Search results for: Esther Lorrayne M. Pereira

Authors: Esther Lorrayne M. Pereira, Adriana S. M. Batista, Fabíola A. S. Ribeiro, Adelina P. Santos, Luiz O. Faria

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In this work we have prepared nanocomposites made by mixing Poli (vinilidene fluoride) (PVDF), zirconium oxide (ZrO₂) and multi–walled carbon nanotubes (MWCNTs) aiming to find dosimetric properties for applications in high dose dosimetry. The samples were irradiated with a Co-60 source at constant dose rate (16.7 kGy/h), with doses ranging from 100 to 2750 kGy. The UV-Vis and FTIR spectrophotometry have been used to monitor the appearing of C=C conjugated bonds and radio-oxidation of carbon (C=O). FTIR spectrometry has that the absorbance intensities at 1715 cm⁻¹ and 1730 cm⁻¹ can be used for high dosimetry purposes for gamma doses ranging from 500 to 2750 kGy. In this range, it is possible to observe a linear relationship between Abs & Dose. Fading of signal was evaluated for one month and reproducibility in 2000 kGy dose. Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) was used for evaluated the dispersion ZrO₂ and MWCNT in the matrix of the PVDF.

Keywords: polymer, composite, high dose dosimetry, PVDF/ZrO₂/MWCNT

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Authors: Esther Lorrayne M. Pereira, Adriana Souza M. Batista, Fabíola A. S. Ribeiro, Adelina P. Santos, Clascídia A. Furtado, Luiz O. Faria

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The combination of multi–walled carbon nanotubes (MWCNTs) with polymers offers an attractive route to reinforce the macromolecular compounds as well as the introduction of new properties based on morphological modifications or electronic interactions between the two constituents. As they are only a few nanometers in dimension, it offers ultra-large interfacial area per volume between the nano-element and polymer matrix. Nevertheless, the use of MWCNTs as a rough material in different applications has been largely limited by their poor processability, insolubility, and infusibility. Studies concerning the nanofiller reinforced polymer composites are justified in an attempt to overcome these limitations. This work presents one preliminary study of MWCNTs dispersion into the PVDF homopolymer. For preparation, the composite components were diluted in n,n-dimethylacetamide (DMAc) with mechanical agitation assistance. After complete dilution, followed by slow evaporation of the solvent at 60°C, the samples were dried. Films of about 80 μm were obtained. FTIR and UV-Vis spectroscopic techniques were used to characterize the nanocomposites. The appearance of absorption bands in the FTIR spectra of nanofilled samples, when compared to the spectrum of pristine PVDF samples, are discussed and compared with the UV-Vis measurements.

Keywords: composites materials, FTIR, MWNTs, PVDF, UV-vis

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Authors: W. S. Lawal, T. A. Akande

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Four (4) different methods were employed to detoxified jatropha caucas, they are physical method (if include soaking and drying) chemical method (use of methylated spirit, hexane and methene) biological method,(use of Aspergillus niger and Sunday for 7 days and then baccillus lichifarming) and finally combined method (combination of all these methods). Phobol esther andysis was carried out after the detoxification and was found that combined method is better off (P>0.05). 100 broiler birds was used to further test the effect of detoxified Jatropha by combined method, 50 birds for Jatropha made feed at 10 birds per treatment and was replicated five times, this was also repeated for another 50 birds fed conventional feed, Jatropha made feed was compranded at 8% inclusion level. At the end of the 8th weeks, 8 birds were sacrificed each from each treatment and one bird each was fry, roast, boil and grilled from both conventional and Jatropha fed birds and panelist were served for evaluation. It was found that feeding Jatropha to poultry birds has no effect on the taste of the meat.

Keywords: phobol esther, inclusion level, tolerance level, Jatropha carcass

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Authors: Nivaldo Ferreira do Nascimento, Matheus Pereira-Santos, Nycolas Levy-Pereira, José Augusto Senhorini, George Shigueki Yasui, Laura Satiko Okada Nakaghi

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Tetraploid individuals, which could produce diploid gametes, can be used for production of 100% triploid fish. Therefore, the aim of this study was to develop a tetraploidization protocol for A. altiparanae. We tested the effect of heat shock (40 °C; 2 min) at 16, 18, 20, 22, 24 and 26 minutes post fertilization (mpf). Untreated eggs were used as control. After hatching, ploidy status of the larvae was checked by flow cytometry. No difference were observed for the hatching rate between all treatments (P = 0.5974). However, we observed an increase in the larval abnormality in the heat shock treatments, in special at 22 (82.17 ± 6.66%) 24 (78.31 ±7.28%) and 26 mpf (79.01 ± 7.85%) in comparison with the control group (12.87 ± 4.46%). No tetraploid was observed at 16 and 18 mpf. The higher number of tetraploid individuals (52/55) was observed at 26 mpf. Our results showed that high percentages of tetraploids are obtained by heat shock (40°C; 2min) at 26 mpf, which could enable the mass production of triploid individuals in A. altiparanae.

Keywords: chromosome manipulation, polyploidy, flow cytometry, tetraploidization

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Authors: W. S. Lawal, T. Akande

Abstract:

Abstract— Four (4) difference methods were employed to detoxify Jatropha carcas, they were physical method (it include soaking and sun drying) Chemical (the use of methylated sprit, hexane and methane). Biological (the use of Aspergillus niger and then sundry for 7days and then Bacillus lichiformis) and Combined method (the combination of chemical and biological methods). Phobol esther analysis was carried out after the detoxification methods and it was found that the combined method is better off (P<0.05). Detoxified Jatropha from each of this methods was sundry and grinded for easy inclusion into poultry feed, detoxified jatropha was included at 0%, 0.5%, 1%, 2%, 3%, 4%, and 5% but the combined method was increased up to 7% because the birds were able to tolerate it, the 0% was the control experiment. 405 day old broiler chicks was used to test the effect of detoxified Jatropha carcas on their performance, there are 5birds per treatment and there are 3 replicates, the experiment lasted for 8weeks,highest number of mortality was obtained in physical method, birds in chemical method tolerated up to 3% Jatropha carcas, biological method is better, as birds there were comfortable at 5% but the best of them is combined method the birds did very well at 7% as there were less mortality and highest weight gain was achieved here (P<0.05) and it was recommended.

Keywords: phobol esther, inclusion level, tolerance level, Jatropha carcas

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Authors: Diana Fajardo, Sebastián Ortiz, Oscar Herrera, Angélica Santis

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Currently, in Colombia is arising a problem related to collecting used lubricant oils which are generated by the increment of the vehicle fleet. This situation does not allow a proper disposal of this type of waste, which in turn results in a negative impact on the environment. Therefore, through the comparative analysis of various heuristics, the best solution to the VRP (Vehicle Routing Problem) was selected by comparing costs and times for the collection of used lubricant oils in the city of Pereira, Colombia; since there is no presence of management companies engaged in the direct administration of the collection of this pollutant. To achieve this aim, six proposals of through methods of solution of two phases were discussed. First, the assignment of the group of generator points of the residue was made (previously identified). Proposals one and four of through methods are based on the closeness of points. The proposals two and five are using the scanning method and the proposals three and six are considering the restriction of the capacity of collection vehicle. Subsequently, the routes were developed - in the first three proposals by the Clarke and Wright's savings algorithm and in the following proposals by the Traveling Salesman optimization mathematical model. After applying techniques, a comparative analysis of the results was performed and it was determined which of the proposals presented the most optimal values in terms of the distance, cost and travel time.

Keywords: Heuristics, optimization Model, savings algorithm, used vehicular oil, V.R.P.

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Authors: Sílvia Pereira Mello, Eliane Rodrigues, Maria de Lourdes Andrade, Marcelo Pereira, Giselle Dias, Jose Seixas Filho

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Frog meat is a highly digestible food and its use is recommended in diets aimed at fighting cholesterol, obesity, and arterial hypertension, as well as for treating gastrointestinal disorders. In this study, the soups were developed with frog meat in addition to other ingredients which did not present allergenic potential. The carcasses of the thawed frogs went through bleaching and deboning, and other ingredients (vegetables and condiments) were then added to the separated meat. After the process of cooking, the soups were cooled and later on frozen at -40° C for 3 hours and then taken to the LS 3000 B lyophilizer for 24 hours. The soups were submitted to microbiological analysis: enumeration of total coliforms and Bacillus cereus; identification of coagulase positive Staphylococcus; isolation and identification of Salmonella spp.; and physical-chemical analysis; application of micro-Kjeldahl method for protein, Soxhlet method for lipids, use of a heating chamber at 105ºC for moisture, incineration method (500-550°C) for ash, and Decagon's Pawkit equipment for determining water activity. Acceptance test was performed with 50 elderly people, all between 60 and 85 years of age. The degree of acceptance was demonstrated using a seven points structured hedonic scale in which the taster expressed their impression towards the product. Results of the microbiological analysis showed that all samples met the standards established by the National Health Surveillance Agency of Brazil (ANVISA). Results of the acceptance test indicated that all the soups were accepted considering overall impression and intended consumption. In addition to its excellent nutritional quality, the dehydrated soups made with frog meat are presented as a solution for consumers due to convenience in preparation, consumption and storage.

Keywords: bacteriological quality, lithobates catesbeianus, instant soup, proximate composition, sensory analysis

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Authors: Juliana Pereira Tigre

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In the current critical debate on the process of globalization, on the one hand, arises the accusation that neoliberalism standardizes the so-called American way of life on the cultures of the world, operating as a system of subtle domination, expropriating and incorporating the other. On the other hand, it is defended that neoliberalism begins its career of political and economic order as a sensitive conception to the otherness, imposing itself at present due to its peaceful management of pluralism and defense of individual freedom. In this sense, this paper aims to discuss the extent to which the neoliberalism and the otherness converge or diverge in contemporaneity and the guiding principles of globalization.

Keywords: otherness, globalization, neoliberalism, social sciences

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Authors: Diego De Almeida Pereira, Diana Borchenko

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Artificial neural networks are used for many applications as they are able to learn complex nonlinear relationships between input and output data. As the number of neurons and layers in a neural network increases, it is possible to represent more complex behaviors. The present study proposes that artificial neural networks are a valuable tool for architecture and engineering professionals concerned with understanding how buildings influence human and social well-being based on theories of environmental psychology.

Keywords: environmental psychology, architecture, neural networks, human and social well-being

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Authors: Esther Ushike Akashie

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No matter who you are, where you are from and irrespective of age and gender, there is a universal need for power and energy. Every year, this need grows even more urgent the more scientific and technological inventions advance. Due to this fact, we find that majority of the research related to energy and power has been focused on finding new and innovative ways to produce power. Furthermore, we observe that because of the environmental state of our world today and the impact of climate change, one of the most explored routes of study has been the use of renewable energies. In this paper, we will be looking at one of the oldest forms of renewable energy, hydroelectric energy. First off, an overview of its history, sources, technical aspects, and applications will be evaluated. After which, we will then proceed to understand the main benefits and drawbacks of this form of renewable energy and offer insights on how it can be better utilized in our world today.

Keywords: hydropower, hydroelectric energy, advantages, disadvantages

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Authors: Cristina Núñez, Rufina Bastida, Elena Labisbal, Alejandro Macías, María T. Pereira, José M. Vila

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A highly selective quinoline-based fluorescent sensor L was designed in order to functionalize gold nanoparticles (GNPs@L). The cytotoxicity of compound L and GNPs@L on the MCF-7 breast cancer cells was explored and it was observed that L and GNPs@L compounds induced apoptosis in MCF-7 cancer cells. The cellular uptake of the hybrid system GNPs@L was studied using confocal laser scanning microscopy (CLSM).

Keywords: cytotoxicity, fluorescent probes, nanoparticles, quinoline

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Authors: Esther, Queeny

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The main goal of this paper is to reflect on the overwhelming, rich folklore of Telugu people through their proverbs, which are assumed to be in a state of endangerment. In order to prove the statement made that the proverbs in Telugu are endangered, we have to delve deeper. We hardly found two or three papers related to Telugu proverbs. So, though the process was weary of sorting out the different proverbs in Telugu, to translate them etc. we found it necessary to do a survey in the form of a questionnaire and draw conclusions so that we could address this issue to the readers. We began with a basic assumption that the older generation may have a wider knowledge of their folklore when compared to the younger generation. The results obtained are quite remarkable, which strengthened our assumptions. Statistical analysis was adopted for quantitative analysis. Through this paper, we hope to kindle cultural awareness among the youngsters regarding the use of one’s own mother tongue.

Keywords: sociolinguistics, Telugu proverbs, folklore, endangerment

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Authors: Agarana Michael C., Akinlabi Esther T., Pule Kholopane

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Innovation in manufacturing process technologies and associated product design affects the prospects for manufacturing today and in near future. In this study some theoretical methods, useful as tools in advanced manufacturing, are considered. In particular, some basic Mathematical, Operational Research, Heuristic, and Statistical techniques are discussed. These techniques/methods are very handy in many areas of advanced manufacturing processes, including process planning optimization, modelling and analysis. Generally the production rate requires the application of Mathematical methods. The Emerging Trends Processes in Advanced Manufacturing can be enhanced by using Mathematical Modelling and Optimization techniques.

Keywords: mathematical modelling, optimization, emerging trends, advanced manufacturing

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Authors: Esther Moraleda Sepúlveda, Soraya Delgado Matute, Paula Salido Escudero, Raquel Mimoso García, M Cristina Alcón Lancho

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Although there is some consensus when it comes to establishing the lexicon as one of the strengths of language in people with Down Syndrome (DS), little is known about its evolution throughout development and changes based on age. The objective of this study was to find out if there are differences in receptive vocabulary between adolescence and adulthood. In this research, 30 people with DS between 11 and 40 years old, divided into two age ranges (11-18; 19 - 30) and matched in mental age, were evaluated through the Peabody Vocabulary Test. The results show significant differences between both groups in favor of the group with the oldest chronological age and a direct correlation between chronological age and receptive vocabulary development, regardless of mental age. These data support the natural evolution of the passive lexicon in people with DS.

Keywords: down syndrome, language, receptive vocabulary, adolescents, adults

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Authors: Ramon Sancibrian, Carlos Redondo-Figuero, Maria C. Gutierrez-Diez, Esther G. Sarabia, Maria A. Benito-Gonzalez, Jose C. Manuel-Palazuelos

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In this paper, the design and evaluation of a handle for laparoscopic surgery is presented. The design of the handle is based on ergonomic principles and tries to avoid awkward postures for surgeons. The handle combines the so-called power-grip and accurate-grip in order to provide strength and accuracy in the performance of surgery. The handle is tested using both objective and subjective approaches. The objective approach uses motion capture techniques to obtain the angles of forearm, arm, wrist and hand. The muscular effort is obtained with electromyography electrodes. On the other hand, a subjective survey has been carried out using questionnaires. Results confirm that the handle is preferred by the majority of the surgeons.

Keywords: laparoscopic surgery, ergonomics, mechanical design, biomechanics

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Authors: Carlos Henrique Rodrigues de Oliveira, Luis Carlos Costa Fonseca, Caio de Castro Torres, Daniel Gusmão Pereira, Luiz Ricardo Souza Ripardo, Magno Castro Moraes, Ana Paula Ferreira Costa, Luiz Carlos Chaves Lima Junior, Aurelianny Almeida da Cunha

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VoIP University is a communication solution based on the IP protocol. This solution was proposed to modernize and save on communication, which required the development of Android, iOS, and Windows applications and a web service server. This solution allows integration with management system databases to create and manage a list of user extensions. VoIP University was deployed in a university, and a financial analysis revealed that annual spending on telephone bills decreased by more than 97 %.

Keywords: VoIP eTec, VoIP UEMA, VoIP University, VoIP Valen

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Authors: Stephen A. Akinlabi, Esther T. Akinlabi

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The drip irrigation system is one of the important areas that affect the livelihood of farmers directly. The use of drip irrigation system has been the most efficient system compared to the other types of irrigations systems because the drip irrigation helps to save water and increase the productivity of crops. But like any other system, it can be considered inefficient when the filters and the emitters get clogged while in operation. The efficiency of the entire system is reduced when the emitters are clogged and blocked. This consequently impact and affect the farm operations which may result in scarcity of farm products and increase the demand. This design work focuses on how to overcome some of the challenges affecting drip irrigation system through the design of an efficient filtration and flushing system.

Keywords: drip irrigation system, filters, soil texture, mechanical engineering design, analysis

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Authors: Javiera Espinosa, Patricia López, Noelia Santos, Nadia Loro, Esther Moraleda

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In recent years, there has been a notable increase in the number of investigations that establish that Down Syndrome and Autism Spectrum Disorder are diagnoses that can coexist together. However, there are also many studies that consider that both diagnoses present neuropsychological, linguistic and adaptive characteristics with a totally different profile. The objective of this research is to question whether there really can be a profile that encompasses both disorders or if they can be incompatible with each other. To this end, a review of the scientific literature of recent years has been carried out. The results indicate that the two lines collect opposite approaches. On the one hand, there is research that supports the increase in comorbidity between Down Syndrome and Autism Spectrum Disorder, and on the other hand, many investigations show a totally different general development profile between the two. The discussion focuses on discussing both lines of work and on proposing future lines of research in this regard.

Keywords: disability, language, speech, down syndrome

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Authors: Gredson Keif Souza, Nehemias Curvelo Pereira

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Kernel oil from Macaúba is an important source of essential fatty acids. Thus, a new knowledge of the oil of this species could be used in new applications, such as pharmaceutical drugs based in the manufacture of cosmetics, and in various industrial processes. The aim of this study was to characterize the kernel oil of macaúba (Acrocomia Totai) at different times of their maturation. The physico-chemical characteristics were determined in accordance with the official analytical methods of oils and fats. It was determined the content of water and lipids in kernel, saponification value, acid value, water content in the oil, viscosity, density, composition in fatty acids by gas chromatography and molar mass. The results submitted to Tukey test for significant value to 5%. Found for the unripe fruits values superior to unsaturated fatty acids.

Keywords: extraction, characterization, kernel oil, acrocomia totai

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Authors: Hendrick Maxil Zárate Rocha, Ricardo da Silva Pereira, Manoel Fernandes Martins Nogueira, Carlos R. Pereira Belchior, Maria Emilia de Lima Tostes

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This study investigates experimentally the effects of hydrogen addition in the intake manifold of a diesel generator operating with a 7% biodiesel-diesel oil blend (B7). An experimental apparatus setup was used to conduct performance and emissions tests in a single cylinder, air cooled diesel engine. This setup consisted of a generator set connected to a wirewound resistor load bank that was used to vary engine load. In addition, a flowmeter was used to determine hydrogen volumetric flowrate and a digital anemometer coupled with an air box to measure air flowrate. Furthermore, a digital precision electronic scale was used to measure engine fuel consumption and a gas analyzer was used to determine exhaust gas composition and exhaust gas temperature. A thermopar was installed near the exhaust collection to measure cylinder temperature. In-cylinder pressure was measured using an AVL Indumicro data acquisition system with a piezoelectric pressure sensor. An AVL optical encoder was installed in the crankshaft and synchronized with in-cylinder pressure in real time. The experimental procedure consisted of injecting hydrogen into the engine intake manifold at different mass concentrations of 2,6,8 and 10% of total fuel mass (B7 + hydrogen), which represented energy fractions of 5,15, 20 and 24% of total fuel energy respectively. Due to hydrogen addition, the total amount of fuel energy introduced increased and the generators fuel injection governor prevented any increases of engine speed. Several conclusions can be stated from the test results. A reduction in specific fuel consumption as a function of hydrogen concentration increase was noted. Likewise, carbon dioxide emissions (CO2), carbon monoxide (CO) and unburned hydrocarbons (HC) decreased as hydrogen concentration increased. On the other hand, nitrogen oxides emissions (NOx) increased due to average temperatures inside the cylinder being higher. There was also an increase in peak cylinder pressure and heat release rate inside the cylinder, since the fuel ignition delay was smaller due to hydrogen content increase. All this indicates that hydrogen promotes faster combustion and higher heat release rates and can be an important additive to all kind of fuels used in diesel generators.

Keywords: diesel engine, hydrogen, dual fuel, combustion analysis, performance, emissions

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Authors: Emmanuel Ogundimu, Esther Akinlabi, Mutiu Erinosho

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In this research, studies were done on the material characterization of type 304 austenitic stainless steel weld produced by TIG (Tungsten Inert Gas) and MIG (Metal Inert Gas) welding processes. This research is aimed to establish optimized process parameters that will result in a defect-free weld joint, homogenous distribution of the iron (Fe), chromium (Cr) and nickel (Ni) was observed at the welded joint of all the six samples. The welded sample produced at the current of 170 A by TIG welding process had the highest ultimate tensile strength (UTS) value of 621 MPa at the welds zone, and the welded sample produced by MIG process at the welding current of 150 A had the lowest UTS value of 568 MPa. However, it was established that TIG welding process is more appropriate for the welding of type 304 austenitic stainless steel compared to the MIG welding process.

Keywords: microhardness, microstructure, tensile, MIG welding, process, tensile, shear stress TIG welding, TIG-MIG welding

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Authors: Elena Jiménez Lidueña, Noelia Santos Muriel, Patricia López Resa, Noelia Pulido García, Esther Moraleda Sepúlveda

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In recent years, there has been a notable increase in the number of investigations that establish that Down Syndrome and Autism Spectrum Disorder are diagnoses that can coexist together. However, there are also many studies that consider that both diagnoses present neuropsychological, linguistic and adaptive characteristics with a totally different profiles. The objective of this research is to question whether there really can be a profile that encompasses both disorders or if they can be incompatible with each other. To this end, a review of the scientific literature of recent years has been carried out. The results indicate that the two lines collect opposite approaches. On the one hand, there is research that supports the increase in comorbidity between Down Syndrome and Autism Spectrum Disorder and, on the other hand, shows a totally different general development profile between the two. The discussion focuses on discussing both lines of work and on proposing future lines of research in this regard.

Keywords: Down Syndrome, Autism, comorbidity, linguistic

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Authors: Juliana V. Pereira, Adriana S. M. Batista, Jefferson P. Nascimento, Clascídia A. Furtado, Luiz O. Faria

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Exposure to ionizing radiation has been found to induce changes in poly(vinylidene fluoride) (PVDF) homopolymers. The high dose gamma irradiation process induces the formation of C=C and C=O bonds in its [CH₂-CF₂]_n main chain. The irradiation also provokes crosslinking and chain scission. All these radio-induced defects lead to changes in the PVDF crystalline structure. As a consequence, it is common to observe a decrease in the melting temperature (T_M) and melting latent heat (L_M) and some changes in its ferroelectric features. We have investigated the possibility of preparing nanocomposites of PVDF with graphene oxide (GO) through the radio-induction of molecular bonds. In this work, we discuss how the gamma radiation interacts with the nanocomposite crystalline structure.

Keywords: gamma irradiation, graphene oxide, nanocomposites, PVDF

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Authors: Esther Baldwin

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It is well settled that the use of solitary confinement can cause psychological and physical harm to detainees. For juveniles, who are more susceptible to irreparable harm due to their underdeveloped psyches, the risks are exacerbated. Despite these risks, across the United States juvenile detainees are regularly held in isolation for prolonged periods of time. This essay will examine the broad impact of solitary confinement on juvenile detainees while giving particular focus to the story of Kalief Browder, a juvenile awaiting trial on Rikers Island in New York for a period of three years, nearly two years of which were spent in solitary confinement. Although sadly, his story is not uncommon, Kalief’s story offers a unique perspective in that it provides first-hand insight on the effects of solitary confinement on juveniles. It is our hope that by sharing his story, we will demand better detention practices and policies for juveniles under correctional control in the United States.

Keywords: criminal justice system, juveniles, Kalief browder, solitary confinement

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Authors: Matheus Fernando Pereira, Varese Salvador Timoteo

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In this work, we have solved the two-dimensional advection-diffusion equation numerically for a spatially dependent solute dispersion along non-uniform flow with a pulse type source in order to make a systematic study on the influence of medium heterogeneity, initial flow velocity, and initial dispersion coefficient parameters on the solutions of the equation. The behavior of the solutions is then investigated as we change the three parameters independently. Our results show that even though the parameters represent different physical features of the system, the effect on their variation is very similar. We also observe that the effects caused by the parameters on the concentration depend on the distance from the source. Finally, our numerical results are in good agreement with the exact solutions for all values of the parameters we used in our analysis.

Keywords: advection-diffusion equation, dispersion, numerical methods, pulse-type source

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Authors: M. J. Reis Lima, J. Oliveira, A. C. Sousa Pereira, M. C. Castilho, E. Teixeira-Lemos

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The increasing interest in plant sterol enriched foods is due to the fact that they reduce blood cholesterol concentrations without adverse side effects. In this context, enriched foods with phytosterols may be helpful in protecting population against atherosclerosis and cardiovascular diseases. The aim of the present work was to evaluate in a population of Viseu, Portugal, the consumption habits low-fat, plant sterol-enriched yoghurt. For this study, 577 inquiries were made and the sample was randomly selected for people shopping in various supermarkets. The preliminary results showed that the biggest consumers of these products were women aged 45 to 65 years old. Most of the people who claimed to buy these products consumed them once a day. Also, most of the consumers under antidyslipidemic therapeutics noticed positive effects on hypercholesterolemia.

Keywords: consumption habits, fermented milk, functional foods, low fat, phytosterols

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Authors: Esther T. Akinlabi, Stephen A. Akinlabi

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This paper reports on the effects of heat treatment on 3CR12 and AISI 316 stainless steel grades. Heat treatment was conducted on the steel grades and cooled using two different media; air and water in order to study the effect of each medium on the evolving properties of the samples. The heat treated samples were characterized through the evolving microstructure and hardness. It was found that there was a significant grain size reduction in both the heat treated stainless steel specimens compared to the parent materials. The finer grain sizes were achieved as a result of impediment to growth of one phase by the other. The Vickers micro-hardness values of the heat treated samples were higher compared to the parent materials due to the fact that each of the steel grades had a proportion of martensitic structures in their microstructures.

Keywords: austenite, ferrite, grain size, hardness, martensite, microstructure and stainless steel

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Authors: Americo Pereira, Ricardo Carvalho, Pedro Carvalho, Luis Corte-Real

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Generating 3D content is a task mostly done by hand. It requires specific knowledge not only on how to use the tools for the task but also on the fundamentals of a 3D environment. In this work, we show that automatic generation of content can be achieved, from a scene script, by leveraging existing tools so that non-experts can easily engage in a 3D content generation without requiring vast amounts of time in exploring and learning how to use specific tools. This proposal carries several benefits, including flexible scene synthesis with different levels of detail. Our preliminary results show that the automatically generated content is comparable to the content generated by users with low experience in 3D modeling while vastly reducing the amount of time required for the generation and adds support to implement flexible scenarios for visual scene visualization.

Keywords: 3D virtualization, multimedia, scene script, synthesis

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Authors: Jose Cristiano Pereira, Gilson Brito Alves Lima

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Ergonomics is a key factor affecting the operational safety and quality in the aircraft engine manufacturing industry and evidence shows that the lack of attention to it can increase the risk of accidents. In order to emphasize the importance of ergonomics, this paper systematically reviews the critical processes used in the aircraft engine production industry with focus on the ergonomic factors. about the subject to identify key ergonomic factors. Experts validated the factors and used AHP to rank the factors in order of significance. From the six key risk factors identified, the ones with the highest weight are psychological demand followed by understanding of operational side. These factors suggest that measures must be taken to improve ergonomic factors, quality and safety in the manufacturing of aircraft engines.

Keywords: ergonomics, safety, aviation, aircraft engine production

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Authors: Agarana Michael C., Akinlabi Esther T., Pule Kholopane

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In order to sustain the advantages of an advanced manufacturing technique, such as laser sintering, minimization of total processing cost of the parts being produced is very important. An efficient time management would usually very important in optimal cost attainment which would ultimately result in an efficient advanced manufacturing process planning and control. During Laser Scanning Process Scanning (SLS) procedures it is possible to adjust various manufacturing parameters which are used to influence the improvement of various mechanical and other properties of the products. In this study, Modelling and mathematical analysis, including sensitivity analysis, of the laser sintering process time were carried out. The results of the analyses were represented with graphs, from where conclusions were drawn. It was specifically observed that achievement of optimal total scanning time is key for economic efficiency which is required for sustainability of the process.

Keywords: modeling and analysis, optimal planning and control, laser sintering process, scanning time

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