28 research outputs found

    Electromagnetic Modeling for Radar Remote Sensing of Snow-Covered Terrain

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    This thesis investigates the radar remote sensing of snow-covered terrain for estimation of snow equivalent water on global scale. The importance and impact of this research stems from the fact that water from snowmelt is the major source of water for inland cities and agriculture during summer. This effort is focused on developing a physics-based model for snow and a fully coherent polarimetric scattering model for snow above ground. Both the physical model and the forward polarimetric scattering model present a significant improvement compared to the existing models for snowpack. Computer-generated snow media are constructed using 3-D spatial exponential correlation functions, along with Lineal-Path functions that serve to preserve the connectivity of the snow particles. A fully-coherent model is presented through the use of the Statistical S-matrix Wave Propagation in Spectral-Domain (SSWaP-SD) technique. The SSWaP-SD depends on the discretization of the medium into thin slabs. Several realizations of a thin snow slab are solved numerically to form the statistics of the scattering matrix representing such a thin snow layer. For each thin slab of the snow-pack, a corresponding polarimetric N-port (representing different directions of scattering) S-matrix is generated. These S-matrices are cascaded using the SSWaP-SD method to calculate the total forward and backward bistatic scattered fields in a fully coherent way. The SSWaP-SD, in conjunction with a Method of Moments (MoM) code based on the Discrete-Dipole Approximation (DDA), is chosen to leverage both the time-efficient computations of the DDA and the full-coherency of the SSWaP-SD method, simultaneously. In addition to the MoM-DDA, a Finite Element Method (FEM) based on commercial software is used for cross-comparison and validation. The simulation results of the backscattering from an arbitrary thick snow layer are presented and validated with measurements. The underlying rough ground surface response is then estimated through both an analytical technique based on the Physical Optics (PO) method and a numerical solver based on MoM using a commercial full-wave solver. Finally, the complete response is then calculated by cascading the S-matrices representing the snow and the rough surface responses. The simulation results of the backscattering are presented using a Monte-Carlo process, which show very good agreement with measurements.PHDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/167972/1/mzaky_1.pd

    Synthesis, characterization and catalytic activity of Cu(II), Co(II), Ni(II), Mn(II) and Fe(III) complexes of 4-((3-formyl-4-hydroxyphenyl)diazenyl)-N-(4-methyloxazol-2-yl) benzenesulfonamide

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    The sulfonamide derivative, 4-((3-formyl-4-hydroxyphenyl)diazenyl)-N-(4-methyloxazol-2-yl) benzenesulfonamide (FDMB), was synthesized and characterized. Additionally, its Cu(II), Co(II), Ni(II), Mn(II) and Fe(III) complexes were prepared and their structures were investigated by elemental analysis, thermal analysis and (IR, electronic and EPR) spectroscopy. The mode of binding indicates that the ligand binds to the metal ion through carbonyl oxygen and OH phenolic with displacement of its proton. The Co(II) complex was applied for the hydrolysis of nerve agent-like compound, bis-(p-nitrophenyl) phosphate (BNPP). The results showed a significant rate enhancement of 2.5 million fold with respect to the auto-hydrolysis of BNPP under the same conditions

    Impact of Sunflower Meal Protein Isolate Supplementation on Pasta Quality

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    Globally, there is an increased demand for plant- and animal-derived proteins. However, animal-derived proteins are still expensive and expected to negatively impact the environment. Sunflower seeds, an excellent source of proteins, are one of the most critical oilseeds produced in the world markets. This study used sunflower meal protein isolate (SMPI), wheat flour (WF), and their blends to make pasta with good sensory features and higher nutritional value. The chemical and amino acid compositions, rheological properties, color attributes, cooking quality, sensory properties, and texture analysis of pasta were evaluated. SMPI showed a high protein content (87.12%) compared to WF (10.90%). The pasta was made from WF with supplementing SMPI at three concentrations (3.0, 6.0, and 9.0% w/w) to improve the nutritional quality. Farinograph parameters showed that water absorption, arrival time, dough development time, mixing tolerance index, dough weakening, and dough stability increased as the percentage of SMPI in the blends increased. The results also showed that the color (L*, a*, and b*) of pasta samples was darker as the mixing level of SMPI increased. The obtained sensorial results confirmed this result. The cooking quality of pasta revealed that the weight, volume, and cooking loss of prepared pasta with SMPI (3.0–9.0%) increased compared to the control sample (pasta with 100% WF). Moreover, sensory evaluation of pasta revealed that all samples were acceptable. Nonetheless, mouth feel and overall acceptability of pasta reinforced with 3.0 and 6.0% SMPI did not notably impact the pasta compared to the control sample, while flavor did not significantly influence the pasta with 3.0% SMPI. These findings demonstrated that pasta supplemented with SMPI could benefit the pasta industry, which requires a suitable technological process to obtain novel products

    Tailoring Apixaban in Nanostructured Lipid Carrier Enhancing Its Oral Bioavailability and Anticoagulant Activity

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    Apixaban (Apx), an oral anticoagulant drug, is a direct factor Xa inhibitor for the prophylaxis against venous thromboembolism. Apx has limited oral bioavailability and poor water solubility. The goal of this study was to improve the formulation of an Apx-loaded nanostructured lipid carrier (NLC) to increase its bioavailability and effectiveness. As solid lipid, liquid lipid, hydrophilic, and lipophilic stabilizers, stearic acid, oleic acid, Tween 80, and lecithin were used, respectively. Utilizing Box–Behnken design, the effects of three factors on NLC particle size (Y1), zeta potential (Y2), and entrapment efficiency percent (Y3) were examined and optimized. The optimized formula was prepared, characterized, morphologically studied, and pharmacokinetically and pharmacodynamically assessed. The observed responses of the optimized Apx formula were 315.2 nm, −43.4 mV, and 89.84% for Y1, Y2, and Y3, respectively. Electron microscopy revealed the homogenous spherical shape of the NLC particles. The in vivo pharmacokinetic study conducted in male Wistar rats displayed an increase in AUC and Cmax by 8 and 2.67 folds, respectively, compared to oral Apx suspension. Moreover, the half-life was increased by 1.94 folds, and clearance was diminished by about 8 folds, which makes the NLC formula a promising sustained release system. Interestingly, the pharmacodynamic results displayed the superior effect of the optimized formula over the drug suspension with prolongation in the cuticle bleeding time. Moreover, both prothrombin time and activated partial thromboplastin time are significantly increased. So, incorporating Apx in an NLC formula significantly enhanced its oral bioavailability and pharmacodynamic activity

    Cutaneous Metastases from DifferentInternal Malignancies in Egypt

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    Background:Cutaneous metastasis is defined as the spread of malignant cells froma primary malignancy to the skin. Generally, cutaneous involvement from internal malignancies is uncommon. No reports have focused on the cutaneous metastasis profiles in Egypt or the Middle Eastern population. In this study, we seek to determine the rates at which different internal malignancies give rise to cutaneous metastases upon first diagnosis of the primary tumor.Methods:Patients with internal malignancies who attended the South Egypt Cancer Institute from January 2004 through May 2010 were examined and followed to identify cutaneous metastases, which were confirmed by biopsy and histological evaluation.Results:Among 2208 cases of internal malignancies, 48 cases of cutaneous metastases were detected. The clinical profiles were similar to those from western and Asian countries, although the frequencies of primary tumors differed. Most commonly in Egypt breast cancer and urinary bladder cancers were seen.Conclusion:The risk of skin metastases depends largely on the characteristics of tumor cells, which are similar among different groups

    Improvement effects of green tea and pumpkin oils on myelin oligodendrocyte glycoprotein-induced Multiple sclerosis in rats

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    Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system (CNS) associated with significant progressive neurodegeneration. There is a lot of interest in the use of plant-based essential oils in traditional medicine to treat and prevent human illnesses, including MS. This research aimed to assess the neuroprotective effects of green tea oil (GTO) and pumpkin oil (PO) against myelin oligodendrocyte glycoprotein (MOG)-induced MS in Wistar rats as well as investigate the underlying molecular mechanisms. The Wistar rats were divided into four groups: group 1, normal control; group 2, MOG-injected; and groups 3 and 4, MOG-injected groups treated with 5 ml/kg body weight each of GTO and PO, respectively. The chemical profiles of components within a GTO and PO were identified using gas chromatography-mass spectrometry (GC–MS). Treatment with GTO and PO substantially improved the decreased dopamine, serotonin, norepinephrine, and acetylcholine levels in the brain of the MOG-injected rats. It also suppressed the elevated epinephrine levels. The histological injuries in the brain cortical tissue of the MOG-injected group were notably improved after supplementing with GTO and PO. Furthermore, brain lipid peroxidation and serum INF-β concentration were significantly lower in the MOG-injected rats treated with GTO and PO. The brain GSH, SOD, GPx, as well as serum coenzyme Q10, and α-tocopherol levels were significantly enhanced by GTO and PO supplementaion. Additionally, GTO and PO administration into MOG-injected rats significantly upregulated Nrf2, Bcl-2, and PCNA while significantly downregulated TNF-α, NF-κB, iNOS, p53, and Bax expression levels. Taken together, these findings suggest that GTO and PO efficiently ameliorate MOG-induced MS via enhancing the antioxidant, anti-inflammatory, and anti-apoptotic effects

    Different Techniques for the Management of Meniscal Ramp Lesions Using Standard Anterior Portals

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    There is strong association between meniscal lesions and anterior cruciate ligament injuries. Recently, light was shown on a new entity: ramp lesions. The incidence of these lesions and their management is still unclear. Although some believe that some lesions, when stable, can be managed conservatively, most surgeons repair ramp tears. Accessibility of these tears is challenging; they are best accessed through posterior portals, which is time-consuming and poses potential risk to vital structures. Our technique allows access to and management of ramp lesions through safe standard anterior portals. Ramp lesions are searched for as a routine step during anterior cruciate ligament reconstruction by advancing the scope through the intercondylar notch just beside the medial femoral condyle. If a lesion is found, it is repaired; only very stable small tears are treated with needling to refresh the edges and induce a healing response. A simple suture, horizontal mattress suture, or a circumferential stitch is used

    Simple Cost-Effective Reinsertion of Avulsed Medial Patellofemoral Ligament in Acute Patellar Dislocation

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    The medial patellofemoral ligament (MPFL) is the main restraining force against lateral patellar displacement in the first 20° of flexion and is disrupted after patellar subluxation or dislocation. Management of acute patellar dislocations is controversial, and many clinicians opt for conservative treatment in the acute phase. However, a traumatic rupture of the MPFL warrants surgical attention. Several considerations must be made by surgeons attempting reinsertion of the MPFL, including the choice of implant and timing of surgery, to restore the anatomy and biomechanics of the patellofemoral joint. Our aim is to achieve robust reinsertion of the MPFL restoring the anatomy and biomechanics of the patellofemoral joint using a simple, reproducible, and economical technique. We present MPFL reinsertion to the medial border of the patella in an acute patellar dislocation with a braided No. 2 ultrahigh-molecular-weight polyethylene suture (No. 2 Ultrabraid; Smith & Nephew, Memphis, TN) that is passed through 3 transverse parallel tunnels and tied over a bone bridge on the lateral border of the patella. This technique is simple with no implanted hardware, does not have the risk of donor-site morbidity of MPFL reconstruction, and can be performed in skeletally immature patients without growth plate concerns
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