Search results for: active linear control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16233

Search results for: active linear control

4863 Studies on Affecting Factors of Wheel Slip and Odometry Error on Real-Time of Wheeled Mobile Robots: A Review

Authors: D. Vidhyaprakash, A. Elango

Abstract:

In real-time applications, wheeled mobile robots are increasingly used and operated in extreme and diverse conditions traversing challenging surfaces such as a pitted, uneven terrain, natural flat, smooth terrain, as well as wet and dry surfaces. In order to accomplish such tasks, it is critical that the motion control functions without wheel slip and odometry error during the navigation of the two-wheeled mobile robot (WMR). Wheel slip and odometry error are disrupting factors on overall WMR performance in the form of deviation from desired trajectory, navigation, travel time and budgeted energy consumption. The wheeled mobile robot’s ability to operate at peak performance on various work surfaces without wheel slippage and odometry error is directly connected to four main parameters, which are the range of payload distribution, speed, wheel diameter, and wheel width. This paper analyses the effects of those parameters on overall performance and is concerned with determining the ideal range of parameters for optimum performance.

Keywords: wheeled mobile robot, terrain, wheel slippage, odometryerror, trajectory

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4862 Testing the Impact of Formal Interpreting Training on Working Memory Capacity: Evidence from Turkish-English Student-Interpreters

Authors: Elena Antonova Unlu, Cigdem Sagin Simsek

Abstract:

The research presents two studies examining the impact of formal interpreting training (FIT) on Working Memory Capacity (WMC) of student-interpreters. In Study 1, the storage and processing capacities of the working memory (WM) of last-year student-interpreters were compared with those of last-year Foreign Language Education (FLE) students. In Study 2, the impact of FIT on the WMC of student-interpreters was examined via comparing their results on WM tasks at the beginning and the end of their FIT. In both studies, Digit Span Task (DST) and Reading Span Task (RST) were utilized for testing storage and processing capacities of WM. The results of Study 1 revealed that the last-year student-interpreters outperformed the control groups on the RST but not on the DST. The findings of Study 2 were consistent with Study 1 showing that after FIT, the student-interpreters performed better on the RST but not on the DST. Our findings can be considered as evidence supporting the view that FIT has a beneficial effect not only on the interpreting skills of student-interpreters but also on the central executive and processing capacity of their WM.

Keywords: working memory capacity, formal interpreting training, student-interpreters, cross-sectional and longitudinal data

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4861 Evaluation of Medicinal Plants, Catunaregam spinosa, Houttuynia cordata, and Rhapis excelsa from Malaysia for Antibacterial, Antifungal and Antiviral Properties

Authors: Yik Sin Chan, Bee Ling Chuah, Wei Quan Chan, Ri Jin Cheng, Yan Hang Oon, Kong Soo Khoo, Nam Weng Sit

Abstract:

Traditionally, medicinal plants have been used to treat different kinds of ailments including infectious diseases. They serve as a good source of lead compounds for the development of new and safer anti-infective agents. This study aimed to investigate the antimicrobial potential of the leaves of three medicinal plants, namely Catunaregam spinosa (Rubiaceae; Mountain pomegranate), Houttuynia cordata (Saururaceae; "fishy-smell herb") and Rhapis excelsa (Arecaceae; “broadleaf lady palm”). The leaves extracts were obtained by sequential extraction using hexane, chloroform, ethyl acetate, ethanol, methanol and water. The antibacterial and antifungal activities were assessed using a colorimetric broth microdilution method against a panel of human pathogenic bacteria (Gram-positive: Bacillus cereus and Staphylococcus aureus; Gram-negative: Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa) and fungi (yeasts: Candida albicans, Candida parapsilosis and Cryptococcus neoformans; Moulds: Aspergillus fumigatus and Trichophyton mentagrophytes) respectively; while antiviral activity was evaluated against the Chikungunya virus on monkey kidney epithelial (Vero) cells by neutral red uptake assay. All the plant extracts showed bacteriostatic activity, however, only 72% of the extracts (13/18) were found to have bactericidal activity. The lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were given by the hexane extract of C. spinosa against S. aureus with the values of 0.16 and 0.31 mg/mL respectively. All the extracts also possessed fungistatic activity. Only the hexane, chloroform and ethyl acetate extracts of H. cordata exerted inhibitory activity against A. fumigatus, giving the lowest fungal susceptibility index of 16.7%. In contrast, only 61% of the extracts (11/18) showed fungicidal activity. The ethanol extract of R. excelsa exhibited the strongest fungicidal activity against C. albicans, C. parapsilosis and T. mentagrophytes with minimum fungicidal concentration (MFC) values of 0.04–0.08 mg/mL, in addition to its methanol extract against T. mentagrophytes (MFC=0.02 mg/mL). For anti-Chikungunya virus activity, only chloroform and ethyl acetate extracts of R. excelsa showed significant antiviral activity with 50% effective concentrations (EC50) of 29.9 and 78.1 g/mL respectively. Extracts of R. excelsa warrant further investigations into their active principles responsible for antifungal and antiviral properties.

Keywords: bactericidal, Chikungunya virus, extraction, fungicidal

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4860 Shear Reinforcement of Stone Columns During Soil Liquefaction

Authors: Zeineb Ben Salem, Wissem Frikha, Mounir Bouassida

Abstract:

The aim of this paper is to assess the effectiveness of stone columns as a liquefaction countermeasure focusing on shear reinforcementbenefit. In fact, stone columns which have high shear modulus relative to the surrounding soils potentially can carry higher shear stress levels. Thus, stone columns provide shear reinforcement and decrease the Cyclic Shear Stress Ratio CSR to which the treated soils would be subjected during an earthquake. In order to quantify the level of shear stress reduction in reinforced soil, several approaches have been developed. Nevertheless, the available approaches do not take into account the improvement of the soil parameters, mainly the shear modulusdue to stone columns installation. Indeed, in situ control tests carried out before and after the installation of stone columns based upon the results of collected data derived from 24 case histories have given evidence of the improvement of the existing soil properties.In this paper, the assessment of shear reinforcement of stone columns that accounts such improvement of the soil parameters due to stone column installation is investigated. Comparative results indicate that considering the improvement effects considerably affect the assessment of shear reinforcement for liquefaction analysis of reinforced soil by stone columns.

Keywords: stone column, liquefaction, shear reinforcement, CSR, soil improvement

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4859 Phytomining for Rare Earth Elements: A Comparative Life Cycle Assessment

Authors: Mohsen Rabbani, Trista McLaughlin, Ehsan Vahidi

Abstract:

the remediation of polluted sites with heavy metals, such as rare earth elements (REEs), has been a primary concern of researchers to decontaminate the soil. Among all developed methods to address this concern, phytoremediation has been established as efficient, cost-effective, easy-to-use, and environmentally friendly way, providing a long-term solution for addressing this global concern. Furthermore, this technology has another great potential application in the metals production sector through returning metals buried in soil via metals cropping. Considering the significant metal concentration in hyper-accumulators, the utilization of bioaccumulated metals to extract metals from plant matter has been proposed as a sub-economic area called phytomining. As a recent, more advanced technology to eliminate such pollutants from the soil and produce critical metals, bioharvesting (phytomining/agromining) has been considered another compromising way to produce metals and meet the global demand for critical/target metals. The bio-ore obtained from phytomining can be safely disposed of or introduced to metal production pathways to obtain the most demanded metals, such as REEs. It is well-known that some hyperaccumulators, e.g., fern Dicranopteris linearis, can be used to absorb REE metals from the polluted soils and accumulate them in plant organs, such as leaves and stems. After soil remediation, the plant species can be harvested and introduced to the downstream steps, namely crushing/grinding, leaching, and purification processes, to extract REEs from plant matter. This novel interdisciplinary field can fill the gap between agriculture, mining, metallurgy, and the environment. Despite the advantages of agromining for the REEs production industry, key issues related to the environmental sustainability of the entire life cycle of this new concept have not been assessed yet. Hence, a comparative life cycle assessment (LCA) study was conducted to quantify the environmental footprints of REEs phytomining. The current LCA study aims to estimate and calculate environmental effects associated with phytomining by considering critical factors, such as climate change, land use, and ozone depletion. The results revealed that phytomining is an easy-to-use and environmentally sustainable approach to either eliminate REEs from polluted sites or produce REEs, offering a new source of such metals production. This LCA research provides guidelines for researchers active in developing a reliable relationship between agriculture, mining, metallurgy, and the environment to encounter soil pollution and keep the earth green and clean.

Keywords: phytoremediation, phytomining, life cycle assessment, environmental impacts, rare earth elements, hyperaccumulator

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4858 A Descriptive Study on Syrian Entrepreneurs in Turkey

Authors: Rudainah Alkhazam, Özlem Yaşar Uğurlu

Abstract:

Immigrant entrepreneurship arises from the start of entrepreneurial activity by immigrants in the country they relocate to. The future prosperity and stability of the refugee-hosting countries depends on the mutual social and economic benefits between the residents and the refugees. Syrian refugees and workers in host countries necessitate efforts to assist their residents and refugees in meeting their daily needs, contributing lawfully to local and possibly regional economies through trade, and instilling hope in their future. This study investigates the effects of Syrian refugee entrepreneurs on host communities' business sectors, focusing on Turkey. Specifically, we examine entrepreneurship in general and its role in the country's economy. Because Turkey is the most popular resettlement destination for Syrian refugees, this study will shed light on the challenges of successful migrant entrepreneurship in Turkey and their role in the business sector. The research relies on a mixed-method approach which helps identify recurring themes, favorable results, and conflicting results across methods, allowing us to draw accurate conclusions. The study will adopt a quantitative method in collecting numerical data from Syrian refugees in Turkey. The self-administered survey would be translated into Arabic to ensure that the respondents understood the questions and possible replies. The research will use survey questionnaires to gather the majority of the data. These surveys would have closed-ended questions with nominal ratio and Likert scales. The data will be analyzed using linear regression and the Statistical Package for Social Sciences (SPSS) to ascertain the role of Syrian entrepreneurs in the business sectors of Turkey. The research will use the findings to make future recommendations. Syrian entrepreneurs, among the migrant entrepreneurs, contribute to the labor market, the majority of whom are young people. This research noted the significant participation of Syrian immigrant women in the entrepreneurship sector. The previous experience of Syrians in the field of trade and running their own business plays a vital role in the success of their business in the host countries. The study shows that Syrian entrepreneurs could integrate effectively into the various Turkish business sectors and could rely on themselves, open and manage their projects, and market them in the Turkish market. Syrian entrepreneurs consider that the investment and labor laws, commercial arrangements, and facilities for obtaining financial resources in Turkey need to be more flexible and available to immigrant entrepreneurs.

Keywords: entrepreneurship, immigration, Syrian, Turkey, refugees, investors, socio-economic benefits, unemployment

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4857 Cloud Computing in Data Mining: A Technical Survey

Authors: Ghaemi Reza, Abdollahi Hamid, Dashti Elham

Abstract:

Cloud computing poses a diversity of challenges in data mining operation arising out of the dynamic structure of data distribution as against the use of typical database scenarios in conventional architecture. Due to immense number of users seeking data on daily basis, there is a serious security concerns to cloud providers as well as data providers who put their data on the cloud computing environment. Big data analytics use compute intensive data mining algorithms (Hidden markov, MapReduce parallel programming, Mahot Project, Hadoop distributed file system, K-Means and KMediod, Apriori) that require efficient high performance processors to produce timely results. Data mining algorithms to solve or optimize the model parameters. The challenges that operation has to encounter is the successful transactions to be established with the existing virtual machine environment and the databases to be kept under the control. Several factors have led to the distributed data mining from normal or centralized mining. The approach is as a SaaS which uses multi-agent systems for implementing the different tasks of system. There are still some problems of data mining based on cloud computing, including design and selection of data mining algorithms.

Keywords: cloud computing, data mining, computing models, cloud services

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4856 Effect of Family-Based DOTS Support Program on Adherence to Health Behaviors among Patients with Pulmonary Tuberculosis in Bandung, Indonesia

Authors: D. I. Yani, S. Isaramalai, C. Kritpracha

Abstract:

Adherence to health behaviors is essential to achieve successful TB treatment. This study aimed to examine the effect of a family-based DOTS support program on adherence to health behaviors in patients with pulmonary TB. Sixty TB patients and their families were selected using cluster randomization of community health centers. The subjects were assigned into a control group, who received the routine care, and an experimental group, who received both routine care and care from the family-based DOTS support program. Paired t-test and the independent t-test were applied. The total score of adherence to health behaviors in the experimental group was significantly higher after receiving care from the family-based DOTS support program than the pretest score (t = -10.34, p < .001). Suggestions were made to expand the application of this program in various contexts and to extend knowledge for nursing practices and research.

Keywords: self-care deficit nursing theory, family-based DOTS program, pulmonary tuberculosis, adherence, health behaviors

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4855 Blockchain Platform Configuration for MyData Operator in Digital and Connected Health

Authors: Minna Pikkarainen, Yueqiang Xu

Abstract:

The integration of digital technology with existing healthcare processes has been painfully slow, a huge gap exists between the fields of strictly regulated official medical care and the quickly moving field of health and wellness technology. We claim that the promises of preventive healthcare can only be fulfilled when this gap is closed – health care and self-care becomes seamless continuum “correct information, in the correct hands, at the correct time allowing individuals and professionals to make better decisions” what we call connected health approach. Currently, the issues related to security, privacy, consumer consent and data sharing are hindering the implementation of this new paradigm of healthcare. This could be solved by following MyData principles stating that: Individuals should have the right and practical means to manage their data and privacy. MyData infrastructure enables decentralized management of personal data, improves interoperability, makes it easier for companies to comply with tightening data protection regulations, and allows individuals to change service providers without proprietary data lock-ins. This paper tackles today’s unprecedented challenges of enabling and stimulating multiple healthcare data providers and stakeholders to have more active participation in the digital health ecosystem. First, the paper systematically proposes the MyData approach for healthcare and preventive health data ecosystem. In this research, the work is targeted for health and wellness ecosystems. Each ecosystem consists of key actors, such as 1) individual (citizen or professional controlling/using the services) i.e. data subject, 2) services providing personal data (e.g. startups providing data collection apps or data collection devices), 3) health and wellness services utilizing aforementioned data and 4) services authorizing the access to this data under individual’s provided explicit consent. Second, the research extends the existing four archetypes of orchestrator-driven healthcare data business models for the healthcare industry and proposes the fifth type of healthcare data model, the MyData Blockchain Platform. This new architecture is developed by the Action Design Research approach, which is a prominent research methodology in the information system domain. The key novelty of the paper is to expand the health data value chain architecture and design from centralization and pseudo-decentralization to full decentralization, enabled by blockchain, thus the MyData blockchain platform. The study not only broadens the healthcare informatics literature but also contributes to the theoretical development of digital healthcare and blockchain research domains with a systemic approach.

Keywords: blockchain, health data, platform, action design

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4854 A Sequential Approach for Random-Effects Meta-Analysis

Authors: Samson Henry Dogo, Allan Clark, Elena Kulinskaya

Abstract:

The objective in meta-analysis is to combine results from several independent studies in order to create generalization and provide evidence based for decision making. But recent studies show that the magnitude of effect size estimates reported in many areas of research finding changed with year publication and this can impair the results and conclusions of meta-analysis. A number of sequential methods have been proposed for monitoring the effect size estimates in meta-analysis. However they are based on statistical theory applicable to fixed effect model (FEM). For random-effects model (REM), the analysis incorporates the heterogeneity variance, tau-squared and its estimation create complications. In this paper proposed the use of Gombay and Serbian (2005) truncated CUSUM-type test with asymptotically valid critical values for sequential monitoring of REM. Simulation results show that the test does not control the Type I error well, and is not recommended. Further work required to derive an appropriate test in this important area of application.

Keywords: meta-analysis, random-effects model, sequential test, temporal changes in effect sizes

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4853 Multiple Winding Multiphase Motor for Electric Drive System

Authors: Zhao Tianxu, Cui Shumei

Abstract:

This paper proposes a novel multiphase motor structure. The armature winding consists of several independent multiphase windings that have different rating rotate speed and power. Compared to conventional motor, the novel motor structure has more operation mode and fault tolerance mode, which makes it adapt to high-reliability requirement situation such as electric vehicle, aircraft and ship. Performance of novel motor structure varies with winding match. In order to find optimum control strategy, motor torque character, efficiency performance and fault tolerance ability under different operation mode are analyzed in this paper, and torque distribution strategy for efficiency optimization is proposed. Simulation analyze is taken and the result shows that proposed structure has the same efficiency on heavy load and higher efficiency on light load operation points, which expands high efficiency area of motor and cruise range of vehicle. The proposed structure can improve motor highest speed.

Keywords: multiphase motor, armature winding match, torque distribution strategy, efficiency

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4852 Partially Fluorinated Electrolyte for Lithium-Ion Batteries

Authors: Gebregziabher Brhane Berhe, Bing Joe Hwange, Wei-Nien Su

Abstract:

For a high-voltage cell, severe capacity fading is usually observed when the commercially carbonate-based electrolyte is employed due to the oxidative decomposition of solvents. To mitigate this capacity fading, an advanced electrolyte of fluoroethylene carbonate, ethyl methyl carbonate (EMC), and 1,1,2,2-Tetrafluoroetyle-2,2,3,3-tetrafluoropropyl ether (TTE) (in vol. ratio of 3:2:5) is dissolved with oxidative stability. A high-voltage lithium-ion battery was designed by coupling sulfured carbon anode from polyacrylonitrile (S-C(PAN)) and LiN0.5Mn1.5 O4 (LNMO) cathode. The discharged capacity of the cell made with modified electrolyte reaches 688 mAhg-1S a rate of 2 C, while only 19 mAhg-1S for the control electrolyte. The adopted electrolyte can effectively stabilize the sulfurized carbon anode and LNMO cathode surfaces, as the X-ray photoelectron spectroscopy (XPS) results confirmed. The developed robust high-voltage lithium-ion battery enjoys wider oxidative stability, high rate capability, and good cyclic performance, which can be attributed to the partially fluorinated electrolyte formulations with balanced viscosity and conductivity.

Keywords: high voltage, LNMO, fluorinated electrolyte, lithium-ion batteries

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4851 Static Balance in the Elderly: Comparison Between Elderly Performing Physical Activity and Fine Motor Coordination Activity

Authors: Andreia Guimaraes Farnese, Mateus Fernandes Reu Urban, Leandro Procopio, Renato Zangaro, Regiane Albertini

Abstract:

Senescence changes include postural balance, inferring the risk of falls, and can lead to fractures, bedridden, and the risk of death. Physical activity, e.g., cardiovascular exercises, is notable for improving balance due to brain cell stimulations, but fine coordination exercises also elevate cell brain metabolism. This study aimed to verify whether the elderly person who performs fine motor activity has a balance similar to that of those who practice physical activity. The subjects were divided into three groups according to the activity practice: control group (CG) with seven participants for the sedentary individuals, motor coordination group (MCG) with six participants, and activity practitioner group (PAG) with eight participants. Data comparisons were from the Berg balance scale, Time up and Go test, and stabilometric analysis. Descriptive statistical and ANOVA analyses were performed for data analysis. The results reveal that including fine motor activities can improve the balance of the elderly and indirectly decrease the risk of falls.

Keywords: balance, barapodometer, coordination, elderly

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4850 Impacts Of Salinity on Co2 Turnover in Some Gefara Soils of Libya

Authors: Fathi Elyaagubi

Abstract:

Salinization is a major threat to the productivity of agricultural land. The Gefara Plain located in the northwest of Libya; comprises about 80% of the total agricultural activity. The high water requirements for the populations and agriculture are depleting the groundwater aquifer, resulting in intrusion of seawater in the first few kilometers along the coast. Due to increasing salinity in the groundwater used for irrigation, the soils of the Gefara Plain are becoming increasingly saline. This research paper investigated the sensitivity of these soils to increased salinity using Co2 evolution as an integrating measure of soil function. Soil was collected from four sites located in the Gefara Plain, Almaya, Janzur, Gargaresh and Tajura. Soil collected from Tajura had the highest background salinity, and Janzur had the highest organic matter content. All of the soils had relatively low organic matter content, ranging between 0.49-%1.25. The cumulative rate of 14CO2 of added 14C-labelled Lolium shoots (Lolium perenne L.) to soils was decreased under effects of water containing different concentrations of NaCl at 20, 50, 70, 90, 150, and 200 mM compared to the control at any time of incubation in four sites.

Keywords: soil salinity, gefara plain, organic matter, 14C-labelled lolium shoots

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4849 Evaluation of Excision Wound Healing Activity of Ethanolic Extract of Michelia Champaca ın Diabetic Wistar Rats

Authors: Smita Shenoy, Amoolya Gowda, Tara Shanbhag, Krishnananda Prabhu, Venumadhav Nelluri

Abstract:

The study was undertaken to assess the effect of ethanolic extract of Michelia champaca on excision wound healing in diabetic wistar rats. Excision wound was made in five groups of rats after inducing diabetes with streptozotocin in four groups. Paraffin was applied to wounds in nondiabetic and diabetic control and 2.5%, 5%, 10% ointment of extract to wounds in three diabetic test groups. Monitoring of wound contraction rate, the period of epithelization and histopathological examination of granulation tissue was done. There was a significant (p < 0.05) decrease in the period of epithelization and a significant increase in the wound contraction rate on day 12 and 16 in rats treated with 5% and 10% ointment as compared to diabetic rats. There was a better organization of collagen fibers in the granulation tissue of wounds treated with 10% ointment. The higher dose of ethanolic extract of Michelia champaca promoted wound healing in diabetic Wistar rats.

Keywords: Michelia champaca, excision wound, contraction, epithelization

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4848 The Power of a Vulnerable State: The Rights Revolution and the Emergence of Human Resources Management Departments

Authors: Soheila Ghanbari

Abstract:

After the Civil Rights Act of 1964 was enacted, federal policy transformed employment rights. Equal employment opportunity law, legislation for occupational safety and health, and regulations for fringe benefits were established to ensure that employees have rights to equal protection, health and safety, and the benefits guaranteed by employers. In research analyzing data from 279 organizations over time, it was discovered that legal changes prompted organizations to establish personnel, antidiscrimination, safety, and benefits departments to ensure compliance. However, as the process of institutionalization advanced, middle managers began to separate these fresh offices from policy and rationalize them solely in economic terms as a component of the new human resources management model. This common occurrence is seen in the United States, where the Constitution represents government control of business as unlawful. It could potentially clarify the extended lack of a state theory in organizational analysis and shed light on a puzzle pointed out by state theorists: the federal state is weak in terms of administration but strong in terms of norms.

Keywords: management, state, human, resources, employment

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4847 Developing Pedagogy for Argumentation and Teacher Agency: An Educational Design Study in the UK

Authors: Zeynep Guler

Abstract:

Argumentation and the production of scientific arguments are essential components that are necessary for helping students become scientifically literate through engaging them in constructing and critiquing ideas. Incorporating argumentation into science classrooms is challenging and can be a long-term process for both students and teachers. Students have difficulty in engaging tasks that require them to craft arguments, evaluate them to seek weaknesses, and revise them. Teachers also struggle with facilitating argumentation when they have underdeveloped science practices, underdeveloped pedagogical knowledge for argumentation science teaching, or underdeveloped teaching practice with argumentation (or a combination of all three). Thus, there is a need to support teachers in developing pedagogy for science teaching as argumentation, planning and implementing teaching practice for facilitating argumentation and also in becoming more agentic in this regards. Looking specifically at the experience of agency within education, it is arguable that agency is necessary for teachers’ renegotiation of professional purposes and practices in the light of changing educational practices. This study investigated how science teachers develop pedagogy for argumentation both individually and with their colleagues and also how teachers become more agentic (or not) through the active engagement of their contexts-for-action that refer to this as an ecological understanding of agency in order to positively influence or change their practice and their students' engagement with argumentation over two academic years. Through educational design study, this study conducted with three secondary science teachers (key stage 3-year 7 students aged 11-12) in the UK to find out if similar or different patterns of developing pedagogy for argumentation and of becoming more agentic emerge as they engage in planning and implementing a cycle of activities during the practice of teaching science with argumentation. Data from video and audio-recording of classroom practice and open-ended interviews with the science teachers were analysed using content analysis. The findings indicated that all the science teachers perceived strong agency in their opportunities to develop and apply pedagogical practices within the classroom. The teachers were pro-actively shaping their practices and classroom contexts in ways that were over and above the amendments to their pedagogy. They demonstrated some outcomes in developing pedagogy for argumentation and becoming more agentic in their teaching in this regards as a result of the collaboration with their colleagues and researcher; some appeared more agentic than others. The role of the collaboration between their colleagues was seen crucial for the teachers’ practice in the schools: close collaboration and support from other teachers in planning and implementing new educational innovations were seen as crucial for the development of pedagogy and becoming more agentic in practice. They needed to understand the importance of scientific argumentation but also understand how it can be planned and integrated into classroom practice. They also perceived constraint emerged from their lack of competence and knowledge in posing appropriate questions to help the students engage in argumentation, providing support for the students' construction of oral and written arguments.

Keywords: argumentation, teacher professional development, teacher agency, students' construction of argument

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4846 Effect of Different Flours on the Physical and Sensorial Characteristics of Meatballs

Authors: Elif Aykin Dincer, Ozlem Kilic, Busra F. Bilgic, Mustafa Erbas

Abstract:

Stale breads and rusk flour are used traditionally in meatballs produced in Turkey as a structure enhancer. This study researches the possibilities of using retrograded wheat flour in the meatball production and compares the physical and sensorial characteristics of these meatballs with stale bread (traditional) and rusk (commercial) used meatballs. The cooking loss of meatballs produced with using retrograded flour was similar to that of commercial meatballs. These meatballs have an advantage with respect to cooking loss compared to traditional meatballs. Doses of retrograded flour from 5% to 20% led to a significant decrease in cooking loss, from 21.95% to 6.19%, and in the diameter of meatballs, from 18.60% to 12.74%, but to an increase in the thickness of meatballs, from 28.82% to 41.39%, respectively, compared to the control (0%). The springiness of the traditional meatballs was significantly higher than that of the other meatballs. This might have been due to the bread crumbs having a naturally springy structure. Moreover, the addition of retrograded flour in the meatballs significantly (P<0.05) affected the hardness, springiness and cohesiveness of the meatballs with respect to textural properties. In conclusion, it is considered that the use of 10% retrograded flour is ideal to improve the sensorial values of meatballs and the properties of their structure.

Keywords: cooking loss, flour, hardness, meatball, sensorial characteristics

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4845 The Design of a Phase I/II Trial of Neoadjuvant RT with Interdigitated Multiple Fractions of Lattice RT for Large High-grade Soft-Tissue Sarcoma

Authors: Georges F. Hatoum, Thomas H. Temple, Silvio Garcia, Xiaodong Wu

Abstract:

Soft Tissue Sarcomas (STS) represent a diverse group of malignancies with heterogeneous clinical and pathological features. The treatment of extremity STS aims to achieve optimal local tumor control, improved survival, and preservation of limb function. The National Comprehensive Cancer Network guidelines, based on the cumulated clinical data, recommend radiation therapy (RT) in conjunction with limb-sparing surgery for large, high-grade STS measuring greater than 5 cm in size. Such treatment strategy can offer a cure for patients. However, when recurrence occurs (in nearly half of patients), the prognosis is poor, with a median survival of 12 to 15 months and with only palliative treatment options available. The spatially-fractionated-radiotherapy (SFRT), with a long history of treating bulky tumors as a non-mainstream technique, has gained new attention in recent years due to its unconventional therapeutic effects, such as bystander/abscopal effects. Combining single fraction of GRID, the original form of SFRT, with conventional RT was shown to have marginally increased the rate of pathological necrosis, which has been recognized to have a positive correlation to overall survival. In an effort to consistently increase the pathological necrosis rate over 90%, multiple fractions of Lattice RT (LRT), a newer form of 3D SFRT, interdigitated with the standard RT as neoadjuvant therapy was conducted in a preliminary clinical setting. With favorable results of over 95% of necrosis rate in a small cohort of patients, a Phase I/II clinical study was proposed to exam the safety and feasibility of this new strategy. Herein the design of the clinical study is presented. In this single-arm, two-stage phase I/II clinical trial, the primary objectives are >80% of the patients achieving >90% tumor necrosis and to evaluation the toxicity; the secondary objectives are to evaluate the local control, disease free survival and overall survival (OS), as well as the correlation between clinical response and the relevant biomarkers. The study plans to accrue patients over a span of two years. All patient will be treated with the new neoadjuvant RT regimen, in which one of every five fractions of conventional RT is replaced by a LRT fraction with vertices receiving dose ≥10Gy while keeping the tumor periphery at or close to 2 Gy per fraction. Surgical removal of the tumor is planned to occur 6 to 8 weeks following the completion of radiation therapy. The study will employ a Pocock-style early stopping boundary to ensure patient safety. The patients will be followed and monitored for a period of five years. Despite much effort, the rarity of the disease has resulted in limited novel therapeutic breakthroughs. Although a higher rate of treatment-induced tumor necrosis has been associated with improved OS, with the current techniques, only 20% of patients with large, high-grade tumors achieve a tumor necrosis rate exceeding 50%. If this new neoadjuvant strategy is proven effective, an appreciable improvement in clinical outcome without added toxicity can be anticipated. Due to the rarity of the disease, it is hoped that such study could be orchestrated in a multi-institutional setting.

Keywords: lattice RT, necrosis, SFRT, soft tissue sarcoma

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4844 Parameter Estimation for the Oral Minimal Model and Parameter Distinctions Between Obese and Non-obese Type 2 Diabetes

Authors: Manoja Rajalakshmi Aravindakshana, Devleena Ghosha, Chittaranjan Mandala, K. V. Venkateshb, Jit Sarkarc, Partha Chakrabartic, Sujay K. Maity

Abstract:

Oral Glucose Tolerance Test (OGTT) is the primary test used to diagnose type 2 diabetes mellitus (T2DM) in a clinical setting. Analysis of OGTT data using the Oral Minimal Model (OMM) along with the rate of appearance of ingested glucose (Ra) is performed to study differences in model parameters for control and T2DM groups. The differentiation of parameters of the model gives insight into the behaviour and physiology of T2DM. The model is also studied to find parameter differences among obese and non-obese T2DM subjects and the sensitive parameters were co-related to the known physiological findings. Sensitivity analysis is performed to understand changes in parameter values with model output and to support the findings, appropriate statistical tests are done. This seems to be the first preliminary application of the OMM with obesity as a distinguishing factor in understanding T2DM from estimated parameters of insulin-glucose model and relating the statistical differences in parameters to diabetes pathophysiology.

Keywords: oral minimal model, OGTT, obese and non-obese T2DM, mathematical modeling, parameter estimation

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4843 Molecular Characterization of Arginine Sensing Response in Unravelling Host-Pathogen Interactions in Leishmania

Authors: Evanka Madan, Madhu Puri, Dan Zilberstein, Rohini Muthuswami, Rentala Madhubala

Abstract:

The extensive interaction between the host and pathogen metabolic networks decidedly shapes the outcome of infection. Utilization of arginine by the host and pathogen is critical for determining the outcome of pathogenic infection. Infections with L. donovani, an intracellular parasite, will lead to an extensive competition of arginine between the host and the parasite donovani infection. One of the major amino acid (AA) sensing signaling pathways in mammalian cells are the mammalian target of rapamycin complex I (mTORC1) pathway. mTORC1, as a sensor of nutrient, controls numerous metabolic pathways. Arginine is critical for mTORC1 activation. SLC38A9 is the arginine sensor for the mTORC1, being activated during arginine sufficiency. L. donovani transport arginine via a high-affinity transporter (LdAAP3) that is rapidly up-regulated by arginine deficiency response (ADR) in intracellular amastigotes. This study, to author’s best knowledge, investigates the interaction between two arginine sensing systems that act in the same compartment, the lysosome. One is important for macrophage defense, and the other is essential for pathogen virulence. We hypothesize that the latter modulates lysosome arginine to prevent host defense response. The work presented here identifies an upstream regulatory role of LdAAP3 in regulating the expression of SLC38A9-mTORC1 pathway, and consequently, their function in L. donovani infected THP-1 cells cultured in 0.1 mM and 1.5 mM arginine. It was found that in physiological levels of arginine (0.1 mM), infecting THP-1 with Leishmania leads to increased levels of SLC38A9 and mTORC1 via an increase in the expression of RagA. However, the reversal was observed with LdAAP3 mutants, reflecting the positive regulatory role of LdAAP3 on the host SLC38A9. At the molecular level, upon infection, mTORC1 and RagA were found to be activated at the surface of phagolysosomes which was found to form a complex with phagolysosomal localized SLC38A9. To reveal the relevance of SLC38A9 under physiological levels of arginine, endogenous SLC38A9 was depleted and a substantial reduction in the expression of host mTORC1, its downstream active substrate, p-P70S6K1 and parasite LdAAP3, was observed, thereby showing that silencing SLC38A9 suppresses ADR. In brief, to author’s best knowledge, these results reveal an upstream regulatory role of LdAAP3 in manipulating SLC38A9 arginine sensing in host macrophages. Our study indicates that intra-macrophage survival of L. donovani depends on the availability and transport of extracellular arginine. An understanding of the sensing pathway of both parasite and host will open a new perspective on the molecular mechanism of host-parasite interaction and consequently, as a treatment for Leishmaniasis.

Keywords: arginine sensing, LdAAP3, L. donovani, mTORC1, SLC38A9, THP-1

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4842 Analytical Approach to Study the Uncertainties Related to the Behavior of Structures Submitted to Differential Settlement

Authors: Elio El Kahi, Michel Khouri, Olivier Deck, Pierre Rahme, Rasool Mehdizadeh

Abstract:

Recent developments in civil engineering create multiple interaction problems between the soil and the structure. One of the major problems is the impact of ground movements on buildings. Consequently, managing risks associated with these movements, requires a determination of the different influencing factors and a specific knowledge of their variability/uncertainty. The main purpose of this research is to study the behavior of structures submitted to differential settlement, in order to assess their vulnerability, taking into consideration the different sources of uncertainties. Analytical approach is applied to investigate on one hand the influence of these uncertainties that are related to the soil, and on the other hand the structure stiffness variation with the presence of openings and the movement transmitted between them as related to the origin and shape of the free-field movement. Results reveal the effect of taking these uncertainties into consideration, and specify the dominant and most significant parameters that control the ground movement associated with the Soil-Structure Interaction (SSI) phenomenon.

Keywords: analytical approach, building, damage, differential settlement, soil-structure interaction, uncertainties

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4841 A Study on Diversity of the Family Encyrtidae (Hymenoptera: Chalcidoidea) in Forest Habitat of Doon Valley, Uttarakhand, India

Authors: Rashmi Nautiyal, Sudhir Singh

Abstract:

Encyrtidae is the largest family of superfamily Chalcidoidea of parasitic Hymenoptera group. They are endoparasitoids or hyperparasitoids of other arthropods and have the greatest impact on maintaining diversity. It not only forms a major component of diversity itself but also is very important in sustaining diversity in other groups. They are used as efficient biological control agents against key insect pests world over. The present study is based on the collection of Encyrtidae (Chalcidoidea: Hymenoptera) made during a survey in Doon Valley from 2008 to 2011 in all the five seasons (Spring, Summer cum Pre-monsoon, Monsoon, Post-monsoon, Winter) for each year. The collections were made from forest habitat in different localities of the Valley using sweep net and yellow pan trap methods. A total of 1346 specimens of encyrtids were collected and identified from the forest habitat (745 with a sweep net and 601with yellow pan trap).Of these, season-wise (post monsoon, spring, summer, monsoon, and winter) represented Encyrtids were 30.46%, 19.31%, 17.16%, 16.64% and 16.41%, respectively. A total of 161 species of Encyrtids belonging to 43 genera under 2 subfamilies were recorded.

Keywords: diversity, Encyrtidae, sweep net, yellow pan

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4840 Effect of Marine Stress Starvation Conditions on Survival and Retention of the Properties of Potential Probiotic Bacillus Strains

Authors: Abdelkarim Mahdhi, Fdhila Kais, Faouzi Lamari, Zeineb Hmila, Fathi Kamoun, Maria Ángeles Esteban, Amina Bakhrouf

Abstract:

Pathogenic bacteria are considered to be responsible for several infectious diseases in aquaculture. To overcome diseases in fish culture, the use of antimicrobial drugs as strategy, have been adopted. The use of probiotic was a promising approach to avoid the risk associated to pathogenic bacteria. To find a biological control treatment against pathogens, we undertook this investigation to study the maintain of the probiotic properties of Bacillus sp., such as viability, adhesive ability to abiotic surface, antibacterial activity and pathogenicity/toxicity, under marine starvation conditions. Our data revealed that the tested strains maintained their capacity to inhibit pathogens in vivo and in vitro conditions. These strains maintain their adhesive capacity to polystyrene and do not demonstrate the pathogenic or toxic effect to the host. The obtained results give insight about the effect of starvation conditions on the physiological responses of these Bacillus strains that can be considered as a potential candidate’s probiotic.

Keywords: bacillus, probiotic, cell viability, starvation conditions

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4839 A Preliminary in vitro Investigation of the Acetylcholinesterase and α-Amylase Inhibition Potential of Pomegranate Peel Extracts

Authors: Zoi Konsoula

Abstract:

The increasing prevalence of Alzheimer’s disease (AD) and diabetes mellitus (DM) constitutes them major global health problems. Recently, the inhibition of key enzyme activity is considered a potential treatment of both diseases. Specifically, inhibition of acetylcholinesterase (AChE), the key enzyme involved in the breakdown of the neurotransmitter acetylcholine, is a promising approach for the treatment of AD, while inhibition of α-amylase retards the hydrolysis of carbohydrates and, thus, reduces hyperglycemia. Unfortunately, commercially available AChE and α-amylase inhibitors are reported to possess side effects. Consequently, there is a need to develop safe and effective treatments for both diseases. In the present study, pomegranate peel (PP) was extracted using various solvents of increasing polarity, while two extraction methods were employed, the conventional maceration and the ultrasound assisted extraction (UAE). The concentration of bioactive phytoconstituents, such as total phenolics (TPC) and total flavonoids (TFC) in the prepared extracts was evaluated by the Folin-Ciocalteu and the aluminum-flavonoid complex method, respectively. Furthermore, the anti-neurodegenerative and anti-hyperglycemic activity of all extracts was determined using AChE and α-amylase inhibitory activity assays, respectively. The inhibitory activity of the extracts against AChE and α-amylase was characterized by estimating their IC₅₀ value using a dose-response curve, while galanthamine and acarbose were used as positive controls, respectively. Finally, the kinetics of AChE and α-amylase in the presence of the most inhibitory potent extracts was determined by the Lineweaver-Burk plot. The methanolic extract prepared using the UAE contained the highest amount of phytoconstituents, followed by the respective ethanolic extract. All extracts inhibited acetylcholinesterase in a dose-dependent manner, while the increased anticholinesterase activity of the methanolic (IC₅₀ = 32 μg/mL) and ethanolic (IC₅₀ = 42 μg/mL) extract was positively correlated with their TPC content. Furthermore, the activity of the aforementioned extracts was comparable to galanthamine. Similar results were obtained in the case of α-amylase, however, all extracts showed lower inhibitory effect on the carbohydrate hydrolyzing enzyme than on AChE, since the IC₅₀ value ranged from 84 to 100 μg/mL. Also, the α-amylase inhibitory effect of the extracts was lower than acarbose. Finally, the methanolic and ethanolic extracts prepared by UAE inhibited both enzymes in a mixed (competitive/noncompetitive) manner since the Kₘ value of both enzymes increased in the presence of extracts, while the Vmax value decreased. The results of the present study indicate that PP may be a useful source of active compounds for the management of AD and DM. Moreover, taking into consideration that PP is an agro-industrial waste product, its valorization could not only result in economic efficiency but also reduce the environmental pollution.

Keywords: acetylcholinesterase, Alzheimer’s disease, α-amylase, diabetes mellitus, pomegranate

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4838 Investigation on the Performance of Biodiesel and Natural Gas-Fuelled Diesel Engines for Shipboard Application

Authors: Kelvin Datonye Bob-Manuel

Abstract:

The shipping industry has begun to seriously look at ways of reducing fossil fuel consumption so that current reserves can last longer and operate their ships in a more environmentally friendly way. The concept of Green Shipping or Sustainable Shipping with the use of alternative fuels is now becoming an important issue for ship owners, shipping lines and ship builders globally. This paper provides a critical review of the performance of biodiesel and natural gas-fuelled diesel engines for shipboard application. The emission reduction technique included the use of either neat or emulsified rapeseed methyl ester (RME) for pilot ignition and the emission of NOx, CO2 and SOx were measured at engine speed range of 500 - 1500 r/min. The NOx concentrations were compared with the regulated IMO MARPOL73/78, Annex VI, Tiers I, II, III and United States Environmental Protection Agency (US-EPA) standard. All NOx emissions met Tier I and II levels and the EPA standard for the minimum specification of category 1 engines at higher speed but none met the MARPOL Tier III limit which is for designated Emission Control Areas (ECAs). No trace of soot and SOx emission were observed.

Keywords: dual-fuel, biodiesel, natural gas, NOx, SOx, MARPOL 73/78 Annex VI. USEPA Tier 3, EURO V &VI

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4837 A Study on Vulnerability of Alahsa Governorate to Generate Urban Heat Islands

Authors: Ilham S. M. Elsayed

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The purpose of this study is to investigate Alahsa Governorate status and its vulnerability to generate urban heat islands. Alahsa Governorate is a famous oasis in the Arabic Peninsula including several oil centers. Extensive literature review was done to collect previous relative data on the urban heat island of Alahsa Governorate. Data used for the purpose of this research were collected from authorized bodies who control weather station networks over Alahsa Governorate, Eastern Province, Saudi Arabia. Although, the number of weather station networks within the region is very limited and the analysis using GIS software and its techniques is difficult and limited, the data analyzed confirm an increase in temperature for more than 2 °C from 2004 to 2014. Such increase is considerable whenever human health and comfort are the concern. The increase of temperature within one decade confirms the availability of urban heat islands. The study concludes that, Alahsa Governorate is vulnerable to create urban heat islands and more attention should be drawn to strategic planning of the governorate that is developing with a high pace and considerable increasing levels of urbanization.

Keywords: Alahsa Governorate, population density, Urban Heat Island, weather station

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4836 The Dynamic Cone Penetration Test: A Review of Its Correlations and Applications

Authors: Abdulrahman M. Hamid

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Dynamic Cone Penetration Test (DCPT) is widely used for field quality assessment of soils. Its application to predict the engineering properties of soil is globally promoted by the fact that it is difficult to obtain undisturbed soil samples, especially when loose or submerged sandy soil is encountered. Detailed discussion will be presented on the current development of DCPT correlations with resilient modulus, relative density, California Bearing Ratio (CBR), unconfined compressive strength and shear strength that have been developed for different materials in both the laboratory and field, as well as on the usage of DCPT in quality control of compaction of earth fills and performance evaluation of pavement layers. In addition, the relationship of the DCPT with other instruments such as falling weight deflectometer, nuclear gauge, soil stiffens gauge, and plate load test will be reported. Lastely, the application of DCPT in Saudi Arabia in recent years will be addressed in this manuscript.

Keywords: dynamic cone penetration test, falling weight deflectometer, nuclear gauge, soil stiffens gauge, plate load test, automated dynamic cone penetration

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4835 AAV-Mediated Human Α-Synuclein Expression in a Rat Model of Parkinson's Disease –Further Characterization of PD Phenotype, Fine Motor Functional Effects as Well as Neurochemical and Neuropathological Changes over Time

Authors: R. Pussinen, V. Jankovic, U. Herzberg, M. Cerrada-Gimenez, T. Huhtala, A. Nurmi, T. Ahtoniemi

Abstract:

Targeted over-expression of human α-synuclein using viral-vector mediated gene delivery into the substantia nigra of rats and non-human primates has been reported to lead to dopaminergic cell loss and the formation of α-synuclein aggregates reminiscent of Lewy bodies. We have previously shown how AAV-mediated expression of α-synuclein is seen in the chronic phenotype of the rats over 16 week follow-up period. In the context of these findings, we attempted to further characterize this long term PD related functional and motor deficits as well as neurochemical and neuropathological changes in AAV-mediated α-synuclein transfection model in rats during chronic follow-up period. Different titers of recombinant AAV expressing human α-synuclein (A53T) were stereotaxically injected unilaterally into substantia nigra of Wistar rats. Rats were allowed to recover for 3 weeks prior to initial baseline behavioral testing with rotational asymmetry test, stepping test and cylinder test. A similar behavioral test battery was applied again at weeks 5, 9,12 and 15. In addition to traditionally used rat PD model tests, MotoRater test system, a high speed kinematic gait performance monitoring was applied during the follow-up period. Evaluation focused on animal gait between groups. Tremor analysis was performed on weeks 9, 12 and 15. In addition to behavioral end-points, neurochemical evaluation of dopamine and its metabolites were evaluated in striatum. Furthermore, integrity of the dopamine active transport (DAT) system was evaluated by using 123I- β-CIT and SPECT/CT imaging on weeks 3, 8 and 12 after AAV- α-synuclein transfection. Histopathology was examined from end-point samples at 3 or 12 weeks after AAV- α-synuclein transfection to evaluate dopaminergic cell viability and microglial (Iba-1) activation status in substantia nigra by using stereological analysis techniques. This study focused on the characterization and validation of previously published AAV- α-synuclein transfection model in rats but with the addition of novel end-points. We present the long term phenotype of AAV- α-synuclein transfected rats with traditionally used behavioral tests but also by using novel fine motor analysis techniques and tremor analysis which provide new insight to unilateral effects of AAV α-synuclein transfection. We also present data about neurochemical and neuropathological end-points for the dopaminergic system in the model and how well they correlate with behavioral phenotype.

Keywords: adeno-associated virus, alphasynuclein, animal model, Parkinson’s disease

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4834 Phenolic Compounds, Antiradical Activity, and Antioxidant Efficacy of Satureja hortensisl - Extracts in Vegetable Oil Protection

Authors: Abolfazl Kamkar

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Vegetable oils and fats are recognized as important components of our diet. They provide essential fatty acids, which are precursors of important hormones and control many physiological factors such as blood pressure, cholesterol level, and the reproductive system.Vegetable oils with higher contents of unsaturated fatty acids, especially polyunsaturated fatty acids (PUFAs) are more susceptible to oxidation.Protective effects of Sature jahortensis(SE) extracts in stabilizing soybean oil at different concentrations (200 and 400 ppm) were tested. Results showed that plant extracts could significantly (P< 0.05) lower the peroxide value and thiobarbituric acid value of oil during storage at 60 oC. The IC50 values for methanol and ethanol extracts were 31.5 ± 0.7 and 37.00 ± 0 µg/ml, respectively. In the β- carotene/linoleic acid system, methanol and ethanol extracts exhibited 87.5 ± 1.41% and 74.0 ±2.25 % inhibition against linoleic acid oxidation. The total phenolic and flavonoid contents of methanol and ethanol extracts were (101.58 ± 0. 26m g/ g) and (96.00 ± 0.027 mg/ g), (44.91 ± 0.14 m g/ g) and (14.30 ± 0.12 mg/ g) expressed in Gallic acid and Quercetin equivalents, respectively.These findings suggest that Satureja extracts may have potential application as natural antioxidants in the edible oil and food industry.

Keywords: satureja hortensis, antioxidant activity, oxidative stability, vegetable oil, extract

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