Institute for Advanced Science Convergence

Dulles Town Center, VA, United States

Institute for Advanced Science Convergence

Dulles Town Center, VA, United States
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Bolgen N.,Mersin University | Vaseashta A.,Institute for Advanced science Convergence
IFMBE Proceedings | Year: 2016

Electrospinning is a process in which polymer fibers are produced with diameters down to the nanometer range through the action of an electric field imposed on a polymer solution/melt. Distinct properties that make electrospun nanofibrous materials unique are their high surface area, porosity, tensile strength and high extensibility. Indeed the size of the fibers down to nanometer scale make the final structures unique. And since the structure of the nanofibers is very similar to the extracellular matrix, many applications of them are proposed to be used in biomedicine especially for tissue engineeri2ng applications. Many polymers were used to prepare electrospun nanofibers including natural and synthetic ones. Poly(ε-caprolactone) (PCL) was used extensively in the tissue engineering field as a synthetic polymer and alternative to natural polymers. The relatively inexpensive production routes, FDA approval, tailorable biodegradability, biocompatibility and easy manipulation make this polymer promising for electrospinning applications. Therefore PCL based electrospun matrices were used in several tissue engineering attempts including skin, bone, vascular and nerve regeneration. This review summarizes the use of electrospun PCL nanofibers in tissue engineering and regenerative medicine applications. © Springer Science+Business Media Singapore 2016.


Khudaverdyan S.,Polytechnic University of Mozambique | Tsaturyan S.,Polytechnic University of Mozambique | Vaseashta A.,Institute for Advanced science Convergence | Vaseashta A.,Claflin University
Meeting Security Challenges Through Data Analytics and Decision Support | Year: 2016

Explosive identification is a contemporary issue in air transportation security. In this work, a new approach is developed for using a portable photospectrometer with a selective sensitivity sensor, namely a photodiode, to detect and identify explosives. Explosive mixtures in natural objects are identified, and quantitative analysis with data display is achieved using photospectrometry. The new physical capability (photodiode) applied in the sensor enables spatial separation and selection of UV and visible waves with calculated spectral accuracy of 5 nm. The developed algorithm for contactless spectral analysis ensures photodetector operation without preliminary calibration. A new approach for passenger-friendly and secure airport security checks is developed. A narrow corridor (1.5-2m wide and 2-3m long) is equipped with sensor tents, and a specific wavelength laser beam generator remotely identifies explosives. The camera in the corridor captures an image of the suspect if explosive detection is triggered by the sensor array. © 2016 The authors and IOS Press. All rights reserved.


Benfdila A.,Mouloud Mammeri University | Benfdila A.,Abdus Salam International Center For Theoretical Physics | Abbas S.,Mouloud Mammeri University | Izquierdo R.,University of Montréal | And 2 more authors.
Nano | Year: 2010

Electronic devices based on carbon nanotubes (CNTs) show potential for circuit miniaturization due to their superior electrical characteristics and reduced dimensionality. The CNT field effect transistors (CNFETs) offer breakthrough in miniaturization of various electronic circuits. Investigation of ballistic transport governing the operation of CNFETs is essential for understanding the device's functional behavior. This investigation is focused on a study of currentvoltage characteristics of device behavior in hard saturation region. The investigation utilizes a set of currentvoltage characteristics obtained on typical devices. This work is an extension of our earlier work describing application of our approach to Si-MOSFET behavior in the saturation region. © 2010 World Scientific Publishing Company.


Ivanov O.,Bulgarian Academy of Science | Vaseashta A.,Institute for Advanced science Convergence
Ceramics International | Year: 2013

A technique for quality control of ceramic materials is proposed based on the surface photo-charge effect. The method is demonstrated and studied in the case of controlling the chemical composition of bricks. Presented experimental results show that samples with different compositions invoke distinctly different electronic signals specific to sample's composition. In particular, it is revealed that the response signal is a function of the percentage of coal slurries added to the brick raw material for energy efficiency. The quality measurements using the proposed technique are express and contactless, and can be performed under the production conditions of brick firing. The obtained results indicate that the described technology could be extended to control the production quality of other raw materials. © 2012 Elsevier Ltd and Techna Group S.r.l.


Aleksanyan A.S.,Armenian National Academy of Sciences | Khudaverdyan S.K.,Armenian National Polytechnical University | Vaseashta A.,Institute for Advanced science Convergence | Vaseashta A.,Claflin University
Polish Journal of Environmental Studies | Year: 2015

Water resources are an integral part of the global hydrologic cycle and are considered among the natural systems most vulnerable to climate change. Research indicates that severe problems related to water will affect the globe around 2030, which will further intensify to attain its peak by 2100 unless a different water management trajectory is strategically implemented. To conduct an accurate climate change impact assessment it is necessary to conduct parametric analysis for vulnerability to assess for each system by constructing a conceptual hydrogeological model that is then transferred to a mathematical model of overall water resources. We present here a case study outlining plausible impacts of climate change on water resources of Armenia, particularly on river ecosystems. Based on this initial study, we propose certain recommendations for the future to reduce, if not reverse in its entirety, the vulnerability trajectory. We further conclude that vulnerability assessment of water resources resulting from climate change, as proposed here, can be applied for different countries and will be of considerable interest worldwide. © 2015, HARD Publishing Company. All rights reserved.


Vaseashta A.,Institute for Advanced Science Convergence
Materials Research Society Symposium Proceedings | Year: 2011

Paradigmatically, the convergence of science has exceptionally high potential for transforming the manner in which state-of-the-art information is gathered, analyzed, and leveraged to enable future advances and applications. Highlighting the potential and challenges of hierarchically integrating nanotechnologies is essential for realizing commercial applications. The heterogeneity of structures and compositions of nanomaterials present limitless possibilities; yet these envisioned benefits may be accompanied by certain technological limitations of integrating nanomaterials in commercial products. A balanced overview is presented of the realistic capabilities and potential, as well as the limitations, challenges of system engineering nanomaterials in platform integration. Examples of integrating nanomaterials in useable platforms are also presented. Most notably, the review suggests that nanomaterial based systems and devices that do not require a nano to micro/macro interface integration have reached commercialization whereas those needing a nano-to-micro/macro interface require further investigations. These selected studies provide an insight in obstacles and challenges presented by hierarchical integration of nanomaterials in commercial systems/devices and are crucial for commercialization as the research transitions from laboratory to marketplace, having the potential to transform into a multi-billion dollar niche market. © 2011 Materials Research Society.


Vaseashta A.,Institute for Advanced science Convergence | Braman E.,Institute for Advanced science Convergence | Susmann P.,Institute for Advanced science Convergence | Dekhtyar Y.,Riga Technical University | Perovicha K.,Riga Technical University
SAS 2011 - IEEE Sensors Applications Symposium, Proceedings | Year: 2011

Identification and analysis of contaminants arising from occasional release or intentional discharge in unsecured water supplies are fundamental to public welfare. This calls for national and international capacities to respond, sense, detect, isolate, and mitigate threats to water quality. Using advanced nanomaterials as enabling technologies, a series of novel point and stand-off sensors and detectors for continuous and in-situ monitoring of inorganic, organic, and microbiological pollutants are described. New sensing approaches based on interaction of the semiconductor surface using electron emission and metal complexes based chiroptical switches are also described. © 2011 IEEE.


Kavaz D.,Hacettepe University | Odabas S.,Hacettepe University | Denkbas E.B.,Hacettepe University | Vaseashta A.,Institute for Advanced science Convergence
Digest Journal of Nanomaterials and Biostructures | Year: 2012

The objective of this investigation is to develop a simple, rapid, and practical separation system for IgG separation using magnetic chitosan nanoparticles. Magnetic nanoparticles were prepared by co-precipitation method and coated with a biocompatible polymer chitosan by varying molecular weights. Morphological analyses of magnetic chitosan nanoparticles were investigated by Scanning Electron Microscope (SEM) and Zeta-Sizer. Chemical structure of the nanoparticles was analyzed by Fourier Transform Infra-Red Spectroscopy (FTIR) and magnetic properties were investigated using Electron Spin Resonance (ESR) and Vibrating Sample Magnetometer (VSM). For the purification of IgG, a well-known protein Concanavalin A (Con-A), having a strong affinity to the IgG molecules, was immobilized onto magnetic chitosan nanoparticles. IgG purification was performed using a batch separation system made locally. It was observed that IgG can easily be purified from fresh human plasma with high efficacy, using a simple and inexpensive system prepared locally. Nanoparticle size, IgG concentrations and the Con-A concentrations were investigated to get an optimum separation efficiency.


Enaki N.A.,Moldova Academy of Sciences | Turcan M.,Moldova Academy of Sciences | Vaseashta A.,Institute for Advanced science Convergence
NATO Science for Peace and Security Series A: Chemistry and Biology | Year: 2012

This study examines the coherence properties among the Stokes and anti- Stokes fields and their applications in Communications. We investigate a novel two-photon entangled sources approach which takes into account the coherence and collective phenomena between the fields. The quantum propriety of realistic sources of powerful coherent bi-boson radiation (coherent entanglement of Stokes and anti-Stokes photons) is analyzed. Finally, we examine experimental applications of coherence between the Stokes and anti-Stokes photons obtained in super-radiance and resulting lasing effects in quantum communications and cryptography. © 2012 Springer Science+Business Media B.V.


Mokdad R.,Mouloud Mammeri University | Benfdila A.,Mouloud Mammeri University | Vaseashta A.,Institute for Advanced science Convergence
Journal of Optoelectronics and Advanced Materials | Year: 2011

The present work deals with the study a symmetric structure response generating a plasmons polariton of long range using a simplified geometrical structure consisting on a gold thin film set between two layers of PMMA. Surface plasmons are considered as typical mode of the metal-dielectric interface. This aims an optimization of the parameters affecting the surface plasmons ranges, such as the multilayer structure thickness, incidence angle and the wave length.

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