Electrochemical Reduction and Deposition of Reduced Graphene Oxide/Manganese Oxide Composite for Supercapacitor Applications via Pulse-Chronoamperometry

The reduced graphene oxide/manganese oxide composite was deposited on the nickel current collector using the Pulse-Chronoamperometry method in a mixture of graphene oxide dispersion and manganese acetate as the precursor. The graphene oxide (GO) was electrochemically reduced to reduced graphene oxide (rGO) and deposited with manganese oxide (MnOx) at the same time. The effects of manganese acetate (Mn(Ac)2) concentration, deposition temperature, voltage and time on the specific capacitance of rGO/MnOx electrode were investigated. The electrochemical properties were characterized using galvanostatic charge-discharge and cyclic voltammetry. The effects of electrochemical reduction and deposition parameters on the specific capacitance of rGO/MnOx electrode were studied using Central Composite Design methodology and a 2 factors interaction model equation was evaluated. The rGO/MnOx electrode synthesized using 0.2 M of Mn(Ac)2, at 70 °C and -1.0 V versus Saturated Calomel Electrode (SCE) with a total deposition time of 800s exhibited a specific capacitance of 665 F/g was obtained at the current density of 5 A/g. The high specific capacitance of rGO/MnOx electrode showed its potential application for the fabrication of supercapacitors. This study provides an environmental friendly, time effective and costs efficiency way to reduce graphene oxide and to deposit the rGO/MnOx composite for electrochemical energy storage application

Cost estimation methods for internet infrastructure deployment in Rural Sarawak: a review

In rural Sarawak, the internet accessibility is low due to unreliable power grids to support telecommunication network and large geographical area. The risk for network infrastructure implementation is high for internet service provider (ISP), thus more practical and accurate cost estimation methods should be used. This paper reviews different types of cost estimation methods and the accuracy and feasibility of each methods are discussed and compared for network infrastructure implementation in rural Sarawak. The unique characteristics of rural Sarawak are considered in this work, including the topography, development of rural areas and acceptance of new technologies. Different cost estimation methods are identified for different senarios and availability of data

Model Study for Outdoor Data Transmission Performance

Network performance for outdoor transmissions are varies according to different environment especially when there was obstacle along the transmission path and therefore the expected performance for outdoor transmissions is unpredictable. These unpredictable performances of outdoor data transmission forced Internet Service Providers (ISPs) to use stronger or better routers to establish the data transmission link. So, the initial investment for the project in a rural area will be higher than urban area due to long-range outdoor transmissions. Normally, this cost will be absorbed by the customers, who will be paying higher subscription fees. But, the income of residents in rural areas is lower than urban areas and the ISP is forced to absorb the extra initial investment by prolonging the projects’ breakeven point. Therefore, this study aimed to a model for estimating average data speed for outdoor Wi-Fi data transmission. The average data speed of outdoor Wi-Fi data transmission was modelled by conducting experiments that simulate real-world wireless transmission. The experiments were conducted by selecting suitable transmitter and receivers. The obstacle used in the experiment was made from aluminum plate which has high attenuation for wireless signals. The experimental data were further validated with actual testing with real-world obstacles. The average percentage error for the outdoor Wi-Fi average data speed model was 24.97%

Development and Application of Outdoor Router Cost Estimation with Parametric Modelling Technique

Internet development is a challenging issue among Internet Server Providers (ISPs) and researchers due to high investment cost and unforeseen risk. The internet accessibilities of those rural areas are low and seem disconnected from the society. Rural areas unable to enjoy the benefits from high-speed Internet. Rural internet development is not prioritized because of low population density and return of investment from urban area development is more favorable. Outdoor equipment such as router, antennas and access points are the main components in Internet development. The accuracy of various cost estimation model is depending on the availability of raw data and data analysis techniques. There is no accurate model that allow ISPs to estimate the cost of outdoor routers for Wireless Fidelity (Wi-Fi) transmission. Those estimations can assist ISPs in risk management and reduce the total project cost. Therefore, this paper aimed to produce and demonstrate a suitable outdoor router cost estimation model. Friis transmission equation and link budget equation were used in this model. Suitable key parameters were selected by using P-value regression analysis. Original key parameters and calculated unique key parameters were utilized in this model to provide better performance and realistic estimated cost. This paper also demonstrated the usage of outdoor router cost estimation model under long-range and short-range wireless data transmission

Cost estimation methods for internet infrastructure deployment in Rural Sarawak: a review

In rural Sarawak, the internet accessibility is low due to unreliable power grids to support telecommunication network and large geographical area. The risk for network infrastructure implementation is high for internet service provider (ISP), thus more practical and accurate cost estimation methods should be used. This paper reviews different types of cost estimation methods and the accuracy and feasibility of each methods are discussed and compared for network infrastructure implementation in rural Sarawak. The unique characteristics of rural Sarawak are considered in this work, including the topography, development of rural areas and acceptance of new technologies. Different cost estimation methods are identified for different senarios and availability of data

Green Synthesis and Characterization of Silver/Chitosan/Polyethylene Glycol Nanocomposites without any Reducing Agent

This paper presents the green synthesis of silver nanoparticles (Ag NPs) in aqueous medium. This method was performed by reducing AgNO3 in different stirring times of reaction at a moderate temperature using green agents, chitosan (Cts) and polyethylene glycol (PEG). In this work, silver nitrate (AgNO3) was used as the silver precursor while Cts and PEG were used as the solid support and polymeric stabilizer. The properties of Ag/Cts/PEG nanocomposites (NCs) were studied under different stirring times of reaction. The developed Ag/Cts/PEG NCs were then characterized by the ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy

Teacher led school-based surveillance can allow accurate tracking of emerging infectious diseases - evidence from serial cross-sectional surveys of febrile respiratory illness during the H1N1 2009 influenza pandemic in Singapore

10.1186/1471-2334-12-336BMC Infectious Diseases12-BIDM

Cellular Robustness Conferred by Genetic Crosstalk Underlies Resistance against Chemotherapeutic Drug Doxorubicin in Fission Yeast

10.1371/journal.pone.0055041PLoS ONE81

Dynamic NF-κB and E2F interactions control the priority and timing of inflammatory signalling and cell proliferation

© Ankers et al. Dynamic cellular systems reprogram gene expression to ensure appropriate cellular fate responses to specific extracellular cues. Here we demonstrate that the dynamics of Nuclear Factor kappa B (NF-κB) signalling and the cell cycle are prioritised differently depending on the timing of an inflammatory signal. Using iterative experimental and computational analyses, we show physical and functional interactions between NF-κB and the E2 Factor 1 (E2F-1) and E2 Factor 4 (E2F-4) cell cycle regulators. These interactions modulate the NF-κB response. In S-phase, the NF-κB response was delayed or repressed, while cell cycle progression was unimpeded. By contrast, activation of NF-κB at the G1/S boundary resulted in a longer cell cycle and more synchronous initial NF-κB responses between cells. These data identify new mechanisms by which the cellular response to stress is differentially controlled at different stages of the cell cycle

A tudor domain protein SPINDLIN1 interacts with the mRNA-binding protein SERBP1 and is involved in mouse oocyte meiotic resumption

Mammalian oocytes are arrested at prophase I of meiosis, and resume meiosis prior to ovulation. Coordination of meiotic arrest and resumption is partly dependent on the post-transcriptional regulation of maternal transcripts. Here, we report that, SPINDLIN1 (SPIN1), a maternal protein containing Tudor-like domains, interacts with a known mRNA-binding protein SERBP1, and is involved in regulating maternal transcripts to control meiotic resumption. Mouse oocytes deficient for Spin1 undergo normal folliculogenesis, but are defective in resuming meiosis. SPIN1, via its Tudor-like domain, forms a ribonucleoprotein complex with SERBP1, and regulating mRNA stability and/or translation. The mRNA for the cAMP-degrading enzyme, PDE3A, is reduced in Spin1 mutant oocytes, possibly contributing to meiotic arrest. Our study demonstrates that Spin1 regulates maternal transcripts post-transcriptionally and is involved in meiotic resumption.Ting Gang Chew, Anne Peaston, Ai Khim Lim, Chanchao Lorthongpanich, Barbara B. Knowles, Davor Solte