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Search Results: 1 - 10 of 5619 matches for " Omar Saleh "
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Method of Designing Generators of Pseudorandom Sequences for Information Protection Based on Shift Register with Non-Linear Feedback Function  [PDF]
Saleh Al-Omar
Journal of Information Security (JIS) , 2014, DOI: 10.4236/jis.2014.54020
Abstract: This paper proposes an efficient, high-tech method of construction of pseudorandom binary sequences generators with a repetition period 2n for n-bit shift register with a nonlinear feedback function. The developed method is illustrated by constructing a nonlinear function feedback shift register. It is proved that the offered method requires the realization of a memory size proportional to n2 that allows making successful use of suitable generators for practical use on the shift register of the longer word.
Burst Error Correction Method Based on Arithmetic Weighted Checksums  [PDF]
Saleh Al-Omar, Atef Obeidat
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.411098
Abstract: In this paper a new approach for increasing the performance of burst error correction that occurs during data transmission in low-frequency channels with pulse-code modulation is proposed. The specific technique is based on the weighted checksum which is computed with arithmetic operations. It is shown that the solution proposed not only guarantees the correction of any single error burst but it also lowers the computational complexity so that procedure correction time does not depend on controlled data block length. Finally, the use of the algorithm is illustrated via the thorough presentation of an example of erroneous data transmission.
EXPOSURE OF DENTAL PERSONNEL TO NITROUS OXIDE
Omar Saleh Mustafa
e-Journal of Dentistry , 2012,
Abstract:
DNA Unwinding by Ring-Shaped T4 Helicase gp41 Is Hindered by Tension on the Occluded Strand
Noah Ribeck, Omar A. Saleh
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0079237
Abstract: The replicative helicase for bacteriophage T4 is gp41, which is a ring-shaped hexameric motor protein that achieves unwinding of dsDNA by translocating along one strand of ssDNA while forcing the opposite strand to the outside of the ring. While much study has been dedicated to the mechanism of binding and translocation along the ssDNA strand encircled by ring-shaped helicases, relatively little is known about the nature of the interaction with the opposite, ‘occluded’ strand. Here, we investigate the interplay between the bacteriophage T4 helicase gp41 and the ss/dsDNA fork by measuring, at the single-molecule level, DNA unwinding events on stretched DNA tethers in multiple geometries. We find that gp41 activity is significantly dependent on the geometry and tension of the occluded strand, suggesting an interaction between gp41 and the occluded strand that stimulates the helicase. However, the geometry dependence of gp41 activity is the opposite of that found previously for the E. coli hexameric helicase DnaB. Namely, tension applied between the occluded strand and dsDNA stem inhibits unwinding activity by gp41, while tension pulling apart the two ssDNA tails does not hinder its activity. This implies a distinct variation in helicase-occluded strand interactions among superfamily IV helicases, and we propose a speculative model for this interaction that is consistent with both the data presented here on gp41 and the data that had been previously reported for DnaB.
Giant Calcified Renal Artery Aneurysm: Traditional RX versus Three-Dimensional Computed Tomography  [PDF]
Mauro Gacci, Omar Saleh, Annalisa Mantella, Leonidas Azas, Paola Romagnani, Andrea Minervini, Sergio Serni, Marco Carini
Advances in Computed Tomography (ACT) , 2013, DOI: 10.4236/act.2013.21004
Abstract: A 65-year-old woman with no history of previous flank trauma, renal stone or upper urinary tract infections, presented for flank pain and left hydro-uretero-nephrosis seven days after hysterectomy. Percutaneous pielography revealed narowing of the distal ureter, without endoureteral mass. The plain abdomen film incidentally showed a 3-cm calcified ring on the left renal shadow, who resulted external to the collecting system at pielography. A 3-dimensional-CT scan with angiographic reconstruction revealed a 3-cm calcified renal artery aneurysm. The vascular surgeon suggested a watchful waiting. The patient underwent ureteral reimplantation with ureteral stenting, allowing a complete recovery of iatrogenic stenosis two months postoperatively.
Spectrophotometric determination of some calcium channel blockers using Sulfochlorophenol-S, Bromopyrogallol red, Eriochromecyanine-R and Pyrocatechoil violet  [PDF]
Mahmoud A. Omar, Osama H. Abdelmageed, Ahmed A. Abdelgaber, Safaa F. Saleh
Natural Science (NS) , 2013, DOI: 10.4236/ns.2013.54065
Abstract:

Four simple, sensitive and accurate spectrophotometric methods have been developed for the determination of some calcium channel blockers: Amlodipine besylate (ADB), Diltiazem hydrochloride (DTZ) and Verapamil hydrochloride (VPM) in pharmaceutical formulations. These methods based on formation ion pair complexes with Sulfochlorophenol-S (SCPS), Bromopyrogallol red (BPR), Eriochromecyanine- R (ECC) and Pyrocatechol violet (PCV) in acidic medium. The colored products are extracted with chloroform and measured spectrophoto- metrically at 462, 600, 440 and 442 for ECC, SCPS, BPR and PCV, respectively. Beer’s low was obeyed in the concentration range, for ECC: 25 - 175 μg·ml-1, 50 - 150 μg·ml-1 or 100 - 250 μg·ml-1, for SCPS: 300 - 800 μg·ml-1, 200 - 700 μg·ml-1 or 100 - 550 μg·ml-1, for BPR: 50 - 400 μg·ml-1, 200 - 700 μg·ml-1 or 200 - 700 μg·ml-1 for VPM, DTZ or ADB, respectively and for PCV: 50 - 250 μg·ml-1 for VPM or 200 - 500 μg·ml-1 for DTZ with molar absorptivity, for ECC: 2.2 × 104, 2.1 × 104, 1.6 × 104 L·mol-1·cm-1, for SCPS: 3.8 × 103, 5.6 × 103, 8.1 × 103 L·mol-1·cm-1, for BPR: 11 × 103, 4.8 × 103, 6.9 × 103 L·mol-1·cm-1 for VPM, DTZ or ADB, respectively and for PCV: 19.5 × 103 L·mol-1·cm-1 for VPM and 6.6 ×

The 19 kDa Protein from Mycobacterium avium subspecies paratuberculosis Is a Glycolipoprotein  [PDF]
Saleh A. Naser, Saisathya Thanigachalam, Natalia Spinelli, Mitra M. Safavi, Najih Naser, Omar Khan
Advances in Microbiology (AiM) , 2013, DOI: 10.4236/aim.2013.37070
Abstract:

This study characterizes the 19 kDa protein expressed by Mycobacterium avium subspecies paratuberculosis (MAP) as a glycolipoprotein, providing the foundation for future experiments regarding its antigenicity and role in disease pathogenicity. We have previously shown that a 4.8 kb insert from MAP will produce a 16 kDa recombinant protein when expressed in Escherichia coli and 19 kDa recombinant protein when expressed in M. smegmatis (smeg19K). The difference of 3 kDa in size of these expressed proteins may be related to post translational modifications that occur in Mycobacterium species. We hypothesized that smeg19K is a glycolipoprotein since BLAST analysis revealed approximately 76% amino acid identity between the MAP 19 kDa protein and a known lipoglycoprotein, the 19 kDa protein of M. tuberculosis. This prediction was confirmed by the following positive staining of smeg19K with Sudan Black 4B, a postelectrophoresis dye used to stain for lipids. Smeg19K has also stained positively for glycosylation with the lectin concavalin A, a highly specific stain for mannose residues. As expected, treatment with tunicamycin (an antibiotic known to inhibit N-glycosylation) and treatment with deglycosylation assay (non-specific for mannose), showed no reduction in size of 19 kDa glycolipoprotein.

One Stage Anterior Reconstruction and Posterior Instrumentation in Surgical Management of Thoracolumbar Spine Fractures  [PDF]
Khaled Omran, Hesham Ali, Ahmed Saleh, Ahmed Omar, Ibrahim Elhawery, Ali Zein A. A. Alkhooly
Open Journal of Orthopedics (OJO) , 2015, DOI: 10.4236/ojo.2015.51002
Abstract: Background: The different methods of anterior reconstruction and posterior instrumentation in surgical management of thoracolumbar spine fractures are PLIF, TLIF, lateral extracaviatary and transpedicular techniques which are increasingly used to perform partial or total corpectomies and anterior reconstructions from a posterior approach. These techniques were being alternative to the standard anterior approach with less morbidity and mortality. Patients and Methods: This study was performed between 2011 and 2014 on 100 patients with acute unstable thoracolumbar spine fractures which were divided into four groups: 30 patients underwent (TLIF), 28 patients underwent (PLIF), 28 patients underwent (PA) and 14 patients underwent (TPA). Neurological outcome, complications, operative times, kyphotic angle, vertebral height loss, spinal canal compromise, pulmonary functions, Denis pain and work scale, VAS score, ODI score, hospital stay, and estimated blood loss (EBL) were evaluated and compared in between the four groups. Results: There was a higher complication rate, increased EBL, and longer operative time with posteroanterior (PA) compared with PLIF, TLIF and (TPA). Patients undergoing PLIF, TLIF and TPA had a greater recovery of neurological function than those in whom PA were performed. Conclusion: TPA appeared to have more favorable results in improving the clinical and radiological outcome and no complications were reported apart from superficial wound infection which healed rapidly. The PLIF, TLIF and TPA appeared to have a comparable morbidity rate to PA. The different methods of anterior reconstruction from posterior approach are more favorable, applicable and convenient than PA approach.
Implementing Surviving Sepsis Campaign Guidelines and Mortality of Adult Patients in Intensive Care Units: An Integrative Review  [PDF]
Saleh Al Omar, Inaam Khalaf, Jafar Alasad Alshraideh
Open Journal of Nursing (OJN) , 2019, DOI: 10.4236/ojn.2019.910078
Abstract: Background: Sepsis is a common dangerous body response to infection that can deteriorate into septic shock. Both sepsis and septic shock require early and timely managed care, which can be implemented by using the Surviving Sepsis Campaign (SSC) guidelines for management of sepsis and septic shock. The purpose of this study was to examine the literature related to the effect of implementing SSC guidelines for management of sepsis and septic shock on adult patients’ mortality rate in Intensive Care Units (ICUs). Methods: The method of Whittemore and Knafl was used to guide this integrative literature review. The literature search revealed 16 eligible quantitative research studies between 2004 and 2018. The quality of methods used in the included articles was assessed and data were analyzed. Results: Results showed that implementing SSC guidelines reduced the mortality rate among adult patients in ICUs. In addition, implementing selected practices from SSC guidelines, such as collecting blood cultures and administration of a broad-spectrum antibiotic and vasopressors were found to decrease the mortality rate among adult patients in ICUs. The SSC guidelines need to be taught to nurses and nursing students to increase their awareness and capability of implementing these guidelines in clinical practice.
Synthesis and Characterization of Sb65Se35-xGex Alloys  [PDF]
Saleh Ahmed Saleh
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.27127
Abstract: Density, chemical, structural and vibrational studies of Sb65Se35-xGex system with 0 ≤ x ≤ 20 produce by melt-quench technique were carried out using Archimedes method, Energy Dispersive Spectroscopy (EDS), X-ray diffraction (XRD) and Raman spectroscopy. All specimens are polycrystalline in nature as confirmed by XRD pattern. The compositional dependence of the XRD and Raman spectra suggests the presence of two basic structural units, SbSe3 pyramids with three-fold coordinated Sb atom at the apex and GeSe4 tetrahedrons. The compositional dependence of these physic Chemical properties of the investigated samples are investigated and discussed in light of many models. PACS: 68.55. Ln; 61.50. Ks; 68.55.Jk
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