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Ali Abuhasel K.,Prince Sattam bin Abdulaziz University
Jurnal Teknologi | Year: 2016

Purification system has recently gained increasing importance, especially in water treatment systems. Biological water treatment systems with microalgae are now widely accepted. Moreover, algal wastewater treatment systems are effective when compared to conventional treatment systems. The proposed purification system aims to provide a process for using saline water, and saline reject water produced in water purification for gold mining production. Also, it provides a method for growing and harvesting algae utilizing saline water as growth medium for recycling waste water to extract the remaining metals from it. This trend of purification system using harvested algae has various applications, and may be used in wide aspects including, but not limited to, algae biomass production to extract metals, and reducing the cost of gold mining production. © 2016 Penerbit UTM Press. All rights reserved.

Ahmad S.,Prince Sattam bin Abdulaziz University
British Journal of Biomedical Science | Year: 2015

This study aims to determine the asymptomatic bacteriuria in pregnancy due to GBS and its antimicrobial sensitivity pattern for planning strategy for the management of these cases and also to determine the relationship between asymptomatic bacteriuria and pyuria. A total of 3863 consecutive urine specimens were collected from 3863 pregnant women with asymptomatic bacteriuria attending the obstetrics and gynaecology department of our hospital over a period of two years. Specimens were processed using standard microbiological procedures. All the subjects were evaluated for bacteriuria. The prevalence of asymptomatic bacteriuria due to group B streptococci (GBS) was 82/3863 (2.1%) among pregnant women in Saudi Arabia. Among these, 69/82 patients (84.2%) had clinical and microbiological features consistent with cystitis, versus 13/82 (15.8%) for pyelonephritis. About 51.2% (42/82) of the patients who had urine analysis performed had positive results based on positive urinary leucocyte esterase and pyuria. Disc-diffusion analysis of all 82 GBS isolates showed that they were highly susceptible to Augmentin and linezolid. Screening for bacteriuria in pregnancy and proper treatment must be considered as an essential part of antenatal care in this community. To prevent asymptomatic bacteriuria complications, all pregnant women should be screened at the first antenatal visit. A negative test for pyuria is not a reliable indicator of the absence of asymptomatic bacteriuria in pregnant women. Further, ongoing surveillance and evaluation of outcomes in pregnancies complicated by GBS bacteriuria is required to optimise maternal and newborn care.

Al Yahya R.S.,Prince Sattam bin Abdulaziz University
Lasers in Medical Science | Year: 2016

Primary cutaneous amyloidosis (PCA) is a condition characterized by tissue deposition of misfolded proteins. PCA can present in different forms, namely macular, lichen, and nodular amyloidosis. These lesions can be of cosmetic concern and are difficult to treat. Many therapeutic modalities have been suggested for the treatment of PCA, with variable efficacy, including topical and systemic medications, phototherapy, electrodessication, dermabrasion, cryosurgery, and lasers. Over the past decade, several studies have reported successful treatment of PCA with different types of lasers; however, a review of these studies has never been reported in the dermatologic literature. The aim of this study was to review the efficacy and safety of lasers in the treatment of PCA. A search of the National Library of Medicine’s PubMed Database was performed. Studies were considered for inclusion based on their relevance, and specific data were extracted from all included studies. Eleven studies, comprising 64 patients, were included in this review. Significant improvements were observed in macular and lichen amyloidosis patients treated with carbon dioxide laser in two studies, while a number of case series and case reports showed good results with other types of laser in the treatment of PCA. This review was limited by the lack of large double-blinded randomized controlled trials and the overall small sample size. Laser treatment is a promising option in the treatment of PCA. Future randomized controlled trials are needed to compare the efficacy of different types of lasers and to select the best parameters for different types of PCA. © 2016, Springer-Verlag London.

Density functional theory has been implemented to study the electronic structure, molecular properties and vibrational spectra of 3-(adamantan-1-yl)-4-(4-chlorophenyl)-1H-1,2,4-triazole-5(4H)-thione, a novel 1,2,4-triazole-5(4H)-thione derivative. Hydrogen bonded dimer of the title molecule has been studied using B3LYP, M06-2X and X3LYP functionals at 6-311++ G(d,p) level of theory. The intermolecular hydrogen bonding has been studied using NBO analysis of the dimer. Bader's AIM theory was also used to evaluate the strength as well as the hydrogen bonding characteristics. Experimental FT-IR and FT-Raman spectra of the title molecule were related with the spectral data obtained with DFT/B3LYP method. The 1H NMR chemical shifts of the title molecule were calculated by the GIAO method and compared with experimental results. Dipole moment, polarizability (α), first order static hyperpolarizability (β) along with molecular electrostatic potential surface have been calculated. Frequency-dependent first hyperpolarizabilities, β(-2ω;ω,ω) and β(-ω;ω,0) have also been evaluated to study the non-linear optical behavior of the title compound. UV-Vis spectrum of the title molecule was recorded and TD-DFT method has been used to calculate six lowest excited states and the corresponding excitation energies. © 2016 Elsevier B.V. All rights reserved.

El-Sousy F.F.M.,Prince Sattam bin Abdulaziz University | El-Sousy F.F.M.,Electronics Research Institute of Egypt
Applied Soft Computing Journal | Year: 2016

In this paper, an intelligent adaptive tracking control system (IATCS) based on the mixed H2/H∞ approach under uncertain plant parameters and external disturbances for achieving high precision performance of a two-axis motion control system is proposed. The two-axis motion control system is an X-Y table driven by two permanent-magnet linear synchronous motors (PMLSMs) servo drives. The proposed control scheme incorporates a mixed H2/H∞ controller, a self-organizing recurrent fuzzy-wavelet-neural-network controller (SORFWNNC) and a robust controller. The combinations of these control methods would insure the stability, robustness, optimality, overcome the uncertainties, and performance properties of the two-axis motion control system. The SORFWNNC is used as the main tracking controller to adaptively estimate an unknown nonlinear dynamic function that includes the lumped parameter uncertainties, external disturbances, cross-coupled interference and frictional force. Moreover, the structure and the parameter learning phases of the SORFWNNC are performed concurrently and online. Furthermore, a robust controller is designed to deal with the uncertainties, including the approximation error, optimal parameter vectors and higher order terms in Taylor series. Besides, the mixed H2/H∞ controller is designed such that the quadratic cost function is minimized and the worst case effect of the unknown nonlinear dynamic function on the tracking error must be attenuated below a desired attenuation level. The mixed H2/H∞ control design has the advantage of both H2 optimal control performance and H∞ robust control performance. The sufficient conditions are developed for the adaptive mixed H2/H∞ tracking problem in terms of a pair of coupled algebraic equations instead of coupled nonlinear differential equations. The coupled algebraic equations can be solved analytically. The online adaptive control laws are derived based on Lyapunov theorem and the mixed H2/H∞ tracking performance so that the stability of the proposed IATCS can be guaranteed. Furthermore, the control algorithms are implemented in a DSP-based control computer. From the experimental results, the motions at X-axis and Y-axis are controlled separately, and the dynamic behaviors of the proposed IATCS can achieve favorable tracking performance and are robust to parameter uncertainties. © 2015 Elsevier B.V. All rights reserved.

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