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Ni/NiOx core-shell nanoparticles were used to improve the water splitting efficiency and stability of an n-GaN photoanode. Nanoparticles were fabricated by thermal annealing and oxidizing a Ni thin film deposited on an n-GaN substrate. The performance of water splitting was investigated by varying Ni film thickness and oxidation time, which led to different nanoparticle distribution and NiOx thickness in the core-shell structure. Nanoparticles fabricated from a thinner Ni film led to a smaller particle-to-particle spacing. It allowed holes in n-GaN to diffuse to nanoparticle catalysts in a shorter distance for water splitting reaction, thereby providing higher photocurrent and better protection against oxidation corrosion. Ni/NiOx core-sell nanoparticles obtained from partial oxidation showed higher photocurrent than sole Ni or fully oxidized NiOx nanoparticles. It is attributed to the optimization between having more NiOx for reaction centers and keeping NiOx thin for easy hole transport from n-GaN across NiOx to NiOx/electrolyte interface for reaction.

Two types of ZnO nanostructures were electro-hydrothermally deposited on mesh 100 and 200 copper grids. To investigate the nanostructures, multiple material analyses were used to analyze the material properties. FESEM images indicate that nanoflow-ers/nanorods could be grown on the mesh 100 copper grids while a single layer of ZnO nanorods could be grown on the mesh 200 copper grids. Since the size of the grid holes might influence the chemical reactions during the growth of the nanostructures, all the other material analyzes also reveale1 distinct material characteristics of these two types of nanostructures on the copper grid. Based on the experimental results, modulating the ZnO nanostructure will be helpful for future applications of ZnO nanostructures on copper substrates.

ZnO structures were electro-hydrothermally grown on copper and silver wires. To characterize the structures, multiple analyses including field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and photoluminescence measurements were performed on the ZnO structures on the wires. Results indicate that ZnO nanoflakes were densely deposited on the silver wire but poor ZnO structures were grown on the copper wire. Furthermore, OD 600 antibacterial tests revealed that ZnO flakes on the silver wire exhibited better antibacterial capability than the silver wire without ZnO nanoflakes. Because of possible integration with silver-related materials and flexibility of wire structures, ZnO nanoflake-coated silver wires have potentials for future antiseptic and biomedical applications.

In this study, we address process how the ZnO nanorods were deposited on GaN substrates with spin-coating by using the hydro-thermal methods. After ZnO was spin coated, the samples were annealed with different temperatures to incorporate with Au nano particles. Multiple material analyses, such as the field emission scanning electron microscopy (FESEM), the energy dispersive X-ray spectroscopy (EDX) and the X-ray diffraction (XRD) analyses were carried out to characterize the Au nanoparticles/ZnO nanorods/GaN nanocomposites.

// Chien-Hsing Lee 1 , Sheng-Chiang Su 1 , Chi-Fu Chiang 2 , Chu-Yen Chien 2 , Chia-Chen Hsu 2 , Tzu-Yi Yu 3 , Shih-Ming Huang 3 , Yi-Shing Shieh 4 , Hong-Wei Kao 5 , Chien-Sung Tsai 6 , Yi-Jen Hung 1 and Chih-Yuan Lin 6 1 Division of Endocrinology and Metabolism, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 2 Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan 3 Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan 4 Department of Oral Diagnosis and Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 5 Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 6 Division of Cardiovascular Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan Correspondence to: Chih-Yuan Lin, email: linrock@ms26.hinet.net Keywords: estrogen; sirtuin 1 (SIRT1); vascular smooth muscle cell; ovariectomy Received: September 13, 2017 Accepted: October 27, 2017 Published: November 10, 2017 ABSTRACT Background: There are sex differences in the incidence and severity of cardiovascular disease. Although an estrogen-mediated vasculoprotective effect is widely accepted, clinical trial results have been conflicting and the detailed mechanisms are still unclear. Sirtuin 1 (SIRT1), a class III histone deacetylase, may protect against vascular aging and atherosclerosis; however, the effects of estrogen on SIRT1 expression and vascular smooth muscle cell (VSMC) behavior remain unknown. Materials and Methods: We ovariectomized (OVX) female, wild-type, C57BL/6J mice, which were randomized into non-estrogen- and estrogen-supplemented groups. We also treated A7r5 VSMCs with 17-β-estradiol and resveratrol, a SIRT1 activator, in vitro , and measured the expression of SIRT1 and apoptotic markers, as well as proliferation, viability, and migration. Results: Aortic tissue from OVX mice exhibited marked VSMC hyperplasia and upregulation of SIRT1, which was reversed by 17-β-estradiol supplementation, as assessed by western blotting and immunohistochemical staining. In vitro , 17-β-estradiol downregulated SIRT1 expression in a dose- and time-dependent manner, increased apoptosis, and reduced proliferation, viability, and migration. Resveratrol reversed these effects through the activation of SIRT1. Estrogen appeared to mediate its effects through the Akt and ERK pathways. Conclusions: Estrogen may regulate cardiovascular health via the expression of SIRT1, possibly through the AKT and ERK signaling pathways.

The dose-response relationship of the water-soluble carbohydrate concentrate (WSCC) from wild grape ( Vitis thunbergii Sieb.Zucc.) on intestinal health was investigated in this study. WSCC contained carbohydrates up to 71.9 g/100 g, including arabinose-rich pectic polysaccharide, hemicelluloses, glucose, and fructose. The consumption of WSCC (0.5 and 1.5 g/100 g of diet) effectively (P0.05) shortened gastrointestinal transit time (-62.3 to -63.0%), decreased toxic cecal ammonia (-59.3 to -63.0%) and daily fecal ammonia output (-29.7 to -41.4%), decreased the activities of fecal β-glucuronidase (-78.6%), β-glucosidase (-80.5 to -87.5%), mucinase (-64.6 to -72.7%), and urease (-83.2 to -86.0%), increased fecal moisture content (116-129%), and also increased short-chain fatty acid levels in cecal contents (1.8-3.3-fold). These findings suggested that consumption of wild grape WSCC might diminish the exposure of intestinal mucosa to toxic ammonia and other detrimental compounds and, hence exert, favorable effects on improving gastrointestinal milieu.

This work investigates the morphology of GaN etched in hydrogen (H 2 ) at different temperatures, the activation energies of the rate-limiting steps of H 2 etching, and the overgrowth on a H 2 -etched GaN template. The surfaces of GaN have different profiles after being etched in H 2 ; they resemble a plane decorated with columns and mooring posts in a low-temperature etching condition, and with deep cavities in a high-temperature etching condition. The etched profiles show that H 2 etching has controllable etching directions: vertical and lateral. In a low-temperature condition, H 2 etching has both vertical and lateral etching directions; however, in a high-temperature condition, it has only the vertical etching direction. The activation energies of the rate-limiting steps under etching pressures of 100 and 700 Torr are estimated to be 3.22 and 3.77 eV, respectively. A thick GaN layer has been grown on a H 2 -etched GaN template, and it has self-separated from the underlying sapphire substrate.

In this research, reduced graphene oxide was incorporated into the ZnO seed layer to modulate the rod diameter of ZnO nanorods (NRs) during solgel/hydrothermal growth. To characterize the reduced graphene oxide incorporated ZnO NRs, multiple material analysis techniques including field-emission scanning electron microscopy, surface contact angle measurements, X-ray diffraction, and photoluminescence were used to explore distinct properties of these size modulatable NRs. Results indicate ZnO NRs with smaller diameters could be observed with more reduced graphene oxide added into the ZnO seed layer. Furthermore, better crystallinity, higher hydrophobicity and lower defect concentration could be obtained with more amount of reduced graphene oxide added into the ZnO seed layer. The modulatable reduced graphene oxide-incorporated ZnO NRs growth is promising for future ZnO NRs based nanodevice applications.