Synthesis and applications of porous non-silica metal oxide submicrospheres

© 2016 Royal Society of Chemistry. Nowadays the development of submicroscale products of specific size and morphology that feature a high surface area to volume ratio, well-developed and accessible porosity for adsorbates and reactants, and are non-toxic, biocompatible, thermally stable and suitable as synergetic supports for precious metal catalysts is of great importance for many advanced applications. Complex porous non-silica metal oxide submicrospheres constitute an important class of materials that fulfill all these qualities and in addition, they are relatively easy to synthesize. This review presents a comprehensive appraisal of the methods used for the synthesis of a wide range of porous non-silica metal oxide particles of spherical morphology such as porous solid spheres, core-shell and yolk-shell particles as well as single-shell and multi-shell particles. In particular, hydrothermal and low temperature solution precipitation methods, which both include various structure developing strategies such as hard templating, soft templating, hydrolysis, or those taking advantage of Ostwald ripening and the Kirkendall effect, are reviewed. In addition, a critical assessment of the effects of different experimental parameters such as reaction time, reaction temperature, calcination, pH and the type of reactants and solvents on the structure of the final products is presented. Finally, the practical usefulness of complex porous non-silica metal oxide submicrospheres in sensing, catalysis, biomedical, environmental and energy-related applications is presented

The study of influential factors of prime-stage female adults toward learning needs.

本研究主要目的在於探討成年婦女的學習需求及其相關因素，樣本的蒐 集以嘉義市青壯期婦女為主。學習需求可分納入情境因素考量的學習需求 與就需要程度考量的學習需求兩大類，青壯期婦女的學習需求以與家庭有 關的知識內容最受婦女重視。影響婦女學習需求的因素為：一、家庭生命 週期僅對婦女的「職業進展」學習需求有影響。二、教育程度對「休閒嗜 好」、「職業進展」的學習需求有影響；對納入情境因素的學習 需求 的影響效果則顯現在「職業進展」及「自我發展」兩個學習領域。三、家 庭收入對「休閒嗜好」的學習需求有影響，對納入情境因素考量的學習需 求的影響 效果則發生在「職業進展」因素。四、就業與否影響婦女 「社會政治」、「職業進展」、「自我發展」及「休閒嗜好」的學 習 需求，對納入情境因素考量的學習需求則全部達到顯著水準。The basic objectives of this study were to investigate the learning needs andseveral related factors in the prime stages of women sampled from Chayi city.Learning needs were evaluated without or with the situation barriers.The results indicated that the most of the sampled women showed greater interests in the area of family-related knowledge. Furthermore, the presented study revealed that family cycle affected the learning needs only on the area of career development. The levels of education also affect the learning needs on the areas of leisure and recreation and career development. However, both career development and self-development were affected by the level of educaton when the situation barriers were put into consiedration. The learning need was also underinfluence of family income. On the other hand, family income showed greater influence on career development. Significant differences in learning need existed between career women and unemployed women in the areas of politics, career development, self-development, and leisure and recreaton when the situation barriers were put into consideration

Peptide-coordination self-assembly for the precise design of theranostic nanodrugs

Peptide-coordination self-assembly demonstrates great potential in the precise design of next-generation theranostic nanodrugs. It has the advantages of high biosafety, versatile system design, easy control over the self-assembled structures, facile incorporation of various functionalities, and greatly enhanced stability of the complex materials as well as their stimuli-responsive assembly and disassembly. All of these merits promote the construction of targeted theranostic systems with highly integrated diagnostic and therapeutic functionalities. This review seeks to provide an up-to-date conclusive observation about the field of peptide-coordination self-assembly for theranostic applications to guide related research. It covers the general principles of peptide-coordination self-assembly for producing structures with controlled morphologies and properties, the strategies for constructing peptide/metal hybrid materials for diagnostic and therapeutic aims, and, more specifically, the strategies and design rules for integrating various functionalities into a single platform for theranostics. (C) 2019 Elsevier B.V. All rights reserved

Spatiotemporal pattern of leprosy in southwest China from 2010 to 2020: an ecological study

Abstract Background Despite many efforts to control leprosy worldwide, it is still a significant public health problem in low- and middle-income regions. It has been endemic in China for thousands of years, and southwest China has the highest leprosy burden in the country. Methods This observational study was conducted with all newly detected leprosy cases in southwest China from 2010 to 2020. Data were extracted from the Leprosy Management Information System (LEPMIS) database in China. The Joinpoint model was used to determine the time trends in the study area. Spatial autocorrelation statistics was performed to understand spatial distribution of leprosy cases. Spatial scan statistics was applied to identify significant clusters with high rate. Results A total of 4801 newly detected leprosy cases were reported in southwest China over 11 years. The temporal trends declined stably. The new case detection rate (NCDR) dropped from 4.38/1,000,000 population in 2010 to 1.25/1,000,000 population in 2020, with an average decrease of 12.24% (95% CI: −14.0 to − 10.5; P < 0.001). Results of global spatial autocorrelation showed that leprosy cases presented clustering distribution in the study area. Most likely clusters were identified during the study period and were frequently located at Yunnan or the border areas between Yunnan and Guizhou Provinces. Secondary clusters were always located in the western counties, the border areas between Yunnan and Sichuan Provinces. Conclusions Geographic regions characterized by clusters with high rates were considered as leprosy high-risk areas. The findings of this study could be used to design leprosy control measures and provide indications to strengthen the surveillance of high-risk areas. These areas should be prioritized in the allocation of resources

Graphene Oxide-Assisted Accumulation and Layer-by-Layer Assembly of Antibacterial Peptide for Sustained Release Applications

Fabrication of antibacterial materials with sustained release of active components is of great importance for long-term antibacterial applications. Graphene oxide (GO) has been found to be an excellent carrier for accumulating the antibacterial peptide of G­(IIKK)₄I-NH₂ and mediating its loading into the layer-by-layer (LBL) films for sustained release applications. G­(IIKK)₄I-NH₂ takes random coiled conformation in monomeric state below 0.17 mM but self-assembles into supramolecular aggregates with α-helical secondary structure at higher concentrations. It can bind onto GO surface in both monomeric and aggregate states to form stable GO@G­(IIKK)₄I-NH₂ composites. Upon binding, the local amphiphilic environment of GO surface induces a conformational transition of G­(IIKK)₄I-NH₂ monomers from random coils to α-helix. The aggregate binding enhances the loading amount greatly. GO (1 mg) can load as high as 1.7 mg of peptide at saturation. This enables the GO@G­(IIKK)₄I-NH₂ composites to serve as reservoirs for sustained release of active G­(IIKK)₄I-NH₂ monomers. Moreover, G­(IIKK)₄I-NH₂ itself shows low efficiency in LBL assembly, whereas the GO@G­(IIKK)₄I-NH₂ composites are ideal LBL assembling units with highly enhanced loading efficiency of G­(IIKK)₄I-NH₂. The LBL films involving degradable poly­(β-amino esters) can realize sustained release of G­(IIKK)₄I-NH₂ for bacteria killing in a well-controlled manner. This study demonstrates an efficient strategy for fabrication of long-durable antibacterial materials and surface coatings by using GO as the carrier for drug accumulation and loading

Peptide-Induced DNA Condensation into Virus-Mimicking Nanostructures

A series of surfactant-like peptides have been designed for inducing DNA condensation, which are all comprised of the same set of amino acids in different sequences. Results from experiments and molecular dynamics simulations show that the peptide’s self-assembly and DNA-interaction behaviors can be well manipulated through sequence variation. With optimized pairing modes between the β-sheets, the peptide of I₃V₃A₃G₃K₃ can induce efficient DNA condensation into virus-mimicking structures. The condensation involves two steps; the peptide molecules first bind onto the DNA chain through electrostatic interactions and then self-associate into β-sheets under hydrophobic interactions and hydrogen bonding. In such condensates, the peptide β-sheets act as scaffolds to assist the ordered arrangement of DNA, mimicking the very nature of the virus capsid in helping DNA packaging. Such a hierarchy affords an extremely stable structure to attain the highly condensed state and protect DNA against enzymatic degradation. Moreover, the condensate size can be well tuned by the DNA length. The condensates with smaller sizes and narrow size distribution can deliver DNA efficiently into cells. The study helps not only for probing into the DNA packaging mechanism in virus but also delineating the role of peptide self-assembly in DNA condensation, which may lead to development of peptide-based gene vectors for therapeutic applications

Direct exfoliation of graphite into graphene in aqueous solutions of amphiphilic peptides

Peptide-mediated solution phase graphene exfoliation.</p