425 research outputs found

    Developed Computational Methodology for the Most Effective Design of Open Channel Cross Sections

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    Open channel is the most important way to convey water for various purposes. Channels cost a lot of money to construct. The optimal design means delivering water with efficiency, safely, and economical costs of construction. The determinant of minimum cost must take into account the effect of manning coefficient variation between the sides and the bed. The proposed program is solved using the Shuffled complex evolution method developed at the University of Arizona (SCE-UA) algorithm. The results obtained in this study are compared with existing models developed by others in the past using either the complex equations or the Simultaneous Perturbation Stochastic Approximation (SPSA) technique. The result shows that the existing optimization problem formulations, when solved using SCE-UA, provided results compared to those solved using the Lagrange multiplier method. The results obtained in this study indicate that approximately 34% of cost savings can be achieved. Also, the provided results were compared to those obtained by others in the past using (SPSA) technique. The results obtained in this study indicate that approximately 36.5% of cost savings can be achieved. It was found that the (SCE-UA) technique is more accurate than (SPSA) and has the lowest total construction cost

    Wave attenuation in partially filled unsteady pipe flow

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    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Much research activity is carried out to reduce water consumption for domestic purposes. This leads to the possibility of reducing the amount of water introduced into building drainage systems. However, an accurate estimation of the flow attenuation within building drainage pipes is of great importance to prevent solid eposition and subsequent blockage. The research is focused on the field of subcritical flow in partially-filled pipes. Experimental and numerical investigations have been carried out to study the wave attenuation in the following configurations encountered in drainage pipe systems: i) A simple pipe, ii) A pipe subject to one concentrated lateral inflow, iii) A pipe with gate fixed at the downstream section, generating an interaction between wave and backwater profiles. In the present study the Saint-Venant equations are derived in their general and characteristic forms. A number of numerical procedures for solution of the Saint-Venant equations are reviewed, and the rectangular grid characteristics method, diffusing scheme and Strelkoff's implicit method are chosen to solve the equations. The stability of the finite-difference methods used is investigated for free-outfall and controlled outfall boundary conditions. An experimental installation consisting of 0.105 m diameter uPVC pipe is used to investigate the characteristics of the flow and to form test cases for the numerical methods. Comparisons between computed and observed depth hydrographs, peak depths and depth variations along the pipe are made for subcritical flow in a pipe of slope 1/300. The rectangular-grid characteristics method and the diffusing scheme are also applied to supercritical flow. Flow tests are undertaken for supercritical flow in a pipe of slope 1/200 to validate the use of these methods. The investigation revealed that the attenuation rate of peak depths is affected by the volume of the waves. The implicit method is the most suitable method, dealing efficiently with most problems encountered in drainage pipe systems of flat slope. The diffusing scheme can model the attenuation of supercritical flow within building drainage pipes.Financial support from the ORS Award Scheme, Mechanical Engineering Department of Brunel University and Egyptian Government are acknowledged

    Production of phenolic compounds from Spirulina maxima microalgae and its protective effects

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    The purpose of this study was to illustrate the enhancing process of phenolics synthesis in Spirulina maxima grown in Zarrouk’s medium supplemented with different concentration of NaNO3 and/or combined with phenylalanine (L-PA). Also, the protective efficacy of Spirulina polyphenolic (SPP) extracts against CCI4-induced microsomal lipid peroxidation and scavenging of hydroxyl radical formation were performed. The results revealed that the levels of NaNO3 and L-PA in growth medium had positive effects on the production of biomass (34-64 mg/day), total phenolics (4.51-16.96 mg/g d.w) and flavonoids (1.32-5.12 mg/g d.w) contents. The highest levels of these compounds were obtained in Zarrouk’s medium containing 3.77 g/L NaNO3 and 100 mg/L L-PA. The HPLC-DAD profile of all phenolic extracts of Spirulina showed the presence of large numbers of phenolic acids and flavonoids, in variable levels. Gallic, chlorogenic, cinnamic, pinostrobin and p-OH-benzoic were found as the mostabundant constituents among different extracts. Polyphenolic of Spirulina exhibited antioxidant effects  CCI4-induced lipid peroxidation (inhibition %) in liver homogenate and on DPPH radical scavenging activity (with IC50 values ranged from 23.22 to 35.62 ìg/ml), in dose-depended manner. Their protective potential was comparable to that of standard phenolic antioxidants (BHT, BHA and -tocopherol, with IC50 values ranged from 13.22 to 23.62 ìg/ml). Thus, S. maxima can be regarded as potent naturalsources of nutraceutical and functional ingredients

    Pilot Scale of Microalgal Production Using Photobioreactor

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    Microalgal gained much interest as a promising sustainable feedstock for the production of food, feed, bulk chemicals and biofuels. Pilot scale of microalgal is needed to bridge the gap between laboratory scale research and commercial application. Commercial applications of microalgal have been used for a wide array of functions including, pharmaceutical, health sector, nutraceutical, cosmetics and agriculture. Numerous photobioreactors (PBRs) of different volume and shapes have been designed. Cost of PBR has a major influence on production cost for large scale biomass. There are several ways to reduce production cost depends on the type of algal strain, type of PBRs, CO2 and the production technology of the biomass. Dilution rate is an important factor, which affects the biomass productivity, rate and ultimately what needs to be maximized

    Magnetic resonance spectroscopy of the frontal region in patients with metabolic syndrome : correlation with anthropometric measurement

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    Purpose: to demonstrate 1H-MR spectroscopy of the frontal region in patients with metabolic syndrome and to correlate the metabolic ratios with anthropometric measurement. Material and methods: A prospective study was conducted upon 20 patients with metabolic syndrome (10 male, 10 female; mean age 52 years) and 20 age- and sex-matched volunteers. Patients were mild-moderate (n = 14) and marked and morbid obesity (n = 6). Patients and volunteers underwent 1H-MR spectroscopy of the frontal region. The Ch/Cr and NAA/Cr ratio were calculated and correlated with anthropometric measurement. Results: The Cho/Cr and NAA/Cr of patients with Mets (1.03 ± 0.08 and 1.62 ± 0.08) were significantly different (p = 0.001) to those of volunteers (0.78 ± 0 and 1.71 ± 0.61, respectively). The Cho/Cr and NAA/Cr cutoffs used to differentiate patients from volunteers were 0.89 and 1.77 with areas under the curve of 0.992 and 0.867 and accuracy of 97% and 93%, respectively. There was a significant difference in Cho/Cr and NAA/Cr between patients with marked-morbid obesity and moderate-mild obesity (p = 0.001 respectively). Conclusions: We concluded that NAA/Cr and Cho/Cr ratios of the frontal region can differentiate patients with metabolic syndrome from volunteers and are well correlated with the anthropometric measurement

    Diagnostic and prognostic values of antikeratin antibodies (AKA) and collagen III propeptides (PIIINP) in juvenile rheumatoid arthritis

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    Background: The need for specific and sensitive diagnostic as well as prognostic markers for juvenile rheumatoid arthritis (JRA) has urged  scientific research toward this field.Objective: We sought to assess the diagnostic and prognostic values of serum and synovial fluid collagen III propeptides (PIIINP) and antikeratin antibodies(AKA) in JRA.Methods :Thirty-one JRA patients with a mean age of 10.6±4.2 years were enrolled in the study. They were compared to 10 SLE patients with arthritis and 15 age and sex matched healthy children as control groups. All  patients were subjected at enrollment to laboratory evaluation by CBC,  ESR, CRP, serum PIIINP and AKA. Patients with knee effusion were  subjected to AKA and PIIINP analysis in their synovial fluid samples. Clinical evaluation was done by examination of joint swelling, tenderness and limitation of movement scores. Also, radiological evaluation by plain X-ray films for hands, knees and feet using modified Larsen score (MLS) was performed. Laboratory, clinical and radiological evaluation methods were re-performed after 3 months of proper treatment. A third radiological evaluation was done one year after the first evaluation.Results: Serum PIIINP was significantly elevated in JRA patients  (12.8±8.7) ìg/L in comparison to healthy controls (7.0±1.9 ìg/L, p<0.05). However, no significant difference was observed when compared to SLE patients. Reduction of serum PIIINP was observed after 3 months of treatment with no significant difference between JRA patients (10.5±8.8 ìg/L) and the healthy controls. Synovial fluid PIIINP (56.4±6.6 ìg/L) was significantly higher than that of the serum (p<0.05). Neither serum nor synovial fluid PIIINP correlated with any of the laboratory, clinical or radiological parameters. The serum AKA positivity rate was significantly higher in JRA patients (77% at the study onset and 90% after three months) as compared to the control group (7%, p<0.001). Serum AKA values recorded a sensitivity, specificity and diagnostic efficiency in JRA patients of 77%, 93% and 83% at the study onset. These values increased after 3 months to 90%, 93% and 91% respectively. Synovial AKA levels displayed no significant difference in comparison to that of the serum.Conclusion :AKA is a specific and sensitive diagnostic marker for JRA. Meanwhile, PIIINP was significantly elevated during JRA disease activity particularly in the synovial fluid. Neither AKA nor PIIINP proved to have prognostic values in JRA.Key words: juvenile rheumatoid, arthritis, antikeratin antibodies, collagen III propeptides, SLE

    Milk clotting using peptidases of basidiomycetes

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    [no abstract

    Optimization of Growth Conditions for Purification and Production of L-Asparaginase by Spirulina maxima

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    L-asparaginase (L-AsnA) is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM) were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form) concentrations (1.25, 2.50, and 5.0 g/L) for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2) showed a high AsnA enzyme activity (898 IU), total protein (405 mg/g), specific enzyme activity (2.21 IU/mg protein), and enzyme yield (51.28 IU/L) compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima
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