Search results for: frost resistance of samples
7655 Utilization Of Guar Gum As Functional Fat Replacer In Goshtaba, A Traditional Indian Meat Product
Authors: Sajad A. Rather, F. A. Masoodi, Rehana Akhter, S. M. Wani, Adil Gani
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Modern trend towards convenience foods has resulted in increased production and consumption of restructured meat products and are of great importance to the meat industry. In meat products fat plays an important role in cooking properties, texture & sensory scores, however, high fat contents in particular animal fats provide high amounts of saturated fatty acids and cholesterol and are associated with several types of non communicable diseases such as obesity, hypertension and coronary heart diseases. Thus, fat reduction has generally been seen as an important strategy to produce healthier meat products. This study examined the effects of reducing fat level from 20% to 10% and substituting mutton back fat with guar gum (0.5%, 1% & 1.5%) on cooking properties, proximate composition, lipid and protein oxidation, texture, microstructure and sensory characteristics of goshtaba- a traditional meat product of J & K, India were investigated and compared with high fat counterparts. Reduced- fat goshtaba samples containing guar gum had significantly (p ≤ 0.05) higher yield, less shrinkage, more moisture retention and more protein content than the control sample. TBARs and protein oxidation (carbonyl content) values of the control was significantly (p ≤ 0.05) higher than reduced fat goshtaba samples and showed a positive correlation between lipid and protein oxidation. Hardness, gumminess & chewiness of the control (20%) were significantly higher than reduced fat goshtaba samples. Microstructural differences were significant (p ≤ 0.05) between control and treated samples due to an increased moisture content in the reduced fat samples. Sensory evaluation showed significant (p ≤ 0.05) reduction in texture, flavour and overall acceptability scores of treatment products; however the scores for 0.5% and 1% treated samples were in the range of acceptability. Guar gum may also be used as a source of soluble dietary fibre in food products and a number of clinical studies have shown a reduction in postprandial glycemia and insulinemia on consumption of guar gum, with the mechanism being attributed to an increased transit time in the stomach and small intestine, which may have been due to the viscosity of the meal hindering the access of glucose to the epithelium.Keywords: goshtaba, guar gum, traditional, fat reduction, acceptability
Procedia PDF Downloads 2787654 Miniaturized PVC Sensors for Determination of Fe2+, Mn2+ and Zn2+ in Buffalo-Cows’ Cervical Mucus Samples
Authors: Ahmed S. Fayed, Umima M. Mansour
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Three polyvinyl chloride membrane sensors were developed for the electrochemical evaluation of ferrous, manganese and zinc ions. The sensors were used for assaying metal ions in cervical mucus (CM) of Egyptian river buffalo-cows (Bubalus bubalis) as their levels vary dependent on cyclical hormone variation during different phases of estrus cycle. The presented sensors are based on using ionophores, β-cyclodextrin (β-CD), hydroxypropyl β-cyclodextrin (HP-β-CD) and sulfocalix-4-arene (SCAL) for sensors 1, 2 and 3 for Fe2+, Mn2+ and Zn2+, respectively. Dioctyl phthalate (DOP) was used as the plasticizer in a polymeric matrix of polyvinylchloride (PVC). For increasing the selectivity and sensitivity of the sensors, each sensor was enriched with a suitable complexing agent, which enhanced the sensor’s response. For sensor 1, β-CD was mixed with bathophenanthroline; for sensor 2, porphyrin was incorporated with HP-β-CD; while for sensor 3, oxine was the used complexing agent with SCAL. Linear responses of 10-7-10-2 M with cationic slopes of 53.46, 45.01 and 50.96 over pH range 4-8 were obtained using coated graphite sensors for ferrous, manganese and zinc ionic solutions, respectively. The three sensors were validated, according to the IUPAC guidelines. The obtained results by the presented potentiometric procedures were statistically analyzed and compared with those obtained by atomic absorption spectrophotometric method (AAS). No significant differences for either accuracy or precision were observed between the two techniques. Successful application for the determination of the three studied cations in CM, for the purpose to determine the proper time for artificial insemination (AI) was achieved. The results were compared with those obtained upon analyzing the samples by AAS. Proper detection of estrus and correct time of AI was necessary to maximize the production of buffaloes. In this experiment, 30 multi-parous buffalo-cows were in second to third lactation and weighting 415-530 kg, and were synchronized with OVSynch protocol. Samples were taken in three times around ovulation, on day 8 of OVSynch protocol, on day 9 (20 h before AI) and on day 10 (1 h before AI). Beside analysis of trace elements (Fe2+, Mn2+ and Zn2+) in CM using the three sensors, the samples were analyzed for the three cations and also Cu2+ by AAS in the CM samples and blood samples. The results obtained were correlated with hormonal analysis of serum samples and ultrasonography for the purpose of determining of the optimum time of AI. The results showed significant differences and powerful correlation with Zn2+ composition of CM during heat phase and the ovulation time, indicating that the parameter could be used as a tool to decide optimal time of AI in buffalo-cows.Keywords: PVC Sensors, buffalo-cows, cyclodextrins, atomic absorption spectrophotometry, artificial insemination, OVSynch protocol
Procedia PDF Downloads 2197653 Fire Smoke Removal over Cu-Mn-Ce Oxide Catalyst with CO₂ Sorbent Addition: Co Oxidation and in-situ CO₂ Sorption
Authors: Jin Lin, Shouxiang Lu, Kim Meow Liew
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In a fire accident, fire smoke often poses a serious threat to human safety especially in the enclosed space such as submarine and space-crafts environment. Efficient removal of the hazardous gas products particularly a large amount of CO and CO₂ gases from these confined space is critical for the security of the staff and necessary for the post-fire environment recovery. In this work, Cu-Mn-Ce composite oxide catalysts coupled with CO₂ sorbents were prepared using wet impregnation method, solid-state impregnation method and wet/solid-state impregnation method. The as-prepared samples were tested dynamically and isothermally for CO oxidation and CO₂ sorption and further characterized by the X-ray diffraction (XRD), nitrogen adsorption and desorption, and field emission scanning electron microscopy (FE-SEM). The results showed that all the samples were able to catalyze CO into CO₂ and capture CO₂ in situ by chemisorption. Among all the samples, the sample synthesized by the wet/solid-state impregnation method showed the highest catalytic activity toward CO oxidation and the fine ability of CO₂ sorption. The sample prepared by the solid-state impregnation method showed the second CO oxidation performance, while the coupled sample using the wet impregnation method exhibited much poor CO oxidation activity. The various CO oxidation and CO₂ sorption properties of the samples might arise from the different dispersed states of the CO₂ sorbent in the CO catalyst, owing to the different preparation methods. XRD results confirmed the high-dispersed sorbent phase in the samples prepared by the wet and solid impregnation method, while that of the sample prepared by wet/solid-state impregnation method showed the larger bulk phase as indicated by the high-intensity diffraction peaks. Nitrogen adsorption and desorption results further revealed that the latter sample had a higher surface area and pore volume, which were beneficial for the CO oxidation over the catalyst. Hence, the Cu-Mn-Ce oxide catalyst coupled with CO₂ sorbent using wet/solid-state impregnation method could be a good choice for fire smoke removal in the enclosed space.Keywords: CO oxidation, CO₂ sorption, preparation methods, smoke removal
Procedia PDF Downloads 1397652 Wear Assessment of SS316l-Al2O3 Composites for Heavy Wear Applications
Authors: Catherine Kuforiji, Michel Nganbe
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The abrasive wear of composite materials is a major challenge in highly demanding wear applications. Therefore, this study focuses on fabricating, testing and assessing the properties of 50wt% SS316L stainless steel–50wt% Al2O3 particle composites. Composite samples were fabricated using the powder metallurgy route. The effects of the powder metallurgy processing parameters and hard particle reinforcement were studied. The microstructure, density, hardness and toughness were characterized. The wear behaviour was studied using pin-on-disc testing under dry sliding conditions. The highest hardness of 1085.2 HV, the highest theoretical density of 94.7% and the lowest wear rate of 0.00397 mm3/m were obtained at a milling speed of 720 rpm, a compaction pressure of 794.4 MPa and sintering at 1400 °C in an argon atmosphere. Compared to commercial SS316 and fabricated SS316L, the composites had 7.4 times and 11 times lower wear rate, respectively. However, the commercial 90WC-10Co showed 2.2 times lower wear rate compared to the fabricated SS316L-Al2O3 composites primarily due to the higher ceramic content of 90 wt.% in the reference WC-Co. However, eliminating the relatively high porosity of about 5 vol% using processes such as HIP and hot pressing can be expected to lead to further substantial improvements of the composites wear resistance.Keywords: SS316L, Al2O3, powder metallurgy, wear characterization
Procedia PDF Downloads 3047651 Residual Modulus of Elasticity of Self-Compacting Concrete Incorporated Unprocessed Waste Fly Ash after Expose to the Elevated Temperature
Authors: Mohammed Abed, Rita Nemes, Salem Nehme
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The present study experimentally investigated the impact of incorporating unprocessed waste fly ash (UWFA) on the residual mechanical properties of self-compacting concrete (SCC) after exposure to elevated temperature. Three mixtures of SCC have been produced by replacing the cement mass by 0%, 15% and 30% of UWFA. Generally, the fire resistance of SCC has been enhanced by replacing the cement up to 15% of UWFA, especially in case of residual modulus of elasticity which considers more sensitive than other mechanical properties at elevated temperature. However, a strong linear relationship has been observed between the residual flexural strength and modulus of elasticity, where both of them affected significantly by the cracks appearance and propagation as a result of elevated temperature. Sustainable products could be produced by incorporating unprocessed waste powder materials in the production of concrete, where the waste materials, CO2 emissions, and the energy needed for processing are reduced.Keywords: self-compacting high-performance concrete, unprocessed waste fly ash, fire resistance, residual modulus of elasticity
Procedia PDF Downloads 1357650 The Effect of Filter Cake Powder on Soil Stability Enhancement in Active Sand Dunes, In the Long and Short Term
Authors: Irit Rutman Halili, Tehila Zvulun, Natali Elgabsi, Revaya Cohen, Shlomo Sarig
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Active sand dunes (ASD) may cause significant damage to field crops and livelihood, and therefore, it is necessary to find a treatment that would enhance ADS soil stability. Biological soil crusts (biocrusts) contain microorganisms on the soil surface. Metabolic polysaccharides secreted by biocrust cyanobacteria glue the soil particles into aggregates, thereby stabilizing the soil surface. Filter cake powder (FCP) is a waste by-product in the final stages of the production of sugar from sugarcane, and its disposal causes significant environmental pollution. FCP contains high concentrations of polysaccharides and has recently been shown to be soil stability enhancing agent in ASD. It has been reported that adding FCP to the ASD soil surface by dispersal significantly increases the level of penetration resistance of soil biocrust (PRSB) nine weeks after a single treatment. However, it was not known whether a similar effect could be obtained by administering the FCP in liquid form by means of spraying. It has now been found that spraying a water solution of FCP onto the ASD soil surface significantly increased the level of penetration resistance of soil biocrust (PRSB) three weeks after a single treatment. These results suggest that FCP spraying can be used as a short-term soil stability-enhancing agent for ASD, while administration by dispersal might be more efficient over the long term. Finally, an additional benefit of using FCP as a soil stabilizer, either by dispersal or by spraying, is the reduction in environmental pollution that would otherwise result from the disposal of FCP solid waste.Keywords: active sand dunes, filter cake powder, biological soil crusts, penetration resistance of soil biocrust
Procedia PDF Downloads 1647649 In-silico Design of Riboswitch Based Potent Inhibitors for Vibrio cholera
Authors: Somdutt Mujwar, Kamal Raj Pardasani
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Cholera pandemics are caused by facultative pathogenic Vibrio cholera bacteria persisting in the countries having warmer climatic conditions as well as the presence of large water bodies with huge amount of organic matter, it is responsible for the millions of deaths annually. Presently the available therapy for cholera is Oral Rehydration Therapy (ORT) with an antibiotic drug. Excessive utilization of life saving antibiotics drugs leads to the development of resistance by the infectious micro-organism against the antibiotic drugs resulting in loss of effectiveness of these drugs. Also, many side effects are also associated with the use of these antibiotic drugs. This riboswitch is explored as an alternative drug target for Vibrio cholera bacteria to overcome the problem of drug resistance as well as side effects associated with the antibiotics drugs. The bacterial riboswitch is virtually screened with 24407 legends to get possible drug candidates. The 10 ligands showing best binding with the riboswitch are selected to design a pharmacophore, which can be utilized to design lead molecules by using the phenomenon of bioisosterism.Keywords: cholera, drug design, ligand, riboswitch, pharmacophore
Procedia PDF Downloads 3517648 Influence of Counterface and Environmental Conditions on the Lubricity of Multilayer Graphene Coatings Produced on Nickel by Chemical Vapour Deposition
Authors: Iram Zahra
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Friction and wear properties of multilayer graphene coatings (MLG) on nickel substrate were investigated at the macroscale, and different failure mechanisms working at the interface of nickel-graphene coatings were evaluated. Multilayer graphene coatings were produced on a nickel substrate using the atmospheric chemical vapour deposition (CVD) technique. Wear tests were performed on the pin-on-disk tribometer apparatus under dry air conditions, and using the saltwater solution, distilled water, and mineral oil lubricants and counterparts used in these wear tests were fabricated of stainless steel, chromium, and silicon nitride. The wear test parameters such as rotational speed, wear track diameter, temperature, relative humidity, and load were 60 rpm, 6 mm, 22˚C, 45%, and 2N, respectively. To analyse the friction and wear behaviour, coefficient of friction (COF) vs time curves were plotted, and the sliding surfaces of the samples and counterparts were examined using the optical microscope. Results indicated that graphene-coated nickel in mineral oil lubrication and dry conditions gave the minimum average value of COP (0.05) and wear track width ( ̴151 µm) against the three different types of counterparts. In contrast, uncoated nickel samples indicated a maximum wear track width ( ̴411 µm) and COF (0.5). Thorough investigation and analysis concluded that graphene-coated samples have two times lower COF and three times lower wear than the bare nickel samples. Furthermore, mechanical failures were significantly lower in the case of graphene-coated nickel. The overall findings suggested that multilayer graphene coatings have drastically decreased wear and friction on nickel substrate at the macroscale under various lubricating conditions and against different counterparts.Keywords: friction, lubricity, multilayer graphene, sliding, wear
Procedia PDF Downloads 1407647 Social Impacts of Gentrification: Protest and Resistance: A Case Study in Monterrey’s City Center
Authors: Paulina Ramirez Leal
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Current debates have examined the effects of market-oriented development on gentrification, as well as the role of urban renewal, interventions, and planning policy in exacerbating this phenomenon. Despite the growing body of research recognizing the social impacts of gentrification, to date, there has been very little research directly investigating how resisting gentrification increases social cohesion, a crucial dimension of urban resilience. This contribution set out to explore these social impacts while identifying the different forms of protest and expressions of resistance to gentrification in Monterrey’s city center. The methods employed include documentary analysis and qualitative methods such as surveys and photographic documentation. Monterrey’s city center's ongoing process of gentrification illustrates the impacts of planning policies, specifically TOD. Some of the unintended consequences of the policy have resulted in inhabitants facing forced inner migration and displacement caused by vandalism of their homes and neighborhoods, as well as losing part of their urban identity.Keywords: gentrification, social impacts, neighborhood identity, urban resilience, Monterrey’s City Center
Procedia PDF Downloads 1057646 Evidence of Microplastic Pollution in the Río Bravo/Rio Grande (Mexico/US Border)
Authors: Stephanie Hernández-Carreón, Judith Virginia Ríos-Arana
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Microplastics (MPs) are plastic particles smaller than 5 mm that has been detected in soil, air, organisms, and mostly water around the world. Most studies have focused on MPs detection in marine waters, and less so in freshwater, such is the case of Mexico, where studies about MPs in freshwaters are limited. One of the most important rivers in the country is The Rio Grande/Río Bravo, a natural border between Mexico and the United States. Its waters serve different purposes, such as fishing, habitat to endemic species, electricity generation, agriculture, and drinking water sources, among others. Despite its importance, the river’s waters have not been analyzed to determine the presence of MPs; therefore, the purpose of this research is to determine if the Rio Bravo/Rio Grande is polluted with microplastics. For doing so, three sites (Borderland, Casa de Adobe, and Guadalupe) along the El Paso-Juárez metroplex have been sampled: 30 L of water were filtered through a plankton net (64 µm) in each site and sediments-composed samples were collected. Water samples and sediments were 1) digested with a hydrogen peroxide solution (30%), 2) resuspended in a calcium chloride solution (1.5 g/cm3) to separate MPs, and 3) filtered through a 0.45 µm nitrocellulose membrane. Processed water samples were dyed with Nile Red (1 mg/ml ethanol) and analyzed by fluorescence microscopy. Two water samples have been analyzed until January 2023: Casa de Adobe and Borderland finding a concentration of 5.67 particles/L and 5.93 particles/L, respectively. Three types of particles were observed: fibers, fragments, and films, fibers being the most abundant. These data, as well as the data obtained from the rest of the samples, will be analyzed by an ANOVA (α=0.05). The concentrations and types of particles found in the Río Bravo correspond with other studies on rivers associated with urban environments and agricultural activities in China, where a range of 3.67—10.7 particles/L was reported in the Wei River. Even though we are in the early stages of the study, and three new sites will be sampled and analyzed in 2023 to provide more data about this issue in the river, this presents the first evidence of microplastic pollution in the Rio Grande.Keywords: microplastics, fresh water, Rio Bravo, fluorescence microscopy
Procedia PDF Downloads 1497645 Improving Biodegradation Behavior of Fabricated WE43 Magnesium Alloy by High-Temperature Oxidation
Authors: Jinge Liu, Shuyuan Min, Bingchuan Liu, Bangzhao Yin, Bo Peng, Peng Wen, Yun Tian
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WE43 magnesium alloy can be additively manufactured via laser powder bed fusion (LPBF) for biodegradable applications, but the as-built WE43 exhibits an excessively rapid corrosion rate. High-temperature oxidation (HTO) was performed on the as-built WE43 to improve its biodegradation behavior. A sandwich structure including an oxide layer at the surface, a transition layer in the middle, and the matrix was generated influenced by the oxidation reaction and diffusion of RE atoms when heated at 525 ℃for 8 hours. The oxide layer consisted of Y₂O₃ and Nd₂O₃ oxides with a thickness of 2-3 μm. The transition layer is composed of α-Mg and Y₂O₃ with a thickness of 60-70 μm, while Mg24RE5 could be observed except α-Mg and Y₂O₃. The oxide layer and transition layer appeared to have an effective passivation effect. The as-built WE43 lost 40% weight after the in vitro immersion test for three days and finally broke into debris after seven days of immersion. The high-temperature oxidation samples kept the structural integrity and lost only 6.88 % weight after 28-day immersion. The corrosion rate of HTO samples was significantly controlled, which improved the biocompatibility of the as-built WE43 at the same time. The samples after HTO had better osteogenic capability according to ALP activity. Moreover, as built WE43 performed unqualified in cell adhesion and hemolytic test due to its excessively rapid corrosion rate. While as for HTO samples, cells adhered well, and the hemolysis ratio was only 1.59%.Keywords: laser powder bed fusion, biodegradable metal, high temperature oxidation, biodegradation behavior, WE43
Procedia PDF Downloads 1057644 Fabrication of Powdery Composites Based Alumina and Its Consolidation by Hot Pressing Method in OXY-GON Furnace
Authors: T. Kuchukhidze, N. Jalagonia, T. Korkia, V. Gabunia, N. Jalabadze, R. Chedia
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In this work, obtaining methods of ultrafine alumina powdery composites and high temperature pressing technology of matrix ceramic composites with different compositions have been discussed. Alumina was obtained by solution combustion synthesis and sol-gel methods. Metal carbides containing powdery composites were obtained by homogenization of finishing powders in nanomills, as well as by their single-step high temperature synthesis .Different types of matrix ceramics composites (α-Al2O3-ZrO2-Y2O3, α-Al2O3- Y2O3-MgO, α-Al2O3-SiC-Y2O3, α-Al2O3-WC-Co-Y2O3, α-Al2O3- B4C-Y2O3, α-Al2O3- B4C-TiB2 etc.) were obtained by using OXYGON furnace. Consolidation of powders were carried out at 1550- 1750°C (hold time - 1 h, pressure - 50 MPa). Corundum ceramics samples have been obtained and characterized by high hardness and fracture toughness, absence of open porosity, high corrosion resistance. Their density reaches 99.5-99.6% TD. During the work, the following devices have been used: High temperature vacuum furnace OXY-GON Industries Inc (USA), Electronic Scanning Microscopes Nikon Eclipse LV 150, Optical Microscope NMM- 800TRF, Planetary mill Pulverisette 7 premium line, Shimadzu Dynamic Ultra Micro Hardness Tester DUH-211S, Analysette 12 Dynasizer.Keywords: α-alumina, consolidation, phase transformation, powdery composites
Procedia PDF Downloads 3467643 Radon Concentration in the Water Samples of Hassan District, Karnataka, India
Authors: T. S. Shashikumar
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Radon is a radioactive gas emitted from radium, a daughter product of uranium that occurs naturally in rocks and soil. Radon, together with its decay products, emits alpha particles that can damage lung tissue. The activity concentration of 222Ra has been analyzed in water samples collected from borewells and rivers in and around Hassan city, Karnataka State, India. The measurements were performed by Emanometry technique. The concentration of 222Rn in borewell waters varies from 18.49±1.89 to 397.26±12.3 Bql-1 with geometric mean 120.48±12.87 Bql-1 and in river waters it varies from 92.63±9.31 to 93.98±9.51 Bql-1 with geometric mean of 93.16±9.33 Bql-1. In the present study, the radon concentrations are higher in Adarshanagar and Viveka Nagar which are found to be 397.26±12.3 Bql-1 and 325.78±32.56 Bql-1. Most of the analysed samples show a 222Rn concentration more than 100 Bql-1 and this can be attributed to the geology of the area where the ground waters are located, which is predominantly of granitic characteristic. The average inhalation dose and ingestion dose in the borewell water are found to be 0.405 and 0.033 µSvy-1; and in river water it is found to be 0.234 and 0.019 µSvy-1, respectively. The average total effective dose rate in borewell waters and river waters are found to be 0.433 and 0.253 µSvy-1, which does not cause any health risk to the population of Hassan region.Keywords: borewell, effective dose, emanometry, 222Rn
Procedia PDF Downloads 4377642 Development of Carrot Puree with Algae for the Elderly with Dysphagia
Authors: Obafemi Akinwotu, Aylin Tas, Tony Taylor, Bukola Onarinde
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The study was conducted to explore the methods and tools to improve texture and preserve the total phenolic and antioxidant compounds of dysphagia foods produced from carrot-based puree with decolourised Chlorella algae. Textural properties (Texture profile analysis [TPA]; the International Dysphagia Diet Standardization Initiative, particle size test [PST]) and rheological properties (viscosity and viscoelastic properties) of carrot puree defrosted by different treatments (microwave, steamer, oven), were characterised using hydrocolloids (guar gum, k. carrageenan, and xanthan gum), and the results were compared to a level 4 commercial sample. DPPH (2,2-diphenyl-1-picrylhydrazyl) antiradical scavenging radicals and total phenolic contents were employed to evaluate the total phenolics, and radical scavenging properties of defrosted carrot puree sonicated carrot puree (20 Hz, 30 min, 60 oC), and vacuum-dried carrot powder with the addition of algae. Results show that the viscosity, viscoelasticity test, TPA, and PST of the commercial sample were comparable to those of guar gum and xanthan gum containing puree, suggesting that they could be used as dysphagia diets. There was no noticeable decolourisation of the Chlorella pigment. Additionally, the use of the microwave, stemmer, and oven for defrosting treatment had an impact on the textural characteristics of the moulded samples upon cooling and also contributed to the reduction in the total phenolic and antioxidant properties of the samples. Sonication treatments of algae exposure reduced the cloudiness of the green pigment and lightened the colour of the samples containing algae, and they also reduced the drying time from 2.5 to 1.5 hours during the preliminary work. The low-temperature vacuum- and freeze-dried samples increased the concentration of the powder and resulted in an increase in the total phenolic content of the dry samples. The dried products may therefore have the potential to become more nutrient-dense to benefit the health of individuals with dysphagia.Keywords: dysphagia, elderly, hydrocolloids, carrot puree
Procedia PDF Downloads 637641 An Investigation on Interface Shear Resistance of Twinwall Units for Tank Structures
Authors: Jaylina Rana, Chanakya Arya, John Stehle
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Hybrid precast twinwall concrete units, mainly used in basement, core and crosswall construction, are now being adopted in water retaining tank structures. Their use offers many advantages compared with conventional in-situ concrete alternatives, however, the design could be optimised further via a deeper understanding of the unique load transfer mechanisms in the system. In the tank application, twinwall units, which consist of two precast concrete biscuits connected by steel lattices and in-situ concrete core, are subject to bending. Uncertainties about the degree of composite action between the precast biscuits and hence flexural performance of the units necessitated laboratory tests to investigate the interface shear resistance. Testing was also required to assess both the leakage performance and buildability of a variety of joint details. This paper describes some aspects of this novel approach to the design/construction of tank structures as well as selected results from some of the tests that were carried out.Keywords: hybrid construction, twinwall, precast construction, composite action
Procedia PDF Downloads 4827640 Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) Pollution Effects on Blood Metabolic Factors of Periophthalmus waltoni from Northern Coast of the Persian Gulf
Authors: Majid Afkhami, Maryam Ehsanpour
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The present study provides information about the nature of adverse effects on fish and the ecological impact that polycyclic aromatic hydrocarbons (PAHs) pollutant are having in the northern coast of Hormuz Strait. The glucose and cholesterol levels were higher in fish from the St3 than in Walton's mudskipper from other stations however St3 samples had lowest total proteins levels. There was a significant positive correlation between glucose and cholesterol with PAHs concentrations in sediment and tissue samples (P<0.05). However, total proteins had adverse significant correlation with PAHs concentrations (P>0.05). The adverse correlation was seen between length and body weight of fish samples with PAHs concentrations. According to the results of this study, the monitoring of contaminants bioaccumulation in the northern part of Hormuz Strait is necessary, because this will give an indication of the temporal and spatial extent of the process, as well as an assessment of the potential impact on aquatic organisms health.Keywords: PAHs, blood metabolic factors, Periophthalmus waltoni, Hormuz Strait
Procedia PDF Downloads 3327639 Identification and Isolation of E. Coli O₁₅₇:H₇ From Water and Wastewater of Shahrood and Neka Cities by PCR Technique
Authors: Aliasghar Golmohammadian, Sona Rostampour Yasouri
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One of the most important intestinal pathogenic strains is E. coli O₁₅₇:H₇. This pathogenic bacterium is transmitted to humans through water and food. E. coli O₁₅₇:H₇ is the main cause of Hemorrhagic colitis (HC), Hemolytic Uremic Syndrome (HUS), Thrombotic Thrombocytopenic Purpura (TTP) and in some cases death. Since E. coli O₁₅₇:H₇ can be transmitted through the consumption of different foods, including vegetables, agricultural products, and fresh dairy products, this study aims to identify and isolate E. coli O₁₅₇:H₇ from wastewater by PCR technique. One hundred twenty samples of water and wastewater were collected by Falcom Sterile from Shahrood and Neka cities. The samples were checked for colony formation after appropriate centrifugation and cultivation in the specific medium of Sorbitol MacConkey Agar (SMAC) and other diagnostic media of E. coli O₁₅₇:H₇. Also, the plates were observed macroscopically and microscopically. Then, the necessary phenotypic tests were performed on the colonies, and finally, after DNA extraction, the PCR technique was performed with specific primers related to rfbE and stx2 genes. The number of 5 samples (6%) out of all the samples examined were determined positive by PCR technique with observing the bands related to the mentioned genes on the agarose gel electrophoresis. PCR is a fast and accurate method to identify the bacteria E. coli O₁₅₇:H₇. Considering that E. coli bacteria is a resistant bacteria and survives in water and food for weeks and months, the PCR technique can provide the possibility of quick detection of contaminated water. Moreover, it helps people in the community control and prevent the transfer of bacteria to healthy and underground water and agricultural and even dairy products.Keywords: E. coli O₁₅₇:H₇, PCR, water, wastewater
Procedia PDF Downloads 657638 Study of Laser Induced Damage Threshold in HfO₂/SiO₂ Multilayer Films after β-Ray Irradiation
Authors: Meihua Fang, Tao Fei
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Post-processing can effectively improve the resistance to laser damage in multilayer films used in a high power laser system. In this work, HfO₂/SiO₂ multilayer films are prepared by e-beam evaporation and then β-ray irradiation is employed as the post-processing method. The particle irradiation affects the laser induced damage threshold (LIDT), which includes defects, surface roughness, packing density, and residual stress. The residual stress that is relaxed during irradiation changes from compressive stress into tensile stress. Our results indicate that appropriate tensile stress can improve LIDT remarkably. In view of the fact that LIDT rises from 8 J/cm² to 12 J/cm², i.e., 50% increase, after the film has been irradiated by 2.2×10¹³/cm² β-ray, the particle irradiation can be used as a controllable and desirable post-processing method to improve the resistance to laser induced damage.Keywords: β-ray irradiation, multilayer film, residual stress, laser-induced damage threshold
Procedia PDF Downloads 1537637 Combined Treatment of Estrogen-Receptor Positive Breast Microtumors with 4-Hydroxytamoxifen and Novel Non-Steroidal Diethyl Stilbestrol-Like Analog Produces Enhanced Preclinical Treatment Response and Decreased Drug Resistance
Authors: Sarah Crawford, Gerry Lesley
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This research is a pre-clinical assessment of anti-cancer effects of novel non-steroidal diethyl stilbestrol-like estrogen analogs in estrogen-receptor positive/ progesterone-receptor positive human breast cancer microtumors of MCF 7 cell line. Tamoxifen analog formulation (Tam A1) was used as a single agent or in combination with therapeutic concentrations of 4-hydroxytamoxifen, currently used as a long-term treatment for the prevention of breast cancer recurrence in women with estrogen receptor positive/ progesterone receptor positive malignancies. At concentrations ranging from 30-50 microM, Tam A1 induced microtumor disaggregation and cell death. Incremental cytotoxic effects correlated with increasing concentrations of Tam A1. Live tumor microscopy showed that microtumos displayed diffuse borders and substrate-attached cells were rounded-up and poorly adherent. A complete cytotoxic effect was observed using 40-50 microM Tam A1 with time course kinetics similar to 4-hydroxytamoxifen. Combined treatment with TamA1 (30-50 microM) and 4-hydroxytamoxifen (10-15 microM) induced a highly cytotoxic, synergistic combined treatment response that was more rapid and complete than using 4-hydroxytamoxifen as a single agent therapeutic. Microtumors completely dispersed or formed necrotic foci indicating a highly cytotoxic combined treatment response. Moreover, breast cancer microtumors treated with both 4-hydroxytamoxifen and Tam A1 displayed lower levels of long-term post-treatment regrowth, a critical parameter of primary drug resistance, than observed for 4-hydroxytamoxifen when used as a single agent therapeutic. Tumor regrowth at 6 weeks post-treatment with either single agent 4-hydroxy tamoxifen, Tam A1 or a combined treatment was assessed for the development of drug resistance. Breast cancer cells treated with both 4-hydroxytamoxifen and Tam A1 displayed significantly lower levels of post-treatment regrowth, indicative of decreased drug resistance, than observed for either single treatment modality. The preclinical data suggest that combined treatment involving the use of tamoxifen analogs may be a novel clinical approach for long-term maintenance therapy in patients with estrogen-receptor positive/progesterone-receptor positive breast cancer receiving hormonal therapy to prevent disease recurrence. Detailed data on time-course, IC50 and tumor regrowth assays post- treatment as well as a proposed mechanism of action to account for observed synergistic drug effects will be presented.Keywords: 4-hydroxytamoxifen, tamoxifen analog, drug-resistance, microtumors
Procedia PDF Downloads 687636 Level of IGF-I and IGFBP-3 in Gingival Crevicular Fluid and Plasma in Patients with Aggressive Periodontitis
Authors: Youjeong Hwang
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Purpose: Insulin-like growth factor-I (IGF-I) promotes B-cell development, immunoglobulin formation, and interleukin-6 (IL-6) production, then regulate the immune response and inflammation. As IGF-I and their receptor also exist in the periodontal tissue, they may affect the immune response caused by periodontal pathogens in aggressive periodontitis (AgP) patients. The function of IGF is regulated by IGF binding proteins (IGFBPs), and IGFBP-3 is known to most abundant in plasma. The aim of the present study was to assess the concentration of IGF-I and IGFBP-3 in plasma and gingival crevicular fluid (GCF) in AgP patients and to find out their association. Methods: Nine patients with AgP (test group) and nine healthy subjects (control group) were included in this study. None of the subjects had a history of systemic disease, smoking or steroids medication. GCF samples were collected by microcapillary pipettes and plasma samples were obtained by venipuncture. Probing pocket depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) were recorded. Samples were assayed for IGF-I and IGFBP-3 levels using ELISA. Results: Mean IGF-I level in GCF was higher in the test group than control. Mean IGF-I level in plasma and IGFBP-3 level in GCF and plasma in control group were higher than that of the test group. However, there was no statistical significance (p > 0.05). The mean level of IGF-I and IGFBP-3 in GCF was lower than those in plasma. Mean IGF-I level in plasma showed a negative correlation with PD and CAL (p < 0.05) in both groups. The levels of IGF-I and IGFBP-3 in GCF seemed to be negatively correlated with BOP in the test group (p < 0.05). Conclusions: The difference in the level of IGF-I and IGFBP-3 between AgP and healthy subjects was not significant. Further studies that explain the mechanism of the protective role of IGF-I with more samples are needed.Keywords: aggressive periodontitis, pathogenesis, insulin-like growth factor, insulin-like growth factor binding protein
Procedia PDF Downloads 2107635 Study of the Clogging of Localized Irrigation Pipelines at the Agricultural Region of Agadir
Authors: Ali Driouiche, Abdallah Hadfi
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During this work on scaling phenomenon observed in the irrigation water pipes in the agricultural region of Greater Agadir, a follow-up was carried out during a year of the physico-chemical quality of these waters. Sampling was conducted from 120 sampling points, well distributed in the study area and involved 120 water samples. The parameters measured for each sample are temperature, pH, conductivity, total hardness and the concentrations of the ions HCO₃₋, Ca²⁺, Mg²⁺, Na⁺, K⁺, SO₄₋, NO₃₋, Cl₋ and OH₋. Indeed, the monitoring of the physico-chemical quality shows that the total hardness varies between 20 and 65 °F and the complete alkalimetric title varies from 14 °F to 42 °F. For the kinetic study of the scaling power, an object of this work, 6 samples which have high hardness were selected from the 120 samples analyzed. This study was carried out using the controlled degassing method Laboratoire de Chimie et de Génie de l’Environnement (LCGE) where it was developed) and showed that the studied waters are calcifying. The germination time Tg varies between 16 and 34 minutes. The highlighting of new scale inhibitors to prevent the formation of scale in the pipelines of the agricultural sector of Greater Agadir will also be discussed.Keywords: agadir, clogging pipes, localized irrigation, scaling power
Procedia PDF Downloads 1217634 Defective Autophagy Leads to the Resistance to PP2 in ATG5 Knockout Cells Generated by CRISPR-Cas9 Endonuclease
Authors: Sung-Hee Hwang, Michael Lee
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Upregulated Src activity has been implicated in a variety of cancers. Thus, Src family tyrosine kinase (SFK) inhibitors are often effective cancer treatments. Here, we investigate the role of autophagy in ATG5 knockout cell lines generated by the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas mediated genome editing. The CRISPR-associated protein Cas9 is an RNA-guided DNA endonuclease that uses RNA–DNA complementarity to identify target sites for sequence specific double-stranded DNA (dsDNA) cleavage. Interestingly, ATG5 KO cells clearly showed a greater proliferation rate than WT NIH 3T3 cells, implying that autophagy induction is cytotoxic. Also, the clonogenic survival of ATG5 KO cells was greater than WT cells. The MTT assay revealed that the cytotoxic effect of PP2 was weaker on ATG5 knockout cells than that WT cells. The conversion of non-autophagic LC3-I to autophagic LC3-II and RT-PCR confirmed the functional gene knockout. Furthermore, Cyto-ID autophagy assay also revealed that PP2 failed to induce autophagy in ATG5 knockout cells. Together, our findings suggest that the resistance to PP2 in ATG5 knockout cells is associated with defective autophagy.Keywords: ATG5 knockout, Autophagy, CRISPR/Cas9, PP2
Procedia PDF Downloads 3477633 Determination of Gross Alpha and Gross Beta Activity in Water Samples by iSolo Alpha/Beta Counting System
Authors: Thiwanka Weerakkody, Lakmali Handagiripathira, Poshitha Dabare, Thisari Guruge
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The determination of gross alpha and beta activity in water is important in a wide array of environmental studies and these parameters are considered in international legislations on the quality of water. This technique is commonly applied as screening method in radioecology, environmental monitoring, industrial applications, etc. Measuring of Gross Alpha and Beta emitters by using iSolo alpha beta counting system is an adequate nuclear technique to assess radioactivity levels in natural and waste water samples due to its simplicity and low cost compared with the other methods. Twelve water samples (Six samples of commercially available bottled drinking water and six samples of industrial waste water) were measured by standard method EPA 900.0 consisting of the gas-less, firm wear based, single sample, manual iSolo alpha beta counter (Model: SOLO300G) with solid state silicon PIPS detector. Am-241 and Sr90/ Y90 calibration standards were used to calibrate the detector. The minimum detectable activities are 2.32mBq/L and 406mBq/L, for alpha and beta activity, respectively. Each of the 2L water samples was evaporated (at low heat) to a small volume and transferred into 50mm stainless steel counting planchet evenly (for homogenization) and heated by IR lamp and the constant weighted residue was obtained. Then the samples were counted for gross alpha and beta. Sample density on the planchet area was maintained below 5mg/cm. Large quantities of solid wastes sludges and waste water are generated every year due to various industries. This water can be reused for different applications. Therefore implementation of water treatment plants and measuring water quality parameters in industrial waste water discharge is very important before releasing them into the environment. This waste may contain different types of pollutants, including radioactive substances. All these measured waste water samples having gross alpha and beta activities, lower than the maximum tolerance limits for industrial waste water discharge of industrial waste in to inland surface water, that is 10-9µCi/mL and 10-8µCi/mL for gross alpha and beta respectively (National Environmental Act, No. 47 of 1980). This is according to extraordinary gazette of the democratic socialist republic of Sri Lanka in February 2008. The measured water samples were below the recommended radioactivity levels and do not pose any radiological hazard when releasing the environment. Drinking water is an essential requirement of life. All the drinking water samples were below the permissible levels of 0.5Bq/L for gross alpha activity and 1Bq/L for gross beta activity. The values have been proposed by World Health Organization in 2011; therefore the water is acceptable for consumption of humans without any further clarification with respect to their radioactivity. As these screening levels are very low, the individual dose criterion (IDC) would usually not be exceeded (0.1mSv y⁻¹). IDC is a criterion for evaluating health risks from long term exposure to radionuclides in drinking water. Recommended level of 0.1mSv/y expressed a very low level of health risk. This monitoring work will be continued further for environmental protection purposes.Keywords: drinking water, gross alpha, gross beta, waste water
Procedia PDF Downloads 1987632 Degradation Mechanism of Automotive Refinish Coatings Exposed to Biological Substances: The Role of Cross-Linking Density
Authors: M. Mahdavi, M. Mohseni, R. Rafiei, H. Yari
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Environmental factors can deteriorate the automotive coatings significantly. Such as UV radiations, humidity, hot-cold shock and destructive chemical compounds. Furthermore, some natural materials such as bird droppings and tree gums have the potential to degrade the coatings as well. The present work aims to study the mechanism of degradation for two automotive refinish coating (PU based) systems exposed to two types of biological materials, i.e. Arabic gum and the simulated bird dropping, pancreatin. To reach this goal, effects of these biological materials on surface properties and appearance were studied using different techniques including digital camera, FT-IR spectroscopy, optical microscopy, and gloss measurements. In addition, the thermo-mechanical behavior of coatings was examined by DMTA. It was found that cross-linking had a crucial role on the biological resistance of clear coat. The higher cross-linking enhanced biological resistance.Keywords: refinish clear coat, pancreatin, Arabic gum, cross-linking, biological degradation
Procedia PDF Downloads 3687631 Effect of Two Different Method for Juice Processing on the Anthocyanins and Polyphenolics of Blueberry (Vaccinium corymbosum)
Authors: Onur Ercan, Buket Askin, Erdogan Kucukoner
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Blueberry (Vaccinium corymbosum, bluegold) has become popular beverage due to their nutritional values such as vitamins, minerals, and antioxidants. In the study, the effects of pressing, mashing, enzymatic treatment, and pasteurization on anthocyanins, colour, and polyphenolics of blueberry juice (BJ) were studied. The blueberry juice (BJ) was produced with two different methods that direct juice extraction (DJE) and mash treatment process (MTP) were applied. After crude blueberry juice (CBJ) production, the samples were first treated with commercial enzymes [Novoferm-61 (Novozymes A/S) (2–10 mL/L)], to break down the hydrocolloid polysaccharides, mainly pectin and starch. The enzymes were added at various concentrations. The highest transmittance (%) was obtained for Novoferm-61 at a concentration of 2 mL/L was 66.53%. After enzymatic treatment, clarification trials were applied to the enzymatically treated BJs with adding various amounts of bentonite (10%, w/v), gelatin (1%, w/v) and kiselsol (15%, v/v). The turbidities of the clarified samples were then determined. However, there was no significant differences between transmittances (%) for samples. For that, only enzymatic treatment was applied to the blueberry juice processing (DDBJ, depectinized direct blueberry juice). Based on initial pressing process made to evaluate press function, it was determined that pressing fresh blueberries with no other processing did not render adequate juice due to lack of liquefaction. Therefore, the blueberries were mash into small pieces (3 mm) and then enzymatic treatments and clarification trials were performed. Finally, both BJ samples were pasteurized. Compositional analyses, colour properties, polyphenols and antioxidant properties were compared. Enzymatic treatment caused significant reductions in ACN content (30%) in Direct Blueberry Juice Processing (DBJ), while there was a significant increasing in Mash Treatment Processing (MTP). Overall anthocyanin levels were higher intreated samples after each processing step in MTP samples, but polyphenolic levels were slightly higher for both processes (DBJ and MTP). There was a reduction for ACNs and polyphenolics only after pasteurization. It has a result that the methods for tried to blueberry juice is suitable into obtain fresh juice. In addition, we examined fruit juice during processing stages; anthocyanin, phenolic substance content and antioxidant activity are higher, and yield is higher in fruit juice compared to DBJ method in MTP method, the MTP method should be preferred in processing juice of blueberry into fruit juice.Keywords: anthocyanins, blueberry, depectinization, polyphenols
Procedia PDF Downloads 937630 Engineering Analysis for Fire Safety Using Computational Fluid Dynamic (CFD)
Authors: Munirajulu M, Srikanth Modem
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A large cricket stadium with the capacity to accommodate several thousands of spectators has the seating arena consisting of a two-tier arrangement with an upper and a lower bowl and an intermediate concourse podium level for pedestrian movement to access the bowls. The uniqueness of the stadium is that spectators can have an unobstructed view from all around the podium towards the field of play. Upper and lower bowls are connected by stairs. The stairs landing is a precast slab supported by cantilevered steel beams. These steel beams are fixed to precast columns supporting the stadium structure. The stair slabs are precast concrete supported on a landing slab and cantilevered steel beams. During an event of a fire at podium level between two staircases, fire resistance of steel beams is very critical to life safety. If the steel beam loses its strength due to lack of fire resistance, it will be weak in supporting stair slabs and may lead to a hazard in evacuating occupants from the upper bowl to the lower bowl. In this study, to ascertain fire rating and life safety, a performance-based design using CFD analysis is used to evaluate the steel beams' fire resistance. A fire size of 3.5 MW (convective heat output of fire) with a wind speed of 2.57 m/s is considered for fire and smoke simulation. CFD results show that the smoke temperature near the staircase/ around the staircase does not exceed 1500 C for the fire duration considered. The surface temperature of cantilevered steel beams is found to be less than or equal to 1500 C. Since this temperature is much less than the critical failure temperature of steel (5200 C), it is concluded that the design of structural steel supports on the staircase is adequate and does not need additional fire protection such as fire-resistant coating. CFD analysis provided an engineering basis for the performance-based design of steel structural elements and an opportunity to optimize fire protection requirements. Thus, performance-based design using CFD modeling and simulation of fire and smoke is an innovative way to evaluate fire rating requirements, ascertain life safety and optimize the design with regard to fire protection on structural steel elements.Keywords: fire resistance, life safety, performance-based design, CFD analysis
Procedia PDF Downloads 1927629 Pesticide Residue Determination on Cumin Plant (Nigella orientalis L.) Grown through Agricultural Practices with LC-MS/MS and GC-MS
Authors: Nilda Ersoy, Sevinç Şener, Ayşe Yalçın Elidemir, Ebru Evcil, Ergün Döğen
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In this study, pesticide residues were investigated in black cumin (Nigella orientalis L.) seeds which grown in Turkey. GC-MS and LC-MS/MS analytical instruments are used in high precision, when determining residue limits. A total of 100 pesticide active ingredients in LC-MS/MS devices have been performed in Nigella orientalis L. seeds samples. Moreover, for same aim, 103 pesticide active ingredients were analyzed in GC-MS. This study conducted in 2012 and 2013. Samples residues were not found in detectable levels for two years.Keywords: pesticide, residue, black cumin, Nigella orientalis L.
Procedia PDF Downloads 3367628 Pale, Soft, Exudative (PSE) Turkey Meat in a Brazilian Commercial Processing Plant
Authors: Danielle C. B. Honorato, Rafael H. Carvalho, Adriana L. Soares, Ana Paula F. R. L. Bracarense, Paulo D. Guarnieri, Massami Shimokomaki, Elza I. Ida
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Over the past decade, the Brazilian production of turkey meat increased by more than 50%, indicating that the turkey meat is considered a great potential for the Brazilian economy contributing to the growth of agribusiness at the marketing international scenario. However, significant color changes may occur during its processing leading to the pale, soft and exudative (PSE) appearance on the surface of breast meat due to the low water holding capacity (WHC). Changes in PSE meat functional properties occur due to the myofibrils proteins denaturation caused by a rapid postmortem glycolysis resulting in a rapid pH decline while the carcass temperature is still warm. The aim of this study was to analyze the physical, chemical and histological characteristics of PSE turkey meat obtained from a Brazilian commercial processing plant. The turkey breasts samples were collected (n=64) at the processing line and classified as PSE at L* ≥ 53 value. The pH was also analyzed after L* measurement. In sequence, PSE meat samples were evaluated for WHC, cooking loss (CL), shear force (SF), myofibril fragmentation index (MFI), protein denaturation (PD) and histological evaluation. The abnormal color samples presented lower pH values, 16% lower fiber diameter, 11% lower SF and 2% lower WHC than those classified as normal. The CL, PD and MFI were, respectively, 9%, 18% and 4% higher in PSE samples. The Pearson correlation between the L* values and CL, PD and MFI was positive, while that SF and pH values presented negative correlation. Under light microscopy, a shrinking of PSE muscle cell diameter was approximately 16% shorter in relation to normal samples and an extracellular enlargement of endomysium and perimysium sheaths as the consequence of higher water contents lost as observed previously by lower WHC values. Thus, the results showed that PSE turkey breast meat presented significant changes in their physical, chemical and histological characteristics that may impair its functional properties.Keywords: functional properties, histological evaluation, meat quality, PSE
Procedia PDF Downloads 4607627 MicroRNA Differential Profiling in Hepatitis C Patients Undergoing Major Surgeries: Propofol versus Sevoflurane Anesthesia
Authors: Hala Demerdash, Ola M. Zanaty, Emad Eldin Arida
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Background: This study investigated the micoRNA expression changes induced by Sevoflurane and Propofol and their effects on liver functions. Patients and methods: The study was designed as randomized controlled study, carried out on 200 adult patients, scheduled for major surgeries under general anesthesia (GA). Patients were randomly divided into four groups; groups SC and PC included chronic hepatitis C (CHC) patients where SC group are patients receiving Sevoflurane, and PC group are patients receiving Propofol anesthesia. While S and P groups included non- hepatitis patients; S group are patients receiving Sevoflurane and P group are patients receiving Propofol. Anesthesia in Group S and SC patients was maintained by sevoflurane, while anesthesia in Group P and PC patients was maintained by propofol infusion. Blood samples were analyzed for PT, PTT and liver enzymes. Serum samples were analyzed for microRNA before and after surgery. Results: Results show miRNA-122 and miRNA-21 were absent in serum of S and P groups in pre-operative samples. However, they were expressed in SC and PC groups. In post-operative samples; miRNA-122 revealed an increased expression in all groups; with more exaggerated response in SC group. On the other hand miRNA-21 revealed increased expression in both SC and PC groups; a slight expression in S group with absent expression in P group. There was a post-operative negative correlation between miR-122 and ALT (r=-0.46) in SC group and (r=-0.411) in PC group and positive correlation between ALT and miR-21 (r=0.335) in SC group and (r=0.379) in PC group. The amount of blood loss was positively correlated with miR-122 (r=0.366) in SC group and (r=0.384) in PC group. Conclusion: Propofol anesthesia is safer than Sevoflurane anesthesia in patients with CHC. Sevoflurane and Propofol anesthesia affect miRNA expression in both CHC and non-hepatitis patients.Keywords: anesthesia, chronic hepatitis C, micoRNA, propofol, sevoflurane
Procedia PDF Downloads 3417626 Mechanical Characterization and Metallography of Sintered Aluminium-Titanium Diboride Metal Matrix Composite
Authors: Sai Harshini Irigineni, Suresh Kumar Reddy Narala
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The industrial applicability of aluminium metal matrix composites (AMMCs) has been rapidly growing due to their exceptional materials traits such as low weight, high strength, excellent thermal performance, and corrosion resistance. The increasing demand for AMMCs in automobile, aviation, aerospace and defence ventures has opened up windows of opportunity for the development of processing methods that facilitate low-cost production of AMMCs with superior properties. In the present work, owing to its economy, efficiency, and suitability, powder metallurgy (P/M) technique was employed to develop AMMCs with pure aluminium as matrix material and titanium diboride (TiB₂) as reinforcement. AMMC samples with different weight compositions (Al-0.1%TiB₂, Al-5%TiB₂, Al-10%TiB₂, and Al-15% TiB₂) were prepared through hot press compacting followed by traditional sintering. The developed AMMC was subjected to metallographic studies and mechanical characterization. Experimental evidences show significant improvement in mechanical properties such as tensile strength, hardness with increasing reinforcement content. The current study demonstrates the superiority of AMMCs over conventional metals and alloys and the results obtained may be of immense in material selection for different structural applications.Keywords: AMMCs, mechanical characterization, powder metallurgy, TiB₂
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