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Rare Metals 2009年第2期28卷 117-121页

作者： zhao, Yujuan wang, Suijun zhao, Chunsong xia, Dingguo College of Environmental and Energy Engineering Beijing University of Technology Beijing 100124 China

LiCoPO4 micron-rods with an average diameter of about 500 nm and length of about 5 μm were synthesized by dispersant-aided hydrothermal method. Poly(n-vinylpyrrolidone) (PVP) was used as dispersant in the hydrothermal method. The starting solution and the concentration of dispersant have significant influences on the morphology of LiCoPO4,and the electrochemical performance is improved via controlling the particle size and morphology by the hydrothermal method. The cell using smaller particle LiCoPO4 as cat...

关键词： lithium cobalt phosphate hydrothermal method dispersant morphology

Cloning and Sequencing of a Full-Length cDNA Encoding the RuBPCase Small Subunit (RbcS) in Tea (Camellia sinensis)

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Agricultural Sciences in China 2009年第2期8卷 161-166页

作者： YE Ai-hua JIANG Chang-jun ZHU Lin YU Mei wang zhao-xia DENG Wei-wei WEI Chao-lin Key Laboratory of Tea Biochemistry and Biotechnology Ministry of Agriculture/Anhui Agricultural University Hefei 230036 P.R.China Department of Biology Hefei Teachers College Hefei 230061 P.R.China

This study was aimed to isolate ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit （RbcS） from tea plant [Camellia sinensis （L.） O. Kuntze]. In the study of transcriptional profiling of gene expression from tea flower bud development stage by cDNA-AFLP （cDNA amplified fragment length polymorphism）, we have isolated some transcript-derived fragments （TDFs） occurring in both the young and mature flower bud. One of them showed a high degree of similarity to RbcS. Based on the fragment, the full length of RbcS with 769-bp （EF011075） cDNA was obtained via rapid amplification of cDNA ends （RACE）. It contained an open reading frame of 176 amino acids consisting of a chloroplast transit peptide with 52 amino acids and a mature protein of 124 amino acids. The amino acids sequence presented a high identity to those of other plant RbcS genes. It also contains three conserved domains and a protein kinase C phosphorylation site, one tyrosine kinase phosphorylation site and two N-myristoylation sites. Analysis by RT-PCR showed that the expression of RbcS in tea from high to low was leaf, young stem, young flower bud and mature flower bud, respectively. The isolation of the tea Rubisco small subunit gene establishes a good foundation for further study on the photosynthesis of tea plant.

关键词： RbcS tea full-length cDNA

Average Consensus in Directed Networks of Multi-agents with Uncertain Time-varying Delays

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自动化学报 2014年第11期40卷 2602-2608页

作者： wang zhao-xia DU Da-Jun FEI Min-Rui Shanghai Key Laboratoy of Power Station Automation Technology School of Mechatronic Engineering and Automation Shang-hai University Shanghai 200072 China School of Electrical Engineering and Automation Qilu University of Technology Jinan 250353. China

This paper investigates the average consensus problem in directed networks of multi-agent systems with uncertain time-varying delays. Fixed and switching topologies that are kept weakly connected and balanced are firstly analyzed. The original system is then transformed into a reduced dimension model. Based on Jensen's inequality and reciprocally convex approach, sufficient conditions for average consensus are further presented. Specially, a less conservative upper bound of time-varying communication delays is derived in comparison with the existing results. Numerical examples confirm the effectiveness of the proposed method.

关键词：多代理系统时变延迟平均网络拓扑结构充分条件通信延迟时间变化

Diagnosis and Management of Kearns-Sayre Syndrome Rely on Comprehensive Clinical Evaluation

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Chinese Medical Journal 2016年第20期129卷 2519-2520页

作者： Meng Yu Lei Yu zhao-xia wang Department of Neurology Peking University First HospitalBeijing 100034China Department of Radiology Peking University First HospitalBeijing 100034China

We appreciate the readers＇ interest and their comprehensive comments and advice about the article,[1] which mainly concerned details of the patients＇ *** this paper,we reported 19 Kearns-Sayre syndrome （KSS） patients whose diagnoses were in accordance with the current clinical diagnostic criteria of KSS,i.e.,the triad of progressive external ophthalmoplegia,pigmentary retinopathy,and onset before 20 years of age,plus at least one of the followings：heart block,cerebellar symptoms,or cerebrospinal fluid protein levels above 1000 mg/L.[2] The diagnostic criteria have been widely used.[3] Apart from clinical features,muscle pathology and molecular genetic analysis canplay a great role in the diagnostic workup.

关键词：评价研究色素性视网膜炎心脏传导阻滞眼肌麻痹慢性进行性外侧综合征

Effect of Fe(III) impurity on the electrochemical performance of LiFePO_4 prepared by hydrothermal process

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Science China(Technological Sciences) 2009年第1期52卷 264-268页

作者： OU XiuQin, XU Shengzhao, LIANG GuangChuan, wang Li & zhao xia Institute of Power Source & Ecomaterials Science, Hebei University of Technology, Tianjin 300130, China Institute of Power Source & Ecomaterials Science Hebei University of Technology Tianjin 300130 China

Lithium iron phosphate (LiFePO4) was synthesized from LiOH, FeSO4 and H3PO4 by a hydrothermal process at 180℃. The samples were characterized by X-ray diffraction, scanning electron microscopy and chemical analysis. Electrochemical performance of the samples was tested in terms of charge-discharge capacity and cycling behavior. The results indicated that Fe(III) impurity had obvi- ously effect on the electrochemical properties of LiFePO4, and the formation of Fe3+ was caused by the oxidation of Fe2+ in the dissolving and feeding processes accompanying the increase of pH value. It was found that the precipitation separation was effective in decreasing the content of Fe3+ in the solu- tion of FeSO4 and the sealed feeding was useful in preventing the conversion of Fe2+ to Fe3+. When the content of Fe3+ < 0.5 wt%, the hydrothermally synthesized LiFePO4 calcined at 750℃ with sucrose as carbon source exhibited an initial discharge capacity of 154.9 mAh·g-1 at the rate of 0.1 C (1 C = 150 mA·g-1) and the cycling retention rate could reach 98% after 50 cycles at room temperature.

关键词： hydrothermal synthesis lithium iron phosphate (LiFePO4) ferric

A Fourth-order Covergence Newton-type Method

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Chinese Quarterly Journal of Mathematics 2008年第4期23卷 589-593页

作者： wang xia zhao Ling-ling Department of Mathematic and Information Science Zhengzhou University of Light Industry Zhengzhou 450002 China

A fourth-order convergence method of solving roots for nonlinear equation, which is a variant of Newton＇s method given. Its convergence properties is proved. It is at least fourth-order convergence near simple roots and one order convergence near multiple roots. In the end, numerical tests are given and compared with other known Newton and Newton-type methods. The results show that the proposed method has some more advantages than others. It enriches the methods to find the roots of non-linear equations and it is important in both theory and application.

关键词： Newton iteration method root-finding method fourth-order convergence numerical test

Optical coherence tomography findings in chronic progressive external ophthalmoplegia

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Chinese Medical Journal 2019年第10期132卷 1202-1207页

作者： Yuan Wu Lei Kang Hai-Long Wu Yue Hou zhao-xia wang Department of Ophthalmology Peking University First Hospital Beijing 100034 China Department of Neurology Peking University First Hospital Beijing 100034 China

Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial encephalomyopathy caused by multiple mtDNA abnormalities. There is little information about the changes of ocular fundus with CPEO. The aim of this work was to measure and evaluate changes in the macular retinal thickness and optic nerve head in patients with CPEO using spectral-domain optical coherence tomography and to compare the findings with those of healthy individuals. Methods: Totally, 18 CPEO patients were enrolled in this study. Healthy volunteers matched for gender, age, and diopter settings were included as a control group. The retinal thickness of macular central fovea, inner and outer retinal layer thickness of perifoveal macular, optic nerve head parameters, and peripapillay retinal nerve fiber layer thickness (pRNFLT) for all included cases were measured using spectral-domain optical coherence tomography. A paired t test was used to compare the differences in the studied parameters between the two groups. The correlations between macular retinal thickness, pRNFLT, disease duration, and age of onset were also analyzed. Results: Among the macular parameters, retinal thickness of macular central fovea (t=—2.135, P < 0.05) and outer retinal layer thickness (t =—1.994, P < 0.05) of patients in the CPEO group were statistically significant lower than those of patients in the normal control group. For the optic nerve head parameters, the patients in the CPEO group showed a larger rim volume (t =—2.499, P < 0.05) and nerve head volume (t =—2.103, P < 0.05). The overall pRNFLT of patients in the CPEO group was statistically significant lower than that of patients in the control group (t =—4.125, P < 0.05). The comparison of pRNFLT in eight sectors showed that the pRNFLT of patients in the CPEO group was statistically significant lower than that of the control group mainly in the inferior and temporal sectors. The degree of pRNFL defect negatively correlated with the disease dur

关键词： Optical coherence tomography Chronic progressive external ophthalmoplegia Retina Nerve fiber layer

Compound Heterozygote Mutation of C12orf65 Causes Distal Motor Neuropathy and Optic Atrophy

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Chinese Medical Journal 2017年第2期130卷 242-244页

作者： xiao-Jing Fang Wei Zhang He Lyu zhao-xia wang Wei-Wei wang Yun Yuan Department of Neurology Peking University First Hospital Beijing 100034 China

The C12orf65 gene is a nuclear gene that encodes a mitochondrial matrix protein contributing to mitochondrial translation. C12orf65 gene-related diseases are rare and present with large heterophenotypes. Most of the reported patients have had optic atrophy with intellectual disability, encephalomyopathy, spastic paraplegia, and ophthalmoplegia. Peripheral neuropathy has been reported in one thmily. Here, we report a case of a Chinese patient with optic atrophy and distal motor neuropathy due to a novel compound heterozygous mutation in the C12orf65 gene.

关键词： C12orf65 Protein Inherited Peripheral Neuropathy Optic Atrophy

Levetiracetam administration is correlated with lower mortality in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes: a retrospective study

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Chinese Medical Journal 2019年第3期132卷 269-274页

作者： Zhe Zhang Dan-Hua zhao Xu-Tong zhao xiao Zhang Hui Xiong Xin-Hua Bao Yun Yuan zhao-xia wang Department of Neurology Peking University First HospitalBeijing 100034China Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Department of Neurology Peking University International HospitalBeijing 102206China Department of Neurology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Pediatrics Peking University First HospitalBeijing 100034China

Background:Studies on the relationship between antiepileptic drug (AED) administration and clinical outcomes in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) remain scarce. Levetiracetam (LEV) is an AED that is neuroprotective in various neurologic disorders. This study aimed to determine the impact of LEV on the outcome of ***:A retrospective, single-center study was performed based on a large cohort of patients with MELAS with a history of seizures (n=102). Decisions on antiepileptic therapies were made empirically. Patients were followed up for 1 to 8 years (median, 4 years) and divided into 2 groups based on whether LEV was administered (LEV or non-LEV). The modified Rankin scale (mRS) scores and mortality risks were analyzed in all ***:LEV, carbamazepine, benzodiazepines, topiramate, oxcarbazepine, valproate, and lamotrigine were administered in 48, 37, 18, 13, 11, 9, and 9 patients, singly or in combination, respectively. The mean mRS score of the LEV group (n=48) was lower than that of the non-LEV group (n=54;mean±standard deviation, 2.79±1.47 vs. 3.83±1.93, P=0.006) up to the end of the study. Nevertheless, there was no difference in the proportion of subjects without disability (mRS ranging 0-1) between the groups (P=0.37). The multivariate regressions revealed that LEV treatment was associated with lower mRS scores (odds ratio 0.32, 95% confidence interval [CI] 0.15-0.68, P=0.003) and mortality rates (hazard ratio 0.24, 95% CI 0.08-0.74, P=0.013). There was a significant difference in the Kaplan-Meier survival curves between the groups (χ^2=4.29, P=0.04).Conclusions:The LEV administration is associated with lower mortality in patients with MELAS in this retrospective study. Further laboratory research and prospective cohort studies are needed to confirm whether LEV has neuroprotective effects on patients with mitochondrial diseases.

关键词： Syndrome Seizures Epilepsy Anticonvulsants Levetiracetam Survival analysis

Dysferlin Gene Mutation Spectrum in a Large Cohort of Chinese Patients with Dysferlinopathy

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Chinese Medical Journal 2016年第19期129卷 2287-2293页

作者： Su-Qin Jin Meng Yu Wei Zhang He Lyu Yun Yuan zhao-xia wang Department of Neurology Peking University First Hospital Beijing 100034 China

Background：Dysferlinopathy is caused by mutations in the dysferlin （DYSF） ***,we described the genetic features of a large cohort of Chinese patients with this ***：Eighty-nine index patients were included in the *** gene analysis was performed by Sanger sequencing in 41 patients and targeted next generation sequencing （NGS） in 48 *** ligation-dependent probe amplification （MLPA） was performed to detect exon duplication/deletion in patients with only one pathogenic ***：Among the 89 index patients,79 patients were demonstrated to carry two disease-causing （73 cases） or possibly disease-causing mutations （6 cases）,including 26 patients with homozygous *** identified 105 different mutations,including 59 novel ***,in 13 patients in whom only one pathogenic mutation was initially found by Sanger sequencing or NGS,3 were further identified to carry exon deletions by *** mutations identified in this study appeared to cluster in the N-terminal *** types included missense mutations （30.06%）,nonsense mutations （1 7.18%）,frameshift mutations （30.67%）,in-frame deletions （2.45%）,intronic mutations （17.79%）,and exonic rearrangement （1.84%）.No genotype-phenotype correlation was ***：DYSF mutations in Chinese patients clustered in the N-terminal region of the *** rearrangements were found in 23% of patients with only one pathogenic mutation identified by Sanger sequencing or *** novel mutations found in this study greatly expanded the mutational spectrum of dysferlinopathy.

关键词： Dysferlin Gene Dysferlinopathy Exonic Rearrangements China's Mainland Novel Mutation