Polymer membrane fuel cells represent important sustainable energy devices because their operation involves zero emissions and low temperatures and their components exhibit low toxicity. Among the various components o...Polymer membrane fuel cells represent important sustainable energy devices because their operation involves zero emissions and low temperatures and their components exhibit low toxicity. Among the various components of such cells, the electrocatalyst plays the vital role of enhancing the output power density and/or working lifetime. Over the past several decades, numerous strategies have been proposed to address the challenges of electrocatalyst activity and/or durability. Herein, we review the applications of polyelectrolytes in electrocatalysts, including the enhancement of both catalytic nanoparticles and support materials. The effects of polyelectrolytes with regard to controlling the size, composition and morphology of catalytic nanoparticles, as well as the modification of support materials were summarized. In addition, the future possibilities for the research and development of polyelectrolytes in the field of catalyst design and synthesis are discussed.展开更多
Dy Ov sfunctional audit behaviour （DAB） and staff turnover are associated with decreased audit quality （Public ersight Board, 2000）. This study develops and tests a theoretical model that turnover intentions and l...Dy Ov sfunctional audit behaviour （DAB） and staff turnover are associated with decreased audit quality （Public ersight Board, 2000）. This study develops and tests a theoretical model that turnover intentions and locus of control as antecedents of attitudes toward DAB survey results from 225 auditors support the theoretical model identifies employee performance, Using a path analysis technique,展开更多
Adult stem cells(SCs) exist in all tissues that promote tissue growth, regeneration, and healing throughout life. The SC niche in which they reside provides signals that direct them to proliferate, differentiate, or r...Adult stem cells(SCs) exist in all tissues that promote tissue growth, regeneration, and healing throughout life. The SC niche in which they reside provides signals that direct them to proliferate, differentiate, or remain dormant; these factors include neighboring cells, the extracellular matrix, soluble molecules, and physical stimuli. In disease and aging states, stable or transitory changes in the microenvironment can directly cause SC activation or inhibition in tissue healing as well as functional regulation. Here, we discuss the microenvironmental regulation of the behavior of SC and focus on plasticity approaches by which various environmental factors can enhance the function of SCs and more effectively direct the fate of SCs.展开更多
Bifunctional RNAs that possess both protein-coding and noncoding functional properties were less explored and poorly understood. Here we systematically explored the characteristics and functions of such human bifuncti...Bifunctional RNAs that possess both protein-coding and noncoding functional properties were less explored and poorly understood. Here we systematically explored the characteristics and functions of such human bifunctional RNAs by integrating tandem mass spectrometry and RNA-seq data. We first constructed a pipeline to identify and annotate bifunctional RNAs,leading to the characterization of 132 high-confidence bifunctional RNAs. Our analyses indicate that bifunctional RNAs may be involved in human embryonic development and can be functional in diverse tissues. Moreover, bifunctional RNAs could interact with multiple miRNAs and RNA-binding proteins to exert their corresponding roles. Bifunctional RNAs may also function as competing endogenous RNAs to regulate the expression of many genes by competing for common targeting miRNAs. Finally,somatic mutations of diverse carcinomas may generate harmful effect on corresponding bifunctional RNAs. Collectively,our study not only provides the pipeline for identifying and annotating bifunctional RNAs but also reveals their important gene-regulatory functions.展开更多
In this work FePt-Au heterostructured nanocrystals （HNCs） such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods （NRs）...In this work FePt-Au heterostructured nanocrystals （HNCs） such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods （NRs）. A study of the growth mechanism revealed that the morphology control of the final products can be correlated with the adsorption sites of hydrogen onto the FePt NRs, which can be manipulated by the amount of the forming gas （At/7% H2） added. Not only the optical characteristic and magnetic properties of the intrinsic materials were retained in the products, but also the FePt-Au HNCs showed the tunable multifunctional properties resulted from the interactions between Au and FePt. Moreover, for methanol oxidation, the FePt-Au HNCs exhibited enhanced catalytic activity and CO tolerance on the catalyst surface compared to commercial Pt catalysts. It is worth noting that as multifunctional units, the FePt-Au HNCs also possess a heterogeneous surface, which could potentially enable their site-specific functionalization for targeting or imaging purposes in biomedical applications. More interestingly, the catalytic properties of the FePt-Au HNCs also endow this material with application potentials in nanocatalysis.展开更多
基金supported by the National Natural Science Foundation of China(21276058,21433003)the State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology)(2014DX10)
文摘Polymer membrane fuel cells represent important sustainable energy devices because their operation involves zero emissions and low temperatures and their components exhibit low toxicity. Among the various components of such cells, the electrocatalyst plays the vital role of enhancing the output power density and/or working lifetime. Over the past several decades, numerous strategies have been proposed to address the challenges of electrocatalyst activity and/or durability. Herein, we review the applications of polyelectrolytes in electrocatalysts, including the enhancement of both catalytic nanoparticles and support materials. The effects of polyelectrolytes with regard to controlling the size, composition and morphology of catalytic nanoparticles, as well as the modification of support materials were summarized. In addition, the future possibilities for the research and development of polyelectrolytes in the field of catalyst design and synthesis are discussed.
文摘Dy Ov sfunctional audit behaviour （DAB） and staff turnover are associated with decreased audit quality （Public ersight Board, 2000）. This study develops and tests a theoretical model that turnover intentions and locus of control as antecedents of attitudes toward DAB survey results from 225 auditors support the theoretical model identifies employee performance, Using a path analysis technique,
基金supported in part by the National Basic Research Program of China(2012CB518103,2012CB518105)National High Technology Research and Development Program of Ministry of Science and Technology of China(2013AA020105,2012AA020502)National Natural Science Foundation of China(81121004,81230041,31400822)
文摘Adult stem cells(SCs) exist in all tissues that promote tissue growth, regeneration, and healing throughout life. The SC niche in which they reside provides signals that direct them to proliferate, differentiate, or remain dormant; these factors include neighboring cells, the extracellular matrix, soluble molecules, and physical stimuli. In disease and aging states, stable or transitory changes in the microenvironment can directly cause SC activation or inhibition in tissue healing as well as functional regulation. Here, we discuss the microenvironmental regulation of the behavior of SC and focus on plasticity approaches by which various environmental factors can enhance the function of SCs and more effectively direct the fate of SCs.
基金supported in part by the National High Technology Research and Development Program of China(2015AA020104,2015AA020108)the China Human Proteomics Project(2014DF30030)the National Science Foundation of China(31471239)
文摘Bifunctional RNAs that possess both protein-coding and noncoding functional properties were less explored and poorly understood. Here we systematically explored the characteristics and functions of such human bifunctional RNAs by integrating tandem mass spectrometry and RNA-seq data. We first constructed a pipeline to identify and annotate bifunctional RNAs,leading to the characterization of 132 high-confidence bifunctional RNAs. Our analyses indicate that bifunctional RNAs may be involved in human embryonic development and can be functional in diverse tissues. Moreover, bifunctional RNAs could interact with multiple miRNAs and RNA-binding proteins to exert their corresponding roles. Bifunctional RNAs may also function as competing endogenous RNAs to regulate the expression of many genes by competing for common targeting miRNAs. Finally,somatic mutations of diverse carcinomas may generate harmful effect on corresponding bifunctional RNAs. Collectively,our study not only provides the pipeline for identifying and annotating bifunctional RNAs but also reveals their important gene-regulatory functions.
基金This work was supported in part by National Natural Science Foundation of China （NSFC） （Nos. 90922033 and 20941003）, the National Basic Research Program of China （No. 2010CB934601）, the Doctoral Program （No. 20090001120010）, and New Century Talents of the Education Ministry of China （No. NCET-09-0177）, the Yok Ying Tung Foundation （No. 122043）, the Beijing Outstanding Talent Program （No. 2009D013001000013）, and New Star Program of Beijing Committee of Science and Technology （BCST） （No. 2008B02）.
文摘In this work FePt-Au heterostructured nanocrystals （HNCs） such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods （NRs）. A study of the growth mechanism revealed that the morphology control of the final products can be correlated with the adsorption sites of hydrogen onto the FePt NRs, which can be manipulated by the amount of the forming gas （At/7% H2） added. Not only the optical characteristic and magnetic properties of the intrinsic materials were retained in the products, but also the FePt-Au HNCs showed the tunable multifunctional properties resulted from the interactions between Au and FePt. Moreover, for methanol oxidation, the FePt-Au HNCs exhibited enhanced catalytic activity and CO tolerance on the catalyst surface compared to commercial Pt catalysts. It is worth noting that as multifunctional units, the FePt-Au HNCs also possess a heterogeneous surface, which could potentially enable their site-specific functionalization for targeting or imaging purposes in biomedical applications. More interestingly, the catalytic properties of the FePt-Au HNCs also endow this material with application potentials in nanocatalysis.
