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Role of trichome of Pteris vittata *** arsenic hyperaccu-mulation

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Science China(life Sciences) 2005年第2期48卷 148-154页

作者： li wenxue CHEN Tongbin CHEN Yang LEI Mei Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Environmental scanning electron microscope(ESEM)fitted with an energy disper-sive X-ray microanalyzer(EDX)was used to investigate the surface micromorphology and arse-nic(As)micro-distribution in Chinese brake(Pteris vittata L.).It was found that amounts of trichome,which possessed multicellular structure with the average length of 160μm and with an average diameter of 28μm,existed in the frond of ***,and the density of trichome on the pinnate axial surface was higher than that on the *** X-ray peak of As was recorded in the epidermal cell and *** relative weight of As in the pinnate trichome,which con-tained the highest concentration of As among all tissues of the plant,was 2.4 and 3.9 times as much as that in the epidermal and mesophyllous cells,*** As concentrations in the basal and stalk cells of the same trichome were higher than that in its cap *** is the first time to report that the trichome of *** plays an important role in arsenic *** finding from the present study implies that much attention should be paid to the role of the trichome in understanding the hyperaccumulation and detoxicity of As in the hyperaccumulator and improving the ability of As accumulation.

关键词： arsenic environmental scanning electron microscope(ESEM) hyperaccumulation micro-distribution Pteris vittata L. trichome.

Morphological structures of poly(vinylidene fluoride)/montmorillonite nanocomposites

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Science China Chemistry 2007年第6期50卷 790-796页

作者： SONG YuMing ZHAO ZhuDi YU wenxue li Bo CHEN XinFang College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China

Poly(vinylidene fluoride)(PVDF)/montmorillonite(MMT)nanocomposites were prepared by melt blending a kind of organically modified montmorillonite with *** morphological structures of the nanocomposites were studied using X-ray diffraction(XRD),transmission electron microscopy(TEM),Fourier transform infrared(FTIR)spectroscopy,and differential scanning calorimetry(DSC).The results indicate that organically modified montmorillonites are in the form of intercalation,exfoliation,and fragments in the PVDF *** the composites,the(001)peak position of MMT was found to shift to a lower angle in XRD patterns,and some MMT fragments could be observed under *** loading was favorable to producing the piezoelectric beta phase in the PVDF matrix and caused internal stress in a *** the same time,the crystallinity and spherulite size of PVDF decreased with the MMT *** induced beta phase is stable even at high temperatures(160℃).For these changes in morphological structures,some possible explanations were proposed based on the experimental results.

关键词： organically modified montmorillonite, nanocomposite, crystalline structure

Are Chinese Acquirers Discriminated against in Cross-border Mergers and Acquisitions?An Analysis Based on Covered Transactions Filed with CFIUS

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China & World Economy 2020年第2期28卷 37-58页

作者： Sichong Chen wenxue li Qi Wang School of Finance and the Collaborative Innovation Center of Industrial Upgrading and Regional Finance(Hubei) Zhongnan University of Economics and Law China School of Finance Zhongnan University of Economics and LawChina.

This study employs a sample of covered transactions filed with the Committee on Foreign Investment in the United States(CFIUS)of cross-border mergers and acquisitions targeting American companies based on publicly available news reports and announcements to examine the heterogeneity hypothesis in the CFIUS review process.A comparative analysis of case studies and an empirical analysis of logit regressions are *** also explore how CFIUS reviews may have an impact on corporations'future mergers and acquisitions decisions in a panel data model *** results show that both unfair treatment in CFIUS review and the deterrent effect of CFIUS interventions have contributed to the recent sharp decline in China s direct investment in the US.

关键词： CFIUS covered transaction cross-border M&A deterrent effect fair treatment

Effect of Deposition Temperature on the Structure and Mechanical Properties of Ti-6Al-4V Film

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Effect of Deposition Temperature on the Structure and Mechan...

A basic phosphoproteomic-DIA workflow integrating precise quantification of phosphosites in systems biology

中国材料大会2012

作者： li Lei Lu Yafeng li wenxue Zeng liying Yang Yi Hou Zhimin Han Dong Northwest Institute for Nonferrous Metal Research The No.2 Process Department China Petroleum Pipeline Engineering Corporation

ISBN: (纸本)9783037856093;3037856092

Ti-6Al-4V films were deposited by direct-current magnetron sputtering at different substrate temperatures. The structure and the surface morphology of the films were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The hardness and elastic moduli of Ti-6Al-4V films were measured by nanoindentation test. The results showed that the phase direction of the films deposited at room temperature was （102） orientation, and turned to almost complete （002） preferred orientation at 300℃. For a higher temperature of 500℃, the preferred orientation of the film disappeared and presented a random grain orientation. The hardness and elastic moduli of Ti-6Al-4V films obviously showed the dependence on the temperature. The relationships among temperature, microstructure and mechanical properties of Ti-6Al-4V films were discussed in this paper.

关键词： Ti-6Al-4V films Microstructure Crystallographic orientation Mechanical properties.

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Biophysics Reports 2023年第2期9卷 82-98页

作者： Yi Di wenxue li Barbora Salovska Qian Ba Zhenyi Hu Shisheng Wang Yansheng liu Cancer Biology Institute Yale University School of Medicine Laboratory Center Shanghai Municipal Hospital of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine 3. Department of Pulmonary and Critical Care Medicine and Proteomics-Metabolomics Analysis Platform West China Hospital Sichuan University Department of Pharmacology Yale University School of Medicine

Phosphorylation is one of the most important post-translational modifications(PTMs) of proteins, governing critical protein functions. Most human proteins have been shown to undergo phosphorylation,and phosphoproteomic studies have been widely applied due to recent advancements in highresolution mass spectrometry technology. Although the experimental workflow for phosphoproteomics has been well-established, it would be useful to optimize and summarize a detailed, feasible protocol that combines phosphoproteomics and data-independent acquisition(DIA), along with follow-up data analysis procedures due to the recent instrumental and bioinformatic advances in measuring and understanding tens of thousands of site-specific phosphorylation events in a single experiment. Here,we describe an optimized Phos-DIA protocol, from sample preparation to bioinformatic analysis, along with practical considerations and experimental configurations for each step. The protocol is designed to be robust and applicable for both small-scale phosphoproteomic analysis and large-scale quantification of hundreds of samples for studies in systems biology and systems medicine.

关键词： Bioinformatic analysis High-resolution mass spectrometry technology Phosphoproteomics Systems biology Systems medicine

Dual-comb spectroscopy from the ultraviolet to mid-infrared region based on high-order harmonic generation

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Photonics Research 2023年第8期11卷 1373-1381页

作者： YUANFENG DI ZHONG ZUO DAOWANG PENG DAPING LUO CHENGliN GU wenxue li State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

Dual-comb spectroscopy(DCS)has revolutionized numerous spectroscopic applications due to its high spectral resolution and fast measurement *** efforts have been made to obtain a coherent dual-comb source at various spectral regions through nonlinear frequency conversion,where the preservation of coherence has become a problem of great *** this study,we report the generation of coherent dual-comb sources covering from the ultraviolet to mid-infrared region based on high-order harmonic *** by high-repetition-rate femtosecond mid-infrared dual-comb pump pulses,up to ninth-order harmonic was generated from the ultraviolet to mid-infrared region using an aperiodically poled lithium niobate *** investigate the coherence property of the high-order harmonic generation,DCS was performed at every generated spectral region from 450 to 3600 *** measured dual-comb spectra with distinctive tooth-resolved structures show the well-preserved coherence without apparent degradation after the cascaded quadratic nonlinear *** subsequent methane absorption spectroscopy at multiple spectral regions of different harmonics was carried out to characterize the spectroscopic capability of the *** results demonstrate the potential of our scheme to generate compact and coherent broadband optical frequency combs for simultaneous multi-target detections.

关键词： pump harmonic ultraviolet

Zea mays(L.) P1 locus for cob glume color identified as a post-domestication selection target with an effect on temperate maize genomes

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The Crop Journal 2013年第1期1卷 15-24页

作者： Chuanxiao Xie Jianfeng Weng Wenguo liu Cheng Zou Zhuanfang Hao wenxue li Minshun li Xiaosen Guo Gengyun Zhang Yunbi Xu Xinhai li Shihuang Zhang Institute of Crop Science Chinese Academy of Agricultural SciencesThe National Key Facility for Crop Gene Resources and Genetic Improvement Maize Research Institute Jilin Academy of Agricultural Sciences BGI-Shenzhen Chinese Ministry of Agriculture Key Laboratory of Genomics International Maize and Wheat Improvement Center (CIMMYT) Mexico D. F. 06600 Mexico

Artificial selection during domestication and post-domestication improvement results in loss of genetic diversity near target loci. However, the genetic locus associated with cob glume color and the nature of the genomic pattern surrounding it was elusive and the selection effect in that region was not clear. An association mapping panel consisting of 283 diverse modern temperate maize elite lines was genotyped by a chip containing over 55,000 evenly distributed SNPs. Ten-fold resequencing at the target region on 40 of the panel lines and 47 tropical lines was also undertaken. A genome-wide association study(GWAS) for cob glume color confirmed the P1 locus, which is located on the short arm of chromosome 1, with a-log10 P value for surrounding SNPs higher than the Bonferroni threshold(α/n, α linear model(MLM) was implemented. A total of 26 markers were identified in a 0.78 Mb region surrounding the P1 locus, including 0.73 Mb and 0.05 Mb upstream and downstream of the P1 gene, respectively. A clear linkage disequilibrium(LD) block was found and LD decayed very rapidly with increasing physical distance surrounding the P1 locus. The estimates of π and Tajima's D were significantly(P lines at much finer resolution by resequencing(180-fold finer than chip SNPs), a more structured LD block pattern was found among the 40 resequenced temperate lines. All evidence indicates that the P1 locus in temperate maize has not undergone neutral evolution but has been subjected to artificial selection during post-domestication selection or improvement. The information and analytical results generated in this study provide insights as to how breeding efforts have affected genome evolution in crop plants.

关键词： Genome-wide association study Artificial selection linkage disequilibrium Crop genome evolution

Frequency comb generation from the ultraviolet to mid-infrared region based on a three-stage cascaded PPLN chain

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Photonics Research 2024年第9期12卷 2012-2017页

作者： XIONG QIN DAPING LUO liAN ZHOU JIAYI PAN ZEJIANG DENG GEHUI XIE CHENGliN GU wenxue li State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

Optical frequency combs(OFCs)have enabled significant opportunities for high-precision frequency metrology and high-resolution broadband *** nonlinear photonics chips have the capacity of frequency expansion for OFCs,most of them can only access the limited bandwidths in the partial infrared region,and it is still hard to satisfy many measurement applications in the ultraviolet-to-visible ***,we demonstrate a compact broadband OFC scheme via the combination of three χ(2) nonlinearities in a three-stage periodically poled lithium niobate(PPLN)*** a supercontinuum spectrum OFC delivered into the PPLN chain,the intra-pulse diffidence frequency generation,optical parametric amplification,and high-order harmonic generation were carried out in *** is crucial that the harmonics of the 1st–10th orders are simultaneously obtained with an offset-free OFC spectrum from 0.35 to 4.0μ*** view of the great potential for integration and spectral expansion,this wideband frequency comb source will open a new insight for the valuable applications of two-dimensional material analysis,biofluorescence microscopy,and nonlinear amplitude-phase metrology.

关键词： ultraviolet metrology expansion

Nutrition strategies to control post-weaning diarrhea of piglets: From the perspective of feeds

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Animal Nutrition 2024年第2期17卷 297-311页

作者： Qingsong Tang Tianyi Lan Chengyu Zhou Jingchun Gao liuting Wu Haiyang Wei wenxue li Zhiru Tang Wenjie Tang Hui Diao Yetong Xu Xie Peng Jiaman Pang Xuan Zhao Zhihong Sun Laboratory for Bio-Feed and Molecular Nutrition College of Animal Science and Technology Southwest University Animal Breeding and Genetics Key Laboratory of Sichuan Province Sichuan Animal Science Academy Yibin Academy of Southwest University

Post-weaning diarrhea(PWD) is a globally significant threat to the swine industry. Historically, antibiotics as well as high doses of zinc oxide and copper sulfate have been commonly used to control ***, the development of bacterial resistance and environmental pollution have created an interest in alternative strategies. In recent years, the research surrounding these alternative strategies and the mechanisms of piglet diarrhea has been continually updated. Mechanically, diarrhea in piglets is a result of an imbalance in intestinal fluid and electrolyte absorption and secretion. In general, enterotoxigenic Escherichia coli(ETEC) and diarrheal viruses are known to cause an imbalance in the absorption and secretion of intestinal fluids and electrolytes in piglets, resulting in diarrhea when Cl secretion-driven fluid secretion surpasses absorptive capacity. From a perspective of feedstuffs, factors that contribute to imbalances in fluid absorption and secretion in the intestines of weaned piglets include high levels of crude protein(CP), stimulation by certain antigenic proteins, high acid-binding capacity(ABC), and contamination with deoxynivalenol(DON) in the diet. In response, efforts to reduce CP levels in diets,select feedstuffs with lower ABC values, and process feedstuffs using physical, chemical, and biological approaches are important strategies for alleviating PWD in piglets. Additionally, the diet supplementation with additives such as vitamins and natural products can also play a role in reducing the diarrhea incidence in weaned piglets. Here, we examine the mechanisms of absorption and secretion of intestinal fluids and electrolytes in piglets, summarize nutritional strategies to control PWD in piglets from the perspective of feeds, and provide new insights towards future research directions.

关键词： Post-weaning diarrhea Fluid secretion Feed Nutritional regulation strategies Piglet