Green tea polyphenol-reduced graphene oxide: derivatisation, reduction efficiency, reduction mechanism and cytotoxicity

This paper reports on the derivatisation, reduction efficiency, reduction mechanism and cytotoxicity of green tea polyphenol-reduced graphene oxide (GTP-RGO). The reduction of graphene oxide (GO) at 90°C using a weight ratio (WR) of GTP/GO=1 resulted in the production of a stable GTP-RGO dispersion in aqueous media, as indicated by the results of ultravioletvisible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and the measurement of zeta potential and electrophoretic mobility. In addition, the results from UV-Vis spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis indicated the comparable reduction ability of GTP relative to the standard reducing agent, hydrazine (N2H4). The removal mechanism of epoxy group from GO via reduction reaction with GTP was investigated by implementing hybrid functional method of Becke-3-parameters-Lee-Yang-Parr (B3LYP)using Gaussian 09 software. The energy and frequency calculations showed that the GO reduction using GTP was more spontaneous and relatively took place faster than the reduction using N2H4, as evidenced by higher entropy change (ΔS) (0.039 kcal/mol·K) and lower Gibbs free energy (ΔG) barrier (58.880 kcal/mol).The cytotoxicities of GO and GTP-RGO samples were evaluated against human colonic fibroblasts cells (CCD-18Co). The GO sample was determined to be toxic even at low concentration (6.25 μg/mL), while the GTP-RGO sample possesses notably low toxicity at the same concentration. The cell culture experiments revealed that the incorporation of GTP led to a decrease in the toxicity of GTP-RGO samples

Analisis Kinerja Keuangan Ditinjau dari Segi Likuiditas, Struktur Modal dan Profitabilitas pada Perusahaan Publik Sektor Aneka Industri yang Terdaftar di Bej Periode 2000-2004

The objective of research is to identify the development of financial performance viewed from liquidity, capital structure, and profitability on public companies from miscellaneous industry sector that listed in Jakarta Stock Exchange during period 2000-2004. Selecting of sample is done by purposive sampling method that it is judgment sampling under condition : 1) public companies from miscellaneous industry sector that listed in Jakarta Stock Exchange during period 2000-2004; 2) Financial report is limited on balance and income statement of public companies from miscellaneous industry sector that listed in Jakarta Stock Exchange during period 2003-2004 that they are available completely in library of Jakarta Stock Exchange. Descriptive statistic is used to see the development of financial performance viewed from liquidity, capital structure, and profitability on public companies from miscellaneous industry sector that listed in Jakarta Stock Exchange during period 2000-2004; and Kruskal-Wellis statistic is used to see if there is significant difference of financial performance viewed from liquidity, capital structure, and profitability on public companies from miscellaneous industry sector that listed in Jakarta Stock Exchange during period 2000-2004. Result of research shows financial performance of public companies from micellaneous industry sector that listed in Jakarta Stock Exchange during period 2000-2004 viewed from liquidity, capital structure, and profitability (ROI) are not good except profitability (REO). Result of research also shows during period 2000-2004 there are not significant difference of financial performance viewed from liquidity, and capital structure on public companies from miscellaneous industry sector, except viewed from profitability (ROI and ROE)

Self-consistent Green function approach for calculations of electronic structure in transition metals

We present an approach for self-consistent calculations of the many-body Green function in transition metals. The distinguishing feature of our approach is the use of the one-site approximation and the self-consistent quasiparticle wave function basis set, obtained from the solution of the Schrodinger equation with a nonlocal potential. We analyze several sets of skeleton diagrams as generating functionals for the Green function self-energy, including GW and fluctuating exchange sets. Their relative contribution to the electronic structure in 3d-metals was identified. Calculations for Fe and Ni revealed stronger energy dependence of the effective interaction and self-energy of the d-electrons near the Fermi level compared to s and p electron states. Reasonable agreement with experimental results is obtained

Evaluasi Penerapan Aspek 5M Dalam Penggunaan Tracer di Unit Penyimpanan Rekam Medis RSIA Husada Bunda Malang

Tracer is an outguide when medical record documents are borrowed or taken by health workers in health services. Tracers at RSIA Husada Bunda is still not appropriate, seen in terms of the design of the marker slip which does not include the destination poly and the use of tracers is still done manually. This study aims to evaluate the use of tracers based on 5M aspects in the medical record unit of RSIA Husada Bunda. This research was conducted using a descriptive qualitative method with instruments in the form of observations and interviews conducted to the head of medical records and medical records officers in the storage section. The results of this study show that in the Man aspect there are discrepancies related to HR criteria in the medical records unit. In the Material aspect, the tracer uses semihard materials, while the use of the tracer refers to a special method, namely the SOP. The application of the tracer in terms of Machine still uses a written manual. In supporting all activities in the medical records unit, it is supported by Money (budget funds) and some are allocated for training activities and seminars. Overall, the use of tracers in the medical records unit of RSIA Husada Bunda has been relatively effective but still needs a stage of improvement in several aspects. Improvements related to the use of tracers can be in the form of updates to tracer materials, redesign of marker slips, and maximizing the use of machines in operational activities using tracers

The Synthesis And Applications Of Carbon Nanotubes From Natural Gas.

Carbon Nanotubes are newly discovered carbon: it is fullerene related structures but a fullerene's carbon form a sphere while a nanotube is cylindrical. According to theoretical predictions of carbon nanotubes. the tubular fullerene. may possess extraordinary physical and chemical properties. Due to its unique properties, carbon nanotubes have found a variety of potential applications in advance technologies; including nanoelectronics, biomedical, electromagnetics, electrochemical, composite. mass storage, etc. They provide an alternative to current technology to achieve better performance and smaller sizing in numerous applications. It brings technologies of all area to the edge and beyond expectation in the past. This paper will cover the outstanding properties of carbon nanotubes and the applications of carbon nanotubes

Review Of Carbon Nanotubes Growth And Synthesis.

Carbon nanotubes are tubular nanostructures derived from rolled graphene planes. Carbon nanotubes are fullerenes related structures but a fullerenes's carbon form a sphere; while a nanotubes are cylindrical. The growth mechanism of carbon nanotubes depend on the synthesis method

A low Complexity Wireless Gigabit Ethernet IFoF 60 GHz H/W Platform and Issues

6 pagesInternational audienceThis paper proposes a complete IFoF system architecture derived from simplified IEEE802.15.3c PHY layer proposal to successfully ensure near 1 Gbps on the air interface. The system architecture utilizes low complexity baseband processing modules. The byte/frame synchronization technique is designed to provide a high value of preamble detection probability and a very small value of the false detection probability. Conventional Reed-Solomon RS (255, 239) coding is used for Channel Forward Error Correction (FEC). Good communication link quality and Bit Error Rate (BER) results at 875 Mbps are achieved with directional antennas

Simultaneous 3D reconstruction and implant placement using allogenic laminar bone membranes in atrophic Mandible. A comparative clinical study

Objective: to compare the outcome of allogenic bone sheets clinically and radiographically in posterior mandibular vertical augmentation in Luhr class III cases with simultaneous implant placement using autogenous versus xenografts. Patients and methods: this study was based on a total of 12 implants placed in 4 patients, 2 of which were males and 2 females. Patients were divided into 2 groups, both treated with implants placed with exposed threads 3 mm crestally and covered buccolingually with the laminar bone membrane; group 1 received autogenous bone obtained from the same surgical site using 4.5 diameter ACM bur mixed with PRP and packed around the crestally exposed implant threads. Group 2 received xenograft bone particles mixed with PRP and packed around the crestally exposed implant threads in the same manner. Results: CBCT was done pre-operatively, immediate post-operatively and 4 months post-operatively for each implant to compare the bone gain radiographically. In group 1, the mean amount of residual bone height pre-operatively was 7.8 mm (SD 0.86) and increased to 14.44 mm (SD 1.75) and 14.1 mm (SD 1.85) immediate and 4 months post-operatively, respectively. The mean amount of bone gain after 4 months was 6.3 mm, denoting a minimal amount of graft loss during the first 4 postoperative months was 0.27 mm (less than 2%). In group 2, the mean amount of residual bone height pre-operatively was 8.37 mm (SD 0.99) and increased to 12.86 mm (SD 1.75) and 12.53 mm (SD 1.65) immediate and 4 months post-operatively, respectively. The mean amount of bone gain after 4 months was 4.16 mm, denoting a minimal amount of graft loss during the first 4 postoperative months was 0.33 mm (less than 3%). Upon comparing bone gain in both groups, Group I (Autogenous) had a bone gain of 6.33 mm versus 4.16 mm for Group II (Xenograft). Denoting more gain in Group I (autogenous). While the amount of graft loss between the immediate and 4 months postoperative CBCT was less than 2% and less than 3% in the autogenous versus the xenograft group respectively . Conclusion: Cases initially lacking keratinized mucosa will need soft tissue intervention along with this technique. Exposure after 4 months appeared to have been too early, which lead to bone loss and exposed threads. Bilateral augmentation has led to patients using the grafted edentulous sites for mastication early following soft tissue healing, prior to prosthetics, which might suggest that tooth-bounded posterior edentulous sites might be a better candidate for such technique. Results were clinically different than radiographically in the CBCT, so longer lag time is recommended before loading. Keywords: mandibular atrophy, bone graft, implants, laminar bone sheet

Optimization of ISSI Stock Portfolio using Single Index Models in 2013-2017

The article's abstract is not available.   &nbsp