Search results for: negative phase
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8796

Search results for: negative phase

4326 A Full-Scale Test of Coping-Girder Integrated Bridge

Authors: Heeyoung Lee, Woosung Bin, Kangseog Seo, Hyojeong Yun, Zuog An

Abstract:

Recently, a new continuous bridge system has been proposed to increase the space under the bridge and to improve aesthetic aspect of the urban area. The main feature of the proposed bridge is to connect steel I-girders and coping by means of prestressed high-strength steel bars and steel plate. The proposed bridge is able to lower the height of the bridge to ensure the workability and efficiency through a reduction of the cost of road construction. This study presents the experimental result of the full-scale connection between steel I-girders and coping under the negative bending moment. The composite behavior is thoroughly examined and discussed under the specific load levels such as service load, factored load and crack load. Structural response showed full composite action until the final load level because no relative displacement between coping and girder was observed. It was also found prestressing force into high-strength bars was able to control tensile stresses of deck slab. This indicated that cracks in deck slab can be controlled by above-mentioned prestressing force.

Keywords: coping, crack, integrated bridge, full-scale test

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4325 Iterative Solver for Solving Large-Scale Frictional Contact Problems

Authors: Thierno Diop, Michel Fortin, Jean Deteix

Abstract:

Since the precise formulation of the elastic part is irrelevant for the description of the algorithm, we shall consider a generic case. In practice, however, we will have to deal with a non linear material (for instance a Mooney-Rivlin model). We are interested in solving a finite element approximation of the problem, leading to large-scale non linear discrete problems and, after linearization, to large linear systems and ultimately to calculations needing iterative methods. This also implies that penalty method, and therefore augmented Lagrangian method, are to be banned because of their negative effect on the condition number of the underlying discrete systems and thus on the convergence of iterative methods. This is in rupture to the mainstream of methods for contact in which augmented Lagrangian is the principal tool. We shall first present the problem and its discretization; this will lead us to describe a general solution algorithm relying on a preconditioner for saddle-point problems which we shall describe in some detail as it is not entirely standard. We will propose an iterative approach for solving three-dimensional frictional contact problems between elastic bodies, including contact with a rigid body, contact between two or more bodies and also self-contact.

Keywords: frictional contact, three-dimensional, large-scale, iterative method

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4324 Energy and Exergy Analysis of Anode-Supported and Electrolyte–Supported Solid Oxide Fuel Cells Gas Turbine Power System

Authors: Abdulrazzak Akroot, Lutfu Namli

Abstract:

Solid oxide fuel cells (SOFCs) are one of the most promising technologies since they can produce electricity directly from fuel and generate a lot of waste heat that is generally used in the gas turbines to promote the general performance of the thermal power plant. In this study, the energy, and exergy analysis of a solid oxide fuel cell/gas turbine hybrid system was proceed in MATLAB to examine the performance characteristics of the hybrid system in two different configurations: anode-supported model and electrolyte-supported model. The obtained results indicate that if the fuel utilization factor reduces from 0.85 to 0.65, the overall efficiency decreases from 64.61 to 59.27% for the anode-supported model whereas it reduces from 58.3 to 56.4% for the electrolyte-supported model. Besides, the overall exergy reduces from 53.86 to 44.06% for the anode-supported model whereas it reduces from 39.96 to 33.94% for the electrolyte-supported model. Furthermore, increasing the air utilization factor has a negative impact on the electrical power output and the efficiencies of the overall system due to the reduction in the O₂ concentration at the cathode-electrolyte interface.

Keywords: solid oxide fuel cell, anode-supported model, electrolyte-supported model, energy analysis, exergy analysis

Procedia PDF Downloads 142
4323 Study of Non-hodgkin’s Lymphoma

Authors: Zidani Abla

Abstract:

Lymphoma is a common type of cancer that affects the lymphatic system, including the lymph nodes, spleen and other associated organs. There are two main types of lymphoma: Hodgkin's lymphoma and non-Hodgkin's lymphoma. The epidemiological, clinical and biological features of lymphoma are poorly studied in Algeria. The main objective of our study is to investigate the epidemiological, clinical, paraclinical, etiological, evolutionary and biological characteristics of non-Hodgkin's lymphoma (NHL) in the hematology department of the University Hospital Center (HUC) of Batna. This is a study of 10 patients diagnosed at Batna University Hospital. 70% were male and 30% female (sex ratio M/F= 2.33). Median age was 51.7 years. Pain, especially abdominal pain, was the main reason for consultation. Stage IV predominated (40%), followed by stage III (20%). Abdominal adenopathies (34%) were the most abundant. Secondary hepatic localization was predominant. Large B-cell NHL predominated, accounting for 60% of cases, followed by small B-cell NHL (30%). Serology for hepatitis B and C, and human immunodeficiency virus (HIV) was negative. Biologically, a predominance of hyperleukocytosis, polynuclear neutrophilic leukocytosis, lymphopenia and hypoalbuminemia were present in the majority of cases. In summary, our results remain to be compared with other works for other periods and other regions in order to generalize lymphoma percentages for the entire Algerian population.

Keywords: non Hodgkin's lymphoma, epidemiology, clinic, biology

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4322 Harnessing the Benefits and Mitigating the Challenges of Neurosensitivity for Learners: A Mixed Methods Study

Authors: Kaaryn Cater

Abstract:

People vary in how they perceive, process, and react to internal, external, social, and emotional environmental factors; some are more sensitive than others. Compassionate people have a highly reactive nervous system and are more impacted by positive and negative environmental conditions (Differential Susceptibility). Further, some sensitive individuals are disproportionately able to benefit from positive and supportive environments without necessarily suffering negative impacts in less supportive environments (Vantage Sensitivity). Environmental sensitivity is underpinned by physiological, genetic, and personality/temperamental factors, and the phenotypic expression of high sensitivity is Sensory Processing Sensitivity. The hallmarks of Sensory Processing Sensitivity are deep cognitive processing, emotional reactivity, high levels of empathy, noticing environmental subtleties, a tendency to observe new and novel situations, and a propensity to become overwhelmed when over-stimulated. Several educational advantages associated with high sensitivity include creativity, enhanced memory, divergent thinking, giftedness, and metacognitive monitoring. High sensitivity can also lead to some educational challenges, particularly managing multiple conflicting demands and negotiating low sensory thresholds. A mixed methods study was undertaken. In the first quantitative study, participants completed the Perceived Success in Study Survey (PSISS) and the Highly Sensitive Person Scale (HSPS-12). Inclusion criteria were current or previous postsecondary education experience. The survey was presented on social media, and snowball recruitment was employed (n=365). The Excel spreadsheets were uploaded to the statistical package for the social sciences (SPSS)26, and descriptive statistics found normal distribution. T-tests and analysis of variance (ANOVA) calculations found no difference in the responses of demographic groups, and Principal Components Analysis and the posthoc Tukey calculations identified positive associations between high sensitivity and three of the five PSISS factors. Further ANOVA calculations found positive associations between the PSISS and two of the three sensitivity subscales. This study included a response field to register interest in further research. Respondents who scored in the 70th percentile on the HSPS-12 were invited to participate in a semi-structured interview. Thirteen interviews were conducted remotely (12 female). Reflexive inductive thematic analysis was employed to analyse data, and a descriptive approach was employed to present data reflective of participant experience. The results of this study found that compassionate students prioritize work-life balance; employ a range of practical metacognitive study and self-care strategies; value independent learning; connect with learning that is meaningful; and are bothered by aspects of the physical learning environment, including lighting, noise, and indoor environmental pollutants. There is a dearth of research investigating sensitivity in the educational context, and these studies highlight the need to promote widespread education sector awareness of environmental sensitivity, and the need to include sensitivity in sector and institutional diversity and inclusion initiatives.

Keywords: differential susceptibility, highly sensitive person, learning, neurosensitivity, sensory processing sensitivity, vantage sensitivity

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4321 Review of Urban Vitality in China: Exploring the Theoretical Framework, Characteristics, and Assessment Systems

Authors: Dong Wei, Wu Jinxiu

Abstract:

As China's urban construction enters a new phase of 'stock optimization,' the key point of urban development has shifted to the development and reuse of existing public space. However, cities still face a series of challenges, such as the shortage of space quantity and insufficient space quality, which indirectly affect urban vitality. A review of the vitality of urban public space will significantly contribute to optimizing the quality of the urban built environment. It firstly analyses the research hotspots of urban vitality at home and abroad, based on a semi-systematic literature review. Then this paper summarizes the theoretical definitions of the vitality of urban public space and sorts out the influencing factors from the perspectives of society, environment, and users. Lastly, the paper concludes with the mainstream quantitative and evaluation methods, such as linear evaluation and integrated evaluation. This paper renders a multi-theoretical perspective to understand the characteristics and evaluation system of the vitality of public space, which helps to acknowledge the dynamic relationship between users, urban environment, and vitality. It also looks forward to providing optimal design strategies for constructing a vigorous public space in future cities.

Keywords: public space, quantification of vitality, spatial vitality, urban vitality

Procedia PDF Downloads 93
4320 Improvement of Bone Scintography Image Using Image Texture Analysis

Authors: Yousif Mohamed Y. Abdallah, Eltayeb Wagallah

Abstract:

Image enhancement allows the observer to see details in images that may not be immediately observable in the original image. Image enhancement is the transformation or mapping of one image to another. The enhancement of certain features in images is accompanied by undesirable effects. To achieve maximum image quality after denoising, a new, low order, local adaptive Gaussian scale mixture model and median filter were presented, which accomplishes nonlinearities from scattering a new nonlinear approach for contrast enhancement of bones in bone scan images using both gamma correction and negative transform methods. The usual assumption of a distribution of gamma and Poisson statistics only lead to overestimation of the noise variance in regions of low intensity but to underestimation in regions of high intensity and therefore to non-optional results. The contrast enhancement results were obtained and evaluated using MatLab program in nuclear medicine images of the bones. The optimal number of bins, in particular the number of gray-levels, is chosen automatically using entropy and average distance between the histogram of the original gray-level distribution and the contrast enhancement function’s curve.

Keywords: bone scan, nuclear medicine, Matlab, image processing technique

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4319 Community-Based Destination Sustainable Development: Case of Cicada Walking Street, Hua Hin, Thailand

Authors: Kingkan Pongsiri

Abstract:

This paper aims to study the role and activities of the participants and the impact of activities created in the local area in order to sustainably develop the local areas. This study applied both qualitative and quantitative approaches presented in descriptive style; the data was collected via survey, observation and in-depth interviews with samples. The results illustrated five sorts of roles of participants of the Cicada Walking-street and four types of creative activities; recreation based, art based, cultural based, and live events. Integration of local characteristics, arts and cultures were presented creatively and interestingly. Participants are various. The roles of the participants found in the Cicada Market are group of the property and area management, entrepreneurs, leisure (entertaining persons), local people, and tourists. The good impacts on local communities are those in terms of economy, environmental friendly and local arts and cultures promoting. On the other hand, the traffic congestion, waste and the increasing of energy consumption are negative impacts from area development.

Keywords: creative tourism activity, destination development, sustainable development, walking street

Procedia PDF Downloads 236
4318 Ethical Consumers, The Myth or the Reality?: The Effects of Ethics in CSR on Corporate Authenticity and Pro-Firm Behaviours

Authors: K. Shim, J. N. Kim

Abstract:

This study investigates how consumers’ evaluations of a multinational corporation’s corporate social responsibility program connected to the perceived corporate authenticity and consumers’ pro-firm behavioral intention. With special attention to the two different types of CSR motives, business-oriented CSR motive and society-oriented motive, the current study empirically tests a theoretical model of a mediating role of corporate authenticity between perception of CSR motives and the consumers’ subsequent pro-firm behaviours. Results indicate significant mediation effects of corporate authenticity between perception of altruistic and societal CSR motives and consumers’ pro-firm behaviours. Unlike previous notions of the negative influence of self-interested motives on corporate authenticity, perceived strategic and business-oriented motives in CSR does not negatively affect the evalution of corporate authenticity when stakeholders have utilitarian ethical perspectives. Unlike the Korean participants, US participants are not willing to conduct pro-firm behaviors when they perceive strategic and business-oriented CSR motives. Theoretical and practical implications are discussed.

Keywords: corporate authenticity, corporate social responsibility, CSR motives, strategic CSR, utilitarian ethics, kantian ethics

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4317 Genotoxic and Cytotoxic Effects of Methidathion Pesticide

Authors: Mohammad Y. Alfaifi

Abstract:

Methidathion (MTD) (Trade name Supracide®) is a non-systemic organophosphorus insecticide used intensively worldwide including Saudi Arabia. However, there is a lack in published studies about it's genotoxicity. In this study we evaluated MTD toxicity in rat bone marrow cells (in vivo) and in lymphocytes (in vitro) using different doses based on LD50. MNNCE (Micronucleated normocromatic erythrocytes) and MNPCE (Micronucleated polychromatic erythrocytes), NDI (Nuclear division index) and NDCI (nuclear division cytotoxicity index), necrotic and apoptotic cells were recorded in rat's bone marrow samples. CA, MI (number of cells undergoing mitosis) necrotic, and apoptotic cells recorded in lymphocytes. Results showed that there was a slight increase in the frequency of micronucleated bone marrow cells. However, no structural chromosomal aberrations were detected in vivo or in vitro. On the other hand, the results showed significant increase in necrotic and apoptotic cells following MTD administration in a dose-dependent manner comparing to positive and negative control groups. In light of these results, MTD can be considered highly cytotoxic and moderate genotoxic, and precaution should be taken when using MTD.

Keywords: methidathion, micronucleus, NDI, NDCI, toxicity, chromosomal aberrations

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4316 Surfactant-Free O/W-Emulsion as Drug Delivery System

Authors: M. Kumpugdee-Vollrath, J.-P. Krause, S. Bürk

Abstract:

Most of the drugs used for pharmaceutical purposes are poorly water-soluble drugs. About 40% of all newly discovered drugs are lipophilic and the numbers of lipophilic drugs seem to increase more and more. Drug delivery systems such as nanoparticles, micelles or liposomes are applied to improve their solubility and thus their bioavailability. Besides various techniques of solubilization, oil-in-water emulsions are often used to incorporate lipophilic drugs into the oil phase. To stabilize emulsions surface active substances (surfactants) are generally used. An alternative method to avoid the application of surfactants was of great interest. One possibility is to develop O/W-emulsion without any addition of surface active agents or the so called “surfactant-free emulsion or SFE”. The aim of this study was to develop and characterize SFE as a drug carrier by varying the production conditions. Lidocaine base was used as a model drug. The injection method was developed. Effects of ultrasound as well as of temperature on the properties of the emulsion were studied. Particle sizes and release were determined. The long-term stability up to 30 days was performed. The results showed that the surfactant-free O/W emulsions with pharmaceutical oil as drug carrier can be produced.

Keywords: emulsion, lidocaine, Miglyol, size, surfactant, light scattering, release, injection, ultrasound, stability

Procedia PDF Downloads 473
4315 Study of Heat Exchangers in Small Modular Reactors

Authors: Harish Aryal, Roger Hague, Daniel Sotelo, Felipe Astete Salinas

Abstract:

This paper presents a comparative study of different coolants, materials, and temperatures that can affect the effectiveness of heat exchangers that are used in small modular reactors. The corrugated plate heat exchangers were chosen out of different plate options for testing purposes because of their ease of access and better performance than other existing heat exchangers in recent years. SolidWorks enables us to see various results between water coolants and helium coolants acting upon different types of conducting metals, which were selected from different fluids that ultimately satisfied accessibility requirements and were compatible with the software. Though not every element, material, fluid, or method was used in the testing phase, their purpose is to help further research that is to come since the innovation of nuclear power is the future. The tests that were performed are to help better understand the constant necessities that are seen in heat exchangers and through every adjustment see what the breaking points or improvements in the machine are. Depending on consumers and researchers, the results may give further feedback as to show why different types of materials and fluids would be preferred and why it is necessary to keep failures to improve future research.

Keywords: heat exchangers, Solidworks, coolants, small modular reactors, nuclear power, nanofluids, Nusselt number, friction factor, Reynolds number

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4314 On Erosion-Corrosion Behavior of Carbon Steel in Oil Sands Slurry: Electrochemical Studies

Authors: M. Deyab, A. Al-Sabagh, S. Keera

Abstract:

The effects of flow velocity, sand concentration, sand size and temperature on erosion-corrosion of carbon steel in oil sands slurry were studied by electrochemical polarization measurements. It was found that the anodic excursion spans of carbon steel in oil sands slurry are characterized by the occurrence of a well-defined anodic peak, followed by a passive region. The data reveal that increasing flow velocity, sand concentration and temperature enhances the anodic peak current density (jAP) and shifts pitting potential (Epit) towards more negative values. The variation of sand particle size does not have apparent effect on polarization behavior of carbon steel. The ratios of the erosion rate to corrosion rate (E/C) were calculated and discussed. The ratio of erosion to corrosion rates E/C increased with increasing the flow velocity, sand concentration, sand size and temperature indicating that an increasing slurry flow velocity, sand concentration, sand size and temperature resulted in an enhancement of the erosion effect.

Keywords: erosion-corrosion, steel, oil sands slurry, polarization

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4313 Support and Development of SMEs in the Slovak Republic: Selected Issues

Authors: Alexander Kelisek, Stanislava Strelcova

Abstract:

Developing of business in small and medium-sized enterprises (SMEs) is a specific especially for its flexibility and rapid adaptation to the conditions of turbulent market environment compared to large enterprises. Therefore, an importance of SMEs is growing rapidly in Slovakia but also in other EU countries. Small and medium enterprises are characterized by transparent organizational structure, as it allows the realization of direct management and information flow without significant negative aspects. In the national economy small and medium-sized enterprises represent a significant potential when performs a several important functions (e.g. social, economic, export-import, etc.) The significance of these enterprises is not only at national, but also at transnational level. Importance of SMEs is also aware of the EU, which declared this statement in a key document for SMEs called Small Business Act. In this document, SMEs are characterized, as the backbone of the EU economy and also as a key source of jobs opportunities. In addition to these aspects, SMEs attaches high innovation and development potential. The authors of the article are dealing with the current status of SMEs development in the Slovak Republic and highlight the current challenges that entrepreneurs face in their small and medium enterprises.

Keywords: small and medium enterprises (SMEs), business support, SMEs development, SMEs funding

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4312 Oxidation of Amitriptyline by Bromamine-T in Acidic Buffer Medium: A Kinetic and Mechanistic Approach

Authors: Chandrashekar, R. T. Radhika, B. M. Venkatesha, S. Ananda, Shivalingegowda, T. S. Shashikumar, H. Ramachandra

Abstract:

The kinetics of the oxidation of amitriptyline (AT) by sodium N-bromotoluene sulphonamide (C6H5SO2NBrNa) has been studied in an acidic buffer medium of pH 1.2 at 303 K. The oxidation reaction of AT was followed spectrophotometrically at maximum wavelength, 410 nm. The reaction rate shows a first order dependence each on concentration of AT and concentration of sodium N-bromotoluene sulphonamide. The reaction also shows an inverse fractional order dependence at low or high concentration of HCl. The dielectric constant of the solvent shows negative effect on the rate of reaction. The addition of halide ions and the reduction product of BAT have no significant effect on the rate. The rate is unchanged with the variation in the ionic strength (NaClO4) of the medium. Addition of reaction mixtures to be aqueous acrylamide solution did not initiate polymerization, indicating the absence of free radical species. The stoichiometry of the reaction was found to be 1:1 and oxidation product of AT is identified. The Michaelis-Menton type of kinetics has been proposed. The CH3C6H5SO2NHBr has been assumed to be the reactive oxidizing species. Thermodynamical parameters were computed by studying the reactions at different temperatures. A mechanism consistent with observed kinetics is presented.

Keywords: amitriptyline, bromamine-T, kinetics, oxidation

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4311 The Correlation between of Medicine and Postural Orthostatic Tachycardia Syndrome (POTS)

Authors: Dian Ariyawati, Romi Sukoco, Sinung Agung Joko

Abstract:

Background: Postural Orthostatic Tachycardia Syndrome (POTS) is a form of orthostatic intolerance caused by autonomic dysfunction. POTS predominantly occurs in young women. Regular exercise has proven to improve the organ system functions, including autonomous systems. The aim of this research was to determine the correlation between exercise frequency and POTS in young women. Method: 510 young women (16-23 years of age) were screened. They were obtained by interview and physical examination. The diagnosis of POTS was performed with Active Stand Test (AST) and heart rate measurement using a pulsemeter. There were 29 young women who suffered from POTS. The exercise frequency was obtained by interview. Data was statistically analyzed using Spearman Correlation test. Result: The subjects’, who tested positive for POTS didn’t perform regular exercise. The Spearman correlation test showed there was a moderate negative correlation between exercise frequency and POTS in young women (r = -0.487, p < 0.00). Conclusion: There is a moderate reverse correlation between exercise frequency and POTS in young women. Further studies are suggested to develop an exercise program for young who suffered from POTS.

Keywords: POTS, autonomic dysfunction, exercise frequency, young woman

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4310 A Multiple Freezing/Thawing Cycles Influence Internal Structure and Mechanical Properties of Achilles Tendon

Authors: Martyna Ekiert, Natalia Grzechnik, Joanna Karbowniczek, Urszula Stachewicz, Andrzej Mlyniec

Abstract:

Tendon grafting is a common procedure performed to treat tendon rupture. Before the surgical procedure, tissues intended for grafts (i.e., Achilles tendon) are stored in ultra-low temperatures for a long time and also may be subjected to unfavorable conditions, such as repetitive freezing (F) and thawing (T). Such storage protocols may highly influence the graft mechanical properties, decrease its functionality and thus increase the risk of complications during the transplant procedure. The literature reports on the influence of multiple F/T cycles on internal structure and mechanical properties of tendons stay inconclusive, confirming and denying the negative influence of multiple F/T at the same time. An inconsistent research methodology and lack of clear limit of F/T cycles, which disqualifies tissue for surgical graft purposes, encouraged us to investigate the issue of multiple F/T cycles by the mean of biomechanical tensile tests supported with Scanning Electron Microscope (SEM) imaging. The study was conducted on male bovine Achilles tendon-derived from the local abattoir. Fresh tendons were cleaned of excessive membranes and then sectioned to obtained fascicle bundles. Collected samples were randomly assigned to 6 groups subjected to 1, 2, 4, 6, 8 and 12 cycles of freezing-thawing (F/T), respectively. Each F/T cycle included deep freezing at -80°C temperature, followed by thawing at room temperature. After final thawing, thin slices of the side part of samples subjected to 1, 4, 8 and 12 F/T cycles were collected for SEM imaging. Then, the width and thickness of all samples were measured to calculate the cross-sectional area. Biomechanical tests were performed using the universal testing machine (model Instron 8872, INSTRON®, Norwood, Massachusetts, USA) using a load cell with a maximum capacity of 250 kN and standard atmospheric conditions. Both ends of each fascicle bundle were manually clamped in grasping clamps using abrasive paper and wet cellulose wadding swabs to prevent tissue slipping while clamping and testing. Samples were subjected to the testing procedure including pre-loading, pre-cycling, loading, holding and unloading steps to obtain stress-strain curves for representing tendon stretching and relaxation. The stiffness of AT fascicles bundle samples was evaluated in terms of modulus of elasticity (Young’s modulus), calculated from the slope of the linear region of stress-strain curves. SEM imaging was preceded by chemical sample preparation including 24hr fixation in 3% glutaraldehyde buffered with 0.1 M phosphate buffer, washing with 0.1 M phosphate buffer solution and dehydration in a graded ethanol solution. SEM images (Merlin Gemini II microscope, ZEISS®) were taken using 30 000x mag, which allowed measuring a diameter of collagen fibrils. The results confirm a decrease in fascicle bundles Young’s modulus as well as a decrease in the diameter of collagen fibrils. These results confirm the negative influence of multiple F/T cycles on the mechanical properties of tendon tissue.

Keywords: biomechanics, collagen, fascicle bundles, soft tissue

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4309 Selective Oxidation of Ammonia to Nitrogen over Nickel Oxide-hydroxide /Graphite Prepared with an Electro Deposition Method

Authors: Marzieh Joda, Narges Fallah, Neda Afsham

Abstract:

Graphite-supported two different of morphology α and β -Ni (OH)₂ electrodes were prepared by electrochemical deposition at appropriate potentials with regard to Ni (II)/Ni (III) redox couple under alkaline and acidic conditions, respectively, for selective oxidation of ammonia to nitrogen in the direct electro-oxidation process. Cyclic voltammetry (CV) of the electrolyte containing NH₃ indicated mediation of electron transfer by Ni (OH)₂ and the electrode surface was analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectrometer (RS), and X-ray photoelectron spectroscopy (XPS). Results of surface characterization indicated the presence of α polymorphs which is the stable phase of Ni (OH)₂ /Graphite. Cyclic voltammograms gave information on the nature of electron transfer between nitrogen species and working electrode and revealed that the potential has depended on both nature ammonia oxidation and that of concentration. The mechanism of selective ammonia conversion to nitrogen and byproducts, namely NO₂- and NO₃- was established by Cyclic voltammograms and current efficiency. The removal efficiency and selective conversion of ammonia (0.1 M KNO₃ + 0.01 M Ni(NO₃)₂, pH 11, 250°C) on Nickel Oxide-hydroxide /Graphite was determined based on potential controlled experiments.

Keywords: Electro deposition, Nickel oxide-hydroxide, Nitrogen selectivity, Ammonia oxidation

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4308 Investigation of Medicinal Applications of Maclura Pomifera Extract

Authors: Mahdi Asghari Ozma

Abstract:

Background and Objective:Maclurapomifera (Rafin.) Schneider, known as osage orange, is a north american native plant which has multiple applications in herbal medicine. The extract of this plant has many therapeutic effects, including antimicrobial, anti-tumor, anti-inflammation, etc., that discussed in this study. Materials and Methods: For this study, the keywords "Maclurapomifera", "osage orange, ""herbal medicine ", and "plant extract" in the databases PubMed and Google Scholar between 2002 and 2021 were searched, and 20 articles were chosen, studied and analyzed. Results: Due to the increased resistance of microbes to antibiotics, the need for antimicrobial plants is increasing. Maclurapomifera is one of the plants with antimicrobial properties that can affect all microbes, especially Gram-negative bacteria, and fungi. This plant also has anti-tumor, anti-inflammatory, anti-oxidant, anti-aging, antiviral, anti-fungal, anti-ulcerogenic, anti-diabetic, and anti-nociceptive effects, which can be used as a substance with many amazing therapeutic applications. Conclusion: These results suggest that the extract of Maclurapomifera can be used in clinical medicine as a remedial agent, which can be substituted for chemical drugs or help them in the treatment of diseases.

Keywords: maclura pomifera, osage orange, herbal medicine, plant extract

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4307 Analyzing the Perception of Students and Faculty Members on Social Media Use in Academic Activities: A Case Study of Beijing Normal University

Authors: Mcjerry A. Bekoe, Emile Uwamahoro

Abstract:

Social media has become the order of the day, in particular among the youth. It is widely used both formally and informally in the university communities with varied definitions both in the academic circles and in the public domain. In simple terms, it is a media upon which social interactions are carried. In this work social media denote mobile phones, and web-base applications use by students and institutions to construct, partake, and distribute both existing and new information in a digital setting through internet communication. The basic aim of conducting this study was to analyze the perception of students and faculty members Beijing Normal University on social media use in the academic setting and to contribute to the understanding of how university students use social media, the advantages and disadvantages of social media in education. The study was qualitative and employed open-ended interview questions developed to seek students’ perception of the effects of social media and administered based on purposive sampling. Document analysis was also done because of triangulation to ensure validity and reliability. The results show there are positive and negative impacts of social media use depending on how one uses it. Social media have the capability to become a priceless asset to aid their educational communication.

Keywords: academics, high education, interactions, social media

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4306 α-Amylase Inhibitory Activity of Some Tunisian Aromatic and Medicinal Plants

Authors: Hamdi Belfeki, Belgacem Chandoul, Mnasser Hassouna, Mondher Mejri

Abstract:

Aqueous and ethanolic extracts of eight Tunisian aromatic and medicinal plants (TAMP) were characterized by studying their composition in polyphenols and also their antiradical and antioxidant capacities. In absence and in the presence of the various extracts, α-amylase from Bacillus subtlis activity, was measured in order to detect a potential inhibition. The total contents of polyphenols and flavonoid vary in function of TAMP and the mobile phase used for the extraction (distilled water or ethanol). The ethanolic extracts showed the most significant antiradical and antioxidant activities. Only the extracts from Coriandrum sativum showed a significant inhibiting effect on the α-amylase activity. This inhibiting capacity could be correlated with the chemical profile of the two extracts, due to the fact that they have the greatest amount of total flavonoid. The ethanolic extract has the most important antioxidant and anti-radicalizing activities among the sixteen extracts studied. The inhibition kinetics of the two coriander extracts were evaluated by pre-incubation method, using Lineweaver-Burk’s equation, obtained by linearization of Michaeilis-Menten’s expression. The results showed that both extracts exercised a competitive inhibition mechanism.

Keywords: α-amylase, antioxidant activity, aromatic and medicinal plants, inhibition

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4305 Effect of Aeration on Co-Composting of Mixture of Food Waste with Sawdust and Sewage Sludge from Nicosia Waste Water Treatment Plant

Authors: Azad Khalid, Ime Akanyeti

Abstract:

About 68% of the urban solid waste generated in Turkish Republic of Northern Cyprus TRNC is household solid waste, at present, its disposal in landfills. In other hand more than 3000 ton per year of sewage sludge produces in Nicosia waste water treatment plant, the produced sludge piled up without any processing. Co-composting of organic fraction of municipal solid waste and sewage sludge is diverting of municipal solid waste from landfills and best disposal of wastewater sewage sludge. Three 10 L insulated bioreactor R1, R2 and R3 obtained with aeration rate 0.05 m3/h.kg for R2 and R3, R1 was without aeration. The mixture was destined with ratio of sewage sludge: food waste: sawdust; 1:5:0.8 (w/w). The effective of aeration monitored during 42 days of process through investigation in key parameter moisture, C/N ratio, temperature and pH. Results show that the high moisture content cause problem and around 60% recommend, C/N ratio decreased about 17% in aerated reactors and 10% in without aeration and mixture volume reduced in volume 40% in final compost with size of 1.00 to 20.0 mm. temperature in reactors with aeration reached thermophilic phase above 50 °C and <40 °C in without aeration. The final pH is 6.1 in R1, 8.23 in R2 and 8.1 in R3.

Keywords: aeration, sewage sludge, food waste, sawdust, composting

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4304 Work Engagement Reducing Employee Turnover Intentions in Telecommunication Sector: The Moderator Role of Human Resource Development Climate between Work Engagement and Turnover Intentions

Authors: Pirzada Sami Ullah Sabri

Abstract:

The present study examines the relationship between work engagement (WE) and employee turnover intentions (TI) in telecommunication sector using human resource development climate (HRDC) as a moderator. Based on 538 employees of telecommunication sector Hierarchal regression analysis is employed to examine the influence of HRDC on the relationship of work engagement and turnover intentions. The result indicates the negative correlation between work engagement and turnover intentions; HRD climate support as a powerful moderator increases the work engagement and lessens the turnover intentions. The study shows the importance of favorable and supportive HRD climate which foster the work engagement of the employees in the organization. By understanding the importance of human resource development climate and work engagement in reducing the turnover intentions can increase the productivity and performance of the organization.

Keywords: turnover intentions, work engagement, human resource development, climate, hierarchal regression analysis, telecommunication sector

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4303 Analyze and Improve Project Delivery Time Enhancing Business Management System of Review and Approval Process for Project Design Submittals

Authors: Abdulaziz Alnajem, Amit Sharma

Abstract:

Business Case: Project delivery and enhancing activities' completion in the shortest possible time is critical during execution to proceed with the subsequent phases of Procurement, C & C phases of Contracts to have the required Production facilities/Infrastructure in place to achieve the Company strategic objective of 4.0 MBOPD oil production. SOR (Statement of requirement): Design and Engineering phase of Projects execution takes a long time. It is observed that, in most of the cases, company has crossed the Project Design Submittals review time as per the Contract/Company Standards, resulting into delays in projects completion, and cost impact to the company. Study Scope: Scope of the study covers the process from date of first submission of D & E documents by the contractor to final approval by the controlling team to proceed with the procurement of materials. This scope covers projects handled by the company’s project management teams and includes only the internal review process by the company.

Keywords: business management system, project management, oil and gas, analysis, improvement, design, delays

Procedia PDF Downloads 204
4302 The Effects of Consumer Inertia and Emotions on New Technology Acceptance

Authors: Chyi Jaw

Abstract:

Prior literature on innovation diffusion or acceptance has almost exclusively concentrated on consumers’ positive attitudes and behaviors for new products/services. Consumers’ negative attitudes or behaviors to innovations have received relatively little marketing attention, but it happens frequently in practice. This study discusses consumer psychological factors when they try to learn or use new technologies. According to recent research, technological innovation acceptance has been considered as a dynamic or mediated process. This research argues that consumers can experience inertia and emotions in the initial use of new technologies. However, given such consumer psychology, the argument can be made as to whether the inclusion of consumer inertia (routine seeking and cognitive rigidity) and emotions increases the predictive power of new technology acceptance model. As data from the empirical study find, the process is potentially consumer emotion changing (independent of performance benefits) because of technology complexity and consumer inertia, and impact innovative technology use significantly. Finally, the study presents the superior predictability of the hypothesized model, which let managers can better predict and influence the successful diffusion of complex technological innovations.

Keywords: cognitive rigidity, consumer emotions, new technology acceptance, routine seeking, technology complexity

Procedia PDF Downloads 281
4301 Parametric and Analysis Study of the Melting in Slabs Heated by a Laminar Heat Transfer Fluid in Downward and Upward Flows

Authors: Radouane Elbahjaoui, Hamid El Qarnia

Abstract:

The present work aims to investigate numerically the thermal and flow characteristics of a rectangular latent heat storage unit (LHSU) during the melting process of a phase change material (PCM). The LHSU consists of a number of vertical and identical plates of PCM separated by rectangular channels. The melting process is initiated when the LHSU is heated by a heat transfer fluid (HTF: water) flowing in channels in a downward or upward direction. The proposed study is motivated by the need to optimize the thermal performance of the LHSU by accelerating the charging process. A mathematical model is developed and a fixed-grid enthalpy formulation is adopted for modeling the melting process coupling with convection-conduction heat transfer. The finite volume method was used for discretization. The obtained numerical results are compared with experimental, analytical and numerical ones found in the literature and reasonable agreement is obtained. Thereafter, the numerical investigations were carried out to highlight the effects of the HTF flow direction and the aspect ratio of the PCM slabs on the heat transfer characteristics and thermal performance enhancement of the LHSU.

Keywords: PCM, TES, LHSU, melting

Procedia PDF Downloads 249
4300 Disagreement in Spousal Report of Current Contraceptive Use in India and Its Determinants

Authors: Dipti Govil, Nidhi Khosla

Abstract:

Couple-level reports of contraception are important as wives and husbands may give different reports about contraceptive use. Using matched couple-data (N=62910), from India's NFHS–IV (2015-16), this paper examines concordance in spousal reports of current contraceptive use and its differentials. Reporting of contraceptive use was higher among wives (59%) than husbands (25%). Concordance was low; 16.5% of couples reported the use of the same method, while 21% reported the use of any method. There existed a huge denial from husbands on the use of female sterilization. Reconstruction of contraceptive use among men increased concordance by 10%. Multivariate analysis shows that concordance was low in urban and Southern India, among younger women and women with lower wealth-index. Men's control over household decision-making and negative attitudes towards contraception were associated with a lower concordance. Findings highlight the importance of using couple-level data to estimate contraceptive prevalence, the role of education programs to inculcate positive attitudes towards contraception, fostering gender equality, and involving men into family planning efforts. The results also raise the issue of data quality as the questions were asked differently from men and women, which might have contributed to wide discordance.

Keywords: concordance, contraceptive use, couple, female sterilisation, India

Procedia PDF Downloads 116
4299 Chemical Composition, Antioxidant and Antimicrobial Activities of the Essential Oils of Different Pinus Species from Kosovo

Authors: Fatbardhë Kurti, Giangiacomo Beretta, Behxhet Mustafa, Fabrizio Gelmini, Avni Hajdari

Abstract:

Chemical profile, antioxidant and antimicrobial activity of total and fractionated essential oils (EOs) (F1 – hexane, F2 – hexane/diethyl ether, F3 – diethyl ether) derived from five Pinus species (Pinus heldreichii, P. peuce, P. mugo, Pinus nigra, P. sylvestris), were investigated. The hydrodistilled EOs and their chromatographic fractions (direct solid phase extraction, SPE) were analysed by GC-MS and 112 compounds separated and identified. The main constituents were α-pinene, β-pinene, D-limonene, β-caryophyllene, germacrene D, bornyl acetate and 3-carene. The antioxidant activities of total EOs were lower than those of the corresponding fractions, with F2 the strongest in all cases. EOs and fractions showed different degrees of antibacterial efficacy against different microbial pathogens (moderately strong antimicrobial activity against C. albicans and C. krusei ,while low or no activity against E. faecalis and E. coli strains). The detected inhibition zones and MICs for the EOs and fractions were in the range of 14 -35 mm and 0.125 - 1% (v/v), respectively. The components responsible for the antioxidant and antimicrobial activity were oxygenated monoterpenes and sesquiterpenes recovered in the polar EO fractions. These activities seem to be regulated by reciprocal interactions among the different subclasses of phytochemical species present in the EOs.

Keywords: antagonism, antioxidant activity, antibacterial activity, essential oil, fractions, GC-MS, pinus

Procedia PDF Downloads 213
4298 Housing Recovery in Heavily Damaged Communities in New Jersey after Hurricane Sandy

Authors: Chenyi Ma

Abstract:

Background: The second costliest hurricane in U.S. history, Sandy landed in southern New Jersey on October 29, 2012, and struck the entire state with high winds and torrential rains. The disaster killed more than 100 people, left more than 8.5 million households without power, and damaged or destroyed more than 200,000 homes across the state. Immediately after the disaster, public policy support was provided in nine coastal counties that constituted 98% of the major and severely damaged housing units in NJ overall. The programs include Individuals and Households Assistance Program, Small Business Loan Program, National Flood Insurance Program, and the Federal Emergency Management Administration (FEMA) Public Assistance Grant Program. In the most severely affected counties, additional funding was provided through Community Development Block Grant: Reconstruction, Rehabilitation, Elevation, and Mitigation Program, and Homeowner Resettlement Program. How these policies individually and as a whole impacted housing recovery across communities with different socioeconomic and demographic profiles has not yet been studied, particularly in relation to damage levels. The concept of community social vulnerability has been widely used to explain many aspects of natural disasters. Nevertheless, how communities are vulnerable has been less fully examined. Community resilience has been conceptualized as a protective factor against negative impacts from disasters, however, how community resilience buffers the effects of vulnerability is not yet known. Because housing recovery is a dynamic social and economic process that varies according to context, this study examined the path from community vulnerability and resilience to housing recovery looking at both community characteristics and policy interventions. Sample/Methods: This retrospective longitudinal case study compared a literature-identified set of pre-disaster community characteristics, the effects of multiple public policy programs, and a set of time-variant community resilience indicators to changes in housing stock (operationally defined by percent of building permits to total occupied housing units/households) between 2010 and 2014, two years before and after Hurricane Sandy. The sample consisted of 51 municipalities in the nine counties in which between 4% and 58% of housing units suffered either major or severe damage. Structural equation modeling (SEM) was used to determine the path from vulnerability to the housing recovery, via multiple public programs, separately and as a whole, and via the community resilience indicators. The spatial analytical tool ArcGIS 10.2 was used to show the spatial relations between housing recovery patterns and community vulnerability and resilience. Findings: Holding damage levels constant, communities with higher proportions of Hispanic households had significantly lower levels of housing recovery while communities with households with an adult >age 65 had significantly higher levels of the housing recovery. The contrast was partly due to the different levels of total public support the two types of the community received. Further, while the public policy programs individually mediated the negative associations between African American and female-headed households and housing recovery, communities with larger proportions of African American, female-headed and Hispanic households were “vulnerable” to lower levels of housing recovery because they lacked sufficient public program support. Even so, higher employment rates and incomes buffered vulnerability to lower housing recovery. Because housing is the "wobbly pillar" of the welfare state, the housing needs of these particular groups should be more fully addressed by disaster policy.

Keywords: community social vulnerability, community resilience, hurricane, public policy

Procedia PDF Downloads 361
4297 Sympathetic Cooling of Antiprotons with Molecular Anions

Authors: Sebastian Gerber, Julian Fesel, Christian Zimmer, Pauline Yzombard, Daniel Comparat, Michael Doser

Abstract:

Molecular anions play a central role in a wide range of fields: from atmospheric and interstellar science, anionic superhalogens to the chemistry of highly correlated systems. However, up to now the synthesis of negative ions in a controlled manner at ultracold temperatures, relevant for the processes in which they are involved, is currently limited to a few Kelvin by supersonic beam expansion followed by resistive, buffer gas or electron cooling in cryogenic environments. We present a realistic scheme for laser cooling of C2- molecules to sub-Kelvin temperatures, which has so far only been achieved for a few neutral diatomic molecules. The generation of a pulsed source of C2- and subsequent laser cooling techniques of C2- molecules confined in a Penning trap are reviewed. Further, laser cooling of one anionic species would allow to sympathetically cool other molecular anions, electrons and antiprotons that are confined in the same trapping potential. In this presentation the status of the experiment and the feasibility of C2- sympathetic Doppler laser cooling, photo-detachment cooling and AC-Stark Sisyphus cooling will be reviewed.

Keywords: antiprotons, anions, cooling of ions and molecules, Doppler cooling, photo-detachment, penning trap, Sisyphus cooling, sympathetic cooling

Procedia PDF Downloads 367