Aboonq M.S.,Taibah University
Neurosciences | Year: 2015
Carpal tunnel syndrome (CTS) is the most common median nerve neuropathy, accounting for 90% of all neuropathies. Carpal tunnel syndrome presents in 3.8% of the general population, with a higher prevalence among women. There are several risk factors associated with CTS, including both medical and non medical factors. The pathophysiologic mechanisms involved in the median nerve compression and traction are thought to be complex, and as yet are not fully understood. The present review aimed to provide an overview of the pathophysiology of median nerve neuropathy in the carpal tunnel, and subsequent development of CTS. © 2015, Saudi Arabian Armed Forces Hospital. All rights reserved.
Alginahi Y.M.,Taibah University
International Journal on Document Analysis and Recognition | Year: 2013
Arabic character segmentation is a necessary step in Arabic Optical Character Recognition (OCR). The cursive nature of Arabic script poses challenging problems in Arabic character recognition; however, incorrectly segmented characters will cause misclassifications of characters which in turn may lead to wrong results. Therefore, off-line Arabic character segmentation is a difficult research problem and little research has been achieved in this area in the past few decades. This is due to both the cursive nature of Arabic writing in both printed and handwritten forms and the scarcity of Arabic databases and dictionaries. Most of the character recognition methods used in the recognition of Arabic characters are adopted from available methods used on handwritten Latin and Chinese characters; however, other methods are developed only for Arabic character segmentation. This survey presents the description of the Arabic script characteristics with an overview on OCR systems and a comprehensive review mainly on off-line printed Arabic character segmentation techniques. © 2012 Springer-Verlag.
Basit S.,Taibah University
British Journal of Biomedical Science | Year: 2013
Vitamin D, a fat-soluble prohormone, is synthesised in response to sunlight. Vitamin D requires two metabolic conversions, 25-hydroxylation in the liver and 1α-hydroxylation in the kidney, to become active hormone. The active form, 1α,25-(OH)2D, binds to the vitamin D receptor (VDR) to modulate gene transcription and regulate mineral ion homeostasis. Vitamin D plays several roles in the body, influencing bone health as well as serum calcium and phosphate levels. Furthermore, vitamin D may modify immune function, cell proliferation, differentiation and apoptosis. Vitamin D deficiency has been associated with numerous health outcomes, including risk of rickets in children or osteomalacia in adults, increased risk of fractures, falls, cancer, autoimmune disease, infectious disease, type 1 and type 2 diabetes, hypertension and heart disease, and other diseases such as multiple sclerosis. Here, vitamin D physiology and metabolism, its genomic action and association of polymorphisms in vitamin D pathway genes with different diseases are reviewed by focusing on new findings published in the literature.
Benghanem M.,Taibah University
Applied Energy | Year: 2011
This article analyzes the optimal choice of the tilt angle for the solar panel in order to collect the maximum solar irradiation. In this paper, the collector surface is assumed to be facing toward equator. The study is based upon the measured values of daily global and diffuse solar radiation on a horizontal surface. It is shown that the optimal angle of tilt (βopt) for each month, allows us to collected the maximum solar energy for Madinah site. Annual optimum tilt angle is found to be approximately equal to latitude of the location. It is found that the loss in the amount of collected energy when using the yearly average fixed angle is around 8% compared with the monthly optimum tilt βopt. © 2010 Elsevier Ltd.
Benghanem M.,Taibah University
Renewable Energy | Year: 2010
In this paper, the development of wireless data acquisition system (WDAS) for weather station monitoring is described. It is based on the Emitter/Receiver architecture and it does not require the physical connection of the monitored systems to the data collection server. The proposed system consists of a set of sensors for measuring meteorological parameters (solar radiation, temperature, humidity, pressure, wind speed & direction, rain fall, etc.). The collected data are first conditioned using precision electronic circuits and then interfaced to a PC using RS232 connection via wireless unit. The LabVIEW program is used to further process, display and store the collected data in the PC disk. The proposed architecture permits the rapid system development and has the advantage of flexibility and it can be easily extended for controlling the renewable energy systems like photovoltaic system. The measured parameters are available on-line over the internet to any user. © 2009 Elsevier Ltd. All rights reserved.
Kooli F.,Taibah University
Microporous and Mesoporous Materials | Year: 2014
The conventional method of synthesizing porous clay heterostructures (PCHs) is based on the use of cetyltrimethylammonium cations, amines (as a co-surfactant) and a silica source. In the present study, we report the preparation of PCH materials from Al13-intercalated montmorillonite and its pillared derivatives using one directing template (dodecylamine) and a silica source. This method allowed us to reduce the use of the organic template and to incorporate the aluminum species directly into the silica framework intercalated between the clay sheets in one step. The dodecylamine template was removed by calcination at 550 C in air. The PCH material prepared from the Al13-intercalated clay exhibited a higher surface area, mesopore volume and acidity, as well as strong Brønsted and Lewis acid sites. However, the use of pillared clays did not lead to the formation of PCH material due to the strong interaction between the alumina species and the clay sheets, which hindered their exchange with dodecylamine, as indicated by XRD and 29Si and 27Al solid-state NMR techniques. The hydro-isomerization reaction of heptane was tested on the differently prepared PCHs with a conversion of 60% and isomer yield of 50% at 350 C. © 2013 Elsevier Inc. All rights reserved.
Messali M.,Taibah University
Arabian Journal of Chemistry | Year: 2015
A facile preparation of a series of 17 new functionalized picolinium-based ionic liquids under "green chemistry" conditions is described. For the first time, target ionic liquids were prepared using standard methodology and under microwave irradiation in short duration of time with quantitative yields. Their structures were characterized by FT-IR, 1H NMR, 13C NMR, 11B, 19F, 31P and mass spectra. © 2011.
Dawoud Bani-Yaseen A.,Taibah University
Journal of Luminescence | Year: 2011
The interaction between the antimicrobial drug sulfamethazine (STM) and bovine serum albumin (BSA) has been studied using steady state and synchronous fluorescence spectroscopy. Fluorescence emission data revealed that BSA (2×10-6 M) fluorescence was statically quenched by STM at various concentrations, which implies that STMBSA complex has been formed. The fluorescence emission data was analyzed via applying the SternVolmer analysis in combination with thermodynamic investigation, where obtained results revealed that quenching is static with quenching constants of 2.371, 1.658, and 0.916×105 M-1 at 298, 304, and 310 K, respectively. Binding constants and number of binding sites at different temperatures were also determined by applying the Scatchard method, which in turn were used to construct the vant Hoff plot in order to estimate the enthalpy (ΔH) and entropy changes (ΔS) for the complexation process. An average of 1.00±0.17 was estimated for the number of sites of BSA, which indicated that STM binds to BSA with stoichiometric ratio of 1:1. The values that were estimated from the vant Hoff plot for ΔH and (ΔS) were -36.8 kJ mol-1 and -14.9 J mol-1 K-1, respectively, which indicate that the STMBSA complex is stabilized with hydrogen bonds and van der Waals interactions. Synchronous fluorescence data was obtained at Δλ of 15 and 60 nm, where obtained results confirmed that STM binds to BSA at the tryptophan residue (Trp. 213). In addition, the distance between STM and the Trp. 213 was estimated via employing the Frsters non-radiative energy-transfer theory, and was found to be 2.73 nm, which in turn indicated that STM can bind to BSA with high probability. © 2010 Elsevier B.V. All rights reserved.
Ghanem B.S.,Taibah University
Polymer Chemistry | Year: 2012
A new synthetic approach affords the first example of a triptycene-containing A-B monomer bearing both phenazine activating aromatic o-dichloride and a catechol group which can be used for the synthesis of a novel polymer of intrinsic microporosity (PIM) has been developed. The new polymer was characterized by GPC, IR, and 1H NMR, elemental analysis and demonstrated good porosity, thermal stability and solubility in common organic solvents such as chloroform from which a self-supporting and transparent film could be cast.
Taibah University | Date: 2014-01-09
This invention relates to precursors of the molybdenum-containing materials such as molybdenum trioxide MoO3. These precursors can be used to prepare polymetallic oxides materials varying metals proportions or they can be used for composite phases as well. Moreover, these precursors are highly soluble in polar solvents as the water or alcohols. It follows their potential to also obtain materials containing molybdenum as thin films. These precursors are obtained by solid state reaction of polycarboxylic acids and ammonium molybdate (NH4)6Mo7O24.4H2O.