Academy of Graduate Studies

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Bejarpas O.F.,Academy of Pedagogical Graduate | Soleimani S.,Academy of Graduate Studies
NeuroQuantology | Year: 2017

The aim of present research is to determining Psychological Features of delinquent boys and girls in comparison to other non-delinquent groups. In doing this 120 delinquent individuals (60 boys and 60 girls) were compared with SCL-90-R after equalizing. Findings showed that delinquent boys manifest significant differences in all different aspects of depression, physical complains, obsession, persistence, anxiety, sensitivity in inter-personal relationship, psychosis, paranoid thoughts, aggression, phobia. Delinquent girls, also, in different aspect of study, like anxiety and physical complain received higher marks in compare with their similar group. © 2017, E-FLOW PDF NeuroQuantology. All rights reserved.


Sibi G.,Academy of Graduate Studies | Rabina S.,Academy of Graduate Studies
Pharmacognosy Research | Year: 2016

Objective: The aim of this study was to determine the in vitro anti-inflammatory activities of solvent fractions from Chlorella vulgaris by inhibiting the production of pro-inflammatory mediators and cytokines. Methods: Methanolic extracts (80%) of C. vulgaris were prepared and partitioned with solvents of increasing polarity viz., n-hexane, chloroform, ethanol, and water. Various concentrations of the fractions were tested for cytotoxicity in RAW 264.7 cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, and the concentrations inducing cell growth inhibition by about 50% (IC50) were chosen for further studies. Lipopolysaccharide (LPS) stimulated RAW 264.7 cells were treated with varying concentrations of C. vulgaris fractions and examined for its effects on nitric oxide (NO) production by Griess assay. The release of prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) were quantified using enzyme-linked immunosorbent assay using Celecoxib and polymyxin B as positive controls. Results: MTT assay revealed all the solvent fractions that inhibited cell growth in a dose-dependent manner. Of all the extracts, 80% methanolic extract exhibited the strongest anti-inflammatory activity by inhibiting NO production (P < 0.01), PGE2 (P < 0.05), TNF-α, and IL-6 (P < 0.001) release in LPS induced RAW 264.7 cells. Both hexane and chloroform fractions recorded a significant (P < 0.05) and dose-dependent inhibition of LPS induced inflammatory mediators and cytokines in vitro. The anti-inflammatory effect of ethanol and aqueous extracts was not significant in the study. Conclusion: The significant inhibition of inflammatory mediators and cytokines by fractions from C. vulgaris suggests that this microalga would be a potential source of developing anti-inflammatory agents and a good alternate for conventional steroidal and nonsteroidal anti-inflammatory drugs. © 2016 Pharmacognosy Research | Published by Wolters Kluwer - Medknow.


Elghali A.A.,Academy of Graduate Studies
2016 17th International Conference on Sciences and Techniques of Automatic Control and Computer Engineering, STA 2016 - Proceedings | Year: 2017

In this paper, the author has developed a new theoretical model called the Adaptive Learning and Thinking Style for E-learning System using Neural Network (ALTENN) model. Determining intangible human behavior such as preference or motional aspect is very difficult due to many factors featured in the person's personality, taste, gender, age, and mood. Therefore, determining individuals learning style especially for e-learning and finding the appropriate learning approach that a student prefers in his/her study is a very critical issue. Dealing with different students with different styles of thinking and learning is still the critical issue for most researches. This research presented ALTENN model to accommodate learner in convenient learning environment to improve adaptive e-learning system. Neural network technology has been used to predict the learner learning style based on his/her thinking style and the structure of the system has been developed. © 2016 IEEE.


Edreder E.A.,Libyan Petroleum Institute | Mujtaba I.M.,University of Bradford | Emtir M.M.,Academy of Graduate Studies
Chemical Engineering Transactions | Year: 2012

The middle vessel column (MVC) is a combination of a batch rectifier (conventional column) and a batch stripper (inverted column). Therefore it is possible to obtain a light and a heavy fraction simultaneously from the top and the bottom of the column while an intermediate fraction may also be recovered in the middle vessel. Several researchers in the past have proposed the esterification of lactic acid (impure) with alcohol to obtain lactate ester which is then separated by distillation. To the best of our knowledge, simulation of middle vessel batch reactive distillation column for hydrolysis system has not yet been explored. In this work, the hydrolysis reaction of methyl lactate to produce lactic acid (LA) is carried out in a middle vessel column with fixed batch time while control variables are treated as a piecewise constant reflux ratio (multiple time intervals) and a single reboil ratio. For MVC, the LA being the heaviest in the reaction mixture, reflux and reboil ratios policy plays an important role to achieve high purity of LA. Copyright © 2012, AIDIC Servizi S.r.l.


Edreder E.A.,Libyan Petroleum Institute | Mujtaba I.M.,University of Bradford | Emtir M.,Academy of Graduate Studies
Chemical Engineering Journal | Year: 2011

Hydrolysis of methyl lactate to lactic acid in a reactive distillation column is widely used in the purification of lactic acid. In this work, optimal operations of conventional and inverted batch reactive distillation columns undergoing the hydrolysis reaction are presented. Minimum time optimisation problem is formulated incorporating a process model within gPROMS software and is solved for different range of lactic acid purity and the amount of product using both columns. For a given column type and configuration the minimum operation time is obtained by optimising the reflux ratio profile. For conventional column, the lactic acid being the heaviest in the reaction mixture, reflux ratio policy plays an important role in removing the light product methanol from the top of the column while ensuring the presence of both reactants in the reaction zone to maximise the conversion to lactic acid. For inverted column, reboil ratio policy plays an important role in removing the lactic acid from the bottom of the column while ensuring the presence of both reactants in the reaction zone to maximise the conversion to lactic acid. For some cases (although limited) it is observed that for low lactic acid product purity the conventional column outperforms the inverted column while for high product purity the inverted column outperforms the conventional column in terms of batch time. © 2011 Elsevier B.V.


Sibi G.,Academy of Graduate Studies
Research Journal of Environmental Toxicology | Year: 2015

Autotrophic cultivation of microalgae induces low biomass and lipid production and is difficult to be used in pilot scale production. Heterotrophic and mixotrophic algae allows higher growth rate, which in turn can accumulate higher biomass and lipid. Enhanced biomass and lipid production is crucial to use oleaginous microalgae for industrial application of biodiesel production. A fresh water microalga was isolated from waste water treatment plant and identified as Scenedesmus obliquus. The isolate was grown under varying cultural and nutrient conditions to increase biomass and lipid production. For this purpose, CO2 (10-160 mL min-1), temperature (20-45°C), fructose, maltose, glucose, sucrose and starch (10-50 g L-1), urea, sodium nitrate, potassium nitrate, ammonium nitrate and ammonium chloride (0.2-1.0 g L-1) were used. Optimum conditions were found by calculating specific growth rate and used to determine their influence on biomass and lipid production. At 40 mL minG1 (0.51%) CO2 concentration, 18.17 g L-1 biomass and 64.2% lipid production was obtained from the isolate. Glucose at 20 g L-1 have produced 18.62 g L-1 and 62.6% whereas sodium nitrate at 0.8 g L-1 resulted in 14.64 g L-1 and 65.1% of biomass and lipid production at the end of 20 days culturing period. Temperature of 25°C was found optimum where 12.38 g L-1 and 60.9% of biomass and lipid were obtained. Based on the results, by choosing optimum cultural conditions and nutrient composition of the growth medium it is possible to increase both biomass and lipid production in microalgae. © 2015 Academic Journals Inc.


Mujtaba I.M.,University of Bradford | Edreder E.A.,Libyan Petroleum Institute | Emtir M.,Academy of Graduate Studies
Applied Energy | Year: 2012

Lactic acid is widely used as a raw material for the production of biodegradable polymers and in food, chemical and pharmaceutical industries. The global market for lactic acid is expected to reach 259 thousand metric tons by the year 2012. For batch production of lactic acid, the traditional process includes the following steps: (i) esterification of impure lactic acid with methanol in a batch reactor to obtain methyl lactate (ester), (ii) separation of the ester in a batch distillation, (iii) hydrolysis of the ester with water in a batch reactor to produce lactic acid and (iv) separation of lactic acid (in high purity) in a batch distillation. Batch reactive distillation combines the benefit of both batch reactor and batch distillation and enhances conversion and productivity (Taylor and Krishna, 2000 [1]; Mujtaba and Macchietto, 1997 [2]). Therefore, the first and the last two steps of the lactic acid production process can be combined together in batch reactive distillation (Fig. 1) processes. However, distillation (batch or continuous) is an energy intensive process and consumes large amount of thermal energy (via steam). This paper highlights how significant (over 50%) reduction in thermal energy consumption can be achieved for lactic acid production process by carefully controlling the reflux ratio but without compromising the product specification. In this paper, only the simultaneous hydrolysis of methyl lactate ester and the separation of lactic acid using batch reactive distillation is considered. © 2010 Elsevier Ltd.


Sibi G.,Academy of Graduate Studies
Journal of Environmental Science and Technology | Year: 2015

The aim of this study was to evaluate the hydrolysates from crop residues as low cost carbon and nitrogen source for algal cultivation. The enzymatic hydrolysates of sweet sorghum (SSH) and rice straw (RSH) were used for heterotrophic cultivation of Chlorella vulgaris and Scenedesmus obliquus. Sugar concentration of 36.5 and 30.3 g LG1 were obtained in SSH and RSH, whereas, the nitrogen content was 10.6 and 19.5 mg LG1. Basal media with glucose was used as control and hydrolysates medium was used alone and in combination to determine its efficiency on microalgal biomass and lipid production. Maximum biomass was achieved in combined hydrolysates medium in C. vulgaris (4.8 g LG1) followed by S. obliquus (4.3 g LG1). Total lipid content of Chlorella was ranged from 11.26-29.36 and 15.43-27.24% in Scenedesmus. The qualitative analysis of fatty acids showed very high values of stearic acid (28.41 and 31.01%) and palmitic acid (23.54 and 26.21%) in both microalgae. This study could establish that the hydrolysates from sweet sorghum stem and rice straw can be used as growth medium for microalgal cultivation and opens new possibilities of exploiting crop residues for industrial applications. © 2015 Asian Network for Scientific Information.


Elghawi U.M.,Academy of Graduate Studies | Mayouf A.M.,Ningbo University
Fuel | Year: 2014

The analysis of carbonyl species of a gasoline fuelled Spark-Ignition and Homogeneous Charge Compression Ignition (SI/HCCI) engine operating modes was performed upstream and downstream of a three way catalyst (TWC) converter. All data were obtained during steady-state, fully warmed-up operation at different engine conditions, using a winter grade commercial gasoline containing 2% w/w ethanol (C2H5OH). Qualitative and quantitative analysis of carbonyl compounds in exhaust gases were performed using 2,4- dinitrophenylhydrazine (DNPH)-high-performance liquid chromatography (HPLC). The major carbonyl compounds detected in the collected samples were acetaldehyde, acrolein, benzaldehyde and m-tolualdehyde. Depending on the engine operation conditions, the percentage contribution of the carbonyl compounds to the total hydrocarbons emission in this study lies between 2.7% and 5.2%. Formation of low molecular weight carbonyl compounds was more prominent when the engine operated at low load HCCI mode (low combustion temperature), while aromatic aldehydes were more significant in the case of SI mode operation, in which the combustion temperature is relatively high compared to the temperature from low load HCCI mode. Even though, the catalyst reduced the hydrocarbons emission effectively, including the carbonyls, there is no significant effect on the emission of acetaldehyde and acrolein emissions. © 2013 Elsevier Ltd. All rights reserved.


Balasubramanian K.,Academy of Graduate Studies | Balasubramanian K.,Tamil University | Padma P.R.,Tamil University
International Journal of Pharma and Bio Sciences | Year: 2012

Plants play an indispensable part in the environment, especially as a medication to protect man from intrinsic and extrinsic ill effects imparted by stress agents. In tune with the search of antioxidant-rich plants, the leaves of Zea mays were analyzed for its antioxidant potential at three different stages of growth. The effect of the leaf extract on the oxidant stress induced in in vitro systems, which simulated in vivo conditions, were studied. The in vitro model used as a means to replace or minimize the use of live animals in experiments was goat liver slices. The aim of the present study was to assess the extent of oxidative stress, the activities and levels of antioxidants by the extracts of Zea mays in the presence and absence of oxidative stress. Our findings suggest that the hepatoprotection by Zea mays leaves against hydrogen peroxide induced oxidative stress could be due to its antioxidant property.

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