Search results for: protein surfactant interaction
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6164

Search results for: protein surfactant interaction

2654 Experimentally Validated Analytical Model for Thermal Analysis of Multi-Stage Depressed Collector

Authors: Vishant Gahlaut, A Mercy Latha, Sanjay Kumar Ghosh

Abstract:

Multi-stage depressed collectors (MDC) are used as an efficiency enhancement technique in traveling wave tubes the high-energy electron beam, after its interaction with the RF signal, gets velocity sorted and collected at various depressed electrodes of the MDC. The ultimate goal is to identify an optimum thermal management scheme (cooling mechanism) that could extract the heat efficiently from the electrodes. Careful thermal analysis, incorporating the cooling mechanism is required to ensure that the maximum temperature does not exceed the safe limits. A simple analytical model for quick prediction of the thermal has been developed. The model has been developed for the worst-case un-modulated DC condition, where all the thermal power is dissipated in the last electrode (typically, fourth electrode in the case of the four-stage depressed collector). It considers the thermal contact resistances at various braze joints accounting for the practical non-uniformities. Analytical results obtained from the model have been validated with simulated and experimental results.

Keywords: multi-stage depressed collector, TWTs, thermal contact resistance, thermal management

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2653 Assessment of the Association between Serum Thrombospondin-1 Levels at the Time of Admission and the Severity of Neurological Deficit in Patients with Ischemic Stroke

Authors: A. Alhusban, M. Alqawasmeh, F. Alfawares

Abstract:

Introduction: Despite improvements in stroke management, it remains the leading cause of disability worldwide. It has been suggested that enhancing brain angiogenesis after stroke will improve stroke outcome. Promoting post stroke angiogenesis requires the upregulation of angiogenic factors with a simultaneous reduction of anti-angiogenic factors. Thrombospondin-1 is the main anti-angiogenic protein in the living cells. Counterintuitively, it has been shown that animals with Thrombospondin-1 knockdown will have better stroke outcome. Data about the clinical significance of Thrombspondin-1 levels at the time of admission is still lacking. The objective of this work is to assess the association between serum Thrombospondin-1 levels measured at the time of admission and baseline neurologic severity after stroke. Patients and Methods: Blood samples were collected from patients admitted to the King Abdullah University Hospital (KAUH) with ischemic stroke at the time of admission and serum Thrombopsondin-1 levels were measured using ELISA. Patients neurologic severity was evaluated using the National Institute of Health Stroke Scale (NIHSS). Results: Samples from 50 patients admitted between January 2016 and December 2016 were collected. The median age of participants was 68 years and the median NIHSS was 3. Multinomial regression identified serum Thrombospondin-1 as an independent predictor of stroke outcome (p=0.003). Baseline serum Thrombsopondin-1 was negatively associated with NIHSS at the time of admission (spearman rho correlation coefficient=0.272, p=0.032). Conclusion: Serum Thrombospondin-1 at the time of admission may be a useful marker of stroke severity that predicts more severe neurologic severity.

Keywords: thrombospondin, stroke, neuroprotection, biomarkers

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2652 Regional Advantages Analysis: An Interactive Approach of Comparative and Competitive Advantages

Authors: Abdolrasoul Ghasemi, Ali Arabmazar Yazdi, Yasaman Boroumand, Aliasghar Banouei

Abstract:

In regional studies, choosing an appropriate approach to analyze regional success or failure has always been a challenge. Hence, this study introduces an innovative approach to establish a link between regional success and failure in the past as well as the potential success of a region in the future. The former can be sought in the historical evaluation of comparative advantages, while the latter is portrayed as competitive advantage analysis with a forward-looking approach. Based on the interaction of comparative and competitive advantages, activities are classified into four groups, including activities with no advantage, hidden advantage, fragile advantage and synergistic advantage. In analyzing the comparative advantage of activities, the location quotient method is applied, and in analyzing their competitive advantage, Porter`s diamond model using the survey method is applied. According to the results, the share of no advantage, fragile advantage, hidden advantage and synergic advantage activities are respectively 10%, 42%, 16%, and 32%. Also, to achieve economic development in regional activities, our model provides various levels of priority. First, the activities with synergistic advantage should be prioritized, then the ones with hidden advantage, and finally the activities with fragile advantage.

Keywords: regional advantage, comparative advantage, competitive advantage, Porter's diamond model

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2651 An ERP Study of Chinese Pseudo-Object Structures

Authors: Changyin Zhou

Abstract:

Verb-argument relation is a very important aspect of syntax-semantics interaction in sentence processing. Previous ERP (event related potentials) studies in this field mainly concentrated on the relation between the verb and its core arguments. The present study aims to reveal the ERP pattern of Chinese pseudo-object structures (SOSs), in which a peripheral argument is promoted to occupy the position of the patient object, as compared with the patient object structures (POSs). The ERP data were collected when participants were asked to perform acceptability judgments about Chinese phrases. Our result shows that, similar to the previous studies of number-of-argument violations, Chinese SOSs show a bilaterally distributed N400 effect. But different from all the previous studies of verb-argument relations, Chinese SOSs demonstrate a sustained anterior positivity (SAP). This SAP, which is the first report related to complexity of argument structure operation, reflects the integration difficulty of the newly promoted arguments and the progressive nature of well-formedness checking in the processing of Chinese SOSs.

Keywords: Chinese pseudo-object structures, ERP, sustained anterior positivity, verb-argument relation

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2650 Antioxidant Effects of C-Phycocyanin on Oxidized Astrocyte in Brain Injury Using 2D and 3D Neural Nanofiber Tissue Model

Authors: Seung Ju Yeon, Seul Ki Min, Jun Sang Park, Yeo Seon Kwon, Hoo Cheol Lee, Hyun Jung Shim, Il-Doo Kim, Ja Kyeong Lee, Hwa Sung Shin

Abstract:

In brain injury, depleting oxidative stress is the most effective way to reduce the brain infarct size. C-phycocyanin (C-Pc) is a well-known antioxidant protein that has neuroprotective effects obtained from green microalgae. Astrocyte is glial cell that supports the nerve cell such as neuron, which account for a large portion of the brain. In brain injury, such as ischemia and reperfusion, astrocyte has an important rule that overcomes the oxidative stress and protect from brain reactive oxygen species (ROS) injury. However little is known about how C-Pc regulates the anti-oxidants effects of astrocyte. In this study, when the C-Pc was treated in oxidized astrocyte, we confirmed that inflammatory factors Interleukin-6 and Interleukin-3 were increased and antioxidants enzyme, Superoxide dismutase (SOD) and catalase was upregulated, and neurotrophic factors, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) was alleviated. Also, it was confirmed to reduce infarct size of the brain in ischemia and reperfusion because C-Pc has anti-oxidant effects in middle cerebral artery occlusion (MCAO) animal model. These results show that C-Pc can help astrocytes lead neuroprotective activities in the oxidative stressed environment of the brain. In summary, the C-PC protects astrocytes from oxidative stress and has anti-oxidative, anti-inflammatory, neurotrophic effects under ischemic situations.

Keywords: c-phycocyanin, astrocyte, reactive oxygen species, ischemia and reperfusion, neuroprotective effect

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2649 The Design of Local Wisdom Learning for Providing Creative Activities for Juveniles with Exhibit Media: Suan-Oui Youth Center

Authors: Jong Boonpracha

Abstract:

This paper studied the application of the design of local wisdom learning for providing creative activity for juveniles with exhibit media. The Suan-oui Youth Center has the objectives to design and develop exhibit media that encourage participation and learning of youths on local wisdom of Ratanakosin Island. The research was conducted in three stages: 1) to study the principle of local wisdom learning of cultural heritage at Ratanakosin Island 2) to study exhibit media that encouraged participation and creative activities of youth on local wisdom learning, and 3) to design a youth center that provide media exhibition for local wisdom learning. The research revealed the following: 34.6 percent of respondents wanted to apply local living wisdom in their career and for hobby. At least two kinds of exhibit media effectively provided creative activities for youths. A multi-purpose area, for example, with still pictures, visual symbols, and simulations would increase the level of youths’ interaction and participation.

Keywords: exhibit media, local wisdom, youth center, design

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2648 Therapeutical Role of Copper Oxide Nanoparticles (CuO NPs) for Breast Cancer Therapy

Authors: Dipranjan Laha, Parimal Karmakar

Abstract:

Metal oxide nanoparticles are well known to generate oxidative stress and deregulate normal cellular activities. Among these, transition metals copper oxide nanoparticles (CuO NPs) are more compelling than others and able to modulate different cellular responses. In this work, we have synthesized and characterized CuO NPs by various biophysical methods. These CuO NPs (~30 nm) induce autophagy in human breast cancer cell line, MCF7 in a time and dose-dependent manner. Cellular autophagy was tested by MDC staining, induction of green fluorescent protein light chain 3 (GFP-LC3B) foci by confocal microscopy, transfection of pBABE-puro mCherry-EGFP-LC3B plasmid and western blotting of autophagy marker proteins LC3B, beclin1, and ATG5. Further, inhibition of autophagy by 3-Methyladenine (3-MA) decreased LD50 doses of CuO NPs. Such cell death was associated with the induction of apoptosis as revealed by FACS analysis, cleavage of PARP, dephosphorylation of Bad and increased cleavage product of caspase3. siRNA-mediated inhibition of autophagy-related gene beclin1 also demonstrated similar results. Finally, induction of apoptosis by 3-MA in CuO NPs treated cells were observed by TEM. This study indicates that CuO NPs are a potent inducer of autophagy which may be a cellular defense against the CuO NPs mediated toxicity and inhibition of autophagy switches the cellular response into apoptosis. A combination of CuO NPs with the autophagy inhibitor is essential to induce apoptosis in breast cancer cells. Acknowledgments: The authors would like to acknowledge for financial support for this research work to the Department of Biotechnology (No. BT/PR14661/NNT/28/494/2010), Government of India.

Keywords: nanoparticle, autophagy, apoptosis, siRNA-mediated inhibition

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2647 Nonlinear Analysis of Shear Deformable Deep Beam Resting on Nonlinear Two-Parameter Random Soil

Authors: M. Seguini, D. Nedjar

Abstract:

In this paper, the nonlinear analysis of Timoshenko beam undergoing moderate large deflections and resting on nonlinear two-parameter random foundation is presented, taking into account the effects of shear deformation, beam’s properties variation and the spatial variability of soil characteristics. The finite element probabilistic analysis has been performed by using Timoshenko beam theory with the Von Kàrmàn nonlinear strain-displacement relationships combined to Vanmarcke theory and Monte Carlo simulations, which is implemented in a Matlab program. Numerical examples of the newly developed model is conducted to confirm the efficiency and accuracy of this later and the importance of accounting for the foundation second parameter (Winkler-Pasternak). Thus, the results obtained from the developed model are presented and compared with those available in the literature to examine how the consideration of the shear and spatial variability of soil’s characteristics affects the response of the system.

Keywords: nonlinear analysis, soil-structure interaction, large deflection, Timoshenko beam, Euler-Bernoulli beam, Winkler foundation, Pasternak foundation, spatial variability

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2646 Antibacterial Activity of Noble Metal Functionalized Magnetic Core-Zeolitic Shell Nanostructures

Authors: Mohsen Padervand

Abstract:

Functionalized magnetic core-zeolitic shell nanostructures were prepared by the hydrothermal and coprecipitation methods. The products were characterized by Vibrating Sample Magnetometer (VSM), X-ray powder diffraction (XRD), Fourier Transform Infrared spectra (FTIR), nitrogen adsorption-desorption isotherms (BET) and Transmission Electron Microscopy (TEM). The growth of mordenite nanoparticles on the surface of silica coated nickel ferrite nanoparticles at the presence of organic templates was well approved. The antibacterial activity of prepared samples was investigated by the inactivation of E.coli as a gram negative bacterium. A new mechanism was proposed to inactivate the bacterium over the prepared samples. Minimum Inhibitory Concentration (MIC) and reuse ability were studied too. TEM images of the destroyed microorganism after the treatment time were applied to illustrate the inactivation mechanism. The interaction of the noble metals with organic components on the surface of nanostructures studied theoretically and the results were used to interpret the experimental results.

Keywords: nickel ferrite nanoparticles, magnetic core-zeolitic shell, antibacterial activity, E. coli

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2645 Encapsulation of Probiotic Bacteria in Complex Coacervates

Authors: L. A. Bosnea, T. Moschakis, C. Biliaderis

Abstract:

Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3% w/v) and gum arabic (GA, 3% w/v) solutions mixed at different polymer ratio (1:1, 2:1 and 4:1). The effect of total biopolymer concentration on cell viability was assessed using WPI and GA solutions of 1, 3 and 6% w/v at a constant ratio of 2:1. Also, several parameters were examined for optimization of the microcapsule formation, such as inoculum concentration and the effect of ionic strength. The viability of the bacterial cells during heat treatment and under simulated gut conditions was also evaluated. Among the different WPI/GA weight ratios tested (1:1, 2:1, and 4:1), the highest survival rate was observed for the coacervate structures made with the ratio of 2:1. The protection efficiency at low pH values is influenced by both concentration and the ratio of the added biopolymers. Moreover, the inoculum concentration seems to affect the efficiency of microcapsules to entrap the bacterial cells since an optimum level was noted at less than 8 log cfu/ml. Generally, entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73%), especially in comparison with non-encapsulated (free) cells (<19%). The encapsulated lactobacilli also exhibited enhanced viability after 10–30 min of heat treatment (65oC) as well as at different NaCl concentrations (pH 4.0). Overall, the results of this study suggest that complex coacervation with WPI/GA has a potential to deliver live probiotics in low pH food systems and fermented dairy products; the complexes can dissolve at pH 7.0 (gut environment), releasing the microbial cells.

Keywords: probiotic, complex coacervation, whey, encapsulation

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2644 The Effect of Velocity Increment by Blockage Factor on Savonius Hydrokinetic Turbine Performance

Authors: Thochi Seb Rengma, Mahendra Kumar Gupta, P. M. V. Subbarao

Abstract:

Hydrokinetic turbines can be used to produce power in inaccessible villages located near rivers. The hydrokinetic turbine uses the kinetic energy of the water and maybe put it directly into the natural flow of water without dams. For off-grid power production, the Savonius-type vertical axis turbine is the easiest to design and manufacture. This proposal uses three-dimensional computational fluid dynamics (CFD) simulations to measure the considerable interaction and complexity of turbine blades. Savonius hydrokinetic turbine (SHKT) performance is affected by a blockage in the river, canals, and waterways. Putting a large object in a water channel causes water obstruction and raises local free stream velocity. The blockage correction factor or velocity increment measures the impact of velocity on the performance. SHKT performance is evaluated by comparing power coefficient (Cp) with tip-speed ratio (TSR) at various blockage ratios. The maximum Cp was obtained at a TSR of 1.1 with a blockage ratio of 45%, whereas TSR of 0.8 yielded the highest Cp without blockage. The greatest Cp of 0.29 was obtained with a 45% blockage ratio compared to a Cp max of 0.18 without a blockage.

Keywords: savonius hydrokinetic turbine, blockage ratio, vertical axis turbine, power coefficient

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2643 The Effect of Thymoquinone and Sorafenib Combination on Hepatocellular Carcinoma Cell Line

Authors: Nabila N. El-Maraghy, Amany Essa, Yousra Abdel–Mottaleb, Nada Ismail

Abstract:

The use of combination of chemotherapy and natural products to influence the cell death with low doses of chemotherapeutic agents and few side effects has recently emerged as a new method of cancer therapy. Aim: Evaluation the modulatory effect of Thymoquinone on HepG2 cells treated with Sorafenib. Methods: Hepatocellular Carcinoma HepG2 cell line was treated with Sorafenib and TQ individually and in combination. The effect of these treatments on cell viability (MTT assay), apoptosis (Expression of Caspase-3) and oxidative markers (GSH content and extent of lipid peroxidation) was determined. Results: When compared the effect of both agents alone and the combination of the IC50 of Sorafenib and the IC50 TQ, the combination resulted in reduction of cell inhibition and apoptosis and antagonize their actions on GSH content and extent of lipid peroxidation which are increased. This study showed potent anti-tumor activity of both TQ and Sorafenib separately on HepG2 but upon combination surprisingly they interacted and give antagonistic effect. Conclusion: Co-treatment resulted in antagonistic interaction between Sorafenib and Thymoquinone.

Keywords: antagonism, hepatocellular carcinoma, sorafenib, thymoquinone

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2642 In situ Modelling of Lateral-Torsional Vibration of a Rotor-Stator with Multiple Parametric Excitations

Authors: B. X. Tchomeni, A. A. Alugongo, L. M. Masu

Abstract:

This paper presents a 4-DOF nonlinear model of a cracked of Laval rotor established based on Energy Principles. The model has been used to simulate coupled torsional-lateral response of the cracked rotor stator-system with multiple parametric excitations, namely, rotor-stator-rub, a breathing transverse crack, unbalanced mass, and an axial force. Nonlinearity due to a “breathing” crack is incorporated by considering a simple hinge model which is suitable for small breathing crack. The vibration response of a cracked rotor passing through its critical speed with rotor-stator interaction is analyzed, and an attempt for crack detection and monitoring explored. Effects of unbalanced eccentricity with phase and acceleration are investigated. By solving the motion equations, steady-state vibration response is obtained in presence of several rotor faults. The presence of a crack is observable in the power spectrum despite the excitation by the axial force and rotor-stator rub impact. Presented results are consistent with existing literature and could be adopted into rotor condition monitoring strategies

Keywords: rotor, crack, rubbing, axial force, non linear

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2641 Intelligent Computing with Bayesian Regularization Artificial Neural Networks for a Nonlinear System of COVID-19 Epidemic Model for Future Generation Disease Control

Authors: Tahir Nawaz Cheema, Dumitru Baleanu, Ali Raza

Abstract:

In this research work, we design intelligent computing through Bayesian Regularization artificial neural networks (BRANNs) introduced to solve the mathematical modeling of infectious diseases (Covid-19). The dynamical transmission is due to the interaction of people and its mathematical representation based on the system's nonlinear differential equations. The generation of the dataset of the Covid-19 model is exploited by the power of the explicit Runge Kutta method for different countries of the world like India, Pakistan, Italy, and many more. The generated dataset is approximately used for training, testing, and validation processes for every frequent update in Bayesian Regularization backpropagation for numerical behavior of the dynamics of the Covid-19 model. The performance and effectiveness of designed methodology BRANNs are checked through mean squared error, error histograms, numerical solutions, absolute error, and regression analysis.

Keywords: mathematical models, beysian regularization, bayesian-regularization backpropagation networks, regression analysis, numerical computing

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2640 Effect of Miconazole Nitrate on Immunological Response and Its Preventive Efficacy in Labeo rohita Fingerlings against Oomycetes Saprolegnia parasitica

Authors: Mukta Singh, Ratan Kumar Saha, Himadri Saha, Paramveer Singh

Abstract:

The present study evaluated the effect of sub-lethal doses of antifungal drug miconazole nitrate (MCZ) on immunological responses including immune-related gene expression and its role as a prophylactic drug against S. parasitica in Labeo rohita fingerlings. Fish were fed with sub lethal doses of MCZ i.e., T1- 6.30 mg MCZ kgBW⁻¹, T2- 12.61 mg MCZ kgBW⁻¹ and T3- 25.22 mg MCZ kgBW⁻¹ and sampling was done at different time intervals for 240 h. Immunological parameters viz. lysozyme activity, oxygen radical production and plasma anti-protease activity showed significant enhancement (p < 0.05) in fish fed with T2 and T3 doses. Significant reduction in plasma protein content was observed in all the dietary groups as compared to control. Expression of immune-relevant genes like TLR-22 and β2-M showed significantly higher expression at six h and 24 h of sampling in both liver and head-kidney. However, these genes showed a down-regulation after 120 h of sampling in both the tissues. Preventive efficacy study showed that single dose of MCZ provides protection against oomycetes up to the fourth day of infection. Significantly higher mortality was observed in control diet-fed fish as compared to fish fed with MCZ medicated diet. Thus, from the study, it can be concluded that the MCZ can act as a potent antifungal agent for preventing oomycetes infection as well as to enhance the immune response.

Keywords: antifungal, immune gene, immunological, miconazole nitrate, prophylactic

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2639 WT1 Exprassion in Malignant Surface Epithelial Ovarian Tumors

Authors: Mahmoodreza Tahamtan

Abstract:

Background: Malignant surface epithelial ovarian tumors (SEOT) account for approximately 90% of primary ovarian cancer. Wilms tumor gene (WT1) product was defined as a tumor suppressor gene, but today it is considered capable of performing oncogenic functions. There seems to be differences in WT1 expression patterns among SEOT subtypes. We evaluate the immunohistochemical expression of WT1 protein among different histologic subtypes of SEOT. Materials and Methods: Immunohistochemistry for WT1 was done on 35 serous cystadenocarcinomas, 9 borderline serous tumors, 3 mucinous cystadenocarcinomas, 10 borderline mucinous tumors, 7 endometrioid ovarian carcinomas, 3 clear cell carcinomas, 1 malignant Brenner tumor, 2 metastatic adenocarcinomas, and 6 endometrial adenocarcinomas. A tumor was considered negative if < 1% of tumor cells were stained.Positive reactions were graded as follows:1+,1%-24%; 2+,25%-49%; 3+,50%-74%; 4+,75%-100%. Results: Of the 35 cases of ovarian serous cystadenocarcinoma, 30(85.7%) were diffusely positive (3+,4+),4 showed reactivity of < 50% of the tumor cells (1+,2+), and one were negative. All 9 borderline serous tumors showed immunoreactivity with WT1. All the mucinous tumors(n:13), endometrioid carcinomas (n: 7), clear cell carcinomas (n: 3), metastatic adenocarcinomas (n: 2) and primary endometrial carcinomas (n:6) were negative. The single malignant Brenner tumor showed a positive reaction for WT1(4+) Conclusion: WT1 is a good marker to distinguish primary ovarian serous carcinomas from other surface epithelial tumors (especially endometrioid subtype) and metastatic carcinomas (especially endometrial serous carcinoma), other than malignant mesothelioma. We cannot rely to the degree of expression inorder to separate high grade borderline serous tumors from low grade ones.

Keywords: WT1, ovary, epithelial tumors, malignant

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2638 Interaction of between Cd and Zn in Barley (Hordeum vulgare L.) Plant for Phytoextraction Method

Authors: S. Adiloğlu, K. Bellitürk, Y. Solmaz, A. Adiloğlu

Abstract:

The aim of this research is to remediation of the cadmium (Cd) pollution in agricultural soils by using barley (Hordeum vulgare L.) plant. For this purpose, a pot experiment was done in greenhouse conditions. Cadmium (100 mg/kg) as CdSO4.8H2O forms was applied to each pot and incubated during 30 days. Then Ethylenediamine tetraacetic acid (EDTA) chelate was applied to each pot at five doses (0, 3, 6, 8 and 10 mmol/kg) 20 days before harvesting time of the barley plants. The plants were harvested after two months planting. According to the pot experiment results, Cd and Zn amounts of barley plant increased with increasing EDTA application and Zn and Cd contents of barley 20,13 and 1,35 mg/kg for 0 mmol /kg EDTA; 58,61 and 113,24 mg/kg for 10 mmol/kg EDTA doses, respectively. On the other hand, Cd and Zn concentrations of experiment soil increased with EDTA application to the soil samples. Zinc and Cd concentrations of soil 0,31 and 0,021 mg/kg for 0 mmol /kg EDTA; 2,39 and 67,40 mg/kg for 10 mmol/kg EDTA doses, respectively. These increases were found to be statistically significant at the level of 1 %. According to the results of the pot experiment, some heavy metal especially Cd pollution of barley (Hordeum vulgare L.) plant province can be remediated by the phytoextraction method.

Keywords: Barley, Hordeum vulgare L., cadmium, zinc, phytoextraction, soil pollution

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2637 Surface Activation of Carbon Nanotubes Generating a Chemical Interaction in Epoxy Nanocomposite

Authors: Mohamed Eldessouki, Ebraheem Shady, Yasser Gowayed

Abstract:

Carbon nanotubes (CNTs) are known for having high elastic properties with high surface area that promote them as good candidates for reinforcing polymeric matrices. In composite materials, CNTs lack chemical bonding with the surrounding matrix which decreases the possibility of better stress transfer between the components. In this work, a chemical treatment for activating the surface of the multi-wall carbon nanotubes (MWCNT) was applied and the effect of this functionalization on the elastic properties of the epoxy nanocomposites was studied. Functional amino-groups were added to the surface of the CNTs and it was evaluated to be about 34% of the total weight of the CNTs. Elastic modulus was found to increase by about 40% of the neat epoxy resin at CNTs’ weight fraction of 0.5%. The elastic modulus was found to decrease after reaching a certain concentration of CNTs which was found to be 1% wt. The scanning electron microscopic pictures showed the effect of the CNTs on the crack propagation through the sample by forming stress concentrated spots at the nanocomposite samples.

Keywords: carbon nanotubes functionalization, crack propagation, elastic modulus, epoxy nanocomposites

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2636 E-teaching Barriers: A Survey from Shanghai Primary School Teachers

Authors: Liu Dan

Abstract:

It was considered either unnecessary or impossible for primary school students to implement online teaching until last year. A large number of E-learning or E-teaching researches have been focused on adult-learners, andragogy and technology, however, primary school education, it is facing many problems that need to be solved. Therefore, this research is aimed at exploring barriers and influential factors on online teaching for K-12 students from teachers’ perspectives and discussing the E-pedagogy that is suitable for primary school students and teachers. Eight hundred and ninety-six teachers from 10 primary schools in Shanghai were invited to participate in a questionnaire survey. Data were analysed by hierarchical regression, and the results stress the significant three barriers by teachers with online teaching: the existing system is deficient in emotional interaction, teachers’ attitude towards the technology is negative and the present teacher training is lack of systematic E-pedagogy guidance. The barriers discovered by this study will help the software designers (E-lab) develop tools that allow for flexible and evolving pedagogical approaches whilst providing an easy entry point for cautious newcomers, so that help the teachers free to engage in E-teaching at pedagogical and disciplinary levels, to enhance their repertoire of teaching practices.

Keywords: online teaching barriers (OTB), e-teaching, primary school, teachers, technology

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2635 The Relationship between the Environmental and Financial Performance of Australian Electricity Producers

Authors: S. Forughi, A. De Zoysa, S. Bhati

Abstract:

The present study focuses on the environmental performance of the companies in the electricity-producing sector and its relationship with their financial performance. We will review the major studies that examined the relationship between the environmental and financial performance of firms in various industries. While the classical economic debates consider the environmental friendly activities costly and harmful to a firm’s profitability, it is claimed that firms will be rewarded with higher profitability in long run through the investments in environmental friendly activities. In this context, prior studies have examined the relationship between the environmental and financial performance of firms operating in different industry sectors. Our study will employ an environmental indicator to increase the accuracy of the results and be employed as an independent variable in our developed econometric model to evaluate the impact of the financial performance of the firms on their environmental friendly activities in the context of companies operating in the Australian electricity-producing sector. As a result, we expect our methodology to contribute to the literature and the findings of the study will help us to provide recommendations and policy implications to the electricity producers.

Keywords: Australian electricity sector, efficiency measurement, environmental-financial performance interaction, environmental index

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2634 Level of IGF-I and IGFBP-3 in Gingival Crevicular Fluid and Plasma in Patients with Aggressive Periodontitis

Authors: Youjeong Hwang

Abstract:

Purpose: Insulin-like growth factor-I (IGF-I) promotes B-cell development, immunoglobulin formation, and interleukin-6 (IL-6) production, then regulate the immune response and inflammation. As IGF-I and their receptor also exist in the periodontal tissue, they may affect the immune response caused by periodontal pathogens in aggressive periodontitis (AgP) patients. The function of IGF is regulated by IGF binding proteins (IGFBPs), and IGFBP-3 is known to most abundant in plasma. The aim of the present study was to assess the concentration of IGF-I and IGFBP-3 in plasma and gingival crevicular fluid (GCF) in AgP patients and to find out their association. Methods: Nine patients with AgP (test group) and nine healthy subjects (control group) were included in this study. None of the subjects had a history of systemic disease, smoking or steroids medication. GCF samples were collected by microcapillary pipettes and plasma samples were obtained by venipuncture. Probing pocket depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) were recorded. Samples were assayed for IGF-I and IGFBP-3 levels using ELISA. Results: Mean IGF-I level in GCF was higher in the test group than control. Mean IGF-I level in plasma and IGFBP-3 level in GCF and plasma in control group were higher than that of the test group. However, there was no statistical significance (p > 0.05). The mean level of IGF-I and IGFBP-3 in GCF was lower than those in plasma. Mean IGF-I level in plasma showed a negative correlation with PD and CAL (p < 0.05) in both groups. The levels of IGF-I and IGFBP-3 in GCF seemed to be negatively correlated with BOP in the test group (p < 0.05). Conclusions: The difference in the level of IGF-I and IGFBP-3 between AgP and healthy subjects was not significant. Further studies that explain the mechanism of the protective role of IGF-I with more samples are needed.

Keywords: aggressive periodontitis, pathogenesis, insulin-like growth factor, insulin-like growth factor binding protein

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2633 Social Assistive Robots, Reframing the Human Robotics Interaction Benchmark of Social Success

Authors: Antonio Espingardeiro

Abstract:

It is likely that robots will cross the boundaries of industry into households over the next decades. With demographic challenges worldwide, the future ageing populations will require the introduction of assistive technologies capable of providing, care, human dignity and quality of life through the aging process. Robotics technology has a high potential for being used in the areas of social and healthcare by promoting a wide range of activities such as entertainment, companionship, supervision or cognitive and physical assistance. However, such close Human Robotics Interactions (HRIs) encompass a rich set of ethical scenarios that need to be addressed before Socially Assistive Robots (SARs) reach the global markets. Such interactions with robots may seem a worthy goal for many technical/financial reasons but inevitably require close attention to the ethical dimensions of such interactions. This article investigates the current HRI benchmark of social success. It revises it according to the ethical principles of beneficence, non-maleficence and justice aligned with social care ethos. An extension of such benchmark is proposed based on an empirical study of HRIs with elderly groups.

Keywords: HRI, SARs, social success, benchmark, elderly care

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2632 Community Integration: Post-Secondary Education (PSE) and Library Programming

Authors: Leah Plocharczyk, Matthew Conner

Abstract:

This paper analyzes the relatively new trend of PSE programs which seek to provide education, vocational training, and a college experience to individuals with an intellectual and developmental disability (IDD). Specifically, the paper examines the degree of interaction between PSE programs and the libraries of their college campuses. Using ThinkCollege, a clearinghouse and advocate for PSE programs, the researchers identified 293 programs throughout the country. These were all contacted with an email survey asking them about the nature of their involvement, if any, with the academic libraries on their campus. Where indicated by the responses, the libraries of PSE programs were contacted for additional information about their programming. Responses to the survey questions were tabulated and analyzed quantitatively. Written comments were analyzed for themes which were then tabulated. This paper presents the results of this study. They show obvious preferences for library programming, such as group formal instruction, individual liaisons, embedded reference, and various instructional designs. These are discussed in terms of special education principles of mainstreaming, level of restriction, training demands and cost effectiveness. The work serves as a foundation for best practices that can advance the field.

Keywords: disability studies, instructional design, universal design for learning, assessment methodology

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2631 The Effects of Social Capital and Empowering Leadership on Team Cohesion

Authors: Y. R. Lai, J. C. Jehng, T. T. Chang

Abstract:

Team is a popular job design in the management settings. Because people on a team need to work together to complete a lot of tasks, the interaction between team members strongly influences team effectiveness. The study examines the effect of social capital and empowering leadership on team cohesion. There are three facets of social capital: structural facet, relational facet, and cognitive facet. Empowering leadership includes enhancing the meaningfulness of work, fostering participation in decision making, expressing confidence in high performance, and providing autonomy from bureaucratic constraints. Data were collected from 181 team members of 47 teams in the real estate agency industry. The results show that the relational social capital, enhancing the meaningfulness of work, and providing autonomy from bureaucratic constraints are positively related to two dimensions of team cohesion: sense of belonging and feelings of moral. Additionally, expressing confidence in high performance is negatively related to sense of belonging.

Keywords: social capital, empowering leadership, team cohesion, team effectiveness

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2630 Nutritional Status of Morbidly Obese Patients Prior to Bariatric Surgery

Authors: Azadeh Mottaghi, Reyhaneh Yousefi, Saeed Safari

Abstract:

Background: Bariatric surgery is widely proposed as the most effective approach to mitigate the growing pace of morbid obesity. As bariatric surgery candidates suffer from pre-existing nutritional deficiencies, it is of great importance to assess nutritional status of candidates before surgery in order to establish appropriate nutritional interventions. Objectives: The present study assessed and represented baseline data according to the nutritional status among candidates for bariatric surgery. Methods: A cross-sectional analysis of pre-surgery data was collected on 170 morbidly obese patients undergoing bariatric surgery between October 2017 and February 2018. Dietary intake data (evaluated through 147-item food frequency questionnaire), anthropometric measures and biochemical parameters were assessed. Results: Participants included 145 females (25 males) with average age of 37.3 ± 10.2 years, BMI of 45.7 ± 6.4 kg/m² and reported to have a total of 72.3 ± 22.2 kg excess body weight. The most common nutritional deficiencies referred to iron, ferritin, transferrin, albumin, vitamin B12, and vitamin D, the prevalence of which in the study population were as followed; 6.5, 6.5, 3, 2, 17.6 and 66%, respectively. Mean energy, protein, fat, and carbohydrate intake were 3887.3 ± 1748.32 kcal/day, 121.6 ± 57.1, 144.1 ± 83.05, and 552.4 ± 240.5 gr/day, respectively. The study population consumed lower levels of iron, calcium, folic acid, and vitamin B12 compared to the Dietary Reference Intake (DRI) recommendations (2, 26, 2.5, and 13%, respectively). Conclusion: According to the poor dietary quality of bariatric surgery candidates, leading to nutritional deficiencies pre-operatively, close monitoring and tailored supplementation pre- and post-bariatric surgery are required.

Keywords: bariatric surgery, food frequency questionnaire, obesity, nutritional status

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2629 Collagen Scaffold Incorporated with Macrotyloma uniflorum Plant Extracts as a–Burn/Wound Dressing Material, in Vitro and in Vivo Evaluation

Authors: Thangavelu Muthukumar, Thotapalli Parvathaleswara Sastry

Abstract:

Collagen is the most abundantly available connective tissue protein, which is being used as a biomaterial for various biomedical applications. Presently, fish wastes are disposed improperly which is causing serious environmental pollution resulting in offensive odour. Fish scales are promising source of Type I collagen. Medicinal plants have been used since time immemorial for treatment of various ailments of skin and dermatological disorders especially cuts, wounds, and burns. Developing biomaterials from the natural sources which are having wound healing properties within the search of a common man is the need of hour, particularly in developing and third world countries. With these objectives in view we have developed a wound dressing material containing fish scale collagen (FSC) incorporated with Macrotyloma uniflorum plant extract (PE). The wound dressing composite was characterized for its physiochemical properties using conventional methods. SEM image revealed that the composite has fibrous and porous surface which helps in transportation of oxygen as well as absorbing wound fluids. The biomaterial has shown 95% biocompatibility with required mechanical strength and has exhibited antimicrobial properties. This biomaterial has been used as a wound dressing material in experimental wounds of rats. The healing pattern was evaluated by macroscopic observations, panimetric studies, biochemical, histopathological observations. The results showed faster healing pattern in the wounds treated with CSPE compared to the other composites used in this study and untreated control. These experiments clearly suggest that CSPE can be used as wound/burn dressing materials.

Keywords: collagen, wound dressing, Macrotyloma uniflorum, burn dressing

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2628 Effects of Directivity and Fling Step on Buildings Equipped with J-Hook Sandwich Composite Walls and Reinforced Concrete Shear Walls

Authors: Majid Saaly, Shahriar Tavousi Tafreshi, Mehdi Nazari Afshar

Abstract:

The structural systems with the sandwich composite wall (SCSSC) are of very popular due to their ductileness and competency to swallow more energy and power than standard reinforced concrete shear walls. The purpose of this enhanced system is in high-rise building, Nuclear power plant facilities, and bridge slabs are much more. SCSSCs showed acceptable seismic performance under experimental tests and cyclic loading from the points of view of in-plane and out-of-plane shear and flexural interaction, in-plane punching shear, and compressive behavior. The use of sandwich composite walls with J-hook connectors has a significant effect on energy dissipation and reduction of dynamic responses of mid-rise and high-rise structural models. By changing the systems of the building from SW to SCWJ, the maximum inter-story drift values of ten- and fifteen-story models are reduced by up to 25% and 35%, respectively.

Keywords: J-Hook sandwich composite walls, fling step, directivity, IDA analyses, fractile curves

Procedia PDF Downloads 131
2627 Knowledge Sharing within a Team: Exploring the Antecedents and Role of Trust

Authors: Li Yan Hei, Au Wing Tung

Abstract:

Knowledge sharing is a process in which individuals mutually exchange existing knowledge and co-create new knowledge. Previous research has confirmed that trust is positively associated with knowledge sharing. However, only few studies systematically examined the antecedents of trust and these antecedents’ impacts on knowledge sharing. In order to explore and understand the relationships between trust and knowledge sharing in depth, this study proposed a relationship maintenance-based model to examine the antecedents of trust in knowledge sharing in project teams. Three critical elements within a project team were measured, including the environment, project team partner and interaction. It was hypothesized that the trust would lead to knowledge sharing and in turn result in perceived good team performance. With a sample of 200 Hong Kong employees, the proposed model was evaluated with structural equation modeling. Expected findings are trust will contribute to knowledge sharing, resulting in better team performance. The results will also offer insights into antecedents of trust that play a heavy role in the focal relationship. The present study contributes to a more holistic understanding of relationship between trust and knowledge sharing by linking the antecedents and outcomes. The findings will raise the awareness of project managers on ways to promote knowledge sharing.

Keywords: knowledge sharing, project management, team, trust

Procedia PDF Downloads 599
2626 Reliability-Based Ductility Seismic Spectra of Structures with Tilting

Authors: Federico Valenzuela-Beltran, Sonia E. Ruiz, Alfredo Reyes-Salazar, Juan Bojorquez

Abstract:

A reliability-based methodology which uses structural demand hazard curves to consider the increment of the ductility demands of structures with tilting is proposed. The approach considers the effect of two orthogonal components of the ground motions as well as the influence of soil-structure interaction. The approach involves the calculation of ductility demand hazard curves for symmetric systems and, alternatively, for systems with different degrees of asymmetry. To get this objective, demand hazard curves corresponding to different global ductility demands of the systems are calculated. Next, Uniform Exceedance Rate Spectra (UERS) are developed for a specific mean annual rate of exceedance value. Ratios between UERS corresponding to asymmetric and to symmetric systems located in soft soil of the valley of Mexico are obtained. Results indicate that the ductility demands corresponding to tilted structures may be several times higher than those corresponding to symmetric structures, depending on several factors such as tilting angle and vibration period of structure and soil.

Keywords: asymmetric yielding, seismic performance, structural reliability, tilted structures

Procedia PDF Downloads 495
2625 Experimental and Simulation Stress Strain Comparison of Hot Single Point Incremental Forming

Authors: Amar Al-Obaidi, Verena Kräusel, Dirk Landgrebe

Abstract:

Induction assisted single point incremental forming (IASPIF) is a flexible method and can be simply utilized to form a high strength alloys. Due to the interaction between the mechanical and thermal properties during IASPIF an evaluation for the process is necessary to be performed analytically. Therefore, a numerical simulation was carried out in this paper. The numerical analysis was operated at both room and elevated temperatures then compared with experimental results. Fully coupled dynamic temperature displacement explicit analysis was used to simulated the hot single point incremental forming. The numerical analysis was indicating that during hot single point incremental forming were a combination between complicated compression, tension and shear stresses. As a result, the equivalent plastic strain was increased excessively by rising both the formed part depth and the heating temperature during forming. Whereas, the forming forces were decreased from 5 kN at room temperature to 0.95 kN at elevated temperature. The simulation shows that the maximum true strain was occurred in the stretching zone which was the same as in experiment.

Keywords: induction heating, single point incremental forming, FE modeling, advanced high strength steel

Procedia PDF Downloads 186