Search results for: Víctor Molero Ayala
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 217

Search results for: Víctor Molero Ayala

67 Rural Community Knowledge, Attitude and Perceptions of Consuming Dried Vegetables in Central Region of Tanzania

Authors: Radegunda Kessy, Justus Ochieng, Victor Afari-Sefa, Takemore Chagomoka, Ngoni Nenguwo

Abstract:

Vegetables are excellent sources of dietary fiber, vitamins, and minerals which constitute an indispensable constituent of diets, but in Tanzania and other Sub-Saharan African countries, they are not readily available all year round due to seasonal variations in the production cycle. Drying of vegetables is one of the traditional methods for food preservation known to man. The Dodoma and Singida regions of Tanzania are characterized by semi-arid agro-climate, thereby experiencing short seasonal supply of fresh vegetables followed by long drought in which dried vegetables become an alternative to meet high household demands. A primary survey of 244 of rural consumers was carried out to understand how knowledge, attitudes, and perceptions of rural consumers affect consumption of dried vegetables. The sample respondents were all found to be aware of open sun drying of vegetables while less than 50% of them were aware of solar-dried vegetables. Consumers were highly concerned with the hygiene, nutritional values, taste, drying method, freshness, color of dried vegetables, timely availability and easiness of cooking as important factors they consider before they purchase dried vegetables. Logit model results show that gender, income, years of consuming dried vegetables, awareness of the importance of solar dried vegetables vis-à-vis sun-dried alternatives and employment status influenced rural consumer’s decision to purchase dried vegetables. Preference on dried vegetables differs across the regions which are also important considerations for any future planned interventions. The findings imply that development partners and policymakers need to design better social marketing and promotion techniques for the enhanced adoption of solar drying technology, which will greatly improve the quality and utilization of dried vegetables by target households.

Keywords: dried vegetables, postharvest management, sun drying, solar drying

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66 Secondary True to Life Polyethylene Terephthalate Nanoplastics: Obtention, Characterization, and Hazard Evaluation

Authors: Aliro Villacorta, Laura Rubio, Mohamed Alaraby, Montserrat López Mesas, Victor Fuentes-Cebrian, Oscar H. Moriones, Ricard Marcos, Alba Hernández.

Abstract:

Micro and nano plastics (MNPLs) are emergent environmental pollutants requiring urgent information on their potential risks to human health. One of the problems associated with the evaluation of their undesirable effects is the lack of real samples matching those resulting from the environmental degradation of plastic wastes. To such end, we propose an easy method to obtain polyethylene terephthalate nano plastics from water plastic bottles (PET-NPLs) but, in principle, applicable to any other plastic goods sources. An extensive characterization indicates that the proposed process produces uniform samples of PET-NPLs of around 100 nm, as determined by using a multi-angle and dynamic light scattering methodology. An important point to be highlighted is that to avoid the metal contamination resulting from methods using metal blades/burrs for milling, trituration, or sanding, we propose to use diamond burrs to produce metal-free samples. To visualize the toxicological profile of the produced PET-NPLs, we have evaluated their ability to be internalized by cells, their cytotoxicity, and their ability to induce oxidative stress and induce DNA damage. In this preliminary approach, we have detected their cellular uptake, but without the induction of significant biological effects. Thus, no relevant increases in toxicity, reactive oxygen species (ROS) induction, or DNA damage -as detected with the comet assay- have been observed. The use of real samples, as produced in this study, will generate relevant data in the discussion about the potential health risks associated with MNPLs exposures.

Keywords: nanoplastics, polyethylene terephthalate, physicochemical characterization, cell uptake, cytotoxicity

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65 Rock-Bed Thermocline Storage: A Numerical Analysis of Granular Bed Behavior and Interaction with Storage Tank

Authors: Nahia H. Sassine, Frédéric-Victor Donzé, Arnaud Bruch, Barthélemy Harthong

Abstract:

Thermal Energy Storage (TES) systems are central elements of various types of power plants operated using renewable energy sources. Packed bed TES can be considered as a cost–effective solution in concentrated solar power plants (CSP). Such a device is made up of a tank filled with a granular bed through which heat-transfer fluid circulates. However, in such devices, the tank might be subjected to catastrophic failure induced by a mechanical phenomenon known as thermal ratcheting. Thermal stresses are accumulated during cycles of loading and unloading until the failure happens. For instance, when rocks are used as storage material, the tank wall expands more than the solid medium during charge process, a gap is created between the rocks and tank walls and the filler material settles down to fill it. During discharge, the tank contracts against the bed, resulting in thermal stresses that may exceed the wall tank yield stress and generate plastic deformation. This phenomenon is repeated over the cycles and the tank will be slowly ratcheted outward until it fails. This paper aims at studying the evolution of tank wall stresses over granular bed thermal cycles, taking into account both thermal and mechanical loads, with a numerical model based on the discrete element method (DEM). Simulations were performed to study two different thermal configurations: (i) the tank is heated homogeneously along its height or (ii) with a vertical gradient of temperature. Then, the resulting loading stresses applied on the tank are compared as well the response of the internal granular material. Besides the study of the influence of different thermal configurations on the storage tank response, other parameters are varied, such as the internal angle of friction of the granular material, the dispersion of particles diameters as well as the tank’s dimensions. Then, their influences on the kinematics of the granular bed submitted to thermal cycles are highlighted.

Keywords: discrete element method (DEM), thermal cycles, thermal energy storage, thermocline

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64 Evaluation of Sustainable Business Model Innovation in Increasing the Penetration of Renewable Energy in the Ghana Power Sector

Authors: Victor Birikorang Danquah

Abstract:

Ghana's primary energy supply is heavily reliant on petroleum, biomass, and hydropower. Currently, Ghana gets its energy from hydropower (Akosombo and Bui), thermal power plants powered by crude oil, natural gas, and diesel, solar power, and imports from La Cote d'Ivoire. Until the early 2000s, large hydroelectric dams dominated Ghana's electricity generation. Due to unreliable weather patterns, Ghana increased its reliance on thermal power. However, thermal power contributes the highest percentage in terms of electricity generation in Ghana and is predominantly supplied by Independent Power Producers (IPPs). Ghana's electricity industry operates the corporate utility model as its business model. This model is typically' vertically integrated,' with a single corporation selling the majority of power generated by its generation assets to its retail business, which then sells the electricity to retail market consumers. The corporate utility model has a straightforward value proposition that is based on increasing the number of energy units sold. The unit volume business model drives the entire energy value chain to increase throughput, locking system users into unsustainable practices. This report uses the qualitative research approach to explore the electricity industry in Ghana. There is a need for increasing renewable energy, such as wind and solar, in electricity generation. The research recommends two critical business models for the penetration of renewable energy in Ghana's power sector. The first model is the peer-to-peer electricity trading model, which relies on a software platform to connect consumers and generators in order for them to trade energy directly with one another. The second model is about encouraging local energy generation, incentivizing optimal time-of-use behaviour, and allowing any financial gains to be shared among the community members.

Keywords: business model innovation, electricity generation, renewable energy, solar energy, sustainability, wind energy

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63 Disaster Victim Identification: A Social Science Perspective

Authors: Victor Toom

Abstract:

Albeit it is never possible to anticipate the full range of difficulties after a catastrophe, efforts to identify victims of mass casualty events have become institutionalized and standardized with the aim of effectively and efficiently addressing the many challenges and contingencies. Such ‘disaster victim identification’ (DVI) practices are dependent on the forensic sciences, are subject of national legislation, and are reliant on technical and organizational protocols to mitigate the many complexities in the wake of catastrophe. Apart from such technological, legal and bureaucratic elements constituting a DVI operation, victims’ families and their emotions are also part and parcel of any effort to identify casualties of mass human fatality incidents. Take for example the fact that forensic experts require (antemortem) information from the group of relatives to make identification possible. An identified body or body part is also repatriated to kin. Relatives are thus main stakeholders in DVI operations. Much has been achieved in years past regarding facilitating victims’ families’ issues and their emotions. Yet, how families are dealt with by experts and authorities is still considered a difficult topic. Due to sensitivities and required emphatic interaction with families on the one hand, and the rationalized DVI efforts, on the other hand, there is still scope for improving communication, providing information and meaningful inclusion of relatives in the DVI effort. This paper aims to bridge the standardized world of DVI efforts and families’ experienced realities and makes suggestions to further improve DVI efforts through inclusion of victims’ families. Based on qualitative interviews, the paper narrates involvement and experiences of inter alia DVI practitioners, victims’ families, advocates and clergy in the wake of the 1995 Srebrenica genocide which killed approximately 8,000 men, and the 9/11 in New York City with 2,750 victims. The paper shows that there are several models of including victims’ families into a DVI operation, and it argues for a model of where victims’ families become a partner in DVI operations.

Keywords: disaster victim identification (DVI), victims’ families, social science (qualitative), 9/11 attacks, Srebrenica genocide

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62 Influence of Online Media on Governance in Nigeria: The United States-Based Sahara Reporters as a Case Study

Authors: Sheriff Folarin, Oluwafunke Folarin, Hadassah Hussaini, Victor Jubril, Olaniyi Ayodele

Abstract:

Using a famous, unrestrained and fiery United States-based, Nigerian-owned Sahara Reporters as a case study, this paper examined the impact of online-based media on governance in Nigeria. The discourse is premised on the thesis that the internet has changed the face of journalism and that the mainstream but online-based media have made journalism more participatory than ever. Everyone who has something to say finds it easy to say it quickly and conveniently, unhinged or without being censored. This has made online journalism very popular and the number of online-based news platforms to be on the increase. As these platforms have given the citizens a means to interact and added to the content of the news, they have also succeeded in promoting partisanship. It thus becomes necessary to study the impact of the rabid news platform, Sahara Reporters, on governance in Africa’s biggest democracy, Nigeria. Few studies have examined the impact on governance of mainstream-online media platforms and those studies that did, have only focused on social media, such as Facebook and Twitter. This paper is a product of a bigger study, in which the research design entailed semi-structured interviews with participants from different sectors of the society and an analysis of contents from the Sahara Reporters website, from which data were collected. The findings revealed that through uncensored reporting and citizen participation on the platform of Sahara Reporters, there had been a significant people influence on governance in Nigeria, with government at two levels (national and state) sometimes shifting or yielding grounds, particularly from 2011-2016. The study also recognized the presence of counter-forces in the online community who want to discredit the information on the site. Through the lens of media dependency theory, the study concluded that the public now increasingly depends on online news media for information and the more news these media provide, the more the people depend on it, making it easy for them to influence governance.

Keywords: governance, media, online news, Sahara reporters

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61 Preparedness for Microbial Forensics Evidence Collection on Best Practice

Authors: Victor Ananth Paramananth, Rashid Muniginin, Mahaya Abd Rahman, Siti Afifah Ismail

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Safety issues, scene protection, and appropriate evidence collection must be handled in any bio crime scene. There will be a scene or multi-scene to be cordoned for investigation in any bio-incident or bio crime event. Evidence collection is critical in determining the type of microbial or toxin, its lethality, and its source. As a consequence, from the start of the investigation, a proper sampling method is required. The most significant challenges for the crime scene officer would be deciding where to obtain samples, the best sampling method, and the sample sizes needed. Since there could be evidence in liquid, viscous, or powder shape at a crime scene, crime scene officers have difficulty determining which tools to use for sampling. To maximize sample collection, the appropriate tools for sampling methods are necessary. This study aims to assist the crime scene officer in collecting liquid, viscous, and powder biological samples in sufficient quantity while preserving sample quality. Observational tests on sample collection using liquid, viscous, and powder samples for adequate quantity and sample quality were performed using UV light in this research. The density of the light emission varies upon the method of collection and sample types. The best tools for collecting sufficient amounts of liquid, viscous, and powdered samples can be identified by observing UV light. Instead of active microorganisms, the invisible powder is used to assess sufficient sample collection during a crime scene investigation using various collection tools. The liquid, powdered and viscous samples collected using different tools were analyzed using Fourier transform infrared - attenuate total reflection (FTIR-ATR). FTIR spectroscopy is commonly used for rapid discrimination, classification, and identification of intact microbial cells. The liquid, viscous and powdered samples collected using various tools have been successfully observed using UV light. Furthermore, FTIR-ATR analysis showed that collected samples are sufficient in quantity while preserving their quality.

Keywords: biological sample, crime scene, collection tool, UV light, forensic

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60 GBKMeans: A Genetic Based K-Means Applied to the Capacitated Planning of Reading Units

Authors: Anderson S. Fonseca, Italo F. S. Da Silva, Robert D. A. Santos, Mayara G. Da Silva, Pedro H. C. Vieira, Antonio M. S. Sobrinho, Victor H. B. Lemos, Petterson S. Diniz, Anselmo C. Paiva, Eliana M. G. Monteiro

Abstract:

In Brazil, the National Electric Energy Agency (ANEEL) establishes that electrical energy companies are responsible for measuring and billing their customers. Among these regulations, it’s defined that a company must bill your customers within 27-33 days. If a relocation or a change of period is required, the consumer must be notified in writing, in advance of a billing period. To make it easier to organize a workday’s measurements, these companies create a reading plan. These plans consist of grouping customers into reading groups, which are visited by an employee responsible for measuring consumption and billing. The creation process of a plan efficiently and optimally is a capacitated clustering problem with constraints related to homogeneity and compactness, that is, the employee’s working load and the geographical position of the consuming unit. This process is a work done manually by several experts who have experience in the geographic formation of the region, which takes a large number of days to complete the final planning, and because it’s human activity, there is no guarantee of finding the best optimization for planning. In this paper, the GBKMeans method presents a technique based on K-Means and genetic algorithms for creating a capacitated cluster that respects the constraints established in an efficient and balanced manner, that minimizes the cost of relocating consumer units and the time required for final planning creation. The results obtained by the presented method are compared with the current planning of a real city, showing an improvement of 54.71% in the standard deviation of working load and 11.97% in the compactness of the groups.

Keywords: capacitated clustering, k-means, genetic algorithm, districting problems

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59 Histological Characteristics of the Organs of Adult Zebrafish as a Biomarker for the Study of New Drugs with Effect on the Snake Venom of Bothrops alternatus

Authors: Jose Carlos Tavares Carvalho, Hady Keita, Giovanna Rocha Santana, Igor Victor Ferreira Dos Santos, Jesus Rafael Rodriguez Amado, Ariadna Lafourcade Prada, Adriana Maciel Ferreira, Helison Oliveira

Abstract:

Summary: As animal model, zebrafish can be a good opportunity to establish a profile of tissue alteration caused by Bothrops alternatus venom and to screen new anti-venom drugs. Objective: To establish tissue biomarkers from zebrafish injected by snake venom and elucidate the use of glucocorticoids in ophidic accidents. Materials and Methods: The Danio rerio fish were randomly divided into four groups: control group, venom group, Dexamethasone1h before venom injected group and Dexamethasone 1 h after venom injected group. The concentration of Bothrops alternatus venom was 0.13 mg/ml and the fish received 20µl/Fish. The Body weight measurement and histological characteristics of gills, kidneys, liver, and intestine were determinate. Results: Physical analysis shows necrosis accompanied by inflammation in animals receiving the Bothrops alternatus venom. Significant difference was observed in the variation of weight between the control group, and the groups received the venom (t student test, p < 0.05). The average histological alterations index of gill, liver, kidney or intestine was statistically higher in animals received the venom (t Student test, p < 0.05). The alterations were lower in the groups that received Dexamethasone 1h before and after venom injected compared to the group that received only the venom. Dexamethasone 1h before venom injected group had minor histopathological alterations. Conclusion: The organs of zebrafish may be a tissue biomarker of alterations from Bothrops alternatus venom and dexamethasone reduced the damage caused by this venom in the organs studied, which may suggest the use of zebrafish as animal model for research related to screening new drug against snake venom.

Keywords: zebrafish, snake venom, biomarker, drugs

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58 Electroencephalography Correlates of Memorability While Viewing Advertising Content

Authors: Victor N. Anisimov, Igor E. Serov, Ksenia M. Kolkova, Natalia V. Galkina

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The problem of memorability of the advertising content is closely connected with the key issues of neuromarketing. The memorability of the advertising content contributes to the marketing effectiveness of the promoted product. Significant directions of studying the phenomenon of memorability are the memorability of the brand (detected through the memorability of the logo) and the memorability of the product offer (detected through the memorization of dynamic audiovisual advertising content - commercial). The aim of this work is to reveal the predictors of memorization of static and dynamic audiovisual stimuli (logos and commercials). An important direction of the research was revealing differences in psychophysiological correlates of memorability between static and dynamic audiovisual stimuli. We assumed that static and dynamic images are perceived in different ways and may have a difference in the memorization process. Objective methods of recording psychophysiological parameters while watching static and dynamic audiovisual materials are well suited to achieve the aim. The electroencephalography (EEG) method was performed with the aim of identifying correlates of the memorability of various stimuli in the electrical activity of the cerebral cortex. All stimuli (in the groups of statics and dynamics separately) were divided into 2 groups – remembered and not remembered based on the results of the questioning method. The questionnaires were filled out by survey participants after viewing the stimuli not immediately, but after a time interval (for detecting stimuli recorded through long-term memorization). Using statistical method, we developed the classifier (statistical model) that predicts which group (remembered or not remembered) stimuli gets, based on psychophysiological perception. The result of the statistical model was compared with the results of the questionnaire. Conclusions: Predictors of the memorability of static and dynamic stimuli have been identified, which allows prediction of which stimuli will have a higher probability of remembering. Further developments of this study will be the creation of stimulus memory model with the possibility of recognizing the stimulus as previously seen or new. Thus, in the process of remembering the stimulus, it is planned to take into account the stimulus recognition factor, which is one of the most important tasks for neuromarketing.

Keywords: memory, commercials, neuromarketing, EEG, branding

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57 Comparative Effects of Dietary Ocimum Gratissimum and Antibiotic Growth Promoter on Body Weight and Gut Morphometry of Broiler Starters

Authors: Victor U. Odoemelam, Ihemdirim C. Unamba-Opara, Martins C. Anyanwuocha

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Antibiotics used as growth promoters in animal feeds have been criticized and banned in many nations due to possible development of both drug resistance, cross resistance and multiple resistances by consumers. Numerous additives are now being used or proposed as alternatives. A study to compare the effects of Ocimum gratissimum (Scent leaf) and antibiotic growth promoter (Oxytetracycline HCl) on growth performance and intestinal morphology of starter broiler birds was conducted using ninety six (96) days old broiler birds. The birds were randomly assigned to four treatments with each treatment comprising 24 birds replicated three times with 8 birds per replicate in a completely randomized design experiment. Four diets (T1 control diet without Oxytetracycline HCl and Ocimum gratissimum; T2 had Oxytetracycline HCl; T3 had 1% Ocimum gratissimum; T4 had 1.5% Ocimum gratissimum) were formulated and offered ad libitum to the respective birds. Data was collected on feed intake, body weight gain and feed conversion ratio (FCR) also Jejenal sections of the intestine were collected for examination of Villi length and Crypt depth at the end of starter phase. Results show that there were no significant difference (P>0.05) observed in feed intake and final body weight. However, feed conversion ratio (FCR) and daily weight gain significantly differed (P<0.05). T1, T2, and T4 were similar, however T2 differed (P<0.05) from T3. FCR followed the same pattern. Dietary treatment significantly (P<0.05) affected Villi length, Crypt depth and Villi length/crypt depth ratio. Birds fed OG containing diets, had significantly higher (P<0.05) villi length/crypt depth ratio. However, this did not translate to a significantly higher body weight gain or feed conversion ratio. It can be concluded that O. gratissimum can replace antibiotic growth promoter (Oxytetracycline HCl) since their effect on performance were similar.

Keywords: antibiotics, body weight, feed additives, intestinal morphology, phytogenics

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56 Robustness of the Deep Chroma Extractor and Locally-Normalized Quarter Tone Filters in Automatic Chord Estimation under Reverberant Conditions

Authors: Luis Alvarado, Victor Poblete, Isaac Gonzalez, Yetzabeth Gonzalez

Abstract:

In MIREX 2016 (http://www.music-ir.org/mirex), the deep neural network (DNN)-Deep Chroma Extractor, proposed by Korzeniowski and Wiedmer, reached the highest score in an audio chord recognition task. In the present paper, this tool is assessed under acoustic reverberant environments and distinct source-microphone distances. The evaluation dataset comprises The Beatles and Queen datasets. These datasets are sequentially re-recorded with a single microphone in a real reverberant chamber at four reverberation times (0 -anechoic-, 1, 2, and 3 s, approximately), as well as four source-microphone distances (32, 64, 128, and 256 cm). It is expected that the performance of the trained DNN will dramatically decrease under these acoustic conditions with signals degraded by room reverberation and distance to the source. Recently, the effect of the bio-inspired Locally-Normalized Cepstral Coefficients (LNCC), has been assessed in a text independent speaker verification task using speech signals degraded by additive noise at different signal-to-noise ratios with variations of recording distance, and it has also been assessed under reverberant conditions with variations of recording distance. LNCC showed a performance so high as the state-of-the-art Mel Frequency Cepstral Coefficient filters. Based on these results, this paper proposes a variation of locally-normalized triangular filters called Locally-Normalized Quarter Tone (LNQT) filters. By using the LNQT spectrogram, robustness improvements of the trained Deep Chroma Extractor are expected, compared with classical triangular filters, and thus compensating the music signal degradation improving the accuracy of the chord recognition system.

Keywords: chord recognition, deep neural networks, feature extraction, music information retrieval

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55 Deep Cryogenic Treatment With Subsequent Aging Applied to Martensitic Stainless Steel: Evaluation of Hardness, Tenacity and Microstructure

Authors: Victor Manuel Alcántara Alza

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The way in which the application of the deep cryogenic treatment DCT(-196°C) affects, applied with subsequent aging, was investigated, regarding the mechanical properties of hardness, toughness and microstructure, applied to martensitic stainless steels, with the aim of establishing a different methodology compared to the traditional DCT cryogenic treatment with subsequent tempering. For this experimental study, a muffle furnace was used, first subjecting the specimens to deep cryogenization in a liquid Nitrogen bath/4h, after being previously austenitized at the following temperatures: 1020-1030-1040-1050 (°C) / 1 hour; and then tempered in oil. A first group of cryogenic samples were subjected to subsequent aging at 150°C, with immersion times: 2.5 -5- 10 - 20 - 50 – 100 (h). The next group was subjected to subsequent tempering at temperatures: 480-500-510-520-530-540 (°C)/ 2h. The hardness tests were carried out under standards, using a Universal Durometer, and the readings were made on the HRC scale. The Impact Resistance tests were carried out in a Charpy machine following the ASTM E 23 – 93ª standard. Measurements were taken in joules. Microscopy was performed at the optical level using a 1000X microscope. It was found: For the entire aging interval, the samples austenitized at 1050°C present greater hardness than austenitized at 1040°C, with the maximum peak aged being at 30h. In all cases, the aged samples exceed the hardness of the tempered samples, even in their minimum values. In post-tempered samples, the tempering temperature hardly have effect on the impact strength of material. In the Cryogenic Treatment: DCT + subsequent aging, the maximum hardness value (58.7 HRC) is linked to an impact toughness value (54J) obtained with aging time of 39h, which is considered an optimal condition. The higher hardness of steel after the DCT treatment is attributed to the transformation of retained austenite into martensite. The microstructure is composed mainly of lath martensite; and the original grain size of the austenite can be appreciated. The choice of the combination: Hardness-toughness, is subject to the required service conditions of steel.

Keywords: deep cryogenic treatment; aged precipitation; martensitic steels;, mechanical properties; martensitic steels, hardness, carbides precipitaion

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54 Investigation of the Technological Demonstrator 14x B in Different Angle of Attack in Hypersonic Velocity

Authors: Victor Alves Barros Galvão, Israel Da Silveira Rego, Antonio Carlos Oliveira, Paulo Gilberto De Paula Toro

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The Brazilian hypersonic aerospace vehicle 14-X B, VHA 14-X B, is a vehicle integrated with the hypersonic airbreathing propulsion system based on supersonic combustion (scramjet), developing in Aerothermodynamics and hypersonic Prof. Henry T. Nagamatsu Laboratory, to conduct demonstration in atmospheric flight at the speed corresponding to Mach number 7 at an altitude of 30km. In the experimental procedure the hypersonic shock tunnel T3 was used, installed in that laboratory. This device simulates the flow over a model is fixed in the test section and can also simulate different atmospheric conditions. The scramjet technology offers substantial advantages to improve aerospace vehicle performance which flies at a hypersonic speed through the Earth's atmosphere by reducing fuel consumption on board. Basically, the scramjet is an aspirated aircraft engine fully integrated that uses oblique/conic shock waves generated during hypersonic flight, to promote the deceleration and compression of atmospheric air in scramjet inlet. During the hypersonic flight, the vehicle VHA 14-X will suffer atmospheric influences, promoting changes in the vehicle's angles of attack (angle that the mean line of vehicle makes with respect to the direction of the flow). Based on this information, a study is conducted to analyze the influences of changes in the vehicle's angle of attack during the atmospheric flight. Analytical theoretical analysis, simulation computational fluid dynamics and experimental investigation are the methodologies used to design a technological demonstrator prior to the flight in the atmosphere. This paper considers analysis of the thermodynamic properties (pressure, temperature, density, sound velocity) in lower surface of the VHA 14-X B. Also, it considers air as an ideal gas and chemical equilibrium, with and without boundary layer, considering changes in the vehicle's angle of attack (positive and negative in relation to the flow) and bi-dimensional expansion wave theory at the expansion section (Theory of Prandtl-Meyer).

Keywords: angle of attack, experimental hypersonic, hypersonic airbreathing propulsion, Scramjet

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53 Assessment of the Performance of the Sonoreactors Operated at Different Ultrasound Frequencies, to Remove Pollutants from Aqueous Media

Authors: Gabriela Rivadeneyra-Romero, Claudia del C. Gutierrez Torres, Sergio A. Martinez-Delgadillo, Victor X. Mendoza-Escamilla, Alejandro Alonzo-Garcia

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Ultrasonic degradation is currently being used in sonochemical reactors to degrade pollutant compounds from aqueous media, as emerging contaminants (e.g. pharmaceuticals, drugs and personal care products.) because they can produce possible ecological impacts on the environment. For this reason, it is important to develop appropriate water and wastewater treatments able to reduce pollution and increase reuse. Pollutants such as textile dyes, aromatic and phenolic compounds, cholorobenzene, bisphenol-A and carboxylic acid and other organic pollutants, can be removed from wastewaters by sonochemical oxidation. The effect on the removal of pollutants depends on the type of the ultrasonic frequency used; however, not much studies have been done related to the behavior of the fluid into the sonoreactors operated at different ultrasonic frequencies. Based on the above, it is necessary to study the hydrodynamic behavior of the liquid generated by the ultrasonic irradiation to design efficient sonoreactors to reduce treatment times and costs. In this work, it was studied the hydrodynamic behavior of the fluid in sonochemical reactors at different frequencies (250 kHz, 500 kHz and 1000 kHz). The performances of the sonoreactors at those frequencies were simulated using computational fluid dynamics (CFD). Due to there is great sound speed gradient between piezoelectric and fluid, k-e models were used. Piezoelectric was defined as a vibration surface, to evaluate the different frequencies effect on the fluid into sonochemical reactor. Structured hexahedral cells were used to mesh the computational liquid domain, and fine triangular cells were used to mesh the piezoelectric transducers. Unsteady state conditions were used in the solver. Estimation of the dissipation rate, flow field velocities, Reynolds stress and turbulent quantities were evaluated by CFD and 2D-PIV measurements. Test results show that there is no necessary correlation between an increase of the ultrasonic frequency and the pollutant degradation, moreover, the reactor geometry and power density are important factors that should be considered in the sonochemical reactor design.

Keywords: CFD, reactor, ultrasound, wastewater

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52 Modification of Polyolefin Membrane Using Supercritical Carbon Dioxide for Redox Flow Batteries

Authors: Vadim V. Zefirov, Victor E. Sizov, Marina A. Pigaleva, Igor V. Elmanovich, Mikhail S. Kondratenko, Marat O. Gallyamov

Abstract:

This work presents a novel method for treating porous hydrophobic polyolefin membranes using supercritical carbon dioxide that allows usage of the modified membrane in redox flow batteries with an aqueous electrolyte. Polyolefin membranes are well known and widely used, however, they cannot be used as separators in redox flow batteries with an aqueous electrolyte since they have insufficient wettability, and therefore do not provide sufficient proton conductivity. The main aim of the presented work was the development of hydrophilic composites based on cheap membranes and precursors. Supercritical fluid was used as a medium for the deposition of the hydrophilic phase on the hydrophobic surface of the membrane. Due to the absence of negative capillary effects in a supercritical medium, a homogeneous composite is obtained as a result of synthesis. The in-situ synthesized silicon oxide nanoparticles and the chitosan polymer layer act as the hydrophilic phase and not only increase the affinity of the membrane towards the electrolyte, but also reduce the pore size of the polymer matrix, which positively affects the ion selectivity of the membrane. The composite material obtained as a result of synthesis has enhanced hydrophilic properties and is capable of providing proton conductivity in redox flow batteries. The morphology of the obtained composites was characterized by electron microscopy. To analyze the phase composition, infrared spectroscopy was used. The hydrophilic properties were studied by water contact angle measurements. In addition, the proton conductivity and ion selectivity of the obtained samples were studied, and tests in real redox flow batteries were performed. As a result, modified membrane was characterised in detail and moreover it was shown that modified cheap polyolefin membranes have pronounced proton conductivity and high ion selectivity, so their performance in a real redox flow battery approaches expensive commercial analogues, reaching 70% of energy efficiency.

Keywords: carbon dioxide, chitosan, polymer membrane, redox flow batteries, silica nanoparticles, supercritical fluid

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51 The Role of Climate-Smart Agriculture in the Contribution of Small-Scale Farming towards Ensuring Food Security in South Africa

Authors: Victor O. Abegunde, Melusi Sibanda

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There is need for a great deal of attention on small-scale agriculture for livelihood and food security because of the expanding global population. Small-scale agriculture has been identified as a major driving force of agricultural and rural development. However, the high dependence of the sector on natural and climatic resources has made small-scale farmers highly vulnerable to the adverse impact of climatic change thereby necessitating the need for embracing practices or concepts that will help absorb shocks from changes in climatic condition. This study examines the strategic position of small-scale farming in South African agriculture and in ensuring food security in the country, the vulnerability of small-scale agriculture to climate change and the potential of the concept of climate-smart agriculture to tackle the challenge of climate change. The study carried out a systematic review of peer-reviewed literature touching small-scale agriculture, climate change, food security and climate-smart agriculture, employing the realist review method. Findings revealed that increased productivity in the small-scale agricultural sector has a great potential of improving the food security of households in South Africa and reducing dependence on food purchase in a context of high food price inflation. Findings, however, also revealed that climate change affects small-scale subsistence farmers in terms of productivity, food security and family income, categorizing the impact on smallholder livelihoods into three major groups; biological processes, environmental and physical processes and impact on health. Analysis of the literature consistently showed that climate-smart agriculture integrates the benefits of adaptation and resilience to climate change, mitigation, and food security. As a result, farming households adopting climate-smart agriculture will be better off than their counterparts who do not. This study concludes that climate-smart agriculture could be a very good bridge linking small-scale agricultural sector and agricultural productivity and development which could bring about the much needed food security.

Keywords: climate change, climate-smart agriculture, food security, small-scale

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50 Digital Transformation: Actionable Insights to Optimize the Building Performance

Authors: Jovian Cheung, Thomas Kwok, Victor Wong

Abstract:

Buildings are entwined with smart city developments. Building performance relies heavily on electrical and mechanical (E&M) systems and services accounting for about 40 percent of global energy use. By cohering the advancement of technology as well as energy and operation-efficient initiatives into the buildings, people are enabled to raise building performance and enhance the sustainability of the built environment in their daily lives. Digital transformation in the buildings is the profound development of the city to leverage the changes and opportunities of digital technologies To optimize the building performance, intelligent power quality and energy management system is developed for transforming data into actions. The system is formed by interfacing and integrating legacy metering and internet of things technologies in the building and applying big data techniques. It provides operation and energy profile and actionable insights of a building, which enables to optimize the building performance through raising people awareness on E&M services and energy consumption, predicting the operation of E&M systems, benchmarking the building performance, and prioritizing assets and energy management opportunities. The intelligent power quality and energy management system comprises four elements, namely the Integrated Building Performance Map, Building Performance Dashboard, Power Quality Analysis, and Energy Performance Analysis. It provides predictive operation sequence of E&M systems response to the built environment and building activities. The system collects the live operating conditions of E&M systems over time to identify abnormal system performance, predict failure trends and alert users before anticipating system failure. The actionable insights collected can also be used for system design enhancement in future. This paper will illustrate how intelligent power quality and energy management system provides operation and energy profile to optimize the building performance and actionable insights to revitalize an existing building into a smart building. The system is driving building performance optimization and supporting in developing Hong Kong into a suitable smart city to be admired.

Keywords: intelligent buildings, internet of things technologies, big data analytics, predictive operation and maintenance, building performance

Procedia PDF Downloads 157
49 Framework for Explicit Social Justice Nursing Education and Practice: A Constructivist Grounded Theory Research

Authors: Victor Abu

Abstract:

Background: Social justice ideals are considered as the foundation of nursing practice. These ideals are not always clearly integrated into nursing professional standards or curricula. This hinders concerted global nursing agendas for becoming aware of social injustice or engaging in action for social justice to improve the health of individuals and groups. Aim and objectives: The aim was to create an educational framework for empowering nursing students for social justice awareness and action. This purpose was attained by understanding the meaning of social justice, the effect of social injustice, the visibility of social justice learning, and ways of integrating social justice in nursing education and practice. Methods: Critical interpretive methodologies and constructivist grounded theory research designs guided the processes of recruiting nursing students (n = 11) and nurse educators (n = 11) at a London nursing university to participate in interviews and focus groups, which were analysed by coding systems. Findings: Firstly, social justice was described as ethical practices that enable individuals and groups to have good access to health resources. Secondly, social injustice was understood as unfair practices that caused minimal access to resources, social deprivation, and poor health. Thirdly, social justice learning was considered to be invisible in nursing education due to a lack of explicit modules, educator knowledge, and organisational support. Lastly, explicit modules, educating educators, and attracting leaders’ support were suggested as approaches for the visible integration of social justice in nursing education and practice. Discussion: This research proposes approaches for nursing awareness and action for the development of critical active nurse-learner, critical conscious nurse-educator, and servant nurse leader. The framework on Awareness for Social Justice Action (ASJA) created in this research is an approach for empowering nursing students for social justice practices. Conclusion: This research contributes to and advocates for greater nursing scholarship to raise the spotlight on social justice in the profession.

Keywords: social justice, nursing practice, nursing education, nursing curriculum, social justice awareness, social justice action, constructivist grounded theory

Procedia PDF Downloads 58
48 Robotic Exoskeleton Response During Infant Physiological Knee Kinematics

Authors: Breanna Macumber, Victor A. Huayamave, Emir A. Vela, Wangdo Kim, Tamara T. Chamber, Esteban Centeno

Abstract:

Spina bifida is a type of neural tube defect that affects the nervous system and can lead to problems such as total leg paralysis. Treatment requires physical therapy and rehabilitation. Robotic exoskeletons have been used for rehabilitation to train muscle movement and assist in injury recovery; however, current models focus on the adult populations and not on the infant population. The proposed framework aims to couple a musculoskeletal infant model with a robotic exoskeleton using vacuum-powered artificial muscles to provide rehabilitation to infants affected by spina bifida. The study that drove the input values for the robotic exoskeleton used motion capture technology to collect data from the spontaneous kicking movement of a 2.4-month-old infant lying supine. OpenSim was used to develop the musculoskeletal model, and Inverse kinematics was used to estimate hip joint angles. A total of 4 kicks (A, B, C, D) were selected, and the selection was based on range, transient response, and stable response. Kicks had at least 5° of range of motion with a smooth transient response and a stable period. The robotic exoskeleton used a Vacuum-Powered Artificial Muscle (VPAM) the structure comprised of cells that were clipped in a collapsed state and unclipped when desired to simulate infant’s age. The artificial muscle works with vacuum pressure. When air is removed, the muscle contracts and when air is added, the muscle relaxes. Bench testing was performed using a 6-month-old infant mannequin. The previously developed exoskeleton worked really well with controlled ranges of motion and frequencies, which are typical of rehabilitation protocols for infants suffering with spina bifida. However, the random kicking motion in this study contained high frequency kicks and was not able to accurately replicate all the investigated kicks. Kick 'A' had a greater error when compared to the other kicks. This study has the potential to advance the infant rehabilitation field.

Keywords: musculoskeletal modeling, soft robotics, rehabilitation, pediatrics

Procedia PDF Downloads 118
47 Applying the Eye Tracking Technique for the Evaluation of Oculomotor System in Patients Survived after Cerebellar Tumors

Authors: Marina Shurupova, Victor Anisimov, Alexander Latanov

Abstract:

Background: The cerebellar lesions inevitably provoke oculomotor impairments in patients of different age. Symptoms of subtentorial tumors, particularly medulloblastomas, include static and dynamic coordination disorders (ataxia, asynergia, imbalance), hypo-muscle tonus, disruption of the cranial nerves, and within the oculomotor system - nystagmus (fine or gross). Subtentorial tumors can also affect the areas of cerebellum that control the oculomotor system. The noninvasive eye-tracking technology allows obtaining multiple oculomotor characteristics such as the number of fixations and their duration, amplitude, latency and velocity of saccades, trajectory and scan path of gaze during the process of the visual field navigation. Eye tracking could be very useful in clinical studies serving as convenient and effective tool for diagnostics. The aim: We studied the dynamics of oculomotor system functioning in patients undergoing remission from cerebellar tumors removal surgeries and following neurocognitive rehabilitation. Methods: 38 children (23 boys, 15 girls, 9-17 years old) that have recovered from the cerebellar tumor-removal surgeries, radiation therapy and chemotherapy and were undergoing course of neurocognitive rehabilitation participated in the study. Two tests were carried out to evaluate oculomotor performance - gaze stability test and counting test. The monocular eye movements were recorded with eye tracker ArringtonResearch (60 Hz). Two experimental sessions with both tests were conducted before and after rehabilitation courses. Results: Within the final session of both tests we observed remarkable improvement in oculomotor performance: 1) in the gaze stability test the spread of gaze positions significantly declined compared to the first session, and 2) the visual path in counting test significantly shortened both compared to the first session. Thus, neurocognitive rehabilitation improved the functioning of the oculomotor system in patients following the cerebellar tumor removal surgeries and subsequent therapy. Conclusions: The experimental data support the effectiveness of the utilization of the eye tracking technique as diagnostic tool in the field of neurooncology.

Keywords: eye tracking, rehabilitation, cerebellar tumors, oculomotor system

Procedia PDF Downloads 161
46 Exoskeleton Response During Infant Physiological Knee Kinematics And Dynamics

Authors: Breanna Macumber, Victor A. Huayamave, Emir A. Vela, Wangdo Kim, Tamara T. Chamber, Esteban Centeno

Abstract:

Spina bifida is a type of neural tube defect that affects the nervous system and can lead to problems such as total leg paralysis. Treatment requires physical therapy and rehabilitation. Robotic exoskeletons have been used for rehabilitation to train muscle movement and assist in injury recovery; however, current models focus on the adult populations and not on the infant population. The proposed framework aims to couple a musculoskeletal infant model with a robotic exoskeleton using vacuum-powered artificial muscles to provide rehabilitation to infants affected by spina bifida. The study that drove the input values for the robotic exoskeleton used motion capture technology to collect data from the spontaneous kicking movement of a 2.4-month-old infant lying supine. OpenSim was used to develop the musculoskeletal model, and Inverse kinematics was used to estimate hip joint angles. A total of 4 kicks (A, B, C, D) were selected, and the selection was based on range, transient response, and stable response. Kicks had at least 5° of range of motion with a smooth transient response and a stable period. The robotic exoskeleton used a Vacuum-Powered Artificial Muscle (VPAM) the structure comprised of cells that were clipped in a collapsed state and unclipped when desired to simulate infant’s age. The artificial muscle works with vacuum pressure. When air is removed, the muscle contracts and when air is added, the muscle relaxes. Bench testing was performed using a 6-month-old infant mannequin. The previously developed exoskeleton worked really well with controlled ranges of motion and frequencies, which are typical of rehabilitation protocols for infants suffering with spina bifida. However, the random kicking motion in this study contained high frequency kicks and was not able to accurately replicate all the investigated kicks. Kick 'A' had a greater error when compared to the other kicks. This study has the potential to advance the infant rehabilitation field.

Keywords: musculoskeletal modeling, soft robotics, rehabilitation, pediatrics

Procedia PDF Downloads 83
45 Promoter Methylation of RASSF1A and MGMT Genes in Head and Neck Squamous Cell Carcinoma

Authors: Vitor Rafael Regiani, Carlos Henrique Viesi Do Nascimento Filho, Patricia Matos Biselli-Chicote, Claudia Aparecida Rainho, Luiz Sergio Raposo, José Victor Maniglia, Eny Maria Goloni-Bertollo, Erika Cristina Pavarino

Abstract:

Promoter hypermethylation of tumor-related genes has been associated with prognosis in early-stage head-and-neck cancers, providing strong evidence that these hypermethylated genes are valuable biomarkers for prognostic evaluation. Hence, we selected the MGMT and RASSF1A genes to examine the methylation status in head and neck squamous cell carcinomas (HNSCC) samples matched with non-tumor tissues (tumor-surrounding tissues or peripheral blood samples). DNA methylation analysis was based on Methylation-Sensitive High Resolution Melting, and the methylation status was correlated with clinic-pathological characteristics of the patients. RASSF1A and MGMT promoter methylation was detected in 43.24% (16/37) and in 44.44% (16/36) of the tumors, respectively. RASSF1A and MGMT methylation was significantly more frequent in tumor tissue than non-tumor tissues, as well as, simultaneous methylation of RASSF1A and MGMT also was higher in tumor tissue than non-tumor tissues. In relation to anatomic site, larynx cancer presented significant methylation of MGMT gene compared to tumor-surrounding tissue. The frequency of RASSF1A and MGMT promoter methylated was higher in tumor tissues in relation to peripheral blood from the same patient. No association was found between methylation and the variables analyzed, including gender, age, smoking or alcohol drinking habits. Clinic-pathological characteristics also showed no association in the presence of methylation. The Kaplan–Meier's method showed no association of methylation and both disease-free and overall survival. In conclusion, the presence of epigenetic abnormalities in normal-appearing tissue corroborates the hypothesis of the ‘field cancerization', or it can reflect preneoplastic and/or preinvasive. Moreover, MGMT methylation may serve as an important laryngeal cancer biomarker because it showed significant difference between laryngeal cancer and surrounding tumor tissues.

Keywords: head and neck cancer, DNA methylation, MGMT promoter methylation, RASSF1A promoter methylation

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44 Remediation of Oil and Gas Exploration and Production (O&G E&P) Wastes Using Soil-Poultry Dropping Amendment

Authors: Ofonime U. M. John, Justina I. R. Udotong, Victor O. Nwaugo, Ime R. Udotong

Abstract:

Oily wastes from oil and gas exploration and production (O&G E&P) activities were remediated for twelve weeks using Soil-Poultry dropping amendment. Culture-dependent microbiological, chemical and enzymatic techniques were employed to assess the efficacy of remediation process. Microbiological activities of the remediated wastes showed increased hydrocarbonoclastic microbial populations with increased remediation time; 2.7±0.1 x 105cfu/g to 8.3 ± 0.04 x106cfu/g for hydrocarbon utilizing bacteria, 1.7 ± 0.2 x103cfu/g to 6.0 ± 0.01 x 104cfu/g for hydrocarbon utilizing fungi and 2.2 ± 0.1 x 102cfu/g to 6.7 ± 0.1 x 103cfu/g for hydrocarbon utilizing actinomycetes. Bacteria associated with the remediated wastes after the remediation period included the genera Bacillus, Psuedomonas, Beijerinckia, Acinetobacter, Alcaligenes and Serratia. Fungal isolates included species of Penicillium, Aspergillus and Cladosporium, while the Actinomycetes included species of Rhodococcus, Nocardia and Streptomyces. Slight fluctuations in pH values between 6.5± 0.2 and 7.1 ± 0.08 were recorded throughout the process, while total petroleum hydrocarbon (TPH) content decreased from 89, 900 ± 0.03mg/kg to 425 ± 0.1 mg/kg after twelve weeks of remediation. The polycyclic aromatic hydrocarbon (PAH) levels decreased with increased remediation time; naphthalene, flourene, pheneanthrene, anthracene, pyrene, chrysene and benzo(b)flouranthene showed decreased values < 0.01 after twelve weeks of remediation. Enzyme activities revealed increased dehydrogenase and urease activities with increased remediation time and decreased phenol oxidase activity with increased remediation period. There was a positive linear correlation between densities of hydrocarbonoclastic microbes and dehydrogenase activity. On the contrary, phenol oxidase and urease activities showed negative correlation with microbial population. Results of this study confirmed that remediation of oily wastes using soil-poultry dropping amendment can result in eco-friendly O&G E&P wastes. It also indicates that urease and phenol oxidase activities can be reliable indices/tools to monitor PAH levels and rates of petroleum hydrocarbon degradation.

Keywords: dehydrogenase activity, oily wastes, remediation, soil-poultry dropping amendment

Procedia PDF Downloads 322
43 The Effectiveness of E-Training on the Attitude and Skill Competencies of Vocational High School Teachers during Covid-19 Pandemic in Indonesia

Authors: Sabli, Eddy Rismunandar, Akhirudin, Nana Halim, Zulfikar, Nining Dwirosanti, Wila Ningsih, Pipih Siti Sofiah, Danik Dania Asadayanti, Dewi Eka Arini Algozi, Gita Mahardika Pamuji, Ajun, Mangasa Aritonang, Nanang Rukmana, Arief Rachman Wonodhipo, Victor Imanuel Nahumury, Lili Husada, Wawan Saepul Irwan, Al Mukhlas Fikri

Abstract:

Covid-19 pandemic has widely impacted the lives. An adaptive strategy must be quickly formulated to maintain the quality of education, especially by vocational school which technical skill competencies are highly needed. This study aimed to evaluate the effectiveness of e-training on the attitude and skill competencies of vocational high school teachers in Indonesia. A total of 720 Indonesian vocational high school teachers with various programs, including hospitality, administration, online business and marketing, culinary arts, fashion, cashier, tourism, haircut, and accounting participated e-training for a month. The training used electronic learning management system to provide materials (modules, presentation slides, and tutorial videos), tasks, and evaluations. Tutorial class was carried out by video conference meeting. Attitude and skill competencies were evaluated before and after the training. Meanwhile, the teachers also gave satisfactory feedback on the quality of the organizer and tutors. Data analysis used paired sample t-test and Anova with Tukey’s post hoc test. The results showed that e-training significantly increased the score of attitude and skill competencies of the teachers (p <0,05). Moreover, the remarkable increase was found among hospitality (57,5%), cashier (50,1%), and online business and marketing (48,7%) teachers. However, the effect among fashion, tourism and haircut teachers was less obvious. In addition, the satisfactory score on the quality of the organizer and tutors were 88,9 (very good), and 93,5 (excellence), respectively. The study concludes that a well-organized e-training could increase the attitude and skill competencies of Indonesian vocational high school teachers during Covid-19 pandemic.

Keywords: E-training, skill, teacher, vocational high school

Procedia PDF Downloads 148
42 Selective Fermentations of Monosaccharides by Osmotolerant Yeast Cultures

Authors: Elizabeth Loza-Valerdi, Victor Pardiñas-Rios, Arnulfo Pluma-Pluma, Andres Breton-Toral, Julio Cercado-Jaramillo

Abstract:

The purification processes for mixtures of isomeric monosaccharides using industrial chromatographic methods poses a serious technical challenge. Mixtures of 2 or 3 monosaccharides are difficult to separate by strictly physical or chemical techniques. Differential fermentation by microbial cultures is an increasingly interesting way of selective enrichment in a particular kind of monosaccharides when a mixture of them is present in the solution, and only one has economical value. Osmotolerant yeast cultures provide an interesting source of biocatalysts for the selective catabolism of monosaccharides in media containing high concentrations of total soluble sugars. A collection of 398 yeast strains has been obtained using endemic and unique sources of fruit juices, industrial syrups, honey, and other high sugar content substrates, either natural or man made, products and by-products from Mexico. The osmotolerance of the strains was assessed by plate assay both in glucose (20-40-60%w/w). Strains were classified according to their osmotolerance in low, medium or highly tolerant to high glucose concentrations. The purified cultures were tested by their ability to growth in a solid plate media or liquid media of Yeas Nitrogen Base (YNB), added with specific monosaccharides as sole carbon source (glucose, galactose, lactose and fructose). Selected strains were subsequently tested in fermentation experiments with mixtures of two monosaccharides (galactose/glucose and glucose/fructose). Their ability to grow and selectively catabolize one monosaccharide was evaluated. Growth, fermentation activity and products of metabolism were determined by plate counts, CO2 production, turbidity and chromatographic analysis by HPLC. Selective catabolism of one monosaccharide in liquid media containing two monosaccharides was confirmed for 8 strains. Ion Exchange chromatographic processes were used in production of high fructose or galactose syrup. Laboratory scale processes for the production of fructose or galactose enriched syrups is now feasible, with important applications in food (like high fructose syrup as edulcorant) and fermentation technology (for GOS production).

Keywords: osmotolerant yeasts, selective metabolism, fructose syrup, GOS

Procedia PDF Downloads 449
41 Assessment of Seeding and Weeding Field Robot Performance

Authors: Victor Bloch, Eerikki Kaila, Reetta Palva

Abstract:

Field robots are an important tool for enhancing efficiency and decreasing the climatic impact of food production. There exists a number of commercial field robots; however, since this technology is still new, the robot advantages and limitations, as well as methods for optimal using of robots, are still unclear. In this study, the performance of a commercial field robot for seeding and weeding was assessed. A research 2-ha sugar beet field with 0.5m row width was used for testing, which included robotic sowing of sugar beet and weeding five times during the first two months of the growing. About three and five percent of the field were used as untreated and chemically weeded control areas, respectively. The plant detection was based on the exact plant location without image processing. The robot was equipped with six seeding and weeding tools, including passive between-rows harrow hoes and active hoes cutting inside rows between the plants, and it moved with a maximal speed of 0.9 km/h. The robot's performance was assessed by image processing. The field images were collected by an action camera with a height of 2 m and a resolution 27M pixels installed on the robot and by a drone with a 16M pixel camera flying at 4 m height. To detect plants and weeds, the YOLO model was trained with transfer learning from two available datasets. A preliminary analysis of the entire field showed that in the areas treated by the robot, the weed average density varied across the field from 6.8 to 9.1 weeds/m² (compared with 0.8 in the chemically treated area and 24.3 in the untreated area), the weed average density inside rows was 2.0-2.9 weeds / m (compared with 0 on the chemically treated area), and the emergence rate was 90-95%. The information about the robot's performance has high importance for the application of robotics for field tasks. With the help of the developed method, the performance can be assessed several times during the growth according to the robotic weeding frequency. When it’s used by farmers, they can know the field condition and efficiency of the robotic treatment all over the field. Farmers and researchers could develop optimal strategies for using the robot, such as seeding and weeding timing, robot settings, and plant and field parameters and geometry. The robot producers can have quantitative information from an actual working environment and improve the robots accordingly.

Keywords: agricultural robot, field robot, plant detection, robot performance

Procedia PDF Downloads 87
40 Being Authentic is the New “Pieces”: A Mixed Methods Study on Authenticity among African Christian Millennials

Authors: Victor Counted

Abstract:

Staying true to self is complicated. In most cases, we might not fully come to terms with this realities. Just like any journey, a self-discovery experience with the ‘self’, is like a rollercoaster ride. The researcher attempts to engage the reader in an empirical study on authenticity tendencies of African Christian Millennials. Hence, attempting the all-important question: What does it actually mean to be true to self for the African youth? A comprehensive, yet an unfinished business that applies the authenticity theory in its exploratory navigations to uncover the “lived world” of the participants who were part of this study. Using a mixed methods approach, the researcher will exhaustively give account to the authenticity tendencies and experiences of the respondents in the study by providing the reader with a unique narrative for understanding what it means to be true to oneself in Africa. At the quantitative study, the participants recorded higher scores on the Authenticity Scale (AS) authentic living, while showing a significant correlation within the subscales. Hypotheses were tested at the quantitative phase, which statistically supported gender and church affiliation as possible predictors for the authenticity orientations of the participants, while being a Christian native and race/ethnicity were not impact factors statistically. The results helped the researcher to develop the objectives behind the qualitative study, where only fifteen AS-authentic living participants were interviewed to understand why they scored high on authentic living, in order to understand what it means to be authentic. The hallmark of the qualitative case study exploration was the common coping mechanism of splitting adopted by the respondents to deal with their self-crisis as they tried to remain authentic to self, whilst self-regulating and self-investing the self to discover ‘self’. Specifically, the researcher observed the concurrent utilization of some kind of the religious-self by the respondents to regulate their self crisis, as they relate with self fragmenting through different splitting stages in hope for some kind of redemption. It was an explanation that led to the conclusion that being authentic is the new pieces. Authenticity is in fragments. This proposition led the researcher to introduce a hermeneutical support-system that will enable future researchers engage more critically and responsibly with their “living human documents” in order to inspire timely solutions that resolve the concerns of authenticity and wellbeing among Millennials in Africa.

Keywords: authenticity, self, identity, self-fragmentation, weak self integration, postmodern self, splitting

Procedia PDF Downloads 521
39 Elements of Critical Event Management: A Qualitative Study of Trauma Teams

Authors: Tan Xin Zhong Timothy, Chang Chen Jie Victor, Yew Kwan Tong, Lim Geok Peng Sandy

Abstract:

Background: Leaders in crisis response teams such as Trauma Teams in hospitals are essential to the effective coordination and direction of the team. The response to emergency trauma situations must be accurate, rapid, and well executed. To this end, the team leader’s social, technical and leadership skills are essential factors that implicate the success of an emergency trauma intervention. While each emergency trauma case varies in severity and complexity, and the experience and expertise of team leaders may vary, it would be productive to identify certain coordinative and directive functions that improve the capacity for leading a team. Methods: This qualitative study of Trauma Team physicians in Singapore General Hospital (SGH) involved 50 in-depth interviews with doctors and nurses involved in Trauma Team activations, observations of Trauma Teams managing emergency patients, and reviews of audio/video recordings of 65 trauma activations. The interviews were conducted with doctors of various ranks across the relevant departments, 12 from the Emergency Department (ED), 11 from General Surgery (GS) and 8 from Orthopaedics, while the 6 nurses were from ED. In accordance with the grounded theory approach, the content of the interviews was coded and analysed in order to derive broad leadership themes that corresponded with certain behavioural traits exhibited by trauma team leaders, supplemented with the observational and audio/video data. Results: The leadership behaviours of the team leaders could be typified into three broad categories: team orientation, engagement and activeness. Team orientation corresponds with the source and form of cognitive responsibility, decision-making and informational contributions, divisible into individualistic and consultative sub-categories. Engagement refers to the type of activity that leaders prefer to engage in, and which implicates their attentional focus, divisible into participatory and supervisory sub-categories. Activeness is a function of the leader’s attitudes towards the behavioural regulation of the team, which manifests in inactivity or activity to augment or merely align with protocol. These factors are not exhaustive and are contextually sensitive, but collectively implicate a significant portion of the leadership activity observed in trauma teams.

Keywords: trauma team activations, critical event management, leadership, teamwork

Procedia PDF Downloads 326
38 Aptamers: A Potential Strategy for COVID-19 Treatment

Authors: Mohamad Ammar Ayass, Natalya Griko, Victor Pashkov, Wanying Cao, Kevin Zhu, Jin Zhang, Lina Abi Mosleh

Abstract:

Respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for coronavirus disease 2019 (COVID-19). Early evidence pointed at the angiotensin-converting enzyme 2 (ACE-2) expressed on the epithelial cells of the lung as the main entry point of SARS-CoV-2 into the cells. The viral entry is mediated by the binding of the Receptor Binding Domain (RBD) of the spike protein that is expressed on the surface of the virus to the ACE-2 receptor. As the number of SARS-CoV-2 variants continues to increase, mutations arising in the RBD of SARS-CoV-2 may lead to the ineffectiveness of RBD targeted neutralizing antibodies. To address this limitation, the objective of this study is to develop a combination of aptamers that target different regions of the RBD, preventing the binding of the spike protein to ACE-2 receptor and subsequent viral entry and replication. A safe and innovative biomedical tool was developed to inhibit viral infection and reduce the harms of COVID-19. In the present study, DNA aptamers were developed against a recombinant trimer S protein using the Systematic Evolution of Ligands by Exponential enrichment (SELEX). Negative selection was introduced at round number 7 to select for aptamers that bind specifically to the RBD domain. A series of 9 aptamers (ADI2010, ADI2011, ADI201L, ADI203L, ADI205L, ADIR68, ADIR74, ADIR80, ADIR83) were selected and characterized with high binding affinity and specificity to the RBD of the spike protein. Aptamers (ADI25, ADI2009, ADI203L) were able to bind and pull down endogenous spike protein expressed on the surface of SARS-CoV-2 virus in COVID-19 positive patient samples and determined by liquid chromatography- tandem mass spectrometry analysis (LC-MS/MS). LC-MS/MS data confirmed that aptamers can bind to the RBD of the spike protein. Furthermore, results indicated that the combination of the 9 best aptamers inhibited the binding of the purified trimer spike protein to the ACE-2 receptor found on the surface of Vero E6 cells. In the same experiment, the combined aptamers displayed a better neutralizing effect than antibodies. The data suggests that the selected aptamers could be used in therapy to neutralize the effect of the SARS-CoV-2 virus by inhibiting the interaction between the RBD and ACE-2 receptor, preventing viral entry into target cells and therefore blocking viral replication.

Keywords: aptamer, ACE-2 receptor, binding inhibitor, COVID-19, spike protein, SARS-CoV-2, treatment

Procedia PDF Downloads 185