Search results for: economic activity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2713

Search results for: economic activity

2443 Optimal Dynamic Economic Load Dispatch Using Artificial Immune System

Authors: I. A. Farhat

Abstract:

The The dynamic economic dispatch (DED) problem is one of the complex constrained optimization problems that have nonlinear, con-convex and non-smooth objective functions. The purpose of the DED is to determine the optimal economic operation of the committed units while meeting the load demand. Associated to this constrained problem there exist highly nonlinear and non-convex practical constraints to be satisfied. Therefore, classical and derivative-based methods are likely not to converge to an optimal or near optimal solution to such a dynamic and large-scale problem. In this paper, an Artificial Immune System technique (AIS) is implemented and applied to solve the DED problem considering the transmission power losses and the valve-point effects in addition to the other operational constraints. To demonstrate the effectiveness of the proposed technique, two case studies are considered. The results obtained using the AIS are compared to those obtained by other methods reported in the literature and found better.

Keywords: Artificial Immune System (AIS), Dynamic Economic Dispatch (DED).

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2442 Performance of Bio-Composite Carbonized Materials in Probiotic Applications

Authors: Irina S. Savitskaya, Aida S. Kistaubayeva, Nuraly S. Akimbekov, Ilya E. Digel, Azhar A. Zhubanova

Abstract:

A new composite sorbent based on carbonized rice husk (CRH) and immobilized on it living cells and inactivated cultural liquid containing antimicrobials metabolites of Bacillus subtilis CK-245 is developed. The sorption and antimicrobic activity of CRH concerning five species of Enterobacteriaceae is studied. Prospects of use of developed sorbent in medicine and veterinary science is shown.

Keywords: CRH, probiotic, concentrated fugate, sorption and antimicrobial activity.

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2441 Model Discovery and Validation for the Qsar Problem using Association Rule Mining

Authors: Luminita Dumitriu, Cristina Segal, Marian Craciun, Adina Cocu, Lucian P. Georgescu

Abstract:

There are several approaches in trying to solve the Quantitative 1Structure-Activity Relationship (QSAR) problem. These approaches are based either on statistical methods or on predictive data mining. Among the statistical methods, one should consider regression analysis, pattern recognition (such as cluster analysis, factor analysis and principal components analysis) or partial least squares. Predictive data mining techniques use either neural networks, or genetic programming, or neuro-fuzzy knowledge. These approaches have a low explanatory capability or non at all. This paper attempts to establish a new approach in solving QSAR problems using descriptive data mining. This way, the relationship between the chemical properties and the activity of a substance would be comprehensibly modeled.

Keywords: association rules, classification, data mining, Quantitative Structure - Activity Relationship.

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2440 Optimal Dynamic Economic Load Dispatch Using Artificial Immune System

Authors: I. A. Farhat

Abstract:

The dynamic economic dispatch (DED) problem is one of the complex constrained optimization problems that have nonlinear, con-convex and non-smooth objective functions. The purpose of the DED is to determine the optimal economic operation of the committed units while meeting the load demand.  Associated to this constrained problem there exist highly nonlinear and non-convex practical constraints to be satisfied. Therefore, classical and derivative-based methods are likely not to converge to an optimal or near optimal solution to such a dynamic and large-scale problem. In this paper, an Artificial Immune System technique (AIS) is implemented and applied to solve the DED problem considering the transmission power losses and the valve-point effects in addition to the other operational constraints. To demonstrate the effectiveness of the proposed technique, two case studies are considered. The results obtained using the AIS are compared to those obtained by other methods reported in the literature and found better.

Keywords: Artificial Immune System (AIS), Dynamic Economic Dispatch (DED).

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2439 Technical Support of Intracranial Single Unit Activity Measurement

Authors: Richard Grünes, Karel Roubik

Abstract:

The article deals with technical support of intracranial single unit activity measurement. The parameters of the whole measuring set were tested in order to assure the optimal conditions of extracellular single-unit recording. Metal microelectrodes for measuring the single-unit were tested during animal experiments. From signals recorded during these experiments, requirements for the measuring set parameters were defined. The impedance parameters of the metal microelectrodes were measured. The frequency-gain and autonomous noise properties of preamplifier and amplifier were verified. The measurement and the description of the extracellular single unit activity could help in prognoses of brain tissue damage recovery.

Keywords: Measuring set, metal microelectrodes, single-unit, noise, impedance parameters, gain characteristics.

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2438 Mathematical Model and Solution Algorithm for Containership Operation/Maintenance Scheduling

Authors: Hun Go, Ji-Su Kim, Dong-Ho Lee

Abstract:

This study considers the problem of determining operation and maintenance schedules for a containership equipped with components during its sailing according to a pre-determined navigation schedule. The operation schedule, which specifies work time of each component, determines the due-date of each maintenance activity, and the maintenance schedule specifies the actual start time of each maintenance activity. The main constraints are component requirements, workforce availability, working time limitation, and inter-maintenance time. To represent the problem mathematically, a mixed integer programming model is developed. Then, due to the problem complexity, we suggest a heuristic for the objective of minimizing the sum of earliness and tardiness between the due-date and the starting time of each maintenance activity. Computational experiments were done on various test instances and the results are reported.

Keywords: Containerships, operation and preventive maintenance schedules, integer programming, heuristic

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2437 Electroencephalography Activity during Sensory Organization Balance Test

Authors: Tariq Ali Gujar, Anita Hökelmann

Abstract:

Postural balance plays essential role throughout life in daily activities. Somatosensory, visual and vestibular inputs play the fundamental role in maintaining body equilibrium to balance the posture. The aim of this study was to find out electroencephalography (EEG) responses during balance activity of young people during Sensory Organization Balance Test. The outcome of this study will help to create the fitness and neurorehabilitation plan. 25 young people (25 ± 3.1 years) have been analyzed on Balance Master NeuroCom® with the coupling of Brain Vision 32 electrode wireless EEG system during the Sensory Organization Test. From the results it has been found that the balance score of samples is significantly higher under the influence of somatosensory input as compared to visual and vestibular input (p < 0.05). The EEG between somatosensory and visual input to balance the posture showed significantly higher (p < 0.05) alpha and beta activities during somatosensory input in somatosensory, attention and visual functions of the cortex whereas executive and motor functions of the cerebral cortex showed significantly higher (p < 0.05) alpha EEG activity during the visual input. The results suggest that somatosensory and attention function of the cerebral cortex has alpha and beta activity, respectively high during somatosensory and vestibular input in maintaining balance. In patients with balance impairments both physical and cognitive training, including neurofeedback will be helpful to improve balance abilities.

Keywords: Balance, electroencephalography activity, somatosensory, visual, vestibular.

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2436 Bridging the Green-Value-Gap: A South African Approach

Authors: E.J. Cilliers

Abstract:

Green- spaces might be very attractive, but where are the economic benefits? What value do nature and landscape have for us? What difference will it make to jobs, health and the economic strength of areas struggling with deprivation and social problems? [1].There is a need to consider green spaces from a different perspective. Green planning is not just about flora and fauna, but also about planning for economic benefits [2]. It is worth trying to quantify the value of green spaces since nature and landscape are crucially important to our quality of life and sustainable development. The reality, however, is that urban development often takes place at the expense of green spaces. Urbanization is an ongoing process throughout the world; however, hyper-urbanization without environmental planning is destructive, not constructive [3]. Urban spaces are believed to be more valuable than other land uses, particular green areas, simply because of the market value connected to urban spaces. However, attractive landscapes can help raise the quality and value of the urban market even more. In order to reach these objectives of integrated planning, the Green-Value-Gap needs to be bridged. Economists have to understand the concept of Green-Planning and the spinoffs, and Environmentalists have to understand the importance of urban economic development and the benefits thereof to green planning. An interface between Environmental Management, Economic Development and sustainable Spatial Planning are needed to bridge the Green-Value-Gap.

Keywords: Spatial Planning, Environmental Management, Green-Value-Gap, Compensation, Participation.

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2435 Enhanced Economic Evaluation – Approach for a Holistic Evaluation of Factory Planning Variants

Authors: Candy P. Schulze, Michael Brieke, Prof. Peter Nyhuis

Abstract:

The building of a factory can be a strategic investment owing to its long service life. An evaluation that only focuses, for example, on payments for the building, the technical equipment of the factory, and the personnel for the enterprise is – considering the complexity of the system factory – not sufficient for this long-term view. The success of an investment is secured, among other things, by the attainment of nonmonetary goals, too, like transformability. Such aspects are not considered in traditional investment calculations like the net present value method. This paper closes this gap with the enhanced economic evaluation (EWR) for factory planning. The procedure and the first results of an application in a project are presented.

Keywords: economic efficiency, holistic evaluation, factory planning

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2434 The Integration between Transportation Solutions, Economic Development and Community Development as an Approach for Sustainability – A Case Study of Curitiba, Brazil

Authors: G. M. Rehan, H. S. Mahmoud

Abstract:

Sustainability and sustainable development have been the main theme of many international conferences, such the UN Rio de Janeiro 1992 Earth Summit This was followed by the appearance of the global conferences at the late of the nineties and the early of 2000 to confirm the importance of the sustainable development .it was focused on the importance of the economic development as it is considered an effective tool in the operations of the sustainable development. Industry plays a critical role in technological innovations and research and development activities, which are crucial for the economic and social development of any country. Transportation and mobility are an important part or urban economics and the quality of life. To analyze urban transportation and its environmental impacts, a comprehensive approach is needed. So this research aims to apply new approach for the development of the urban communities that insure the continuity and facing the deterioration. This approach aims to integrate sustainable transport solutions with economic development and community development. For that purpose we will concentrate on one of the most sustainable cities in the world (Curitiba in Brazil) which provides the world with a model in how to integrate sustainable transport considerations into business development, road infrastructure development, and local community development.

Keywords: Community development, economic development sustainable development, sustainable transport

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2433 The Oxidative Damage Marker for Sodium Formate Exposure on Lymphocytes

Authors: Malinee Pongsavee

Abstract:

Sodium formate is the chemical substance used for food additive. Catalase is the important antioxidative enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). The resultant level of oxidative stress in sodium formatetreated lymphocytes was investigated. The sodium formate concentrations of 0.05, 0.1, 0.2, 0.4 and 0.6 mg/mL were treated in human lymphocytes for 12 hours. After 12 treated hours, catalase activity change was measured in sodium formate-treated lymphocytes. The results showed that the sodium formate concentrations of 0.4 and 0.6 mg/mL significantly decreased catalase activities in lymphocytes (P < 0.05). The change of catalase activity in sodium formate-treated lymphocytes may be the oxidative damage marker for detect sodium formate exposure in human.

Keywords: Sodium formate, catalase activity, oxidative damage marker, toxicity.

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2432 Critical Terrain Slope Calculation for Locating Small Hydropower Plants

Authors: C. Vrekos, C. Evagelides, N. Samarinas, G. Arampatzis

Abstract:

As known, the water energy is a renewable and clean source of energy. Energy production from hydropower has been the first, and still is today a renewable source used to generate electricity. The optimal location and sizing of a small hydropower plant is a very important issue in engineering design which encourages investigation. The aim of this paper is to present a formula that can be utilized for locating the position of a small hydropower plant although there is a high dependence on economic, environmental, and social parameters. In this paper, the economic and technical side of the problem is considered. More specifically, there is a critical terrain slope that determines if the plant should be located at the end of the slope or not. Of course, this formula can be used for a first estimate and does not include detailed economic analysis. At the end, a case study is presented for the location of a small hydropower plant in order to demonstrate the validity of the proposed formula.

Keywords: Critical terrain slope, economic analysis, hydropower plant locating, renewable energy.

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2431 Antibacterial Capacity of Plumeria alba Petals

Authors: M. H. Syakira, L. Brenda

Abstract:

Antibacterial activity of Plumeria alba (Frangipani) petals methanolic extracts were evaluated against Escherichia coli, Proteus vulgaris,Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus saprophyticus, Enterococcus faecalis and Serratia marcescens by using disk diffusion method. Concentration extracts (80 %) showed the highest inhibition zone towards Escherichia coli (14.3 mm). Frangipani extract also showed high antibacterial activity against Staphylococcus saprophyticus, Proteus vulgaris and Serratia marcescens, but not more than the zones of the positive control used. Comparison between two broad specrum antibiotics to frangipani extracts showed that the 80 % concentration extracts produce the same zone of inhibition as Streptomycin. Frangipani extracts showed no bacterial activity towards Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococcus faecalis. There are differences in the sensitivity of different bacteria to frangipani extracts, suggesting that frangipani-s potency varies between these bacteria. The present results indicate that frangipani showed significant antibacterial activity especially to Escherichia coli.

Keywords: Frangipani, Plumeria alba, anti microbial, Escherichia coli

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2430 Inhibitory Effects of Extracts and Isolates from Kigelia africana Fruits against Pathogenic Bacteria and Yeasts

Authors: Deepak K. Semwal, Ruchi B. Semwal, Aijaz Ahmad, Guy P. Kamatou, Alvaro M. Viljoen

Abstract:

Kigelia africana (Lam.) Benth. (Bignoniaceae) is a reputed traditional remedy for various human ailments such as skin diseases, microbial infections, melanoma, stomach troubles, metabolic disorders, malaria and general pains. In spite of the fruit being widely used for purposes related to its antibacterial and antifungal properties, the chemical constituents associated with the activity have not been fully identified. To elucidate the active principles, we evaluated the antimicrobial activity of fruit extracts and purified fractions against Staphylococcus aureus, Enterococcus faecalis, Moraxella catarrhalis, Escherichia coli, Candida albicans and Candida tropicalis. Shade-dried fruits were powdered and extracted with hydroalcoholic (1:1) mixture by soaking at room temperature for 72 h. The crude extract was further fractionated by column chromatography, with successive elution using hexane, dichloromethane, ethyl acetate, acetone and methanol. The dichloromethane and ethyl acetate fractions were combined and subjected to column chromatography to furnish a wax and oil from the eluates of 20% and 40% ethyl acetate in hexane, respectively. The GC-MS and GC×GC-MS results revealed that linoleic acid, linolenic acid, palmitic acid, arachidic acid and stearic acid were the major constituents in both oil and wax. The crude hydroalcoholic extract exhibited the strongest activity with MICs of 0.125-0.5 mg/mL, followed by the ethyl acetate (MICs = 0.125-1.0 mg/mL), dichloromethane (MICs = 0.250-2.0 mg/mL), hexane (MICs = 0.25- 2.0 mg/mL), acetone (MICs = 0.5-2.0 mg/mL) and methanol (MICs = 1.0-2.0 mg/mL), whereas the wax (MICs = 2.0-4.0 mg/mL) and oil (MICs = 4.0-8.0 mg/mL) showed poor activity. The study concludes that synergistic interactions of chemical constituents could be responsible for the antimicrobial activity of K. africana fruits, which needs a more holistic approach to understand the mechanism of its antimicrobial activity.

Keywords: Kigelia Africana, traditional medicine, antimicrobial activity, Candida albicans, palmitic acid, synergistic interaction.

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2429 Arginase Enzyme Activity in Human Serum as a Marker of Cognitive Function: The Role of Inositol in Combination with Arginine Silicate

Authors: Katie Emerson, Sara Perez-Ojalvo, Jim Komorowski, Danielle Greenberg

Abstract:

The purpose of this study was to evaluate arginase activity levels in response to combinations of an inositol-stabilized arginine silicate (ASI; Nitrosigine®), L-arginine, and Inositol. Arginine acts as a vasodilator that promotes increased blood flow resulting in enhanced delivery of oxygen and nutrients to the brain and other tissues. Arginase, found in human serum, catalyzes the conversion of arginine to ornithine and urea, completing the last step in the urea cycle. Decreasing arginase levels maintains arginine and results in increased nitric oxide production. This study aimed to determine the most effective combination of ASI, L-arginine and inositol for minimizing arginase levels and therefore maximize ASI’s effect on cognition. Serum was taken from untreated healthy donors by separation from clotted factors. Arginase activity of serum in the presence or absence of test products was determined (QuantiChrom™, DARG-100, Bioassay Systems, Hayward CA). The remaining ultra-filtrated serum units were harvested and used as the source for the arginase enzyme. ASI alone or combined with varied levels of Inositol were tested as follows: ASI + inositol at 0.25 g, 0.5 g, 0.75 g, or 1.00 g. L-arginine was also tested as a positive control. All tests elicited changes in arginase activity demonstrating the efficacy of the method used. Adding L-arginine to serum from untreated subjects, with or without inositol only had a mild effect. Adding inositol at all levels reduced arginase activity. Adding 0.5 g to the standardized amount of ASI led to the lowest amount of arginase activity as compared to the 0.25 g, 0.75 g or 1.00g doses of inositol or to L-arginine alone. The outcome of this study demonstrates an interaction of the pairing of inositol with ASI on the activity of the enzyme arginase. We found that neither the maximum nor minimum amount of inositol tested in this study led to maximal arginase inhibition. Since the inhibition of arginase activity is desirable for product formulations looking to maintain arginine levels, the most effective amount of inositol was deemed preferred. Subsequent studies suggest this moderate level of inositol in combination with ASI leads to cognitive improvements including reaction time, executive function, and concentration.

Keywords: Arginine, blood flow, colorimetry, urea cycle.

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2428 Impact of Revenue Gap on Budget Deficit, Debt Burden and Economic Growth: An Evidence from Pakistan

Authors: M. W. Siddiqi, M. Ilyas

Abstract:

Availability and mobilization of revenue is the main essential with which an economy is managed and run. While planning or while making the budgets nations set revenue targets to be achieved. But later when the accounts are closed the actual collections of revenue through taxes or even the non-tax revenue collection would invariably be different as compared to the initial estimates and targets set to be achieved. This revenue-gap distorts the whole system and the economy disturbing all the major macroeconomic indicators. This study is aimed to find out short and long term impact of revenue gap on budget deficit, debt burden and economic growth on the economy of Pakistan. For this purpose the study uses autoregressive distributed lag approach to cointegration and error correction mechanism on three different models for the period 1980 to 2009. The empirical results show that revenue gap has a short and long run relationship with economic growth and budget deficit. However, revenue gap has no impact on debt burden.

Keywords: Revenue Gap, Economic Growth, Budget Deficit, Debt Burden

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2427 Evaluation of the Antifungal and Antioxidant Activities of the Leaf Extract of Aloe vera(Aloe barbadensis Miller)

Authors: Tin A. Khaing

Abstract:

Aloe vera has been used worldwide both for pharmaceutical, food, and cosmetic industries due to the plethora of biological activities of some of its metabolites. The aim of this study was to evaluate the antifungal and antioxidant activities of the leaf extract. The antifungal activity was determined by the agar-well diffusion method against plant and human fungal pathogens. The methanol and ethanol portions of the extracts studied were more bioactive than ethyl acetate portion. It was also observed that the activity was more pronounced on plant pathogen than human pathogen except Candida albicans. This is an indication that the extract has the potential to treat plant fungal infections. The Aloe extract showed the significant antioxidant activity by the DPPH radical scavenging method. Therefore, the Aloe extract provided as natural antioxidant has been used in health foods for medical and preservative purposes.

Keywords: Aloe vera, antifungal, antioxidant, DPPH

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2426 Solubility of Organics in Water and Silicon Oil: A Comparative Study

Authors: Edison Muzenda

Abstract:

The aim of this study was to compare the solubility of selected volatile organic compounds in water and silicon oil using the simple static headspace method. The experimental design allowed equilibrium achievement within 30 – 60 minutes. Infinite dilution activity coefficients and Henry-s law constants for various organics representing esters, ketones, alkanes, aromatics, cycloalkanes and amines were measured at 303K. The measurements were reproducible with a relative standard deviation and coefficient of variation of 1.3x10-3 and 1.3 respectively. The static determined activity coefficients using shaker flasks were reasonably comparable to those obtained using the gas liquid - chromatographic technique and those predicted using the group contribution methods mainly the UNIFAC. Silicon oil chemically known as polydimethysiloxane was found to be better absorbent for VOCs than water which quickly becomes saturated. For example the infinite dilution mole fraction based activity coefficients of hexane is 0.503 and 277 000 in silicon oil and water respectively. Thus silicon oil gives a superior factor of 550 696. Henry-s law constants and activity coefficients at infinite dilution play a significant role in the design of scrubbers for abatement of volatile organic compounds from contaminated air streams. This paper presents the phase equilibrium of volatile organic compounds in very dilute aqueous and polymeric solutions indicating the movement and fate of chemical in air and solvent. The successful comparison of the results obtained here and those obtained using other methods by the same authors and in literature, means that the results obtained here are reliable.

Keywords: Abatement, absorbent, activity coefficients, equilibrium, Henry's law constant.

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2425 Palladium-Catalyzed Hydrodechlorination for Water Remediation: Catalyst Deactivation and Regeneration

Authors: Dalia Angeles-Wedler, Katrin Mackenzie, Frank-Dieter Kopinke

Abstract:

Palladium-catalyzed hydrodechlorination is a promising alternative for the treatment of environmentally relevant water bodies, such as groundwater, contaminated with chlorinated organic compounds (COCs). In the aqueous phase hydrodechlorination of COCs, Pd-based catalysts were found to have a very high catalytic activity. However, the full utilization of the catalyst-s potential is impeded by the sensitivity of the catalyst to poisoning and deactivation induced by reduced sulfur compounds (e.g. sulfides). Several regenerants have been tested before to recover the performance of sulfide-fouled Pd catalyst. But these only delivered partial success with respect to re-establishment of the catalyst activity. In this study, the deactivation behaviour of Pd/Al2O3 in the presence of sulfide was investigated. Subsequent to total deactivation the catalyst was regenerated in the aqueous phase using potassium permanganate. Under neutral pH condition, oxidative regeneration with permanganate delivered a slow recovery of catalyst activity. However, changing the pH of the bulk solution to acidic resulted in the complete recovery of catalyst activity within a regeneration time of about half an hour. These findings suggest the superiority of permanganate as regenerant in re-activating Pd/Al2O3 by oxidizing Pd-bound sulfide.

Keywords: Deactivation, hydrodechlorination, Pd catalyst, regeneration.

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2424 Techno-Economic Analysis of Motor-Generator Pair System and Virtual Synchronous Generator for Providing Inertia of Power System

Authors: Zhou Yingkun, Xu Guorui, Wei Siming, Huang Yongzhang

Abstract:

With the increasing of the penetration of renewable energy in power system, the whole inertia of the power system is declining, which will endanger the frequency stability of the power system. In order to enhance the inertia, virtual synchronous generator (VSG) has been proposed. In addition, the motor-generator pair (MGP) system is proposed to enhance grid inertia. Both of them need additional equipment to provide instantaneous energy, so the economic problem should be considered. In this paper, the basic working principle of MGP system and VSG are introduced firstly. Then, the technical characteristics and economic investment of MGP/VSG are compared by calculation and simulation. The results show that the MGP system can provide same inertia with less cost than VSG.

Keywords: High renewable energy penetration, inertia of power system, virtual synchronous generator, motor-generator pair system, techno-economic analysis.

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2423 Modeling Exponential Growth Activity Using Technology: A Research with Bachelor of Business Administration Students

Authors: V. Vargas-Alejo, L. E. Montero-Moguel

Abstract:

Understanding the concept of function has been important in mathematics education for many years. In this study, the models built by a group of five business administration and accounting undergraduate students when carrying out a population growth activity are analyzed. The theoretical framework is the Models and Modeling Perspective. The results show how the students included tables, graphics, and algebraic representations in their models. Using technology was useful to interpret, describe, and predict the situation. The first model, the students built to describe the situation, was linear. After that, they modified and refined their ways of thinking; finally, they created exponential growth. Modeling the activity was useful to deep on mathematical concepts such as covariation, rate of change, and exponential function also to differentiate between linear and exponential growth.

Keywords: Covariation reasoning, exponential function, modeling, representations.

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2422 Study on Phytochemical Properties, Antibacterial Activity and Cytotoxicity of Aloe vera L.

Authors: K. Thu, Yin Y. Mon, Tin A. Khaing, Ohn M. Tun

Abstract:

The aim of the study was to investigate phytochemical properties, antimicrobial activity and cytotoxicity of Aloe vera. The phytochemical screening of the extracts of leaves of A. vera revealed the presence of bioactive compounds such as alkaloids, tannins, flavonoids phenolic compounds, and etc. with absence of cyanogenic glycosides. Three different solvents such as methanol, ethanol and Di-Methyl sulfoxide were used to screen the antimicrobial activity of A. vera leaves against four human clinical pathogens by agar well diffusion method. The maximum antibacterial activities were observed in methanol extract followed by ethanol and Di-Methyl sulfoxide. It was also found that remarkable antibacterial activities with methanolic and ethanolic extracts of A. vera compared with the standard antibiotic, tetracycline that was not active against E. coli and S. boydii and supported the view that A. vera is a potent antimicrobial agent compared with the conventional antibiotic. Moreover, the brine shrimps (Artemia salina) toxicity test exhibited LC50 value was 569.52 ppm. The resulting data indicated that the A. vera plant have less toxic effects on brine shrimp. Hence, it is signified that Aloe vera plant extract is safe to be used as an antimicrobial agent.

Keywords: Aloe vera L., antimicrobial activity, brine shrimp, cytotoxicity, phytochemical properties.

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2421 Antimicrobial Activity and Phytochemicals Screening of Jojoba (Simmondsia chinensis) Root Extracts and Latex

Authors: Ferial M. Abu-Salem, Hayam M. Ibrahim

Abstract:

Plants are rich sources of bioactive compounds. In this study the photochemical screening of hexane, ethanolic and aqueous extracts of roots and latex of jojoba (Simmondsia chinensis) plant revealed the presence of saponins, tannins, alkaloids, steroids and glycosides. Ethanolic extract was found to be richer in these metabolites than hexane, aqueous extracts and latex. The extracts and latex displayed effective antimicrobial activity against Salmonella typhimurium, Bacillus cereus, Clostridium perfringens, Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus flavus. The increase in volume of the extracts and latex caused more activity, as shown by zones of inhibition. Candida albicans growth was inhibited only by hexane extract. Jojoba latex was not effective against Candida albicans at 0.1 and 0.5 ml extracts concentration but showed 5mm zone of inhibition at (1.0 ml). Lower volume (0.1ml) of latex encouraged Aspergillus flavus growth, while at (1.00 ml) reduced its mycelial growth. Thus, jojoba root extracts and latex can be of potential natural antimicrobial agents.

Keywords: Antimicrobial activity, Jojoba (Simmondsia chinensis), latex, photochemical, root Extracts.

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2420 Application of Single Subject Experimental Designs in Adapted Physical Activity Research: A Descriptive Analysis

Authors: Jiabei Zhang, Ying Qi

Abstract:

The purpose of this study was to develop a descriptive profile of the adapted physical activity research using single subject experimental designs. All research articles using single subject experimental designs published in the journal of Adapted Physical Activity Quarterly from 1984 to 2013 were employed as the data source. Each of the articles was coded in a subcategory of seven categories: (a) the size of sample; (b) the age of participants; (c) the type of disabilities; (d) the type of data analysis; (e) the type of designs, (f) the independent variable, and (g) the dependent variable. Frequencies, percentages, and trend inspection were used to analyze the data and develop a profile. The profile developed characterizes a small portion of research articles used single subject designs, in which most researchers used a small sample size, recruited children as subjects, emphasized learning and behavior impairments, selected visual inspection with descriptive statistics, preferred a multiple baseline design, focused on effects of therapy, inclusion, and strategy, and measured desired behaviors more often, with a decreasing trend over years.

Keywords: Adapted physical activity research, single subject experimental designs.

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2419 In vivo Introduced Extracellular Ubiquitin Regulates Intracellular Processes

Authors: Rusudan Sujashvili, Ekaterine Bakuradze, Irina Modebadze, Davit Dekanoidze

Abstract:

Extracellular ubiquitin in vivo effect on regenerative liver cells and liver histoarchitectonics has been studied. Experiments were performed on mature female white rats. Partial hepatectomy was made using the modified method of Higgins and Anderson. Standard histopathological assessment of liver tissue was used. Proliferative activity of hepatocytes was analyzed by colchicine mitotic index and immunohistochemical staining on ki67. We have found that regardless of number of injections and dose of extracellular ubiquitin liver histology has not been changed, so at tissue level no effect was observed. In vivo double injection of ubiquitin significantly decreases the mitotic activity at 32 hour point after partial hepatectomy. Thus, we can conclude that in vivo injected extracellular ubiquitin inhibits proliferative activity of hepatocytes in partially hepatectomyzed rats.

Keywords: Liver, regeneration, proliferation, ubiquitin.

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2418 “Blood Family“ Activity With Respect To Comprehensive Guidance School Program

Authors: Ali Eryılmaz

Abstract:

Children and adolescents developing in the worlds of today are facing a getting array of new and old challenges. School counselling is improving rapidly in contemporary education systems around the world. It can be said that counselling system in Turkey was newly borning. In this study, “Family of the Blood" activity is improved with respect to compherensive guidance school program. The sample included 22 adolescents who were high school students. The activity was carried out in 4 sessions, each of which lasted 45 minutes. In the first session, students- personal-social needs were determined. In the second session, in order to warm up, the students were asked three questions consisting of the constructional aspect. In the third session, the counselor and the teacher shared the results of students- responses obtained in the previous session. In the fourth session, the tables formed by students were presented in the classroom. In order to evaluate the activity, three questions were asked of the teacher and counselor. According to the results, the lesson aims of curriculum and counselling aims of curriculum were attained. In the light of literature, the results were discussed and some suggestions were made. It is taken into consideration that the activitiy was beneficial in many respects, similar studies should be carried out in the near future.

Keywords: Comprehensive guidance program, education, family

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2417 The Influence of Socio-Economic Backgrounds towards Satisfaction with Student Housing Facilities

Authors: Nurul ‘Ulyani Mohd Najib, Nor’ Aini Yusof, Zulkifli Osman

Abstract:

Studies on residential satisfaction have been actively discussed under family house setting. However, limited studies have been conducted on student residential satisfaction. This study is an attempt to fill the research gap. It focuses on the influence of socioeconomic on students- satisfaction with the universities- student housing facilities. The students who stayed at the on-campus student housing were the respondents. This study employed two-stage cluster sampling method in classifying the respondents. Self-administered questionnaires were distributed face-to-face to the students. In general, it is confirmed that students- socio-economic backgrounds have influence on the students- satisfaction with their housing facilities. The main influential factors were the students- economic status, sense of sharing, and ethnicity of their roommates. Furthermore, this study could also provide a useful feedback for the universities in order to improve their student housing facilities.

Keywords: Malaysia, Socio-economic, Student housing, Student residential satisfaction

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2416 Dictating Impact of Systemic (Trans)formations on Management Re-engineering in R&D Firms

Authors: M. Aminu Sanda

Abstract:

This paper examines challenges to the implementation and internalization of benchmarked management practices by research organizations in developing economies as transformative tools towards commercialization. The purpose is to understand the contributing influence of internal organizational factors from both situational and historical perspectives towards the practice implementation constraints, and also to provide theoretical understanding on how systemic formations and transformations in the organizations’ activities influenced the level to which their desired needs are attained. The results showed that the variability in the outcomes of the organizations’ transformation processes was indicative of their (in)ability to deal with the impacts of cumulated tensions in the systemic interfaces of their organizational activity systems. It is concluded that the functionalities of the systemic interfaces influence the functionality of the organizational activity system.

Keywords: Organizational activity system, practice implementation, systemic formations, systemic transformations, management re-engineering, R&D firms.

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2415 The Effects of an Immigration Policy on the Economic Integration of Migrants and on Natives’ Attitudes: The Case of Syrian Refugees in Turkey

Authors: S. Zeynep Siretioglu Girgin, Gizem Turna Cebeci

Abstract:

Turkey’s immigration policy is a controversial issue considering its legal, economic, social, and political and human rights dimensions. Formulation of an immigration policy goes hand in hand with political processes, where natives’ attitudes play a significant role. On the other hand, as was the case in Turkey, radical changes made in immigration policy or policies lacking transparency may cause severe reactions by the host society. The underlying discussion paper aims to analyze quantitatively the effects of the existing ‘open door’ immigration policy on the economic integration of Syrian refugees in Turkey, and on the perception of the native population of refugees. For the analysis, semi-structured in-depth interviews and focus group interviews have been conducted. After the introduction, a literature review is provided, followed by theoretical background on the explanation of natives’ attitudes towards immigrants. In the next section, a qualitative analysis of natives’ attitudes towards Syrian refugees is presented with the subtopics of (i) awareness, general opinions and expectations, (ii) open-door policy and management of the migration process, (iii) perception of positive and negative impacts of immigration, (iv) economic integration, and (v) cultural similarity. Results indicate that, natives concurrently have social, economic and security concerns regarding refugees, while difficulties regarding security and economic integration of refugees stand out. Socio-economic characteristics of the respondents, such as the educational level and employment status, are not sufficient to explain the overall attitudes towards refugees, while they can be used to explain the awareness of the respondents and the priority of the concerns felt.

Keywords: Economic integration, immigration policy, integration policies, migrants, natives’ attitudes, perception, Syrian refugees, Turkey.

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2414 Molecular Dynamics and Circular Dichroism Studies on Aurein 1.2 and Retro Analog

Authors: Safyeh Soufian, Hoosein Naderi-Manesh, Abdoali Alizadeh, Mohammad Nabi Sarbolouki

Abstract:

Aurein 1.2 is a 13-residue amphipathic peptide with antibacterial and anticancer activity. Aurein1.2 and its retro analog were synthesized to study the activity of the peptides in relation to their structure. The antibacterial test result showed the retro-analog is inactive. The secondary structural analysis by CD spectra indicated that both of the peptides at TFE/Water adopt alpha-helical conformation. MD simulation was performed on aurein 1.2 and retro-analog in water and TFE in order to analyse the factors that are involved in the activity difference between retro and the native peptide. The simulation results are discussed and validated in the light of experimental data from the CD experiment. Both of the peptides showed a relatively similar pattern for their hydrophobicity, hydrophilicity, solvent accessible surfaces, and solvent accessible hydrophobic surfaces. However, they showed different in directions of dipole moment of peptides. Also, Our results further indicate that the reversion of the amino acid sequence affects flexibility .The data also showed that factors causing structural rigidity may decrease the activity. Consequently, our finding suggests that in the case of sequence-reversed peptide strategy, one has to pay attention to the role of amino acid sequence order in making flexibility and role of dipole moment direction in peptide activity. KeywordsAntimicrobial peptides, retro, molecular dynamic, circular dichroism.

Keywords: Antimicrobial peptides, retro, molecular dynamic, circular dichroism.

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