Search results for: religious strain
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2558

Search results for: religious strain

938 Microstructure and Corrosion Properties of Pulsed Current Gas Metal Arc Welded Narrow Groove and Ultra-Narrow Groove of 304 LN Austenitic Stainless Steel

Authors: Nikki A. Barla, P. K. Ghosh, Sourav Das

Abstract:

Two different groove sizes 13.6 mm (narrow groove) and 7.5 mm (ultra-narrow groove) of 304 LN austenitic stainless steel (ASS) plate was welded using pulse gas metal arc welding (P-GMAW). These grooves were welded using multi-pass single seam per layer (MSPPL) deposition technique with full assurance of groove wall fusion. During bead on plate deposition process, the thermal cycle was recorded using strain buster (temperature measuring device). Both the groove has heat affected Zone (HAZ) width of 1-2 mm. After welding, the microstructure studies was done which revealed that there was higher sensitization (Chromium carbide formation in grain boundary) in the HAZ of 13.6 mm groove weldment as compared to the HAZ of 7.5 mm weldment. Electrochemical potentiokinetic reactivation test (EPR) was done in 0.5 N H₂SO₄ + 1 M KSCN solution to study the degree of sensitization (DOS) and it was observed that 7.5 mm groove HAZ has lower DOS. Mass deposition in the 13.6 mm weld is higher than 7.5mm groove weld, which naturally induces higher residual stress in 13.6 mm weld. Comparison between microstructural studies and corrosion test summarized that the residual stress affects the sensitization property of welded ASS.

Keywords: austenitic stainless steel (ASS), electrochemical potentiokinetic reactivation test (EPR), microstructure, pulse gas metal arc welding (P-GMAW), sensitization

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937 Structural Performance of Composite Steel and Concrete Beams

Authors: Jakub Bartus

Abstract:

In general, composite steel and concrete structures present an effective structural solution utilizing full potential of both materials. As they have a numerous advantages on the construction side, they can reduce greatly the overall cost of construction, which is the main objective of the last decade, highlighted by the current economic and social crisis. The study represents not only an analysis of composite beams’ behaviour having web openings but emphasizes the influence of these openings on the total strain distribution at the level of steel bottom flange as well. The major investigation was focused on a change of structural performance with respect to various layouts of openings. Examining this structural modification, an improvement of load carrying capacity of composite beams was a prime object. The study is devided into analytical and numerical part. The analytical part served as an initial step into the design process of composite beam samples, in which optimal dimensions and specific levels of utilization in individual stress states were taken into account. The numerical part covered description of imposed structural issue in a form of a finite element model (FEM) using strut and shell elements accounting for material non-linearities. As an outcome, a number of conclusions were drawn describing and explaining an effect of web opening presence on the structural performance of composite beams.

Keywords: composite beam, web opening, steel flange, totalstrain, finite element analysis

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936 Future Applications of 4D Printing in Dentistry

Authors: Hosamuddin Hamza

Abstract:

The major concept of 4D printing is self-folding under thermal and humidity changes. This concept relies on understanding how the microstructures of 3D-printed models can undergo spontaneous shape transformation under thermal and moisture changes. The transformation mechanism could be achieved by mixing, in a controllable pattern, a number of materials within the printed model, each with known strain/shrinkage properties. 4D printing has a strong potential to be applied in dentistry as the technology could produce dynamic and adaptable materials to be used as functional objects in the oral environment under the continuously changing thermal and humidity conditions. The motion criteria could override the undesired dimensional changes, thermal instability, polymerization shrinkage and microleakage. 4D printing could produce restorative materials being self-adjusted spontaneously without further intervention from the dentist or patient; that is, the materials could be capable of fixing its failed portions, compensating for some lost tooth structure, while avoiding microleakage or overhangs at the margins. In prosthetic dentistry, 4D printing could provide an option to manage the influence of bone and soft tissue imbalance during mastication (and at rest) with high predictability of the type/direction of forces. It can also produce materials with better fitting and retention characteristics than conventional or 3D-printed materials. Nevertheless, it is important to highlight that 4D-printed objects, having dynamic properties, could provide some cushion as they undergo self-folding compensating for any thermal changes or mechanical forces such as traumatic forces.

Keywords: functional material, self-folding material, 3D printing, 4D printing

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935 The Arts of Walisanga's Mosques in Java: Structure/Architecture Studies and Its Meaning in Anthropological Perspective

Authors: Slamet Subiyantoro, Mulyanto

Abstract:

Revealing the structure and symbolism meaning of the walisanga’s mosque arts in Java is very important to explain the philosophy of religious foundation which is a manifestation of the norms/ value system and behavior of the Javanese Islam society that support the culture. This research's aims are also to find the structure pattern of walisanga’s mosque and its symbolic meaning in the context of Javanese Islam society. In order to obtain the research objectives, the research were done in several walisanga’s mosques in Java using anthropological approach which is focused on its interpretation and semiotic analysis. The data were collected through interviews with key informants who well informed about the shape and symbolism of walisanga’s mosques in Java. The observation technique is done through visiting walisanga’s mosques to see directly about its structure/ architecture. In completing the information of comprehensive result of the research, it is also used documents and archives as well as any other source which is analyzed to deepen the discussion in answering the problems research. The flow of analysis is done using an interactive model through stages of data collection, data reduction, data presentation and verification. The analysis is done continuously in a cycle system to draw valid conclusions. The research result indicates that the structure/architecture of walisanga’s mosque in Java is structured/built up vertically as well as horizontally. Its structure/architecture is correlated to each other which is having a sacred meaning that is a process represents the mystical belief such as sangkan paraning dumadi and manuggaling kawula gusti.

Keywords: Walisanga’s mosques, Java, structure and architecture, meaning

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934 On Being a Fugitive from the State-Sponsored Witch Hunt of Homosexuals in Egypt's Media Discourse

Authors: Mahitab A. A. Mahmoud

Abstract:

Despite the international community’s galvanized efforts to achieve gender equality, the Arab world still lags behind for their sustained suppression of diversity and freedoms. In Egypt, homosexuals are defamed and hunted not only by authorities but also by politicized religious institutions and media platforms. The resultant state-sponsored homophobia is reflected in media. This paper offers a critical discourse analysis of the representation of LGBTQs in Egypt’s local news articles and movies in an attempt to investigate the underlying ideology. The results reveal a clichéd portrayal of homosexuals as a social parasite that requires cleansing by the government. LGBTQs are depicted as an outcome of debauchery, unhappy marriage, sexual deviancy, deficiency of masculinity/femininity, absence of the mother and/or father figure(s), abject poverty, excessive wealth, psychiatric disorder, debased instincts, childhood sexual molestation, immorality, deviation from religion, chaos, treason, conspiracy against the regime, to name only a few. This image, which is imposed and sustained by the state, exposes homosexuals to a violation of their human rights by both the police and the society, endangers their lives, breeds intolerance, social inequality and violence, prevents healthy coexistence; and deprives them of living a normal life.

Keywords: critical discourse analysis, gender studies, homophobia, homosexuality, ideology, media studies

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933 Thermoplastic Polyurethane/Barium Titanate Composites

Authors: Seyfullah Madakbaş, Ferhat Şen, Memet Vezir Kahraman

Abstract:

The aim of this study was to improve thermal stability, mechanical and surface properties of thermoplastic polyurethane (TPU) with the addition of BaTiO3. The TPU/ BaTiO3 composites having various ratios of TPU and BaTiO3 were prepared. The chemical structure of the prepared composites was investigated by FT-IR. FT-IR spectra of TPU/ barium titanate composites show that they successfully were prepared. Thermal stability of the samples was evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The prepared composites showed high thermal stability, and the char yield increased as barium titanate content increased. The glass transition temperatures of the composites rise with the addition of barium titanate. Mechanical properties of the samples were characterized with stress-strain test. The mechanical properties of the TPU were increased with the contribution of the contribution of the barium titanate it increased. Hydrophobicity of the samples was determined by the contact angle measurements. The contact angles have the tendency to increase the hydrophobic behavior on the surface, when barium titanate was added into TPU. Moreover, the surface morphology of the samples was investigated by a scanning electron microscopy (SEM). SEM-EDS mapping images showed that barium titanate particles were dispersed homogeneously. Finally, the obtained results prove that the prepared composites have good thermal, mechanical and surface properties and that they can be used in many applications such as the electronic devices, materials engineering and other emergent.

Keywords: barium titanate, composites, thermoplastic polyurethane, scanning electron microscopy

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932 Water Gas Shift Activity of PtBi/CeO₂ Catalysts for Hydrogen Production

Authors: N. Laosiripojana, P. Tepamatr

Abstract:

The influence of bismuth on the water gas shift activities of Pt on ceria was studied. The flow reactor was used to study the activity of the catalysts in temperature range 100-400°C. The feed gas composition contains 5%CO, 10% H₂O and balance N₂. The total flow rate was 100 mL/min. The outlet gas was analyzed by on-line gas chromatography with thermal conductivity detector. The catalytic activities of bimetallic 1%Pt1%Bi/CeO₂ catalyst were greatly enhanced when compared with the activities of monometallic 2%Pt/CeO₂ catalyst. The catalysts were characterized by X-ray diffraction (XRD), Temperature-Programmed Reduction (TPR) and surface area analysis. X-ray diffraction pattern of Pt/CeO₂ and PtBi/CeO₂ indicated slightly shift of diffraction angle when compared with pure ceria. This result was due to strong metal-support interaction between platinum and ceria solid solution, causing conversion of Ce⁴⁺ to larger Ce³⁺. The distortions inside ceria lattice structure generated strain into the oxide lattice and facilitated the formation of oxygen vacancies which help to increase water gas shift performance. The H₂-Temperature Programmed Reduction indicated that the reduction peak of surface oxygen of 1%Pt1%Bi/CeO₂ shifts to lower temperature than that of 2%Pt/CeO₂ causing the enhancement of the water gas shift activity of this catalyst. Pt played an important role in catalyzing the surface reduction of ceria and addition of Bi alter the reduction temperature of surface ceria resulting in the improvement of the water gas shift activity of Pt catalyst.

Keywords: bismuth, platinum, water gas shift, ceria

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931 Effect of Different Carbon Fabric Orientations on the Fracture Properties of Carbon Fabric Reinforced Polymer Composites

Authors: S. F. Halim, H. F. Naguib, S. N. Lawandy, R. S. Hegazy, M. N. Baheg

Abstract:

The main drawbacks of the traditional carbon fabric reinforced epoxy resin (CFRP) are low strain failure, delamination between composites layers, and low impact resistance due to the brittleness of epoxy resin. The aim of this study is to enhance the fracture properties of the CFRP composites laminates via the variation of composite's designs. A series of composites were fabricated in which bidirectional (00/900) carbon fabric (CF) layers were laid inside the resin matrix with orientation codes as F1 [(00, 900)/ (00, 900)], F2 [(900, 00)/ (00, 900)] and F3 [(00,900)/ (900, 00). The mechanical and dynamic properties of the composites were estimated. In addition, the morphology of samples surface was examined by scanning electron microscope (SEM) after impact fracture. The results revealed that the CFRP properties could be tailored fitting specific applications by controlling the fabric orientation inside the CFRP composite design. F2 orientation [(900, 00)/ (00.900)] showed the highest tensile and flexural strength values. On the other hand, the impact strength values of composites were in the order F1 > F2 > F3. The storage modulus, loss modulus, and glass transition temperature Tg values obtained from the dynamic mechanical analysis (DMA) examination was in the order F1 > F2 > F3. The variation in the properties of the composite was clearly explained by the SEM micrographs as the failure of F3 orientation properties was referred to as the complete breakage of the CF layers upon fracture.

Keywords: carbon fiber, CFRP, composites, epoxy resins, flexural strength

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930 Finite Element Modeling and Mechanical Properties of Aluminum Proceed by Equal Channel Angular Pressing Process

Authors: F. Al-Mufadi, F. Djavanroodi

Abstract:

During the last decade ultrafine grained (UFG) and nano-structured (NS) materials have experienced a rapid development. In this research work finite element analysis has been carried out to investigate the plastic strain distribution in equal channel angular process (ECAP). The magnitudes of standard deviation (S. D.) and inhomogeneity index (Ci) were compared for different ECAP passes. Verification of a three-dimensional finite element model was performed with experimental tests. Finally the mechanical property including impact energy of ultrafine grained pure commercially pure Aluminum produced by severe plastic deformation method has been examined. For this aim, equal channel angular pressing die with the channel angle, outer corner angle and channel diameter of 90°, 20° and 20 mm had been designed and manufactured. Commercial pure Aluminum billets were ECAPed up to four passes by route BC at the ambient temperature. The results indicated that there is a great improvement at the hardness measurement, yield strength and ultimate tensile strength after ECAP process. It is found that the magnitudes of HV reach 67 HV from 21 HV after the final stage of process. Also, about 330% and 285% enhancement at the YS and UTS values have been obtained after the fourth pass as compared to the as-received conditions, respectively. On the other hand, the elongation to failure and impact energy have been reduced by 23% and 50% after imposing four passes of ECAP process, respectively.

Keywords: SPD, ECAP, FEM, pure Al, mechanical properties

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929 The Socio-Religious, Economic, and Cultural Impacts of Aso-Ebi on South-East Nigeria

Authors: Nwaoga, Theresa Chinyere

Abstract:

The paper examines the impacts of Aso-Ebi, a Yoruba term for ‘uniform’ on the people of south-east Nigeria. Aso-Ebi is used to denote uniform wear which is typical of the people of south-west Nigeria. In the 1980s and 1990s, uniform wears were used only by immediate family members of a deceased person. This is for easy identification by visitors—to know those who are related to the deceased person. Aso-Ebi is now part of a culture that has existed in Nigeria from the Yoruba and transcended to other parts of Nigeria, precisely south-east Nigeria. The buying of Aso-Ebi and attending the occasions in the attire is the only way of showing solidarity and support to the celebrant. Aso-Ebi has led to creating a sense of belonging, opening of doors for marriage by those single, and fundraising. As part of the findings, it was discovered that Aso-Ebi has led to an increase in marital infidelity and divorce, robbery, prostitution, depression, and an increase in enmity between friends in south-east Nigeria. Data was generated through oral interviews, focus group discussion and participant observation. Secondary data were obtained from journals, textbooks, the internet and periodicals. The phenomenological method of research was used as the methodology. This method allows for an objective report and analysis of the research problem. Aso-Ebi has come to stay in Igbo culture, so there should be a proper re-orientation on the uses of Aso-Ebi during occasions like burial in Igbo land. The campaign can start from the church by discouraging people from using Aso-Ebi during burials and wedding ceremonies.

Keywords: Asho Ebi, uniformed women, burial ceremonies, August meetings

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928 Manipulation of Ideological Items in the Audiovisual Translation of Voiced-Over Documentaries in the Arab World

Authors: S. Chabbak

Abstract:

In a widely globalized world, the influence of audiovisual translation on the culture and identity of audiences is unmistakable. However, in the Arab World, there is a noticeable disproportion between this growing influence and the research carried out in the field. As a matter of fact, the voiced-over documentary is one of the most abundantly translated genres in the Arab World that carries lots of ideological elements which are in many cases rendered by manipulation. However, voiced-over documentaries have hardly received any focused attention from researchers in the Arab World. This paper attempts to scrutinize the process of translation of voiced-over documentaries in the Arab World, from French into Arabic in the present case study, by sub-categorizing the ideological items subject to manipulation, identifying the techniques utilized in their translation and exploring the potential extra-linguistic factors that prompt translation agents to opt for manipulative translation. The investigation is based on a corpus of 94 episodes taken from a series entitled 360° GEO Reports, produced by the French German network ARTE in French, and acquired, translated and aired by Al Jazeera Documentary Channel for Arab audiences. The results yielded 124 cases of manipulation in four sub-categories of ideological items, and the use of 10 different oblique procedures in the process of manipulative translation. The study also revealed that manipulation is in most of the instances dictated by the editorial line of the broadcasting channel, in addition to the religious, geopolitical and socio-cultural peculiarities of the target culture.

Keywords: audiovisual translation, ideological items, manipulation, voiced-over documentaries

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927 The Complementary Explanations of Institutional and Feminist Perspectives for Female Social Enterprise in Pakistan

Authors: Mohammad Sohail Yunis, Hina Hashim, Alistair R. Anderson

Abstract:

Entrepreneurship is gendered with masculine qualities, yet social enterprise epitomizes caring a feminine quality. However enterprising practices may have little to do with gender. Consequently, the purpose of this paper is to examine practices using two very different explanatory theories, feminist and institutional theory, to establish the role played by gender. This study is situated in KP, the poor but traditional north of Pakistan. Utilising on an interpretive qualitative research approach, this research collected data through in-depth interviews with ten women social entrepreneurs of KP, Pakistan and analyzed using thematic analysis. Empirically, this paper identifies and describes on a number of interesting themes that relate to the women entrepreneurship such as 'women empowerment, patriarchal culture, role of culture and societal norms, religious extremism and terrorism, forced entrepreneurs, change creators, institutional corruption, and security issues'. In addition, female social enterprise in KP is set in a patriarchal, masculine culture, but the practices negotiate institutional obstacles to bring benefits to the disenfranchised. Finally, this research claims to present an original insight into female social entrepreneurship in a developing country context and provide fresh theoretical and empirical perspectives to advance knowledge and scholarship.

Keywords: female social entrepreneurship, institutional theory, feminist theory, developing countries

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926 Microbial Deterioration of Some Different Archaeological Objects Made from Cellulose by Bacillus Group

Authors: Mohammad Abdel Fattah Mohammad Kewisha

Abstract:

Microbial deterioration of ancient materials became one of the biggest problems facing the workers in the field of cultural heritage protection because the microbial deterioration of artifacts causes detrimental effects on the aesthetic value of the monuments due to colonization, whether they are made of inorganic materials such as stone or organic like wood, textiles, wall paintings, and paper. So, the early identification of the bacterial strains that caused deterioration is the most important point for the protection of monument objects. The present study focuses on the Bacillus spp. group, which was isolated from some biodeterioration monuments from different areas of Egypt. The investigated objects in this study were made from organic materials (cellulose), paper, textile, and wood. Isolated strains were identified up to the species level biochemically. Eleven bacterial isolates were obtained from collected samples. They were taken from different archaeological objects, four microbicides, cetrimonium bromide, sodium azide, tetraethyl ammonium bromide, and dichloroxylenol, at various concentrations ranging from 25 ppm to 500 ppm. They were screened for their antibacterial activity against the Bacillus spp. isolates, and detection of Minimum inhibitory concentration (MIC). It was also necessary to indicate the ideal Minimum inhibitory concentration for each strain for the purpose of biotreatment of the infected monuments with less damaging effect on monument materials.

Keywords: microbial deterioration, ancient materials, heritage protection, protection of monuments, biodeteriorative monuments

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925 Concerns for Extreme Climate Conditions and Their Implications in Southwest Nigeria

Authors: Oyenike Eludoyin

Abstract:

Extreme climate conditions are deviation from the norms and are capable of causing upsets in many important environmental parameter including disruption of water balance and air temperature balance. Studies have shown that extreme climate conditions can foretell disaster in regions with inadequate early warning systems. In this paper, we combined geographical information systems, statistics and social surveys to evaluate the physiologic indices [(Dewpoint Temperature (Td), Effective Temperature Index (ETI) and Relative Strain Index (RSI)] and extreme climate conditions in different parts of southwest Nigeria. This was with the view to assessing the nature and the impact of the conditions on the people and their coping strategies. The results indicate that minimum, mean and maximum temperatures were higher in 1960-1990 than 1991-2013 periods at most areas, and more than 80% of the people adapt to thermal stress by changing wear type or cloth, installing air conditioner and fan at home and/or work place and sleeping outside at certain period of the night and day. With respect to livelihoods, about 52% of the interviewed farmers indicated that too early rainfall, late rainfall, prolonged dryness after an initial rainfall, excessive rainfall and windstorms caused low crop yields. Main (76%) coping strategies were changing of planting dates, diversification of crops, and practices of mulching and intercropping. Government or institutional support was less than 20%.

Keywords: coping strategies, extreme climate, livelihoods, physiologic comfort

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924 Influence of Kinematic, Physical and Mechanical Structure Parameters on Aeroelastic GTU Shaft Vibrations in Magnetic Bearings

Authors: Evgeniia V. Mekhonoshina, Vladimir Ya. Modorskii, Vasilii Yu. Petrov

Abstract:

At present, vibrations of rotors of gas transmittal unit evade sustainable forecasting. This paper describes elastic oscillation modes in resilient supports and rotor impellers modeled during computational experiments with regard to interference in the system of gas-dynamic flow and compressor rotor. Verification of aeroelastic approach was done on model problem of interaction between supersonic jet in shock tube with deformed plate. ANSYS 15.0 engineering analysis system was used as a modeling tool of numerical simulation in this paper. Finite volume method for gas dynamics and finite elements method for assessment of the strain stress state (SSS) components were used as research methods. Rotation speed and material’s elasticity modulus varied during calculations, and SSS components and gas-dynamic parameters in the dynamic system of gas-dynamic flow and compressor rotor were evaluated. The analysis of time dependence demonstrated that gas-dynamic parameters near the rotor blades oscillate at 200 Hz, and SSS parameters at the upper blade edge oscillate four times higher, i.e. with blade frequency. It has been detected that vibration amplitudes correction in the test points at magnetic bearings by aeroelasticity may correspond up to 50%, and about -π/4 for phases.

Keywords: Centrifugal compressor, aeroelasticity, interdisciplinary calculation, oscillation phase displacement, vibration, nonstationarity

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923 Study of the Adhesive Bond Effect on Electro-Mechanical Behaviour of Coupled Piezo Structural System

Authors: Rahul S. Raj

Abstract:

Electro-mechanical impedance technique is a recently developed non-destructive method for structural health monitoring. This system comprises of piezo electric patch, bonded to the structure using an adhesive/epoxy and electrically excited to determine the health of the component. The subjected electric field actuates the PZT patch harmonically and imparts a force on the host structure. The structural response thus produced by the host component is in the form of peaks and valleys which further shows the admittance signatures of the structure for the given excitation frequency. Adhesives have the capability to change the structural signatures, in EMI technique, by transforming conductance and susceptance signatures. The static approximation provide a justifiable result where adhesive bond lines are thin and stiff. The epoxy adhesive bonds limits design flexibility due to poor bond strengths, hence to enhance the performance of the joints, a new technique is developed for joining PZT, i.e. the alloy bonding technique. It is a metallic joining compound which contains many active elements including Titanium, that reacts with the tenacious surface films of the ceramic and composites to create excellent bonds. This alloy-based bonding technique will be used for better strain interaction and rigorous stress transfer between PZT patch and the host structure.

Keywords: EMI technique, conductance, susceptance, admittance, alloy bonding

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922 A Novel Protein Elicitor Extracted From Lecanicillium lecanii Induced Resistance Against Whitefly, Bemisia tabaci in Cotton

Authors: Yusuf Ali Abdulle, Azhar Uddin Keerio

Abstract:

Background: Protein elicitors play a key role in signaling or displaying plant defense mechanisms and emerging as vital tools for bio-control of insects. This study was aimed at the characterization of the novel protein elicitor isolated from entomopathogenic fungi Lecanicillium lecanii (V3) strain and its activity against Whitefly, Bemisia tabaci in cotton. The sequence of purified elicitor protein showed 100% similarity with hypothetical protein LEL_00878 [Cordyceps confragosa RCEF 1005], GenBank no (OAA81333.1). This novel protein elicitor has 253 amino acid residues and 762bp with a molecular mass of 29 kDa. The protein recombinant was expressed in Escherichia coli using pET‐28a (+) plasmid. Effects of purified novel protein elicitor on Bemisia tabaci were determined at three concentrations of protein (i.e., 58.32, 41.22, 35.41 μg mL⁻¹) on cotton plants and were exposed to newly molted adult B.tabaci. Bioassay results showed a significant effect of the exogenous application of novel protein elicitor on B. tabaci in cotton. In addition, the gene expression analysis found a significant up-regulation of the major genes associated with salicylic acid (SA) and jasmonic acid (JA) linked plant defense pathways in elicitor protein-treated plants. Our results suggested the potential application of a novel protein elicitor derived from Lecanicillium lecanii as a future bio-intensive controlling approach against the whitefly, Bemisia tabaci.

Keywords: resistance, Lecanicillium lecanii, secondary metabolites, whitefly

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921 Investigation of Fire Damaged Concrete Using Nonlinear Resonance Vibration Method

Authors: Kang-Gyu Park, Sun-Jong Park, Hong Jae Yim, Hyo-Gyung Kwak

Abstract:

This paper attempts to evaluate the effect of fire damage on concrete by using nonlinear resonance vibration method, one of the nonlinear nondestructive method. Concrete exhibits not only nonlinear stress-strain relation but also hysteresis and discrete memory effect which are contained in consolidated materials. Hysteretic materials typically show the linear resonance frequency shift. Also, the shift of resonance frequency is changed according to the degree of micro damage. The degree of the shift can be obtained through nonlinear resonance vibration method. Five exposure scenarios were considered in order to make different internal micro damage. Also, the effect of post-fire-curing on fire-damaged concrete was taken into account to conform the change in internal damage. Hysteretic non linearity parameter was obtained by amplitude-dependent resonance frequency shift after specific curing periods. In addition, splitting tensile strength was measured on each sample to characterize the variation of residual strength. Then, a correlation between the hysteretic non linearity parameter and residual strength was proposed from each test result.

Keywords: nonlinear resonance vibration method, non linearity parameter, splitting tensile strength, micro damage, post-fire-curing, fire damaged concrete

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920 Isolation and Identification of Novel Escherichia Marmotae Spp.: Their Enzymatic Biodegradation of Zearalenone and Deep-oxidation of Deoxynivalenol

Authors: Bilal Murtaza, Xiaoyu Li, Liming Dong, Muhammad Kashif Saleemi, Gen Li, Bowen Jin, Lili Wang, Yongping Xu

Abstract:

Fusarium spp. produce numerous mycotoxins, such as zearalenone (ZEN), deoxynivalenol (DON), and its acetylated compounds, 3-acetyl-deoxynivalenol (3-ADON) and 15-acetyl-deoxynivalenol (15-ADON) (15-ADON). In a co-culture system, the soil-derived Escherichia marmotae strain degrades ZEN and DON into 3-keto-DON and DOM-1 via enzymatic deep-oxidation. When pure mycotoxins were subjected to Escherichia marmotae in culture flasks, degradation, and detoxification were also attained. DON and ZEN concentrations, ambient pH, incubation temperatures, bacterium concentrations, and the impact of acid treatment on degradation were all evaluated. The results of the ELISA and high-performance liquid chromatography-electrospray ionization-high resolution mass spectrometry (HPLC-ESI-HRMS) tests demonstrated that the concentration of mycotoxins exposed to Escherichia marmotae was significantly lower than the control. ZEN levels were reduced by 43.9%, while zearalenone sulfate ([M/z 397.1052 C18H21O8S1) was discovered as a derivative of ZEN converted by microbes to a less toxic molecule. Furthermore, Escherichia marmotae appeared to metabolize DON 35.10% into less toxic derivatives (DOM-1 at m/z 281 of [DON - O]+ and 3-keto-DON at m/z 295 of [DON - 2H]+). These results show that Escherichia marmotae can reduce Fusarium mycotoxins production, degrade pure mycotoxins, and convert them to less harmful compounds, opening up new possibilities for study and innovation in mycotoxin detoxification.

Keywords: mycotoxins, zearalenone, deoxynivalenol, bacterial degradation

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919 A Structural Constitutive Model for Viscoelastic Rheological Behavior of Human Saphenous Vein Using Experimental Assays

Authors: Rassoli Aisa, Abrishami Movahhed Arezu, Faturaee Nasser, Seddighi Amir Saeed, Shafigh Mohammad

Abstract:

Cardiovascular diseases are one of the most common causes of mortality in developed countries. Coronary artery abnormalities and carotid artery stenosis, also known as silent death, are among these diseases. One of the treatment methods for these diseases is to create a deviatory pathway to conduct blood into the heart through a bypass surgery. The saphenous vein is usually used in this surgery to create the deviatory pathway. Unfortunately, a re-surgery will be necessary after some years due to ignoring the disagreement of mechanical properties of graft tissue and/or applied prostheses with those of host tissue. The objective of the present study is to clarify the viscoelastic behavior of human saphenous tissue. The stress relaxation tests in circumferential and longitudinal direction were done in this vein by exerting 20% and 50% strains. Considering the stress relaxation curves obtained from stress relaxation tests and the coefficients of the standard solid model, it was demonstrated that the saphenous vein has a non-linear viscoelastic behavior. Thereafter, the fitting with Fung’s quasilinear viscoelastic (QLV) model was performed based on stress relaxation time curves. Finally, the coefficients of Fung’s QLV model, which models the behavior of saphenous tissue very well, were presented.

Keywords: Viscoelastic behavior, stress relaxation test, uniaxial tensile test, Fung’s quasilinear viscoelastic (QLV) model, strain rate

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918 Temperature-Stable High-Speed Vertical-Cavity Surface-Emitting Lasers with Strong Carrier Confinement

Authors: Yun Sun, Meng Xun, Jingtao Zhou, Ming Li, Qiang Kan, Zhi Jin, Xinyu Liu, Dexin Wu

Abstract:

Higher speed short-wavelength vertical-cavity surface-emitting lasers (VCSELs) working at high temperature are required for future optical interconnects. In this work, the high-speed 850 nm VCSELs are designed, fabricated and characterized. The temperature dependent static and dynamic performance of devices are investigated by using current-power-voltage and small signal modulation measurements. Temperature-stable high-speed properties are obtained by employing highly strained multiple quantum wells and short cavity length of half wavelength. The temperature dependent photon lifetimes and carrier radiative times are determined from damping factor and resonance frequency obtained by fitting the intrinsic optical bandwidth with the two-pole transfer function. In addition, an analytical theoretical model including the strain effect is development based on model-solid theory. The calculation results indicate that the better high temperature performance of VCSELs can be attributed to the strong confinement of holes in the quantum wells leading to enhancement of the carrier transit time.

Keywords: vertical cavity surface emitting lasers, high speed modulation, optical interconnects, semiconductor lasers

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917 Machine Learning and Metaheuristic Algorithms in Short Femoral Stem Custom Design to Reduce Stress Shielding

Authors: Isabel Moscol, Carlos J. Díaz, Ciro Rodríguez

Abstract:

Hip replacement becomes necessary when a person suffers severe pain or considerable functional limitations and the best option to enhance their quality of life is through the replacement of the damaged joint. One of the main components in femoral prostheses is the stem which distributes the loads from the joint to the proximal femur. To preserve more bone stock and avoid weakening of the diaphysis, a short starting stem was selected, generated from the intramedullary morphology of the patient's femur. It ensures the implantability of the design and leads to geometric delimitation for personalized optimization with machine learning (ML) and metaheuristic algorithms. The present study attempts to design a cementless short stem to make the strain deviation before and after implantation close to zero, promoting its fixation and durability. Regression models developed to estimate the percentage change of maximum principal stresses were used as objective optimization functions by the metaheuristic algorithm. The latter evaluated different geometries of the short stem with the modification of certain parameters in oblique sections from the osteotomy plane. The optimized geometry reached a global stress shielding (SS) of 18.37% with a determination factor (R²) of 0.667. The predicted results favour implantability integration in the short stem optimization to effectively reduce SS in the proximal femur.

Keywords: machine learning techniques, metaheuristic algorithms, short-stem design, stress shielding, hip replacement

Procedia PDF Downloads 182
916 Finite Element Modeling of Friction Stir Welding of Dissimilar Alloys

Authors: Fadi Al-Badour, Nesar Merah, Abdelrahman Shuaib, Abdelaziz Bazoune

Abstract:

In the current work, a Coupled Eulerian Lagrangian (CEL) model is developed to simulate the friction stir welding (FSW) process of dissimilar Aluminum alloys (Al 6061-T6 with Al 5083-O). The model predicts volumetric defects, material flow, developed temperatures, and stresses in addition to tool reaction loads. Simulation of welding phase is performed by employing a control volume approach, whereas the welding speed is defined as inflow and outflow over Eulerian domain boundaries. Only material softening due to inelastic heat generation is considered and material behavior is assumed to obey Johnson-Cook’s Model. The model was validated using published experimentally measured temperatures, at similar welding conditions, and by qualitative comparison of dissimilar weld microstructure. The FE results showed that most of developed temperatures were below melting and that the bulk of the deformed material in solid state. The temperature gradient on AL6061-T6 side was found to be less than that of Al 5083-O. Changing the position Al 6061-T6 from retreating (Ret.) side to advancing (Adv.) side led to a decrease in maximum process temperature and strain rate. This could be due to the higher resistance of Al 6061-T6 to flow as compared to Al 5083-O.

Keywords: friction stir welding, dissimilar metals, finite element modeling, coupled Eulerian Lagrangian Analysis

Procedia PDF Downloads 314
915 Numerical Homogenization of Nacre

Authors: M. Arunachalam, M. Pandey

Abstract:

Nacre, a biological material that forms the inner-layer of sea shells can achieve high toughness and strength by way of staggered arrangement of strong tablets with soft and weak organic interface. Under applied loads the tablets slide over the adjacent tablets, thus generating inelastic deformation and toughness on macroscopic scale. A two dimensional finite element based homogenization methodology is adopted for obtaining the effective material properties of Nacre using a representative volume element (RVE) at finite deformations. In this work, the material behaviour for tablet and interface are assumed to be Isotropic elastic and Isotropic elastic-perfectly plastic with strain softening respectively. Numerical experiments such as uniaxial tension test along X, Y directions and simple shear test are performed on the RVE with uniform displacement and periodic constraints applied at the RVE boundaries to obtain the anisotropic homogenized response and maximum local stresses within each constituents of Nacre. Homogenized material model is then tested for macroscopic structure under three point bending condition and the results obtained are comparable with the results obtained for detailed microstructure based structure, thus homogenization provides a bridge between macroscopic scale and microscopic scale and homogenized material properties obtained from microstructural (RVE) analysis could be used in large scale structural analysis.

Keywords: finite element, homogenization, inelastic deformation, staggered arrangement

Procedia PDF Downloads 302
914 Assessment of Reproductive Toxicity of Diazinon Pesticide in Male Wistar Rats

Authors: Mohammad Alfaifi

Abstract:

Organophosphates are among the most widely used synthetic insect pesticides. The widespread use of organophosphates has stimulated research into the possible existence of effects related with their reproductive toxic activity. The present study aimed to assess the effects of diazinon (DIZ) on male reproductive system. DIZ at the dose levels of 1.5, 3.0 and 9.0 mg/kg b. wt./day was administered orally to male rats of Wistar strain for 30 days to evaluate the toxic alterations in testicular histology, biochemistry, sperm dynamics, and testosterone levels. The body weight of animals did not show any significant changes, however, a significant reduction was observed in testes weight. DIZ also brought about marked reduction in epididymal and testicular sperm counts in exposed males and a decrease in serum testosterone concentration. Histopathological examination of testes showed mild to severe degenerative changes in seminiferous tubules at various dose levels. Fertility test showed 79% negative results. All these toxic effects are moderate at low doses and become severe at higher dose levels. From the results of the present study it is concluded that DIZ induces severe testicular damage and results in reduction in sperm count and thus affect fertility. Small changes in sperm counts are known to have adverse affects on human fertility. Therefore, application of such insecticide should be limited to a designed programme.

Keywords: reproductive toxicity, fertility, diazinon, sperm count

Procedia PDF Downloads 304
913 Enhancements to the Coupled Hydro-Mechanical Hypoplastic Model for Unsaturated Soils

Authors: Shanujah Mathuranayagam, William Fuentes, Samanthika Liyanapathirana

Abstract:

This paper introduces an enhanced version of the coupled hydro-mechanical hypoplastic model. The model is able to simulate volumetric collapse upon wetting and incorporates suction effects on stiffness and strength. Its mechanical constitutive equation links Bishop’s effective stress with strain and suction, featuring a normal consolidation line (NCL) with a compression index (λ) presenting a non-linear dependency with the degree of saturation. The Bulk modulus has been modified to ensure that under rapid volumetric collapse, the stress state remains at the NCL. The coupled model comprises eighteen parameters, with nine for the hydraulic component and nine for the mechanical component. Hydraulic parameters are calibrated with the use of water retention curves (IWRC) across varied soil densities, while mechanical parameters undergo calibration using isotropic and triaxial tests on both unsaturated and saturated samples. The model's performance is analyzed through the back-calculation of two experimental studies: (i) wetting under different vertical stresses for Lower Cromer Till and (ii) isotropic loading and triaxial loading for undisturbed loess. The results confirm that the proposed model is able to predict the hydro-mechanical behavior of unsaturated soils.

Keywords: hypoplastic model, volumetric collapse, normal consolidation line, compression index (λ), degree of saturation, soil suction

Procedia PDF Downloads 44
912 A Viable Approach for Biological Detoxification of Non Edible Oil Seed Cakes and Their Utilization in Food Production Using Aspergillus Niger

Authors: Kshitij Bhardwaj, R.K. Trivedi, Shipra Dixit

Abstract:

We used biological detoxification method that converts toxic residue waste of Jatropha curcas oil seeds (non edible oil seed) into industrial bio-products and animal feed material. Present study describes the complete degradation of phorbol esters by Aspergillus Niger strain during solid state fermentation (SSF) of deoiled Jatropha curcas seed cake. Phorbol esters were completely degraded in 15 days under the optimized SSF conditions viz deoiled cake 5.0 gm moistened with 5.0 ml distilled water; inoculum 2 ml of overnight grown Aspergillus niger; incubated at 30◦ C, pH 7.0. This method simultaneously induces the production of Protease enzyme by Aspergillus Niger which has high potential to be used in feedstuffs .The maximum Protease activities obtained were 709.16 mg/ml in Jatropha curcas oil seed cake. The protein isolate had small amounts of phorbol esters, phytic acid, and saponin without any lectin. Its minimum and maximum solubility were at pH 4.0&12.0. Water and oil binding capacities were 3.22 g water/g protein and 1.86 ml oil/g protein respectively.Emulsion activity showed high values in a range of basic pH. We concluded that Jatropha Curcas seed cake has a potential to be used as a novel source of functional protein for food or feed applications.

Keywords: solid state fermentation, Jatropha curcas, oil seed cake, phorbol ester

Procedia PDF Downloads 464
911 The Socioeconomic and Moral Impacts of the Syrian Refugees to Turkey

Authors: Inci Aksu Kargin

Abstract:

The civil war which began in the Daraa province of Syria in March 2011, has caused thousands of Syrians to die and millions more to seek refuge in other countries such as Turkey, Lebanon, Jordan, Iraq, and Egypt. In order to understand the Syrian refugees’ living conditions and the problems they have experienced in Turkey in-depth, and to analyze how the arrival of the Syrian refugees in Turkey has affected the local people who live in Turkish-Syrian border, this study employed interviews, which were conducted with three different groups. First, 60 Syrian refugees, who have settled in Hatay and Gaziantep, were interviewed. Then, the Turkish government institutions, and NGOs, which are responsible for assisting the refugees, were interviewed. These interviews revealed that many Syrian refugees have encountered with several issues such as access to labor and housing markets as well as free healthcare and public education services. Second, 60 Turkish citizens living in Hatay and Gaziantep provinces were interviewed. These interviews shed light on the many issues (e.g., increase of unemployment, increase in the rental and sale prices of the houses, decrease in the quality of healthcare services, increase in traffic problems, problems with regard to the usage of parks and gardens) that Turkish citizens began experiencing after mass asylum claim of the Syrian refugees to Turkey. In addition to these, the existing social problems in Turkey such as child labor, begging, child brides, and illegal marriages (religious marriages) worsen.

Keywords: migration, refugees, Syrian civil war, Turkey

Procedia PDF Downloads 268
910 Evaluation of Reproductive Toxicity of Diazinon Pesticide in Male Wistar Rats

Authors: Mohammad Alfaifi, Mohammed Alshehri

Abstract:

Organophosphates are among the most widely used synthetic insect pesticides. The widespread use of organophosphates has stimulated research into the possible existence of effects related with their reproductive toxic activity. The present study aimed to assess the effects of diazinon (DIZ) on male reproductive system. DIZ at the dose levels of 1.5, 3.0 and 9.0 mg/kg b. wt./day was administered orally to male rats of Wistar strain for 30 days to evaluate the toxic alterations in testicular histology, biochemistry, sperm dynamics and testosterone levels. The body weight of animals did not show any significant changes; however, a significant reduction was observed in testes weight. DIZ also brought about a marked reduction in epididymal and testicular sperm counts in exposed males and a decrease in serum testosterone concentration. Histopathological examination of testes showed mild to severe degenerative changes in seminiferous tubules at various dose levels. Fertility test showed 79% negative results. All these toxic effects are moderate at low doses and become severe at higher dose levels. From the results of the present study, it is concluded that DIZ induces severe testicular damage and results in a reduction in sperm count and thus affect fertility. Small changes in sperm counts are known to have adverse effects on human fertility. Therefore, application of such insecticide should be limited to a designed programme.

Keywords: organophosphates, reproductive toxicity, diazinon, fertility

Procedia PDF Downloads 395
909 Displacement Fields in Footing-Sand Interactions under Cyclic Loading

Authors: S. Joseph Antony, Z. K. Jahanger

Abstract:

Soils are subjected to cyclic loading in situ in situations such as during earthquakes and in the compaction of pavements. Investigations on the local scale measurement of the displacements of the grain and failure patterns within the soil bed under the cyclic loading conditions are rather limited. In this paper, using the digital particle image velocimetry (DPIV), local scale displacement fields of a dense sand medium interacting with a rigid footing are measured under the plane-strain condition for two commonly used types of cyclic loading, and the quasi-static loading condition for the purposes of comparison. From the displacement measurements of the grains, the failure envelopes of the sand media are also presented. The results show that, the ultimate cyclic bearing capacity (qultcyc) occurred corresponding to a relatively higher settlement value when compared with that of under the quasi-static loading. For the sand media under the cyclic loading conditions considered here, the displacement fields in the soil media occurred more widely in the horizontal direction and less deeper along the vertical direction when compared with that of under the quasi-static loading. The 'dead zone' in the sand grains beneath the footing is identified for all types of the loading conditions studied here. These grain-scale characteristics have implications on the resulting bulk bearing capacity of the sand media in footing-sand interaction problems.

Keywords: cyclic loading, DPIV, settlement, soil-structure interactions, strip footing

Procedia PDF Downloads 147