In this letter, a route for synthesizing vertically aligned multi-walled carbon nanotubes（MWCNTs） with branched nanotubes in large area was reported. The branched MWCNTs up to about 30% can be generated by the pyrol...In this letter, a route for synthesizing vertically aligned multi-walled carbon nanotubes（MWCNTs） with branched nanotubes in large area was reported. The branched MWCNTs up to about 30% can be generated by the pyrolysis of iron（Ⅱ） phthalocyanine in presence of thiol under Ar/H2 at 800900℃. The growth mechanism of the branched nanotubes was proposed and the possible reason that thiol enhanced branched nanotubes growth is discussed. The as-prepared samples provide a suitable candidate to investigate the special electrical or thermal properties of CNTs with branched structures further.展开更多
A method of determining branching parameter of lacquer polysaccharide wasestablished by acid-base back-titration of terminal uronic acid of branches. The branchingfactors obtained are in agreement with the values dete...A method of determining branching parameter of lacquer polysaccharide wasestablished by acid-base back-titration of terminal uronic acid of branches. The branchingfactors obtained are in agreement with the values determined by colorimetric method withcarbazole and the results estimated by using Zimm-Stockmayer equation from viscositydata. Influences of molecular weights and branching factors of five fractions of lacquerpolysaccharide on the bioactivities were studied. The results show that the polysaccharideshave bioactivities in motivating the growth of leucocytes, and the effect increases with thedecrease of molecular weight and branching factor in the range studied (17×10~4 >M_w>4×10~4).展开更多
The application of the adaptive growth method is limited because several key techniques during the design process need manual intervention of designers. Key techniques of the method including the ground structure cons...The application of the adaptive growth method is limited because several key techniques during the design process need manual intervention of designers. Key techniques of the method including the ground structure construction and seed selection are studied, so as to make it possible to improve the effectiveness and applicability of the adaptive growth method in stiffener layout design optimization of plates and shells. Three schemes of ground structures, which are comprised by different shell elements and beam elements, are proposed. It is found that the main stiffener layouts resulted from different ground structures are almost the same, but the ground structure comprised by 8-nodes shell elements and both 3-nodes and 2-nodes beam elements can result in clearest stiffener layout, and has good adaptability and low computational cost. An automatic seed selection approach is proposed, which is based on such selection rules that the seeds should be positioned on where the structural strain energy is great for the minimum compliance problem, and satisfy the dispersancy requirement. The adaptive growth method with the suggested key techniques is integrated into an ANSYS-based program, which provides a design tool for the stiffener layout design optimization of plates and shells. Typical design examples, including plate and shell structures to achieve minimum compliance and maximum bulking stability are illustrated. In addition, as a practical mechanical structural design example, the stiffener layout of an inlet structure for a large-scale electrostatic precipitator is also demonstrated. The design results show that the adaptive growth method integrated with the suggested key techniques can effectively and flexibly deal with stiffener layout design problem for plates and shells with complex geometrical shape and loading conditions to achieve various design objectives, thus it provides a new solution method for engineering structural topology design optimization.展开更多
Salivary glands provide saliva to maintain oral health, and a loss of salivary gland function substantially decreases quality-of-life. Understanding the biological mechanisms that generate salivary glands during embry...Salivary glands provide saliva to maintain oral health, and a loss of salivary gland function substantially decreases quality-of-life. Understanding the biological mechanisms that generate salivary glands during embryonic development may identify novel ways to regenerate function or design artificial salivary glands. This review article summarizes current research on the process of branchingmorphogenesis of salivary glands, which creates gland structure during development. We highlight exciting new advances and opportunities in studies of cell-cell interactions, mechanical forces, growth factors, and gene expression patterns to improve our understanding of this important process.展开更多
Purpose: To investigate the short-term efficacy and safety of intravitreal aflibercept in a case series of patients from Taiwan, China, with macular edema secondary to branch retinal vein occlusion(BRVO).Methods: A to...Purpose: To investigate the short-term efficacy and safety of intravitreal aflibercept in a case series of patients from Taiwan, China, with macular edema secondary to branch retinal vein occlusion(BRVO).Methods: A total of 32 patients with macular edema associated with BRVO,.without prior macular laser or other intervention, were enrolled consecutively from September 2013 to February 2015..The cases received single 2 mg injections of intravitreal aflibercept..Primary outcome measures included changes in central foveal thickness.(CFT;.1 mm increments by spectral-domain optic coherence tomography).and best corrected visual acuity.(BCVA),.determined at 1,.2,.and 3months after the injection. Complications after injections were recorded. The changes in CFT and BCVA were compared with Wilcoxon sign-rank tests.Results:.The CFT was significantly reduced and the BCVA was significantly improved at 1, 2, and 3 months after injection(all P < 0.05). Tomography findings revealed no recurrence within 3 months. No systemic thromboembolic events,elevated intraocular pressure, retinal detachment, or infectious endophthalmitis occurred following injection.Conclusion:.Single intravitreal aflibercept may be useful in treating macular edema associated with BRVO within 3months. No adverse systemic or ocular effects were found in this case series.展开更多
Nonstable growth of Al-Si eutectic in constrained condition has been investigated by means of change of the withdrawing rate in an unidirectional solidification system,In constant acceleration growth,a retarded effect...Nonstable growth of Al-Si eutectic in constrained condition has been investigated by means of change of the withdrawing rate in an unidirectional solidification system,In constant acceleration growth,a retarded effect of response of eutectic interflake spacing on the growth rate has been observed.The response mechanisms are cluster-branching and local termination extension of Si-phase.In constant deceleration growth,the cluster-branching and termina- tion mechanisms of silicon still control adjustment of the interflake spacing,but the spacing is determined by the initial growth rate and does not respond to the decreasing growth rate.展开更多
基金supported in part by grants from NSFC (51025207, 21173159)NSFZJ (R4090137)863 project (2012AA02A104)
文摘In this letter, a route for synthesizing vertically aligned multi-walled carbon nanotubes（MWCNTs） with branched nanotubes in large area was reported. The branched MWCNTs up to about 30% can be generated by the pyrolysis of iron（Ⅱ） phthalocyanine in presence of thiol under Ar/H2 at 800900℃. The growth mechanism of the branched nanotubes was proposed and the possible reason that thiol enhanced branched nanotubes growth is discussed. The as-prepared samples provide a suitable candidate to investigate the special electrical or thermal properties of CNTs with branched structures further.
文摘A method of determining branching parameter of lacquer polysaccharide wasestablished by acid-base back-titration of terminal uronic acid of branches. The branchingfactors obtained are in agreement with the values determined by colorimetric method withcarbazole and the results estimated by using Zimm-Stockmayer equation from viscositydata. Influences of molecular weights and branching factors of five fractions of lacquerpolysaccharide on the bioactivities were studied. The results show that the polysaccharideshave bioactivities in motivating the growth of leucocytes, and the effect increases with thedecrease of molecular weight and branching factor in the range studied (17×10~4 >M_w>4×10~4).
基金supported by National Natural Science Foundation of China(Grants No.50875174,51175347)Innovation Program of Shanghai Municipal Education Commission(Grant No.13ZZ114)Capacity Building Project of Local University of Shanghai Municipal Science and Technology Commission(Grant No.13160502500)
文摘The application of the adaptive growth method is limited because several key techniques during the design process need manual intervention of designers. Key techniques of the method including the ground structure construction and seed selection are studied, so as to make it possible to improve the effectiveness and applicability of the adaptive growth method in stiffener layout design optimization of plates and shells. Three schemes of ground structures, which are comprised by different shell elements and beam elements, are proposed. It is found that the main stiffener layouts resulted from different ground structures are almost the same, but the ground structure comprised by 8-nodes shell elements and both 3-nodes and 2-nodes beam elements can result in clearest stiffener layout, and has good adaptability and low computational cost. An automatic seed selection approach is proposed, which is based on such selection rules that the seeds should be positioned on where the structural strain energy is great for the minimum compliance problem, and satisfy the dispersancy requirement. The adaptive growth method with the suggested key techniques is integrated into an ANSYS-based program, which provides a design tool for the stiffener layout design optimization of plates and shells. Typical design examples, including plate and shell structures to achieve minimum compliance and maximum bulking stability are illustrated. In addition, as a practical mechanical structural design example, the stiffener layout of an inlet structure for a large-scale electrostatic precipitator is also demonstrated. The design results show that the adaptive growth method integrated with the suggested key techniques can effectively and flexibly deal with stiffener layout design problem for plates and shells with complex geometrical shape and loading conditions to achieve various design objectives, thus it provides a new solution method for engineering structural topology design optimization.
基金Supported by the Intramural Research Program of the National Institute of Dental and Craniofacial Research,NIH
文摘Salivary glands provide saliva to maintain oral health, and a loss of salivary gland function substantially decreases quality-of-life. Understanding the biological mechanisms that generate salivary glands during embryonic development may identify novel ways to regenerate function or design artificial salivary glands. This review article summarizes current research on the process of branchingmorphogenesis of salivary glands, which creates gland structure during development. We highlight exciting new advances and opportunities in studies of cell-cell interactions, mechanical forces, growth factors, and gene expression patterns to improve our understanding of this important process.
文摘Purpose: To investigate the short-term efficacy and safety of intravitreal aflibercept in a case series of patients from Taiwan, China, with macular edema secondary to branch retinal vein occlusion(BRVO).Methods: A total of 32 patients with macular edema associated with BRVO,.without prior macular laser or other intervention, were enrolled consecutively from September 2013 to February 2015..The cases received single 2 mg injections of intravitreal aflibercept..Primary outcome measures included changes in central foveal thickness.(CFT;.1 mm increments by spectral-domain optic coherence tomography).and best corrected visual acuity.(BCVA),.determined at 1,.2,.and 3months after the injection. Complications after injections were recorded. The changes in CFT and BCVA were compared with Wilcoxon sign-rank tests.Results:.The CFT was significantly reduced and the BCVA was significantly improved at 1, 2, and 3 months after injection(all P < 0.05). Tomography findings revealed no recurrence within 3 months. No systemic thromboembolic events,elevated intraocular pressure, retinal detachment, or infectious endophthalmitis occurred following injection.Conclusion:.Single intravitreal aflibercept may be useful in treating macular edema associated with BRVO within 3months. No adverse systemic or ocular effects were found in this case series.
文摘Nonstable growth of Al-Si eutectic in constrained condition has been investigated by means of change of the withdrawing rate in an unidirectional solidification system,In constant acceleration growth,a retarded effect of response of eutectic interflake spacing on the growth rate has been observed.The response mechanisms are cluster-branching and local termination extension of Si-phase.In constant deceleration growth,the cluster-branching and termina- tion mechanisms of silicon still control adjustment of the interflake spacing,but the spacing is determined by the initial growth rate and does not respond to the decreasing growth rate.
