30 research outputs found

    The Contrivance of New Mud Bricks for Restoring and Preserving the Edfa Ancient Granary - Sohag, Egypt

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    A mud brick functions as an element of masonry structures. Being an integral part of a wall mass, it must be understood structurally and chemically. The susceptibility of a mud brick to be affected by decay agents depends on the type of raw materials used, the methods of construction, location, the microclimatic conditions, the mechanical and microstructural characteristics of the mud brick itself. In this research, mineralogical composition and granulometric distribution of ancient mud bricks were studied by using some scientific techniques such as XRD, SEM and electrical mechanical sieves, to determine the main components and characteristics, which will serve as reference for the contrivance of new mud bricks. In addition, special knowledge of the physical properties of historic mud bricks were defined by some scientific techniques to get some information about their properties, such as density, porosity, water absorption and shrinkage. Furthermore, all of those characteristics were studied in two groups of new mud bricks, to determine their properties. Finally, ourresults proved that the 6th category in the 1st group and the 10th category in the 2nd group are the most appropriate types for restoring and preserving the studied monument, due to their good physical properties, morphological appearances and their suitable characteristics

    Proactive Location-Based Scheduling of Delay-Constrained Traffic Over Fading Channels

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    In this paper, proactive resource allocation based on user location for point-to-point communication over fading channels is introduced, whereby the source must transmit a packet when the user requests it within a deadline of a single time slot. We introduce a prediction model in which the source predicts the request arrival TpT_p slots ahead, where TpT_p denotes the prediction window (PW) size. The source allocates energy to transmit some bits proactively for each time slot of the PW with the objective of reducing the transmission energy over the non-predictive case. The requests are predicted based on the user location utilizing the prior statistics about the user requests at each location. We also assume that the prediction is not perfect. We propose proactive scheduling policies to minimize the expected energy consumption required to transmit the requested packets under two different assumptions on the channel state information at the source. In the first scenario, offline scheduling, we assume the channel states are known a-priori at the source at the beginning of the PW. In the second scenario, online scheduling, it is assumed that the source has causal knowledge of the channel state. Numerical results are presented showing the gains achieved by using proactive scheduling policies compared with classical (reactive) networks. Simulation results also show that increasing the PW size leads to a significant reduction in the consumed transmission energy even with imperfect prediction.Comment: Conference: VTC2016-Fall, At Montreal-Canad

    Physical Deterioration of Egyptian Limestone Affected by Saline Water

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    This study is the second in a series of experiments that describe the chemical, physical and thermal properties of archaeological limestone affected by salt and saline water in Egypt. This research aims to study the aggressive physical effects of different types of salts dominated in saline water and their different mechanisms on the acceleration of weathering processes that affect Egyptian limestone. It presents a multidisciplinary approach to characterize, at both micro/macro scales, the behavior of a limestone widely used as a construction material in most of Egyptian monuments when interacting with some types of salt solutions of various concentrations. A systematic optical, morphological, physical and mechanical analysis of the fresh and weathered stone samples were used to evaluate different characteristics through using scientific some techniques such as optical microscope (OP) and scanning electron microscope (SEM). In addition to the using of some special computer programs that were used to define different physical and mechanical properties such as weight changes, bulk density, total porosity, water uptake, water content, thermal dilatation and abrasion resistant. The results proved that all investigated samples were gradually affected by the types of salinity paths and salt concentrations. These results will serve as a database for the future comparison of long term behavior of stones before and after the planned conservation of the entire area. So, it is pertinent to device some scientific methods and interventions to reduce all factors of salt effects and removing their harmful aspects from historic fabric of the archaeological buildings through some scientific recommendation

    ENHANCEMENT OF DISSOLUTION RATE OF HYDROCHLOROTHIAZIDE

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    Objective: The aim of this study was to enhance the dissolution rate of hydrochlorothiazide (HCTZ).Methods: Binary solid dispersions (SDs) of HCTZ with increasing weight ratios of poloxamer 407, polyethylene glycol 6000 (PEG 6000) or gelucire 50/13 were prepared by solvent evaporation technique. The solid dispersions were deposited on the surface of aerosil 200 to produce a dry product with large surface area. The SDs were characterized with respect to drug dissolution. The mechanism of dissolution enhancement was researched using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC).Results: The unprocessed drug showed erratic, slow dissolution which can be explained on the basis of its hydrophobic nature. Preparation of SDs with hydrophilic carriers resulted in a significant increase in the dissolution rate with most of the drug being liberated in the first 5 min. The dissolution pattern of the drug from the prepared SDs depends mainly on the type of polymer used, and the best dissolution pattern was observed in the SD prepared using 1:1 ratio of the drug to gelucire 50/13 in the presence of aerosil 200 as a carrier. FTIR studies revealed no interaction between the drug and polymers. DSC showed a change in the crystalline structure of the drug after SDs formation. This change can explain the recorded dissolution enhancement.Conclusion: The study presented a system capable of increasing the dissolution rate of HCTZ using polymers which can increase the intestinal permeability as well.Keywords: Hydrochlorothiazide, Poloxamer 407, PEG 6000, Gelucire 50/13, Solid dispersion, Dissolutio

    A New Flavonoid C-Glycoside from Celtis australis L. and Celtis occidentalis L. Leaves and Potential Antioxidant and Cytotoxic Activities

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    A major development over the past two decades has been the realization that free radical induced lipid peroxidation and DNA damage are associated with major health problems, e.g. cancer and ageing. Plant-derived antioxidants are increasingly found beneficial in protecting against these diseases. Celtis australis L. and Celtis occidentalis L. are two plants that have a variety of uses in folk medicine but have not been evaluated before for their antioxidant and cytotoxic properties. Therefore, the extracts of both plants’ leaves were investigated for these activities, as well as isolation of the bioactive compounds responsible for the activities. Molecular structures of the compounds were elucidated by UV, HRESIMS, 1D (1H and 13C) and 2D (1H-13C HSQC and 1H-13C HMBC) NMR analyses. The ethanolic and aqueous extracts, n-butanol fractions and the isolated major compound were tested for their antioxidant activity using DPPH radical scavenging assay, xanthine oxidase-induced generation of superoxide radical and lipid peroxidation assay by thiobarbituric acid-reactive substances (TBARS) method using rat tissue homogenates. Cytotoxic activities were studied using standard MTT assay. A novel flavonoid C-triglycoside, 4‴-α-rhamnopyranosyl-2″-O-β-d-galactopyranosylvitexin, was isolated from both plants’ leaves, together with seven known flavonoids. The n-butanol fractions and the major compound 2″-O-β-galactopyranosylvitexin showed significant antioxidant activities, more pronounced than the tested standards BHT and dl-α-tocopherol in most tests. All extracts showed variable cytotoxic activities. This study provides strong evidence for the antioxidant and cytotoxic activities of the extracts of Celtis australis L. and Celtis occidentalis L. leaves, which were attributed to the polar n-butanol fractions and the major isolated flavonoid 2″-galactosylvitexin

    Detection and Molecular Characterization of Some Virulence Genes of Escherichia Coli Isolated from Milk in Dairy Cow Farms

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    Coliform pathogens, primarily E. coli, were discovered throughout the farm, causing environmental mastitis and can be shed from the udder into the milk; they are concerned about severe gastrointestinal disruption and potential enteropathogenic and/or toxic strains, posing a risk to public health. The objectives of this study were to identify the incidence and harmful serotypes of pathogenic Escherichiacoliand some of their virulent genes, which were isolated from the collected milk of some dairy farms in the Delta region and Cairo-Alexandria desert road farms, in Egypt during one year using the polymerase chain reaction (PCR) technique after bacteriological and serological identification as well as determine the antimicrobial susceptibility of the isolated strains. 150 milk samples in total were gathered (100 milk samples from bulk milk tanks and the other 50 samples from clinically mastitic dairy cows). According to our finding, the mean values of somatic cell count (SCC), standard plate count (SPC), and coliform count (CC) in the hundred bulk tank milk samples were 3.67  1.08×104/ml, 7.08×104± 6.25×104 cfu/ml and 3.04×102±1.43×102/ml, respectively. The bacteriological investigation exhibited that, the Escherichiacoli incidences from bulk tank milk (BTM) and mastitic milk samples (MMS) were 12% and 18%, respectively. The detected   E.coli serotypes including, O26, O44, O55:K99, O111, O119 and O157:H7 from MMS, while O1, O55, O78, O86, O124 and O158:H10 from BTM. Molecular virulence characterization of E.coli strains showed that, Shiga toxins 2 (stx2) gene is present in O157:H7, while the stx1 gene present in O26.  The Intimin gene (eaeA) is involved in four strains, O44, O111, O119, and O157:H7. Positive amplification of a biofilm gene (adrA) appeared in all E.coli strains. The outcome of the antimicrobial susceptibility revealed high resistance to amoxicillin (85.71%), streptomycin (80.95%), ampicillin (71.43%), and flucloxacillin (61.90%). Meanwhile, the highest susceptibility was to ciprofloxacin (95.24%) followed by enrofloxacin (90.48%), neomycin (80.95%), and gentamycin (76.19%). Effective hygienic measurements are required to avoid toxigenic and pathogenic E.coli and more future studies should be performed to increase awareness in dairy farms

    Immunostaining with D2–40 improves evaluation of lymphovascular invasion, but may not predict sentinel lymph node status in early breast cancer

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    <p>Abstract</p> <p>Background</p> <p>Sentinel lymph node (SLN) biopsy is a widely used diagnostic procedure in the management of early breast cancer. When SLN is free of metastasis, complete axillary dissection may be skipped for staging in clinically N0 patients, allowing a more conservative procedure. Histological tumor features that could reliably predict SLN status have not yet been established. Since the degree of tumor lymphangiogenesis and vascularization may theoretically be related to the risk of lymph node metastasis, we sought to evaluate the relationship between lymph vessel invasion (LVI), lymphatic microvascular density (LVD), microvascular density (MVD) and VEGF-A expression, with SLN status and other known adverse clinical risk factors.</p> <p>Methods</p> <p>Protein expression of D2–40, CD34, and VEGF-A was assessed by immunohistochemistry on paraffin-embedded sections of primary breast cancer specimens from 92 patients submitted to SLN investigation. The presence of LVI, the highest number of micro vessels stained for D2–40 and CD34, and the protein expression of VEGF-A were compared to SLN status, clinicopathological features and risk groups.</p> <p>Results</p> <p>LVI was detected in higher ratios by immunostaining with D2–40 (p < 0.0001), what would have changed the risk category from low to intermediate in four cases (4.3%). There was no association between LVI and other angiogenic parameters determined by immunohistochemistry with SLN macrometastases, clinical features or risk categories.</p> <p>Conclusion</p> <p>Assessment of LVI in breast carcinoma may be significantly increased by immunostaining with D2–40, but the clinical relevance of altering the risk category using this parameter may not be advocated according to our results, neither can the use of LVI and LVD as predictors of SLN macrometastasis in early breast cancer.</p

    Overview of biologically digested leachate treatment using adsorption

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    Biological process is effective in treating most biodegradable organic matter present in leachate; however, a significant amount of ammonia, metals and refractory organic compounds may still remain in this biologically digested leachate. This effluent cannot be released to receiving bodies until the discharge limit is met. Several physical/chemical processes have been practiced as post-treatment to remove the remaining pollutants including coagulation–flocculation, oxidation and adsorption. Adsorption is often applied in leachate treatment as it enhances removal of refractory organic compounds. This chapter will focus on works related to adsorption as one of the commonly used methods to treat biologically digested leachate further down to acceptable discharge limit

    Overview of biologically digested leachate treatment using adsorption

    Get PDF
    Biological process is effective in treating most biodegradable organic matter present in leachate; however, a significant amount of ammonia, metals and refractory organic compounds may still remain in this biologically digested leachate. This effluent cannot be released to receiving bodies until the discharge limit is met. Several physical/chemical processes have been practiced as post-treatment to remove the remaining pollutants including coagulation–flocculation, oxidation and adsorption. Adsorption is often applied in leachate treatment as it enhances removal of refractory organic compounds. This chapter will focus on works related to adsorption as one of the commonly used methods to treat biologically digested leachate further down to acceptable discharge limit

    MOSQUE DESIGN IN LIGHT OF PSYCHO-RELIGIOUS EXPERIENCE (ISLAMIC)

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    Studies on mosque architecture have tended to be merely descriptive, and while a few have gone beyond description, a theoretical base to guide architects has been lacking. This study is an attempt to formulate a set of guiding principles derived from literary sources and traditional mosques, and is conceived on the basis of the psycho-religious experience that one encounters while engaged in prayer. The psychological theories of suggestion, psychoanalysis, and psychosynthesis are found to be applicable to mosque architecture. The architectural and formal elements of mosques are ordered according to these psychological principles, identified in this study as design parameters. These design parameters facilitate the performance of prayer and, indeed, transform prayer from its secondary, ritualistic type into its primary, genuine one. These psychological processes that the mosque serves have kept the essence of prayer alive, and, on the other hand, they have an impact on those who experience the building, e.g., the users or those who are engaged in the building of this structure, such as the architects or the patrons. This impact, from a purely psychological perspective, is therapeutic in nature. The mosque, with its architectural and decorative elements, evokes therapeutic responses. The mosque thus has, in addition to its religious and educational role, the function of being a room in the city in which the psychological well-being of individuals is served. To accomplish the concretization of this physical environment, Islamic law has provided legal parameters, which correspond closely with the three therapeutic psychological parameters mentioned above. Seen in this context, the mosque is a man-made environment, and contains innovations (bida(\u27c)), yet it is the physical expression of a society that applies its best religious and logical powers in the effort to maintain an acceptable level of human well-being
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