Effect of Fiber Length on Carbon Nanotube-Induced Fibrogenesis

Given their extremely small size and light weight, carbon nanotubes (CNTs) can be readily inhaled by human lungs resulting in increased rates of pulmonary disorders, particularly fibrosis. Although the fibrogenic potential of CNTs is well established, there is a lack of consensus regarding the contribution of physicochemical attributes of CNTs on the underlying fibrotic outcome. We designed an experimentally validated in vitro fibroblast culture model aimed at investigating the effect of fiber length on single-walled CNT (SWCNT)-induced pulmonary fibrosis. The fibrogenic response to short and long SWCNTs was assessed via oxidative stress generation, collagen expression and transforming growth factor-beta (TGF-β) production as potential fibrosis biomarkers. Long SWCNTs were significantly more potent than short SWCNTs in terms of reactive oxygen species (ROS) response, collagen production and TGF-β release. Furthermore, our finding on the length-dependent in vitro fibrogenic response was validated by the in vivo lung fibrosis outcome, thus supporting the predictive value of the in vitro model. Our results also demonstrated the key role of ROS in SWCNT-induced collagen expression and TGF-β activation, indicating the potential mechanisms of length-dependent SWCNT-induced fibrosis. Together, our study provides new evidence for the role of fiber length in SWCNT-induced lung fibrosis and offers a rapid cell-based assay for fibrogenicity testing of nanomaterials with the ability to predict pulmonary fibrogenic response in vivo.     

Electrohydrodynamic atomization (EHDA) of high-conductivity pure solvent

ABSTRACT

In this study, the effects of flow rate, liquid conductivity and neutralizer strength on the operating and output characteristics are examined for an Electrohydrodynamic atomization (EHDA)-based aerosol generator system, designed and built in our laboratory. Ethylene glycol is used for generating the droplets. It is seen that stable cone-jet mode could be obtained for solvent conductivity as high as 240 μS/cm. While the output number concentration was found to increase with both flow rate and conductivity, the mean particle diameters decreased with increasing conductivity and increased with flow rate. The mean droplet size and output number concentration are found to be about three times more sensitive to changes in conductivity as compared to that of flow rate in the range of 26–150 μS/cm. It is also observed that throughput from the system is strongly dependent on the strength of the charge neutralizer. In the present setup, 8 μCi ²⁴¹Am bipolar neutralizer in axisymmetric configuration was found to be sufficient to neutralize the generated droplets.     

Gain Enhancement of Antipodal Vivaldi Antenna for 5G Applications Using Metamaterial

The proposed system portrays the application space examination of a diverse cryptosystem processor with dynamic reconfiguration abilities. It is appropriate to a variety of signal processing application domains namely telecommunications, image processing, video coding and cryptographic processing. To differentiate between application spaces of the processor, the performance is correlated with cutting edge devices, taking ability to program, energy efficiency and computational potential as the important factors. In general the conventional method of computation is processed by means of Virtual Secure Circuit (VSC) on Advanced Encryption Standard (AES) and performance of the device Field Programmable Gate Array (FPGA) after implementation is analyzed in terms of delay and throughput. In the conventional method area overhead and power consumption are less where as the architecture lags in performance and throughput. It has been overcome through the fully parallel pipelined Architecture of the VSC on AES which outperforms the existing method in terms of performance and throughput. The energy efficiency and performance are considerably more important than processor that are used for general purpose, while still preserving a Convenient approach of programming that mainly bank on software oriented languages. The exploit of VSC based AES is to formulate the cryptographic processor held against Side Channel Attacks like attacks based on power supply and electromagnetic signals. Then the experimental result shows the promising outcomes when compared to previous methods.

     

Detecting plagiarized mobile apps using API birthmarks

This paper addresses the problem of detecting plagiarized mobile apps. Plagiarism is the practice of building mobile apps by reusing code from other apps without the consent of the corresponding app developers. Recent studies on third-party app markets have suggested that plagiarized apps are an important vehicle for malware delivery on mobile phones. Malware authors repackage official versions of apps with malicious functionality, and distribute them for free via these third-party app markets. An effective technique to detect app plagiarism can therefore help identify malicious apps. Code plagiarism has long been a problem and a number of code similarity detectors have been developed over the years to detect plagiarism. In this paper we show that obfuscation techniques can be used to easily defeat similarity detectors that rely solely on statically scanning the code of an app. We propose a dynamic technique to detect plagiarized apps that works by observing the interaction of an app with the underlying mobile platform via its API invocations. We propose API birthmarks to characterize unique app behaviors, and develop a robust plagiarism detection tool using API birthmarks.     

Correction to: Wideband Antipodal Vivaldi Antenna Using Metamaterial for Micrometer and Millimeter Wave Applications

Journal of Infrared, Millimeter, and Terahertz Waves -     

Maximum Power Point Tracking Using Disturbance Observer-Based Sliding Mode Control for Estimation of Solar Array Voltage

Abstract

The output power of solar panel in photovoltaic systems is affected by changes in environmental and load conditions. Most currently developed MPPT control algorithms require measurements of panel output voltage, output current, and converter output voltage. In this paper, a new scheme that can cater to uncertainties in the environmental and load condition, is developed using a disturbance observer-based sliding mode control (DOSMC). The proposed DOSMC scheme obviates the need of using a panel output voltage sensor. The proposed scheme does not use a discontinuous control, thereby overcoming the problems of chatter normally associated with the conventional sliding mode control (SMC). The stability is proven in the sense of ultimate boundedness. The proposed scheme is validated by extensive simulation and laboratory experimentation under various scenarios of irradiation, temperature, and load conditions and compared with two existing popular schemes.     

Effect of solvents on properties of the ultrasound assisted synthesized ceria nanoparticles and its performance as an adsorbent

The present study revealed a facile, ultrasound assisted ceria nanoparticle synthesis route by the reduction of cerium nitrate hexahydrate in different solvents at room temperature. The different solvents employed were methanol (MeOH), ethylene glycol (EG), water (aq) and isopropyl alcohol (IPA). The ceria nanoparticles were synthesized without the use of any capping agent in 20?min. The yield obtained was around 90% for the synthesized ceria samples. As synthesized ceria nanoparticles were characterized by X-ray diffraction (XRD), Field emission gun scanning electron microscopy (FEG-SEM), Brunauer Emmett Teller (BET) and zeta (ζ) potential in order to determine the influence of solvent on the physical properties of ceria nanoparticles. All the ceria samples illustrated a predominant spherical shape with the size in the range of 5–20?nm. It was found that interaction of the solvent with ceria nanoparticles in the presence of ultrasound plays an important role in modulating crystallite size, surface charge and its adsorption performance for a xylene milling yellow 6G dye. Among all the sonicated ceria samples, IPA mediated ceria exhibited highest positive zeta potential and hence was found to be proficient for the complete removal of dye in 15?min. Furthermore, the adsorption of the yellow milling dye on the surface of (IPA mediated) sonicated ceria sample has shown to follow pseudo-first order kinetic model. The non-sonicated sample (prepared in MeOH solvent without ultrasound) shows negligible dye adsorption while sonicated sample reveals 50% removal of XMY dye due to the difference in zeta potential values resulted from the cavitation effects.