37 results on '"Xiaowei Yang"'
Search Results
2. Liquid-Mediated Dense Integration of Graphene Materials for Compact Capacitive Energy Storage.
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Xiaowei Yang, Chi Cheng, Yufei Wang, Ling Qiu, and Dan Li
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SUPERCAPACITOR electrodes , *CARBON electrodes , *POROUS electrodes , *ENERGY storage , *ELECTRIC properties of graphene , *ELECTROLYTE solutions , *GRAPHENE - Abstract
Porous yet densely packed carbon electrodes with high ion-accessible surface area and low ion transport resistance are crucial to the realization of high-density electrochemical capacitive energy storage but have proved to be very challenging to produce. Taking advantage of chemically converted graphene's intrinsic microcorrugated two-dimensional configuration and self-assembly behavior, we show that such materials can be readily formed by capillary compression of adaptive graphene gel films in the presence of a nonvolatile liquid electrolyte. This simple soft approach enables subnanometer scale integration of graphene sheets with electrolytes to form highly compact carbon electrodes with a continuous ion transport network. Electrochemical capacitors based on the resulting films can obtain volumetric energy densities approaching 60 watt-hours per liter. [ABSTRACT FROM AUTHOR]
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- 2013
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3. Preparation of (Ba,Sr)TiO3@polystrene core-shell nanoparticles by solvent-free surface-initiated atom transfer radical polymerization
- Author
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Xiaowei, Yang, Yanwei, Zeng, Tongxiang, Cai, and Zhenxing, Hu
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BARIUM strontium titanate , *POLYSTYRENE , *STRUCTURAL shells , *NANOPARTICLES , *ATOM transfer reactions , *ADDITION polymerization , *NANOCRYSTALS , *MICROWAVES , *SOLVENTS , *FOURIER transform infrared spectroscopy - Abstract
Abstract: The polystyrene shells have been successfully grown on the barium strontium titanate (BST) nanocrystals, which were synthesized by microwave-activated glycothermal method, via a solvent-free surface-initiated atom transfer radical polymerization (SI-ATRP) after the 2-bromo-2-methylpropionic acid molecules (Br-MPA) were anchored at the surface of BST nanocrystals through ligand exchange with hydroxyl groups on their surfaces. These surface modified BST nanocrystals can then be perfectly dispersed in styrene monomer and act as macroinitiators for ATRP to yield BST@PS core-shell structured nanoparticles, which endow the BST nanocrystals with exceptionally good dispersibility and stability in hydrophobic solvents. The BST@PS core-shell structures were characterized by X-ray diffraction (XRD) technique and transmission electron microscopy (TEM). Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy (Raman), differential scanning calorimetry (DSC) and gel permeation chromatography were also employed to probe the Br-MPA and PS on the BST nanocrystals. It has been shown that after the BST nanocrystals are surface-modified with Br-MPA, the polymerization of styrene can steadily occur at the surface of BST nanocrystals to form a uniform polystyrene shell and its thickness can reach ∼10nm when the polymerization reaction is extended to 36h, while no changes are found to take place with the BST nanocrystals. Compared with typical high molecular weight PS (M n =6700), the as-obtained PS possess a relatively low molecular weight (M n =5473) and a lower glass transition temperature (T g ∼93°C). The research results demonstrate a viable strategy for the preparation of polymer-coated functional metal oxides nanocrystals, potentially useful in biological and nanoelectronic applications. [Copyright &y& Elsevier]
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- 2012
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4. Changes in Practice and Reconstruction of Theory.
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Xiaowei, Yang
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PRIMARY school teaching , *MIDDLE school teaching , *EDUCATION , *CURRICULUM change , *EDUCATIONAL change , *TEACHING , *ETHICS , *HISTORY - Abstract
The reforms of middle and primary school teaching that have been launched in mainland China over the past thirty years have been manifested in different ways and in different periods of time. The first to appear were localized and scattered teaching reforms oriented toward efficiency, after which commenced explorative teaching experiments in pursuit of scientizing. Then, with the rise of basic education curriculum reform, "three-dimensional targets" became a new focus of attention. Recently, the focus has been on teaching reform conducted in accordance with school transformation. In the future, the foundation-laying significance of teaching will be understood from the perspective of lifelong learning and development, and "curriculum research based on teaching" will take up the challenge of curriculum theory development. [ABSTRACT FROM AUTHOR]
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- 2012
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5. Electrochemical behavior of gold (III) in cyanide-free bath with 5,5′-dimethylhydantoin as complexing agent
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Xiaowei, Yang, Maozhong, An, Yunwang, Zhang, and Lin, Zhang
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ELECTROFORMING , *GOLD compounds , *METAL complexes , *CYANIDES , *METHYLHYDANTOIN , *ELECTROCHEMICAL analysis , *NUCLEATION , *ELECTROLYTIC oxidation - Abstract
Abstract: Gold electrodeposits are prepared in a cyanide-free bath with 5,5′-dimethylhydantoin (DMH) as complexing agent. The electrochemical behavior of the electrodeposition is then investigated together with the influence of additive A (pyridyl-compound) as an additive on the nucleation and growth of gold using electrochemical techniques on gold working electrode at different temperatures. Cyclic voltammogram consists of a single cathodic reduction wave at −0.62V which corresponds to the reduction of Au(III) to Au without anodic oxidation wave observed. The diffusion coefficient of Au(III) in the bath is found to be ∼10−6 cm2/s and the energy of activation (43kJ/mol) is deduced from the cyclic voltammograms at different temperatures. The nucleation and growth of gold on gold working electrode is investigated by chronoamperometry. The progressive nucleation mechanism is found for gold deposition using Scharifker–Hills’ model with three-dimensional (3D) diffusion-controlled growth nucleation. The introduction of the additive A does not influence this mechanism. The gold electrodeposits are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and cathodic polarization measurements. Experimental results indicate that additive A increases the cathodic polarization of bath, refines the grains of electrodeposit and changes the preferred orientation of electrodeposit from [111] direction to [200] direction. [Copyright &y& Elsevier]
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- 2011
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6. Oleic acid assisted glycothermal synthesis of cuboidal Ba0.6Sr0.4TiO3 nanocrystals and their ordered architectures via self-assembly
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Xiaowei, Yang, Yanwei, Zeng, Leiqing, Mo, and Longxiang, Han
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OLEIC acid , *ORGANIC synthesis , *STRONTIUM compounds , *NANOCRYSTALS , *MOLECULAR self-assembly , *CRYSTAL growth , *BARIUM compounds , *ORGANIC solvents , *CHEMICAL processes - Abstract
Abstract: The size-controllable and highly monodispersed cuboidal barium strontium titanate (BST) nanocrystals have been successfully synthesized through a glycothermal process with no mineralizers but oleic acid as growth-directing agent. The synthesized BST nanocrystals under different glycothermal conditions were structurally characterized by XRD, IR, FESEM, TEM and HRTEM and investigated with respect to the effects of key influencing factors including the amount of oleic acid, duration of glycothermal process and 1,4-butanediol/water volume ratio in the reaction media on the formation of BST nanocrystals and their size and morphological evolution. It has been found that the oleic acid incorporated into the glycothermal system plays a decisive role in promoting the formation of cuboidal nanocrystals. It allows the BST nanocrystals to form via a nucleation-growth mechanism instead of in situ reactions and the selective chemical adsorption of oleic acid molecules on the facets with lower plane indices of newly-built BST nuclei directs them to grow into uniform cuboidal BST nanocrystals. The duration of glycothermal reactions and the polarity of reaction media can remarkably affect the dynamic process of the formation of BST nanocrystals. These regularly-shaped and highly monodispersed nanocrystals show a spontaneity of self-assembling into 2D ordered architectures when they were dispersed in organic solvents like cyclohexane and droped onto a hydrophobic surface of substrates, which creates a chance for the ferroelectric oxide nanocrystals to self-assemble into nanoscale electronic devices. [Copyright &y& Elsevier]
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- 2011
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7. An investigation of the effect of sodium dodecyl sulfate on quasi-emulsifier-free emulsion polymerization for highly monodisperse polystyrene nanospheres
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Zhenxing, Hu, Xiaowei, Yang, Junliang, Liu, Yuping, Yan, Ling, Wang, and Yanwei, Zeng
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SODIUM dodecyl sulfate , *POLYSTYRENE , *EMULSION polymerization , *NUCLEATION , *SURFACE active agents , *MICELLES , *NANOSTRUCTURED materials - Abstract
Abstract: A quasi-emulsifier-free emulsion polymerization for the synthesis of highly monodisperse polystyrene (PS) microspheres with the diameter less than 100nm has been developed, which is similar to the conventional emulsifier-free emulsion polymerization except for the addition of a small amount of sodium dodecyl sulfate (SDS) below its critical micelle concentration. To study the effect of SDS on the polymerization, we first explored the nucleation mechanism, and supposed that mixed micelles of SDS and surface active styrene oligomers may be formed and provide indispensable loci for the growth of PS primary particles. As the precursor particles grow, they become unstable and tend to adsorb the rest of SDS not participating in the formation of mixed micelles on their surfaces. Thereby, it reduces the coagulation tendency of the particles, and results in a significant increase of the particle number density which was found to be directly proportional to the square of the surfactant concentration, along with the increase of the polymerization rate and the decrease of the size of final PS particles. In addition, the presence of the surfactant will shorten the duration of the nucleation and, thus, lead to the highly uniform size of PS nanospheres. [ABSTRACT FROM AUTHOR]
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- 2011
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8. Proteomic study of Mycoplasma suis using the gel-based shotgun strategy
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Congli, Yuan, Xiaowei, Yang, Zhibiao, Yang, Ningyu, Zhu, Shenbo, Zheng, Peixing, Hou, Xiaofeng, Gu, Chengrong, Ye, Congbin, Yao, Jianguo, Zhu, Li, Cui, and Xiuguo, Hua
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PROTEOMICS , *MYCOPLASMA , *ERYTHROCYTES , *MYCOPLASMATALES , *NUCLEOTIDES , *BIOSYNTHESIS , *LIQUID chromatography - Abstract
Abstract: Mycoplasma suis (M. suis) is an uncultivable pathogen that colonizes the surface of porcine erythrocytes. In the present study, gel-based LC–MS/MS was performed to analyze the proteomic composition of M. suis. We identified 191 proteins with two or more peptides and additional 217 putative proteins with one peptide hit by cross-species searching the Mollicutes protein databases. Resultant proteins were classified based on their molecular functions. The majority of enzymes involved in central carbon metabolic pathways and nucleotide biosynthesis were confirmed by searching the KEGG database. The present study is the first report addressing the proteome of M. suis. Results indicate that the energy source of M. suis might depend mainly on glycometabolism. [Copyright &y& Elsevier]
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- 2010
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9. Adaptive pruning algorithm for least squares support vector machine classifier.
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Xiaowei Yang, Jie Lu, and Guangquan Zhang
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SUPPORT vector machines , *LEAST squares , *PRUNING , *MATHEMATICAL optimization , *MATHEMATICAL statistics - Abstract
a new version of support vector machine (SVM), least squares SVM (LS-SVM) involves equality instead of inequality constraints and works with a least squares cost function. A well-known drawback in the LS-SVM applications is that the sparseness is lost. In this paper, we develop an adaptive pruning algorithm based on the bottom-to-top strategy, which can deal with this drawback. In the proposed algorithm, the incremental and decremental learning procedures are used alternately and a small support vector set, which can cover most of the information in the training set, can be formed adaptively. Using this set, one can construct the final classifier. In general, the number of the elements in the support vector set is much smaller than that in the training set and a sparse solution is obtained. In order to test the efficiency of the proposed algorithm, we apply it to eight UCI datasets and one benchmarking dataset. The experimental results show that the presented algorithm can obtain adaptively the sparse solutions with losing a little generalization performance for the classification problems with no-noises or noises, and its training speed is much faster than sequential minimal optimization algorithm (SMO) for the large-scale classification problems with no-noises. [ABSTRACT FROM AUTHOR]
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- 2010
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10. Markov transition models for binary repeated measures with ignorable and nonignorable missing values.
- Author
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Xiaowei Yang, Shoptaw, Steven, Kun Nie, Juanmei Liu, and Belin, Thomas R.
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MARKOV processes , *DRUG addiction , *BIOMARKERS , *URINE , *CLINICAL trials , *COCAINE abuse , *SMOKING cessation - Abstract
Motivated by problems encountered in studying treatments for drug dependence, where repeated binary outcomes arise from monitoring biomarkers for recent drug use, this article discusses a statistical strategy using Markov transition model for analyzing incomplete binary longitudinal data. When the mechanism giving rise to missing data can be assumed to be ‘ignorable’, standard Markov transition models can be applied to observed data to draw likelihood-based inference on transition probabilities between outcome events. Illustration of this approach is provided using binary results from urine drug screening in a clinical trial of baclofen for cocaine dependence. When longitudinal data have ‘nonignorable’ missingness mechanisms, random-effects Markov transition models can be used to model the joint distribution of the binary data matrix and the matrix of missingness indicators. Categorizing missingness patterns into those for occasional or ‘intermittent’ missingness and those for monotonic missingness or ‘missingness due to dropout’, the random-effects Markov transition model was applied to a data set containing repeated breath samples analyzed for expired carbon monoxide levels among opioid-dependent, methadone-maintained cigarette smokers in a smoking cessation trial. Markov transition models provide a novel reconceptualization of treatment outcomes, offering both intuitive statistical values and relevant clinical insights. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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11. Imputation and Variable Selection in Linear Regression Models with Missing Covariates.
- Author
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Xiaowei Yang, Belin, Thomas R., and Boscardin, W. John
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REGRESSION analysis , *BAYESIAN analysis , *MATHEMATICAL models , *SIMULATION methods & models , *MULTIVARIATE analysis , *MENTAL health services - Abstract
Across multiply imputed data sets, variable selection methods such as stepwise regression and other criterion-based strategies that include or exclude particular variables typically result in models with different selected predictors, thus presenting a problem for combining the results from separate complete-data analyses. Here, drawing on a Bayesian framework, we propose two alternative strategies to address the problem of choosing among linear regression models when there are missing covariates. One approach, which we call “impute, then select” (ITS) involves initially performing multiple imputation and then applying Bayesian variable selection to the multiply imputed data sets. A second strategy is to conduct Bayesian variable selection and missing data imputation simultaneously within one Gibbs sampling process, which we call “simultaneously impute and select” (SIAS). The methods are implemented and evaluated using the Bayesian procedure known as stochastic search variable selection for multivariate normal data sets, but both strategies offer general frameworks within which different Bayesian variable selection algorithms could be used for other types of data sets. A study of mental health services utilization among children in foster care programs is used to illustrate the techniques. Simulation studies show that both ITS and SIAS outperform complete-case analysis with stepwise variable selection and that SIAS slightly outperforms ITS. [ABSTRACT FROM AUTHOR]
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- 2005
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12. An adaptive iteration algorithm for structural modal reanalysis of topological modifications.
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Xiaowei Yang, Huadong Lian, and Suhuan Chen
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ITERATIVE methods (Mathematics) , *ALGORITHMS , *PERTURBATION theory , *MATRICES (Mathematics) , *ADAPTIVE computing systems - Abstract
An adaptive iteration algorithm is presented in this paper for structural modal reanalysis of topological modifications. The rules of adaptation are given. The method is based on matrix perturbation and can be implemented easily on the computer. A little computation effort is involved, which is very important for topological modification with the increase of the joints and the number of degrees of freedom. In order to illustrate the method, three examples are given. The results show that the proposed method is effective for structural modal reanalysis of topological modifications. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
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- 2002
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13. A transcriptomic atlas of Aedes aegypti reveals detailed functional organization of major body parts and gut regional specializations in sugar-fed and blood-fed adult females.
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Hixson, Bretta, Xiao-Li Bing, Xiaowei Yang, Bonfini, Alessandro, Nagy, Peter, and Buchon, Nicolas
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AEDES aegypti , *ANOPHELES gambiae , *TRANSCRIPTOMES , *ANTIMICROBIAL peptides - Abstract
Mosquitoes transmit numerous pathogens, but large gaps remain in our understanding of their physiology. To facilitate explorations of mosquito biology, we have created Aegypti-Atlas (http://aegyptiatlas.buchonlab.com/), an online resource hosting RNAseq profiles of Ae. aegypti body parts (head, thorax, abdomen, gut, Malpighian tubules, ovaries), gut regions (crop, proventriculus, anterior and posterior midgut, hindgut), and a gut time course of blood meal digestion. Using Aegypti-Atlas, we provide insights into regionalization of gut function, blood feeding response, and immune defenses. We find that the anterior and posterior midgut possess digestive specializations which are preserved in the blood-fed state. Blood feeding initiates the sequential induction and repression/depletion of multiple cohorts of peptidases. With respect to defense, immune signaling components, but not recognition or effector molecules, show enrichment in ovaries. Basal expression of antimicrobial peptides is dominated by holotricin and gambicin, which are expressed in carcass and digestive tissues, respectively, in a mutually exclusive manner. In the midgut, gambicin and other effectors are almost exclusively expressed in the anterior regions, while the posterior midgut exhibits hallmarks of immune tolerance. Finally, in a cross-species comparison between Ae. aegypti and Anopheles gambiae midguts, we observe that regional digestive and immune specializations are conserved, indicating that our dataset may be broadly relevant to multiple mosquito species. We demonstrate that the expression of orthologous genes is highly correlated, with the exception of a 'species signature' comprising a few highly/disparately expressed genes. With this work, we show the potential of Aegypti-Atlas to unlock a more complete understanding of mosquito biology. [ABSTRACT FROM AUTHOR]
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- 2022
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14. Hybrid Reanalysis Method for Eigenproblems of Topological Modifications.
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Xiaowei Yang and Huandong Lian
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ELECTRIC network topology , *TOPOLOGY - Abstract
Focuses on a study which examined the hybrid reanalysis method for Eigenproblems of topological modifications. Problem formulation; Numerical examples; Conclusions.
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- 2002
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15. Building and leading a learning culture among teachers.
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Haiyan, Qian, Walker, Allan, and Xiaowei, Yang
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TEACHER-student relationships , *LEARNING ability , *SCHOOL boards , *CULTURAL values , *COLLEGE students , *HIGHER education ,EDUCATIONAL quality standards - Abstract
A positive teacher learning culture is important to effect meaningful changes in schools. Literature has established that successful school leaders can build and nurture learning cultures among teachers. However, less is known about how school leaders can shape the culture and make learning conditions happen at the schools in the Chinese education context. This paper reports an in-depth qualitative case study of a primary school in Shanghai. Using data collected from the principal, vice principal, mid-level leaders and teachers, the study attempts to answer these two questions: how do the school leaders build and nurture a positive teacher learning culture, and how does this culture affect teachers’ working lives? [ABSTRACT FROM AUTHOR]
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- 2017
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16. Optimization Design of the Ultra-High-Speed Vertical Rotor's Supporting Mechanism.
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Yongguang Liu, Xiaohui Gao, Xiaowei Yang, and Yixuan Wang
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MULTIDISCIPLINARY design optimization , *ROTORS , *VIBRATION (Mechanics) , *ACCELERATION (Mechanics) , *FINITE element method , *DEGREES of freedom - Abstract
How to increase the rotational speed and decrease vibration of the rotor in the acceleration has become an attractive subject, especially for the vertical rotors. This paper introduces a novel supporting mechanism to make the vertical rotor work at 80000 r/min smoothly. How to design and optimize the sensitive parameters of the supporting mechanism is the core problem to reduce the vibration in passing through critical speeds. Therefore, the FEM (finite element method) considering the gyroscopic couple is introduced to get the dynamic characteristic of the rotor system. The matching principle of the upper and lower supporting mechanism in the two-degree freedom system is extended to the multiple degree-freedom system, which is applied to optimize the parameters of the supporting mechanism combining with dynamic characteristic of the rotors system. At last, the rotor system can work at 80000 r/min smoothly in experiment. [ABSTRACT FROM AUTHOR]
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- 2014
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17. A new hybrid method for gene selection.
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Ruichu Cai, Zhifeng Hao, Xiaowei Yang, and Han Huang
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HYBRID systems , *DISCRIMINANT analysis , *DNA microarrays , *ANT algorithms , *GENE expression - Abstract
Gene selection is a significant preprocessing of the discriminant analysis of microarray data. The classical gene selection methods can be classified into three categories: the filters, the wrappers and the embedded methods. In this paper, a novel hybrid gene selection method (HGSM) is proposed by exploring both the mutual information criterion (filters) and leave-one-out-error criterion (wrappers) under the framework of an improved ant algorithm. Extensive experiments are conducted on three benchmark datasets and the results confirm the effectiveness and efficiency of HGSM. [ABSTRACT FROM AUTHOR]
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- 2011
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18. Robust least squares support vector machine based on recursive outlier elimination.
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Wen Wen, Zhifeng Hao, and Xiaowei Yang
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LEAST squares , *SUPPORT vector machines , *ALGORITHMS , *OUTLIERS (Statistics) , *ESTIMATION theory - Abstract
To achieve robust estimation for noisy data set, a recursive outlier elimination-based least squares support vector machine (ROELS-SVM) algorithm is proposed in this paper. In this algorithm, statistical information from the error variables of least squares support vector machine is recursively learned and a criterion derived from robust linear regression is employed for outlier elimination. Besides, decremental learning technique is implemented in the recursive training–eliminating stage, which ensures that the outliers are eliminated with low computational cost. The proposed algorithm is compared with re-weighted least squares support vector machine on multiple data sets and the results demonstrate the remarkably robust performance of the ROELS-SVM. [ABSTRACT FROM AUTHOR]
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- 2010
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19. Ethanol-assisted synthesis of Zn0.5Fe2.5O4 nanocrystals in thermal solvent of paraffin
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Xiangrong, Kong, Jun, Zang, Xiaowei, Yang, and Yanwei, Zeng
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DIELECTRICS , *ELECTRON microscopy , *SINTERING , *METALLIC composites - Abstract
Abstract: In the atmosphere of N2, low cost paraffin slices were refined and then successfully utilized as a solvent instead of the expensive high-carbon alkanes or alkenes like 1-octadecene to synthesize Zn0.5Fe2.5O4 nanocrystals at 320°C. In the experiments, the precursor solutions of ferric and zinc oleates were stoichiometrically prepared and injected by two-step operations into the hot solvent, together with controlled amounts of ethanol to tailor their thermal decomposition performances. The synthesized Zn0.5Fe2.5O4 nanocrystals were characterized by XRD and FESEM, having uniform morphology and a quasi-monodisperse size distribution with a mean value 25nm and a standard deviation of ±12.3%. The formation and structural characteristics of Zn0.5Fe2.5O4 nanocrystals are attributed to the catalysing function of ethanol and the effective separation of nucleation and growth of nanocrystals via the two-step injections of reactive precursors. [Copyright &y& Elsevier]
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- 2008
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20. Prenatal Exposure to Wood Fuel Smoke and Low Birth Weight.
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Siddiqui, Amna R., Gold, Ellen B., Xiaowei Yang, Kiyoung Lee, Brown, Kenneth H., and Bhutta, Zulfiqar A.
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LOW birth weight , *PREGNANT women , *FUELWOOD , *SMOKE , *FETAL development , *NATURAL gas , *COOKING education - Abstract
BACKGROUND: Maternal exposure to wood fuel smoke may lead to impaired fetal growth due to hypoxia and or oxidative stress from smoke constituents such as carbon monoxide and particulate matter. OBJECTIVES: We studied the risk of low birth weight (LBW) and reduced mean birth weight in relation to reported use of wood for cooking during the prenatal period, compared with natural gas (NG). METHODS: We studied a historical cohort of women who had a singleton live birth in the years 2000-2002, from a semirural area of Pakistan. Infant's birth weight was obtained from records, and prenatal records had data for maternal body mass index and parity. Cooking habits, daytime sleep habits, and type of fuel used during the pregnancies in 2000-2002 were ascertained by a survey done in 2004-2005. We performed multiple linear and logistic regression modeling using propensity scores to adjust for confounding variables. RESULTS: Unadjusted mean (± SD) birth weight was 2.78 ± 0.45 kg in wood users, and 2.84 ± 0.43 kg (p < 0.06) in NG users. Infants born to wood users averaged 82 g lighter than infants born to NG users when weight was adjusted for confounders (p < 0.07). The rate of LBW (< 2,500 g) was 22.7% among wood users compared with 15.0% in NG users (p < 0.01), for an adjusted relative risk of 1.64 (95% confidence interval, 1.10-2.34). The population attributable risk for LBW explained by wood use was estimated to be 24%. CONCLUSION: Cooking with wood fuel during pregnancy, a potentially modifiable exposure, was associated with LBW and marginally lower mean birth weight compared with using NG. [ABSTRACT FROM AUTHOR]
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- 2008
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21. Nesting Algorithm for Multi-Classification Problems.
- Author
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Bo Liu, Zhifeng Hao, and Xiaowei Yang
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ALGORITHMS , *LEAST squares , *FOUNDATIONS of arithmetic , *ALGEBRA - Abstract
Abstract Support vector machines (SVMs) are originally designed for binary classifications. As for multi-classifications, they are usually converted into binary ones. In the conventional multi-classifiable algorithms, One-against-One algorithm is a very power method. However, there exists a middle unclassifiable region. In order to overcome this drawback, a novel method called Nesting Algorithm is presented in this paper. Our ideas are as follows: firstly, construct the optimal hyperplanes based on One-against-One approach. Secondly, if there exist data points in the middle unclassifiable region, select them to construct the optimal hyperplanes with the same hyperparameters. Thirdly, repeat the second step until there are no data points in the unclassifiable region or the region is disappeared. In this paper, we also prove the validity of the proposed algorithm for unclassifiable region and give the computational complexity analysis of the method. In order to examine the training accuracy and the generalization performance of the proposed algorithm, One-against-One algorithm, fuzzy least square support vector machine (FLS-SVM) and the proposed algorithm are applied to five UCI datasets. The results show that the training accuracy of the proposed algorithm is higher than the others, and its generalization performance is also comparable with them. [ABSTRACT FROM AUTHOR]
- Published
- 2007
22. Structurally Tunable Reduced Graphene Oxide Substrate Maintains Mouse Embryonic Stem Cell Pluripotency.
- Author
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Jinping Zhao, Mingliang Tang, Jing Cao, Dan Ye, Xudong Guo, Jiajie Xi, Yi Zhou, Yuchen Xia, Jing Qiao, Renjie Chai, Xiaowei Yang, and Jiuhong Kang
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EMBRYONIC stem cells , *GRAPHENE oxide , *CELL communication , *STEM cell culture , *WNT signal transduction , *CELL size - Abstract
Culturing embryonic stem cells (ESCs) in vitro usually requires animal-derived trophoblast cells, which may cause pathogenic and immune reactions; moreover, the poor repeatability between batches hinders the clinical application of ESCs. Therefore, it is essential to synthesize a xenogeneic-free and chemically well-defined biomaterial substrate for maintaining ESC pluripotency. Herein, the effects of structurally tunable reduced graphene oxide (RGO) substrates with different physicochemical properties on ESC pluripotency are studied. Colony formation and CCK-8 assays show that the RGO substrate with an average 30 μm pore size promotes cell survival and proliferation. The unannealed RGO substrate promotes ESC proliferation significantly better than the annealed substrate due to the interfacial hydrophilic groups. The RGO substrate can also maintain ESC for a long time. Additionally, immunofluorescence staining shows that ESCs cultured on an RGO substrate highly express E-cadherin and β-catenin, whereas after being modified by Dickkopf-related protein 1, the RGO substrate is unable to sustain ESC pluripotency. Furthermore, the cell line that interferes with E-cadherin is also unable to maintain pluripotency. These results confirm that the RGO substrate maintains ESC pluripotency by promoting E-cadherin-mediated cell–cell interaction and Wnt signaling. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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23. Estimation on Reliability Models of Bearing Failure Data.
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Xintao, Xia, Zhen, Chang, Lijun, Zhang, and Xiaowei, Yang
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BEARINGS (Machinery) , *STATISTICAL reliability , *WEIBULL distribution , *ESTIMATION theory , *COMPUTER simulation , *ERROR analysis in mathematics - Abstract
The failure data of bearing products is random and discrete and shows evident uncertainty. Is it accurate and reliable to use Weibull distribution to represent the failure model of product? The Weibull distribution, log-normal distribution, and an improved maximum entropy probability distribution were compared and analyzed to find an optimum and precise reliability analysis model. By utilizing computer simulation technology and k-s hypothesis testing, the feasibility of three models was verified, and the reliability of different models obtained via practical bearing failure data was compared and analyzed. The research indicates that the reliability model of two-parameter Weibull distribution does not apply to all situations, and sometimes, two-parameter log-normal distribution model is more precise and feasible; compared to three-parameter log-normal distribution model, the three-parameter Weibull distribution manifests better accuracy but still does not apply to all cases, while the novel proposed model of improved maximum entropy probability distribution fits not only all kinds of known distributions but also poor information issues with unknown probability distribution, prior information, or trends, so it is an ideal reliability analysis model with least error at present. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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24. An economy-ralated equity analysis of health service utilization by women in economically underdeveloped regions of western China.
- Author
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Yuyan Qian, Zhongliang Zhou, Ju'e Yan, Jianmin Gao, Yuping Wang, Xiaowei Yang, Yongjian Xu, and Yanli Li
- Subjects
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AGE distribution , *HEALTH services accessibility , *HEALTH status indicators , *HEALTH insurance , *MARITAL status , *MEDICAL care use , *METROPOLITAN areas , *REGRESSION analysis , *RURAL conditions , *SELF-evaluation , *WOMEN'S health , *SOCIOECONOMIC factors , *EDUCATIONAL attainment - Abstract
Background: The Chinese government has long been committed to eliminating the inequality in the utilization of health services; however, it still lacks an analysis or measurement of the economy-related inequality in the utilization of women's health services. Methods: The economy-related utilization of health services in women aged 15 years and above was assessed by the horizontal inequity index of a two-week outpatient rate and annual inpatient rate from the 5th National Health Service Survey of Shaanxi Province. The concentration index of each factor was decomposed into the contribution of each factor to the economic-related inequality of health service utilization based on the Probit regression model. Results: The horizontal inequity indexes of the two-week outpatient rate was 0.0493, and the horizontal inequity indexes of the annual impatient rate was 0.0869. The contributions of economic status to the two indexes were 190. 71% and 115.80%, respectively. Economic status, age, basic medical insurance, educational status, marital status, urban/rural area, and self-rated health were the main impact factors that affected the inequality in women's health services utilization in Shaanxi. Conclusions: Health service utilization was different between women with different social demographic characteristics, and unequal health service utilization is evident among women in Shaanxi. [ABSTRACT FROM AUTHOR]
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- 2017
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25. The draft genome of whitefly Bemisia tabaci MEAM1, a global crop pest, provides novel insights into virus transmission, host adaptation, and insecticide resistance.
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Wenbo Chen, Hasegawa, Daniel K., Kaur, Navneet, Kliot, Adi, Pinheiro, Patricia Valle, Junbo Luan, Stensmyr, Marcus C., Yi Zheng, Wenli Liu, Honghe Sun, Yimin Xu, Yuan Luo, Kruse, Angela, Xiaowei Yang, Kontsedalov, Svetlana, Lebedev, Galina, Fisher, Tonja W., Nelson, David R., Hunter, Wayne B., and Brown, Judith K.
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SWEETPOTATO whitefly , *INSECTICIDE resistance , *INTRODUCED species , *FOOD security , *GLUCURONOSYLTRANSFERASE - Abstract
Background: The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is among the 100 worst invasive species in the world. As one of the most important crop pests and virus vectors, B. tabaci causes substantial crop losses and poses a serious threat to global food security. Results: We report the 615-Mb high-quality genome sequence of B. tabaci Middle East-Asia Minor 1 (MEAM1), the first genome sequence in the Aleyrodidae family, which contains 15,664 protein-coding genes. The B. tabaci genome is highly divergent from other sequenced hemipteran genomes, sharing no detectable synteny. A number of known detoxification gene families, including cytochrome P450s and UDP-glucuronosyltransferases, are significantly expanded in B. tabaci. Other expanded gene families, including cathepsins, large clusters of tandemly duplicated B. tabaci-specific genes, and phosphatidylethanolamine-binding proteins (PEBPs), were found to be associated with virus acquisition and transmission and/or insecticide resistance, likely contributing to the global invasiveness and efficient virus transmission capacity of B. tabaci. The presence of 142 horizontally transferred genes from bacteria or fungi in the B. tabaci genome, including genes encoding hopanoid/sterol synthesis and xenobiotic detoxification enzymes that are not present in other insects, offers novel insights into the unique biological adaptations of this insect such as polyphagy and insecticide resistance. Interestingly, two adjacent bacterial pantothenate biosynthesis genes, panB and panC, have been co-transferred into B. tabaci and fused into a single gene that has acquired introns during its evolution. Conclusions: The B. tabaci genome contains numerous genetic novelties, including expansions in gene families associated with insecticide resistance, detoxification and virus transmission, as well as numerous horizontally transferred genes from bacteria and fungi. We believe these novelties likely have shaped B. tabaci as a highly invasive polyphagous crop pest and efficient vector of plant viruses. The genome serves as a reference for resolving the B. tabaci cryptic species complex, understanding fundamental biological novelties, and providing valuable genetic information to assist the development of novel strategies for controlling whiteflies and the viruses they transmit. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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26. Clenbuterol Distribution and Residues in Goat Tissues After the Repeated Administration of a Growth-Promoting Dose.
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Zhen Zhao, Ting Yao, Yuchang Qin, Xiaowei Yang, Jun Li, Junguo Li, and Xu Gu
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CLENBUTEROL , *TISSUE analysis , *DRUG residues in the body , *ORGANIC solvents , *GOATS as laboratory animals , *LIQUID chromatography-mass spectrometry - Abstract
This study was conducted to investigate the deposition and depletion process of clenbuterol (CL) in goat tissues, plasma and urine after the repeated administration of a growth-promoting dose. The experiment was conducted in 24 goats (21 treated and 3 controls). Treated animals were administered orally in a dose of 16 µg/kg body mass once daily for 21 consecutive days and randomly sacrificed on days 0.25, 1, 3, 7, 14, 21 and 28 of the withdrawal period. CL in goat tissues was extracted with organic solvents and determined using liquid chromatography tandem mass spectrometry. The depletion rates of tissue differed significantly. The highest concentrations of CL in all tissues are detected on day 0.25 of treatment discontinuation. After administration had been discontinued for 28 days, CL still residues in all tissues, especially, in whole eye, where the concentrations reach 363.29 ± 31.60 µg/kg. These findings confirmed that the whole eye, which are rich in pigment, showed a much higher concentration than any other studied tissue during the withdrawal period. [ABSTRACT FROM AUTHOR]
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- 2015
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27. Vertically Aligned Carbon Nanotubes on Carbon Nanofibers:A Hierarchical Three-Dimensional Carbon Nanostructure for High-EnergyFlexible Supercapacitors.
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Yongcai Qiu, Guizhu Li, Yuan Hou, Zhenghui Pan, Hongfei Li, Wanfei Li, Meinan Liu, Fangmin Ye, Xiaowei Yang, and Yuegang Zhang
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CARBON nanotubes , *SUPERCAPACITORS , *NANOSTRUCTURED materials , *NANOFIBERS , *ELECTRIC conductivity - Abstract
Hierarchicalstructures enable high-performance power sources.We report here the preparation of vertically aligned carbon nanotubesdirectly grown on carbon nanofibers (VACNTs/CNFs) by combining electrospinningwith pyrolysis technologies. The structure and morphology of VACNTs/CNFscould be precisely tuned and controlled by adjusting the percentageof reactants. The desired VACNTs/CNFs could not only possess highelectric conductivity for efficient charge transport but could alsoincrease surface area for accessing more electrolyte ions. When usingan ionic liquid electrolyte, VACNTs/CNFs-based electric double layer(EDL) flexible supercapacitors can deliver a high specific energyof 70.7 Wh/kg at a current density of 0.5 A/g and at 30 °C, andan ultrahigh-energy density of 98.8 Wh/kg at a current density of1.0 A/g and at 60 °C. Even after 20 000 charging/dischargingcycles, the EDL capacitor still retains 97.0% of the initial capacitance.The excellent performance highlights the important role of the branchedVACNTs in storing and accumulating charge and the CNF backbone intransporting charge, thereby boosting both power density and energydensity. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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28. An association of Aquaporin-4 with the immunoregulation of liver pathology in mice infected with Schistosoma japonicum.
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Weiwei Zhang, Jifeng Zhu, Xian Song, Zhipeng Xu, Xue Xue, Xiaojun Chen, Xiaowei Yang, Yong Li, Xiaoxiao Dong, Sha Zhou, Wei Li, Yingying Qian, Feng Liu, and Chuan Su
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AQUAPORINS , *SCHISTOSOMA japonicum , *GRANULOMA , *IMMUNOREGULATION , *SCHISTOSOMIASIS - Abstract
Background Schistosomiasis is a chronic parasitic disease that affects approximately 200 million people. In Schistosomiasis japonica and mansoni, parasite eggs were trapped in host liver and stimulated the CD4+T cell responses to regulate the formation of the granulomas. Subsequently, excessive granulomatous response in some heavily, and/or repeatedly infected individuals could result in chronic liver fibrosis and circulatory impairment. Thus, elucidation of the mechanisms of these responses will not only provide more information to better understand the mechanisms of the immunoregulation in schistosomiasis, but also help to design new therapies to control granuloma-associated immunopathology. The role of aquaporin-4 (AQP4) in water transport has been extensively investigated in the central nervous system (CNS). Recently, studies have shown that AQP4 expresses in immune system and lack of AQP4 in mice results in significantly less CD4+CD25+ T regulatory cells (Treg cells) under physiological condition, one of the subpopulations of CD4+T cells which restrains immunopathology in hosts with schistosomiasis. However, little information exists regarding the contribution of AQP4 to the immune regulation in schistosome infection. Methods The liver granulomatous response in S. japonicum-infected AQP4 knockout (KO) mice and its wild-type (WT) littermates were detected by staining liver sections with hematoxylin and eosin. The generation of various CD4+ T subsets, including Th1, Th2, Th17, and Treg cells were analyzed by flow cytometry. In addition, the levels of total IgG, IgG1, IgG2a in serum of infected mice were detected by ELISA assay. Results Our results showed an enhanced granulomatous response with increased accumulation of eosinophils and macrophages around eggs in the liver of AQP4 KO mice with Schistosomiasis japonica. In addition, our study demonstrated enhanced Th2 but reduced Th1 and Treg cells generation in AQP4 KO mice with Schistosomiasis japonica, which may, at least partly, account for the enhancement of the liver granuloma formation. Conclusion Our study for the first time provides evidences that AQP4 has an association with the immunoregulation of the liver granuloma formation, which may confer a new option for schistosomiasis treatment. [ABSTRACT FROM AUTHOR]
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- 2015
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29. Integrative Bayesian variable selection with genebased informative priors for genome-wide association studies.
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Xiaoshuai Zhang, Fuzhong Xue, Hong Liu, Dianwen Zhu, Bin Peng, Wiemels, Joseph L., and Xiaowei Yang
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PHENOTYPES , *SINGLE nucleotide polymorphisms , *HERITABILITY , *HANSEN'S disease , *BIOMARKERS , *BAYESIAN analysis - Abstract
Background: Genome-wide Association Studies (GWAS) are typically designed to identify phenotypeassociated single nucleotide polymorphisms (SNPs) individually using univariate analysis methods. Though providing valuable insights into genetic risks of common diseases, the genetic variants identified by GWAS generally account for only a small proportion of the total heritability for complex diseases. To solve this "missing heritability" problem, we implemented a strategy called integrative Bayesian Variable Selection (iBVS), which is based on a hierarchical model that incorporates an informative prior by considering the gene interrelationship as a network. It was applied here to both simulated and real data sets. Results: Simulation studies indicated that the iBVS method was advantageous in its performance with highest AUC in both variable selection and outcome prediction, when compared to Stepwise and LASSO based strategies. In an analysis of a leprosy case-control study, iBVS selected 94 SNPs as predictors, while LASSO selected 100 SNPs. The Stepwise regression yielded a more parsimonious model with only 3 SNPs. The prediction results demonstrated that the iBVS method had comparable performance with that of LASSO, but better than Stepwise strategies. Conclusions: The proposed iBVS strategy is a novel and valid method for Genome-wide Association Studies, with the additional advantage in that it produces more interpretable posterior probabilities for each variable unlike LASSO and other penalized regression methods. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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30. A GA-based feature selection and parameter optimization for linear support higher-order tensor machine.
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Tengjiao Guo, Le Han, Lifang He, and Xiaowei Yang
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PROCESS optimization , *LINEAR statistical models , *MACHINE learning , *COMPUTER vision , *IMAGE processing , *DATA analysis , *GENETIC algorithms - Abstract
In the fields of pattern recognition, computer vision, and image processing, many real-world image and video data are more naturally represented as tensors. Recently, based on the supervised tensor learning (STL) framework, a linear support higher-order tensor machine (SHTM) has been proposed. Considering that there are much redundancy information in the tensor data and the model parameter largely affects the performance of SHTM, in this study, we present a genetic algorithm (GA) based feature selection and parameter optimization algorithm for the linear SHTM. The proposed algorithm can remove the redundancy information in tensor data and obtain a better generalized accuracy by searching for the optimal model parameter and feature subset simultaneously. A set of experiments is conducted on nine second-order face recognition datasets and three third-order gait recognition datasets to illustrate the performance of the proposed algorithm. The statistic test shows that compared with the original linear SHTM, the proposed algorithm can provide a significant performance gain in terms of generalized accuracy for tensor classification. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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31. Association between Leukocyte and Metabolic Syndrome in Urban Han Chinese: A Longitudinal Cohort Study.
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Wenjia Meng, Chengqi Zhang, Qian Zhang, Xinhong Song, Haiyan Lin, Dongzhi Zhang, Yongyuan Zhang, Zhenxin Zhu, Shuo Wu, Yanxun Liu, Fang Tang, Xiaowei Yang, and Fuzhong Xue
- Subjects
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NUCLEOTIDE sequence , *METAGENOMICS , *IMMUNITY , *RIBOSOMAL RNA , *GENES , *BACTERIAL genetics - Abstract
Background: Although cross-sectional studies have shown that leukocyte is linked with metabolic syndrome (MetS), few longitudinal or cohort studies have been used to confirm this relationship. We therefore conducted a large-scale health check-up longitudinal cohort in urban Chinese population from middle to upper socioeconomic strata to investigate and prove the association between the total leukocyte/its subtypes and MetS/its components (obesity, hyperglycemia, dyslipidemia, and hypertension). Methods: A longitudinal cohort study was established in 2005 on individuals who were middle-to-upper class urban Chinese. Data used in this investigation was based on 6,513 participants who had at least three routine health check-ups over a period of six-year follow-up. Data analysis was conducted through generalized estimating equation (GEE) model. Results: A total of 255 cases of MetS occurred over the six-year follow-up, leading to a total incidence density of 11.45 per 1,000 person-years (255/22279 person-years). The total leukocyte was markedly associated with MetS (RR = 2.66, 95%CI = 1.81-3.90], p<0.0001) and a dose-response existed. Similar trends can be found in monocytes, lymphocytes, and neutrophils compared with the total leukocyte. The total leukocyte, neutrophil, monocyte and eosinophil levels were strong and independent risk factors to obesity, total leukocyte and neutrophil to dyslipidemia and hyperglycemia, while neither total leukocyte nor its subtypes to hypertension. Conclusion: Total leukocyte/its subtype were associated with MetS/its components (obesity, dyslipidemia and hyperglycemia), they might provide convenient and useful markers for further risk appraisal of MetS, and be the earlier biomarkers for predicting cardiovascular disease than the components of MetS. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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32. A longitudinal cohort based association study between uric acid level and metabolic syndrome in Chinese Han urban male population.
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Qian Zhang, Chengqi Zhang, Xinhong Song, Haiyan Lin, Dongzhi Zhang, Wenjia Meng, Yongyuan Zhang, Zhenxin Zhu, Fang Tang, Longjian Liu, Xiaowei Yang, and Fuzhong Xue
- Subjects
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URIC acid , *ALLOXAN , *COHORT analysis , *METABOLIC syndrome , *CITY dwellers , *DISEASES in men - Abstract
Background: It has been recently demonstrated that serum uric acid (UA) is associated with metabolic syndrome (MetS) or its related clinical indications based on cross-sectional or prospective cohort studies. Nonetheless, due to the fact that UA level constantly fluctuates from time to time even for the person, using a single measure of UA level at baseline of those studies may not be sufficient for estimating the UA-Mets association. Methods: To further estimate this time-dependent association, we fitted a generalized estimating equation (GEE) regression model with data from a large-scale 6-year longitudinal study, which included 2222 participants aged>=25 years with an average of 3.5 repeated measures of UA per person in the Health Management Center of Shandong Provincial Hospital, Shandong, China. Results: After adjusting for other potential confounding factors (i.e., total cholesterol, low-density lipoprotein), it was verified that time-dependent UA level was an independent risk factor for MetS (OR = 1.6920, p<0.0001). It was found that UA level was positively associated with obesity, hypertension, and dyslipidemia, but was inversely associated with hyperglycemia. Conclusions: Serum UA level may serve as an important risk factor of MetS. Additionally, our study suggested that UA level be an independent risk factor to obesity, hypertension and dyslipidemia, but a protective factor to hyperglycemia. These findings are concordant with results from other studies on Asian populations, and jointly provide a basis to further develop a risk assessment model for predicting MetS using UA levels and other factors in China. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
33. Synthesis of nanocomposite nickel oxide/yttrium-stabilized zirconia (NiO/YSZ) powders for anodes of solid oxide fuel cells (SOFCs) via microwave-assisted complex-gel auto-combustion
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Tongxiang, Cai, Yanwei, Zeng, Wei, Zhang, Cuijing, Guo, and Xiaowei, Yang
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NANOCOMPOSITE materials , *METAL powders , *SOLID oxide fuel cells , *NICKEL compounds , *YTTRIUM , *ZIRCONIUM oxide - Abstract
Abstract: Nanocomposite NiO/YSZ powders for high performance anodes of SOFCs have been synthesized via a microwave-assisted complex-gel auto-combustion approach using nitrates of Ni2+, Zr4+ and Y3+, citric acid (CA) and ethyl glycol as starting materials. The complexing conditions including pH and molar ratio of CA to the metal ions in the aqueous solutions have been quantitatively analyzed and optimized to realize their complete chelating into the CA-based gel network. The processing features and the microstructural characteristics of NiO/YSZ phases formed during auto-combustion of gels have been investigated by FT-IR, TG-DSC, XRD, SEM, SAED and HRTEM. It has been found that the nanoscale composite powders of NiO/YSZ, directly obtained through the in situ auto-combustion reactions within the gels, are composed of loosely agglomerated particles with sizes of ∼200nm, while these particles themselves are the aggregates of finer NiO and YSZ crystallites of ∼15nm in size. Moreover, the anodes prepared with such nanoscale composite powders have been manifested to possess much better electrochemical properties than the ones obtained by normal NiO/YSZ powder (∼2.5μm) according to their measurements of AC impedance and temperature programmed reduction behavior due to the highly enhanced three-dimensional transport network of oxide ions and triple-phase boundaries for surface reactions. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
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34. One-step synthesis of barium hexaferrite nano-powders via microwave-assisted sol–gel auto-combustion
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Junliang, Liu, Yanwei, Zeng, Cuijing, Guo, Wei, Zhang, and Xiaowei, Yang
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BARIUM compounds , *CITRIC acid , *ETHYLENEDIAMINE , *METAL ions , *OXIDIZING agents , *COMBUSTION , *MAGNETIC properties , *FERRITES , *MAGNETIZATION - Abstract
Abstract: Single phase barium hexaferrite nano-powders have been innovatively one-step synthesized via a microwave-assisted sol–gel auto-combustion in a specially designed quartz vessel using citric acid and ethylene diamine tetraacetic acid as composite chelating agents and freeze-drying technique to remove sols’ moisture. The auto-combustion product powder is characterized by fluffy particle aggregates with the crystallites ranging from 50 to 100nm in diameter and containing single magnetic domains for each with a low apparent coercive field of 260Oe and a high saturation magnetization of 64.1emu/g. The direct formation of barium hexaferrite is believed to result from the effective improvement in the spatial distribution homogeneity of metal ions and oxidant in the gels. Moreover, the quartz vessel with barium hexaferrite ceramic pad on sample''s support and film-strips on its interior wall can effectively build up a favorable temperature environment to promote the direct formation of barium hexaferrite with microwave assistance during the gel''s uniform auto-combustion. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
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35. Mental Health Problems and Service Use Among Female Juvenile Offenders: Their Relationship to Criminal History.
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Kataoka, Sheryl H., Zima, Bonnie T., Dupre, Deirdre A., Moreno, Kathleen A., Xiaowei Yang, and McCracken, James T.
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WOMEN criminals , *FEMALE juvenile offenders , *MENTAL health services , *MENTAL health - Abstract
Discusses a study that described the level of mental health problems and lifetime mental health services use among incarcerated female juvenile offenders in Los Angeles County, California. Sample characteristics and level of mental health problems; Problems attributed to substance use among incarcerated female juvenile offenders; Relationship between mental health problems and service use with criminal history.
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- 2001
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36. Behavior Problems, Academic Skill Delays and School Failure Among School-Aged Children in Foster Care: Their Relationship to Placement Characteristics.
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Zima, Bonnie T., Bussing, Regina, Freeman, Stephanny, Xiaowei Yang, Belin, Thomas R., and Forness, Steven R.
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FOSTER home care , *SCHOOL children , *INTERVIEWING , *MENTAL health , *EDUCATION , *SOCIODEMOGRAPHIC factors - Abstract
We describe the level of behavior problems, academic skill delays, and school failure among school-aged children in foster care. We also examine how behavior problems are associated with academic problems, and explore how these outcomes are related to children's placement characteristics. Foster parent and child home interviews, as well as teacher telephone interviews were conducted from a randomly selected sample of 302 children aged 6 through 12 years living in out-of-home placement. Interviews included standardized screening measures. Results showed that 27% of the children scored in the clinical range for a behavior problem, and 34% were rated as having at least one behavior problem in the classroom. Twenty-three percent of the children had severe delays in reading or math, 13% had repeated a grade, and 14% had a history of school suspension and/or expulsion. Behavior problems by foster parent report were related to child suspension and/or expulsion from school, but were not associated with severe academic delays or grade retention. Placement characteristics were only sometimes related to these outcomes. Future studies examining the mental health and educational needs of this population should take into account the child's sociodemographic and placement characteristics. [ABSTRACT FROM AUTHOR]
- Published
- 2000
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- View/download PDF
37. The 1.8kb DNA fragment formerly confirmed as Mycoplasma suis (M. suis) specific was originated from the porcine genome
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Congli, Yuan, Zhibiao, Yang, Ningyu, Zhu, Congbin, Yao, Xiaowei, Yang, Jianguo, Zhu, Li, Cui, and Xiuguo, Hua
- Published
- 2009
- Full Text
- View/download PDF
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