Search results for: gel fraction
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 971

Search results for: gel fraction

971 Characterization of Domestic Sewage Mixed with Baker's Yeast Factory Effluent of Beja Wastewater Treatment Plant by Respirometry

Authors: Fezzani Boubaker

Abstract:

In this work, a comprehensive study of respirometric method was performed to assess the biodegradable COD fractions of domestic sewage mixed with baker’s yeast factory effluent treated by wastewater treatment plant (WWTP) of Beja. Three respirometric runs were performed in a closed tank reactor to characterize this mixed raw effluent. Respirometric result indicated that the readily biodegradable fraction (SS) was in range of 6-22%, the slowly biodegradable fraction (Xs) was in range of 33-42%, heterotrophic biomass (XH) was in range of 9-40% and the inert fractions: XI and SI were in range of 2-40% and 6-12% respectively which were high due to the presence of baker’s yeast factory effluent compared to domestic effluent alone. The fractions of the total nitrogen showed that SNO fraction is between 6 and 9% of TKN, the fraction of nitrogen ammonia SNH was ranging from 5 to 68%. The organic fraction divided into two compartments SND (11-85%) and XND (5-20%) the inert particulate nitrogen fraction XNI was between 0.4 and 1% and the inert soluble fraction of nitrogen SNI was ranged from 0.4 to 3%.

Keywords: wastewater characterization, COD fractions, respirometry, domestic sewage

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970 Bioassay Guided Isolation of Cytotoxic and Antimicrobial Components from Ethyl Acetate Extracts of Cassia sieberiana D.C. (Fabaceae)

Authors: Sani Abubakar, Oumar Al-Mubarak Adoum

Abstract:

The leaves extracts of Cassia sieberiana D. C. were screened for antimicrobial bioassay against Staphylococcus aureus, Salmonella typhi, and Escherichia coli and cytotoxicity using Brine Shrimp Test (BST). The crude ethanol extract, Chloroform soluble fraction, aqueous soluble fraction, ethyl acetate soluble fraction, methanol soluble fraction, and n-hexane soluble fraction were tested against antimicrobial and cytotoxicity. The Ethyl acetate fraction obtained proved to be most active in inducing complete lethality at minimum doses in BST and also active on Salmonella typhi. The bioactivity result was used to guide the column chromatography, which led to the isolation of pure compound CSB-8, which was found active in the BST with an LC₅₀ value of 34(722-182)µg/ml and showed remarkable activity on Salmonella typhi (zone of inhibition 25mm) at 10,000µg/ml. The ¹H-NMR, ¹³C NMR, FTIR, and GC-MS spectra of the compound suggested the proposed structure to be 2-pentadecanone.

Keywords: antimicrobial bioassay, cytotoxicity, column chromatagraphy, Cassia sieberiana D.C.

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969 A Simplified Model of the Control System with PFM

Authors: Bekmurza H. Aitchanov, Sholpan K. Aitchanova, Olimzhon A. Baimuratov, Aitkul N. Aldibekova

Abstract:

This work considers the automated control system (ACS) of milk quality during its magnetic field processing. For achieving high level of quality control methods were applied transformation of complex nonlinear systems in a linearized system with a less complex structure. Presented ACS is adjustable by seven parameters: mass fraction of fat, mass fraction of dry skim milk residues (DSMR), density, mass fraction of added water, temperature, mass fraction of protein, acidity.

Keywords: fluids magnetization, nuclear magnetic resonance, automated control system, dynamic pulse-frequency modulator, PFM, nonlinear systems, structural model

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968 Combustion Characteristic of Propane/Acetylene Fuel Blends Pool Fire

Authors: Yubo Bi, Xiao Chen, Shouxiang Lu

Abstract:

A kind of gas-fueled burner, named Burning Rate Emulator, was proposed for the purpose of the emulation of condensed fuel recently. The gaseous fuel can be pure combustible fuel gas or blends of gaseous fuel or inert gas. However, this concept was recently proposed without detailed study on the combustion characteristic of fuel blends. In this study, two kinds of common gaseous fuels were selected, propane and acetylene, to provide the combustion heat as well as a large amount of smoke, which widely exists in liquid and solid fuel burning process. A set of experiments were carried out using a gas-fueled burner with a diameter of 8 cm. The total volume flow rate of propane and acetylene was kept at 3 liters per minute. The volume fraction of propane varied from 0% to 100% at interval of 10%. It is found that the flame height increases with propane volume fraction, which may be caused by the increase of heat release rate, as the energy density of propane is larger than that of acetylene. The dimensionless flame height is correlated against dimensionless heat release rate, which shows a power function relationship. The radiation fraction of the flame does not show a monotonic relationship with propane volume fraction. With the increase of propane volume fraction from 0% to 100%, the value of radiation fraction increases first and reach a maximum value around 0.46 at a propane volume fraction of 10%, and then decreases continuously to a value of 0.25 at the propane volume fraction of 100%. The flame radiation is related to the soot in the flame. The trend of the radiation fraction reflects that there may be a synergistic effect of soot formation between propane and acetylene which can be guessed from the significantly high radiation fraction at a propane volume fraction of 10%. This work provides data for combustion of gaseous fuel blends pool fire and also give reference on the design of Burning Rate Emulator.

Keywords: Burning Rate Emulator, fuel blends pool fire, flame height, radiation fraction

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967 Gas-Liquid Two Phase Flow Phenomenon in Near Horizontal Upward and Downward Inclined Pipe Orientations

Authors: Afshin J. Ghajar, Swanand M. Bhagwat

Abstract:

The main purpose of this work is to experimentally investigate the effect of pipe orientation on two phase flow phenomenon. Flow pattern, void fraction and two phase pressure drop is measured in a polycarbonate pipe with an inside diameter of 12.7mm for inclination angles ranging from -20° to +20° using air-water fluid combination. The experimental data covers all flow patterns and the entire range of void fraction typically observed in two phase flow. The effect of pipe orientation on void fraction and two phase pressure drop is justified with reference to the change in flow structure and two phase flow behavior. In addition to this, the top performing void fraction and two phase pressure drop correlations available in the literature are presented and their performance is assessed against the experimental data in the present study and that available in the literature.

Keywords: flow patterns, inclined two phase flow, pressure drop, void fraction

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966 Hepatoprotective Evaluation of Potent Antioxidant Fraction from Urtica dioica L.: In vitro and In vivo Studies

Authors: Bhuwan C. Joshi, Atish Prakash, Ajudhia N. Kalia

Abstract:

Ethnopharmacological relevance: The plant Urtica dioica L. (Urticaceae) is used in various diseases including hepatic ailments. Traditionally, the leaves and roots of the plant are used in jaundice. Objective: The aim of the present work was to evaluate hepatoprotective potential of potent antioxidant from Urtica dioica L. against CCl4 induced hepatotoxicity in-vitro and in-vivo model. Materials and methods: Antioxidant activity of hydro alcoholic extract and its fractions petroleum ether fraction (PEF), ethyl acetate fraction (EAF), n-butanol fraction (NBF) and aqueous fraction (AF) were determined by DPPH radicals scavenging assay. Fractions were subjected to in-vitro cell line study. Further, the most potent fraction (EAF) was subjected to in-vivo study. The in-vivo hepatoprotective active fraction was chromatographed on silica column to isolate the bioactive constituent(s). Structure elucidation was done by using various spectrophotometric techniques like UV, IR, 1H NMR, 13C NMR and MS spectroscopy. Results and conclusion: The ethyl acetate fraction (EAF) of Urtica. dioica L. possessed the potent antioxidant activity viz. DPPH (IC50 78.99 ± 0.17 µg/ml). The in-vitro cell line study showed EAF prevented the cell damage. The EAF significantly attenuated the increased liver enzymes activities in serum and tissue. Column chromatography of most potent antioxidant fraction (EAF) leads to the isolation of 4-hydroxy-3-methoxy cinnamic acid which is responsible for its hepatoprotective potential. Hence, the present study suggests that EAF has significant antioxidant and hepatoprotective potential on CCl4 induced hepatotoxicity in-vitro and in-vivo.

Keywords: Urtica dioica L., antioxidant, HepG2 cell line, hepatoprotective

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965 Transient Analysis of Central Region Void Fraction in a 3x3 Rod Bundle under Bubbly and Cap/Slug Flows

Authors: Ya-Chi Yu, Pei-Syuan Ruan, Shao-Wen Chen, Yu-Hsien Chang, Jin-Der Lee, Jong-Rong Wang, Chunkuan Shih

Abstract:

This study analyzed the transient signals of central region void fraction of air-water two-phase flow in a 3x3 rod bundle. Experimental tests were carried out utilizing a vertical rod bundle test section along with a set of air-water supply/flow control system, and the transient signals of the central region void fraction were collected through the electrical conductivity sensors as well as visualized via high speed photography. By converting the electric signals, transient void fraction can be obtained through the voltage ratios. With a fixed superficial water velocity (Jf=0.094 m/s), two different superficial air velocities (Jg=0.094 m/s and 0.236 m/s) were tested and presented, which were corresponding to the flow conditions of bubbly flows and cap/slug flows, respectively. The time averaged central region void fraction was obtained as 0.109-0.122 with 0.028 standard deviation for the selected bubbly flow and 0.188-0.221with 0.101 standard deviation for the selected cap/slug flow, respectively. Through Fast Fourier Transform (FFT) analysis, no clear frequency peak was found in bubbly flow, while two dominant frequencies were identified around 1.6 Hz and 2.5 Hz in the present cap/slug flow.

Keywords: central region, rod bundles, transient void fraction, two-phase flow

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964 Interaction Effects of Dietary Ginger, Zingiber Officinale, on Plasma Protein Fractions in Rainbow Trout, Oncorhynchus Mykiss

Authors: Ali Taheri Mirghaed, Sara Ahani, Ashkan Zargar, Seyyed Morteza Hoseini

Abstract:

Diseases are the major challenges in intensive aquaculture that cause significant annual losses. Antibiotic-therapy is a common way to control bacterial disease in fish, and oxytetracycline (OTC) is the only oral antibiotic in aquaculture approved FDA. OTC has been found to have negative effects on fish, such as oxidative stress and immune-suppression, thus, it is necessary to mitigate such effects. Medicinal herbs have various benefits on fish, including antioxidant, immunostimulant, and anti-microbial effects. Therefore, we hypothesized if dietary ginger meal (GM) interacts with dietary OTC by monitoring plasma protein fractions in rainbow trout. The study was conducted as a 2 × 2 factorial design, including diets containing 0 and 1% GM and 0 and 1.66 % OTC (corresponding to 100 mg/kg fish biomass per day). After ten days treating the fish (60 g individual weight) with these feeds, blood samples were taken from al treatments (n =3). Plasma was separated by centrifugation, and protein fractions were determined by electrophoresis. The results showed that OTC and GM had interaction effects on total protein (P<0.001), albumin (P<0.001), alpha-1 fraction (P=0.010), alpha-2 fraction (P=0.001), beta-2 fraction (P=0.014), and gamma fraction (P<0.001). Beta-1 fraction was significantly (P=0.030) affected by dietary GM. GM decreased plasma total protein, albumin, and beta-2 but increased beta-1 fraction. OTC significantly decreased total protein (P<0.001), albumin (P=0.001), alpha-2 fraction (P<0.001), beta-2 fraction (P=0.004), and gamma fraction (P<0.001) but had no significant effects on alpha-1 and beta-1 fractions. Dietary GM inhibited/suppressed the effects of dietary OTC on the plasma total protein and protein fractions. In conclusion, adding 1% GM to diet can mitigate the negative effects of dietary OTC on plasma proteins. Thus, GM may boost health of rainbow trout during the period of medication with OTC.

Keywords: ginger, plasma protein electrophoresis, dietary additive, rainbow trout

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963 Chemical Leaching of Metals from Landfill’s Fine Fraction

Authors: E. Balkauskaitė, A. Bučinskas, R. Ivanauskas, M. Kriipsalu, G. Denafas

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Leaching of heavy metals (chromium, zinc, copper) from the fine fraction of the Torma landfill (Estonia) was investigated. The leaching kinetics studies have determined the dependence of some metal’s concentration on the leaching time. Metals were leached with Aqua Regia, distilled water and EDTA (Ethylenediaminetetraacetic acid); process was most intensive 2 hours after the start of the experiment, except for copper with EDTA (0.5 h) and lead with EDTA (4 h). During leaching, steady concentrations of Fe, Mn, Cd and Pb were fully stabilized after 8 h; however concentrations of Cu and Ni were not stabilized after 10 h.

Keywords: fine fraction, landfills, leached metals, leaching kinetics

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962 Hepatoprotective Effect of Ethyl Acetate Fraction of Ficus carica L. Leaves against Carbon Tetrachloride-Induced Toxicity in vitro and in vivo

Authors: Syeda Hira, Muhammad Gulfraz

Abstract:

Background: Liver diseases cause serious health issues. Plants contain active compounds that significantly help in the treatment of various diseases. Ficus carica is traditionally used for the treatment of liver diseases. The purpose of the present study was the isolation and identification of active components from F.carica leaves which are responsible for hepatoprotective activity. Methods: The study was designed to identify the most active hepatoprotective sub-fraction from ethyl acetate fraction of Ficus carica by in vitro study and evaluation of its in vivo hepatoprotective effect in animal models. Ethyl acetate fraction was subjected to column, and a total of eight sub-fractions were obtained. In vitro, the hepatoprotective effect of all sub-fractions was determined on HepG2 cell lines. Toxicity was induced by CCl₄ (Carbon tetrachloride), and silymarin was used as a positive control. On the basis of the results, the most active sub-fraction was subjected to LC-MS and FT-IR analysis for the identification of bioactive compounds. In vivo, the hepatoprotective effect was determined in mice. Toxicity was induced by CCl₄; at the end of the experiment, biochemical parameters such as ALT, AST, ALP, bilirubin, and total protein were estimated in serum. Histopathology of liver tissues was also done. Results: Sub-fraction FVI exhibited significant (P<0.05) hepatoprotective activity as compared to other sub-fractions, which was almost similar to the standard drug silymarin. Six known bioactive compounds were identified from this sub-fraction after LC-MS analysis. In vivo, the hepatoprotective activity of sub-fraction FVI was evaluated in CCl₄-induced toxicated mice. Administration of CCl₄ significantly increased level of ALT (Alanine transaminase), AST (Aspartate aminotransferase), ALP (Alkaline phosphatase), and bilirubin and decreased the total protein. Treatment with sub-fraction FVI significantly (p<0.05) reversed the level of these biomarkers toward normal at both doses of 25 mg/kg and 50 mg/kg. Conclusion: Our findings confirmed the hepatoprotective effect of ethyl acetate fraction of F.carica. It could be a good candidate for the development of a natural hepatoprotective drug; pre-clinical investigation on ethyl acetate fraction is recommended.

Keywords: Ficus carica, hepatoprotective, CCl₄, bioactive compounds, liver markers

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961 Profiling, Antibacterial and Antioxidant Activity of Acacia decurrens (Willd) an Invasive South Africa Tree

Authors: Joe Modise, Bamidel Joseph Okoli, Nas Molefe, Imelda Ledwaba

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The present study describes the chemical profile and antioxidant potential of the stem bark of Acacia decurrens. The methanol fraction of A. decurrens stem bark gave the highest yield (20 %), while the hexane fraction had the lowest yield (0.2 %). The GC-MS spectra of the hexane, chloroform and ethyl acetate fractions confirm the presence of fifty two major compounds and the ICP-OES analysis of the stem bark was found to contain Co(0.41), Zn(1.75), Mn(3.69), Ca(8.67), Ni(10.54), Mg(12.98), Cr(24.38), K(47.88), Fe(154.62) ppm; which is an indication of hyper-accumulation capacity. The UV-Visible spectra of showed four absorption maxima for hexane fraction at 665 (0.028), 410 (0.116), 335 (0.278) and 250 (0.007) nm, three for chloroform fraction at 665 (0.028), 335 (0.278) and 250 (0.007) nm , three for ethyl acetate fraction at 665 (0.070), 390 (0.648) and 345 (0.663) nm and three for methanol fraction at 385 (0.508), 310 (0.886) and 295 (0.899) nm respectively. Quantitative phytochemical screening indicated that the alkaloid (0.6-3.3) % and saponins (5.1-8.6) % contents of the various fractions were significantly lower than the tannin (30.9-55.8) mg TAE/g, steroid(13.92-41.2) %, phenol (40.6-65.5) mgGAE/g and flavonoids (210.2 -284.9) mg RUE/g contents. The antioxidant activity of the fractions was analysed by different methods and revealed good to moderate antioxidant potential with different IC50 values viz. (42.2-49.6) mg/mL for ABTS and (37.8-75.0) μg/ml for DPPH respectively, compared to standard antioxidants. Based on obtained results, the A.decurrens stem bark fractions can be a source of safe, sustainable natural antioxidant drug and can be exploited as a source of controlled green-heavy metal cleaner.

Keywords: Acacia decurrens, antioxidant, DPPH, ABTS, hyperaccumulation, Menstruum, ICP-OES, GC-MS, UV/visible

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960 Thick Disc Molecular Gas Fraction in NGC 6946

Authors: Narendra Nath Patra

Abstract:

Several recent studies reinforce the existence of a thick molecular disc in galaxies along with the dynamically cold thin disc. Assuming a two-component molecular disc, we model the disc of NGC 6946 as a four-component system consists of stars, HI, thin disc molecular gas, and thick disc molecular gas in vertical hydrostatic equilibrium. Following, we set up the joint Poisson-Boltzmann equation of hydrostatic equilibrium and solve it numerically to obtain a three-dimensional density distribution of different baryonic components. Using the density solutions and the observed rotation curve, we further build a three-dimensional dynamical model of the molecular disc and consecutively produce simulated CO spectral cube and spectral width profile. We find that the simulated spectral width profiles distinguishably differs for different assumed thick disc molecular gas fraction. Several CO spectral width profiles are then produced for different assumed thick disc molecular gas fractions and compared with the observed one to obtain the best fit thick disc molecular gas fraction profile. We find that the thick disc molecular gas fraction in NGC 6946 largely remains constant across its molecular disc with a mean value of 0.70 +/- 0.09. We also estimate the amount of extra-planar molecular gas in NGC 6946. We find 60% of the total molecular gas is extra-planar at the central region, whereas this fraction reduces to ~ 35% at the edge of the molecular disc. With our method, for the first time, we estimate the thick disc molecular gas fraction as a function of radius in an external galaxy with sub-kpc resolution.

Keywords: galaxies: kinematics and dynamic, galaxies: spiral, galaxies: structure , ISM: molecules, molecular data

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959 The Influence of Fiber Volume Fraction on Thermal Conductivity of Pultruded Profile

Authors: V. Lukášová, P. Peukert, V. Votrubec

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Thermal conductivity in the x, y and z-directions was measured on a pultruded profile that was manufactured by the technology of pulling from glass fibers and a polyester matrix. The results of measurements of thermal conductivity showed considerable variability in different directions. The caused variability in thermal conductivity was expected due fraction variations. The cross-section of the pultruded profile was scanned. An image analysis illustrated an uneven distribution of the fibers and the matrix in the cross-section. The distribution of these inequalities was processed into a Voronoi diagram in the observed area of the pultruded profile cross-section. In order to verify whether the variation of the fiber volume fraction in the pultruded profile can affect its thermal conductivity, the numerical simulations in the ANSYS Fluent were performed. The simulation was based on the geometry reconstructed from image analysis. The aim is to quantify thermal conductivity numerically. Above all, images with different volume fractions were chosen. The results of the measured thermal conductivity were compared with the calculated thermal conductivity. The evaluated data proved a strong correlation between volume fraction and thermal conductivity of the pultruded profile. Based on presented results, a modification of production technology may be proposed.

Keywords: pultrusion profile, volume fraction, thermal conductivity, numerical simulation

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958 Antimicrobial Activity of Ilex paraguariensis Sub-Fractions after Liquid-Liquid Partitioning

Authors: Sabah El-Sawalhi, Elie Fayad, Roula M. Abdel-Massih

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Ilex paraguariensis (Yerba Mate) is a medium to large tree commonly consumed by South Americans. Its leaves and stems are associated with different biological activities. The purpose of this study was to evaluate the antibacterial activity of Yerba Mate against Gram-positive and Gram-negative bacterial strains and its action against some resistant bacteria with different resistance profiles. Yerba Mate aqueous extracts were prepared at 70°C for 2 hrs, and the microdilution method was used to determine the minimum inhibitory concentration (MIC). Gram-positive bacteria exhibited a stronger antibacterial activity (MIC ranged between 0.468 mg/mL and 15 mg/mL) than Gram-negative bacteria. Yerba Mate was also extracted with acetone: water (1:1) and then further sub-fractionated with hexane, chloroform, and ethyl acetate. MIC values against Staphylococcus aureus ranged from 0.78 to 2.5 mg/ml for the chloroform fraction, from 1.56 to 3.75 mg/ml for the ethyl acetate fraction, and 0.78 to 1.87 mg/ml for the water fraction. The water fraction also exhibited antibacterial activity against Salmonella species (MIC ranged from 1.56 mg/ml to 3.12 mg/ml). The water fraction exhibited the highest antibacterial activity among all the fractions obtained. More studies are needed to determine the molecule or molecules responsible for this activity.

Keywords: antibacterial activity, bacterial resistance, minimum inhibitory concentration, yerba mate

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957 Analysis of Caffeic Acid from Myrica nagi Leaves by High Performance Liquid Chromatography

Authors: Preeti Panthari, Harsha Kharkwal

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Myrica nagi belongs to Myricaceae family. It is known for its therapeutic use since ancient times. The leaves were extracted with methanol and further fractioned with different solvents with increasing polarity. The n-butanol fraction of methanol extract was passed through celite, on separation through silica gel column chromatography yielded ten fractions. For the first time we report isolation of Caffeic acid from n-butanol fraction of Myrica nagi leaves in Chloroform: methanol (70:30) fraction. The mobile phase used for analysis in HPLC was Methanol: water (60:40) at the flow rate of 1 ml/min at wavelength of 280 nm. The retention time was 2.66 mins.

Keywords: Myrica nagi, column chromatography, retention time, caffeic acid

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956 Semiautomatic Calculation of Ejection Fraction Using Echocardiographic Image Processing

Authors: Diana Pombo, Maria Loaiza, Mauricio Quijano, Alberto Cadena, Juan Pablo Tello

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In this paper, we present a semi-automatic tool for calculating ejection fraction from an echocardiographic video signal which is derived from a database in DICOM format, of Clinica de la Costa - Barranquilla. Described in this paper are each of the steps and methods used to find the respective calculation that includes acquisition and formation of the test samples, processing and finally the calculation of the parameters to obtain the ejection fraction. Two imaging segmentation methods were compared following a methodological framework that is similar only in the initial stages of processing (process of filtering and image enhancement) and differ in the end when algorithms are implemented (Active Contour and Region Growing Algorithms). The results were compared with the measurements obtained by two different medical specialists in cardiology who calculated the ejection fraction of the study samples using the traditional method, which consists of drawing the region of interest directly from the computer using echocardiography equipment and a simple equation to calculate the desired value. The results showed that if the quality of video samples are good (i.e., after the pre-processing there is evidence of an improvement in the contrast), the values provided by the tool are substantially close to those reported by physicians; also the correlation between physicians does not vary significantly.

Keywords: echocardiography, DICOM, processing, segmentation, EDV, ESV, ejection fraction

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955 Numerical Study of Natural Convection of a Localized Heat Source at the up of a Nanofluid-Filled Enclosure

Authors: Marziyeh Heydari, Hossein Shokouhmand

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This article presents a numerical study of natural convection of a heat source embedded on the up wall of an enclosure filled with nanofluid. The bottom and vertical walls of the enclosure are maintained at a relatively low temperature. The type of nanofluid and solid volume fraction of nanoparticle on the heat transfer performance is studied. The results indicated that adding nanoparticle into pure paraffin improves heat transfer. The results are presented over a wide range of Rayleigh numbers(Ra=〖10〗^3 〖-10〗^5), the volume fraction of nanoparticles (0≤ɸ≤0.4%). For an enclosure, the Nusselt number of a cu-paraffin nanofluid was reduced by increasing the volume fraction of nanoparticles above 0.2%.

Keywords: nanofluid, heat transfer, heat source, enclosure

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954 Analysis of Air-Water Two-Phase Flow in a 3x3 Rod Bundle

Authors: Pei-Syuan Ruan, Ya-Chi Yu, Shao-Wen Chen, Jin-Der Lee, Jong-Rong Wang, Chunkuan Shih

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This study investigated the void fraction characteristics under low superficial gas velocity (Jg) and low superficial fluid velocity (Jf) conditions in a 3x3 rod bundle geometry. Three arrangements of conductivity probes were set to measure the void fraction at various cross-sectional regions, including rod-gap, sub-channel and rod-wall regions. The experimental tests were performed under the flow conditions of Jg = 0-0.236 m/s and Jf = 0-0.142 m/s, and the time-averaged void fractions were recorded at each flow condition. It was observed that while the superficial gas velocity increases, the small bubbles started to cluster together and become big bubbles. As the superficial fluid velocity increases, the local void fractions of the three test regions will get closer and the bubble distribution will be more uniform across the cross section.

Keywords: conductivity probes, rod bundles, two-phase flow, void fraction

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953 One Dimensional Reactor Modeling for Methanol Steam Reforming to Hydrogen

Authors: Hongfang Ma, Mingchuan Zhou, Haitao Zhang, Weiyong Ying

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One dimensional pseudo-homogenous modeling has been performed for methanol steam reforming reactor. The results show that the models can well predict the industrial data. The reactor had minimum temperature along axial because of endothermic reaction. Hydrogen productions and temperature profiles along axial were investigated regarding operation conditions such as inlet mass flow rate and mass fraction of methanol, inlet temperature of external thermal oil. Low inlet mass flow rate of methanol, low inlet temperature, and high mass fraction of methanol decreased minimum temperature along axial. Low inlet mass flow rate of methanol, high mass fraction of methanol, and high inlet temperature of thermal oil made cold point forward. Low mass fraction, high mass flow rate, and high inlet temperature of thermal oil increased hydrogen production. One dimensional models can be a guide for industrial operation.

Keywords: reactor, modeling, methanol, steam reforming

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952 Chemical Oxygen Demand Fractionation of Primary Wastewater Effluent for Process Optimization and Modelling

Authors: Thandeka Y. S. Jwara, Paul Musonge

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Traditionally, the complexity associated with implementing and controlling biological nutrient removal (BNR) in wastewater works (WWW) has been primarily in terms of balancing competing requirements for nitrogen and phosphorus removal, particularly with respect to the use of influent chemical oxygen demand (COD) as a carbon source for the microorganisms. Successful BNR optimization and modelling using WEST (Worldwide Engine for Simulation and Training) depend largely on the accurate fractionation of the influent COD. The different COD fractions have differing effects on the BNR process, and therefore, the influent characteristics need to be well understood. This study presents the fractionation results of primary wastewater effluent COD at one of South Africa’s wastewater works treating 65ML/day of mixed industrial and domestic effluent. The method used for COD fractionation was the oxygen uptake rate/respirometry method. The breakdown of the results of the analysis is as follows: 70.5% biodegradable COD (bCOD) and 29.5% of non-biodegradable COD (iCOD) in terms of the total COD. Further fractionation led to a readily biodegradable soluble fraction (SS) of 75%, a slowly degradable particulate fraction (XS) of 24%, a particulate non-biodegradable fraction (XI) of 50.8% and a non-biodegradable soluble fraction (SI) of 49.2%. The fractionation results demonstrate that the primary effluent has good COD characteristics, as shown by the high level of the bCOD fraction with Ss being higher than Xs. This means that the microorganisms have sufficient substrate for the BNR process and that these components can now serve as inputs to the WEST Model for the plant under study.

Keywords: chemical oxygen demand, COD fractionation, wastewater modelling, wastewater optimization

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951 Tracking of Linarin from the Ethyl Acetate Fraction of Melinjo (Gnetum gnemon L.) Seeds Using Preparative High Performance Liquid Chromatography

Authors: Asep Sukohar, Ramadhan Triyandi, Muhammad Iqbal, Sahidin, Suharyani

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Introduction: Resveratrol is a class of bioactive chemicals found in melinjo, which has a wide range of biological actions. The purpose of this study is to determine the linarin content of the melinjo fraksi by using preparative-high-performance liquid chromatography (prep-HPLC). Method: Extraction used the soxhletation method with 96% ethanol solvent. Fractionation used ethyl acetate and ethanol in a ratio of 1:1. Tracing of linarin compound used prep-HPLC with a mobile phase ratio of distilled water: methanol (55: 45, v/v). The presence of linarin was detected using a wavelength of 215 nm. Fourier Transform Infrared (FTIR) was used to identify the functional groups of compound. Result: The retention time required to elute the ethyl acetate fraction was 2.601 minutes. Compound separation identification using Fourier Transform Infrared Spectroscopy - Quest Attenuated Total Reflectance (FTIR - QATR) has a similarity value range with standards from 0 to 1000. The elution results of the ethyl acetate fraction have similar values with the standard compounds linarin (668), resveratrol (578), and catechin (455). Conclusion: Tracing for active compound in the ethyl acetate fraction of Gnetum Gnemon L. using prep-HPLC showed a strong suspicion of the presence of linarin compound.

Keywords: Gnetum gnemon L., linarin, prep-HPLC, fraction ethyl acetate

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950 Antimutagenic Activity of a Protein, Lectin Fraction from Urtica Dioica L.

Authors: Nijole Savickiene, Antonella Di Sotto, Gabriela Mazzanti, Rasa Starselskyte, Silvia Di Giacomo, Annabella Vitalone

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Plant lectins are non-enzymic and non-immune origin proteins that specifically recognize and bind to various sugar structures and possess the activity to agglutinate cells and/or precipitate polysaccharides and glycoconjugates. The emerging evidences showed that plant lectins contribute not only to tumour cell recognition but also to cell adhesion and localization, to signal transduction, to mitogenic cytotoxicity and apoptosis. Among chitin-binding lectins, the Urtica dioica agglutinin (UDA), which is a complex of different isoforms, has been poorly studied for its biological activity. In this context and according to the increasing interest for lectins as novel antitumor drugs, present paper aimed at evaluating the potential antimutagenic activity of a lectin-like glycoprotein-enriched fraction from aerial part of Urtica dioica L. Aim: to evaluate the potential chemopreventive properties of a protein - lectin fraction from the aerial part of Urtica dioica. Materials and methods: Protein – lectin fraction has been tested for the antimutagenic activity in bacteria (50–800 mg/plate; Ames test by the preincubation method) and for the cytotoxicity on human hepatoma HepG2 cells (0.06–2 mg/mL; 24 and 48 h incubation). Results: Protein – lectin fraction from stinging nettle was not cytotoxic on HepG2 cells up to 2 mg/mL; conversely, it exhibited a strong antimutagenic activity against the mutagen 2-aminoanthracene (2AA) in all strains tested (maximum inhibition of 56.78 and 61% in TA98, TA100, and WP2uvrA strains, respectively, at 800 mg/plate). Discussion and conclusions: Protein – lectin fraction from Urtica dioica L. possesses antimutagenic and radical scavenging properties. Being 2AA a pro-carcinogenic agent, we hypothesize that the antimutagenicity of it can be due to the inhibition of CYP450-isoenzymes, involved in the mutagen bioactivation.

Keywords: lectins, antimutagenicity, chemoprevention, Urtica dioica

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949 Efficacy of Heart Failure Reversal Treatment Followed by 90 Days Follow up in Chronic Heart Failure Patients with Low Ejection Fraction

Authors: Rohit Sane, Snehal Dongre, Pravin Ghadigaonkar, Rahul Mandole

Abstract:

The present study was designed to evaluate efficacy of heart failure reversal therapy (HFRT) that uses herbal procedure (panchakarma) and allied therapies, in chronic heart failure (CHF) patients with low ejection fraction. Methods: This efficacy study was conducted in CHF patients (aged: 25-65 years, ejection fraction (EF) < 30%) wherein HFRT (60-75 minutes) consisting of snehana (external oleation), swedana (passive heat therapy), hrudaydhara(concoction dripping treatment) and basti(enema) was administered twice daily for 7 days. During this therapy and next 30 days, patients followed the study dinarcharya and were prescribed ARJ kadha in addition to their conventional treatment. The primary endpoint of this study was evaluation of maximum aerobic capacity uptake (MAC) as assessed by 6-minute walk distance (6MWD) using Cahalins equation from baseline, at end of 7 day treatment, follow-up after 30 days and 90 days. EF was assessed by 2D Echo at baseline and after 30 days of follow-up. Results: CHF patients with < 30% EF (N=52, mean [SD] age: 58.8 [10.8], 85% men) were enrolled in the study. There was a 100% compliance to study therapy. A significant improvement was observed in MAC levels (7.11%, p =0.029), at end of 7 day therapy as compared to baseline. This improvement was maintained at two follow-up visits. Moreover, ejection fraction was observed to be increased by 6.38%, p=0,012 as compared to baseline at day 7 of the therapy. Conclusions: This 90 day follow up study highlights benefit of HFRT, as a part of maintenance treatment for CHF patients with reduced ejection fraction.

Keywords: chronic heart failure, functional capacity, heart failure reversal therapy, oxygen uptake, panchakarma

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948 Computational Fluid Dynamics Modeling of Flow Properties Fluctuations in Slug-Churn Flow through Pipe Elbow

Authors: Nkemjika Chinenye-Kanu, Mamdud Hossain, Ghazi Droubi

Abstract:

Prediction of multiphase flow induced forces, void fraction and pressure is crucial at both design and operating stages of practical energy and process pipe systems. In this study, transient numerical simulations of upward slug-churn flow through a vertical 90-degree elbow have been conducted. The volume of fluid (VOF) method was used to model the two-phase flows while the K-epsilon Reynolds-Averaged Navier-Stokes (RANS) equations were used to model turbulence in the flows. The simulation results were validated using experimental results. Void fraction signal, peak frequency and maximum magnitude of void fraction fluctuation of the slug-churn flow validation case studies compared well with experimental results. The x and y direction force fluctuation signals at the elbow control volume were obtained by carrying out force balance calculations using the directly extracted time domain signals of flow properties through the control volume in the numerical simulation. The computed force signal compared well with experiment for the slug and churn flow validation case studies. Hence, the present numerical simulation technique was able to predict the behaviours of the one-way flow induced forces and void fraction fluctuations.

Keywords: computational fluid dynamics, flow induced vibration, slug-churn flow, void fraction and force fluctuation

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947 Influence of Flame-Holder on Existence Important Parameters in a Duct Combustion Simulator

Authors: Mohammad Mahdi Doustdar, Mohammad Mojtahedpoor

Abstract:

The effects of flame-holder position, the ratio of flame holder diameter to combustion chamber diameter and injection angle on fuel propulsive droplets sizing and effective mass fraction have been studied by a cold flow. We named the mass of fuel vapor inside the flammability limit as the effective mass fraction. An empty cylinder as well as a flame-holder which are as a simulator for duct combustion has been considered. The airflow comes into the cylinder from one side and injection operation will be done by four nozzles which are located on the entrance of cylinder. To fulfill the calculations a modified version of KIVA-3V code which is a transient, three-dimensional, multi phase, multi component code for the analysis of chemically reacting flows with sprays, is used.

Keywords: KIVA-3V, flame-holder, duct combustion, effective mass fraction, mean diameter of droplets

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946 Stabilization of Soil Organic Carbon within Silt+Clay Fraction in Shrub-Encroached Rangeland Shallow Soil at the University of Limpopo Syferkuil Experimental Farm

Authors: Millicent N. Khumalo, Phesheya E. Dlamini

Abstract:

Shrub-encroachment leads to a gain or loss of soil organic carbon (SOC) in previously open rangelands. The stabilization mechanisms controlling the storage of soil organic carbon (SOC) within aggregates of shrub-encroached grassland soils are poorly understood, especially in shallow plinthic soils. In this study, physical fractionation of surface soils (0- 10 cm) collected from open and shrub-encroached grasslands was conducted to determine the distribution of SOC within macro-and- microaggregates. Soil aggregates were classified into four fractions by a wet-sieving procedure, namely >2000 (large macro-aggregates), 212-2000 (small macro-aggregates), 50-212 (microaggregates) and < 50µm (silt+clay). In both shrub-encroached and open grassland soils, SOC was greater in the silt+clay fraction. In this fraction, SOC was on average 133% greater in shrub-encroached compared to open grassland. The greater SOC within the silt+clay fraction is due to the greater surface area and thus more exchange sites for carbon absorption. This implies that the SOC physically protected within the silt+clay is stored long-term.

Keywords: aggregate fractions, shrub-encroachment, soil organic carbon, stabilization

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945 Chemical Partitioning of Trace Metals in Sub-Surface Sediments of Lake Acigol, Denizli, Turkey

Authors: M. Budakoglu, M. Karaman, D. Kiran, Z. Doner, B. Zeytuncu, B. Tanç, M. Kumral

Abstract:

Lake Acıgöl is one of the large saline lacustrine environment in Turkey. Eleven trace metals (Cr, Mn, Fe, Al, Co, Ni, Cu, Zn, Cd, Pb and As) in 9 surface and subsurface sediment samples from the Lake Acıgöl were analyzed with the bulk and sequential extraction analysis methods by ICP-MS to obtain the metal distribution patterns in this extreme environment. Five stepped sequential extraction technique (1- exchangeable, 2- bond to carbonates, 3- bond to iron and manganese oxides/hydroxides, 4- bond to organic matter and sulphides, and 5- residual fraction incorporated into clay and silicate mineral lattices) was used to characterize the various forms of metals in the <63μ size sediments. The metal contents (ppm) and their percentages for each extraction step were reported and compared with the results obtained from the total digestion. Results indicate that sum of the four fraction are in good agreement with the total digestion results of Ni, Cd, As, Zn, Cu and Fe with the satisfactory recoveries (94.04–109.0%) and the method used is reliable and repeatable for these elements. It was found that there were high correlations between Fe vs. Ni loads in the fraction of F2 and F4 with R2= 0,91 and 0,81, respectively. Comparison of totally 135 chemical analysis results in three sampling location and for 5 fraction between Fe-Co, Co-Ni and Fe-Ni element couples were presented elevated correlations with R2=0,98, 0,92 and 0,91, respectively.

Keywords: Lake Acigol, sequancial extraction, recent lake sediment, geochemical speciation of heavy metals

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944 Determination of in vitro Antioxidative Activity of Aster yomena (Kitam.) Honda

Authors: Hyun Young Kim, Min Jung Kim, Ji Hyun Kim, Sanghyun Lee, Eun Ju Cho

Abstract:

Oxidative stress that results from overproduction of free radicals can lead to pathogenesis of human diseases including cancer, neurodegenerative diseases, and cardiovascular disease. Aster yomena (Kitam.) Honda (A. yomena) belonging to Compositae family is a perennial plant, and it has anti-inflammatory, anti-asthmatic and anti-obesity effects. In this study, we investigated the antioxidative effect of A. yomena by measuring 2, 2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical (˙OH) and superoxide radical (O₂⁻) scavenging activities in vitro. A. yomena was extracted with ethanol and then partitioned with n-hexane, methylene chloride (CH₂Cl₂), ethyl acetate (EtOAc) and n-butanol (n-BuOH). In DPPH radical scavenging assay, the concentration of A. yomena from 10 to 100μg/mL dose-dependently raised the inhibition of DPPH oxidation. Especially, EtOAc fraction of A. yomena showed the highest DPPH radical scavenging activity among other fractions. The ˙OH radical scavenging activities of the extract and four fractions of A. yomena were increased by over 80% at a concentration of 50μg/mL. Especially, the IC50 value of EtOAc fraction was 0.03 μg/mL that is the lowest value compared with the values of other fractions. In addition, we found that the EtOAc fraction of A. yomena was showed to be better at O₂⁻ radical scavenging than other fractions. Taken together these results, we suggested that A. yomena, especially EtOAc fraction, can be used as a natural antioxidant against free radicals. Acknowledgements: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF-2016R1D1A1B03931593).

Keywords: Aster yomena (Kitam.) Honda (A. yomena), free radicals, antioxidant, EtOAc fraction

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943 Characterisation of Fractions Extracted from Sorghum Byproducts

Authors: Prima Luna, Afroditi Chatzifragkou, Dimitris Charalampopoulos

Abstract:

Sorghum byproducts, namely bran, stalk, and panicle are examples of lignocellulosic biomass. These raw materials contain large amounts of polysaccharides, in particular hemicelluloses, celluloses, and lignins, which if efficiently extracted, can be utilised for the development of a range of added value products with potential applications in agriculture and food packaging sectors. The aim of this study was to characterise fractions extracted from sorghum bran and stalk with regards to their physicochemical properties that could determine their applicability as food-packaging materials. A sequential alkaline extraction was applied for the isolation of cellulosic, hemicellulosic and lignin fractions from sorghum stalk and bran. Lignin content, phenolic content and antioxidant capacity were also investigated in the case of the lignin fraction. Thermal analysis using differential scanning calorimetry (DSC) and X-Ray Diffraction (XRD) revealed that the glass transition temperature (Tg) of cellulose fraction of the stalk was ~78.33 oC at amorphous state (~65%) and water content of ~5%. In terms of hemicellulose, the Tg value of stalk was slightly lower compared to bran at amorphous state (~54%) and had less water content (~2%). It is evident that hemicelluloses generally showed a lower thermal stability compared to cellulose, probably due to their lack of crystallinity. Additionally, bran had higher arabinose-to-xylose ratio (0.82) than the stalk, a fact that indicated its low crystallinity. Furthermore, lignin fraction had Tg value of ~93 oC at amorphous state (~11%). Stalk-derived lignin fraction contained more phenolic compounds (mainly consisting of p-coumaric and ferulic acid) and had higher lignin content and antioxidant capacity compared to bran-derived lignin fraction.

Keywords: alkaline extraction, bran, cellulose, hemicellulose, lignin, stalk

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942 Evaluation of the Anti Ulcer Activity of Ethyl Acetate Fraction of Methanol Leaf Extract of Clerodendrum Capitatum

Authors: M. N. Ofokansi, Onyemelukwe Chisom, Amauche Chukwuemeka, Ezema Onyinye

Abstract:

The leaves of Clerodendrumcapitatum(Lamiaceae) is mostly used in the treatment of gastric ulcer in Nigerian folk medicine. The aim of this study was to evaluate the antiulcer activity of its crude methanol leaf extract and its ethyl acetate fraction in white albino rats. The effect of crude methanol leaf extract and its ethyl acetate fraction(250mg/kg, 500mg/kg) was evaluated using an absolute ethanol induced ulcer model. Crude methanol leaf extract and the ethyl acetate fraction was treated with distilled water and 6% Tween 80, respectively. crude methanol leaf extract was further investigated using a pylorus ligation induced ulcer model. Omeprazole was used as the standard treatment. Four groups of five albino rats of either sex were used. Parameters such as mean ulcer index and percentage ulcer protection were assessed in the ethanol-induced ulcer model, while the gastric volume, pH, and total acidity were assessed in the pyloric ligation induced ulcer model. Crude methanol leaf extract of Clerodendrumcapitatum(500mg/kg) showed a very highly significant reduction in mean ulcer index(p<0.001) in the absolute ethanol-induced model. ethyl acetate fraction of crude methanol leaf extract of Clerodendrumcapitatum(250mg/kg,500mg/kg) showed a very highly significant dose-dependent reduction in mean ulcer indices (p<0.001) in the absolute ethanol-induced model. The mean ulcer indices (1.6,2.2) with dose concentration (250mg/kg, 500mg/kg) of ethyl acetate fraction increased with ulcer protection (82.85%,76.42%) respectively when compared to the control group in the absolute ethanol-induced ulcer model. Crude methanol leaf extract of Clerodendrumcapitatum(250mg/kg, 500mg/kg) treated animals showed a highly significant dose-dependent reduction in mean ulcer index(p<0.01) with an increase in ulcer protection (56.77%,63.22%) respectively in pyloric ligated induced, ulcer model. Gastric parameters such as volume of gastric juice, pH, and total acidity were of no significance in the different doses of the crude methanol leaf extract when compared to the control group. The phytochemical investigation showed that the crude methanol leaf extracts Possess Saponins and Flavonoids while its ethyl acetate fraction possess only Flavonoids. The results of the study indicate that the crude methanol leaf extract and its ethyl acetate fraction is effective and has gastro protective and ulcer healing capacity. Ethyl acetate fraction is more potent than crude methanol leaf extract against ethanol-induced This result provides scientific evidence as a validation for its folkloric use in the treatment of gastric ulcer.

Keywords: gastroprotective, herbal medicine, anti-ulcer, pharmacology

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