Search results for: Francisco Cervantes Pérez
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 414

Search results for: Francisco Cervantes Pérez

204 Teacher Agency in Media Literacy: A Qualitative Study of Bolivian Teachers and Their Room to Manoeuvre

Authors: Daniela Lamaison Sepulveda

Abstract:

Critical media literacy teaches people to think analytically about the information they receive through the media. It is heavily influenced by Paulo Freire’s critical pedagogy and the necessity of becoming conscious of one’s reality in order to transform it. This qualitative research examines the case of Bolivia, which experienced dramatic political change after the first indigenous president, Evo Morales, was elected in 2006. In 2010, the government passed an education reform — the Avelino Siñani Elizardo Pérez (ASEP) —that draws heavily on decolonial thought and the Freirean notion of critical consciousness. The extent to which these theories were implemented in practice is evaluated in context of a media literacy project, run by an NGO, that trains secondary school teachers from public schools across Bolivia through yearly workshops ranging from producing media to identifying fake news. This context is examined against the backdrop of the highly contested general elections in October 2019. While there is plenty of literature that outlines the benefits of teaching media literacy in the classroom and different ways to apply it, little research has been done analysing implementation at an institutional level and how to best enable teachers who are motivated to teach the subject. Through semi-structured interviews, document analysis and naturalistic observations, this study aims to identify the struggles faced by teachers who are dedicated to teaching critical media literacy in their classrooms and how they navigate educational spaces while being subject to a demanding national curriculum that supposedly also seeks to promote critical thinking. The interplay between the aspirations of teachers and NGOs in contrast to the top-down discourse and policy of governmental institutions provides for a very enlightening case. By exploring these institutional, cultural, sociopolitical and economic barriers the teachers face, this research attempts to contribute to the debate in media literacy theories concerned with implementing the practice in schools.

Keywords: media literacy, critical pedagogy, teacher agency, misinformation, education reform, Bolivia

Procedia PDF Downloads 128
203 School Autonomy in the United Kingdom: A Correlational Study Applied to English Principals

Authors: Pablo Javier Ortega-Rodriguez, Francisco Jose Pozuelos-Estrada

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Recently, there has been a renewed interest in school autonomy in the United Kingdom and its impact on students' outcomes. English principals have a pivotal role in decision-making. The aim of this paper is to explore the correlation between the type of school (public or private) and the considerable responsibilities of English principals which participated in PISA 2015. The final sample consisted of 419 principals. Descriptive data (percentages and means) were generated for the variables related to professional autonomy. Pearson's chi-square test was used to determine if there is an association between the type of school and principals' responsibilities for relevant tasks. Statistical analysis was performed using SPSS software, version 22. Findings suggest a significant correlation between the type of school and principals' responsibility for firing teachers and formulating the school budget. This study confirms that the type of school is not associated with principals' responsibility for choosing which textbooks are used at school. The present study establishes a quantitative framework for defining four models of professional autonomy and some proposals to improve school autonomy in the United Kingdom.

Keywords: decision making, principals, professional autonomy, school autonomy

Procedia PDF Downloads 808
202 Influence of Cure Degree in GO and CNT-Epoxy Nanocomposites

Authors: Marina Borgert Moraes, Wesley Francisco, Filipe Vargas, Gilmar Patrocínio Thim

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In recent years, carbon nanotubes (CNT) and graphene oxide (GO), especially the functionalized ones, have been added to epoxy resin in order to increase the mechanical, electrical and thermal properties of nanocomposites. However, it's still unknown how the presence of these nanoparticles influences the curing process and the final mechanical properties as well. In this work, kinetic and mechanical properties of the nanocomposites were analyzed, where the kinetic process was followed by DSC and the mechanical properties by DMA. Initially, CNT was annealed at high temperature (1800 °C) under vacuum atmosphere, followed by a chemical treatment using acids and ethylenediamine. GO was synthesized through chemical route, washed clean, dried and ground to #200. The presence of functional groups on CNT and GO surface was confirmed by XPS spectra and FT-IR. Then, epoxy resin, nanoparticles and acetone were mixed by sonication in order to obtain the composites. DSC analyses were performed on samples with different curing cycles (1h 80°C + 2h 120°C; 3h 80°C + 2h 120°C; 5h 80°C) and samples with different times at constant temperature (120°C). Results showed that the kinetic process and the mechanical strength are very dependent on the presence of graphene and functionalized-CNT in the nanocomposites.

Keywords: carbon nanotube, epoxy resin, Graphene oxide, nanocomposite

Procedia PDF Downloads 319
201 Identifying the Factors that Influence Water-Use Efficiency in Agriculture: Case Study in a Spanish Semi-Arid Region

Authors: Laura Piedra-Muñoz, Ángeles Godoy-Durán, Emilio Galdeano-Gómez, Juan C. Pérez-Mesa

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The current agricultural system in some arid and semi-arid areas is not sustainable in the long term. In southeast Spain, groundwater is the main water source and is overexploited, while alternatives like desalination are still limited. The Water Plan for the Mediterranean Basins 2015-2020 indicates a global deficit of 73.42 hm3 and an overexploitation of the aquifers of 205.58hm3. In order to solve this serious problem, two major actions can be taken: increasing available water, and/or improving the efficiency of its use. This study focuses on the latter. The main aim of this study is to present the major factors related to water usage efficiency in farming. It focuses on Almería province, southeast Spain, one of the most arid areas of the country, and in particular on family farms as the main direct managers of water use in this zone. Many of these farms are among the most water efficient in Spanish agriculture, but this efficiency is not generalized throughout the sector. This work conducts a comprehensive assessment of water performance in this area, using on-farm water-use, structural, socio-economic and environmental information. Two statistical techniques are used: descriptive analysis and cluster analysis. Thus, two groups are identified: the least and the most efficient farms regarding water usage. By analyzing both the common characteristics within each group and the differences between the groups with a one-way ANOVA analysis, several conclusions can be reached. The main differences between the two clusters center on the extent to which innovation and new technologies are used in irrigation. The most water efficient farms are characterized by more educated farmers, a greater degree of innovation, new irrigation technology, specialized production and awareness of water issues and environmental sustainability. The research shows that better practices and policies can have a substantial impact on achieving a more sustainable and efficient use of water. The findings of this study can be extended to farms in similar arid and semi-arid areas and contribute to foster appropriate policies to improve the efficiency of water usage in the agricultural sector.

Keywords: cluster analysis, family farms, Spain, water-use efficiency

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200 The Effect of Leader Motivating Language on Work Performance and Job Satisfaction as Perceived by the Employees of Soro-Soro Ibaba Development Cooperative in Batangas City

Authors: Marlon P. Perez

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The study entitled “The Effect of Leader Motivating Language on Work Performance and Job Satisfaction as Perceived by the Employees of SoroSoro Ibaba Development Cooperative (SIDC)” primarily aims to evaluate the effect of leader’s use of motivating language in terms of the three types of speech acts namely, direction-giving language, empathetic language and meaning-making language with regard to the work performance and job satisfaction of the employees. The study made use of the descriptive method of this research that it followed certain processes in gathering the necessary and accurate information. Furthermore, survey questionnaires were used in order to congregate the respondents’ outlooks, opinions, and insight in the study. These survey questionnaires were distributed to one hundred fifty (150) employees from the five (5) outlets of SoroSoro Ibaba Development Cooperative (SIDC) in Batangas City who were chosen as the respondents of the study. However, only hundred twenty (120) out of one hundred fifty (150) or eighty (80) percent of the questionnaires were retrieved. Moreover, to accomplish the objectives of the study, different statistical treatments were used for the interpretation and analysis of the gathered data. These were the relative frequency, weighted mean, one-way analysis of variance and Pearson r. Based on those statistical treatments, researchers came up with the following results: first, most of the respondents were below 35 years old, males, college graduates and in regular status; second, direction-giving language, empathetic language, and meaning-making language affect the work performance and job satisfaction of the employees to a great extent; third, there was a non-significant difference with regards to the effect of leader motivating language on the work performance and job satisfaction of the employee; and, last, there was a significant relationship on the assessment of the effect of leader motivating language on work performance and job satisfaction when grouped according to respondents’ profile. Based on these results, various recommendations were conceptualized such as the designing of proposed activities like communication workshop and team-building to augment the communication between the leader and an employee. These activities could help for the development and attainment of an excellent communication within the different organizations and companies that are very important to any business success.

Keywords: leader motivating language, work performance, job satisfaction, employees

Procedia PDF Downloads 354
199 Heritage Preservation and Cultural Tourism; The 'Pueblos Mágicos' Program and Its Role in Preserving Traditional Architecture in Mexico

Authors: Claudia Rodríguez Espinosa, Erika Elizabeth Pérez Múzquiz

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The Pueblos Mágicos federal program tries to preserve the traditional environment of small towns (under 20,000 inhabitants), through economic investments, legislation, and legal aid. To access the program, it’s important to cover 8 requirements; one of them is the fourth, which considers ‘Promotion of symbolic and differentiated touristic attractions, such as architecture, emblematic buildings, festivities and traditions, artisan production, traditional cuisine, and touristic services that guarantee their commercialization along with assistantship and security services’. With this objective in mind, the Federal government of Mexico had developed local programs to protect emblematic public buildings in each of the 83 towns included in the Pueblos Mágicos program that involved federal and local administrations as well as local civil associations, like Adopte una Obra de Arte. In this paper, we present 3 different intervention cases: first the restoration project (now concluded) of the 16th century monastery of Santa María Magdalena in Cuitzeo, an enormous building which took 6 years to be completely restored. Second case, the public spaces intervention in Pátzcuaro, included the Plaza Grande or Vasco de Quiroga square, and the access to the arts and crafts house known as Casa de los once patios or eleven backyards house. The third case is the recovery project of the 16th century atrium of the Tzintzuntzan monastery that included the original olive trees brought by Franciscans monks to this town in the middle 1500’s. This paper tries to present successful preservation projects in 3 different scales: building, urban spaces and landscape; and in 3 different towns with the objective to preserve public architecture, public spaces and cultural traditions. Learn from foreign experiences, different ways to manage preservation projects focused on public architecture and public spaces.

Keywords: cultural tourism, heritage preservation, traditional architecture, public policies

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198 Comparison of Maternal and Perinatal Outcomes of Obstetric Population Diagnosed with Covid-19 in Reference to Influenza A/H1N1: A Systematic Review and Meta-Analysis

Authors: Maria Vargas Hernandez, Jose Rojas Suarez, Carmelo Dueñas Castell, Sandra Contreras, Camilo Bello, Diana Borre, Walter Anichiarico, Harold Vasquez, Eduard Perez, Jose Santacruz

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In the last two decades, there have been outbreaks of emerging infectious diseases, with an impact on both the general population and the obstetric population. These infections, which affect the general population, pose a high risk for adverse maternal and perinatal outcomes, taking into account that physiological and immunological changes that occur during pregnancy can increase their risk or severity. Among these, the pandemics of viral infections, Influenza A/H1N1 and SARS-CoV-2/COVID-19, stand out. In 2009, Influenza A/H1N1 infection (H1N1 2009pdm) affected approximately 3,110 obstetric patients, with data reported from 29 countries, including 1,625 (52.3%) cases that were hospitalized, 378 (23.3%) admissions to ICU and 130 (8%) deaths; and since the end of 2019, the Severe Acute Respiratory Syndrome - 2 (SARS-CoV-2) has been identified, causing the COVID-19 pandemic, with global mortality that is around 2-4% for the general population, and higher mortality in patients requiring admission to the intensive care unit. Its impact on the obstetric population is still unknown. Objectives: To evaluate the impact on maternal and perinatal outcomes of COVID-19 infection in reference to influenza A/H1N1 infection in the obstetric population. Methodology: Systematic review of the literature and meta-analysis. Results: Mortality from maternal infection with influenza A/H1N1 appears to be higher (8%) than mortality due to maternal infection with COVID-19 (3%). The rates of ICU admission, hospitalization, the requirement for invasive mechanical ventilation, and fetal death also appear to be higher in the maternal population with A/H1N1 infection, in reference to the maternal population with COVID-19 infection. Within perinatal outcomes, the admission to the neonatal ICU appears to be higher in the infants born to mothers with COVID-19 infection (28% vs. 15% for COVID-19 and A/H1N1, respectively). Conclusion: A/H1N1 infection in the obstetric population seems to be associated with a higher proportion of adverse outcomes in relation to COVID-19 infection. The actual impact of maternal influenza A/H1N1 infection on perinatal outcomes is unknown. More COVID-19 studies are needed to understand the impact of maternal infection on perinatal outcomes in this population.

Keywords: A/H1N1, COVID-19, maternal outcomes, perinatal outcomes

Procedia PDF Downloads 226
197 Family Health in Families with Children with Autism

Authors: Teresa Isabel Lozano Pérez, Sandra Soca Lozano

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In Cuba, the childcare is one of the programs prioritized by the Ministry of Public Health and the birth of a child becomes a desired and rewarding event for the family, which is prepared for the reception of a healthy child. When this does not happen and after the first months of the child's birth begin to appear developmental deviations that indicate the presence of a disorder, the event becomes a live event potentially negative and generates disruptions in the family health. A quantitative, descriptive, and cross-sectional research methodology was conducted to describe the impact on family health of diagnosis of autism in a sample of 25 families of children diagnosed with infantile autism at the University Pediatric Hospital Juan Manuel Marquez Havana, Cuba; in the period between January 2014 and May 2015. The sample was non probabilistic and intentional from the inclusion criteria selected. As instruments, we used a survey to identify the structure of the family, life events inventory and an instrument to assess the relative impact, adaptive resources of family and social support perceived (IRFA) to identify the diagnosis of autism as life event. The main results indicated that the majority of families studied were nuclear, small and medium and in the formation stage. All households surveyed identified the diagnosis of autism in a child as an event of great importance and negative significance for the family, taking in most of the families studied a high impact on the four areas of family health and impact enhancer of involvement in family health. All the studied families do not have sufficient adaptive resources to face this situation, sensing that they received social support frequently, mainly in information and emotional areas. We conclude that the diagnosis of autism one of the members of the families studied is valued as a life event highly significant with unfavorably way causing an enhancer impact of involvement in family health especially in the areas ‘health’ and ‘socio-psychological’. Among the social support networks health institutions, partners and friends are highlighted. We recommend developing intervention strategies in families of these children to support them in the process of adapting the diagnosis.

Keywords: family, family health, infantile autism, life event

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196 Arginase Enzyme Activity in Human Serum as a Marker of Cognitive Function: The Role of Inositol in Combination with Arginine Silicate

Authors: Katie Emerson, Sara Perez-Ojalvo, Jim Komorowski, Danielle Greenberg

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The purpose of this study was to evaluate arginase activity levels in response to combinations of an inositol-stabilized arginine silicate (ASI; Nitrosigine®), L-arginine, and Inositol. Arginine acts as a vasodilator that promotes increased blood flow resulting in enhanced delivery of oxygen and nutrients to the brain and other tissues. ASI alone has been shown to improve performance on cognitive tasks. Arginase, found in human serum, catalyzes the conversion of arginine to ornithine and urea, completing the last step in the urea cycle. Decreasing arginase levels maintains arginine and results in increased nitric oxide production. This study aimed to determine the most effective combination of ASI, L-arginine and inositol for minimizing arginase levels and therefore maximize ASI’s effect on cognition. Serum was taken from untreated healthy donors by separation from clotted factors. Arginase activity of serum in the presence or absence of test products was determined (QuantiChrom™, DARG-100, Bioassay Systems, Hayward CA). The remaining ultra-filtrated serum units were harvested and used as the source for the arginase enzyme. ASI alone or combined with varied levels of Inositol were tested as follows: ASI + inositol at 0.25 g, 0.5 g, 0.75 g, or 1.00 g. L-arginine was also tested as a positive control. All tests elicited changes in arginase activity demonstrating the efficacy of the method used. Adding L-arginine to serum from untreated subjects, with or without inositol only had a mild effect. Adding inositol at all levels reduced arginase activity. Adding 0.5 g to the standardized amount of ASI led to the lowest amount of arginase activity as compared to the 0.25g 0.75g or 1.00g doses of inositol or to L-arginine alone. The outcome of this study demonstrates an interaction of the pairing of inositol with ASI on the activity of the enzyme arginase. We found that neither the maximum nor minimum amount of inositol tested in this study led to maximal arginase inhibition. Since the inhibition of arginase activity is desirable for product formulations looking to maintain arginine levels, the most effective amount of inositol was deemed preferred. Subsequent studies suggest this moderate level of inositol in combination with ASI leads to cognitive improvements including reaction time, executive function, and concentration.

Keywords: arginine, inositol, arginase, cognitive benefits

Procedia PDF Downloads 113
195 An Overview of Suicidality in American Indians and Alaska Natives

Authors: Christopher S. Perez, Kendal C. Boyd

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global suicide rates have decreased in recent decades, rates in the United States have increased by 35.2 percent since 1999.American Indians and Alaska Natives (AI/AN) have the highest rates of suicide in the U.S., with approximately 22 suicides per 100,000 people as of 2019. AI/AN have experienced significant historical trauma resulting in disproportionate rates of substance abuse and mental disorders. This literature review aimed to identify the demographic and clinical risk and protective factors for American Indians and Alaska Natives and provide an overview of suicidality in this population. The literature reflected varying definitions of suicidality depending on region, with some AI/AN tribesconceptualizing suicide through a spiritual framework, while others defined suicide in the biomedical sense. Furthermore, AI/AN adults and adolescents experienced higher rates of suicidal ideation when compared to other racial groups. Religious preference, sexual orientation, prior suicidal behavior, psychiatric admission, history of abuse, substance abuse, family history of mental illness, family history of substance abuse, family history of suicidal behaviors, domestic violence, and trauma were discussed as factors related to suicidality. Recommendations included increasing access to and utilization of mental health and medical services, culturally adapting suicide prevention programs to AI/AN communities, increasing support for LGBTQ+ AI/AN, providing opportunities that reinforce ethnic identity, and post-hospitalization follow-up care. The following databases were utilized to obtain peer-reviewed articles for this literature review: Complementary Index, Academic Search Premier, Science Direct, PsycInfo, Social Sciences Citation Index, PsycArticles, PubMed, EbscoHost, and PsycBooks. Articles that examined Native populations outside of the United States did not cite a primary source and/or were published before 1990 were excluded.

Keywords: alaska native, american indian, protective factors, risk factors, suicidality, suicide

Procedia PDF Downloads 101
194 A Xenon Mass Gauging through Heat Transfer Modeling for Electric Propulsion Thrusters

Authors: A. Soria-Salinas, M.-P. Zorzano, J. Martín-Torres, J. Sánchez-García-Casarrubios, J.-L. Pérez-Díaz, A. Vakkada-Ramachandran

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The current state-of-the-art methods of mass gauging of Electric Propulsion (EP) propellants in microgravity conditions rely on external measurements that are taken at the surface of the tank. The tanks are operated under a constant thermal duty cycle to store the propellant within a pre-defined temperature and pressure range. We demonstrate using computational fluid dynamics (CFD) simulations that the heat-transfer within the pressurized propellant generates temperature and density anisotropies. This challenges the standard mass gauging methods that rely on the use of time changing skin-temperatures and pressures. We observe that the domes of the tanks are prone to be overheated, and that a long time after the heaters of the thermal cycle are switched off, the system reaches a quasi-equilibrium state with a more uniform density. We propose a new gauging method, which we call the Improved PVT method, based on universal physics and thermodynamics principles, existing TRL-9 technology and telemetry data. This method only uses as inputs the temperature and pressure readings of sensors externally attached to the tank. These sensors can operate during the nominal thermal duty cycle. The improved PVT method shows little sensitivity to the pressure sensor drifts which are critical towards the end-of-life of the missions, as well as little sensitivity to systematic temperature errors. The retrieval method has been validated experimentally with CO2 in gas and fluid state in a chamber that operates up to 82 bar within a nominal thermal cycle of 38 °C to 42 °C. The mass gauging error is shown to be lower than 1% the mass at the beginning of life, assuming an initial tank load at 100 bar. In particular, for a pressure of about 70 bar, just below the critical pressure of CO2, the error of the mass gauging in gas phase goes down to 0.1% and for 77 bar, just above the critical point, the error of the mass gauging of the liquid phase is 0.6% of initial tank load. This gauging method improves by a factor of 8 the accuracy of the standard PVT retrievals using look-up tables with tabulated data from the National Institute of Standards and Technology.

Keywords: electric propulsion, mass gauging, propellant, PVT, xenon

Procedia PDF Downloads 346
193 Understanding Evolutionary Algorithms through Interactive Graphical Applications

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

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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
192 Biological Regulation of Endogenous Enzymatic Activity of Rainbow Trout (Oncorhynchus Mykiss) with Protease Inhibitors Chickpea in Model Systems

Authors: Delgado-Meza M., Minor-Pérez H.

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Protease is the generic name of enzymes that hydrolyze proteins. These are classified in the subgroup EC3.4.11-99X of the classification enzymes. In food technology the proteolysis is used to modify functional and nutritional properties of food, and in some cases this proteolysis may cause food spoilage. In general, seafood and rainbow trout have accelerated decomposition process once it has done its capture, due to various factors such as the endogenous enzymatic activity that can result in loss of structure, shape and firmness, besides the release of amino acid precursors of biogenic amines. Some studies suggest the use of protease inhibitors from legume as biological regulators of proteolytic activity. The enzyme inhibitors are any substance that reduces the rate of a reaction catalyzed by an enzyme. The objective of this study was to evaluate the reduction of the proteolytic activity of enzymes in extracts of rainbow trout with protease inhibitors obtained from chickpea flour. Different proportions of rainbow trout enzyme extract (75%, 50% and 25%) and extract chickpea enzyme inhibitors were evaluated. Chickpea inhibitors were obtained by mixing 5 g of flour in 30 mL of pH 7.0 phosphate buffer. The sample was centrifuged at 8000 rpm for 10 min. The supernatant was stored at -15°C. Likewise, 20 g of rainbow trout were ground in 20 mL of phosphate buffer solution at pH 7.0 and the mixture was centrifuged at 5000 rpm for 20 min. The supernatant was used for the study. In each treatment was determined the specific enzymatic activity with the technique of Kunitz, using hemoglobin as substrate for the enzymes acid fraction and casein for basic enzymes. Also biuret protein was quantified for each treatment. The results showed for fraction of basic enzymes in the treatments evaluated, that were inhibition of endogenous enzymatic activity. Inhibition values compared to control were 51.05%, 56.59% and 59.29% when the proportions of endogenous enzymes extract rainbow trout were 75%, 50% and 25% and the remaining volume used was extract with inhibitors. Treatments with acid enzymes showed no reduction in enzyme activity. In conclusion chickpea flour reduced the endogenous enzymatic activity of rainbow trout, which may favor its application to increase the half-life of this food. The authors acknowledge the funding provided by the CONACYT for the project 131998.

Keywords: rainbouw trout, enzyme inhibitors, proteolysis, enzyme activity

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191 Mortar Positioning Effects on Uniaxial Compression Behavior in Hollow Concrete Block Masonry

Authors: José Álvarez Pérez, Ramón García Cedeño, Gerardo Fajardo-San Miguel, Jorge H. Chávez Gómez, Franco A. Carpio Santamaría, Milena Mesa Lavista

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The uniaxial compressive strength and modulus of elasticity in hollow concrete block masonry (HCBM) represent key mechanical properties for structural design considerations. These properties are obtained through experimental tests conducted on prisms or wallettes and depend on various factors, with the HCB contributing significantly to overall strength. One influential factor in the compressive behaviour of masonry is the thickness and method of mortar placement. Mexican regulations stipulate mortar placement over the entire net area (full-shell) for strength computation based on the gross area. However, in professional practice, there's a growing trend to place mortar solely on the lateral faces. Conversely, the United States of America standard dictates mortar placement and computation over the net area of HCB. The Canadian standard specifies mortar placement solely on the lateral face (Face-Shell-Bedding), where computation necessitates the use of the effective load area, corresponding to the mortar's placement area. This research aims to evaluate the influence of different mortar placement methods on the axial compression behaviour of HCBM. To achieve this, an experimental campaign was conducted, including: (1) 10 HCB specimens with mortar on the entire net area, (2) 10 HCB specimens with mortar placed on the lateral faces, (3) 10 prisms of 2-course HCB under axial compression with mortar in full-shell, (4) 10 prisms of 2-course HCB under axial compression with mortar in face-shell-bedding, (5) 10 prisms of 3-course HCB under axial compression with mortar in full-shell, (6) 10 prisms of 3-course HCB under axial compression with mortar in face-shell-bedding, (7) 10 prisms of 4-course HCB under axial compression with mortar in full-shell, and, (8) 10 prisms of 4-course HCB under axial compression with mortar in face-shell-bedding. A combination of sulphur and fly ash in a 2:1 ratio was used for the capping material, meeting the average compressive strength requirement of over 35 MPa as per NMX-C-036 standards. Additionally, a mortar with a strength of over 17 MPa was utilized for the prisms. The results indicate that prisms with mortar placed over the full-shell exhibit higher strength compared to those with mortar over the face-shell-bedding. However, the elastic modulus was lower for prisms with mortar placement over the full-shell compared to face-shell bedding.

Keywords: masonry, hollow concrete blocks, mortar placement, prisms tests

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190 Self-Efficacy and Self-Worth of Elderly in Geriatric Institutions

Authors: Melasurej C. Francisco, Sophia D. Rusit

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Old age is a record of one’s own life; this is the crucial phase for most. However, there are individuals who believe that old people retain self-efficacy and self-worth throughout their existence. Geriatric institutions focus on the health of elderly, in which they have been supported with medicines and therapies by clinician thus, indicating that these may suffice physical, emotional, and mental health of the elderly. This study focuses on (1) Describing the level or degree of self-efficacy; (2) Recognizing the extent of self-worth; (3) Determining the significant relationship between self-efficacy and self-worth. It is a mixed method design. A combination of correlational research and in-depth interview. Purposive sampling technique was used to select participants, considering that this assay focused on elderly in geriatric institutions, it follows that respondents and participants are at least sixty years of age and must be living inside the institution. 121 senior citizens took part in this study. Scores from both General Self-Efficacy Scale (GSE) and Rosenberg Self-Esteem Scale (RSES) showed varying levels of self-efficacy and self-worth. SE had μ=28.099, σ=6.6262, σ²=43.9067 while; SW had μ=14.9669, σ=5.3789, σ²28.9322 which denotes that rₒbₜ (121)=0.3164 is higher than rcᵢₜ which is 0.150. Although this exhibits the positive moderate correlation between SE and SW, the relationship between variables is weak. Likewise, the pᵥₐₗᵤₑ (pᵥₐₗᵤₑ=0.000406) is lower than the significance level alpha=0.01, thus, rejecting the null hypothesis, and accepting the alternative hypothesis.

Keywords: elderly, geriatric, self-efficacy, self-worth

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189 Positive Interactions among Plants in Pinegroves over Quarzitic Sands

Authors: Enrique González Pendás, Vidal Pérez Hernández, Jorge Ferro Díaz, Nelson Careaga Pendás

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The investigation is carried out on the Protected Area of San Ubaldo, toward the interior of an open pinegrove with palm trees in a dry plainness of quar zitic sands, belonging to the Floristic Managed Reservation San Ubaldo-Sabanalamar, Guane, Pinar del Río, Cuba. This area is characterized by drastic seasonal variations, high temperatures and water evaporation, strong solar radiation, with sandy soils of almost pure quartz, which are very acid and poor in nutrients. The objective of the present work is to determine evidence of facilitation and its relationship with the structure and composition of plant communities in these peculiar ecosystems. For this study six lineal parallel transepts of 100 m are traced, in those, a general recording of the flora is carried out. To establish which plants act as nurses, is taken into account a height over 1 meter, canopy over 1.5 meter and the occurrence of several species under it. Covering was recorded using the line intercept method; the medium values of species richness for the taxa under nurses is compared with those that are located in open spaces among them. Then, it is determined which plants are better recruiter of other species (better nurses). An experiment is made to measure and compare some parameters in pine seedlings under the canopy of the Byrsonima crassifolia (L.) Kunth. and in open spaces, also the number of individuals is counted by species to calculate the frequency and total abundance in the study area. As a result, it is offered an up-to-date floristic list, a phylogenetic tree of the plant community showing a high phylodiversity, it is proven that the medium values of species richness and abundance of species under the nurses, is significantly superior to those occurring in open spaces. Furthermore, by means of phylogenetic trees it is shown that the species which cohabit under the nurses are not phylogenetically related. The former results are cited evidences of facilitation among plants, as well as it is one more time shown the importance of the nurse effect in preserving plant diversity on extreme environments.

Keywords: facilitation, nurse plants, positive interactions, quarzitic sands

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188 A Statistical Approach to Air Pollution in Mexico City and It's Impacts on Well-Being

Authors: Ana B. Carrera-Aguilar , Rodrigo T. Sepulveda-Hirose, Diego A. Bernal-Gurrusquieta, Francisco A. Ramirez Casas

Abstract:

In recent years, Mexico City has presented high levels of atmospheric pollution; the city is also an example of inequality and poverty that impact metropolitan areas around the world. This combination of social and economic exclusion, coupled with high levels of pollution evidence the loss of well-being among the population. The effect of air pollution on quality of life is an area of study that has been overlooked. The purpose of this study is to find relations between air quality and quality of life in Mexico City through statistical analysis of a regression model and principal component analysis of several atmospheric contaminants (CO, NO₂, ozone, particulate matter, SO₂) and well-being indexes (HDI, poverty, inequality, life expectancy and health care index). The data correspond to official information (INEGI, SEDEMA, and CEPAL) for 2000-2018. Preliminary results show that the Human Development Index (HDI) is affected by the impacts of pollution, and its indicators are reduced in the presence of contaminants. It is necessary to promote a strong interest in this issue in Mexico City. Otherwise, the problem will not only remain but will worsen affecting those who have less and the population well-being in a generalized way.

Keywords: air quality, Mexico City, quality of life, statistics

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187 Deproteination and Demineralization of Shrimp Waste Using Lactic Acid Bacteria for the Production of Crude Chitin and Chitosan

Authors: Farramae Francisco, Rhoda Mae Simora, Sharon Nunal

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Deproteination and demineralization efficiencies of shrimp waste using two Lactobacillus species treated with different carbohydrate sources for chitin production, its chemical conversion to chitosan and the quality of chitin and chitosan produced were determined. Using 5% glucose and 5% cassava starch as carbohydrate sources, pH slightly increased from the initial pH of 6.0 to 6.8 and 7.2, respectively after 24 h and maintained their pH at 6.7 to 7.3 throughout the treatment period. Demineralization (%) in 5 % glucose and 5 % cassava was highest during the first day of treatment which was 82% and 83%, respectively. Deproteination (%) was highest in 5% cassava starch on the 3rd day of treatment at 84.4%. The obtained chitin from 5% cassava and 5% glucose had a residual ash and protein below 1% and solubility of 59% and 44.3%, respectively. Chitosan produced from 5% cassava and 5% glucose had protein content below 0.05%; residual ash was 1.1% and 0.8%, respectively. Chitosan solubility and degree of deacetylation were 56% and 33% in 5% glucose and 48% and 29% in 5% cassava, respectively. The advantage this alternative technology offers over that of chemical extraction is large reduction in chemicals needed thus less effluent production and generation of a protein-rich liquor, although the demineralization process should be improved to achieve greater degree of deacetylation.

Keywords: alternative carbon source, bioprocessing, lactic acid bacteria, waste utilization

Procedia PDF Downloads 487
186 Microstructural Characterization of Bitumen/Montmorillonite/Isocyanate Composites by Atomic Force Microscopy

Authors: Francisco J. Ortega, Claudia Roman, Moisés García-Morales, Francisco J. Navarro

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Asphaltic bitumen has been largely used in both industrial and civil engineering, mostly in pavement construction and roofing membrane manufacture. However, bitumen as such is greatly susceptible to temperature variations, and dramatically changes its in-service behavior from a viscoelastic liquid, at medium-high temperatures, to a brittle solid at low temperatures. Bitumen modification prevents these problems and imparts improved performance. Isocyanates like polymeric MDI (mixture of 4,4′-diphenylmethane di-isocyanate, 2,4’ and 2,2’ isomers, and higher homologues) have shown to remarkably enhance bitumen properties at the highest in-service temperatures expected. This comes from the reaction between the –NCO pendant groups of the oligomer and the most polar groups of asphaltenes and resins in bitumen. In addition, oxygen diffusion and/or UV radiation may provoke bitumen hardening and ageing. With the purpose of minimizing these effects, nano-layered-silicates (nanoclays) are increasingly being added to bitumen formulations. Montmorillonites, a type of naturally occurring mineral, may produce a nanometer scale dispersion which improves bitumen thermal, mechanical and barrier properties. In order to increase their lipophilicity, these nanoclays are normally treated so that organic cations substitute the inorganic cations located in their intergallery spacing. In the present work, the combined effect of polymeric MDI and the commercial montmorillonite Cloisite® 20A was evaluated. A selected bitumen with penetration within the range 160/220 was modified with 10 wt.% Cloisite® 20A and 2 wt.% polymeric MDI, and the resulting ternary composites were characterized by linear rheology, X-ray diffraction (XRD) and Atomic Force Microscopy (AFM). The rheological tests evidenced a notable solid-like behavior at the highest temperatures studied when bitumen was just loaded with 10 wt.% Cloisite® 20A and high-shear blended for 20 minutes. However, if polymeric MDI was involved, the sequence of addition exerted a decisive control on the linear rheology of the final ternary composites. Hence, in bitumen/Cloisite® 20A/polymeric MDI formulations, the previous solid-like behavior disappeared. By contrast, an inversion in the order of addition (bitumen/polymeric MDI/ Cloisite® 20A) enhanced further the solid-like behavior imparted by the nanoclay. In order to gain a better understanding of the factors that govern the linear rheology of these ternary composites, a morphological and microstructural characterization based on XRD and AFM was conducted. XRD demonstrated the existence of clay stacks intercalated by bitumen molecules to some degree. However, the XRD technique cannot provide detailed information on the extent of nanoclay delamination, unless the entire fraction has effectively been fully delaminated (situation in which no peak is observed). Furthermore, XRD was unable to provide precise knowledge neither about the spatial distribution of the intercalated/exfoliated platelets nor about the presence of other structures at larger length scales. In contrast, AFM proved its power at providing conclusive information on the morphology of the composites at the nanometer scale and at revealing the structural modification that yielded the rheological properties observed. It was concluded that high-shear blending brought about a nanoclay-reinforced network. As for the bitumen/Cloisite® 20A/polymeric MDI formulations, the solid-like behavior was destroyed as a result of the agglomeration of the nanoclay platelets promoted by chemical reactions.

Keywords: Atomic Force Microscopy, bitumen, composite, isocyanate, montmorillonite.

Procedia PDF Downloads 261
185 Synthetic Aperture Radar Remote Sensing Classification Using the Bag of Visual Words Model to Land Cover Studies

Authors: Reza Mohammadi, Mahmod R. Sahebi, Mehrnoosh Omati, Milad Vahidi

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Classification of high resolution polarimetric Synthetic Aperture Radar (PolSAR) images plays an important role in land cover and land use management. Recently, classification algorithms based on Bag of Visual Words (BOVW) model have attracted significant interest among scholars and researchers in and out of the field of remote sensing. In this paper, BOVW model with pixel based low-level features has been implemented to classify a subset of San Francisco bay PolSAR image, acquired by RADARSAR 2 in C-band. We have used segment-based decision-making strategy and compared the result with the result of traditional Support Vector Machine (SVM) classifier. 90.95% overall accuracy of the classification with the proposed algorithm has shown that the proposed algorithm is comparable with the state-of-the-art methods. In addition to increase in the classification accuracy, the proposed method has decreased undesirable speckle effect of SAR images.

Keywords: Bag of Visual Words (BOVW), classification, feature extraction, land cover management, Polarimetric Synthetic Aperture Radar (PolSAR)

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184 Psychological Capital and Work Engagement as Predictors of Employee Performance in a Technology Industry During COVID-19 Pandemic: Basis for Performance Management

Authors: Marion Francisco

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The study sought to investigate the psychological capital and work engagement of employees as predictors of employee performance in the technology industry in Makati City. It made used of a descriptive correlational method of research and utilized standardized tests, such as Psychological Capital Scale, Utrech Work Engagement Scale, and Employee Performance Scale. A convenience sampling technique was used to gather data samples from 100 populations with the help of Roscoe concept approach. The study revealed that both psychological capital and work engagement have a significant relationship with employee performance. Psychological capital and work engagement can predict employee performance of the respondents. With the results given, the study suggests: (1) to focus on maintaining a high level of psychological capital and work engagement, on achieving a very high level of psychological capital and work engagement, and on improving the low level of psychological capital or work engagement mostly during this COVID-19 pandemic using the proposed employee performance management plan and (2) to create a proposed employee performance management plan as necessary to tailor fit on employees needs to enhance their performance that will help meet company and client’s needs.

Keywords: employee performance, performance management, psychological capital, technology industry, work engagement

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183 Study Case of Spacecraft Instruments in Structural Modelling with Nastran-Patran

Authors: Francisco Borja de Lara, Ali Ravanbakhsh, Robert F. Wimmer-Schweingruber, Lars Seimetz, Fermín Navarro

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The intense structural loads during the launch of a spacecraft represent a challenge for the space structure designers because enough resistance has to be achieved while maintaining at the same time the mass and volume within the allowable margins of the mission requirements and inside the limits of the budget project. In this conference, we present the structural analysis of the Lunar Lander Neutron Dosimetry (LND) experiment on the Chang'E4 mission, the first probe to land on the moon’s far side included in the Chinese’ Moon Exploration Program by the Chinese National Space Administration. To this target, the software Nastran/Patran has been used: a structural model in Patran and a structural analysis through Nastran have been realized. Next, the results obtained are used both for the optimization process of the spacecraft structure, and as input parameters for the model structural test campaign. In this way, the feasibility of the lunar instrument structure is demonstrated in terms of the modal modes, stresses, and random vibration and a better understanding of the structural tests design is provided by our results.

Keywords: Chang’E4, Chinese national space administration, lunar lander neutron dosimetry, nastran-patran, structural analysis

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182 A Comparative Study of Natural Language Processing Models for Detecting Obfuscated Text

Authors: Rubén Valcarce-Álvarez, Francisco Jáñez-Martino, Rocío Alaiz-Rodríguez

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Cybersecurity challenges, including scams, drug sales, the distribution of child sexual abuse material, fake news, and hate speech on both the surface and deep web, have significantly increased over the past decade. Users who post such content often employ strategies to evade detection by automated filters. Among these tactics, text obfuscation plays an essential role in deceiving detection systems. This approach involves modifying words to make them more difficult for automated systems to interpret while remaining sufficiently readable for human users. In this work, we aim at spotting obfuscated words and the employed techniques, such as leetspeak, word inversion, punctuation changes, and mixed techniques. We benchmark Named Entity Recognition (NER) using models from the BERT family as well as two large language models (LLMs), Llama and Mistral, on XX_NER_WordCamouflage dataset. Our experiments evaluate these models by comparing their precision, recall, F1 scores, and accuracy, both overall and for each individual class.

Keywords: natural language processing (NLP), text obfuscation, named entity recognition (NER), deep learning

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181 Optimizing Resource Allocation and Indoor Location Using Bluetooth Low Energy

Authors: Néstor Álvarez-Díaz, Pino Caballero-Gil, Héctor Reboso-Morales, Francisco Martín-Fernández

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The recent tendency of "Internet of Things" (IoT) has developed in the last years, causing the emergence of innovative communication methods among multiple devices. The appearance of Bluetooth Low Energy (BLE) has allowed a push to IoT in relation to smartphones. In this moment, a set of new applications related to several topics like entertainment and advertisement has begun to be developed but not much has been done till now to take advantage of the potential that these technologies can offer on many business areas and in everyday tasks. In the present work, the application of BLE technology and smartphones is proposed on some business areas related to the optimization of resource allocation in huge facilities like airports. An indoor location system has been developed through triangulation methods with the use of BLE beacons. The described system can be used to locate all employees inside the building in such a way that any task can be automatically assigned to a group of employees. It should be noted that this system cannot only be used to link needs with employees according to distances, but it also takes into account other factors like occupation level or category. In addition, it has been endowed with a security system to manage business and personnel sensitive data. The efficiency of communications is another essential characteristic that has been taken into account in this work.

Keywords: bluetooth low energy, indoor location, resource assignment, smartphones

Procedia PDF Downloads 395
180 Self-Care and Risk Behaviors in Primary Caregiver of Cancer Patients

Authors: Ivonne N. Pérez-Sánchez. María L. Rascón- Gasca, Angélica Riveros-Rosas, Rebeca Robles García

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Introduction: Primary caregivers of cancer patients have health problems related to their lack of time, stress, and fiscal strain. Their health problems could affect their patients’ health and also increase the expenses in public health. Aim: To describe self-care and risk behaviors in a sample of Mexican primary caregiver and the relation of these behaviors with emotional distress (caregiver burden, anxiety and depression symptoms), coping and sociodemographic variables. Method: Participated in this study 173 caregivers of a third level reference medical facility (age: M=49.4, SD=13.5) females 78%, males 22%, 57.5% were caregivers of patients with terminal cancer (CPTC), and 40.5% were caregivers of patients on oncology treatment (CPOT). Results: The 75.7% of caregivers reported to have had health problem in last six months as well as several symptoms which were related to emotional distress, these symptoms were more frequently between CPTC and female caregivers. A half (47.3%) of sample reported have had difficulties in caring their health; these difficulties were related to emotional distress and lower coping, more affected caregivers were who attend male patients and CPTC. The 76.8% of caregivers had health problems in last six months, but 26.5% of them waited to search medical care until they were very sick, and 11% didn't do it. Also, more than a half of sample (56.1%) admitted to have risk behaviors as drink alcohol, smoke or overeating for feeling well, these caregivers showed high emotional distress and lower coping. About caregivers healthy behaviors, 80% of them had a hobby; 27.2% do exercise usually and between 12% to 60% did medical checkups (glucose tests, blood pressure and cholesterol tests, eye exams and watched their weight), these caregivers had lower emotional distress and high coping, some variables related health behaviors were: care only one patient or a female patient and be a CPOT, social support, high educational level and experience as a caregiver in past. The half of caregivers were worrying to develop cancer in the future; this idea was 2.5 times more frequent in caregiver with problems to care their health. Conclusions: The results showed a big proportion of caregivers with medical problems. High emotional distress and low coping were related to physical symptoms, risk behaviors, and low self-care; poor self-care was frequently even in caregiver who have chronic illness.

Keywords: cancer, primary caregiver, risk behaviors, self-care

Procedia PDF Downloads 405
179 Maintenance of Non-Crop Plants Reduces Insect Pest Population in Tropical Chili Pepper Agroecosystems

Authors: Madelaine Venzon, Dany S. S. L. Amaral, André L. Perez, Natália S. Diaz, Juliana A. Martinez Chiguachi, Maira C. M. Fonseca, James D. Harwood, Angelo Pallini

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Integrating strategies of sustainable crop production and promoting the provisioning of ecological services on farms and within rural landscapes is a challenge for today’s agriculture. Habitat management, through increasing vegetational diversity, enhances heterogeneity in agroecosystems and has the potential to improve the recruitment of natural enemies of pests, which promotes biological control services. In tropical agroecosystems, however, there is a paucity of information pertaining to the resources provided by associated plants and their interactions with natural enemies. The maintenance of non-crop plants integrated into and/or surrounding crop fields provides the farmer with a low-investment option to enhance biological control. We carried out field experiments in chili pepper agroecosystems with small stakeholders located in the Zona da Mata, State of Minas Gerais, Brazil, from 2011 to 2015 where we assessed: (a) whether non-crop plants within and around chili pepper fields affect the diversity and abundance of aphidophagous species; (b) whether there are direct interactions between non-crop plants and aphidophagous arthropods; and (c) the importance of non-crop plant resources for survival of Coccinellidae and Chrysopidae species. Aphidophagous arthropods were dominated by Coccinellidae, Neuroptera, Syrphidae, Anthocoridae and Araneae. These natural enemies were readily observed preying on aphids, feeding on flowers or extrafloral nectaries and using plant structures for oviposition and/or protection. Aphid populations were lower on chili pepper fields associated with non-crop plants that on chili pepper monocultures. Survival of larvae and adults of different species of Coccinellidae and Chrysopidae on non-crop resources varied according to the plant species. This research provides evidence that non-crop plants in chili pepper agroecosystems can affect aphid abundance and their natural enemy abundance and survival. It is also highlighting the need for further research to fully characterize the structure and function of plant resources in these and other tropical agroecosystems. Financial support: CNPq, FAPEMIG and CAPES (Brazil).

Keywords: Conservation biological control, aphididae, Coccinellidae, Chrysopidae, plant diversification

Procedia PDF Downloads 291
178 Magnetic Lines of Force and Diamagnetism

Authors: Angel Pérez Sánchez

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Magnet attraction or repulsion is not a product of a strange force from afar but comes from anchored lines of force inside the magnet as if it were reinforced concrete since you can move a small block by taking the steel rods that protrude from its interior. This approach serves as a basis for studying the behavior of diamagnetic materials. The significance of this study is to unify all diamagnetic phenomena: Movement of grapes, cooper approaching a magnet, Magnet levitation, etc., with a single explanation for all these phenomena. The method followed has consisted of observation of hundreds of diamagnetism experiments (in copper, aluminum, grapes, tomatoes, and bismuth), including the creation of own and new experiments and application of logical deduction product of these observations. Approaching a magnet to a hanging grape, Diamagnetism seems to consist not only of a slight repulsion but also of a slight attraction at a small distance. Replacing the grapes with a copper sphere, it behaves like the grape, pushing and pulling a nearby magnet. Diamagnetism could be redefined in the following way: There are materials that don't magnetize their internal structure when approaching a magnet, as ferromagnetic materials do. But they do allow magnetic lines of force to run through its interior, enhancing them without creating their own lines of force. Magnet levitates on superconducting ceramics because magnet gives lines near poles a force superior to what a superconductor can enhance these lines. Little further from the magnet, enhancing of lines by the superconductor is greater than the strength provided by the magnet due to the distance from the magnet's pole. It is this point that defines the magnet's levitation band. The anchoring effect of lines is what ultimately keeps the magnet and superconductor at a certain distance. The magnet seeks to levitate the area in which magnetic lines are stronger near de magnet's poles. Pouring ferrofluid into a magnet, lines of force are observed coming out of the poles. On other occasions, diamagnetic materials simply enhance the lines they receive without moving their position since their own weight is greater than the strength of the enhanced lines. (This is the case with grapes and copper). Magnet and diamagnetic materials look for a place where the lines of force are most enhanced, and this is at a small distance. Once the ideal distance is established, they tend to keep it by pushing or pulling on each other. At a certain distance from the magnet: the power exerted by diamagnetic materials is greater than the force of lines in the vicinity of the magnet's poles. All Diamagnetism phenomena: copper, aluminum, grapes, tomatoes, bismuth levitation, and magnet levitation on superconducting ceramics can now be explained with the support of magnetic lines of force.

Keywords: diamagnetism, magnetic levitation, magnetic lines of force, enhancing magnetic lines

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177 Development of Biotechnological Emulsion Based on Bullfrog (Rana catesbeiana Shaw) Oil: A Preliminary Study

Authors: Lourena M. Veríssimo, Lucas A. Machado, Renata Rutckeviski, Francisco H. Xavier Júnior, Éverton N. Alencar, Andreza R. V. Morais, Teresa R. F. Dantas, Christian M. Oliveira, Arnóbio A. Silva Júnior, Eryvaldo S. T. Egito

Abstract:

This study aimed to obtain emulsion systems based on bullfrog oil (BO). The BO was extracted at 80ºC and analyzed by Gas Chromatography-Mass Spectrometry (GC/MS). The critical Hydrophilic-Lipophilic Balance (HLBc) Assay of the BO was performed through BO, Tween® 20, Span® 80 and deionized water mixtures using an Ultra-Turrax® and determined using dynamic light scattering, pH, electrical conductivity and creaming rate. Then, a pseudoternary phase diagram (PPD) was constructed by water titration. The GC/MS analysis of BO suggested Methyl Oleate (9.26%) as major compound. The HLBc was 12.1, wherein the correspondent emulsion showed a pH of 4.83±1.29, electrical conductivity of 103.65 µS, creaming rate of 2.51±0.54%, droplet size of 207.07±8.31 nm and polydispersity index of 0.212±0.005. The PPD showed different formulations characterized as O/W emulsions. Thus, the PPD proved to be a useful tool to produce BO emulsions, in which their constituents may vary within the range of the desired system.

Keywords: bullfrog (Rana catesbeiana Shaw) oil, emulsion production, hydrophilic-lipophilic balance, gas chromatography/mass spectrometry analysis

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176 Anecic and Epigeic Earthworms as Potential Biocontrol Agents of Fusarium graminearum, Causal Agent of Fusarium Head Blight on Wheat

Authors: Gabriella Jorge, Carlos A. Pérez, Hanna Friberg, Sara Söderlund, Jan Lagerlöf

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Fusarium Head Blight (FHB) is one of the most important Fusarium-caused diseases, which affects cereals with serious detrimental effects on yield and grain quality worldwide. Earthworms have been suggested as an alternative to control this disease, which requires a combination of preventive methods to reduce level of damage, although it has been proven that their effect is species dependent. Our objective was to evaluate the effect of the earthworms Aporrectodea longa and Lumbricus rubellus, on the inoculum of Fusarium graminearum on wheat straw. To test this we kept earthworms in vessels with soil, and F. graminearum-inoculated straw covering the surface, under controlled conditions for 6 weeks. Two factors were evaluated with a complete factorial design: earthworms (three levels: without earthworms, A. longa, and L. rubellus), and straw (two levels: inoculated with the pathogen, and sterile). The presence of L. rubellus significantly (P<0.05) reduced the amount of inoculated straw at the soil surface 31% after 6 weeks, while the presence of A. longa, most found in quiescence, did not have any significant effect on the amount of straw when compared to the control. After incubation, F. graminearum was detected by qPCR, only in the surface straw in those treatments inoculated with the pathogen but without earthworms. None of the treatments showed presence of Fusarium in the buried straw, soil or earthworm casts. Both earthworm species decreased in body weight during incubation, most likely due to the decrease in soil water content during the experiment, from 25% to 20%, and/or inadequate food supply, since no other source of food was added. However, this reduction in weight occurred indistinctly of the presence or not of Fusarium (P<0.05). This indicates that both species, of different ecological groups, anecic and epigeic, can reduce F. graminearum inoculum present in wheat straw, while their growth is not negatively affected by this pathogen. These promising results place A. longa, and L. rubellus as potential biocontrol agents of this fungal plant pathogen responsible for Fusarium Head Blight disease in wheat, although further ongoing experiments are needed to confirm the repeatability of these results.

Keywords: Aporrectodea longa, biological control, fungal plant pathogen, Lumbricus rubellus, qPCR, wheat straw

Procedia PDF Downloads 275
175 Xenografts: Successful Penetrating Keratoplasty Between Two Species

Authors: Francisco Alvarado, Luz Ramírez

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Corneal diseases are one of the main causes of visual impairment and affect almost 4 million, and this study assesses the effects of deep anterior lamellar keratoplasty (DALK) with porcine corneal stroma and postoperative topical treatment with tacrolimus in patients with infectious keratitis. No patient was observed with clinical graft rejection. Among the cases: 2 were positive to fungal culture, 2 with Aspergillus and the other 8 cases were confirmed by bacteriological culture. Corneal diseases are one of the main causes of visual impairment and affect almost 4 million. This study assesses the effects of deep anterior lamellar keratoplasty (DALK) with porcine corneal stroma and postoperative topical treatment with tacrolimus in patients with infectious keratitis. Receiver bed diameters ranged from 7.00 to 9.00 mm. No incidents of Descemet's membrane perforation were observed during surgery. During the follow-up period, no corneal graft splitting, IOP increase, or intolerance to tacrolimus were observed. Deep anterior lamellar keratoplasty seems to be the best option to avoid xenograft rejection, and it could help new surgical techniques in humans.

Keywords: ophthalmology, cornea, corneal transplant, xenografts, surgical innovations

Procedia PDF Downloads 85