Search results for: multidrug resistance protein 3
5025 Comparison of Physicochemical Properties of Catfish Myofibrillar and Sarcoplasmic Protein Hydrolysates and Characterization of Their Bioactive Peptides
Authors: Leila Najafian
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Sarcoplasmic protein hydrolysates (SPHs) and myofibrillar protein hydrolysates (MPHs) from patin (Pangasius sutchi) were produced using two types of proteases: Papain and Alcalase. 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical scavenging activities and metal chelating activity assays for antioxidant activities were carried out on the SPHs and MPHs. The hydrolysates were isolated and purified by ultrafiltration, gel filtration and reverse phase high-performance liquid chromatography (RP-HPLC) and liquid chromatography with tandem mass spectrometry detection (LC-MS/MS) was used in identifying peptide sequences. The results showed that when the DH of MPHs increased, the protein solubility increased, while the highest amount of the protein solubility of SPHs was after 60 min incubation. The effect of DH on antioxidant activities of SPHs and MPHs was investigated. Among the hydrolysates, papain-MPH and Alcalase-SPH, which had the highest antioxidant activities, were purified. The potent fractions obtained from RP-HPLC of sarcoplasmic (SI 3 fraction) and myofibrillar (MI 4 fraction) hydrolysates showed the highest DPPH radical scavenging activity. The FVNQPYLLYSVHMK peptide for MPH and the LVVDIPAALQHA peptide for SPH exhibited the highest antioxidant activity. The presence of hydrophobic and hydrophilic amino acids, namely leucine (L), valine (V), phenylalanine (F), histidine (H) and proline (P), in the peptide sequences of SPH and MPH are believed to contribute to high antioxidant activity. Hence, SPH and MPH from patin have the potential as a natural functional ingredient in food and pharmaceutical industry.Keywords: patin (Pangasius sutchi), protein hydrolysates, antioxidative peptides, mass spectrometry
Procedia PDF Downloads 2605024 Tamper Resistance Evaluation Tests with Noise Resources
Authors: Masaya Yoshikawa, Toshiya Asai, Ryoma Matsuhisa, Yusuke Nozaki, Kensaku Asahi
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Recently, side-channel attacks, which estimate secret keys using side-channel information such as power consumption and compromising emanations of cryptography circuits embedded in hardware, have become a serious problem. In particular, electromagnetic analysis attacks against cryptographic circuits between information processing and electromagnetic fields, which are related to secret keys in cryptography circuits, are the most threatening side-channel attacks. Therefore, it is important to evaluate tamper resistance against electromagnetic analysis attacks for cryptography circuits. The present study performs basic examination of the tamper resistance of cryptography circuits using electromagnetic analysis attacks with noise resources.Keywords: tamper resistance, cryptographic circuit, hardware security evaluation, noise resources
Procedia PDF Downloads 5045023 A Comparative Study of the Physicochemical and Structural Properties of Quinoa Protein Isolate and Yellow Squat Shrimp Byproduct Protein Isolate through pH-Shifting Modification
Authors: María José Bugueño, Natalia Jaime, Cristian Castro, Diego Naranjo, Guido Trautmann, Mario Pérez-Won, Vilbett Briones-Labarca
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Proteins play a crucial role in various prepared foods, including dairy products, drinks, emulsions, and ready meals. These food proteins are naturally present in food waste and byproducts. The alkaline extraction and acid precipitation method is commonly used to extract proteins from plants and animals due to its product stability, cost-effectiveness, and ease of use. This study aimed to investigate the impact of pH-shifting storage at two different pH levels on the conformational changes affecting the physicochemical and functional properties of quinoa protein isolate (QPI) and yellow shrimp byproduct protein isolate (YSPI). The QPI and YSPI were extracted using the alkaline extraction-isoelectric precipitation method. The dispersions were adjusted to pH 4 or 12, stirred for 2 hours at 20°C to achieve a uniform dispersion, and then freeze-dried. Various analyses were conducted, including flexibility (F), free sulfhydryl content (Ho), emulsifying activity (EA), emulsifying capacity (EC), water holding capacity (WHC), oil holding capacity (OHC), intrinsic fluorescence, ultraviolet spectroscopy, differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR) to assess the properties of the protein isolates. pH-shifting at pH 11 and 12 for QPI and YSPI, respectively, significantly improved protein properties, while property modification of the samples treated under acidic conditions was less pronounced. Additionally, the pH 11 and 12 treatments significantly improved F, Ho, EA, WHC, OHC, intrinsic fluorescence, ultraviolet spectroscopy, DSC, and FTIR. The increase in Ho was due to disulfide bond disruption, which produced more protein sub-units than other treatments for both proteins. This study provides theoretical support for comprehensively elucidating the functional properties of protein isolates, promoting the application of plant proteins and marine byproducts. The pH-shifting process effectively improves the emulsifying property and stability of QPI and YSPI, which can be considered potential plant-based or marine byproduct-based emulsifiers for use in the food industry.Keywords: quinoa protein, yellow shrimp by-product protein, physicochemical properties, structural properties
Procedia PDF Downloads 435022 The Role of Il-6-Mediated NS5ATP9 Expression in Autophagy of Liver Cancer Cells
Authors: Hongping Lu, Kelbinur Tursun, Yaru Li, Yu Zhang, Shunai Liu, Ming Han
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Objective: To investigate whether NS5ATP9 is involved in IL-6 mediated autophagy and the relationship between IL-6 and NS5ATP9 in liver cancer cells. Methods: 1. Detect the mRNA and protein levels of Beclin 1 after HepG2 cells were treated with or without recombinant human IL-6 protein. 2. Measure and compare of the changes of autophagy-related genes with their respective control, after IL-6 was silenced or neutralized with monoclonal antibody against human IL-6. 3. HepG2 cells were incubated with 50 ng/ml of IL-6 in the presence or absence of PDTC. The expression of NS5ATP9 was analyzed by Western blot after 48 h. 4. After NS5ATP9-silenced HepG2 cells had been treated with 50 ng/ml recombinant IL-6 protein, we detected the Beclin 1 and LC3B (LC3Ⅱ/Ⅰ) expression. 5. HepG2 cells were transfected with pNS5ATP9, si-NS5ATP9, and their respective control. Total RNA was isolated from cells and analyzed for IL-6. 6. Silence or neutralization of IL-6 in HepG2 cells which has been transfected with NS5ATP9. Beclin 1 and LC3 protein levels were analyzed by Western blot. Result: 1. After HepG2 were treated with recombinant human IL-6 protein, the expression of endogenous Beclin 1 was up-regulated at mRNA and protein level, and the conversion of endogenous LC3-I to LC3-II was also increased. These results indicated that IL-6 could induce autophagy. 2. When HepG2 cells were treated with IL-6 siRNA or monoclonal antibody against human IL-6, the expression of autophagy-related genes were decreased. 3. Exogenous human IL-6 recombinant protein up-regulated NS5ATP9 via NF-κB activation. 4. The expression of Beclin 1 and LC3B was down-regulated after IL-6 treated NS5ATP9-silenced HepG2 cells. 5. NS5ATP9 could reverse regulates IL-6 expression in HepG2 cells. 6. Silence or neutralization of IL-6 attenuates NS5ATP9-induced autophagy slightly. Conclusion: Our results implied that in HCC patients, maybe the higher level of IL-6 in the serum promoted the expression of NS5ATP9 and induced autophagy in cancer cells. And the over-expression of NS5ATP9 which induced by IL-6, in turn, increased IL-6 expression, further, promotes the IL-6/NS5ATP9-mediated autophagy and affects the progression of tumor. Therefore, NS5ATP9 silence might be a potential target for HCC therapy.Keywords: autophagy, Hepatocellular carcinoma, IL-6, microenvironment, NS5ATP9
Procedia PDF Downloads 2505021 Investigation of Textile Laminates Structure and Electrical Resistance
Authors: A. Gulbiniene, V. Jankauskaite
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Textile laminates with breathable membranes are used extensively in protective footwear. Such polymeric membranes act as a barrier to liquid water and soil entry from the environment, but are sufficiently permeable to water vapour to allow significant amounts of sweat to evaporate and affect the comfort of the wearer. In this paper the influence of absorbed humidity amount on the electrical properties of textiles lining laminates with and without polymeric membrane is presented. It was shown that textile laminate structure and its layers have a great influence on the water vapour absorption. Laminates with polyurethane foam layers show lower ability to absorb water vapour. Semi-permeable membrane increases absorbed humidity amount. The increase of water vapour absorption ability decreases textile laminates' electrical resistance. However, the intensity of the decrease in electrical resistance depends on the textile laminate layers' nature. Laminates with polyamide layers show significantly lower electrical resistance values.Keywords: electrical resistance, humid atmosphere, textiles laminate, water vapour absorption
Procedia PDF Downloads 2425020 Cellular Degradation Activity is Activated by Ambient Temperature Reduction in an Annual Fish (Nothobranchius rachovii)
Authors: Cheng-Yen Lu, Chin-Yuan Hsu
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Ambient temperature reduction (ATR) can extend the lifespan of an annual fish (Nothobranchius rachovii), but the underlying mechanism is unknown. In this study, the expression, concentration, and activity of cellular-degraded molecules were evaluated in the muscle of N. rachovii reared under high (30 °C), moderate (25 °C), and low (20 °C) ambient temperatures by biochemical techniques. The results showed that (i) the activity of the 20S proteasome, the expression of microtubule-associated protein 1 light chain 3-II (LC3-II), the expression of lysosome-associated membrane protein type 2a (Lamp 2a), and lysosome activity increased with ATR; (ii) the expression of the 70 kD heat shock cognate protein (Hsc 70) decreased with ATR; (iii) the expression of the 20S proteasome, the expression of lysosome-associated membrane protein type 1 (Lamp 1), the expression of molecular target of rapamycin (mTOR), the expression of phosphorylated mTOR (p-mTOR), and the p-mTOR/mTOR ratio did not change with ATR. These findings indicated that ATR activated the activity of proteasome, macroautophagy, and chaperone-mediated autophagy. Taken together these data reveal that ATR likely activates cellular degradation activity to extend the lifespan of N. rachovii.Keywords: ambient temperature reduction, autophagy, degradation activity, lifespan, proteasome
Procedia PDF Downloads 4595019 Re-Engineering of Traditional Indian Wadi into Ready-to-Use High Protein Quality and Fibre Rich Chunk
Authors: Radhika Jain, Sangeeta Goomer
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In the present study an attempt has been made to re-engineer traditional wadi into wholesome ready-to-use cereal-pulse-based chunks rich in protein quality and fibre content. Chunks were made using extrusion-dehydration combination. Two formulations i.e., whole green gram dhal with instant oats and washed green gram dhal with whole oats were formulated. These chunks are versatile in nature as they can be easily incorporated in day-to-day home-made preparations such as pulao, potato curry and kadhi. Cereal-pulse ratio was calculated using NDpCal%. Limiting amino acids such as lysine, tryptophan, methionine, cysteine and threonine were calculated for maximum amino acid profile in cereal-pulse combination. Time-temperature combination for extrusion at 130oC and dehydration at 65oC for 7 hours and 15 minutes were standardized to obtain maximum protein and fibre content. Proximate analysis such as moisture, fat and ash content were analyzed. Protein content of formulation was 62.10% and 68.50% respectively. Fibre content of formulations was 2.99% and 2.45%, respectively. Using a 5-point hedonic scale, consumer preference trials of 102 consumers were conducted and analyzed. Evaluation of chunks prepared in potato curry, kadi and pulao showed preferences for colour 82%, 87%, 86%, texture and consistency 80%, 81%, 88%, flavour and aroma 74%, 82%, 86%, after taste 70%, 75%, 86% and overall acceptability 77%, 75%, 88% respectively. High temperature inactivates antinutritional compounds such as trypsin inhibitors, lectins, saponins etc. Hence, availability of protein content was increased. Developed products were palatable and easy to prepare.Keywords: extrusion, NDpCal%, protein quality, wadi
Procedia PDF Downloads 2245018 Effect of Resistance Training on Muscle Strength, IGF₁, and Physical Performance of Volleyball Players
Authors: Menan M. Elsayed, Hussein A. Heshmat
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The aim of the study is to assess the effect of resistance training on muscle strength and physical performance of volleyball players of Physical Education College, Helwan University. The researcher used the experimental method of pre-post measurements of one group of 10 volleyball players. The execution of the program was through the period of 12/8/2018 to 12/10/2018; included 24 training units, 3 training units weekly for 8 weeks. The training program revealed an improvement in post measurement of muscle strength, IGF₁ (insulin-like growth factor 1), and physical performance of players. It may be concluded that the resistance training may include changes in hormones and muscle fibers leading to hypertrophy of the muscle and physical performance. It is recommended to use the results of the study in rationing the loads and training programs.Keywords: IGF₁, muscle strength, physical performance, resistance training, volleyball players
Procedia PDF Downloads 1935017 A Comparison of Antibiotic Resistant Enterobacteriaceae: Diabetic versus Non-Diabetic Infections
Authors: Zainab Dashti, Leila Vali
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Background: The Middle East, in particular Kuwait, contains one of the highest rates of patients with Diabetes in the world. Generally, infections resistant to antibiotics among the diabetic population has been shown to be on the rise. This is the first study in Kuwait to compare the antibiotic resistance profiles and genotypic differences between the resistant isolates of Enterobacteriaceae obtained from diabetic and non-diabetic patients. Material/Methods: In total, 65 isolates were collected from diabetic patients consisting of 34 E. coli, 15 K. pneumoniae and 16 other Enterobacteriaceae species (including Salmonella spp. Serratia spp and Proteus spp.). In our control group, a total of 49 isolates consisting of 37 E. coli, 7 K. pneumoniae and 5 other species (including Salmonella spp. Serratia spp and Proteus spp.) were included. Isolates were identified at the species level and antibiotic resistance profiles, including Colistin, were determined using initially the Vitek system followed by double dilution MIC and E-test assays. Multi drug resistance (MDR) was defined as isolates resistant to a minimum of three antibiotics from three different classes. PCR was performed to detect ESBL genes (blaCTX-M, blaTEM & blaSHV), flouroquinolone resistance genes (qnrA, qnrB, qnrS & aac(6’)-lb-cr) and carbapenem resistance genes (blaOXA, blaVIM, blaGIM, blaKPC, blaIMP, & blaNDM) in both groups. Pulse field gel electrophoresis (PFGE) was performed to compare clonal relatedness of both E. coli and K.pneumonaie isolates. Results: Colistin resistance was determined in three isolates with MICs of 32-128 mg/L. A significant difference in resistance to ampicillin (Diabetes 93.8% vs control 72.5%, P value <0.002), augmentin (80% vs 52.5%, p value < 0.003), cefuroxime (69.2% vs 45%, p value < 0.0014), ceftazadime (73.8% vs 42.5%, p value <0.001) and ciprofloxacin (67.6% vs 40%, p value < 0.005) were determined. Also, a significant difference in MDR rates between the two groups (Diabetes 76.9%, control 57.5%, p value <0.036 were found. All antibiotic resistance genes showed a higher prevalence among the diabetic group, except for blaCTX-M, which was higher among the control group. PFGE showed a high rate of diversity between each group of isolates. Conclusions: Our results suggested an alarming rate of antibiotic resistance, in particular Colistin resistance (1.8%) among K. pneumoniea isolated from diabetic patients in Kuwait. MDR among Enterobacteriaceae infections also seems to be a worrying issue among the diabetics of Kuwait. More efforts are required to limit the issue of antibiotic resistance in Kuwait, especially among patients with diabetes mellitus.Keywords: antibiotic resistance, diabetes, enterobacreriacae, multi antibiotic resistance
Procedia PDF Downloads 3645016 Development of a Robust Protein Classifier to Predict EMT Status of Cervical Squamous Cell Carcinoma and Endocervical Adenocarcinoma (CESC) Tumors
Authors: ZhenlinJu, Christopher P. Vellano, RehanAkbani, Yiling Lu, Gordon B. Mills
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The epithelial–mesenchymal transition (EMT) is a process by which epithelial cells acquire mesenchymal characteristics, such as profound disruption of cell-cell junctions, loss of apical-basolateral polarity, and extensive reorganization of the actin cytoskeleton to induce cell motility and invasion. A hallmark of EMT is its capacity to promote metastasis, which is due in part to activation of several transcription factors and subsequent downregulation of E-cadherin. Unfortunately, current approaches have yet to uncover robust protein marker sets that can classify tumors as possessing strong EMT signatures. In this study, we utilize reverse phase protein array (RPPA) data and consensus clustering methods to successfully classify a subset of cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) tumors into an EMT protein signaling group (EMT group). The overall survival (OS) of patients in the EMT group is significantly worse than those in the other Hormone and PI3K/AKT signaling groups. In addition to a shrinkage and selection method for linear regression (LASSO), we applied training/test set and Monte Carlo resampling approaches to identify a set of protein markers that predicts the EMT status of CESC tumors. We fit a logistic model to these protein markers and developed a classifier, which was fixed in the training set and validated in the testing set. The classifier robustly predicted the EMT status of the testing set with an area under the curve (AUC) of 0.975 by Receiver Operating Characteristic (ROC) analysis. This method not only identifies a core set of proteins underlying an EMT signature in cervical cancer patients, but also provides a tool to examine protein predictors that drive molecular subtypes in other diseases.Keywords: consensus clustering, TCGA CESC, Silhouette, Monte Carlo LASSO
Procedia PDF Downloads 4685015 Detection of Alzheimer's Protein on Nano Designed Polymer Surfaces in Water and Artificial Saliva
Authors: Sevde Altuntas, Fatih Buyukserin
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Alzheimer’s disease is responsible for irreversible neural damage of brain parts. One of the disease markers is Amyloid-β 1-42 protein that accumulates in the brain in the form plaques. The basic problem for detection of the protein is the low amount of protein that cannot be detected properly in body liquids such as blood, saliva or urine. To solve this problem, tests like ELISA or PCR are proposed which are expensive, require specialized personnel and can contain complex protocols. Therefore, Surface-enhanced Raman Spectroscopy (SERS) a good candidate for detection of Amyloid-β 1-42 protein. Because the spectroscopic technique can potentially allow even single molecule detection from liquid and solid surfaces. Besides SERS signal can be improved by using nanopattern surface and also is specific to molecules. In this context, our study proposes to fabricate diagnostic test models that utilize Au-coated nanopatterned polycarbonate (PC) surfaces modified with Thioflavin - T to detect low concentrations of Amyloid-β 1-42 protein in water and artificial saliva medium by the enhancement of protein SERS signal. The nanopatterned PC surface that was used to enhance SERS signal was fabricated by using Anodic Alumina Membranes (AAM) as a template. It is possible to produce AAMs with different column structures and varying thicknesses depending on voltage and anodization time. After fabrication process, the pore diameter of AAMs can be arranged with dilute acid solution treatment. In this study, two different columns structures were prepared. After a surface modification to decrease their surface energy, AAMs were treated with PC solution. Following the solvent evaporation, nanopatterned PC films with tunable pillared structures were peeled off from the membrane surface. The PC film was then modified with Au and Thioflavin-T for the detection of Amyloid-β 1-42 protein. The protein detection studies were conducted first in water via this biosensor platform. Same measurements were conducted in artificial saliva to detect the presence of Amyloid Amyloid-β 1-42 protein. SEM, SERS and contact angle measurements were carried out for the characterization of different surfaces and further demonstration of the protein attachment. SERS enhancement factor calculations were also completed via experimental results. As a result, our research group fabricated diagnostic test models that utilize Au-coated nanopatterned polycarbonate (PC) surfaces modified with Thioflavin-T to detect low concentrations of Alzheimer’s Amiloid – β protein in water and artificial saliva medium. This work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) Grant No: 214Z167.Keywords: alzheimer, anodic aluminum oxide, nanotopography, surface enhanced Raman spectroscopy
Procedia PDF Downloads 2915014 A Similarity/Dissimilarity Measure to Biological Sequence Alignment
Authors: Muhammad A. Khan, Waseem Shahzad
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Analysis of protein sequences is carried out for the purpose to discover their structural and ancestry relationship. Sequence similarity determines similar protein structures, similar function, and homology detection. Biological sequences composed of amino acid residues or nucleotides provide significant information through sequence alignment. In this paper, we present a new similarity/dissimilarity measure to sequence alignment based on the primary structure of a protein. The approach finds the distance between the two given sequences using the novel sequence alignment algorithm and a mathematical model. The algorithm runs at a time complexity of O(n²). A distance matrix is generated to construct a phylogenetic tree of different species. The new similarity/dissimilarity measure outperforms other existing methods.Keywords: alignment, distance, homology, mathematical model, phylogenetic tree
Procedia PDF Downloads 1785013 Emergence of Fluoroquinolone Resistance in Pigs, Nigeria
Authors: Igbakura I. Luga, Alex A. Adikwu
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A comparison of resistance to quinolones was carried out on isolates of Shiga toxin-producing Escherichia coliO157:H7 from cattle and mecA and nuc genes harbouring Staphylococcus aureus from pigs. The isolates were separately tested in the first and current decades of the 21st century. The objective was to demonstrate the dissemination of resistance to this frontline class of antibiotic by bacteria from food animals and bring to the limelight the spread of antibiotic resistance in Nigeria. A total of 10 isolates of the E. coli O157:H7 and 9 of mecA and nuc genes harbouring S. aureus were obtained following isolation, biochemical testing, and serological identification using the Remel Wellcolex E. coli O157:H7 test. Shiga toxin-production screening in the E. coli O157:H7 using the verotoxin E. coli reverse passive latex agglutination (VTEC-RPLA) test; and molecular identification of the mecA and nuc genes in S. aureus. Detection of the mecA and nuc genes were carried out using the protocol by the Danish Technical University (DTU) using the following primers mecA-1:5'-GGGATCATAGCGTCATTATTC-3', mecA-2: 5'-AACGATTGTGACACGATAGCC-3', nuc-1: 5'-TCAGCAAATGCATCACAAACAG-3', nuc-2: 5'-CGTAAATGCACTTGCTTCAGG-3' for the mecA and nuc genes, respectively. The nuc genes confirm the S. aureus isolates and the mecA genes as being methicillin-resistant and so pathogenic to man. The fluoroquinolones used in the antibiotic resistance testing were norfloxacin (10 µg) and ciprofloxacin (5 µg) in the E. coli O157:H7 isolates and ciprofloxacin (5 µg) in the S. aureus isolates. Susceptibility was tested using the disk diffusion method on Muller-Hinton agar. Fluoroquinolone resistance was not detected from isolates of E. coli O157:H7 from cattle. However, 44% (4/9) of the S. aureus were resistant to ciprofloxacin. Resistance of up to 44% in isolates of mecA and nuc genes harbouring S. aureus is a compelling evidence for the rapid spread of antibiotic resistance from bacteria in food animals from Nigeria. Ciprofloxacin is the drug of choice for the treatment of Typhoid fever, therefore widespread resistance to it in pathogenic bacteria is of great public health significance. The study concludes that antibiotic resistance in bacteria from food animals is on the increase in Nigeria. The National Food and Drug Administration and Control (NAFDAC) agency in Nigeria should implement the World Health Organization (WHO) global action plan on antimicrobial resistance. A good starting point can be coordinating the WHO, Office of International Epizootics (OIE), Food and Agricultural Organization (FAO) tripartite draft antimicrobial resistance monitoring and evaluation (M&E) framework in Nigeria.Keywords: Fluoroquinolone, Nigeria, resistance, Staphylococcus aureus
Procedia PDF Downloads 4585012 Effects of Alkaline Pretreatment Parameters on the Corrosion Resistance and Wettability of Magnesium Implant
Authors: Mahtab Assadian, Mohd Hasbullah Idris, Mostafa Rezazadeh Shirdar, Mohammad Mahdi Taheri, S. Izman
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Corrosion behaviour and surface roughness of magnesium substrate were investigated after NaOH pretreatment in different concentrations (1, 5, and 10 molar) and duration of (10 min, 30 min, 1 h, 3 h, 6 h and 24 h). Creation of Mg(OH)2 barrier layer after pretreatment enhanced corrostion resistance as well as wettability of substrate surface. Characterization including Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) was conducted to detect the existence of this barrier layer. Surface roughness and wettability of substrate was evaluated using atomic force microscopy (AFM) and contact angle measurement respectively. It is found that magnesium treated by 1M NaOH for 30 min reveals higher corrosion resistance and lower water contact angle of substrate surface. In addition, this investigation indicates that pH value of SBF solution is strongly influenced by different time and concentration of alkaline pretreatment.Keywords: magnesium, NaOH pretreatment, corrosion resistance, wettability
Procedia PDF Downloads 9615011 From Genome to Field: Applying Genome Wide Association Study for Sustainable Ascochyta Blight Management in Faba Beans
Authors: Rabia Faridi, Rizwana Maqbool, Umara Sahar Rana, Zaheer Ahmad
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Climate change impacts agriculture, notably in Germany, where spring faba beans predominate. However, improved winter hardiness aligns with milder winters, enabling autumn-sown varieties. Genetic resistance to Ascochyta blight is vital for crop integration. Traditional breeding faces challenges due to complex inheritance. This study assessed 224 homozygous faba bean lines for Ascochyta resistance traits. To achieve h²>70%, 12 replicates were required (realized h²=87%). Genetic variation and strong trait correlations were observed. Five lines outperformed 29H, while three were highly susceptible. A genome-wide association study (GWAS) with 188 inbred lines and 2058 markers, including 17 guide SNP markers, identified 12 markers associated with resistance traits, potentially indicating new resistance genes. One guide marker (Vf-Mt1g014230-001) on chromosome III validated a known QTL. The guided marker approach complemented GWAS, facilitating marker-assisted selection for Ascochyta resistance. The Göttingen Winter Bean Population offers promise for resistance breeding.Keywords: genome wide association studies, marker assisted breeding, faba bean, ascochyta blight
Procedia PDF Downloads 595010 The Corrosion Resistance of P/M Alumix 431D Compacts
Authors: J. Kazior, A. Szewczyk-Nykiel, T. Pieczonka, M. Laska
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Aluminium alloys are an important class of engineering materials for structural applications. This is due to the fact that these alloys have many interesting properties, namely, low density, high ratio of strength to density, good thermal and electrical conductivity, good corrosion resistance as well as extensive capabilities for shaping processes. In case of classical PM technology a particular attention should be paid to the selection of appropriate parameters of compacting and sintering processes and to keeping them. The latter need arises from the high sensitivity of aluminium based alloy powders on any fluctuation of technological parameters, in particular those related to the temperature-time profile and gas flow. Only then the desired sintered compacts with residual porosity may be produced. Except high mechanical properties, the other profitable properties of almost fully dense sintered components could be expected. Among them is corrosion resistance, rarely investigated on PM aluminium alloys. Thus, in the current study the Alumix 431/D commercial, press-ready grade powder was used for this purpose. Sintered compacts made of it in different conditions (isothermal sintering temperature, gas flow rate) were subjected to corrosion experiments in 0,1 M and 0,5 M NaCl solutions. The potentiodynamic curves were used to establish parameters characterising the corrosion resistance of sintered Alumix 431/D powder, namely, the corrosion potential, the corrosion current density, the polarization resistance, the breakdown potential. The highest value of polarization resistance, the lowest value of corrosion current density and the most positive corrosion potential was obtained for Alumix431/D powder sintered at 600°C and for highest protective gas flow rate.Keywords: aluminium alloys, sintering, corrosion resistance, industry
Procedia PDF Downloads 3465009 Profiling the Volatile Metabolome in Pear Leaves with Different Resistance to the Pear Psylla Cacopsylla bidens (Sulc) and Characterization of Phenolic Acid Decarboxylase
Authors: Mwafaq Ibdah, Mossab, Yahyaa, Dor Rachmany, Yoram Gerchman, Doron Holland, Liora Shaltiel-Harpaz
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Pear Psylla is the most important pest of pear in all pear-growing regions, in Asian, European, and the USA. Pear psylla damages pears in several ways: high-density populations of these insects can cause premature leaf and fruit drop, diminish plant growth, and reduce fruit size. In addition, their honeydew promotes sooty mold on leaves and russeting on fruit. Pear psyllas are also considered vectors of pear pathogens such as Candidatus Phytoplasma pyri causing pear decline that can lead to loss of crop and tree vigor, and sometimes loss of trees. Psylla control is a major obstacle to efficient integrated pest management. Recently we have identified two naturally resistance pear accessions (Py.760-261 and Py.701-202) in the Newe Ya’ar live collection. GC-MS volatile metabolic profiling identified several volatile compounds common in these accessions but lacking, or much less common, in a sensitive accession, the commercial Spadona variety. Among these volatiles were styrene and its derivatives. When the resistant accessions were used as inter-stock, the volatile compounds appear in commercial Spadona scion leaves, and it showed reduced susceptibility to pear psylla. Laboratory experiments and applications of some of these volatile compounds were very effective against psylla eggs, nymphs, and adults. The genes and enzymes involved in the specific reactions that lead to the biosynthesis of styrene in plant are unknown. We have identified a phenolic acid decarboxylase that catalyzes the formation of p-hydroxystyrene, which occurs as a styrene analog in resistant pear genotypes. The His-tagged and affinity chromatography purified E. coli-expressed pear PyPAD1 protein could decarboxylate p-coumaric acid and ferulic acid to p-hydroxystyrene and 3-methoxy-4-hydroxystyrene. In addition, PyPAD1 had the highest activity toward p-coumaric acid. Expression analysis of the PyPAD gene revealed that its expressed as expected, i.e., high when styrene levels and psylla resistance were high.Keywords: pear Psylla, volatile, GC-MS, resistance
Procedia PDF Downloads 1475008 Enhancement of Hardness and Corrosion Resistance of Plasma Nitrided Low Alloy Tool Steel
Authors: Kalimi Trinadh, Corinne Nouveau, A. S. Khanna, Karanveer S. Aneja, K. Ram Mohan Rao
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This study concerns improving the corrosion resistance of low alloy steel after plasma nitriding performed at variable time and temperature. Nitriding carried out in the temperature range of 450-550ᵒC for a various time period of 1-8 hrs. at 500Pa in a glow discharge plasma of H₂ and N₂ (80:20). The substrate was kept biased negatively at 250V. Following nitriding the X-ray diffraction studies shown that the phases formed were mainly γ′ (Fe₄N) and ε (Fe₂₋₃N). The ε (Fe₂₋₃N) phase found to be the dominating phase. Cross sections of the samples under scanning electron microscope point analyses revealed the presence of nitrogen in the surface region. For the assessment of corrosion resistance property, potentiodynamic polarization tests were performed in 3.5% NaCl solution. It has been shown that the plasma nitriding significantly improved the corrosion resistance when compared to the as-received steel. Furthermore, it has also been found that nitriding for 6h has more corrosion resistance than nitriding for the 8h duration. The hardness of the nitrided samples was measured by Vicker’s microhardness tester. The hardness of the nitrided steel was found to be improved much above the hardness of the steel in the as-received condition. It was found to be around two-fold of the initial hardness.Keywords: corrosion, steel, plasma nitriding, X-ray diffraction
Procedia PDF Downloads 1995007 Effect of Micaceous Iron Oxide and Nanocrystalline Al on the Electrochemical Behavior of Aliphatic Amine Cured Epoxy Coating
Authors: Asiful H. Seikh, Jabair A. Mohammed, Ubair A. Samad, Mohammad A. Alam, Saeed M. Al-Zahrani, El-Sayed M. Sherif
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Three coating formulations were fabricated by incorporating different percentages of MIO (micaceous iron oxide ) (1, 2, and wt%) with ball-milled nanocrystalline Al (2 wt%) particles, which was optimized earlier. These coatings were characterized by means of different methods, namely, SEM, TGA, pendulum hardness, scratch test, and nano-indentation. The EIS measurements were carried out to report the effect of adding MIO powder in fabricated coatings on their corrosion behavior in 3.5 wt% NaCl solutions. In order to report the effect of immersion time on the corrosion and degradation of the prepared coatings, the EIS data were also acquired after various exposure periods of time, i.e., 1 h, 7 d, 14 d, 21 d, and 30 d in the test chloride solution. It has been found that the obtained EIS data for the fabricated coatings proved that the presence of 2% MIO provided the highest corrosion resistance amongst all coatings and that effect was recorded after all immersion periods of time. But, the MIO-incorporated coatings have less corrosion resistance than Al based epoxy coatings. It was also shown that with prolonged immersion, the resistance to corrosion declined after 7d, then with a longer period of immersion, i.e. 14 d, 21 d, and 30 d increases the resistance to corrosion by forming oxide products on the coatings surface. The results obtained from both mechanical and electrochemical testing confirmed that the fabricated coating with 2 wt% Al exhibited better hardness and higher resistance to corrosion as compared to coatings with 1 wt% Al and 3 wt% Al.Keywords: epoxy coatings, nanomaterials, corrosion resistance, EIS, nanoindentation
Procedia PDF Downloads 725006 Laser Welding Technique Effect for Proton Exchange Membrane Fuel Cell Application
Authors: Chih-Chia Lin, Ching-Ying Huang, Cheng-Hong Liu, Wen-Lin Wang
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A complete fuel cell stack comprises several single cells with end plates, bipolar plates, gaskets and membrane electrode assembly (MEA) components. Electrons generated from cells are conducted through bipolar plates. The amount of cells' components increases as the stack voltage increases, complicating the fuel cell assembly process and mass production. Stack assembly error influence cell performance. PEM fuel cell stack importing laser welding technique could eliminate transverse deformation between bipolar plates to promote stress uniformity of cell components as bipolar plates and MEA. Simultaneously, bipolar plates were melted together using laser welding to decrease interface resistance. A series of experiments as through-plan and in-plan resistance measurement test was conducted to observe the laser welding effect. The result showed that the through-plane resistance with laser welding was a drop of 97.5-97.6% when the contact pressure was about 1MPa to 3 MPa, and the in-plane resistance was not significantly different for laser welding.Keywords: PEM fuel cell, laser welding, through-plan, in-plan, resistance
Procedia PDF Downloads 5115005 Molecular Portraits: The Role of Posttranslational Modification in Cancer Metastasis
Authors: Navkiran Kaur, Apoorva Mathur, Abhishree Agarwal, Sakshi Gupta, Tuhin Rashmi
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Aim: Breast cancer is the most common cancer in women worldwide, and resistance to the current therapeutics, often concurrently, is an increasing clinical challenge. Glycosylation of proteins is one of the most important post-translational modifications. It is widely known that aberrant glycosylation has been implicated in many different diseases due to changes associated with biological function and protein folding. Alterations in cell surface glycosylation, can promote invasive behavior of tumor cells that ultimately lead to the progression of cancer. In breast cancer, there is an increasing evidence pertaining to the role of glycosylation in tumor formation and metastasis. In the present study, an attempt has been made to study the disease associated sialoglycoproteins in breast cancer by using bioinformatics tools. The sequence will be retrieved from UniProt database. A database in the form of a word document was made by a collection of FASTA sequences of breast cancer gene sequence. Glycosylation was studied using yinOyang tool on ExPASy and Differential genes expression and protein analysis was done in context of breast cancer metastasis. The number of residues predicted O-glc NAc threshold containing 50 aberrant glycosylation sites or more was detected and recorded for individual sequence. We found that the there is a significant change in the expression profiling of glycosylation patterns of various proteins associated with breast cancer. Differential aberrant glycosylated proteins in breast cancer cells with respect to non-neoplastic cells are an important factor for the overall progression and development of cancer.Keywords: breast cancer, bioinformatics, cancer, metastasis, glycosylation
Procedia PDF Downloads 2945004 Tofu Flour as a Protein Sources
Authors: Dicky Eka Putra, S. P. Nadia Chairunissa, Lidia Paramita, Roza Hartati, Ice Yolanda Puri
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Background: Soy bean and the products such as tofu, tempeh and soy milk are famous in the community. Moreover, another product is tofu flour which is not familiar in Indonesia yet and it is well known as Okara. There are massive differences of energy, protein and carbohydrate between them which is know as good for protein sources as well. Unfortunately, it is seldom used as food variety. Basically, it can be benefit in order to create many products for example cakes, snacks and some desserts. Aim: the study was in order to promote the benefit of tofu flour as school feeding of elementary school and baby porridge and also to compare the nutrient. Method: Soy pulp was filtered and steamed approximately 30 minutes. Then, it was put at a plate under sunrise or barked on the oven for 10 hours at 800C. When it have dried and milling and tofu flour is ready to be used. Result: Tofu flour could be used as substitute of flour and rice flour when people want to cook some foods. In addition, some references said that soy bean is good for a specific remedy for the proper functioning of the heart, liver, kidneys, stomach, and bowels, constipation, as a stimulant for the lungs, for eradication of poison from the system, improving the complexion by cleaning the skin of impurities, and stimulating the growth and appearance of the hair. Discussion: Comparing between soy bean, tofu and tofu flour which has difference amount of nutrients. For example energy 382 kcal, 79 kcal and 393 kcal respectively and also protein 30.2 kcal, 7.8 kcal, and 17.4 kcal. In addition, carbohydrate of soy pulp was high than soy bean and tofu (30.1 kcal). Finally, local should replace flour, rice and gelatin rice flour with tofu flour.Keywords: tofu flour, protein, soy bean, school feeding
Procedia PDF Downloads 3785003 Chemical Characterization and Antioxidant Capacity of Flour From Two Soya Bean Cultivars (Glycine Max)
Authors: Meziani Samira, Menadi Noreddine, Labga Lahouaria, Chenni Fatima Zohra, Toumi Asma
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A comparative study between two varieties of soya beans was carried out in this work. The method consists of studying and proceeding to prepare a by-product (Flour) from two varieties of soybeans, a Chinese variety imported and marketed in Algeria. The chemical composition of ash, protein and fat was determined in this study. The minerals, namely potassium and sodium, were measured by flame spectrophotometer. In addition, the estimation of the polyphenol content and evaluation of the antioxidant activity Ferric Reducing Antioxidant Power assay (FRAP) f the methanol extracts of the flours were also carried out. The result revealed that soy flour from two cultivars, on average, contained 8% moisture, more than 50% protein, 1.58-1.87g fat, and 0.28-0.30g of ash. A slight difference was found for contents of 489 mg/ml of K + and 20 mg/ml of NA +. In addition, the phenolic content of the methanolic extracts gives a value of almost 37 mg EAG / g for both cultivars of soy flour. The estimated Reductive Antioxidant Iron (FRAP) potency of soy flour might be related to its polyphenol richness, which is similar to the variety of China. The flour Soya varieties tested contained a significant amount of protein and phenolic compounds with good antioxidant properties.Keywords: soye beans, soya flour, protein, total polyphenols
Procedia PDF Downloads 905002 Ribosomal Protein S4 Gene: Exploring the Presence in Syrian Strain of Leishmania Tropica Genome, Sequencing it and Evaluating Immune Response of pCI-S4 DNA Vaccine
Authors: Alyaa Abdlwahab
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Cutaneous leishmaniasis represents a serious health problem in Syria; this problem has become noticeably aggravated after the civil war in the country. Leishmania tropica parasite is the main cause of cutaneous leishmaniasis in Syria. In order to control the disease, we need an effective vaccine against leishmania parasite. DNA vaccination remains one of the favorable approaches that have been used to face cutaneous leishmaniasis. Ribosomal protein S4 is responsible for important roles in Leishmania parasite life. DNA vaccine based on S4 gene has been used against infections by many species of Leishmania parasite but leishmania tropica parasite, so this gene represents a good candidate for DNA vaccine construction. After proving the existence of ribosomal protein S4 gene in a Syrian strain of Leishmania tropica (LCED Syrian 01), sequencing it and cloning it into pCI plasmid, BALB/C mice were inoculated with pCI-S4 DNA vaccine. The immune response was determined by monitoring the lesion progression in inoculated BALB/C mice for six weeks after challenging mice with Leishmania tropica (LCED Syrian 01) parasites. IL-12, IFN-γ, and IL-4 were quantified in draining lymph nodes (DLNa) of the immunized BALB/C mice by using the RT-qPCR technique. The parasite burden was calculated in the final week for the footpad lesion and the DLNs of the mice. This study proved the existence and the expression of the ribosomal protein S4 gene in Leishmania tropica (LCED Syrian 01) promastigotes. The sequence of ribosomal protein cDNA S4 gene was determined and published in Genbank; the gene size was 822 bp. Expression was also demonstrated at the level of cDNA. Also, this study revealed that pCI-S4 DNA vaccine induces TH1\TH2 response in immunized mice; this response prevents partially developing a dermal lesion of Leishmania.Keywords: ribosomal protein S4, DNA vaccine, Leishmania tropica, BALB\c
Procedia PDF Downloads 1365001 The Role of Estradiol-17β and Type IV Collagen on the Regulation and Expression Level Of C-Erbb2 RNA and Protein in SKOV-3 Ovarian Cancer Cell Line
Authors: Merry Meryam Martgrita, Marselina Irasonia Tan
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One of several aggresive cancer is cancer that overexpress c-erbB2 receptor along with the expression of estrogen receptor. Components of extracellular matrix play an important role to increase cancer cells proliferation, migration and invasion. Both components can affect cancer development by regulating the signal transduction pathways in cancer cells. In recent research, SKOV-3 ovarian cancer cell line, that overexpress c-erbB2 receptor was cultured on type IV collagen and treated with estradiol-17β, to reveal the role of both components on RNA and protein level of c-erbB2 receptor. In this research we found a modulation phenomena of increasing and decreasing of c-erbB2 RNA level and a stabilisation phenomena of c-erbB2 protein expression due to estradiol-17β and type IV collagen. It seemed that estradiol-17β has an important role to increase c-erbB2 transcription and the stability of c-erbB2 protein expression. Type IV collagen has an opposite role. It blocked c-erbB2 transcription when it bound to integrin receptor in SKOV-3 cells.Keywords: c-erbB2, estradiol-17β, SKOV-3, type IV collagen
Procedia PDF Downloads 2845000 Functional Significance of Qatari Camels Milk: Antioxidant Content and Antimicrobial Activity of Protein Fractions
Authors: Tahra ElObeid, Omnya Ahmed, Reem Al-Sharshani, Doaa Dalloul, Jannat Alnattei
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Background: Camelus dormedarius camels are also called ‘the Arabian camels’ and are present in the desert area of North Africa and the Middle East. Recently, camel’s milk has a great attention globally because of their proteins and peptides that have been reported to be beneficial for the health and in the management of many diseases. Objectives: This study was designed to investigate the antioxidant, antimicrobial activity and to evaluate the total phenolic content of camel’s milk proteins in Qatar. Methods: Fresh two camel’s milk samples from Omani breed and called Muhajer (camel’s milk A and B) were collected on the 1st of the December. Both samples were from the same location Al- Shahaniyah, Doha, Qatar, but from different local private farms and feeding system. Camel’s milk A and B were defatted by centrifugation and their proteins were extracted by acid and thermal precipitation. The antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Total phenolic compound (TPC) was evaluated by Folin-Ciocalteu reagent (FCR). On the other hand, the antimicrobial activity against eight different type of pathogenic bacteria was evaluated by disc diffusion method and the zone of inhibition was measured. Results: The of the total phenolic content of whole milk in both camel’s milk A and B were significantly the highest among the protein extracts. The % of the DPPH radical inhibition of casein protein in both camel’s milk A and B were significantly the highest among the protein extracts. In this study, there were marked changes in the antibacterial activity in the different camel milk protein extracts. All extracts showed bacterial overgrowth. Conclusion: The antioxidant activity of the camel milk protein extracts correlated to their unique phenolic compounds and bioactive protein peptides. The antimicrobial activity was not detected perhaps due to the technique, the quality, or the extraction method. Overall, camel's milk exhibits a high antioxidant activity, which is responsible for many health benefits besides the nutritional values.Keywords: camels milk, antioxidant content, antimicrobial activity, proteins, Qatar
Procedia PDF Downloads 2144999 Effect of Fenugreek Seed with Aerobic Exercise Training on Insulin Resistance in Women with Type 2 Diabetes
Authors: M. Nasiri
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Aim: Considering the hypoglisimic ad hipolipidimic effect of the fenugreek seed and aerobic exercise training, this study was conducted to evaluate the effect of fenugreek and aerobic exercise training on insulin resistance in women with type 2 diabetes. Methodology: 32 patients with type II diabetes were selected and randomly divided into four groups: control, fenugreek, training and fenugreek - training. Fenugreek groups used 10 grams of fenugreek seeds daily for eight weeks on two occasions before noon and evening meal. Training of groups is also performed a regular program of aerobic exercise 65-55% of maximum heart rate (4 days per week).Two days before and after the training period, blood samples were taken from their brachial veins in a fasting state (12 hours prior to the test) in a sitting position. The data was analyzed used of t-independent and ANOVA at a significance level of α < 0.05. Results: Intra-group changes in all experimental groups showed that significant decrease insulin resistance, and the difference between groups showed significant difference between the groups of fenugreek - training than other groups there. Conclusions: According to the research findings to fenugreek combined with aerobic exercise more beneficial effect on the inhibition of insulin resistance in women with diabetes are recommended to them.Keywords: fenugreek, training, insulin resistance, diabetes
Procedia PDF Downloads 4484998 Improving the Corrosion Resistance of Magnesium by Application of TiO₂-MgO Coatings
Authors: Eric Noe Hernandez Rodriguez, Cristian Esneider Penuela Cruz
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Magnesium is a biocompatible and biodegradable material that has gained increased interest for application in resorbable orthopedic implants. However, to date, much research is being conducted to overcome the main disadvantage: its low corrosion resistance. In this work, we report our findings on the development and application of TiO₂-MgO coatings to improve and modulate the corrosion resistance of magnesium pieces. The plasma electrolytic oxidation (PEO) technique was employed to obtain the TiO₂-MgO coatings. The effect of the experimental parameters on the modulation of the TiO₂:MgO ratio was investigated. The most critical parameters were the chemical composition of the precursor electrolytic solution and the current density. According to scanning electron microscopy (SEM) observations, the coatings were porous; however, they become more compact as the current density increases. XRD measurements showed that the coatings are formed by a composite consisting of TiO₂ and MgO oxides, whose ratio can be changed by the experimental conditions. TiO₂ had the anatase crystalline structure, while the MgO had the FCC crystalline structure. The corrosion resistance was evaluated through the corrosion current (Icorr) measured at room temperature by the polarization technique (Tafel). For doing it, Hank's solution was used in order to simulate the body fluids. Also, immersion tests were conducted. Tafel curves showed an improvement of the corrosion resistance at some coated magnesium pieces in contrast to control pieces (uncoated). Corrosion currents were lower, and the corrosion potential changed to positive values. It was observed that the experimental parameters allowed to modulate the protective capacity of the coatings by changing the TiO₂:MgO ratio. Coatings with a higher content of TiO₂ (measured by energy dispersive spectroscopy) showed higher corrosion resistance. Results showed that TiO₂-MgO coatings can be successfully applied to improve the corrosion resistance of Mg pieces in simulated body fluid; even more, the corrosion resistance can be tuned by changing the TiO₂:MgO ratio.Keywords: biomaterials, PEO, corrosion resistance, magnesium
Procedia PDF Downloads 1044997 The Influence of Psychological Capital Dimensions to Performance through OCB with Resistance to Change as Moderating Variable
Authors: Bambang Suko Priyono, Tristiana Rijanti
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This study examines the influence of Psychological Capital Dimensions to Organizational Citizenship Behavior. There are four dimensions of Psychological Capital such as hope, optimism, resilience, and self-efficacy. It also tests the moderation effect of Resistance to Change in the relation between Psychological Capital’s dimensions and Organizational Citizenship Behavior, and the influence of Organizational Citizenship Behavior to employees’ performance. The data from the chosen 160 respondents from Public Service Institution is processed using multiple regression and interaction method. The study results in: 1) Hope positively significantly influences Organizational Citizenship Behavior, 2) Optimism positively significantly influences Organizational Citizenship Behavior, 3) Resilience positively significantly influences Organizational Citizenship Behavior, 4) Self-efficacy positively significantly influences Organizational Citizenship Behavior, 5) Resistance to change is moderating variable between hope and Organizational Citizenship Behavior, 6) Resistance to change is moderating variable between self-efficacy and Organizational Citizenship Behavior, 7) Organizational Citizenship Behavior positively significantly influences performance. On the contrary, resistance to change as a moderating variable is proven for hope and resilience.Keywords: organizational citizenship behavior, performance, psychological capital’s dimensions, and resistance to change
Procedia PDF Downloads 6854996 Testing of Protective Coatings on Automotive Steel, a Correlation Between Salt Spray, Electrochemical Impedance Spectroscopy, and Linear Polarization Resistance Test
Authors: Dhanashree Aole, V. Hariharan, Swati Surushe
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Corrosion can cause serious and expensive damage to the automobile components. Various proven techniques for controlling and preventing corrosion depend on the specific material to be protected. Electrochemical Impedance Spectroscopy (EIS) and salt spray tests are commonly used to assess the corrosion degradation mechanism of coatings on metallic surfaces. While, the only test which monitors the corrosion rate in real time is known as Linear Polarisation Resistance (LPR). In this study, electrochemical tests (EIS & LPR) and spray test are reviewed to assess the corrosion resistance and durability of different coatings. The main objective of this study is to correlate the test results obtained using linear polarization resistance (LPR) and Electrochemical Impedance Spectroscopy (EIS) with the results obtained using standard salt spray test. Another objective of this work is to evaluate the performance of various coating systems- CED, Epoxy, Powder coating, Autophoretic, and Zn-trivalent coating for vehicle underbody application. The corrosion resistance coating are assessed. From this study, a promising correlation between different corrosion testing techniques is noted. The most profound observation is that electrochemical tests gives quick estimation of corrosion resistance and can detect the degradation of coatings well before visible signs of damage appear. Furthermore, the corrosion resistances and salt spray life of the coatings investigated were found to be according to the order as follows- CED> powder coating > Autophoretic > epoxy coating > Zn- Trivalent plating.Keywords: Linear Polarization Resistance (LPR), Electrochemical Impedance Spectroscopy (EIS), salt spray test, sacrificial and barrier coatings
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