows both the polyacrylamide and starch adsorbed onto minerals and magnetic seeds, thus acting as the bridging media between minerals and magnetic seeds, intensifying the agglomeration in flotation. Surface characterization of the MSA was understood by SEM imaging, and models of the MSA were proposed.
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- 2019
15. Microstructure and mechanical properties of friction stir welding joint during post weld heat treatment with different zigzag lines
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Zhi-Li Hu, Qiu Pang, and Ming-Liang Dai
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Materials science ,Metals and Alloys ,Welding ,Condensed Matter Physics ,Microstructure ,Indentation hardness ,law.invention ,Zigzag ,law ,Residual stress ,Ultimate tensile strength ,Materials Chemistry ,Friction stir welding ,Physical and Theoretical Chemistry ,Composite material ,Joint (geology) - Abstract
Zigzag line is a common defect in friction stir welding (FSW) joint. The formation mechanism of the zigzag line in Al–Cu alloy FSW joint and its influence on the microstructure and mechanical properties during post weld heat treatment (PWHT) were studied by scanning electron microscopy (SEM), microhardness and tensile tests. It is found that the occurrence of zigzag line for PWHT joint is determined by PWHT process which in nature depends on residual stress and thermal stress of FSW joint. The optimization of PWHT process to reduce the residual and thermal stress can trigger for the deterioration of mechanical properties of PWHT joints with zigzag line. No obvious decrease of tensile properties is observed for T6-450 and T6-495 joints although zigzag line appears in the weld. PWHT determines the sizes of zigzag line cracks and consequently determines the fracture location and characteristics of FSW joint.
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- 2018
16. Correction to: The offline data quality monitoring of the BESIII end-cap TOF system
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Ming-Ming Ma, Jing-Yi Liu, Shuo-Pin Wen, Sheng-Sen Sun, Chun-Xiu Liu, Yong-Zhao Sun, Zi-Yan Deng, Ye Yuan, Hong-Liang Dai, Zhi Wu, Yue-Kun Heng, and Huai-Min Liu
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Nuclear and High Energy Physics ,Nuclear Energy and Engineering - Published
- 2021
17. Development and Cross-Cultural Validity of a Brief Measure of Separation-Individuation
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Danica G. Hays, Mark H. C. Lai, Ching-Chen Chen, Chia-Liang Dai, and George B. Richardson
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05 social sciences ,050109 social psychology ,Health outcomes ,Confirmatory factor analysis ,Developmental psychology ,050106 general psychology & cognitive sciences ,Convergent validity ,Item response theory ,Developmental and Educational Psychology ,Separation individuation ,Cross-cultural ,0501 psychology and cognitive sciences ,Measurement invariance ,Adolescent development ,Life-span and Life-course Studies ,Psychology - Abstract
Separation from parents is a key aspect of adolescent development and has been linked to a variety of important mental and behavioral health outcomes. Separation-individuation measures were developed in the United States and have been used in Asian contexts. However, no cross-cultural studies have demonstrated that measures of separation-individuation tap the same domains across Asian and American adolescents. This article describes two studies conducted to develop and initially validate a scale for measuring adolescent separation-individuation. Study 1 (n = 300) developed a Brief Measure of Separation-Individuation (BMSI) using Confirmatory Factor Analysis and Item Response Theory. The result was a 32-item BMSI that provided comparable test information to the original 148-item measure. Study 2 examined the BMSI for measurement invariance and convergent validity across U.S. and Taiwanese samples (ns = 231 and 323). Findings suggest that functional independence, attitudinal independence, and emotional independence may be culturally invariant separation-individuation constructs. However, conflictual independence seems to be more culturally dependent in that its items were only partially scalar invariant and it was only loosely related to the other separation-individuation factors. Findings are consistent with previous research that recommended against using total scores for the PSI (i.e., scoring a single separation-individuation dimension). This study suggests the BMSI holds promise as a brief measure of separation-individuation that can be used in cross-cultural research.
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- 2018
18. Changing Connectivities of Chinese Cities in the World City Network, 2010–2016
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Liang Dai, Wei Shen, Freke Caset, Peter J. Taylor, Zhan Cao, Frank Witlox, Xingjian Liu, Weiyang Zhang, and Ben Derudder
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Data collection ,05 social sciences ,Geography, Planning and Development ,0211 other engineering and technologies ,0507 social and economic geography ,021107 urban & regional planning ,02 engineering and technology ,Network formation ,Globalization ,Politics ,Beijing ,Order (exchange) ,General Earth and Planetary Sciences ,Position (finance) ,Business ,Economic geography ,China ,050703 geography - Abstract
Against the backdrop of the sizable economic growth of China in recent years, this paper uses the most recent data gathering of the Globalization and World Cities (GaWC) research network to update and supplement earlier research on the shifting global connectivity of Chinese cities. The update consists of an evaluation of the connectivity of Chinese cities in 2016, the supplement of an analysis of the changing position of Chinese cities in the world city network between 2010 and 2016. To this end, we build on a specification of the world city network as an ‘interlocking network’ in which producer services firms play the crucial role in city network formation. Information about the presence of leading producer services firms in cities in 2010 and 2016 is used as the input to a bipartite network projection algorithm in order to measure cities’ network connectivity. The first set of results discusses the geographies of urban connectivity in the world city network in 2016. The second set of results discusses standardized measures of change to reveal the major dimensions of the transformations between 2010 and 2016. We find that, with the exception of Hong Kong, Macau and Kaohsiung of Taiwan, all Chinese cities record connectivity gains. This wholesale rise in connectivity is nonetheless geographically uneven, with above all Beijing, Chengdu/Chongqing and Changsha/Wuhan becoming more connected. We conclude that the wholesale rise of Chinese cities in the world city network and their changing trajectories in the post-crisis era are embedded in shifting external and internal political economies.
- Published
- 2018
19. A Call for, and Beginner’s Guide to, Measurement Invariance Testing in Evolutionary Psychology
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George B. Richardson, Chia-Liang Dai, Ching-Chen Chen, and Shanshan Wang
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Social Psychology ,Syntax (programming languages) ,05 social sciences ,Inference ,050109 social psychology ,Popularity ,Evolutionary psychology ,050105 experimental psychology ,Test (assessment) ,Item response theory ,0501 psychology and cognitive sciences ,Measurement invariance ,Construct (philosophy) ,Psychology ,Social psychology ,Cognitive psychology - Abstract
Measurement invariance is a statistical property of an instrument (e.g., a test or questionnaire) indicating that it measures the same construct(s) in the same way across subgroups of respondents. Given the extensive research in evolutionary psychology devoted to sex differences and cross-cultural comparisons, measurement invariance testing is crucial not only because it protects against erroneous inference, but also because it provides nuanced information about group similarities and differences. In this article, we draw attention to the importance of, and present a beginner’s guide to, measurement invariance testing. We define measurement invariance formally, summarize sources of non-invariance and the rationale for measurement invariance testing, and describe the two frameworks typically used to test for invariance. We then review evidence of a relative lack of measurement invariance testing in evolutionary psychology and conclude with a case example with MPlus syntax. By testing for measurement invariance, researchers studying evolutionary psychology can strengthen their field and enhance the popularity of their constructs in other disciplines.
- Published
- 2017
20. Linkages among fiber content, porosity and local aggregation in fiber-reinforced composites, and their effect on effective properties
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Yang Yang, Yan-Ni Rao, Hong-Liang Dai, and Ting Dai
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Materials science ,Economies of agglomeration ,Mechanical Engineering ,Stiffness ,02 engineering and technology ,Fiber-reinforced composite ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Homogenization (chemistry) ,0104 chemical sciences ,Mechanics of Materials ,Solid mechanics ,medicine ,General Materials Science ,Composite material ,medicine.symptom ,0210 nano-technology ,Porosity ,Mass fraction - Abstract
Adequate micro-modeling for composites is the basic and key precondition for their property prediction. This study takes fiber-reinforced composites (FRCs) as an example and focuses on the linkages among fiber content, porosity and aggregation in the microstructure of composites, as well as their effect on the overall mechanical properties. A novel two-parameter agglomeration model is developed to take both the tightly packed filler assemblies and the porosity into account, in which the fiber weight fraction is used as an independent variable to express the volumetric composition. Meanwhile, an improved two-scale approach based on Mori–Tanaka (M–T) homogenization theory is utilized to predict the effective properties of FRCs. Three typical FRCs: three-dimensional (3D) randomly distributed FRCs, two-dimensional (2D) randomly distributed ones and unidirectionally (UD) distributed ones, are investigated in detail. The proposed model and method are validated by available experimental data. A parametric study reveals that due to the synergistic influence of fiber content, porosity and local aggregation, a maximum stiffness of FRCs can be achieved by making fibers uniformly dispersed in the matrix and setting the fiber weight fraction to be a certain transition value, which is characterized as a best possible condition with high fiber content and low porosity.
- Published
- 2017
21. Multimessenger parameter estimation of GW170817
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David Radice and Liang Dai
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Nuclear and High Energy Physics ,Nuclear Theory ,Gravitational wave ,FOS: Physical sciences ,Binary number ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Mass ratio ,Upper and lower bounds ,Computational physics ,Nuclear Theory (nucl-th) ,Numerical relativity ,Neutron star ,Computer Science::Multimedia ,Binary star ,Invariant mass ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics::Galaxy Astrophysics - Abstract
We combine gravitational wave (GW) and electromagnetic (EM) data to perform a Bayesian parameter estimation of the binary neutron star (NS) merger GW170817. The EM likelihood is constructed from a fit to a large number of numerical relativity simulations which we combine with a lower bound on the mass of the remnant's accretion disk inferred from the modeling of the EM light curve. In comparison with previous works, our analysis yields a more precise determination of the tidal deformability of the binary, for which the EM data provide a lower bound, and of the mass ratio of the binary, with the EM data favoring a smaller mass asymmetry. The 90\% credible interval for the areal radius of a $1.4\ M_\odot$ NS is found to be $12.2^{+1.0}_{-0.8} \pm 0.2\ {\rm km}$ (statistical and systematic uncertainties)., 7 pages, 3 figures, accepted to the EPJA Topical Issue: The first Neutron Star Merger Observation - Implications for Nuclear Physics
- Published
- 2019
22. Evidence-based Chinese medicine clinical practice guideline for stomach pain in Hong Kong
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Nannan Shi, Aiping Lu, Tat Chi Ziea, Zhaoxiang Bian, Xu-Dong Tang, Liang Dai, Linda L. D. Zhong, and Bacon F.L. Ng
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medicine.medical_specialty ,Evidence-based practice ,Acupuncture Therapy ,Alternative medicine ,Pain ,Chronic gastritis ,Traditional Chinese medicine ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Pharmacology (medical) ,Medicine, Chinese Traditional ,Evidence-Based Medicine ,Traditional medicine ,business.industry ,Stomach ,General Medicine ,Guideline ,Evidence-based medicine ,medicine.disease ,030205 complementary & alternative medicine ,medicine.anatomical_structure ,Complementary and alternative medicine ,Stomach Pain ,030220 oncology & carcinogenesis ,Practice Guidelines as Topic ,Physical therapy ,Hong Kong ,business ,Drugs, Chinese Herbal - Abstract
Stomach pain in Chinese medicine (CM) is a very common disorder in clinical practice and it has been listed as one of the pilot three conditions in Hong Kong to develop evidence-based CM clinical practice guidelines (CM CPGs). The aim of this stomach Pain CPG is to summarize the treatment methods of stomach pain with CM and evaluate reasonably, then to guide local licensed CM practitioners and provide beneficial reference for social medical decision makers and patients. In this manuscript, we defined stomach pain in CM and the category of chronic gastritis in Western medicine. The clinical manifestation, CM pattern classification, and CM intervention including herbal medicine treatment based on pattern differentiation, symptomatic treatment, acupuncture treatment, regulation and nursing were illustrated.
- Published
- 2016
23. Dexmedetomidine alleviates pulmonary edema by upregulating AQP1 and AQP5 expression in rats with acute lung injury induced by lipopolysaccharide
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Xue-Ping Zhang, Qiang Huang, Wei Zhao, Zhong-Liang Dai, Yuan-Xu Jiang, and Li-Kun Gao
- Subjects
Lipopolysaccharides ,Male ,medicine.medical_specialty ,Transcription, Genetic ,Lipopolysaccharide ,medicine.medical_treatment ,Acute Lung Injury ,Interleukin-1beta ,Biomedical Engineering ,Pulmonary Edema ,Lung injury ,Biochemistry ,Drug Administration Schedule ,Biomaterials ,chemistry.chemical_compound ,Internal medicine ,Adrenergic alpha-2 Receptor Agonists ,Genetics ,medicine ,Animals ,Rats, Wistar ,Dexmedetomidine ,Lung ,Saline ,Earth-Surface Processes ,Aquaporin 1 ,Dose-Response Relationship, Drug ,Tumor Necrosis Factor-alpha ,business.industry ,Organ Size ,Pulmonary edema ,medicine.disease ,Aquaporin 5 ,Rats ,Endocrinology ,medicine.anatomical_structure ,Gene Expression Regulation ,chemistry ,Anesthesia ,Injections, Intravenous ,Immunohistochemistry ,Tumor necrosis factor alpha ,business ,Signal Transduction ,medicine.drug - Abstract
This study aims to elucidate the mechanisms by which dexmedetomidine alleviates pulmonary edema in rats with acute lung injury induced by lipopolysaccharide (LPS). Male Wistar rats were randomly divided into five groups: normal saline control (NS) group, receiving intravenous 0.9% normal saline (5 mL/kg); LPS group, receiving intravenous LPS (10 mg/kg); small-dose dexmedetomidine (S) group, treated with a small dose of dexmedetomidine (0.5 μg · kg(-1) · h(-1)); medium-dose dexmedetomidine (M) group, treated with a medium dose of dexmedetomidine (2.5 μg · kg(-1) · h(-1)); high-dose dexmedetomidine (H) group, treated with a high dose of dexmedetomidine (5 μg · kg(-1) · h(-1)). The rats were sacrificed 6 h after intravenous injection of LPS or NS, and the lungs were removed for evaluating histological characteristics and determining the lung wet/dry weight ratio (W/D). The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) in the lung tissues were assessed by enzyme- linked immunosorbent assay (ELISA). The mRNA and protein expression levels of aquaporin-1 (AQP1) and aquaporin-5 (AQP5) were detected by RT-PCR, immunohistochemistry, and Western blotting. The lung tissues from the LPS groups were significantly damaged, which were less pronounced in the H group but not in the small-dose dexmedetomidine group or medium-dose dexmedetomidine group. The W/D and the concentrations of TNF-α and IL-1β in the pulmonary tissues were increased in the LPS group as compared with those in NS group, which were reduced in the H group but not in S group or M group (P
- Published
- 2015
24. Investigation of mechanical behavior for a rotating FGM circular disk with a variable angular speed
- Author
-
Hong-Liang Dai and Ting Dai
- Subjects
Mechanical Engineering ,Equations of motion ,Angular velocity ,Geometry ,Mechanics ,Geometric shape ,Functionally graded material ,Displacement (vector) ,Mathematics::Numerical Analysis ,Shooting method ,Mechanics of Materials ,Ordinary differential equation ,Boundary value problem ,Mathematics - Abstract
In this paper, the displacement and stress distribution in a rotating FGM (Functionally graded material) circular disk with a variable angular speed are studied. The modulus of elasticity and mass density of the circular disk are assumed to vary along its radius and relate to the volume fraction of the materials, while the Poisson’s ratio remains to be a constant. The motion equations of the FGM rotating circular disk are simplified into boundary value problems of ordinary differential equation, which are solved by Runge-Kutta method, and the whole problem is solved by utilizing shooting method. Numerical results show that the functionally graded index, angular speeds and geometric shape all have significant effect on the mechanical behaviors of the rotating FGM circular disk. The results of this study may be useful for other investigations of a rotating FGM circular disk.
- Published
- 2015
25. A Novel Method for Producing Light GMT Sheets by a Pneumatic Technique
- Author
-
Y.-N. Rao and Hong-Liang Dai
- Subjects
chemistry.chemical_classification ,Thermoplastic ,Materials science ,Polymers and Plastics ,General Mathematics ,Glass fiber ,Condensed Matter Physics ,Biomaterials ,chemistry ,Flexural strength ,Mechanics of Materials ,Solid mechanics ,Ultimate tensile strength ,Ceramics and Composites ,Fiber ,Composite material - Abstract
A novel method for producing a kind of light glass-mat- reinforced thermoplastic (GMT) sheets by using a pneumatic technique is presented. The tensile and flexural properties of produced light GMT sheets, with various lengths of glass fibers and PP content, were determined experimentally. Results of the experimental investigation show that the light GMT sheets are fully suitable for engineering applications.
- Published
- 2015
26. The expression of TTF-1 and Napsin A in early-stage lung adenocarcinoma correlates with the results of surgical treatment
- Author
-
Yunfan Ma, Zhen Liang, Yu Sun, Hongchao Xiong, Xiaozheng Kang, Ke-Neng Chen, Yiqiang Liu, Wanpu Yan, Liang Dai, and Mengying Fan
- Subjects
Adult ,Male ,Oncology ,endocrine system ,medicine.medical_specialty ,Pathology ,Lung Neoplasms ,Adenocarcinoma ,Immunoenzyme Techniques ,Carcinoma, Non-Small-Cell Lung ,Internal medicine ,Biomarkers, Tumor ,Aspartic Acid Endopeptidases ,Humans ,Medicine ,Prospective Studies ,Stage (cooking) ,Surgical treatment ,Lung cancer ,Aged ,Neoplasm Staging ,Retrospective Studies ,Aged, 80 and over ,Lung ,Tissue microarray ,business.industry ,General Medicine ,Middle Aged ,respiratory system ,Prognosis ,medicine.disease ,DNA-Binding Proteins ,Survival Rate ,body regions ,medicine.anatomical_structure ,Tissue Array Analysis ,Immunohistochemistry ,Female ,Differential diagnosis ,business ,Follow-Up Studies ,Transcription Factors - Abstract
Non-small cell lung cancer (NSCLC) accounts for 80 % of lung cancers, and lung adenocarcinoma (ADC) is one of the main types of NSCLC. Although there are several studies on the relationship between lung ADC immunohistochemical diagnostic markers (thyroid transcription factor 1 (TTF-1) and Napsin A) and survival, some aspects of those studies could be improved. We examined the significance of the commonly used lung ADC diagnostic markers, including TTF-1, Napsin A, and CK7, in the prognosis of early-stage lung ADC. One hundred and nineteen cases of early-stage lung ADC (N0) were selected from the prospective database of lung cancer (Jan 2000 to Dec 2009). The expression levels of TTF-1, Napsin A, and CK7 in inventoried specimens were analyzed using tissue microarray (TMA) and immunohistochemical (IHC) analysis, and the effect of the expression level of each marker on patients’ survival was examined. The diagnostic sensitivity and specificity of each marker for lung ADC were as follows: TTF-1, 87.0 and 90.1 %; Napsin A, 72.2 and 90.4 %; and CK7, 94.6 and 76.0 %, respectively. Patients with high expression levels of TTF-1 and Napsin A, and high co-expression levels of TTF-1/Napsin A had better survival rates than those with low levels of expression (P
- Published
- 2015
27. A novel model to predict U-bending springback and time-dependent springback for a HSLA steel plate
- Author
-
Hong-Liang Dai and Hao-Jie Jiang
- Subjects
Friction coefficient ,Engineering ,business.industry ,Mechanical Engineering ,Alloy ,Bend radius ,Structural engineering ,Plasticity ,engineering.material ,Blank ,Industrial and Manufacturing Engineering ,Computer Science Applications ,Stress level ,Control and Systems Engineering ,Hardening (metallurgy) ,Kinematic hardening ,business ,Software - Abstract
In this paper, a novel model which considers initial strain related to the material’s yielding stress, the combination of stretch and bending strain and isotropic hardening rule is introduced to predict U-bending springback and time-dependent springback behaviors for a high strength and low alloy (HSLA) steel plate. It is noteworthy that time-dependent springback is associated with plastic strain hardening for the HSLA steel plate. The results obtained from the performed analysis show that the hardening exponent, bending radius and thickness ratio, friction coefficient, and blank holder force have great influences on the springback angle and stress level. Based on this novel model, the prediction of HSLA steel plate’s springback is done in the stage of tool design and hence, the accuracy of drawn part is increased.
- Published
- 2015
28. Thermoviscoelastic dynamic response for a composite material thin narrow strip
- Author
-
Hong-Liang Dai, Li-Li Qi, and Hai-Bo Liu
- Subjects
Physics::Fluid Dynamics ,Work (thermodynamics) ,Nonlinear system ,Materials science ,Series (mathematics) ,Mechanics of Materials ,Mechanical Engineering ,Thermal ,Plate theory ,Newmark-beta method ,Time domain ,Composite material ,Viscoelasticity - Abstract
Based on von Karman nonlinear strain-displacement relationships and classical thin plate theory, a list of nonlinear dynamic equilibrium equations for a viscoelastic composite material thin narrow strip under thermal and mechanic loads are deduced. According to the material constitutive relationship and the relaxation modulus in the form of the Prony series, combing with the Newmark method and the Newton-cotes integration method, a new numerical algorithm for direct solving the whole problem in the time domain is established. By applying this numerical algorithm, the viscoelastic composite material thin narrow strip as the research subject is analyzed systematically, and its rich dynamical behaviors are revealed comprehensively. To verify the accuracy of the present work, a comparison is made with previously published results. Finally, the viscoelastic composite material thin narrow strip under harmonic excitation load and impact load are discussed in detail, and many valuable thermoviscoelastic dynamic characteristics are revealed.
- Published
- 2015
29. Dynamic response analysis of a HSLA steel circular plate subjected to mechanical load in thermal environments
- Author
-
Ting Dai, Hong-Liang Dai, and Xiang Yan
- Subjects
Materials science ,Mechanical load ,Physics::Instrumentation and Detectors ,Iterative method ,business.industry ,Mechanical Engineering ,Response analysis ,Finite difference method ,Structural engineering ,Föppl–von Kármán equations ,Physics::Fluid Dynamics ,Nonlinear system ,Mechanics of Materials ,Solid mechanics ,General Materials Science ,Newmark-beta method ,business - Abstract
Dynamic response analysis of a high strength low alloy (HSLA) steel circular plate subjected to mechanical load in thermal environments is investigated. Based on the von Karman equation and classical theory of thin plate, the nonlinear governing equations for the HSLA steel circular plate are obtained by using the kirchhoff hypothesis. The unknown variable functions are discrete in space and time domains by utilizing the finite difference method and Newmark method, the whole problem is solved by the iterative method. Numerical results indicate that some of the important geometrical and physical parameters are important factors affecting the dynamic response of the HSLA steel circular plate and the design of structures.
- Published
- 2014
30. Mechanical and acoustic response of an underwater structure subjected to mechanical excitation
- Author
-
Xue-Tao Weng, Yiming Fu, Hong-Liang Dai, Yiqi Mao, and Shi-Jian Zhu
- Subjects
Materials science ,Mechanical Engineering ,Acoustics ,Computational Mechanics ,Shell (structure) ,engineering.material ,Functionally graded material ,Core (optical fiber) ,symbols.namesake ,Coating ,Mechanics of Materials ,Helmholtz free energy ,engineering ,symbols ,Underwater ,Galerkin method ,Boundary element method - Abstract
In this paper, an underwater structure is modeled as a cylindrical shell with internal bulkheads, and closed by a truncated conical shell, and it consists of metal substrate and sound absorbing coating, whose FGM core is considered. Suppose the inner cavity and outer space of the structure are filled with air and fluid mediums, the mechanical response of the underwater structure is calculated with Galerkin method while the acoustic response is investigated by means of the Helmholtz integral. Some numerical examples are given and the effect of geometrical size and material parameters on mechanical and acoustic response is discussed.
- Published
- 2014
31. Investigation on thermomechanical behavior of a HSLA steel circular plate under impact load
- Author
-
Xiang Yan, Hao-Jie Jiang, and Hong-Liang Dai
- Subjects
Materials science ,Physics::Instrumentation and Detectors ,business.industry ,Mechanical Engineering ,Finite difference method ,Structural engineering ,Föppl–von Kármán equations ,Contact force ,Contact mechanics ,Mechanics of Materials ,Plate theory ,Solid mechanics ,General Materials Science ,Newmark-beta method ,Deformation (engineering) ,business - Abstract
Based on the von Karman equation and classical thin plate theory, thermomechanical behavior of a high strength low alloy (HSLA) steel circular plate under impact load is investigated. Firstly, when the HSLA steel circular plate is impacted by a rigid impactor, the relation of the contact radius and the instantaneous relative displacement is obtained by using the modified nonlinear Hertzian contact law, and the contact force is solved by using the time increment method. Secondly, the nonlinear governing equations in the form of displacements for the HSLA steel circular plate under the impact load are obtained by using the Hamilton variational principle. Finally, the unknown variable functions are discretized in space and time domains by utilizing the finite difference method and Newmark method, and the whole problem is solved by the iterative method. Numerical results denote that the geometrical parameters, boundary conditions of the HSLA steel circular plate and the initial velocity of impactor have great influences on deformation, the contact force and stresses of the HSLA steel circular plate.
- Published
- 2014
32. Analysis for the thermoelastic bending of a functionally graded material cylindrical shell
- Author
-
Ting Dai and Hong-Liang Dai
- Subjects
Materials science ,Mechanical load ,Mechanical Engineering ,Nuclear Theory ,Mechanics ,Condensed Matter Physics ,Functionally graded material ,Mathematics::Numerical Analysis ,Transverse plane ,Exact solutions in general relativity ,Thermoelastic damping ,Mechanics of Materials ,Deflection (engineering) ,Thermal ,Physics::Atomic and Molecular Clusters ,Boundary value problem - Abstract
An analytic study for thermoelastic bending of a functionally graded material (FGM) cylindrical shell subjected to a uniform transverse mechanical load and non-uniform thermal loads is presented. Based on the classical linear shell theory, the equations with the radial deflection and horizontal displacement are derived out. An arbitrary material property of the FGM cylindrical shell is assumed to vary through the thickness of the cylindrical shell, and exact solution of the problem is obtained by using an analytic method. For the FGM cylindrical shell with fixed and simply supported boundary conditions, the effects of mechanical load, thermal load and the power law exponent on the deformation of the FGM cylindrical shell are analyzed and discussed.
- Published
- 2013
33. Creep buckling and post-buckling analyses for a hybrid laminated viscoelastic FGM cylindrical shell under in-plane loading
- Author
-
Hong-Liang Dai, Hong-Yan Zheng, and Ting Dai
- Subjects
Materials science ,business.industry ,Mechanical Engineering ,Finite difference method ,Structural engineering ,Functionally graded material ,Viscoelasticity ,Condensed Matter::Soft Condensed Matter ,Nonlinear system ,Buckling ,Creep ,Mechanics of Materials ,Deflection (engineering) ,Solid mechanics ,General Materials Science ,Composite material ,business - Abstract
In this paper, creep buckling and post-buckling of a hybrid laminated viscoelastic functionally graded material (FGM) cylindrical shell under in-plane loading are investigated. Considering the high-order transverse shear deformation and geometric nonlinear theory, the von Karman geometric relation of the hybrid laminated viscoelastic FGM cylindrical shell with initial deflection is established. Based on the Donnell theory, elastic piezoelectric theory and Boltzmann superposition principle, nonlinear creep governing equations of the hybrid laminated viscoelastic FGM cylindrical shell under in-plane loading are derived. By means of the finite difference method and the Newton–Newmark method, the problem for creep buckling and post-buckling of the laminated shell’s structure is solved. Numerical results are presented to show effects of geometric parameters, power law index and loading on creep buckling and post-buckling of the hybrid laminated viscoelastic FGM cylindrical shell.
- Published
- 2013
34. Free vibration of a FGPM circular plate placed in a uniform magnetic field
- Author
-
Hong-Liang Dai, Lei Yang, and Ting Dai
- Subjects
Vibration ,Materials science ,Mechanics of Materials ,Transverse isotropy ,Mechanical Engineering ,Mathematical analysis ,Geometry ,Boundary value problem ,Condensed Matter Physics ,Material properties ,Piezoelectricity ,Magnetic field ,Exponential function - Abstract
In this paper, free vibration of a circular plate composed of a transversely isotropic functionally graded piezoelectric material (FGPM) placed in a uniform magnetic field is investigated. Material properties are assumed to depend on the thickness of the circular plate and they are expressed as the same exponential function of h. The problem of free vibration for the transversely isotropic FGPM circular plate with clamped and simply supported boundary conditions is solved by means of the state space method. Numerical examples and some useful discussions are given to demonstrate the significant influence of material inhomogeneity, and adopting a certain value of the graded index can optimize structures of the circular plate. This will be of particular importance in modern engineering design.
- Published
- 2013
35. Coil-globule transition of a single semiflexible chain in slitlike confinement
- Author
-
Jie Yan, C. Benjamin Renner, Liang Dai, Patrick S. Doyle, Massachusetts Institute of Technology. Department of Chemical Engineering, Renner, C. Benjamin, and Doyle, Patrick S.
- Subjects
chemistry.chemical_classification ,Quantitative Biology::Biomolecules ,Phase transition ,Lattice model (finance) ,Work (thermodynamics) ,Multidisciplinary ,Materials science ,Polymers ,Coil-globule transition ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Critical value ,DNA condensation ,01 natural sciences ,Attraction ,Phase Transition ,Article ,0104 chemical sciences ,chemistry ,Chemical physics ,Thermodynamics ,0210 nano-technology ,Algorithms - Abstract
Single polymer chains undergo a phase transition from coiled conformations to globular conformations as the effective attraction between monomers becomes strong enough. In this work, we investigated the coil-globule transition of a semiflexible chain confined between two parallel plates, i.e. a slit, using the lattice model and Pruned-enriched Rosenbluth method (PERM) algorithm. We find that as the slit height decreases, the critical attraction for the coil-globule transition changes non-monotonically due to the competition of the confinement free energies of the coiled and globular states. In wide (narrow) slits, the coiled state experiences more (less) confinement free energy, and hence the transition becomes easier (more difficult). In addition, we find that the transition becomes less sharp with the decreasing slit height. Here, the sharpness refers to the sensitivity of thermodynamic quantities when varying the attraction around the critical value. The relevant experiments can be performed for DNA condensation in microfluidic devices., Singapore-MIT Alliance for Research and Technology Center, National Science Foundation (U.S.) (CBET-1335938)
- Published
- 2015
36. Stresses distributions in a rotating functionally graded piezoelectric hollow cylinder
- Author
-
Hong-Yan Zheng, Ting Dai, and Hong-Liang Dai
- Subjects
Materials science ,Hollow cylinder ,Mechanical Engineering ,Rotational symmetry ,Geometry ,Mechanics ,Condensed Matter Physics ,Piezoelectricity ,Power law ,Mechanics of Materials ,Thermal ,Radial displacement ,Electric potential ,Constant angular velocity - Abstract
An analytic solution to the axisymmetric problem of a long, radially polarized, hollow cylinder composed of functionally graded piezoelectric material (FGPM) rotating about its axis at a constant angular velocity is presented. For the case that electric, thermal and mechanical properties of the material obey different power laws in the thickness direction, distributions for radial displacement, stresses and electric potential in the FGPM hollow cylinder are determined by using the theory of electrothermoelasticity. Some useful discussions and numerical examples are presented to show the significant influence of material nonhomogeneity, and adopting suitable graded indexes and applying suitable geometric size and rotating velocity ω may optimize the rotating FGPM hollow cylindrical structures. This will be of particular importance in modern engineering application.
- Published
- 2011
37. DFT study of the reactions of Mo and Mo + with CO2 in gas phase
- Author
-
J.B. Wu, Chuan-Feng Wang, Deman Han, Ai-Guo Zhong, Hua Yan, Guo-Liang Dai, and Hao Chen
- Subjects
Exothermic reaction ,Reaction mechanism ,Energy profile ,Chemistry ,Computational chemistry ,Atom ,Potential energy surface ,Molecule ,Density functional theory ,General Chemistry ,Potential energy - Abstract
Density functional theory (DFT) calculations have been performed to explore the potential energy surfaces of C–O bond activation in CO2 molecule by gas-phase Mo + cation and Mo atom, in order to better understanding the mechanism of second-row metal reacting with CO2. The minimum energy reaction path is found to involve the spin inversion in the different reaction steps. This potential energy curve-crossing dramatically affects reaction exothermic. The present results show that the reaction mechanism is insertion-elimination mechanism along the C–O bond activation branch. All the theoretical results not only support the existing conclusions inferred from early experiment, but also complement the pathway and mechanism for this reaction.
- Published
- 2011
38. Correction to: Development and Cross-Cultural Validity of a Brief Measure of Separation-Individuation
- Author
-
George B. Richardson, Ching-Chen Chen, Mark H. C. Lai, Danica G. Hays, and Chia-Liang Dai
- Subjects
Development (topology) ,Developmental and Educational Psychology ,Separation individuation ,Measure (physics) ,Cross-cultural ,Mistake ,Life-span and Life-course Studies ,Psychology ,Cognitive psychology - Abstract
The original version of this article unfortunately contained a mistake. The title was incorrect. The correct title is “Development and Cross-Cultural Validity of a Brief Measure of Separation-Individuation”. The original article has been corrected.
- Published
- 2018
39. Exact Electromagnetothermoelastic Solution for a Transversely Isotropic Piezoelectric Hollow Sphere Subjected to Arbitrary Thermal Shock
- Author
-
Lei Yang, Hong-Yan Zheng, and Hong-Liang Dai
- Subjects
Hankel transform ,Laplace transform ,Mechanical Engineering ,Mathematical analysis ,Volterra integral equation ,Piezoelectricity ,Magnetic field ,symbols.namesake ,Mechanics of Materials ,Transverse isotropy ,symbols ,General Materials Science ,Electric potential ,Electric displacement field ,Mathematics - Abstract
This paper presents analytical study for electromagnetothermoelastic transient behavior of a transversely isotropic hollow sphere, placed in a uniform magnetic field, subjected to arbitrary thermal shock. Exact solutions for the transient responses of stresses, perturbation of magnetic field vector, electric displacement and electric potential in the transversely isotropic piezoelectric hollow sphere are obtained by means of the Hankel transform, the Laplace transform and their inverse transforms. An interpolation method is used to solve the Volterra integral equation of the second kind caused by interactions among electric, magnetic, thermal and elastic fields. From the sample numerical calculations, it is seen that the present method is suitable for the transversely isotropic hollow sphere, placed in a uniform magnetic field, subjected to arbitrary thermal shock. Finally, the result can be used as a reference to solve other transient coupling problems of electromagnetothermoelasticity.
- Published
- 2010
40. Robust digital audio watermarking scheme using blind source separation with global optimal property
- Author
-
Hua-liang Dai and Di He
- Subjects
Multidisciplinary ,Modified discrete cosine transform ,Second-generation wavelet transform ,Speech recognition ,Computer Science::Multimedia ,Discrete cosine transform ,FastICA ,Watermark ,Algorithm ,Blind signal separation ,Independent component analysis ,Transform coding ,Mathematics - Abstract
The paper proposes a robust digital audio watermarking scheme using blind source separation (BSS) based on the global optimization of independency metric (IM), which is formulated as a generalized eigenvalue (GE) problem. Compared with traditional information-theoretical approaches used in digital audio watermarking, such as fast independent component analysis (FastICA), the proposed scheme has lower complexity without time-consuming iteration steps used in FastICA. To make full use of the multiresolution characteristic of discrete wavelet transform (DWT) and the energy compression characteristic of discrete cosine transform (DCT), the watermark is embedded in the middle DWT-DCT coefficients and the independent component analysis (ICA) approach based on IM is used in the detecting scheme. Simulation results based on Stirmark for Audio v02 show that the proposed scheme has strong robustness as well as the imperceptibility and security.
- Published
- 2010
41. Interaction Between Levamisole Hydrochloride and Bovine Serum Albumin and the Influence of Alcohol: Spectra
- Author
-
Lin Weng, Fuyou Pan, Huading Liang, Jianguo Yang, Hua Yan, Guo-Liang Dai, Songlin Zhao, and Xiandi Zhu
- Subjects
Quenching (fluorescence) ,biology ,Stereochemistry ,Hydrogen bond ,Chemistry ,Biophysics ,Tryptophan ,Serum albumin ,Biochemistry ,Binding constant ,symbols.namesake ,Combination reaction ,symbols ,biology.protein ,Physical chemistry ,Physical and Theoretical Chemistry ,van der Waals force ,Bovine serum albumin ,Molecular Biology - Abstract
The interaction between levamisole hydrochloride (LH) and bovine serum albumin, BSA, has been studied by a spectral method under physiological conditions. For 1:n complexes, the relationship between fluorescence quenching intensity and concentration of the quenchers can be deduced on the basis of the modified Stern–Volmer equation. The binding constants and corresponding thermodynamic parameters ΔHm, ΔGm and ΔSm at different temperatures were calculated. The experimental results demonstrated that the combination reaction of LH and BSA was a static quenching process because a 1:1 complex was formed, and the main dominant binding forces were hydrogen bonding and van der Waals forces. Meanwhile, the polarity of the tyrosine residue (Tyr) or tryptophan residue (Trp) micro-region was not obviously affected by the interaction. Furthermore, the binding constant increase when alcohol was added.
- Published
- 2009
42. Optimizing P2P streaming throughput under peer churning
- Author
-
Liang Dai, Yanchuan Cao, Yuan Xue, and Yi Cui
- Subjects
Computer Networks and Communications ,Computer science ,Distributed computing ,Code rate ,Admission control ,Peer-to-peer ,Churning ,computer.software_genre ,Shared resource ,Hardware and Architecture ,Computer Science::Networking and Internet Architecture ,Media Technology ,Online algorithm ,computer ,Throughput (business) ,Selection algorithm ,Software ,Simulation ,Information Systems - Abstract
High-throughput P2P streaming relies on peer selection, the strategy a peer uses to select other peer(s) as its parent(s) of streaming. Although this problem has been thoroughly investigated in the classical optimization framework under static settings, it still remains unaddressed as how to sustain throughput competitive to the optimum under highly dynamic peer churning. To accommodate such peer dynamics, we extend the classical optimization framework and propose a distributed online peer selection algorithm. This basic algorithm is further extended to a variety of settings commonly seen in operational P2P networks, such as multi-parent streaming, admission control, delay constraint, etc. We prove approximation bound of our algorithm to the optimal throughput. Through evaluation under different topological setups and peer churning sequences, we show that our solution can consistently deliver competitive throughput, which greatly outperforms its theoretical bound.
- Published
- 2008
43. Optimal Routing for Wireless Mesh Networks With Dynamic Traffic Demand
- Author
-
Bin Chang, Liang Dai, Yi Cui, Yanchuan Cao, and Yuan Xue
- Subjects
Dynamic Source Routing ,Static routing ,Wireless mesh network ,Computer Networks and Communications ,Computer science ,business.industry ,Distributed computing ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Policy-based routing ,Wireless Routing Protocol ,Link-state routing protocol ,Hardware and Architecture ,Multipath routing ,Hazy Sighted Link State Routing Protocol ,business ,Software ,Information Systems ,Computer network - Abstract
Wireless mesh networks have attracted increasing attention and deployment as a high-performance and low-cost solution to last-mile broad-band Internet access. Traffic routing plays a critical role in determining the performance of a wireless mesh network. To investigate the best routing solution, existing work proposes to formulate the mesh network routing problem as an optimization problem. In this problem formulation, traffic demand is usually implicitly assumed as static and known a priori. Contradictorily, recent studies of wireless network traces show that the traffic demand, even being aggregated at access points, is highly dynamic and hard to estimate. Thus, in order to apply the optimization-based routing solution into practice, one must take into account the dynamic and unpredictable nature of wireless traffic demand. This paper presents an integrated framework for wireless mesh network routing under dynamic traffic demand. This framework consists of two important components: traffic estimation and routing optimization. By studying the traces collected at wireless access points, we first present a traffic estimation method which predicts future traffic demand based on its historical data using time-series analysis. This method provides not only the mean value of the future traffic demand estimation but also its statistical distribution. We further investigate the optimal routing strategies for wireless mesh network which take these two forms of traffic demand estimations as inputs. The goal is to balance the traffic load so that minimum congestion will be incurred. This routing objective could be transformed into the throughput optimization problem where the throughput of aggregated flows is maximized subject to fairness constraints that are weighted by the traffic demands. Based on linear programming, we present two routing algorithms which consider the mean value and the statistical distribution of the predicted traffic demands, respectively. The trace-driven simulation study demonstrates that our integrated traffic estimation and routing optimization framework can effectively incorporate the traffic dynamics in mesh network routing.
- Published
- 2008
44. Characteristics and method of synthesis seismic wave based on wavelet reconstruction
- Author
-
Xin Shang, Ai-ping Liu, Bo Dong, Xin-jian Chai, Hong Yang, Su-liang Dai, and Li-hua Zou
- Subjects
Engineering ,Synthetic seismogram ,business.industry ,Acoustics ,Dispersive body waves ,Seismic noise ,Geotechnical Engineering and Engineering Geology ,Seismic wave ,Physics::Geophysics ,Wavelet packet decomposition ,Geophysics ,Wavelet ,Seismic inversion ,Harmonic wavelet transform ,business - Abstract
A novel method of synthesizing seismic wave using wavelet reconstruction is proposed and compared with the traditional method of using theory of Fourier transform. By adjusting the frequency band energy and taking it as criterion, the formula of synthesizing seismic wave is deduced. Using the design parameters specified in Chinese Seismic Design Code for buildings, seismic waves are synthesized. Moreover, the method of selecting wavelet bases in synthesizing seismic wave and the influence of the damping ratio on synthesizing results are analyzed. The results show that the synthesis seismic waves using wavelet bases can represent the characteristics of the seismic wave as well as the ground characteristic period, and have good time-frequency non-stationary.
- Published
- 2007
45. Low voltage actuated RF micromechanical switches fabricated using CMOS-MEMS technique
- Author
-
Jing-Han Chen and Ching-Liang Dai
- Subjects
Fabrication ,Materials science ,business.industry ,Coplanar waveguide ,Capacitive sensing ,Electrical engineering ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,CMOS ,Hardware and Architecture ,Transmission line ,Radio frequency ,Electrical and Electronic Engineering ,business ,Low voltage ,Voltage - Abstract
This study investigates the fabrication of radio frequency (RF) micromechanical switches with low actuation voltage using the commercial 0.35 μm double polysilicon four metal (DPFM) complementary metal oxide semiconductor (CMOS) process and the post-process. The advantages of RF micromechanical switches include low pull-down voltage and ease of post-processing. Three types of RF micromechanical switches are designed and manufactured. The RF switches are capacitive type, and the structures of the switches comprise coplanar waveguide (CPW) transmission lines, supported springs and a suspended membrane. The post-process requires only a wet etching silicon dioxide layer. Experimental results show that type-c switch needs only a pull-down voltage of 7 V.
- Published
- 2006
46. Non-Linear Dynamic Response of a Single Wall Carbon Nanotube Subjected to Radial Impulse
- Author
-
Hong-Liang Dai and Xiaohu Wang
- Subjects
Materials science ,Mechanical Engineering ,Linear system ,Principal point ,Carbon nanotube ,Impulse (physics) ,Curvature ,law.invention ,Non linear dynamic ,Physics::Fluid Dynamics ,Condensed Matter::Materials Science ,Nonlinear system ,Flexural strength ,law ,Physics::Atomic and Molecular Clusters ,Composite material - Abstract
This paper investigates non-linear dynamic response of a single wall carbon nanotube (CNT) based on a thin-walled shell mode. Following the subsequent motion of a single wall (CNT) under radial impulsive pressure, a nonlinear dynamic response may occur through interaction of circumferential membrane force with flexural curvature. The results carried out show that the initial deformation energy in the single wall CNT will be transferred, over a number of cycles, from the breathing mode to one or two high flexural modes, so that the nonlinear flexural stress of the single wall CNT is significantly higher than that given by linear theory. The principal point of interest are the conditions for significant interaction to occur and the increased flexural stress associated with the altered radial motion of a single wall CNT.
- Published
- 2006
47. Dynamic focusing effect of piezoelectric fibers subjected to thermal shock
- Author
-
Hong-Liang Dai and X. Wang
- Subjects
Condensed Matter::Materials Science ,Thermal shock ,Amplitude ,Piezoelectric coefficient ,Materials science ,Piezoelectric sensor ,Mechanical Engineering ,Fiber ,Transient (oscillation) ,Composite material ,Piezoelectricity ,Computer Science::Other ,Dynamic stress - Abstract
Based on finite Hankle transforms, this paper presents a theoretical method for analyzing the dynamic focusing effect of piezoelectric fibers subjected to the thermal shock of a transitory temperature change produced by a sudden electric current pulse. From analytical expressions and example calculations for two kinds of piezoelectric fibers, PZT-4 and BaTiO3, it is found that the dynamic focusing effect is dependent on the material property of the piezoelectric fibers so that the maximum dynamic stress amplitude of the two kinds of piezoelectric fiber occur at different radial points. The mechanism of the dynamic focusing effect in piezoelectric fibers is relevant to the evaluation of the dynamic strength and electric signal of the piezoelectric fiber. The results carried out may be used as a reference to solve other transient coupled electrothermoelasticity problems in piezoelectric structures.
- Published
- 2006
48. A micromachined tunable resonator fabricated by the CMOS post-process of etching silicon dioxide
- Author
-
Ching-Liang Dai and Wei-Chiang Yu
- Subjects
Materials science ,Fabrication ,business.industry ,Silicon dioxide ,Interdigital transducer ,Electrical engineering ,Condensed Matter Physics ,Isotropic etching ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Resonator ,chemistry ,CMOS ,Hardware and Architecture ,Etching (microfabrication) ,Optoelectronics ,Electrical and Electronic Engineering ,business ,Voltage - Abstract
This work investigates the fabrication of a micromechanical tunable resonator using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process and the post-process of only one maskless wet etching. The post-process has advantages of easy execution and low cost. The post-process employs an etchant (silox vapox III) to etch the silicon dioxide layer to release the suspended structures of the resonator. The tunable resonator comprises a driving unit, a tuning unit and a sensing unit. The resonant frequency of the resonator can be tuned using a dc-biased electrostatic comb of linearly varied finger-length. Experimental results show that the resonant frequency of the resonator is about 4.8 kHz, and it has a frequency-tuning range of 6.8% at the tuning voltage of 0–25 V.
- Published
- 2006
49. A circular micromirror array fabricated by a maskless post-CMOS process
- Author
-
Ping-Hei Chen, Pei-Zen Chang, C.-Y. Lee, Ching-Liang Dai, and Ying-Chou Cheng
- Subjects
Materials science ,Fabrication ,business.industry ,Natural frequency ,Surface finish ,Condensed Matter Physics ,Chip ,Electronic, Optical and Magnetic Materials ,Optics ,CMOS ,Hardware and Architecture ,Electrode ,Charge pump ,Electrical and Electronic Engineering ,business ,Voltage - Abstract
This work studies the fabrication of a circular micromirror array by the standard 0.35 μm SPFM (Single Polysilicon Four Metals) CMOS (complementary metal oxide semiconductor) process and a maskless postprocess. The advantages of the post-process are its compatibility with conventional CMOS process and this method provides a way to designer to quickly construct micromachined structures using the standardized procedures. The mentioned circular micromirror array that contains 10 × 10 micromirror switches is integrated with a 1 × 8 de-multiplexer control circuit and a four-stage charge pump on a chip. The radius of each micromirror is about 25 im, and the gap from the bottom electrode to the top mirror plate is about 5 μm. The micromirror array is actuated using an electrostatic force. Simulated results show that the micromirror has a tilting angle of around 9° at a driving voltage of 30 V. The root-mean-square roughness and the average roughness of the mirror surface are measured at 15.31 nm and 12.58 nm respectively. In addition, the first and the second mode of natural frequency of the micromirror switch are around 492 KHz and 508 KHz, respectively.
- Published
- 2005
50. Assignment of humansprouty 4 gene to chromosome segment 5q32∼33 and analysis of its pattern of expression
- Author
-
Yu Min Mao, Hua Liu, Xie Yi, Lu Huang, Jian Liang Dai, Jin Zhong Chen, Wang Xiang Xu, Shao Hua Gu, and En Pang Zhao
- Subjects
medicine.anatomical_structure ,Chromosome Band ,Placenta ,Genetics ,medicine ,Chromosome ,Skeletal muscle ,Northern blot ,Biology ,Primer (molecular biology) ,Molecular biology ,Gene ,Small intestine - Abstract
The humansprouty 4 (SPYR4) gene was localized to chromosome band 5q32∼33 by screening the Stanford radiation hybrid G3 panel using aSPRY4-specific primer pair for PCR. Northern blot analysis revealed two different mRNAs (5 kb and 2 kb) in liver, skeletal muscle, heart, lung, kidney, spleen, placenta and small intestine. Reverse transcriptase-PCR analysis showed thatSPYR4 was expressed in all tested tissues to different levels.
- Published
- 2003
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