Search results for: functional outcome
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4819

Search results for: functional outcome

3139 Evaluation of Pretreatment and Bioactive Compounds Recovery from Chlorella vulgaris

Authors: Marina Stramarkou, Sofia Papadaki, Konstantina Kyriakopoulou, Magdalini Krokida

Abstract:

Nowadays, microalgae represent the diverse branch of microorganism that is used not only in fish farming, but also in food, cosmetics, pharmaceuticals and biofuel production as they can produce a wide range of unique functional ingredients. In the present work, a remarkable microalga Chlorella vulgaris (CV) was selected as a raw material for the recovery of multifunctional extracts. First of all, the drying of raw biomass was examined with freeze-drying showing the best behavior. Ultrasonic-assisted extraction (UAE) using different solvents was applied under the specific optimized conditions. In case of raw biomass, ethanol was the suitable solvent, whereas on dried samples water performed better. The total carotenoid, β-carotene, chlorophyll and protein content in the raw materials, extracts and extraction residues was determined using UV-Vis spectrometry. The microalgae biomass and the extracts were evaluated regarding their antiradical activity using the DPPH method.

Keywords: antioxidant activity, pigments, proteins, ultrasound assisted extraction

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3138 Multidrug Therapies For HIV: Hybrid On-Off, Hysteresis On-Off Control and Simple STI

Authors: Magno Enrique Mendoza Meza

Abstract:

This paper deals with the comparison of three control techniques: the hysteresis on-off control (HyOOC), the hybrid on-off control (HOOC) and the simple Structured Treatment Interruptions (sSTI). These techniques are applied to the mathematical model developed by Kirschner and Webb. To compare these techniques we use a cost functional that minimize the wild-type virus population and the mutant virus population, but the main objective is to minimize the systemic cost of treatment and maximize levels of healthy CD4+ T cells. HyOOC, HOOC, and sSTI are applied to the drug therapies using a reverse transcriptase and protease inhibitors; simulations show that these controls maintain the uninfected cells in a small, bounded neighborhood of a pre-specified level. The controller HyOOC and HOOC are designed by appropriate choice of virtual equilibrium points.

Keywords: virus dynamics, on-off control, hysteresis, multi-drug therapies

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3137 Medium Composition for the Laboratory Production of Enzyme Fructosyltransferase (FTase)

Authors: O. R. Raimi, A. Lateef

Abstract:

Inoculum developments of A. niger were used for inoculation of medium for submerged fermentation and solid state fermentation. The filtrate obtained were used as sources of the extra-cellular enzymes. The FTase activities and the course of pH in submerged fermentation ranged from 7.53-24.42µ/ml and 4.4-4.8 respectively. The maximum FTase activity was obtained at 48 hours fermentation. In solid state fermentation, FTase activities ranged from 2.41-27.77µ/ml. Using ripe plantain peel and kola nut pod respectively. Both substrates supported the growth of the fungus, producing profuse growth during fermentation. In the control experiment (using kolanut pod) that lack supplementation, appreciable FTase activity of 16.92µ/ml was obtained. The optimum temperature range was 600C. it was also active at broad pH range of 1-9 with optimum obtain at pH of 5.0. FTase was stable within the range of investigated pH showing more than 60% activities. FTase can be used in the production of fructooligosaccharide, a functional food.

Keywords: Aspergillus niger, solid state fermentation, kola nut pods, Fructosyltransferase (FTase)

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3136 Finite Element Analysis of Reinforced Structural Walls

Authors: Mintesinot Teshome Mengsha

Abstract:

Reinforced concrete structural walls are provided in structures to decrease horizontal displacements under seismic loads. The cyclic lateral load resistance capacity of a structural wall is controlled by two parameters, the strength and the ductility; it is better to have the shear strength somewhat greater than the compression to prevent shear failure, which is brittle, sudden and of serious consequence. Due to architectural and functional reasons, small openings are provided in this important structural part. The main objective of this study is to investigate the finite element of RC structural walls with small openings subjected to cyclic load using the finite element approach. The experimental results in terms of load capacity, failure mode, crack pattern, flexural strength, shear strength, and deformation capacity.

Keywords: ABAQUS, finite element method, small openings, reinforced concrete structural walls

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3135 A New Correlation between SPT and CPT for Various Soils

Authors: Fauzi Jarushi, Sinan Mohsin AlKaabi

Abstract:

The Standard Penetration Test (SPT) is the most common insitu test for soil investigations. On the other hand, the Cone Penetration Test (CPT) is considered one of the best investigation tools. Due to the fast and accurate results that can be obtained it complaints the SPT in many applications like field explorations, design parameters, and quality control assessments. Many soil index and engineering properties have been correlated to both of SPT and CPT. Various foundation design methods were developed based on the outcome of these tests. Therefore it is vital to correlate these tests to each other so that either one of the tests can be used in the absence of the other, especially for preliminary evaluation and design purposes. The primary purpose of this study was to investigate the relationships between the SPT and CPT for different types of soil in Florida. Data for this research were collected from number of projects sponsored by the Florida Department of Transportation (FDOT), six sites served as the subject of SPT-CPT correlations. The correlations were established between the cone resistance (qc) and the SPT blows (i.e., N) for various soils. A positive linear relationship was found between fs and N for various soils. In general, qc versus N showed higher correlation coefficients than fs versus N. qc/N ratios were developed for different soil types and compared to literature values, the results of this research revealed higher ratios than literature values.

Keywords: in situ tests, correlation, SPT, CPT

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3134 Olive Oils from Algeria: Phenolic Compounds Composition and Antibacterial Activity

Authors: Firdaousse Laincer, Rahima Laribi, Abderazak Tamendjari, Rovellini Venturini

Abstract:

Phenolic compounds present in olive oil have received much attention in recent years due to their beneficial functional and nutritional effects. Phenolic composition, antibacterial activity of phenolic extracts of olive oil varieties from Algeria were investigated. The analysis of polyphenols was performed by Folin-Ciocalteu and HPLC. As a result, many phenolic compounds were identified and quantified by using HPLC; derivatives of oleuropein and ligstroside, hydroxytyrosol, tyrosol, flavonoids, and lignans reporting unique and characteristic phenolic profile. These phenolic fractions also differentiate the total antibacterial activity. Among the bacteria tested, S. aureus and, to a lesser extent, B. subtilis showed the highest sensitivity; the MIC varied from 0.6 to 1.6 mg•mL-1 and 1.2 to 1.8 mg•mL-1, respectively. The results obtained denote that Algerian olive oils may constitute a good source of healthy compounds, phenolics compounds, in the diet, suggesting that their consumption could be useful in the prevention of diseases.

Keywords: antibacterial activity, olive oil, phenols, HPLC

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3133 Calculation of Lattice Constants and Band Gaps for Generalized Quasicrystals of InGaN Alloy: A First Principle Study

Authors: Rohin Sharma, Sumantu Chaulagain

Abstract:

This paper presents calculations of total energy of InGaN alloy carried out in a disordered quasirandom structure for a triclinic super cell. This structure replicates the disorder and composition effect in the alloy. First principle calculations within the density functional theory with the local density approximation approach is employed to accurately determine total energy of the system. Lattice constants and band gaps associated with the ground states are then estimated for different concentration ratios of the alloy. We provide precise results of quasirandom structures of the alloy and their lattice constants with the total energy and band gap energy of the system for the range of seven different composition ratios and their respective lattice parameters.

Keywords: DFT, ground state, LDA, quasicrystal, triclinic super cell

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3132 Predictive Analysis for Big Data: Extension of Classification and Regression Trees Algorithm

Authors: Ameur Abdelkader, Abed Bouarfa Hafida

Abstract:

Since its inception, predictive analysis has revolutionized the IT industry through its robustness and decision-making facilities. It involves the application of a set of data processing techniques and algorithms in order to create predictive models. Its principle is based on finding relationships between explanatory variables and the predicted variables. Past occurrences are exploited to predict and to derive the unknown outcome. With the advent of big data, many studies have suggested the use of predictive analytics in order to process and analyze big data. Nevertheless, they have been curbed by the limits of classical methods of predictive analysis in case of a large amount of data. In fact, because of their volumes, their nature (semi or unstructured) and their variety, it is impossible to analyze efficiently big data via classical methods of predictive analysis. The authors attribute this weakness to the fact that predictive analysis algorithms do not allow the parallelization and distribution of calculation. In this paper, we propose to extend the predictive analysis algorithm, Classification And Regression Trees (CART), in order to adapt it for big data analysis. The major changes of this algorithm are presented and then a version of the extended algorithm is defined in order to make it applicable for a huge quantity of data.

Keywords: predictive analysis, big data, predictive analysis algorithms, CART algorithm

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3131 Impact of Six-Minute Walk or Rest Break during Extended GamePlay on Executive Function in First Person Shooter Esport Players

Authors: Joanne DiFrancisco-Donoghue, Seth E. Jenny, Peter C. Douris, Sophia Ahmad, Kyle Yuen, Hillary Gan, Kenney Abraham, Amber Sousa

Abstract:

Background: Guidelines for the maintenance of health of esports players and the cognitive changes that accompany competitive gaming are understudied. Executive functioning is an important cognitive skill for an esports player. The relationship between executive functions and physical exercise has been well established. However, the effects of prolonged sitting regardless of physical activity level have not been established. Prolonged uninterrupted sitting reduces cerebral blood flow. Reduced cerebral blood flow is associated with lower cognitive function and fatigue. This decrease in cerebral blood flow has been shown to be offset by frequent and short walking breaks. These short breaks can be as little as 2 minutes at the 30-minute mark and 6 minutes following 60 minutes of prolonged sitting. The rationale is the increase in blood flow and the positive effects this has on metabolic responses. The primary purpose of this study was to evaluate executive function changes following 6-minute bouts of walking and complete rest mid-session, compared to no break, during prolonged gameplay in competitive first-person shooter (FPS) esports players. Methods: This study was conducted virtually due to the Covid-19 pandemic and was approved by the New York Institute of Technology IRB. Twelve competitive FPS participants signed written consent to participate in this randomized pilot study. All participants held a gold ranking or higher. Participants were asked to play for 2 hours on three separate days. Outcome measures to test executive function included the Color Stroop and the Tower of London tests which were administered online each day prior to gaming and at the completion of gaming. All participants completed the tests prior to testing for familiarization. One day of testing consisted of a 6-minute walk break after 60-75 minutes of play. The Rate of Perceived Exertion (RPE) was recorded. The participant continued to play for another 60-75 minutes and completed the tests again. Another day the participants repeated the same methods replacing the 6-minute walk with lying down and resting for 6 minutes. On the last day, the participant played continuously with no break for 2 hours and repeated the outcome tests pre and post-play. A Latin square was used to randomize the treatment order. Results: Using descriptive statistics, the largest change in mean reaction time incorrect congruent pre to post play was seen following the 6-minute walk (662.0 (609.6) ms pre to 602.8 (539.2) ms post), followed by the 6-minute rest group (681.7(618.1) ms pre to 666.3 (607.9) ms post), and with minimal change in the continuous group (594.0(534.1) ms pre to 589.6(552.9) ms post). The mean solution time was fastest in the resting condition (7774.6(6302.8)ms), followed by the walk condition (7929.4 (5992.8)ms), with the continuous condition being slowest (9337.3(7228.7)ms). the continuous group 9337.3(7228.7) ms; 7929.4 (5992.8 ) ms 774.6(6302.8) ms. Conclusion: Short walking breaks improve blood flow and reduce the risk of venous thromboembolism during prolonged sitting. This pilot study demonstrated that a low intensity 6 -minute walk break, following 60 minutes of play, may also improve executive function in FPS gamers.

Keywords: executive function, FPS, physical activity, prolonged sitting

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3130 Synthesis and Characterizations of Sulfonated Poly (Ether Ether Ketone) Speek Nanofiber Membrane

Authors: N. Hasbullah, K. A. Sekak

Abstract:

The sulfonated poly (ether ether ketone) SPEEK nanofiber membrane were successfully electrospun for Polymer Electrolyte Membrane (PEM) in Proton Exchange Membrane Fuel Cell (PEMFC) and their nanosized properties were investigated. The poly (ether ether ketone) PEEK victrex® grade 90p was sulfonated with concentrated sulfuric acid (95-98% w/w) at room temperature for 60 hours sulfonation times. The degree sulfonation of SPEEK are 70% was determined by H1 NMR and the functional groups of the SPEEK were characterize using FTIR. Then, the SPEEK nanofiber membrane were prepared via electrospinning method using DMAC as a solvent. The SPEEK sample were successfully electrospun using predetermine set up. FESEM show the electrospun fiber mat surface and confirmed the nanostructure membrane cell.

Keywords: polymer electrolyte membrane (PEM), sulfonated poly (ether ether ketone) (SPEEK), degree sulfonation, Electrospinning, Nanofibers

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3129 Lymphatic Microvessel Density as a Prognostic Factor in Endometrial Carcinoma

Authors: Noha E. Hassan

Abstract:

Little is known regarding the influence of lymphatic microvessel density (LMVD) on prognosis in endometrial cancer. Prospective study was done in tertiary education and research hospital (Shatby Alexandria university hospital) on sixty patients presented with endometrial carcinoma underwent complete surgical staging. Our aim was to assess the intratumoral and peritumoral Lymphatic microvessel density (LMVD) of endometrial carcinomas identified by immunohistochemical staining using an antibody against podoplanin and to investigate their association with classical clinicopathological factors and prognosis. The result shows that high LMVD was associated with endometroid type of tumors, lesser myometrial, adnexal, cervical and peritoneal infiltration, lower tumor grade and stage and lesser recurrent cases. There is lower lymph node involvement among cases with high intratumoral LMVD and cases of high peritumoral LMVD; that reach statistical significance only among cases of high intratumoral LMVD. No association was seen between LMVD and lymphovascular space invasion. On the other hand, low LMVD was associated with poor outcome. Finally, we can conclude that increased LMVD is associated with favorable prognosis in endometrial cancer patients.

Keywords: endometrial carcinoma, lymphatic microvessel, microvessel density, prognosis

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3128 An Overview of Georgia’s Economic Growth Since 2012: Current Status, Challenges, and Opportunities for Future Development

Authors: V. Benidze

Abstract:

After the Rose Revolution of 2003, Georgia has achieved an unparalleled socioeconomic success. However, economic growth since 2012 has been sluggish and certainly not enough to rapidly improve the county’s standard of living that still remains substantially low compared to that in developed nations. Recent poor economic performance has shown that some key challenges need to be addressed if Georgia is to achieve high future economic growth that will decrease the poverty rate and create a middle class in the country. This paper offers in detail analysis of the economic performance of Georgia since 2012 and identifies key challenges facing the country’s economy. The main challenge going forward will be transforming Georgia from a consumption-driven to a production-oriented economy. It is identified that mobilizing domestic investment through savings, attracting foreign investment in tradable sectors and expanding the country’s export base will be crucial in the facilitation of the above-mentioned structural transformation. As the outcome of the research, the paper suggests a strategy for accelerating Georgia’ future economic growth and offers recommendations based on the relevant conclusions.

Keywords: challenges, development, economic growth, economic policy, Georgia

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3127 Measurement Errors and Misclassifications in Covariates in Logistic Regression: Bayesian Adjustment of Main and Interaction Effects and the Sample Size Implications

Authors: Shahadut Hossain

Abstract:

Measurement errors in continuous covariates and/or misclassifications in categorical covariates are common in epidemiological studies. Regression analysis ignoring such mismeasurements seriously biases the estimated main and interaction effects of covariates on the outcome of interest. Thus, adjustments for such mismeasurements are necessary. In this research, we propose a Bayesian parametric framework for eliminating deleterious impacts of covariate mismeasurements in logistic regression. The proposed adjustment method is unified and thus can be applied to any generalized linear and non-linear regression models. Furthermore, adjustment for covariate mismeasurements requires validation data usually in the form of either gold standard measurements or replicates of the mismeasured covariates on a subset of the study population. Initial investigation shows that adequacy of such adjustment depends on the sizes of main and validation samples, especially when prevalences of the categorical covariates are low. Thus, we investigate the impact of main and validation sample sizes on the adjusted estimates, and provide a general guideline about these sample sizes based on simulation studies.

Keywords: measurement errors, misclassification, mismeasurement, validation sample, Bayesian adjustment

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3126 Spiking Behavior in Memristors with Shared Top Electrode Configuration

Authors: B. Manoj Kumar, C. Malavika, E. S. Kannan

Abstract:

The objective of this study is to investigate the switching behavior of two vertically aligned memristors connected by a shared top electrode, a configuration that significantly deviates from the conventional single oxide layer sandwiched between two electrodes. The device is fabricated by bridging copper electrodes with mechanically exfoliated van der Waals metal (specifically tantalum disulfide and tantalum diselenide). The device demonstrates threshold-switching behavior in its I-V characteristics. When the input voltage signal is ramped with voltages below the threshold, the output current shows spiking behavior, resembling integrated and firing actions without extra circuitry. We also investigated the self-reset behavior of the device. Using a continuous constant voltage bias, we activated the device to the firing state. After removing the bias and reapplying it shortly afterward, the current returned to its initial state. This indicates that the device can spontaneously return to its resting state. The outcome of this investigation offers a fresh perspective on memristor-based device design and an efficient method to construct hardware for neuromorphic computing systems.

Keywords: integrated and firing, memristor, spiking behavior, threshold switching

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3125 Assessment of Women Involvement in Fishing Activities: A Case Study of Epe and Ibeju Lekki LGA, Lagos

Authors: Temitope Adewale, Oladapo Raji

Abstract:

The study was designed to investigate the assessment of women's involvement in fishing. In order to give the study a direction, five research questions, as well as two hypotheses, were postulated, and a total of fifty (50) respondents each were selected from two local government areas for the study. This brings a total of one hundred (100) respondents selected from these local government areas in Lagos state. The outcome of the finding indicates that the percentage of the respondents’ age, 49% was between 31 and 35 years, 56% has a working experience of 6-10 years, 61% were married, 69% had secondary education as their educational level. However, findings show that socio-economic characteristics (x2 =15.504, df=6, p < 0.05) and income (r=0.83, p < 0.05) have a significant relationship on the fishing. It was established that the Women in Fish production/processing were faced with a lot of constraints such as high cost of inputs, inadequate electricity supply, lack of adequate capital, non-availability of the improved oven, non-availability of extension agents, inadequate fish landing, lack of transportation facilities, lack of training on financial management and loan acquisition which affected the level of output of women in Fish processing adversely.

Keywords: women, fishing, agriculture, Lagos

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3124 A New Approach for Improving Accuracy of Multi Label Stream Data

Authors: Kunal Shah, Swati Patel

Abstract:

Many real world problems involve data which can be considered as multi-label data streams. Efficient methods exist for multi-label classification in non streaming scenarios. However, learning in evolving streaming scenarios is more challenging, as the learners must be able to adapt to change using limited time and memory. Classification is used to predict class of unseen instance as accurate as possible. Multi label classification is a variant of single label classification where set of labels associated with single instance. Multi label classification is used by modern applications, such as text classification, functional genomics, image classification, music categorization etc. This paper introduces the task of multi-label classification, methods for multi-label classification and evolution measure for multi-label classification. Also, comparative analysis of multi label classification methods on the basis of theoretical study, and then on the basis of simulation was done on various data sets.

Keywords: binary relevance, concept drift, data stream mining, MLSC, multiple window with buffer

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3123 Second-Order Complex Systems: Case Studies of Autonomy and Free Will

Authors: Eric Sanchis

Abstract:

Although there does not exist a definitive consensus on a precise definition of a complex system, it is generally considered that a system is complex by nature. The presented work illustrates a different point of view: a system becomes complex only with regard to the question posed to it, i.e., with regard to the problem which has to be solved. A complex system is a couple (question, object). Because the number of questions posed to a given object can be potentially substantial, complexity does not present a uniform face. Two types of complex systems are clearly identified: first-order complex systems and second-order complex systems. First-order complex systems physically exist. They are well-known because they have been studied by the scientific community for a long time. In second-order complex systems, complexity results from the system composition and its articulation that are partially unknown. For some of these systems, there is no evidence of their existence. Vagueness is the keyword characterizing this kind of systems. Autonomy and free will, two mental productions of the human cognitive system, can be identified as second-order complex systems. A classification based on the properties structure makes it possible to discriminate complex properties from the others and to model this kind of second order complex systems. The final outcome is an implementable synthetic property that distinguishes the solid aspects of the actual property from those that are uncertain.

Keywords: autonomy, free will, synthetic property, vaporous complex systems

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3122 Application of the Experimental Planning Design to the Notched Precracked Tensile Fracture of Composite

Authors: N. Mahmoudi, B. Guedim

Abstract:

Composite materials have important assets compared to traditional materials. They bring many functional advantages: lightness, mechanical resistance and chemical, etc. In the present study we examine the effect of a circular central notch and a precrack on the tensile fracture of two woven composite materials. The tensile tests were applied to a standardized specimen, notched and a precracked (orientation of the crack 0°, 45°, and 90°). These tensile tests were elaborated according to an experimental planning design of the type 23.31 requiring 24 experiments with three repetitions. By the analysis of regression, we obtained a mathematical model describing the maximum load according to the influential parameters (hole diameter, precrack length, angle of a precrack orientation). The specimens precracked at 90° have a better behavior than those having a precrack at 45° and still better than those having of the precracks oriented at 0°. In addition the maximum load is inversely proportional to the notch size.

Keywords: polymer matrix, glasses, fracture, precracks

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3121 Development of a Novel Ankle-Foot Orthotic Using a User Centered Approach for Improved Satisfaction

Authors: Ahlad Neti, Elisa Arch, Martha Hall

Abstract:

Studies have shown that individuals who use Ankle-Foot-Orthoses (AFOs) have a high level of dissatisfaction regarding their current AFOs. Studies point to the focus on technical design with little attention given to the user perspective as a source of AFO designs that leave users dissatisfied. To design a new AFO that satisfies users and thereby improves their quality of life, the reasons for their dissatisfaction and their wants and needs for an improved AFO design must be identified. There has been little research into the user perspective on AFO use and desired improvements, so the relationship between AFO design and satisfaction in daily use must be assessed to develop appropriate metrics and constraints prior to designing a novel AFO. To assess the user perspective on AFO design, structured interviews were conducted with 7 individuals (average age of 64.29±8.81 years) who use AFOs. All interviews were transcribed and coded to identify common themes using Grounded Theory Method in NVivo 12. Qualitative analysis of these results identified sources of user dissatisfaction such as heaviness, bulk, and uncomfortable material and overall needs and wants for an AFO. Beyond the user perspective, certain objective factors must be considered in the construction of metrics and constraints to ensure that the AFO fulfills its medical purpose. These more objective metrics are rooted in a common medical device market and technical standards. Given the large body of research concerning these standards, these objective metrics and constraints were derived through a literature review. Through these two methods, a comprehensive list of metrics and constraints accounting for both the user perspective on AFO design and the AFO’s medical purpose was compiled. These metrics and constraints will establish the framework for designing a new AFO that carries out its medical purpose while also improving the user experience. The metrics can be categorized into several overarching areas for AFO improvement. Categories of user perspective related metrics include comfort, discreteness, aesthetics, ease of use, and compatibility with clothing. Categories of medical purpose related metrics include biomechanical functionality, durability, and affordability. These metrics were used to guide an iterative prototyping process. Six concepts were ideated and compared using system-level analysis. From these six concepts, two concepts – the piano wire model and the segmented model – were selected to move forward into prototyping. Evaluation of non-functional prototypes of the piano wire and segmented models determined that the piano wire model better fulfilled the metrics by offering increased stability, longer durability, fewer points for failure, and a strong enough core component to allow a sock to cover over the AFO while maintaining the overall structure. As such, the piano wire AFO has moved forward into the functional prototyping phase, and healthy subject testing is being designed and recruited to conduct design validation and verification.

Keywords: ankle-foot orthotic, assistive technology, human centered design, medical devices

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3120 Graphene-Graphene Oxide Dopping Effect on the Mechanical Properties of Polyamide Composites

Authors: Daniel Sava, Dragos Gudovan, Iulia Alexandra Gudovan, Ioana Ardelean, Maria Sonmez, Denisa Ficai, Laurentia Alexandrescu, Ecaterina Andronescu

Abstract:

Graphene and graphene oxide have been intensively studied due to the very good properties, which are intrinsic to the material or come from the easy doping of those with other functional groups. Graphene and graphene oxide have known a broad band of useful applications, in electronic devices, drug delivery systems, medical devices, sensors and opto-electronics, coating materials, sorbents of different agents for environmental applications, etc. The board range of applications does not come only from the use of graphene or graphene oxide alone, or by its prior functionalization with different moieties, but also it is a building block and an important component in many composite devices, its addition coming with new functionalities on the final composite or strengthening the ones that are already existent on the parent product. An attempt to improve the mechanical properties of polyamide elastomers by compounding with graphene oxide in the parent polymer composition was attempted. The addition of the graphene oxide contributes to the properties of the final product, improving the hardness and aging resistance. Graphene oxide has a lower hardness and textile strength, and if the amount of graphene oxide in the final product is not correctly estimated, it can lead to mechanical properties which are comparable to the starting material or even worse, the graphene oxide agglomerates becoming a tearing point in the final material if the amount added is too high (in a value greater than 3% towards the parent material measured in mass percentages). Two different types of tests were done on the obtained materials, the hardness standard test and the tensile strength standard test, and they were made on the obtained materials before and after the aging process. For the aging process, an accelerated aging was used in order to simulate the effect of natural aging over a long period of time. The accelerated aging was made in extreme heat. For all materials, FT-IR spectra were recorded using FT-IR spectroscopy. From the FT-IR spectra only the bands corresponding to the polyamide were intense, while the characteristic bands for graphene oxide were very small in comparison due to the very small amounts introduced in the final composite along with the low absorptivity of the graphene backbone and limited number of functional groups. In conclusion, some compositions showed very promising results, both in tensile strength test and in hardness tests. The best ratio of graphene to elastomer was between 0.6 and 0.8%, this addition extending the life of the product. Acknowledgements: The present work was possible due to the EU-funding grant POSCCE-A2O2.2.1-2013-1, Project No. 638/12.03.2014, code SMIS-CSNR 48652. The financial contribution received from the national project ‘New nanostructured polymeric composites for centre pivot liners, centre plate and other components for the railway industry (RONERANANOSTRUCT)’, No: 18 PTE (PN-III-P2-2.1-PTE-2016-0146) is also acknowledged.

Keywords: graphene, graphene oxide, mechanical properties, dopping effect

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3119 A Study of Key Technologies for the Realization of Smart Grid and Its Research Situation in Pakistan and Abroad

Authors: Arjmand Khaliq, Pemra Sohaib

Abstract:

In this paper smart grid technologies which converts conventional grid into smart grid has been discussed. Integration of advanced technologies including two way communication, advanced control system, sensors, smart metering system and other provide opportunity to make conventional grid a intelligent and automatic system which is named as smart grid. This paper gives the concept of smart grid and functional characteristics of smart grid technology, summed up the research progress in Pakistan and abroad and the significance of developing smart grid. Based on the analysis of the smart grid, smart grid technologies will result a reliable and energy efficient power system in the future. On the other hand smart grid technologies have been reviewed in this paper highlighting the key technologies of smart grid, and points out the problems and challenges in the realization of smart grid.

Keywords: energy, power system reliability, power system monitoring and control, sensor, smart grid, two-way communication

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3118 An Empirical Study of Factors that Impact Government E-Services Acceptance by Citizens: Case Study from UAE

Authors: Emad Bataineh, Sara Al-Mutawa

Abstract:

The primary focus of this study is to investigate and identify the perceptions of potential end users relating to factors which impact on e-services acceptance. Technology Acceptance Model (TAM) has been adopted in this study as it can be extended when technologies are introduced. This research validates the developed TAM model and evaluates the variance of the outcome variable (acceptance of e-services). Five factors were adopted as determinants of acceptance of e-services: ease of use, security, trust, web skills, and language. The study was undertaken in the General Directorate of Residency and Foreigners Affairs (GDRFA) in the UAE. A quantitative survey methodology was adopted in this study, which surveyed 466 customers who use the GDRFA e-services. The overall findings revealed that security language, web skills and support significantly affected ease of use and perceived usefulness. However, the trust doesn’t affect the ease of use. Further, ease of use significantly affects intention to use and perceived usefulness while in turn intention to use was influenced by perceived usefulness. This study offers an understanding of people’s adoption of e-government services with the help of established theories such as TAM and various factors that influence the e-government adoption with reference to UAE.

Keywords: e-government portal, e-service, usability, TAM model

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3117 Failure Mode Effect and Criticality Analysis Based Maintenance Planning through Traditional and Multi-Criteria Decision Making Approach for Aluminium Wire Rolling Mill Plant

Authors: Nilesh Pancholi, Mangal Bhatt

Abstract:

This paper highlights comparative results of traditional FMECA and multi-factor decision-making approach based on “Technique for Order Preference by Similarity to Ideal Solution (TOPSIS)” for aluminum wire rolling mill plant. The suggested study is carried out to overcome the limitations of FMECA by assigning the scores against each failure modes in crisp values to evaluate the criticalities of the failure modes without uncertainty. The primary findings of the paper are that sudden impact on the rolls seems to be most critical failure cause and high contact stresses due to rolling & sliding action of mesh to be least critical failure cause. It is suggested to modify the current control practices with proper maintenance strategy based on achieved maintainability criticality index (MCI). The outcome of the study will be helpful in deriving optimized maintenance plan to maximize the performance of continuous process industry.

Keywords: reliability, maintenance, FMECA, TOPSIS, process industry

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3116 Robust Image Design Based Steganographic System

Authors: Sadiq J. Abou-Loukh, Hanan M. Habbi

Abstract:

This paper presents a steganography to hide the transmitted information without excite suspicious and also illustrates the level of secrecy that can be increased by using cryptography techniques. The proposed system has been implemented firstly by encrypted image file one time pad key and secondly encrypted message that hidden to perform encryption followed by image embedding. Then the new image file will be created from the original image by using four triangles operation, the new image is processed by one of two image processing techniques. The proposed two processing techniques are thresholding and differential predictive coding (DPC). Afterwards, encryption or decryption keys are generated by functional key generator. The generator key is used one time only. Encrypted text will be hidden in the places that are not used for image processing and key generation system has high embedding rate (0.1875 character/pixel) for true color image (24 bit depth).

Keywords: encryption, thresholding, differential predictive coding, four triangles operation

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3115 Additive Manufacturing of Overhangs: From Temporary Supports to Self-Support

Authors: Paulo Mendonca, Nzar Faiq Naqeshbandi

Abstract:

The objective of this study is to propose an interactive design environment that outlines the underlying computational framework to reach self-supporting overhangs. The research demonstrates the digital printability of overhangs taking into consideration factors related to the geometry design, the material used, the applied support, and the printing set-up of slicing and the extruder inclination. Parametric design tools can contribute to the design phase, form-finding, and stability optimization of self-supporting structures while printing in order to hold the components in place until they are sufficiently advanced to support themselves. The challenge is to ensure the stability of the printed parts in the critical inclinations during the whole fabrication process. Facilitating the identification of parameterization will allow to predict and optimize the process. Later, in the light of the previous findings, some guidelines of simulations and physical tests are given to be conducted for estimating the structural and functional performance.

Keywords: additive manufacturing, overhangs, self-support overhangs, printability, parametric tools

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3114 An Investigation on the Relationship between Taxi Company Safety Climate and Safety Performance of Taxi Drivers in Iloilo City

Authors: Jasper C. Dioco

Abstract:

The study was done to investigate the relationship of taxi company safety climate and drivers’ safety motivation and knowledge on taxi drivers’ safety performance. Data were collected from three Taxi Companies with taxi drivers as participants (N = 84). The Hiligaynon translated version of Transportation Companies’ Climate Scale (TCCS), Safety Motivation and Knowledge Scale, Occupational Safety Motivation Questionnaire and Global Safety Climate Scale were used to study the relationships among four parameters: (a) Taxi company safety climate; (b) Safety motivation; (c) Safety knowledge; and (d) Safety performance. Correlational analyses found that there is no relation between safety climate and safety performance. A Hierarchical regression demonstrated that safety motivation predicts the most variance in safety performance. The results will greatly impact how taxi company can increase safe performance through the confirmation of the proximity of variables to organizational outcome. A strong positive safety climate, in which employees perceive safety to be a priority and that managers are committed to their safety, is likely to increase motivation to be safety. Hence, to improve outcomes, providing knowledge based training and health promotion programs within the organization must be implemented. Policy change might include overtime rules and fatigue driving awareness programs.

Keywords: safety climate, safety knowledge, safety motivation, safety performance, taxi drivers

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3113 State of Play for the World’s Largest Greenhouse Gas Emitters

Authors: Olivia Meeschaert

Abstract:

The Conference of the Parties (COP) refers to the countries that signed on to the United Nations Framework Convention on Climate Change. This annual conference provides a platform for countries to voice their major climate concerns, negotiate on a number of global issues, and come to agreements with the world’s largest emitters on how to make incremental changes that will achieve global climate goals. Historically, the outcome of COP includes major climate pledges and international agreements. COP27 will take place in Egypt at the beginning of November 2022. The 197 parties will come together to develop solutions to the dire consequences of climate change that many people around the world are already experiencing. The war in Ukraine will require a different tone from last year’s COP, particularly given that major impacts of the war are being felt throughout Europe and have had a detrimental effect on the region’s progress in achieving the benchmarks set in their climate pledges. Last year’s COP opened with many climate advocates feeling optimistic but the commitments made in Glasgow have so far remained empty promises, and the main contributors to climate change – China, the European Union, and the United States of America – have not moved fast enough.

Keywords: environment, law and policy, climate change, greenhouse gas, conference of the parties, China, United States, European Union

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3112 An Efficient Algorithm for Global Alignment of Protein-Protein Interaction Networks

Authors: Duc Dong Do, Ngoc Ha Tran, Thanh Hai Dang, Cao Cuong Dang, Xuan Huan Hoang

Abstract:

Global aligning two protein-protein interaction networks is an essentially important task in bioinformatics/computational biology field of study. It is a challenging and widely studied research topic in recent years. Accurately aligned networks allow us to identify functional modules of proteins and/ororthologous proteins from which unknown functions of a protein can be inferred. We here introduce a novel efficient heuristic global network alignment algorithm called FASTAn, including two phases: the first to construct an initial alignment and the second to improve such alignment by exerting a local optimization repeated procedure. The experimental results demonstrated that FASTAn outperformed the state-of-the-art global network alignment algorithm namely SPINAL in terms of both commonly used objective scores and the run-time.

Keywords: FASTAn, Heuristic algorithm, biological network alignment, protein-protein interaction networks

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3111 Human Dental Pulp Stem Cells Attenuate Streptozotocin-Induced Parotid Gland Injury in Rats

Authors: Gehan ElAkabawy

Abstract:

Background: Diabetes mellitus causes severe deteriorations of almost all the organs and systems of the body, as well as significant damage to the oral cavity. The oral changes are mainly related to salivary glands dysfunction characterized by hyposalivation and xerostomia, which significantly reduce diabetic patients’ quality of life. Human dental pulp stem cells represent a promising source for cell-based therapies, owing to their easy, minimally invasive surgical access, and high proliferative capacity. It was reported that the trophic support mediated by dental pulp stem cells can rescue the functional and structural alterations of damaged salivary glands. However, potential differentiation and paracrine effects of human dental pulp stem cells in diabetic-induced parotid gland damage have not been previously investigated. Our study aimed to investigate the therapeutic effects of intravenous transplantation of human dental pulp stem cells (hDPSCs) on parotid gland injury in a rat model of streptozotocin (STZ)-induced type 1 diabetes. Methods: Thirty Sprague-Dawley male rats were randomly categorised into three groups: control, diabetic (STZ), and transplanted (STZ+hDPSCs). hDPSCs or vehicle was injected into the tail vein 7 days after STZ injection. The fasting blood glucose levels were monitored weekly. A glucose tolerance test was performed, and the parotid gland weight, salivary flow rate, oxidative stress indices, parotid gland histology, and caspase-3, vascular endothelial growth factor (VEGF), and proliferating cell nuclear antigen (PCNA) expression in parotid tissues were assessed 28 days post-transplantation. Results: Transplantation of hDPSCs downregulated blood glucose, improved the salivary flow rate, and reduced oxidative stress. The cells migrated to, survived, and differentiated into acinar, ductal, and myoepithelial cells in the STZ-injured parotid gland. Moreover, they downregulated the expression of caspase-3 and upregulated the expression of VEGF and PCNA, likely exerting pro-angiogenetic and antiapoptotic effects and promoting endogenous regeneration. In addition, the transplanted cells enhanced the parotid nitric oxide (NO) -tetrahydrobiopterin (BH4) pathway. Conclusions: Our results show that hDPSCs can migrate to and survive within the STZ-injured parotid gland, where they prevent its functional and morphological damage by restoring normal glucose levels, differentiating into parotid cell populations, and stimulating paracrine-mediated regeneration. Thus, hDPSCs may have therapeutic potential in the treatment of diabetes-induced parotid gland injury.

Keywords: dental pulp stem cells, diabetes, streptozotocin, parotid gland

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3110 Switched Uses of a Bidirectional Microphone as a Microphone and Sensors with High Gain and Wide Frequency Range

Authors: Toru Shionoya, Yosuke Kurihara, Takashi Kaburagi, Kajiro Watanabe

Abstract:

Mass-produced bidirectional microphones have attractive characteristics. They work as a microphone as well as a sensor with high gain over a wide frequency range; they are also highly reliable and economical. We present novel multiple functional uses of the microphones. A mathematical model for explaining the high-pass-filtering characteristics of bidirectional microphones was presented. Based on the model, the characteristics of the microphone were investigated, and a novel use for the microphone as a sensor with a wide frequency range was presented. In this study, applications for using the microphone as a security sensor and a human biosensor were introduced. The mathematical model was validated through experiments, and the feasibility of the abovementioned applications for security monitoring and the biosignal monitoring were examined through experiments.

Keywords: bidirectional microphone, low-frequency, mathematical model, frequency response

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