Search results for: quasi-saturation effect
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14749

Search results for: quasi-saturation effect

12109 Effect of Pack Aluminising Conditions on βNiAl Coatings

Authors: A. D. Chandio, P. Xiao

Abstract:

In this study, nickel aluminide coatings were deposited onto CMSX-4 single crystal superalloy and pure Ni substrates by using in-situ chemical vapour deposition (CVD) technique. The microstructural evolutions and coating thickness (CT) were studied upon the variation of processing conditions i.e. time and temperature. The results demonstrated (under identical conditions) that coating formed on pure Ni contains no substrate entrapments and have lower CT in comparison to one deposited on the CMSX-4 counterpart. In addition, the interdiffusion zone (IDZ) of Ni substrate is a γ’-Ni3Al in comparison to the CMSX-4 alloy that is βNiAl phase. The higher CT on CMSX-4 superalloy is attributed to presence of γ-Ni/γ’-Ni3Al structure which contains ~ 15 at.% Al before deposition (that is already present in superalloy). Two main deposition parameters (time and temperature) of the coatings were also studied in addition to standard comparison of substrate effects. The coating formation time was found to exhibit profound effect on CT, whilst temperature was found to change coating activities. In addition, the CT showed linear trend from 800 to 1000 °C, thereafter reduction was observed. This was attributed to the change in coating activities.

Keywords: βNiAl, in-situ CVD, CT, CMSX-4, Ni, microstructure

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12108 Numerical Analysis of Geosynthetic-Encased Stone Columns under Laterally Loads

Authors: R. Ziaie Moayed, M. Hossein Zade

Abstract:

Out of all methods for ground improvement, stone column became more popular these days due to its simple construction and economic consideration. Installation of stone column especially in loose fine graded soil causes increasing in load bearing capacity and settlement reduction. Encased granular stone columns (EGCs) are commonly subjected to vertical load. However, they may also be subjected to significant amount of shear loading. In this study, three-dimensional finite element (FE) analyses were conducted to estimate the shear load capacity of EGCs in sandy soil. Two types of different cases, stone column and geosynthetic encased stone column were studied at different normal pressures varying from 15 kPa to 75 kPa. Also, the effect of diameter in two cases was considered. A close agreement between the experimental and numerical curves of shear stress - horizontal displacement trend line is observed. The obtained result showed that, by increasing the normal pressure and diameter of stone column, higher shear strength is mobilized by soil; however, in the case of encased stone column, increasing the diameter had more dominated effect in mobilized shear strength.

Keywords: encased stone column, laterally load, ordinary stone column, validation

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12107 Activation of AMPK-TSC axis is involved in cryptotanshinone inhibition of mTOR signaling in cancer cells

Authors: Wenxing Chen, Guangying Chen, Yin Lu, Shile Huang

Abstract:

Cryptotanshinone (CPT), a fat-soluble tanshinone from Salvia miltiorrhiza Bunge, has been demonstrated to inhibit mTOR pathway, resulting in inhibition of cancer cell proliferation. However, the molecular mechanism how CPT acts on mTOR is unknown. Here, cancer cells expressing rapamycin-resistant mutant mTOR are also sensitive to CPT, while phosphorylation of AMPK and TSC2 was activated, suggesting that CPT inhibition of mTOR maybe due to activating upstream of mTOR, AMPK, but not directly binding to and inhibiting mTOR. Further results indicated that Compound C, inhibitor of AMPK, could partially reversed CPT inhibition effect on cancer cells, and dominant-negative AMPK in cancer cells conferred resistance to CPT inhibition of 4EBP1 and phosphorylation of S6K1, as well as sh-AMPK. Furthermore, compared with MEF cells with AMPK positive, MEF cells with AMPK knock out are less sensitive to CPT by the findings that 4E-BP1 and phosphorylation of S6K1 express comparatively much. Furthermore, downexpression of TSC2 slightly recovered expression of 4EBP1 and phosphorylation of S6K1, while co-immunoprecipitation of TSC2 did not affect expression of TSC1 by CPT. Collectively, the above-mentioned results suggest that CPT inhibited mTOR pathway mostly was due to activation of AMPK-TSC2 pathway rather than specific inhibition of mTOR and then induction of subsequent lethal cellular effect.

Keywords: cryptotanshinone, AMPK, TSC2, mTOR, cancer cells

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12106 Acrylamide-Induced Acute Nephrotoxicity in Rats

Authors: Keivan Jamshidi, Afshin Zahedi

Abstract:

Acrylamide (ACR) has been shown to cause neurotoxic effects in humans and neurotoxic, genotoxic, reproductive, and carcinogenic effects in laboratory animals. To investigate the nephrotoxic effect of Acrylamide (ACR), 50 adult male rats (Wistar, approximately 250 g) housed in polycarbonate boxes as 5 per each, and randomly assigned in 5 groups including 4 exposure groups as A, B, C, and D groups of rats (10 rats per exposure group., total) and were exposed to 0.5, 5, 50, 100 mg/kg ACR per day×11days i.p. respectively. The remaining 10 rats were housed in group (E) as control group. Control rats received daily i.p. injections of 0.9% saline (3ml/kg). On day 12, four rats, were randomly selected, perfused , dissected and proper samples were collected from their kidneys. Results of histopathological studies based on H&E technique did show no morphologic changes in kidneys of rats belong to groups A, B and E, while moderate to severe morphologic changes including glomerular hypercellularity, global pattern of proliferative glomerulonephritis, occupation of capsular space, tubular cell swelling and hyaline cast formation, were observed in different stained sections obtained from the kidneys of rats belong to group, C, and D. This finding, beside neurotoxic, reproductive and carcinogenic effects, seems to indicate for the first time another important aspect of toxic effect of ACR, i.e., acute nephrotoxicity.

Keywords: acrylamide, nephrotoxicity, glomerulonephritis, rats

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12105 Effect of Al2O3 Nanoparticles on Corrosion Behavior of Aluminum Alloy Fabricated by Powder Metallurgy

Authors: Muna Khethier Abbass, Bassma Finner Sultan

Abstract:

In this research the effect of Al2O3 nanoparticles on corrosion behavior of aluminum base alloy(Al-4.5wt%Cu-1.5wt%Mg) has been investigated. Nanocomopsites reinforced with variable contents of 1,3 & 5wt% of Al2O3 nanoparticles were fabricated using powder metallurgy. All samples were prepared from the base alloy powders under the best powder metallurgy processing conditions of 6 hr of mixing time , 450 MPa of compaction pressure and 560°C of sintering temperature. Density and micro hardness measurements, and electrochemical corrosion tests are performed for all prepared samples in 3.5wt%NaCl solution at room temperature using potentiostate instrument. It has been found that density and micro hardness of the nanocomposite increase with increasing of wt% Al2O3 nanoparticles to Al matrix. It was found from Tafel extrapolation method that corrosion rates of the nanocomposites reinforced with alumina nanoparticles were lower than that of base alloy. From results of corrosion test by potentiodynamic cyclic polarization method, it was found the pitting corrosion resistance improves with adding of Al2O3 nanoparticles . It was noticed that the pits disappear and the hysteresis loop disappears also from anodic polarization curve.

Keywords: powder metallurgy, nano composites, Al-Cu-Mg alloy, electrochemical corrosion

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12104 The Development of the Prototype of Bamboo Shading Device

Authors: Nuanwan Tuaycharoen, Wanarat Konisranukul

Abstract:

The main aim of this research was to investigate the prototype of bamboo shading device. There were two objectives of this study. The first objective was to investigate the effect of non-chemical treatments on damage of bamboo shading device by powder-post beetle and fungi. The second aim of this study was to develop a prototype of bamboo shading device. The study of the effect of non-chemical treatments on damage of bamboo shading device by powder-post beetle in laboratory showed that, among seven treatments tested, wood vinegar treatment can protect powder-post beetle better than the original method up to 92.91%. It was also found that wood vinegar treatment can show the best performance in fungi protection and work better than the original method up to 40%. The second experiment was carried out by constructing four bamboo shading devices and installing them on a building for 28 days. All aspects of shading device were investigated in terms of their beauty, durability, and ease of construction and assembly. The final prototype was developed from the lessons drawn from these tested options. In conclusion this study showed the effectiveness of some natural preservatives against insect and fungi damage. It also illustrated the characteristics of the prototype of bamboo shading device that can constructed by rural workers within one week.

Keywords: bamboo, shading device, energy conservation, alternative material

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12103 Impact Deformation and Fracture Behaviour of Cobalt-Based Haynes 188 Superalloy

Authors: Woei-Shyan Lee, Hao-Chien Kao

Abstract:

The impact deformation and fracture behaviour of cobalt-based Haynes 188 superalloy are investigated by means of a split Hopkinson pressure bar. Impact tests are performed at strain rates ranging from 1×103 s-1 to 5×103 s-1 and temperatures between 25°C and 800°C. The experimental results indicate that the flow response and fracture characteristics of cobalt-based Haynes 188 superalloy are significantly dependent on the strain rate and temperature. The flow stress, work hardening rate and strain rate sensitivity all increase with increasing strain rate or decreasing temperature. It is shown that the impact response of the Haynes 188 specimens is adequately described by the Zerilli-Armstrong fcc model. The fracture analysis results indicate that the Haynes 188 specimens fail predominantly as the result of intensive localised shearing. Furthermore, it is shown that the flow localisation effect leads to the formation of adiabatic shear bands. The fracture surfaces of the deformed Haynes 188 specimens are characterised by dimple- and / or cleavage-like structure with knobby features. The knobby features are thought to be the result of a rise in the local temperature to a value greater than the melting point.

Keywords: Haynes 188 alloy, impact, strain rate and temperature effect, adiabatic shearing

Procedia PDF Downloads 359
12102 A Radiographic Survey of Eggshell Powder Effect on Tibial Bone Defect Repair Tested in Dog

Authors: M. Yadegari, M. Nourbakhsh, N. Arbabzadeh

Abstract:

The skeletal system injuries are of major importance. In addition, it is recommended to use materials for hard tissue repair in open or closed fractures. It is important to use complex minerals with a beneficial effect on hard tissue repair, stimulating cell growth in the bone. Materials that could help avoid bone fracture inflammatory reaction and speed up bone fracture repair are of utmost importance in the treatment of bone fractures. Similar to minerals, the inner eggshell membrane consists of carbohydrates, lipids, proteins with the high pH, high calcium absorptive capacity and with faster bone fracture repair ability. In the present radiographic survey, eggshell-derived bone graft substitutes were used for bone defect repair in 8 dog tibia, measuring bone density on the day of implant placement and 30 and 60 days after placement. In fact, the result of this study shows the difference in bone growth and misshapen bones between treatment and control sites. Cell growth was adequate in treatment sites and misshapen bones were less frequent here than in control sites.

Keywords: bone repair, eggshell powder, implant, radiography

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12101 Impact of Process Parameters on Tensile Strength of Fused Deposition Modeling Printed Crisscross Poylactic Acid

Authors: Shilpesh R. Rajpurohit, Harshit K. Dave

Abstract:

Additive manufacturing gains the popularity in recent times, due to its capability to create prototype as well functional as end use product directly from CAD data without any specific requirement of tooling. Fused deposition modeling (FDM) is one of the widely used additive manufacturing techniques that are used to create functional end use part of polymer that is comparable with the injection-molded parts. FDM printed part has an application in various fields such as automobile, aerospace, medical, electronic, etc. However, application of FDM part is greatly affected by poor mechanical properties. Proper selection of the process parameter could enhance the mechanical performance of the printed part. In the present study, experimental investigation has been carried out to study the behavior of the mechanical performance of the printed part with respect to process variables. Three process variables viz. raster angle, raster width and layer height have been varied to understand its effect on tensile strength. Further, effect of process variables on fractured surface has been also investigated.

Keywords: 3D Printing, fused deposition modeling, layer height, raster angle, raster width, tensile strength

Procedia PDF Downloads 197
12100 Effect of Gel Concentration on Physical Properties of an Electrochromic Device

Authors: Sharan K. Indrakar, Aakash B. Prasad, Arash Takshi, Sesha Srinivasan, Elias K. Stefanakos

Abstract:

In this work, we present an exclusive study on the effect of the feeding ratio of polyaniline-based redox-active gel layer on electrical and optical properties of innovative electrochromic devices (ECs). An electrochromic device consisting of polyaniline (PANI) has a redox-active gel electrolyte placed between two conducting transparent fluorine-doped tin oxide glass substrates. The redox-active composite gel is a mixture of different concentrations of aniline (monomer), a water-soluble polymer poly (vinyl alcohol), hydrochloric acid, and an oxidant. The EC device shows the color change from dark green to transparent for the applied potential between -0.5 V to +2.0 V. The coloration and decoloration of the ECs were tested for electrochemical behavior using techniques such as cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). The optical transparency of the EC devices was examined at two different biasing voltage conditions under UV-visible spectroscopic technique; the result showed 65% transmittance at 564 nm and zero transmittance when the cell was biased at 0.0 V and 2.0 V, the synthesized mol fraction gel was analyzed for surface morphology and structural properties by scanning electron microscopy and Fourier transformer spectroscopy.

Keywords: electrochromic, gel electrolyte, polyaniline, conducting polymer

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12099 The Effectiveness of Environmental Policy Instruments for Promoting Renewable Energy Consumption: Command-and-Control Policies versus Market-Based Policies

Authors: Mahmoud Hassan

Abstract:

Understanding the impact of market- and non-market-based environmental policy instruments on renewable energy consumption (REC) is crucial for the design and choice of policy packages. This study aims to empirically investigate the effect of environmental policy stringency index (EPS) and its components on REC in 27 OECD countries over the period from 1990 to 2015, and then use the results to identify what the appropriate environmental policy mix should look like. By relying on the two-step system GMM estimator, we provide evidence that increasing environmental policy stringency as a whole promotes renewable energy consumption in these 27 developed economies. Moreover, policymakers are able, through the market- and non-market-based environmental policy instruments, to increase the use of renewable energy. However, not all of these instruments are effective for achieving this goal. The results indicate that R&D subsidies and trading schemes have a positive and significant impact on REC, while taxes, feed-in tariff and emission standards have not a significant effect. Furthermore, R&D subsidies are more effective than trading schemes for stimulating the use of clean energy. These findings proved to be robust across the three alternative panel techniques used.

Keywords: environmental policy stringency, renewable energy consumption, two-step system-GMM estimation, linear dynamic panel data model

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12098 Effect of Chromium Yeast on Hematological Parameters in Camel Calves (Camelus dromedaries) Reared under Hot Summer Conditions

Authors: Khalid Ahmed Abdoun, Mohamed Abdulwahid Alsoufi, Ibrahim Abdullah Alhidary

Abstract:

The intention of this study was to evaluate the effect of dietary Cr supplementation on haematological parameters in camel calves reared under hot summer conditions. Fifteen male camel calves (5 – 6 months old) were randomly allotted to three dietary treatments (n = 5) for a period of 84 days. Camel calves were fed ad libitum on basal diet without Cr supplementation (control), basal diet supplemented with 0.5 mg Cr/kg DM (Cr 0.5) or basal diet supplemented with 1.0 mg Cr/kg DM (Cr 1.0). During this, blood samples were collected every four weeks for hematological examination. The obtained results revealed that dietary Cr supplementation to camel calves reared under hot summer did not show significant effects (P> 0.05) on hematological variables. However, the neutrophil to lymphocytes ratio (N: L ratio) was significantly (P < 0.05) reduced in camel calves fed on diets supplemented with chromium. In conclusion, Chromium supplementation to the diet of camel calves did not show any significant effects on hematological variables. Whereas, the neutrophil to lymphocytes ratio (N: L ratio) was reduced in camel calves fed diets supplemented with chromium.

Keywords: camel calves, chromium, haematological, immune response

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12097 Effect of Yttrium Doping on Properties of Bi2Sr1.9Ca0.1-xYxCu2O7+δ (Bi-2202) Cuprate Ceramics

Authors: Y. Boudjadja, A. Amira, A. Saoudel, A. Varilci, S. P. Altintas, C. Terzioglu

Abstract:

In this work, we report the effect of Y3+ doping on structural, mechanical and electrical properties of Bi-2202 phase. Samples of Bi2Sr1.9Ca0.1-xYxCu2O7+δ with x = 0, 0.025, 0.05, 0.075 and 0.1 are elaborated in air by conventional solid state reaction and characterized by X-Ray Diffraction (XRD), Scanning Electronic Microscopy (SEM) combined with EDS spectroscopy, density, Vickers micro-hardness and resistivity measurements. A good correlation between the variations of the bulk density and the Vickers micro-hardness with doping is obtained. The SEM photograph shows that the samples are composed of grains with a flat shape that characterizes the Bi-based cuprates. Quantitative EDS analysis confirms the reduction of Ca content and the increase of Y content when x is increased. The variation of resistivity with temperature shows that only samples with x = 0, 0.025 and 0.05 present an onset transition to the superconducting state. The higher onset transition temperature is obtained for x = 0.025 and is about 93.62 K. The transition is wide and is realized in two steps confirming then the presence of the low Tc Bi-2201 phase in the samples. For x = 0.075 and 0.1, a transition to a semiconducting state is seen at low temperatures. Some physical parameters are extracted from these curves and discussed.

Keywords: Bi-2202 phase, doping, structure, mechanical and electrical properties

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12096 Efficacy of Three Different Herbicides to the Control of Wild Barley (Hordeum spontaneum C. Koch) in Relation to Plant Growth Stage and Nitrogen Fertilizer Additive

Authors: Sh. Edrisi, M. Moeeni, A. Farahbakhsh

Abstract:

To study the effect of nitrogenous additive spray solution on the efficacy of three herbicides i.e. pinoxaden (Trade name: Axial), sulfosulfuron+metsulfuron-methyl (Trade name: Total) and sulfosulfuron (Trade name: Apirus) in controlling wild barley (Hordeum spontaneum C. Koch), in different growth stages, a greenhouse experiment as a split plot in a completely randomized design in three replications was conducted. One month after treatments, all plants were harvested and growth parameters were determined. The data were analyzed with computer. The results showed that the herbicide applications with and without nitrogen additive caused significant reductions in growth parameters of wild barley at 2-4 leaf stage. However, the plants were not killed by this herbicide. Plants were killed completely due to applications of the two other herbicides i.e. Apirus and Total at 2-4 leaf. There was no significant difference between the effect of these two herbicides. There was no significant difference between the highest rate of each herbicide used alone and that of the lowest rate with nitrogenous additive.

Keywords: growth stage, herbicide, nitrogen, wild barley

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12095 Effect of Recruitment and Selection on Employee Performance in Hospitality Industries

Authors: Yusuf A. Bako, Olubunmi O. Kolawole

Abstract:

This study sought to establish the effect of recruitment and selection on the employee performance in hospitality industries. The success of any organization in this modern business environment depends on the caliber of the manpower that steer the affairs of the organization. History has shown that recruitment and selection as a function of human resources management practices have a pivotal role in determining the level of employee performance in an organization. The hospitality industries have been faced with challenges of performance due to unconventional selection and placement practices in terms of poor policy in selecting candidate, inconsistency in selection process, sidetracking employment test and interview, godfatherism and regional selection process etc. The overall objective of the study was to determine how recruitment and selection affect employee performance in hospitality industry in Ogun State, Nigeria. This study adopts descriptive and inferential research design while population was drawn from leading hotels in Ogun State, Nigeria. The samples size was 100 employees and questionnaire was used to collect data while Cronbach alpha was used to test the instrument. The result of the study reveals that correlation between employee performance and recruitment and selection were highly significant.

Keywords: employee performance, human resources management, practices, recruitment, selection

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12094 Flow Control Optimisation Using Vortex Generators in Turbine Blade

Authors: J. Karthik, G. Vinayagamurthy

Abstract:

Aerodynamic flow control is achieved by interaction of flowing medium with corresponding structure so that its natural flow state is disturbed to delay the transition point. This paper explains the aerodynamic effect and optimized design of Vortex Generators on the turbine blade to achieve maximum flow control. The airfoil is chosen from NREL [National Renewable Energy Laboratory] S-series airfoil as they are characterized with good lift characteristics and lower noise. Vortex generators typically chosen are Ogival, Rectangular, Triangular and Tapered Fin shapes attached near leading edge. Vortex generators are typically distributed from the primary to tip of the blade section. The design wind speed is taken as 6m/s and the computational analysis is executed. The blade surface is simulated using k- ɛ SST model and results are compared with X-FOIL results. The computational results are validated using Wind Tunnel Testing of the blade corresponding to the design speed. The effect of Vortex generators on the flow characteristics is studied from the results of analysis. By comparing the computational and test results of all shapes of Vortex generators; the optimized design is achieved for effective flow control corresponding to the blade.

Keywords: flow control, vortex generators, design optimisation, CFD

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12093 Comparison of the Effect of Nano Calcium Carbonate and CaCO₃ on Egg Production, Egg Traits and Calcium Retention in Laying Japanese Quail

Authors: Farhad Ahmadi, Hamed Kimiaee, Fariba Rahimi

Abstract:

This research study focuses on the effect of different levels and sources of calcium on egg production, egg traits, and calcium retention in laying Japanese quail. The study aims to determine the impact of nano calcium carbonate (NCC) and calcium carbonate (CC) on these factors. The research was conducted using a total of 280 laying quail with an average age of 8 weeks. The quails were randomly distributed in a completely randomized design (CRD) with 7 treatments, 4 replications, and 10 quails in each pen. The study lasted for 90 days. The experimental diets included a control group (T1) with a basal diet consisting of 3.17% CaCO₃, and other groups supplemented with different levels (0.5%, 0.1%, and 0.15%) of either calcium carbonate (CC) or nano calcium carbonate (NCC). The quails had free access to water and feed throughout the study period. Findings: The results of the study showed that NCC at the levels of 0.1% and 0.15% (T6 and T7) improved eggshell thickness, shell thickness, and shell breaking strength compared to the control group. Although not statistically significant, there was an increasing trend in quail egg production and calcium retention in the calcareous shell of the egg in birds that consumed the experimental diets containing different levels of NCC compared to the control and other treatment groups. Quail egg production was recorded monthly for each treatment group. At the end of the study, a total of 40 eggs (10 eggs/replicate) from each treatment group were randomly selected for analysis. Parameters such as eggshell thickness, shell thickness, shell breaking strength, and calcium retention were measured. Statistical analysis was performed to compare the results between the different treatment groups. In conclusion, this study suggests that NCC at the levels of 0.1% and 0.15% can improve the quantity and quality of eggs and calcium retention in laying Japanese quail. These findings highlight the potential benefits of using NCC as a calcium source in quail diets. Further research could be conducted to explore the mechanisms behind these improvements and optimize the dosage of NCC for maximum effect.

Keywords: egg, calcium, nanoparticles, physiology

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12092 Thermo-Mechanical Analysis of Dissimilar Al/Cu Foil Single Lap Joints Made by Composite Metal Foil Manufacturing

Authors: Javaid Butt, Habtom Mebrahtu, Hassan Shirvani

Abstract:

The paper presents a new additive manufacturing process for the production of metal and composite parts. It is termed as composite metal foil manufacturing and is a combination of laminated object manufacturing and brazing techniques. The process has been described in detail and is being used to produce dissimilar aluminum to copper foil single lap joints. A three dimensional finite element model has been developed to study the thermo-mechanical characteristics of the dissimilar Al/Cu single lap joint. The effects of thermal stress and strain have been analyzed by carrying out transient thermal analysis on the heated plates used to join the two 0.1mm thin metal foils. Tensile test has been carried out on the foils before joining and after the single Al/Cu lap joints are made, they are subjected to tensile lap-shear test to analyze the effect of heat on the foils. The analyses are designed to assess the mechanical integrity of the foils after the brazing process and understand whether or not the heat treatment has an effect on the fracture modes of the produced specimens.

Keywords: brazing, laminated object manufacturing, tensile lap-shear test, thermo-mechanical analysis

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12091 Effect of High Dose of Vitamin C in Reduction Serum Uric Acid: a Comparative Study between Hyperuricemic and Gouty Patients in Jeddah

Authors: Firas S. Azzeh

Abstract:

Background: Vitamin C is a water soluble vitamin that is necessary for normal growth and development. Hyperuricemia is commonly detected in subjects with abnormal purine metabolism. Prolonged hyperuricemia is an important risk factor for damaged joint and often associated with gout. Objectives: To compare the effect of high dose of vitamin C supplements on uric acid treatment between hyperuricemic and gouty patients in Jeddah, Saudi Arabia, as well as finding out the effect of vitamin C on serum creatinine level and glomerular filtration rate (GFR). Subjects and Methods: This comparative study started on April 2013 and lasted tells March 2014. A convenience sample of 30 adults was recruited in this study from Doctor Abdulrahman Taha Bakhsh Hospital in Jeddah (Saudi Arabia). Eligible persons were assigned into two study groups; hyperuricemic (n=15) and gouty (n=15) groups. Subjects have been accepted for participating in the study after completing the consent form. Each participant consumed 500 mg/day vitamin C chew able tablets. All participants have been followed-up for 2 months. Twelve hours fasting blood samples have been collected 3 times from each participant during the study period; at the beginning before and retested after each month of the study period. Uric acid, serum creatinine and GFR were measured. Results: For gouty group, uric acid increased insignificantly after 2 months by about +0.3 mg/dl. On the other hand, hyperuricemic group showed decrease (P ≤ 0.05) in uric acid after 2 months of study period by about -0.78 mg/dl. Serum creatinine level insignificantly decreased for all participants during the study period, which leaded to insignificant increase in GFR for all participants. Conclusion: Supplementation with 500 mg/day vitamin C for 2 months significantly reduced serum uric acid for hyperuricemic patients and insignificantly increased serum uric acid for gouty patients. The ineffectiveness of vitamin C supplements on patients with established gout could be related to a number of potential reasons.

Keywords: vitamin c, Hyperuricemia, gout, creatinine, GFR

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12090 Corporate Social Responsibility (CSR) and Energy Efficiency: Empirical Evidence from the Manufacturing Sector of India

Authors: Baikunthanath Sahoo, Santosh Kumar Sahu, Krishna Malakar

Abstract:

With the essence of global environmental sustainability and green business management, the wind of business research moved towards Corporate Social Responsibility. In addition to international and national treaties, businesses have also started realising environmental protection and energy efficiency through CSR as part of business strategy in response to climate change. Considering the ambitious emission reduction target and rapid economic development of India, this study is an attempt to explore the effect of CSR on the energy efficiency management of manufacturing firms in India. By using firm-level data, the panel fixed effect model shows that the CSR dummy variable is negatively influencing the energy intensity or technically, they are energy efficient. The result demonstrates that in the presence of CSR, all the production economic variables are significant. The result also shows that doing environmental expenditure does not improve energy efficiency might be because very few firms are motivated to do such expenditure and also not common to all sectors. The interactive effect model result conforms that without considering CSR dummy as an intervening variable only Manufacturers of Chemical and Chemical products, Manufacturers of Pharmaceutical, medical chemical, and botanical products firms energy intensity low but after considering CSR in their business practices all six sub-sector firms become energy efficient. The empirical result also validate that firms are continuously engaged in CSR activities they are highly energy efficient. It is an important motivational factor for firms to become economically and environmentally sustainable in the corporate world. This analysis would help business practitioners to know how to manage today’s profitability and tomorrow’s sustainability to achieve a comparative advantage in the emerging market economy. The paper concludes that reducing energy consumption as part of their social responsibility to care for the environment, will need collaborative efforts of business society and policy bodies.

Keywords: CSR, Energy Efficiency, Indian manufacturing Sector, Business strategy

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12089 The Effect of Benson Relaxation Method on Quality of Life in Hemodialysis Patients in 2012-2013, Kermanshah, Iran

Authors: Fateme Hadadian, Behnam Khaledi Paveh, Hosein Feizi

Abstract:

Background: High number of patients with end-stage renal disease worldwide, and Iran and the patients required hemodialysis, As well as symptoms and treatment process and its impact on quality of life The researcher had to take a step towards solving these problems. Methods: In randomized clinical trial in 60 hemodialysis patients admitted to hospital hemodialysis Imam Reza (AS) were studied. Using questionnaires dialysis patients' QOL, quality of life was measured in patients and controls were divided randomly into two groups. Benson's relaxation method for the experimental group and two months at home, once per day, respectively and the control group received no special action. Immediately after the end of the period with was used for evaluating the quality of life in both the experimental and control groups were survey and data using independent t-test were used for statistical analysis. Results: The general dimensions of quality of life scores before and after intervention, there was significant difference (P=0/001). But this difference was not significant after QOL (P=0/2). Between QOL scores before and after treatment between the two groups was statistically significant (P=0/02). Conclusion: Benson relaxation has the desired effect on quality of life in hemodialysis patients and can be used as a useful method to enhance the quality of life in hemodialysis patients, implementation and training will be given.

Keywords: hemodialysis, quality of life, Benson muscle relaxation, biomedicine

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12088 Relative Study of the Effect of the Temperature Gradient on Free Vibrations of Clamped Visco-Elastic Rectangular Plates with Linearly and Exponentially Thickness Variations Respectively in Two Directions

Authors: Harvinder Kaur

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Rayleigh–Ritz method is a broadly used classical method for the calculation of the natural vibration frequency of a structure in the second or higher order. Here it is used to construct a mathematical model of relative study of the thermal effect on free transverse vibrations of clamped (c-c-c-c type) visco-elastic rectangular plate with linearly and exponentially thickness variations respectively in two directions. Researchers in the field of Engineering always make an effort for better designs of mechanical structures. In-depth study of the vibration behavior of tapered plates with diverse thickness variation under high temperature would ultimately help to finalize the accurate design of a structure. The perfect tapered structure saves weight and as well as expenses. In the present paper, the comparison has been done for deflection and time period corresponding to the first two modes of vibrations of clamped plate for various values of aspect ratio, thermal constants, and taper constants of both the cases.

Keywords: Rayleigh-Ritz Method, tapered plates, transverse vibration, thermal constant, visco-elasticity

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12087 Effect of Madecassoside on the Antioxidant Status of Streptozotocin-Nicotinamide Induced Diabetes in Sprague-Dawley Rats

Authors: C. Mayuren, C. K. Paul Wang, K. Purushotham, C. Dinesh Kumar

Abstract:

Diabetes Mellitus (DM) is one of the most common non-communicable diseases globally. Although significant advances have led to better understanding of the condition and the development of effective therapies and preventive strategies, the pathway to cure remains elusive and DM prevails as a serious medical challenge in the 21st century. Oxidative stress has been suggested to contribute to the progression and pathophysiological conditions of diabetes. Madecassoside (MA) a major pentacyclic triterpenoid, has been demonstrated to possess various biological activities. However, no attempt has been made to study the antioxidant activity in diabetic rats. Therefore, the present study is aimed to evaluate the antioxidant effect of MA on streptozotocin-nicotinamide induced type-2 diabetes in Sprague-Dawley rats. The study protocol was approved by the institutional ethical committee prior to the conduct of research. Adult male Sprague-Dawley rats weighing 250-300 g were used in the study. The animals were rendered diabetic with a single intraperitoneal dose of streptozotocin (65 mg/kg) and nicotinamide (110 mg/kg). The diabetic animals after a stabilisation period of 14 days received various treatments (Madecassoside 50 mg/kg; Glimepiride 2.5 mg/kg) suspended in 0.5% carboxymethyl cellulose orally, for a period of 28 days. The animals fasted overnight after the last treatment were sacrificed and the pancreas, liver and kidneys were isolated. The weighted quantity of the samples of various treatments were homogenised in ice-cold condition and were subjected to lipid peroxidation, catalase and superoxide dismutase assay. The data’s obtained were subjected to statistical analysis. Diabetic rats showed significant increase in lipid peroxidation and decrease in enzymatic antioxidant levels. All the treated groups had significantly higher SOD, CAT and reduced LPO activity in the pancreas, liver and kidney. Results suggest madecassoside to have potential antioxidant effect against the diabetic model. However further investigations are necessary to study the mechanism at the cellular level.

Keywords: antioxidant, diabetes, madecassoside, nicotinamide, streptozotocin

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12086 Effect of Pollination on Qualitative Characters of Rapeseed (Brassica campestris l. Var. Toria) Seed in Chitwan, Nepal

Authors: Rameshwor Pudasaini

Abstract:

An experiment was conducted to study the effect of pollination quality of rapeseed seed in Chitwan during 2012-2013. The experiment was designed in Randomized Complete Block with four replications and five pollination treatments. The rapeseed plots were caged with mosquito nets at 10% flowering except natural pollination. Two-framed colonies of Apis mellifera L. and Apis cerana F. were introduced separately for pollination, and control plot caged without pollinators. The highest germination percent was observed on Apis cerana F. pollinated plot seeds (90.50% germination) and lowest on control plots (42.00% germination) seeds. Similarly, seed test weight of Apis cerana F. pollinated plots (3.22 gm/ 1000 seed) and Apis mellifera L. pollinated plots (2.93 gm/1000 seed) were and control plots (2.26 gm/ 1000 seed) recorded respectively. However, oil content was recorded highest on pollinated by Apis cerana F. (36.1 %) and lowest on control plots (32.8%). This study clearly indicated pollination increases the seed quality of rapeseed and therefore, management of honeybee is necessary for higher quality of rapeseed under Chitwan condition.

Keywords: apis cerana, apis mellifera, rapeseed pollination, rapeseed quality

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12085 Antifungal Protein ~35kDa Produced by Bacillus cereus Inhibits the Growth of Some Molds and Yeasts

Authors: Saleh H. Salmen, Sulaiman Ali Alharbi, Hany M. Yehia, Mohammad A. Khiyami, Milton Wainwright, Naiyf S. Alharbi, Arunachalam Chinnathambi

Abstract:

An antifungal protein synthesized by Bacillus cereus has been partially purified by the use of ammonium sulfate precipitation and Sephadex-G-200 column chromatography. The protein was produced from Bacillus cereus grown in potato Dextrose Broth Medium (PDB) at 30 ºC for 3 days at 100 rpm. The protein showed antagonistic effect against some fungi and yeasts. Crude extract from medium and semi-purified protein were tested in vitro against both fungi and yeasts using the disc diffusion method in order to detect the inhibitory effect of the protein. Zones of inhibition of the following diameter were found (mm) were Alternaria alternate (28), Rhodotorula glutinis (20), Fusarium sp. (16), Rhizopus sp. (15), Penicillium digitatum (13), Mucor sp. (13) and Aspergillus niger (10). The isolated protein was found to have a molecular weight of ~35kDa by sodium deodecyl sulfate-poly acrylamide gel electrophoresis. The data showed that the protein of Bacillus cereus has antifungal activity, a fact which points to the possibility of using it as a bio-control agent against some fungi, findings which emphasize the potential role of B. cereus as an important bio-control agent.

Keywords: bacillus cereus, ~35kDa protein, molds, yeasts

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12084 Assessing the Pre-Service and In-Service Teachers’ Continuation of Use of Technology After Participation in Professional Development

Authors: Ayoub Kafyulilo, Petra Fisser, Joke Voogt

Abstract:

This study was conducted to assess the continuation of the use of technology in science and mathematics teaching of the pre-service and in-service teachers who attended the professional development programme. It also assessed professional development, personal, institutional, and technological factors contributing to the continuous use of technology in teaching. The study involved 42 teachers, thirteen pre-service teachers, and twenty-nine in-service teachers. A mixed-method research approach was used to collect data for this study. Findings showed that the continuous use of technology in teaching after the termination of the professional development arrangement was high among the pre-service teachers, and differed for the in-service teachers. The regression model showed that knowledge and skills, access to technology and ease of use were strong predictors (R2 = 55.3%) of the teachers’ continuous use of technology after the professional development arrangement. The professional development factor did not have a direct effect on the continuous use of technology, rather had an influence on personal factors (knowledge and skills). In turn, the personal factors had influence on the institutional factors (access to technology) and technological factors (ease of use), which together had an effect on the teachers’ continuous use of technology in teaching.

Keywords: technology, professional development, teachers, science and mathematics

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12083 Preparation Nanocapsules of Chitosan Modified With Selenium Extracted From the Lactobacillus Acidophilus and Their Anticancer Properties

Authors: Akbar Esmaeili, Mahnoosh Aliahmadi

Abstract:

This study synthesized a modified imaging of gallium@deferoxamine/folic acid/chitosan/polyaniline/polyvinyl alcohol (Ga@DFA/FA/CS/PANI/PVA). It contains Morus nigra extract by selenium nanoparticles prepared from Lactobacillus acidophilus. Using the impregnation method, Se nanoparticles were then deposited on (Ga@DFA/FA/ CS/PANI/PVA). The modified contrast agents were mixed with M. nigra extract, and investigated their antibacterial activities by applying to L929 cell lines. The influence of variable factors, including 1. surfactant, 2. solvent, 3. aqueous phase, 4. pH, 5. buffer, 6. minimum Inhibitory concentration (MIC), 7. minimum bactericidal concentration (MBC), 8. cytotoxicity on cancer cells., 9. antibiotic, 10. antibiogram, 11. release and loading, 12. the emotional effect, 13. the concentration of nanoparticles, 14. olive oil, and 15. they have investigated thermotical methods. The structure and morphology of the synthesized contrast agents were characterized by zeta potential sizer analysis (ZPS), X-Ray diffraction (XRD), Fourier-transform infrared (FT-IR), energy dispersive X-ray (EDX), ultraviolet–visible (UV–Vis) spectra, and scanning electron microscope (SEM). The experimental section was conducted and monitored by response surface methods (RSM), MTT, MIC, MBC, and cancer cytotoxic conversion assay. Antibiogram testing of NCs on Pseudomonas aeruginosa bacteria was successful and obtained MIC = 2 factors with less harmful effect. All experimental sections confirmed that our synthesized particles have potent antioxidant properties. Antibiogram testing revealed that NPS could kill P. aeruginosa and P. aeruginosa. A variety of synthetic conditions were done by diffusion emulsion method by varying parameters, the optimum state of DFA release Ga@DFA/FA/CS/PANI/PVA NPs (6 ml) with pH = 5.5, time = 3 h, NCs and DFA (3 mg), and achieved buffer (20 ml). DFA in Ga@DFA/FA/ CS/PANI/PVA was released and showed an absorption peak at 378 nm by applying a 300-rpm magnetic rate. In this report, Ga decreased the harmful effect on the human body.

Keywords: nanocapsules, technolgy, biology, nano

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12082 Effect of Using Different Packaging Materials on Quality of Minimally Process (Fresh-Cut) Banana (Musa acuminata balbisiana) Cultivar 'Nipah'

Authors: Nur Allisha Othman, Rosnah Shamsudin, Zaulia Othman, Siti Hajar Othman

Abstract:

Mitigating short storage life of fruit like banana uses minimally process or known as fresh cut can contribute to the growing demand especially in South East Asian countries. The effect of different types of packaging material on fresh-cut Nipah (Musa acuminata balbisiana) were studied. Fresh cut banana cultivar (cv) Nipah are packed in polypropylene plastic (PP), low density polypropylene plastic (LDPE), polymer plastic film (shrink wrap) and polypropylene container as control for 12 days at low temperature (4ᵒC). Quality of physical and chemical evaluation such as colour, texture, pH, TA, TSS, and vitamin C were examined every 2 days interval for 12 days at 4ᵒC. Result shows that the PP is the most suitable packaging for banana cv Nipah because it can reduce respiration and physicochemical quality changes of banana cv Nipah. Different types of packaging significantly affected quality of fresh-cut banana cv Nipah. PP bag was the most suitable packaging to maintain quality and prolong storage life of fresh-cut banana cv Nipah for 12 days at 4ᵒC.

Keywords: physicochemical, PP, LDPE, shrink wrap, browning, respiration

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12081 Effect of Bentonite on the Rheological Behavior of Cement Grout in Presence of Superplasticizer

Authors: K. Benyounes, A. Benmounah

Abstract:

Cement-based grouts has been used successfully to repair cracks in many concrete structures such as bridges, tunnels, buildings and to consolidate soils or rock foundations. In the present study, the rheological characterization of cement grout with water/binder ratio (W/B) is fixed at 0.5. The effect of the replacement of cement by bentonite (2 to 10 % wt) in presence of superplasticizer (0.5 % wt) was investigated. Several rheological tests were carried out by using controlled-stress rheometer equipped with vane geometry in temperature of 20°C. To highlight the influence of bentonite and superplasticizer on the rheological behavior of grout cement, various flow tests in a range of shear rate from 0 to 200 s-1 were observed. Cement grout showed a non-Newtonian viscosity behavior at all concentrations of bentonite. Three parameter model Herschel-Bulkley was chosen for fitting of experimental data. Based on the values of correlation coefficients of the estimated parameters, The Herschel-Bulkley law model well described the rheological behavior of the grouts. Test results showed that the dosage of bentonite increases the viscosity and yield stress of the system and introduces more thixotropy. While the addition of both bentonite and superplasticizer with cement grout improve significantly the fluidity and reduced the yield stress due to the action of dispersion of SP.

Keywords: rheology, cement grout, bentonite, superplasticizer, viscosity, yield stress

Procedia PDF Downloads 362
12080 A Ferutinin Analogue with Enhanced Potency and Selectivity against Estrogen Receptor Positive Breast Cancer Cells in vitro

Authors: Remi Safi, Aline Hamade, Najat Bteich, Jamal El Saghir, Mona Diab Assaf, Marwan El-Sabban, Fadia Najjar

Abstract:

Estrogen is considered a risk factor for breast cancer since it promotes breast-cell proliferation. The jaesckeanadiol-3-p-hydroxyphenylpropanoate, a hemi-synthetic analogue of the natural phytoestrogen ferutinin (jaesckeanadiol-p-hydroxybenzoate), is designed to be devoid of estrogenic activity. This analogue induces a cytotoxic effect 30 times higher than that of ferutinin towards MCF-7 breast cancer cell line. We compared these two compounds with respect to their effect on proliferation, cell cycle distribution and cancer stem-like cells in the MCF-7 cell line. Treatment with ferutinin (30 μM) and its analogue (1 μM) produced a significant accumulation of cells at the pre G0/G1 cell cycle phase and triggered apoptosis. Importantly, this compound retains its anti-proliferative activity against breast cancer stem/progenitor cells that are naturally insensitive to ferutinin at the same dose. These results position ferutinin analogue as an effective compound inhibiting the proliferation of estrogen-dependent breast cancer cells and consistently targeting their stem-like cells.

Keywords: ferutinin, hemi-synthetic analogue, breast cancer, estrogen, stem/progenitor cells

Procedia PDF Downloads 189