Hydrophobic Cross-Linked Poly(dimethylsiloxane)-Based Sorbents for Oil Spill Applications

With the increase of industrialization and urbanization, humankind faces massive oil-based pollution due to tanker accidents, human error, and natural disasters. For this, hydrophobic sorbents are fabricated and their applications for the removal of oil from polluted water sources are investigated. These hydrophobic sorbents are prepared by the condensation reaction of poly(dimethylsiloxane) and tris[3-(trimethoxysilyl)propyl]isocyanurate cross-linker via bulk polymerization. The obtained sorbents exhibit high oil sorption capacity, fast absorption–desorption kinetics, and great reusability. Moreover, they can selectively absorb oil from the water surface, thus making them practical for water clean-up applications.     

The Evolving Role of Fetuin-A in Nonalcoholic Fatty Liver Disease: An Overview from Liver to the Heart

Nonalcoholic fatty liver disease (NAFLD) is strongly associated to the features of metabolic syndrome which can progress to cirrhosis, liver failure and hepatocellular carcinoma. However, the most common cause of mortality in people with NAFLD is not liver-related but stems from atherosclerotic cardiovascular disease (CVD). The prevalence of NAFLD is on the rise, mainly as a consequence of its close association with two major worldwide epidemics, obesity and type 2 diabetes (T2D). The exact pathogenesis of NAFLD and especially the mechanisms leading to disease progression and CVD have not been completely elucidated. Human fetuin-A (alpha-2-Heremans Schmid glycoprotein), a glycoprotein produced by the liver and abundantly secreted into the circulation appears to play a role in insulin resistance, metabolic syndrome and inflammation. This review discusses the links between NAFLD and CVD by specifically focusing on fetuin-A’s function in the pathogenesis of NAFLD and atherosclerotic CVD.     

Using an artificial bee colony algorithm for the optimal placement of viscous dampers in planar building frames

In this study, an Artificial Bee Colony Algorithm (ABCA) is used to obtain the optimal size and location of viscous dampers in planar buildings to reduce the damage to the frame systems during an earthquake. The transfer function amplitude of the top displacement and the elastic base shear force evaluated at the first natural circular frequency of structures are chosen as objective functions. The damper coefficients of the added viscous dampers are taken into consideration as design variables in a planar building frame. Transfer function amplitude of the top displacement and the amplitude of the elastic base shear force at the fundamental natural frequency are minimized under an active constraint on sum of the damper coefficients of the added dampers. According to two specified objective functions, an optimization algorithm based on the ABCA is proposed. The proposed method is verified by a gradient-based algorithm; steepest direction search algorithm (SDSA). The proposed ABCA and the SDSA are applied to find the optimal damper distribution for a nine-storey planar building then the optimal damper allocation obtained from the ABCA is investigated to rehabilitate models of irregular planar buildings. The validity of the proposed method was demonstrated through a time history analysis of the optimal damper designs, which were determined based on the frequency domain using the ABCA. The numerical results of the proposed optimal damper design method show that the use of the ABCA can be a practical and powerful tool to determine the optimal damper allocation in planar building structures.     

Development of a technology mentor survey instrument: Understanding student mentors’ benefits

Agreement on the effectiveness of the technology mentoring approach in addressing educators’ needs for learning different technologies has been growing. Literature on the concept of mentoring in general and technology mentoring specifically has indicated mentoring relationships in different settings provide benefits for the less experienced mentoring partner, while existing literature was limited in providing insights about mentoring from the more experienced partner’s point of view. But, studies have suggested that understanding mentors’ reactions to the experience is necessary to establish sustainable and mutually beneficial mentoring relationships. For this purpose, this study discusses and proposes an assessment framework and an instrument to examine benefits for technology mentors. Considering the lack of similar studies and the absence of an instrument designed specifically to study this subject, we believe that our study will contribute to the knowledge base by providing educators with an assessment strategy and a tool for investigating the benefits gained by the more experienced person (graduate student in our context) benefits in a technology mentoring relationship. In addition, the resulting survey instrument provided along with this study is a valuable tool for those studying technology mentoring. The theoretical foundations, development process of the development of the instrument, and reliability and validity issues are discussed in detail.     

Data transformation in the evidential reasoning-based decision making process

This paper describes the application of an evidential reasoning (ER)‐based decision making process to multiple‐criteria decision making (MCDM) problems having both quantitative and qualitative criteria. The ER approach is based on the decision theory and the theory of evidence and it uses the concept of ‘degree of belief’ to assess decision alternatives on each attribute. When faced with MCDM problems, evaluation and selection or ranking of alternatives appear to be both challenging and vital to arrive at a rational and robust decision. In the presence of both qualitative and quantitative evaluations in an MCDM problem, it is necessary, when using the ER‐based decision making process, to transform or convert quantitative data into a belief structure using a number of grades so that the converted belief structure and the original quantitative data are equivalent in values or utilities. This paper suggests three scenarios for data transformation and examines how the ranking of decision alternatives is changed when different scenarios of data transformation are used. Ranking of UK universities using the ER approach is illustrated as an example.     

Organic solvent absorbents based on linear diol

Cross‐linked poly(orthocarbonate)s were prepared by condensation of the tetraethyl orthocarbonate with different length of aliphatic diols. The synthesized polymers have been characterized by Fourier‐transform infrared spectroscopy, solid‐state ¹³C cross‐polarization magic angle spinning (CPMAS) nuclear magnetic resonance, thermal gravimetric analysis, and elemental analysis. The cross‐linked polymers were evaluated for organic solvent absorbency application. The effect of diol type on swelling properties of cross‐linked polymers was studied through the solvent absorption tests. The swelling parameters such as maximum solvent absorbency, saturation time, and retention of the solvent were evaluated for the synthesized sorbents. All of the cross‐linked polymers had moderate thermal stability and good regenerable solvent uptake abilities. POLYM. ENG. SCI., 53:2102–2108, 2013. © 2013 Society of Plastics Engineers     

Performance of joint multilevel/AES‐LDPCC‐CPFSK schemes over wireless sensor networks

In wireless sensor networks, data encryption and channel coding are considered together for ensuring secure and robust communication. In order to achieve this purpose, we introduce a new joint scheme, namely ‘Multilevel/Advanced Encryption Standard‐Low Density Parity Check Coded‐Continuous Phase Frequency Shift Keying (ML/AES‐LDPCC‐CPFSK)’. AES algorithm is the most powerful and widely used symmetric key cryptography in providing secure data transmission. LDPC codes have very large Euclidean distance and use iterative decoding algorithms. In this study, we have increased error performance employing multilevel structure to AES and LDPC. In all communications systems, phase discontinuities of modulated signals result in extra bandwidth requirements. CPFSK, which is a special type of continuous phase modulation, is a powerful solution for this problem. In this paper, we simulate error performance of ML/AES‐LDPCC‐CPFSK for regular LDPC codes. Simulation results are drawn for 4CPFSK, 8CPFSK and 16CPFSK over wireless cooperative sensor networks. Using this scheme, we are able to improve bit error performance, channel throughput, security level of communication and reduction in complexity compared with related schemes such as various turbo code structures. Copyright © 2009 John Wiley & Sons, Ltd.