Search results for: Angel Romero MartíNez
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 394

Search results for: Angel Romero MartíNez

244 Verifying Environmental Performance through Inventory and Assessment: Case Study of the Los Alamos National Laboratory Waste Compliance and Tracking System

Authors: Oral S. Saulters, Shanon D. Goldberg, Wendy A. Staples, Ellena I. Martinez, Lorie M. Sanchez, Diego E. Archuleta, Deborah L. Williams, Scot D. Johnson

Abstract:

To address an important set of unverified field conditions, the Los Alamos National Laboratory Waste Compliance and Tracking System (WCATS) Wall-to-Wall Team performed an unprecedented and advanced inventory. This reconciliation involved confirmation analysis for approximately 5850 hazardous, low-level, mixed low-level, and transuranic waste containers located in more than 200 staging and storage areas across 33 technical areas. The interdisciplinary team scoped, planned, and developed the multidimensional assessments. Through coordination with cross-functional site hosts, they were able to verify and validate data while resolving discrepancies identified in WCATS. The results were extraordinary with an updated inventory, tailored outreach, more cohesive communications, and timely closed-loop feedback.

Keywords: circular economy, environmental performance data, social-ecological-technological systems, waste management

Procedia PDF Downloads 128
243 Distribution of Current Emerging Contaminants in South Africa Surface and Groundwater

Authors: Jou-An Chen, Julio Castillo, Errol Duncan Cason, Gabre Kemp, Leana Esterhuizen, Angel Valverde Portal, Esta Van Heerden

Abstract:

Emerging contaminants (EC) such as pharmaceutical and personal care products have been accumulating for years in water bodies all over the world. However, very little is known about the occurrences, levels, and effects of ECs in South African water resources. This study provides an initial assessment of the distribution of eight ECs (Acetaminophen, Atrazine, Terbuthlyazine, Carbamazepine, Phenyton, Sulfmethoxazole, Nevirapine and Fluconozole) in fifteen water sources from the Free State and Easter Cape provinces of South Africa. Overall, the physiochemical conditions were different in surface and groundwater samples, with concentrations of several elements such as B, Ca, Mg, Na, NO3, and TDS been statistically higher in groundwater. In contrast, ECs levels, quantified at ng/mL using the LC/MS/ESI, were much lower in groundwater samples. The ECs with higher contamination levels were Carbamazepine, Sulfmethoxazole, Nevirapine, and Terbuthlyazine, while the most widespread were Sulfmethoxazole and Fluconozole, detected in all surface and groundwater samples. Fecal and E. coli tests indicated that surface water was more contaminated than groundwater. Microbial communities, assessed using NGS, were dominated by the phyla Proteobacteria and Bacteroidetes, in both surface and groundwater. Actinobacteria, Planctomycetes, and Cyanobacteria, were more dominant in surface water, while Verrucomicrobia were overrepresented in groundwater. In conclusion, ECs contamination is closely associated with human activities (human wastes). The microbial diversity identified can suggest possible biodegradation processes.

Keywords: emerging contaminants, EC, personal care products, pharmaceuticals, natural attenuation process

Procedia PDF Downloads 219
242 The Effect of Si Content on the Physical Properties of Nanostructured (Ni75Fe25)100-xSix Alloy Elaborated by Mechanical Alloying

Authors: A. Kaibi, A. Guittoum, M. Hemmous, D. Martínez-Blanco, P. Gorria, J. A. Blanco, M. Kechouane

Abstract:

The present work deals with the effect of Si content on the physical properties of nanostructured (Ni75Fe25)100-x Six (x=0, 3.5, 6.5, 9, 12, and 15 at %) powders elaborated by mechanical alloying for a milling time of 96 h. The microstructure, hyperfine, and magnetic properties of the powders were investigated as a function of Si content by means of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Mössbauer Spectroscopy, and Vibrating Sample magnetometry (VSM). From XRD spectra, the formation of FCC disordered Ni (Fe,Si) solid solution was evidenced after 96 h. As Si content increases, the lattice parameter and the grain size decrease (from ~28 to 15 nm), while the microstrain level decreases from 0.98% to 0.65%. From SEM micrographs, we showed that powder particles become round in shape and decrease in size with increasing Si content. For all Si content, the adjustment of Mössbauer spectra confirmed the formation of a disordered ferromagnetic NiFeSi phase. From hysteresis curves, we have extracted the values of saturation magnetization and coercive field for all powders. The evolution of Ms and Hc as a function of Si content will be discussed.

Keywords: nanostructured powders, (Ni75Fe25)100-xSix alloy, microstructure, magnetic properties

Procedia PDF Downloads 31
241 D6tions: A Serious Game to Learn Software Engineering Process and Design

Authors: Hector G. Perez-Gonzalez, Miriam Vazquez-Escalante, Sandra E. Nava-Muñoz, 
 Francisco E. Martinez-Perez, Alberto S. Nunez-Varela

Abstract:

The software engineering teaching process has been the subject of many studies. To improve this process, researchers have proposed merely illustrative techniques in the classroom, such as topic presentations and dynamics between students on one side or attempts to involve students in real projects with companies and institutions to bring them to a real software development problem on the other hand. Simulators and serious games have been used as auxiliary tools to introduce students to topics that are too abstract when these are presented in the traditional way. Most of these tools cover a limited area of the huge software engineering scope. To address this problem, we have developed D6tions, an educational serious game that simulates the software engineering process and is designed to experiment the different stages a software engineer (playing roles as project leader or as a developer or designer) goes through, while participating in a software project. We describe previous approaches to this problem, how D6tions was designed, its rules, directions, and the results we obtained of the use of this game involving undergraduate students playing the game.

Keywords: serious games, software engineering, software engineering education, software engineering teaching process

Procedia PDF Downloads 494
240 Disadvantaged Adolescents and Educational Delay in South Africa: Impacts of Personal, Family, and School Characteristics

Authors: Rocio Herrero Romero, Lucie Cluver, James Hall, Janina Steinert

Abstract:

Educational delay and non-completion are major policy concerns in South Africa. However, little research has focused on predictors for educational delay amongst adolescents in disadvantaged areas. This study has two aims: first, to use data integration approaches to compare the educational delay of 599 adolescents aged 16 to 18 from disadvantaged communities to national and provincial representative estimates in South Africa. Second, the paper also explores predictors for educational delay by comparing adolescents out of school (n=64) and at least one year behind (n=380), with adolescents in the age-appropriate grade or higher (n=155). Multinomial logistic regression models using self-report and administrative data were applied to look for significant associations of risk and protective factors. Significant risk factors for being behind (rather than in age-appropriate grade) were: male gender, past grade repetition, rural location and larger school size. Risk factors for being out of school (rather than in the age-appropriate grade) were: past grade repetition, having experienced problems concentrating at school, household poverty, and food insecurity. Significant protective factors for being in the age-appropriate grade (rather than out of school) were: living with biological parents or grandparents and access to school counselling. Attending school in wealthier communities was a significant protective factor for being in the age-appropriate grade (rather than behind). Our results suggest that both personal and contextual factors –family and school- predicted educational delay. This study provides new evidence to the significant effects of personal, family, and school characteristics on the educational outcomes of adolescents from disadvantaged communities in South Africa. This is the first longitudinal and quantitative study to systematically investigate risk and protective factors for post-compulsory educational outcomes amongst South African adolescents living in disadvantaged communities.

Keywords: disadvantaged communities, quantitative analysis, school delay, South Africa

Procedia PDF Downloads 349
239 Perception of Violence through the Drawing: A Research with Mexican University Students

Authors: Yessica Martinez Soto, Cesar E. Jimenez Yanez, Margarita Barak Velasquez, Yaralin Aceves Villanueva

Abstract:

The presence of violent behavior in society is growing rapidly, which causes people to live in an environment of constant tension due to fear of becoming victims of violent acts. It is up to social scientists to be able to carry out analyzes in this regard to identify the different ways in which violence is normalized among people. The interest of this research work focuses on investigating the perception of violence in Mexican University students through the technique of drawing. To carry out this research, we worked with 67 university students from the Autonomous University of Baja California in Mexico, who drew an image of how they understood the concept of violence. His works showed us a variety of emotions, actions, and elements that relate and link with violence. One of the methodological tools to recognize and establish the link between the knowledge of a concept between discourse and practice is through graphic representations, that is, drawings. Although the drawing gives us a personal interpretation of the reality of each artist, the repetition of elements and the representation of similar situations allowed us to identify the degrees of incidence of the different types of violence and the areas in which it manifests itself.

Keywords: college students, Mexico, social representations, violence

Procedia PDF Downloads 234
238 Nutritional Properties and Lipid Oxidation Assessments of Sucuks Prepared with Camel (Camelus Dromedarius) Meat and Hump

Authors: Mina Kargozari, Isabel Revilla Martin, Ángel A. Carbonell-Barrachina

Abstract:

Different formulations of Turkish fermented sausages (sucuks) prepared with camel meat-hump (CH), camel meat-beef fat (CB), beef-hump (BH) and beef-beef fat (BB), were characterized. The sausages were analytically compared to determine differences in proximate composition and total cholesterol content (TCC), quality parameters such as fatty acids profile and fat quality characteristics, and lipid oxidation parameters including peroxide value, thiobarbituric acid-reactive substances (TBARS) and resulted carbonyl compounds. The PUFAs/SFAs ratio was higher in CB and BB samples than CH and BH (p<0.05). The higher calculated atherogenic and thrombogenic indexes (AI and TI) were obtained from the samples made with hump (p< 0.05) as a result of high amounts of their SFAs. The CH sausages contained high amount of total fat (p<0.05) among all samples. The CB sucuks exhibited the highest protein content and the lowest TCC and rancidity at the end of ripening (p<0.05). The TBARS results showed that beef fat samples were more susceptible to lipid oxidation. Moreover, no significant difference (p<0.05) was observed for the values of short aldehydes among the sucuk samples excepting nonanal. This study demonstrated that supplementing camel meat for the production of dry-fermented sausage resulted in high quality products with good functional and nutritional characteristics.

Keywords: fermented sausages, quality properties, SPME, total cholesterol content

Procedia PDF Downloads 325
237 Comparison Of Data Mining Models To Predict Future Bridge Conditions

Authors: Pablo Martinez, Emad Mohamed, Osama Mohsen, Yasser Mohamed

Abstract:

Highway and bridge agencies, such as the Ministry of Transportation in Ontario, use the Bridge Condition Index (BCI) which is defined as the weighted condition of all bridge elements to determine the rehabilitation priorities for its bridges. Therefore, accurate forecasting of BCI is essential for bridge rehabilitation budgeting planning. The large amount of data available in regard to bridge conditions for several years dictate utilizing traditional mathematical models as infeasible analysis methods. This research study focuses on investigating different classification models that are developed to predict the bridge condition index in the province of Ontario, Canada based on the publicly available data for 2800 bridges over a period of more than 10 years. The data preparation is a key factor to develop acceptable classification models even with the simplest one, the k-NN model. All the models were tested, compared and statistically validated via cross validation and t-test. A simple k-NN model showed reasonable results (within 0.5% relative error) when predicting the bridge condition in an incoming year.

Keywords: asset management, bridge condition index, data mining, forecasting, infrastructure, knowledge discovery in databases, maintenance, predictive models

Procedia PDF Downloads 191
236 Hydrodeoxygenation of Furfural over RU Sub-Nano Particles Supported on Al₂O₃-SIO₂ Mixed Oxides

Authors: Chaima Zoulikha Tabet Zatla, Nihel Dib, Sumeya Bedrane, Juan Carlos Hernandez Garrido, Redouane Bachir, Miguel Angel Cauqui, Jose Juan Calvino Gamez

Abstract:

These last year's our planet has witnessed global warming, which is a serious threat to our lives; it has many causes, such as the CO₂ excess in the atmosphere that results from our activity, for the purpose of living in a neater and better environment, working and improving an eco-responsible energy system is a must. Valorization of biomass to produce biofuels is among the most compelling routes to decrease air pollution without considerable modification in current vehicle technology. Effective transformation of lignocellulosic biomass-derived compounds into liquid fuels and value-added chemicals is an economically viable solution. Presently, very competitive technics for the conversion of lignocellulosic biomass into platform chemicals, such as furfural and Hydroxymethylfurfural (HMF), are used. Furfural (C₅H₄O₂) is a major hemi cellulosic biomass-derived platform molecule. In our work, we focus on the valorization of lignocellulosic biomass derivative furfural that is transformed into biofuel through a hydrodeoxygenation reaction in general and involving a catalytic process. In order to get to this point, we are synthesizing and characterizing a series of catalysts with different amounts of Ru (0.5%, 1% and 2%) supported on alumina-silica mixed oxides with various molar ratios (Si/Al = 2.5; 5; 7; 10; 15). These catalysts will be characterized by numerous technics such as N₂ adsorption/desorption, Pyridine adsorption (acidity measure), FTIR, X-rays diffraction, AAS, TEM and SEM.

Keywords: furfural, ruthenium, silica-alumina, biomass, biofuel

Procedia PDF Downloads 85
235 Quantification of Enzymatic Activities of Proteins, Peroxidase and Phenylalanine Ammonia Lyase, in Growing Phaseolus vulgaris L, with Application Bacterial Consortium to Control Fusarium and Rhizoctonia

Authors: Arredondo Valdés Roberto, Hernández Castillo Francisco Daniel, Laredo Alcalá Elan Iñaky, Gonzalez Gallegos Esmeralda, Castro Del Angel Epifanio

Abstract:

The common bean or Phaseolus vulgaris L. is the most important food legume for direct consumption in the world. Fusarium dry rot in the major fungus disease affects Phaseolus vulgaris L, after planting. In another hand, Rhizoctonia can be found on all underground parts of the plant and various times during the growing season. In recent years, the world has conducted studies about the use of natural products as substitutes for herbicides and pesticides, because of possible ecological and economic benefits. Plants respond to fungal invasion by activating defense responses associated with accumulation of several enzymes and inhibitors, which prevent pathogen infection. This study focused on the role of proteins, peroxidase (POD), phenylalanine ammonia lyase (PAL), in imparting resistance to soft rot pathogens by applied different bacterial consortium, formulated and provided by Biofertilizantes de Méxicanos industries, analyzing the enzyme activity at different times of application (6 h, 12 h and 24 h). The resistance of these treatments was correlated with high POD and PAL enzyme activity as well as increased concentrations of proteins. These findings show that PAL, POD and synthesis of proteins play a role in imparting resistance to Phaseolus vulgaris L. soft rot infection by Fusarium and Rhizoctonia.

Keywords: fusarium, peroxidase, phenylalanine ammonia lyase, rhizoctonia

Procedia PDF Downloads 353
234 Competition Between the Effects of Pesticides and Immune-activation on the Expression of Toll Pathway Genes

Authors: Dani Sukkar, Ali Kanso, Philippe Laval-Gilly, Jairo Falla-Angel

Abstract:

The honeybees' immune system is challenged by different risk factors that induce various responses. However, complex scenarios where bees are exposed to different pesticides simultaneously with immune activation are not well evaluated. The Toll pathway is one of the main signaling pathways studied in invertebrate immune responses, and it is a good indicator of the effect of such complex interactions in addition to key signaling elements of other pathways like Relish of the immune deficiency (IMD) pathway or Eater, the phagocytosis receptor or vitellogenin levels. Honeybee hemocytes extracted from 5th instar larvae were exposed to imidacloprid and/or amitraz with or without the presence of the zymosan a as an immune activator. The gene expression of multiple immune related genes were studied, including spaetzle, Toll, myD88, relish, eater and vitellogenin, by real-time polymerase chain reaction after RNA extraction. The results demonstrated that the Toll pathway is mainly affected by the pesticides; imidacloprid and amitraz, especially by their different combinations. Furthermore, immune activation by zymosan A, a fungal cell-wall component, acts to mitigate to some extent the effect of pesticides on the different levels of the Toll pathway. In addition, imidacloprid, amitraz, and zymosan A have complex and context-specific interactions depending on the levels of immune activation and the pathway evaluated affecting immune-gene expression differently.

Keywords: toll pathway, immune modulation, β-glucan, imidacloprid, amitraz, honeybees, immune genes

Procedia PDF Downloads 89
233 Understanding Evolutionary Algorithms through Interactive Graphical Applications

Authors: Javier Barrachina, Piedad Garrido, Manuel Fogue, Julio A. Sanguesa, Francisco J. Martinez

Abstract:

It is very common to observe, especially in Computer Science studies that students have difficulties to correctly understand how some mechanisms based on Artificial Intelligence work. In addition, the scope and limitations of most of these mechanisms are usually presented by professors only in a theoretical way, which does not help students to understand them adequately. In this work, we focus on the problems found when teaching Evolutionary Algorithms (EAs), which imitate the principles of natural evolution, as a method to solve parameter optimization problems. Although this kind of algorithms can be very powerful to solve relatively complex problems, students often have difficulties to understand how they work, and how to apply them to solve problems in real cases. In this paper, we present two interactive graphical applications which have been specially designed with the aim of making Evolutionary Algorithms easy to be understood by students. Specifically, we present: (i) TSPS, an application able to solve the ”Traveling Salesman Problem”, and (ii) FotEvol, an application able to reconstruct a given image by using Evolution Strategies. The main objective is that students learn how these techniques can be implemented, and the great possibilities they offer.

Keywords: education, evolutionary algorithms, evolution strategies, interactive learning applications

Procedia PDF Downloads 338
232 Antiproliferative Effect of Polyphenols from Crocus sativus L. Leaves on Human Colon Adenocarcinoma Cells (Caco-2)

Authors: Gonzalo Ortiz de Elguea-Culebras, Raúl Sánchez-Vioquea, Adela Mena-Morales, Manuel Alaiz, Enrique Melero-Bravo, Esteban García-Romero, Javier Vioque, Lourdes Marchante-Cuevas, Julio Girón-Calle

Abstract:

Saffron (Crocus sativus L.) is a highly valued crop for the manufacture of spice that consists of the dried stigma of the flowers. This is in contrast to other underutilized parts of the saffron plant as leaves, which represent abundant biomass whose use might help to enhance the sustainability of the saffron crop. Saffron leaves contain significant amounts of phenolic compounds, 7.8 equivalent grams of gallic acid per 100g of extract, and are very promising compounds in terms of exploring novel uses of saffron leaves. Given that phenolic compounds have numerous effects on cancer-related biological pathways, we have investigated the in vitro antiproliferative effect of saffron leaf polyphenols against human colon adenocarcinoma cells (Caco-2). Polyphenols were extracted from leaves with 70% ethanol, defatted with hexane, and purified by solid phase extraction using C18 silica gel and then silica gel 60. Analysis of polyphenols was performed by HPLC-ESI-MS. Di-, tri-, and tetrahexosides of quercetin, kaempferol, and isorhamnetin, as well as C-hexosides like isoorientin and vitexin, were tentatively identified. Polyphenols strongly inhibited the proliferation of Caco-2 cells, which is consistent with model studies in which several of the polyphenols identified in saffron leaves have demonstrated their potential as chemopreventive agents in cancer. Due to the low profitability that saffron leaf currently represents, we consider these results very encouraging and that this by-product deserves further investigation as a potential source of active molecules against colorectal cancer.

Keywords: saffron leaves, agricultural by-products, polyphenols, antiproliferative effect, human colon adenocarcinoma cells

Procedia PDF Downloads 96
231 Calibration of Resistance Factors for Reliability-Based Design of Driven Piles Considering Unsaturated Soil Effects

Authors: Mohammad Amin Tutunchian, Pedram Roshani, Reza Rezvani, Julio Ángel Infante Sedano

Abstract:

The highly recommended approach to design, known as the load and resistance factor design (LRFD) method, employs the geotechnical resistance factor (GRF) for shaping pile foundation designs. Within the standard process for designing pile foundations, geotechnical engineers commonly adopt a design strategy rooted in saturated soil mechanics (SSM), often disregarding the impact of unsaturated soil behavior. This oversight within the design procedure leads to the omission of the enhancement in shear strength exhibited by unsaturated soils, resulting in a more cautious outcome in design results. This research endeavors to present a methodology for fine-tuning the GRF used for axially loaded driven piles in Winnipeg, Canada. This is achieved through the application of a well-established probabilistic approach known as the first-order second moment (FOSM) method while also accounting for the influence of unsaturated soil behavior. The findings of this study demonstrate that incorporating the influence of unsaturated conditions yields an elevation in projected bearing capacity and recommends higher GRF values in accordance with established codes. Additionally, a novel factor referred to as phy has been introduced to encompass the impact of saturation conditions in the calculation of pile bearing capacity, as guided by prevalent static analysis techniques.

Keywords: unsaturated soils, shear strength, LRFD, FOSM, GRF

Procedia PDF Downloads 89
230 Image Processing Approach for Detection of Three-Dimensional Tree-Rings from X-Ray Computed Tomography

Authors: Jorge Martinez-Garcia, Ingrid Stelzner, Joerg Stelzner, Damian Gwerder, Philipp Schuetz

Abstract:

Tree-ring analysis is an important part of the quality assessment and the dating of (archaeological) wood samples. It provides quantitative data about the whole anatomical ring structure, which can be used, for example, to measure the impact of the fluctuating environment on the tree growth, for the dendrochronological analysis of archaeological wooden artefacts and to estimate the wood mechanical properties. Despite advances in computer vision and edge recognition algorithms, detection and counting of annual rings are still limited to 2D datasets and performed in most cases manually, which is a time consuming, tedious task and depends strongly on the operator’s experience. This work presents an image processing approach to detect the whole 3D tree-ring structure directly from X-ray computed tomography imaging data. The approach relies on a modified Canny edge detection algorithm, which captures fully connected tree-ring edges throughout the measured image stack and is validated on X-ray computed tomography data taken from six wood species.

Keywords: ring recognition, edge detection, X-ray computed tomography, dendrochronology

Procedia PDF Downloads 221
229 Application of the Critical Decision Method for Monitoring and Improving Safety in the Construction Industry

Authors: Juan Carlos Rubio Romero, Francico Salguero Caparros, Virginia Herrera-Pérez

Abstract:

No one is in the slightest doubt about the high levels of risk involved in work in the construction industry. They are even higher in structural construction work. The Critical Decision Method (CDM) is a semi-structured interview technique that uses cognitive tests to identify the different disturbances that workers have to deal with in their work activity. At present, the vision of safety focused on daily performance and things that go well for safety and health management is facing the new paradigm known as Resilience Engineering. The aim of this study has been to describe the variability in formwork labour on concrete structures in the construction industry and, from there, to find out the resilient attitude of workers to unexpected events that they have experienced during their working lives. For this purpose, a series of semi-structured interviews were carried out with construction employees with extensive experience in formwork labour in Spain by applying the Critical Decision Method. This work has been the first application of the Critical Decision Method in the field of construction and, more specifically, in the execution of structures. The results obtained show that situations categorised as unthought-of are identified to a greater extent than potentially unexpected situations. The identification during these interviews of both expected and unexpected events provides insight into the critical decisions made and actions taken to improve resilience in daily practice in this construction work. From this study, it is clear that it is essential to gain more knowledge about the nature of the human cognitive process in work situations within complex socio-technical systems such as construction sites. This could lead to a more effective design of workplaces in the search for improved human performance.

Keywords: resilience engineering, construction industry, unthought-of situations, critical decision method

Procedia PDF Downloads 148
228 Embracing Circular Economy: Unlocking Sustainable Growth in Emerging Markets

Authors: Mario Jose Paillacho Silva, José Ángel Pérez López

Abstract:

This article delves into the critical role of circular economy principles in unlocking sustainable growth and addressing environmental inequalities in emerging markets. Circular economy practices, rooted in regenerative systems and resource conservation, offer a transformative pathway for dynamic economies to achieve prosperity while minimizing environmental impact. The article comprehensively explores the understanding of the circular economy in emerging markets, emphasizing its economic benefits, social implications, and environmental advantages. It highlights key challenges and opportunities faced by these markets and emphasizes the crucial role of governments in creating supportive policy frameworks. It emphasizes how circular economy practices empower local communities and promote social inclusion and equality. Furthermore, the article underscores how the adoption of circular economy practices can mitigate waste, pollution, and resource scarcity, thus contributing to climate change mitigation and adaptation. Integrating circular economy principles with the United Nations' sustainable development goals (SDGs), the article showcases the potential of circularity in fostering responsible consumption and production, sustainable economic growth, and environmental protection. Overall, the article advocates for cross-sector collaboration and knowledge sharing to overcome barriers and scale circular economy practices in emerging markets, ultimately leading to a more equitable, prosperous, and environmentally sustainable future.

Keywords: circular economy, sustainability, emerging markets, circularity

Procedia PDF Downloads 82
227 Towards the Enhancement of Thermoelectric Properties by Controlling the Thermoelectrical Nature of Grain Boundaries in Polycrystalline Materials

Authors: Angel Fabian Mijangos, Jaime Alvarez Quintana

Abstract:

Waste heat occurs in many areas of daily life because world’s energy consumption is inefficient. In general, generating 1 watt of power requires about 3 watt of energy input and involves dumping into the environment the equivalent of about 2 watts of power in the form of heat. Therefore, an attractive and sustainable solution to the energy problem would be the development of highly efficient thermoelectric devices which could help to recover this waste heat. This work presents the influence on the thermoelectric properties of metallic, semiconducting, and dielectric nanoparticles added into the grain boundaries of polycrystalline antimony (Sb) and bismuth (Bi) matrixes in order to obtain p- and n-type thermoelectric materials, respectively, by hot pressing methods. Results show that thermoelectric properties are significantly affected by the electrical and thermal nature as well as concentration of nanoparticles. Nevertheless, by optimizing the amount of the nanoparticles on the grain boundaries, an oscillatory behavior in ZT as function of the concentration of the nanoscale constituents is present. This effect is due to energy filtering mechanism which module the quantity of charge transport in the system and affects thermoelectric properties. Accordingly, a ZTmax can be accomplished through the addition of the appropriate amount of nanoparticles into the grain boundaries region. In this case, till three orders of amelioration on ZT is reached in both systems compared with the reference sample of each one. This approach paves the way to pursuit high performance thermoelectric materials in a simple way and opens a new route towards the enhancement of the thermoelectric figure of merit.

Keywords: energy filtering, grain boundaries, thermoelectric, nanostructured materials

Procedia PDF Downloads 255
226 Use of the Occupational Repetitive Action Method in Different Productive Sectors: A Literature Review 2007-2018

Authors: Aanh Eduardo Dimate-Garcia, Diana Carolina Rodriguez-Romero, Edna Yuliana Gonzalez Rincon, Diana Marcela Pardo Lopez, Yessica Garibello Cubillos

Abstract:

Musculoskeletal disorders (MD) are the new epidemic of chronic diseases, are multifactorial and affect the different productive sectors. Although there are multiple instruments to evaluate the static and dynamic load, the method of repetitive occupational action (OCRA) seems to be an attractive option. Objective: It is aimed to analyze the use of the OCRA method and the prevalence of MD in workers of various productive sectors according to the literature (2007-2018). Materials and Methods: A literature review (following the PRISMA statement) of studies aimed at assessing the level of biomechanical risk (OCRA) and the prevalence of MD in the databases Scielo, Science Direct, Scopus, ProQuest, Gale, PubMed, Lilacs and Ebsco was realized; 7 studies met the selection criteria; the majority are quantitative (cross section). Results: it was evidenced (gardening and flower-growers) in this review that 79% of the conditions related to the task require physical requirements and involve repetitive movements. In addition, of the high appearance of DM in the high-low back, upper and lower extremities that are produced by the frequency of the activities carried out (footwear production). Likewise, there was evidence of 'very high risks' of developing MD (salmon industry) and a medium index (OCRA) for repetitive movements that require special care (U-Assembly line). Conclusions: the review showed the limited use of the OCRA method for the detection of MD in workers from different sectors, and this method can be used for the detection of biomechanical risk and the appearance of MD.

Keywords: checklist, cumulative trauma disorders, musculoskeletal diseases, repetitive movements

Procedia PDF Downloads 182
225 Website Appeal’s Impact on Brand Outcomes: The Mediated Effect of Emotional Attractiveness in the Relationship between Consistent Image and Brand Value

Authors: Salvador Treviño-Martinez, Christian Reich-Lopez

Abstract:

This paper investigates the relationship between website appeal and brand value outcomes (brand attraction, brand loyalty, brand relationship, and brand experience), considering the mediating effect of emotional attractiveness. Data were collected from 221 customers of a quick-service restaurant in Culiacan, Mexico, using an online survey distributed via WhatsApp, following the clients' navigation of the restaurant's website. The study employed PLS-SEM to test the proposed hypotheses and performed 5,000 bootstrapping subsamples to obtain results. The findings indicate that consistent image, a key component of website appeal, has a statistically significant direct and mediated effect (through emotional attractiveness) on the aforementioned brand outcomes. The study's limitations include the convenience sampling method and the single company client database used for the sample composition. This research contributes to the branding and website quality literature by testing nine hypotheses using the Stimuli-Organism-Response theoretical approach in an underexplored context: quick-service restaurants in Latin America.

Keywords: website appeal, branding, emotional attractiveness, consistent image, website quality

Procedia PDF Downloads 93
224 Urinalysis by Surface-Enhanced Raman Spectroscopy on Gold Nanoparticles for Different Disease

Authors: Leonardo C. Pacheco-Londoño, Nataly J. Galan-Freyle, Lisandro Pacheco-Lugo, Antonio Acosta, Elkin Navarro, Gustavo Aroca-Martínez, Karin Rondón-Payares, Samuel P. Hernández-Rivera

Abstract:

In our Life Science Research Center of the University Simon Bolivar (LSRC), one of the focuses is the diagnosis and prognosis of different diseases; we have been implementing the use of gold nanoparticles (Au-NPs) for various biomedical applications. In this case, Au-NPs were used for Surface-Enhanced Raman Spectroscopy (SERS) in different diseases' diagnostics, such as Lupus Nephritis (LN), hypertension (H), preeclampsia (PC), and others. This methodology is proposed for the diagnosis of each disease. First, good signals of the different metabolites by SERS were obtained through a mixture of urine samples and Au-NPs. Second, PLS-DA models based on SERS spectra to discriminate each disease were able to differentiate between sick and healthy patients with different diseases. Finally, the sensibility and specificity for the different models were determined in the order of 0.9. On the other hand, a second methodology was developed using machine learning models from all data of the different diseases, and, as a result, a discriminant spectral map of the diseases was generated. These studies were possible thanks to joint research between two university research centers and two health sector entities, and the patient samples were treated with ethical rigor and their consent.

Keywords: SERS, Raman, PLS-DA, diseases

Procedia PDF Downloads 143
223 Evaluation of the Curricular Content Domain Related to Topics of Human Sexuality in Teachers of Public Elementary Schools

Authors: Ahmed Ali Asadi, Julio R. Martinez-Alvarado, Claudia V. Camacho-Guevara, J. Jesus Cabrales-Ruvalcaba, Julieta Y. Islas-Limon, Bertha M. Viñas-Velazquez

Abstract:

The transformation of education in Mexico incorporates human sexuality subjects in its study plans for elementary education level, leaving aside the training of teachers to educate on such topics. The objective of this study was to evaluate the curricular content domain related to human sexuality subjects of public elementary school teachers in Mexico. For this, a transversal descriptive-prospective study with a quantitative focus has been conducted. The population for this study consisted of 109 fifth and sixth-grade teachers from a school zone of the State Education System. It was found in the results that fifth-grade teachers got a low achievement level, sixth-grade teachers got a medium achievement level, while teachers who give classes on both grades obtained a high achievement level on domain of curricular subjects related to sexuality. Likewise, a relation of different variables with the participant’s achievement level is exposed.

Keywords: curricular content, evaluation, sexual education, teacher

Procedia PDF Downloads 296
222 On the Causes of Boko Haram Terrorism: Socio-Economic versus Religious Injunctions

Authors: Sogo Angel Olofinbiyi

Abstract:

There have been widespread assumptions across the globe that the root cause of Boko Haram terrorism in Nigeria is religious rather than socio-economic. An investigation into this dichotomy allowed this study to fully demonstrate that the root cause of Boko Haram’s terrorist actions emanates from the non-fulfillment of socio-economic goals that are prompted by the violation of fundamental human rights, corruption, poverty, unconstitutional and undemocratic practices in the northern part of the Nigerian state. To achieve its aim of establishing the root cause of the terrorism crisis in the latter country, the study critically appraised the socio-economic context of the insurgency by adopting one-on-one in-depth interviews involving forty (40) participants to interrogate the phenomenon. Empirical evidence from the study demonstrated that the evolution of Boko Haram terrorism was a response to socio-economic phlebotomy, political and moral putrescence, and the dehumanization of people that stem from a combination of decades of mismanagement and pervasive corruption by various Nigerian leaders. The study concludes that, as long as the endemic socio-economic problems caused by global capitalism vis-a-vis unequal hegemonic power exchange as expressed in socio-political, ethno-religious and cultural forms persist in the Nigerian society, the terrorism insurgency will recur and remain an inevitable enterprise and indeed a normal social reaction to every undesirable state of affairs. Based on the findings, the study urges the need for the amelioration of the conditions of the vast majority of the Nigerian populace by making socio-economic facilities available to them through the political state.

Keywords: Boko Haram Terrorism, insurgency, socio-economic, religious injunctions

Procedia PDF Downloads 186
221 Debt Portfolios of the Poor: The Case of Street Vendors in Cali, Colombia

Authors: Lina Martinez, Juan David Rivera Acevedo, Isabella Franco

Abstract:

The informal economy plays a significant role in the job market in Colombia. Cali, the third largest city in the country, is characterized by a high percentage of socially and economically vulnerable population groups who take part in the urban informal economy, with street vending as their primary source of income. This paper studies the socio-economic dimensions of street vendors in Cali. In particular, it examines why they are unable to capitalize on their comparatively high earnings and are not likely to escape poverty even though they usually profit from government welfare and tax evasion due to the non-regulated character of informality. The analysis of an observational study and two surveys with 637 and 300 participants show that street vending is a cash-based day-to-day activity. Since most of the street vendors do not have access to formal banking systems, they depend on payday loans with incomparably high interest rates which absorb a large share of their income and maintain a continuous indebtedness. This is one of the main reasons why they are unable to improve their living conditions. However, the daily cash flow masks the high opportunity cost of loans and long-term deficits.

Keywords: Colombia, informal economy, payday loans, street vendors

Procedia PDF Downloads 324
220 Analysis of Vocal Pathologies Through Subglottic Pressure Measurement

Authors: Perla Elizabeth Jimarez Rocha, Carolina Daniela Tejeda Franco, Arturo Minor Martínez, Annel Gomez Coello

Abstract:

One of the biggest problems in developing new therapies for the management and treatment of voice disorders is the difficulty of objectively evaluating the results of each treatment. A system was proposed that captures and records voice signals, in addition to analyzing the vocal quality (fundamental frequency, zero crossings, energy, and amplitude spectrum), as well as the subglottic pressure (cm H2O) during the sustained phonation of the vowel / a /; a recording system is implemented, as well as an interactive system that records information on subglottic pressure. In Mexico City, a control group of 31 patients with phoniatric pathology is proposed; non-invasive tests were performed for these most common vocal pathologies (Nodules, Polyps, Irritative Laryngitis, Ventricular Dysphonia, Laryngeal Cancer, Dysphonia, and Dysphagia). The most common pathology was irritative laryngitis (32%), followed by vocal fold paralysis (unilateral and bilateral,19.4 %). We take into consideration men and women in the pathological groups due to the physiological difference. They were separated in gender by the difference in the morphology of the respiratory tract.

Keywords: amplitude spectrum, energy, fundamental frequency, subglottic pressure, zero crossings

Procedia PDF Downloads 122
219 WSN System Warns Atta Cephalotes Climbing in Mango Fruit Trees

Authors: Federico Hahn Schlam, Fermín Martínez Solís

Abstract:

Leaf-cutting ants (Atta cephalotes) forage from mango tree leaves and flowers to feed their colony. Farmers find it difficult to control ants due to the great quantity of trees grown in commercial orchards. In this article, IoT can support farmers for ant detection in real time, as production losses can be considered of 324 US per tree.A wireless sensor network, WSN, was developed to warn the farmer from ant presence in trees during a night. Mango trees were gathered into groups of 9 trees, where the central tree holds the master microcontroller, and the other eight trees presented slave microcontrollers (nodes). At each node, anemitter diode-photodiode unitdetects ants climbing up. A capacitor is chargedand discharged after being sampled every ten minutes. The system usesBLE (Bluetooth Low Energy) to communicate between the master microcontroller by BLE.When ants were detected the number of the tree was transmitted via LoRa from the masterto the producer smartphone to warn him. In this paper, BLE, LoRa, and energy consumption were studied under variable vegetation in the orchard. During 2018, 19 trees were attacked by ants, and ants fed 26.3% of flowers and 73.7% of leaves.

Keywords: BLE, atta cephalotes, LoRa, WSN-smartphone, energy consumption

Procedia PDF Downloads 159
218 Environmental Study on Urban Disinfection Using an On-site Generation System

Authors: Víctor Martínez del Rey, Kourosh Nasr Esfahani, Amir Masoud Samani Majd

Abstract:

In this experimental study, the behaviors of Mixed Oxidant solution components (MOS) and sodium hypochlorite (HYPO) as the most commonly applied surface disinfectant were compared through the effectiveness of chlorine disinfection as a function of the contact time and residual chlorine. In this regard, the variation of pH, free available chlorine (FAC) concentration, and electric conductivity (EC) of disinfection solutions in different concentrations were monitored over 48 h contact time. In parallel, the plant stress activated by chlorine-based disinfectants was assessed by comparing MOS and HYPO. The elements of pH and EC in the plant-soil and their environmental impacts, spread by disinfection solutions were analyzed through several concentrations of FAC including 500 mg/L, 1000 mg/L, and 5000 mg/L in irrigated water. All the experiments were carried out at the service station of Sant Cugat, Spain. The outcomes indicated lower pH and higher durability of MOS than HYPO at the same concentration of FAC which resulted in promising stability of FAC within MOS. Furthermore, the pH and EC value of plant-soil irrigated by NaOCl solution were higher than that of MOS solution at the same FAC concentration. On-site generation of MOS as a safe chlorination option might be considered an imaginary future of smart cities.

Keywords: disinfection, free available chlorine, on-site generation, sodium hypochlorite

Procedia PDF Downloads 118
217 Critical Evaluation of Groundwater Monitoring Networks for Machine Learning Applications

Authors: Pedro Martinez-Santos, Víctor Gómez-Escalonilla, Silvia Díaz-Alcaide, Esperanza Montero, Miguel Martín-Loeches

Abstract:

Groundwater monitoring networks are critical in evaluating the vulnerability of groundwater resources to depletion and contamination, both in space and time. Groundwater monitoring networks typically grow over decades, often in organic fashion, with relatively little overall planning. The groundwater monitoring networks in the Madrid area, Spain, were reviewed for the purpose of identifying gaps and opportunities for improvement. Spatial analysis reveals the presence of various monitoring networks belonging to different institutions, with several hundred observation wells in an area of approximately 4000 km2. This represents several thousand individual data entries, some going back to the early 1970s. Major issues included overlap between the networks, unknown screen depth/vertical distribution for many observation boreholes, uneven time series, uneven monitored species, and potentially suboptimal locations. Results also reveal there is sufficient information to carry out a spatial and temporal analysis of groundwater vulnerability based on machine learning applications. These can contribute to improve the overall planning of monitoring networks’ expansion into the future.

Keywords: groundwater monitoring, observation networks, machine learning, madrid

Procedia PDF Downloads 79
216 Study of the Influence of the Different Treatments in Almond Shell-Based Masterbatches

Authors: A. Ibáñez, A. Martínez, A. Sánchez, M. A. León

Abstract:

This article is focused on the development of a series of biodegradable and eco-friendly masterbatches based on polylactic acid (PLA) filled with almond shell to study the influence of almond shell in the properties of injected biodegradable parts. These innovative masterbatches have 20 wt % of the almond shell. Different treatments were carried out with sodium hydroxide (NaOH) and maleic anhydride (MA) to obtain better interfacial bonding between fibre and matrix. The masterbatches were produced by varying the fibre treatments (type of treatment, concentration and temperature). The masterbatches have been injected to obtain standardised test samples in order to study mechanical properties. The results show that, the some of the treated fibres present slightly higher flexural modulus and impact strength than untreated fibres. This study is part of a LIFE project (MASTALMOND) aimed to create and test at preindustrial level new coloured masterbatches based on biodegradable polymers and containing in its formulation a high percentage of almond shell, a natural waste material, which firstly will permit to cover technical requirements of two traditional industrial sectors: toy and furniture, although the results achieved could be extended to other industrial sectors.

Keywords: additivation, almond shell, biodegradable, masterbatch, PLA, injection moulding

Procedia PDF Downloads 426
215 Modular Probe for Basic Monitoring of Water and Air Quality

Authors: Andrés Calvillo Téllez, Marianne Martínez Zanzarric, José Cruz Núñez Pérez

Abstract:

A modular system that performs basic monitoring of both water and air quality is presented. Monitoring is essential for environmental, aquaculture, and agricultural disciplines, where this type of instrumentation is necessary for data collection. The system uses low-cost components, which allows readings close to those with high-cost probes. The probe collects readings such as the coordinates of the geographical position, as well as the time it records the target parameters of the monitored. The modules or subsystems that make up the probe are the global positioning (GPS), which shows the altitude, latitude, and longitude data of the point where the reading will be recorded, a real-time clock stage, the date marking the time, the module SD memory continuously stores data, data acquisition system, central processing unit, and energy. The system acquires parameters to measure water quality, conductivity, pressure, and temperature, and for air, three types of ammonia, dioxide, and carbon monoxide gases were censored. The information obtained allowed us to identify the schedule of modification of the parameters and the identification of the ideal conditions for the growth of microorganisms in the water.

Keywords: calibration, conductivity, datalogger, monitoring, real time clock, water quality

Procedia PDF Downloads 104