King Saud UniversityRiyadh

King, Saudi Arabia

King Saud UniversityRiyadh

King, Saudi Arabia
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Nithyadevi N.,Bharathiar University | Begum A.S.,Bharathiar University | Oztop H.F.,Firat University | Al-Salem K.,King Saud UniversityRiyadh
International Journal of Heat and Mass Transfer | Year: 2017

Inclination angle effects on mixed convection heat transfer in a rectangular porous enclosure filled by Cu-water nanofluid have been numerically analyzed in the present study. Boundary of the enclosure has sinusoidal heating vertical walls, adiabatic horizontal walls and the heated mid-horizontal moving wall. Control volume method is used to discretize the nonlinear governing differential equations. Richardson number (Ri) from 0.01 to 100, Darcy number (Da) from 10−3 to 10−5, inclination angle (γ) from 0° to 90°, solid volume fraction of nanoparticle (φ) from 0.0 to 0.2 and porosity (ε) of the porous medium from 0.4 to 0.8 are discussed and portrayed in the form of streamlines, isotherms, average Nusselt number and velocity graphs. It is observed that the governing flow parameters has significant impact on the fluid flow and temperature distributions. In particular, the features of enclosure inclination, presence of copper nanoparticles in the fluid-saturated porous media and inserting moving wall at the centre of the enclosure are found to enhance the heat transfer rate. © 2016

Ahmad J.,King College | Ahmad J.,King Saud UniversityRiyadh | Alhadlaq H.A.,King Saud UniversityRiyadh | Alhadlaq H.A.,King College | And 14 more authors.
Journal of Applied Toxicology | Year: 2016

Copper ferrite nanoparticles (NPs) have the potential to be applied in biomedical fields such as cell labeling and hyperthermia. However, there is a lack of information concerning the toxicity of copper ferrite NPs. We explored the cytotoxic potential of copper ferrite NPs in human lung (A549) and liver (HepG2) cells. Copper ferrite NPs were crystalline and almost spherically shaped with an average diameter of 35 nm. Copper ferrite NPs induced dose-dependent cytotoxicity in both types of cells, evident by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide and neutral red uptake assays. However, we observed a quite different susceptibility in the two kinds of cells regarding toxicity of copper ferrite NPs. Particularly, A549 cells showed higher susceptibility against copper ferrite NP exposure than those of HepG2 cells. Loss of mitochondrial membrane potential due to copper ferrite NP exposure was observed. The mRNA level as well as activity of caspase-3 enzyme was higher in cells exposed to copper ferrite NPs. Cellular redox status was disturbed as indicated by induction of reactive oxygen species (oxidant) generation and depletion of the glutathione (antioxidant) level. Moreover, cytotoxicity induced by copper ferrite NPs was efficiently prevented by N-acetylcysteine treatment, which suggests that reactive oxygen species generation might be one of the possible mechanisms of cytotoxicity caused by copper ferrite NPs. To the best of our knowledge, this is the first report showing the cytotoxic potential of copper ferrite NPs in human cells. This study warrants further investigation to explore the mechanisms of differential toxicity of copper ferrite NPs in different types of cells. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Yager R.R.,The College of New Rochelle | Yager R.R.,King Saud UniversityRiyadh | Alajlan N.,KING.INFO
Information Sciences | Year: 2016

The basic features and properties of a fuzzy measure are first introduced. We next discuss the Choquet integral and describe its usage in finding the aggregation of a collection of values guided by a fuzzy measure. We then show how the Choquet integral and an associated fuzzy measure can be applied to the construction of multi-criteria decision functions and describe how the associated fuzzy measure is used to model the desired multi-criteria decision function. We then look at various fuzzy measures and investigate the types of decision functions they allow us to formulate. Notable among the measures investigated here are those that allow us to model a prioritized aggregation of the criteria and a rule based aggregation of multiple criteria. Finally we show how to model linguistically specified decision functions using fuzzy measures. © 2016 Elsevier Inc.

Yager R.R.,The College of New Rochelle | Yager R.R.,King Saud UniversityRiyadh | Alajlan N.,KING.INFO
Knowledge-Based Systems | Year: 2015

We are concerned with the problem of obtaining a consensus subjective probability distribution from the individual opinions of a group of agents about the subjective probability distribution. We provide an iterative interactive algorithm that allows the agents to come to consensus formulation for the subjective probability distribution. © 2015 Elsevier B.V. All rights reserved.

Choi C.,Korea UniversitySeoul | Seo S.-D.,Korea UniversitySeoul | Shim H.-W.,Korea UniversitySeoul | Dar M.A.,King Saud UniversityRiyadh | And 2 more authors.
Journal of Alloys and Compounds | Year: 2015

The synthesis of materials with ordered or self-assembled superstructures provides opportunities to tune the material's physical and chemical properties for energy storage device applications. Here, we report the synthesis of a three-dimensional (3-D) hierarchical cobalt orthophosphate (Co3(PO4)2) compound by a facile wet-chemical route at a low temperature (65 °C), followed by a dehydration process (600 °C). The resulting cobalt orthophosphate compounds were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and thermogravimetric (TG)/differential thermal analysis (DTA). The compounds' electrochemical behavior for lithium-ion batteries was also investigated. Analysis revealed the flower-like microarchitecture of the cobalt orthophosphate compound, in which porous nano-plates with an average thickness of 150 nm were self-assembled into a microscale superstructure. As an anode material for lithium-ion batteries, the optimal cobalt orthophosphate compound showed stable cycle performance (0.083% capacity decay per cycle over 100 cycles). © 2015 Elsevier B.V.

Khan A.A.,King College | Al Kheraif A.A.,King College | Alhijji S.M.,King College | Matinlinna J.P.,University of Hong Kong | Matinlinna J.P.,King Saud UniversityRiyadh
International Journal of Adhesion and Adhesives | Year: 2016

Aim The objective of this laboratory study was to analyze the effect of different grit-blasting pressures on adhesion of resin to silica-coated and silanized Ti using the shear bond test. Materials and methods A total of 24 commercially pure grade 2 Ti coupons (1 mm×20 mm×40 mm) were prepared and randomly assigned to 4 groups based on surface treatment: 150 kPa grit-blasting pressure with Rocatec™ Soft (group 1) for 10 s. Similarly, groups 2, 3 and 4 were treated at 280 kPa (control), 330 kPa and 380 kPa grit-blasting pressures, respectively, and followed by silanization. A total of 10 resin stubs per group were bonded onto each treated surface with photopolymerization. The shear bond strength was measured after 24 h dry storage in a desiccator, 2 months H2O storage, and 4 months H2O storage. Data were analyzed using descriptive statistics and two-way ANOVA (p<0.05). Results After 24 h, initial SBS values of tested groups were significantly higher (32.0% for group 1, 39.1% for group 3, and 23.9% for group 4) than the control (group 2). After artificial aging, SBS values decreased in all the groups. The highest adhesion strength was seen in 150 kPa (13.0±3.0) and 280 kPa (4.9±2.4) after 2 months, and 4 months artificial aging, respectively. Conclusion A lower grit-blasting pressure might promote adhesion strength in long term water aging. © 2015 Elsevier Ltd.

PubMed | Sri Guru Granth Sahib World University, King Saud UniversityRiyadh, Guru Nanak Dev University and University of the Humanities
Type: | Journal: Frontiers in plant science | Year: 2016

The present experiment was designed to assess the effects of seed soaking with 24-epibrassinolide (EBR) on the physiology of

Ben Ghanem O.,Petronas University of Technology | Mutalib M.I.A.,Petronas University of Technology | Leveique J.-M.,Petronas University of Technology | Gonfa G.,Petronas University of Technology | And 2 more authors.
Journal of Chemical and Engineering Data | Year: 2015

A series of new synthesized ionic liquids based on 1-octyl-3-methylimidazolium with glycinate, alaninate, serinate, prolinate, and asparaginate anions were prepared. Their thermophysical properties (density, viscosity, surface tension, and heat capacity) were measured at various temperatures and atmospheric pressures. Physicochemical properties such as thermal expansion coefficient values, molecular volume, standard molar entropy, and lattice energy standard were also determined using empirical methods. The effects of anions on the studied properties were further analyzed. © 2015 American Chemical Society.

PubMed | South Valley UniversityQena, King Saud UniversityRiyadh, Jamia Hamdard University, Government College University at Faisalabad and Near East University
Type: | Journal: Frontiers in plant science | Year: 2016

Plants often experience various biotic and abiotic stresses during their life cycle. The abiotic stresses include mainly drought, salt, temperature (low/high), flooding and nutritional deficiency/excess which hamper crop growth and yield to a great extent. In view of a projection 50% of the crop loss is attributable to abiotic stresses. However, abiotic stresses cause a myriad of changes in physiological, molecular and biochemical processes operating in plants. It is now widely reported that several proteins respond to these stresses at pre- and post-transcriptional and translational levels. By knowing the role of these stress inducible proteins, it would be easy to comprehensively expound the processes of stress tolerance in plants. The proteomics study offers a new approach to discover proteins and pathways associated with crop physiological and stress responses. Thus, studying the plants at proteomic levels could help understand the pathways involved in stress tolerance. Furthermore, improving the understanding of the identified key metabolic proteins involved in tolerance can be implemented into biotechnological applications, regarding recombinant/transgenic formation. Additionally, the investigation of identified metabolic processes ultimately supports the development of antistress strategies. In this review, we discussed the role of proteomics in crop stress tolerance. We also discussed different abiotic stresses and their effects on plants, particularly with reference to stress-induced expression of proteins, and how proteomics could act as vital biotechnological tools for improving stress tolerance in plants.

Al-Qattan M.M.,King Saud UniversityRiyadh | Kfoury H.,King Saud UniversityRiyadh
Journal of Hand Surgery | Year: 2015

We report a patient who developed a delayed hypersensitivity reaction to a polypropylene suture used in flexor pollicis longus repair. We also review the literature and aim to increase the awareness of hand surgeons to the presentation, diagnosis, and management of these rare cases. © 2015 American Society for Surgery of the Hand.

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