Search results for: Natividad Natalia Angeles Manuel
177 Cultural Boundaries and Mental Health Stigma: A Systemic Review of Interventions to Reduce Opposition of Mental Health Services in Asian American Families
Authors: Tanya L. Patimeteeporn, Murali D. Nair
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There is a wide range of literature that suggests the factors that prevent Asian American families from utilizing mental health services. These factors arise from a combination of cultural perceptions of mental illness, and methods of treating them without the use of a mental health professional. Due to the increased awareness of Asian Americans’ stigmatization to mental health, there has been an effort to create culturally competent interventions for Asian American families that would reduce opposition to mental health services. Assessment of the effectiveness of these interventions reveals practices that integrate traditional healing methods with psychoeducation are more likely to promote receptiveness of mental health services by Asian American families. The documentary in this review, demonstrates these traditional healing methods from various ethnic enclaves in Los Angeles. In addition, mental health professionals who provide these interventions to Asian American families need to consider culture-bound syndromes and the various Asian health philosophies and belief systems in order to provide a culturally sensitive holistic treatment for their clients. However, because the literature on these interventions is limited, there is a need for a larger body of evidence to accurately assess the effectiveness of these culturally competent psychoeducation interventions.Keywords: Asian American, cultural boundaries, intervention, mental health stigma, psychoeducation, traditional healing
Procedia PDF Downloads 549176 Remote Observation of Environmental Parameters on the Surface of the Maricunga Salt Flat, Atacama Region, Chile
Authors: Lican Guzmán, José Manuel Lattus, Mariana Cervetto, Mauricio Calderón
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Today the estimation of effects produced by climate change in high Andean wetland environments is confronted by big challenges. This study provides a way to an analysis by remote sensing how some Ambiental aspects have evolved on the Maricunga salt flat in the last 30 years, divided into the summer and winter seasons, and if global warming is conditioning these changes. The first step to achieve this goal was the recompilation of geological, hydrological, and morphometric antecedents to ensure an adequate contextualization of its environmental parameters. After this, software processing and analysis of Landsat 5,7 and 8 satellite imagery was required to get the vegetation, water, surface temperature, and soil moisture indexes (NDVI, NDWI, LST, and SMI) in order to see how their spatial-temporal conditions have evolved in the area of study during recent decades. Results show a tendency of regular increase in surface temperature and disponibility of water during both seasons but with slight drought periods during summer. Soil moisture factor behaves as a constant during the dry season and with a tendency to increase during wintertime. Vegetation analysis shows an areal and quality increase of its surface sustained through time that is consistent with the increase of water supply and temperature in the basin mentioned before. Roughly, the effects of climate change can be described as positive for the Maricunga salt flat; however, the lack of exact correlation in dates of the imagery available to remote sensing analysis could be a factor for misleading in the interpretation of results.Keywords: global warming, geology, SIG, Atacama Desert, Salar de Maricunga, environmental geology, NDVI, SMI, LST, NDWI, Landsat
Procedia PDF Downloads 81175 Stun Practices in Swine in the Valle De Aburrá and Animal Welfare
Authors: Natalia Uribe Corrales, Carolina Cano Arroyave, Santiago Henao Villegas
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Introduction: Stunning is an important stage in the meat industry due to the repercussions on the characteristics of the carcass. It has been demonstrated that inadequate stun can lead to hematomas, fractures and promote the appearance of pale, soft and exudative meat due to the stress caused in animals. In Colombia, gas narcosis and electrical stunning are the two authorized methods in pigs. Objective: To describe the practices of stunning in the Valle de Aburrá and its relation with animal welfare. Methods: A descriptive cross - sectional study was carried out in Valle de Aburrá slaughterhouses, which were authorized by National Institute for Food and Medicine Surveillance (INVIMA). Variables such as stunning method, presence of vocalization, falls, slips, rhythmic breathing, corneal reflex and attempts to incorporate after stunning, stun time and time between stun and bleeding were analyzed. Results: 225 pigs were analyzed, finding that 50.2% had electrical stun, whose amperage and voltage were 1.23 (A) and 120 (V) respectively; 49.8% of the animals were stunned with CO2 chamber whose concentration was always above 95%, the mean desensitization time was 16.8 seconds (d.e.5.37); the mean time of stunning - bleeding was 47.9 seconds (d.e.13.9); similarly, it was found that 27.1% had vocalizations after stunning; 12% had falls; 10.7% showed rhythmic breathing; 33.3% exhibited corneal reflex; and 10.7% had reincorporation attempts. Conclusions: The methods of stunning used in the Valle de Aburrá, although performed with those permitted by law, are shortcomings in relation to the amperage and voltage used for each type of pig, as well, it is found that welfare animal is being violated to find signology of an inadequate desensitization. It is necessary to promote compliance with the principles of stunning according to Animal Welfare, and keep in mind that in electrical desensitization, the calibration of the equipment must be guaranteed (pressure according to the type of animal or current applied and the position where the electrodes are) and in the narcosis the equipment should be calibrated to ensure proper gas concentration and exposure time.Keywords: animal welfare, pigs, quality of meat, stun methods
Procedia PDF Downloads 223174 Impact of Massive Weight Loss Body Contouring Surgery in the Patient’s Quality of Life
Authors: Maria Albuquerque, Miguel Matias, Ângelo Sá, Juliana Sousa, Maria Manuel Mouzinho
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Obesity is a frequent disease in Portugal. The surgical treatment is very effective and has an indication when there is a failure of the medical treatment. Although massive weight loss is associated with considerable health gains, these patients are characterized by a variable degree of dermolipodistrophy. In some cases, there is even the development of physical symptoms such as intertriginous, and some degree of psychological distress is present. In almost all cases, a desire for a better body contour, which inhibits some aspects of social life, is a fact. A prospective study was made to access the impact of body contouring surgery in the quality of life of patients who underwent a massive weight lost correction surgical procedure at Centro Hospitalar de Lisboa Central between January 2020 and December 2021. The patients were submitted to the Body Q subjective questionnaire adapted for the Portuguese language and accessed for the following categories: Anguish with Appearance, Contempt with Body Image, Satisfaction with the Abdomen, and Overall Satisfaction with the Body. The questionnaire was repeated at the 6 months mark. A total of 80 patients were sampled. The sex distribution was 79 female and 1 male. The median BMI index before surgery was inferior to 28%. The pre operatory questionnaire showed high scores for Anguish with Appearance and low scores for the body image self-evaluation. Overall, there was an improvement of at least 50% in all the evaluated scores. Additionally, a correlation was found between abdominoplasty and the contempt with body image and satisfaction with the abdomen (p-value <0.05). Massive weight loss is associated with important body deformities that have a significant impact on the patient’s personal and social life. Body contouring surgery is then vital for these patients as it implicates major aesthetic and functional benefits.Keywords: abdominoplasty, cruroplasty, obesity, massive weight loss
Procedia PDF Downloads 158173 Management Practices in Holding Pens in Pig’s Slaughterhouses in the Valle De Aburrá, Antioquia and Animal Welfare
Authors: Natalia Uribe Corrales, Santiago Henao Villegas
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Introduction: The management of pigs in the holding pens at the slaughterhouses is a key point to minimize levels of stress and fear, improve efficiency, maintain a good quality of meat and avoid economic losses. Holding pens should guarantee drinking water continuously, a minimum space of 1.2 m2/ animal; As well as an adequate management in the conduction of the animals towards stun. Objective: To characterize the management practices in holding pens in slaughterhouses in the Valle de Aburrá. Methods: A descriptive cross - sectional study was carried out in Valle de Aburrá benefit plants, which were authorized by National Institute for Food and Medicine Surveillance (INVIMA). Variables such as management mechanisms to the pens, time of housing, water supply, load density, vocalization, slips and falls of the animals in the pens and mechanism of conduction towards desensitization were analyzed. Results: 225 pigs were analyzed, finding that 35.6% were lowered with slaps from the trucks to the waiting pens; The lairage time was greater than 10 hours in 16% of the animals; 12.9% of pigs had no water permanently; 40.9% was subjected to a high load density, while 19.6% had a low load density. Regarding aspects of animal welfare, 37.3% presented high vocalizations; 29.3% and 14.2% presented slips or falls respectively. Regarding the mechanism of conduction towards desensitization, slapping was used in 56% and electrical prod in 4%. Conclusions: It is necessary to continue promoting the learning of the densities of load, since both high and low densities generate inconveniences in animal welfare, favoring the appearance of lesions and stress in the animals. Also, to promote the rule of permanent water in the pens and a time of housing less than 10 hours. In relation to the driving mechanisms, it is necessary to continue animal husbandry campaigns, encouraging the use of other alternatives such as boards or panels to assist the movement of pigs.Keywords: animal welfare, quality of meat, swine, waiting pens
Procedia PDF Downloads 197172 The Mediating Role of Store Personality in the Relationship Between Self-Congruity and Manifestations of Loyalty
Authors: María de los Ángeles Crespo López, Carmen García García
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The highly competitive nature of today's globalised marketplace requires that brands and stores develop effective commercial strategies to ensure their economic survival. Maintaining the loyalty of existing customers constitutes one key strategy that yields the best results. Although the relationship between consumers' self-congruity and their manifestations of loyalty towards a store has been investigated, the role of store personality in this relationship remains unclear. In this study, multiple parallel mediation analysis was used to examine the effect of Store Personality on the relationship between Self-Congruity of consumers and their Manifestations of Loyalty. For this purpose, 457 Spanish consumers of the Fnac store completed three self-report questionnaires assessing Store Personality, Self-Congruity, and Store Loyalty. The data were analyzed using the SPSS macro PROCESS. The results revealed that three dimensions of Store Personality, namely Exciting, Close and Competent Store, positively and significantly mediated the relationship between Self-Congruity and Manifestations of Loyalty. The indirect effect of Competent Store was the greatest. This means that a consumer with higher levels of Self-Congruity with the store will exhibit more Manifestations of Loyalty when the store is perceived as Exciting, Close or Competent. These findings suggest that more attention should be paid to the perceived personality of stores for the development of effective marketing strategies to maintain or increase consumers' manifestations of loyalty towards stores.Keywords: multiple parallel mediation, PROCESS, self-congruence, store loyalty, store personality
Procedia PDF Downloads 160171 Development of Hybrid Materials Combining Biomass as Fique Fibers with Metal-Organic Frameworks, and Their Potential as Mercury Adsorbents
Authors: Karen G. Bastidas Gomez, Hugo R. Zea Ramirez, Manuel F. Ribeiro Pereira, Cesar A. Sierra Avila, Juan A. Clavijo Morales
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The contamination of water sources with heavy metals such as mercury has been an environmental problem; it has generated a high impact on the environment and human health. In countries such as Colombia, mercury contamination due to mining has reached levels much higher than the world average. This work proposes the use of fique fibers as adsorbent in mercury removal. The evaluation of the material was carried out under five different conditions (raw, pretreated by organosolv, functionalized by TEMPO oxidation, fiber functionalized plus MOF-199 and fiber functionalized plus MOF-199-SH). All the materials were characterized using FTIR, SEM, EDX, XRD, and TGA. Regarding the mercury removal, it was done under room pressure and temperature, also pH = 7 for all materials presentations, followed by Atomic Absorption Spectroscopy. The high cellulose content in fique is the main particularity of this lignocellulosic biomass since the degree of oxidation depends on the number of hydroxyl groups on the surface capable of oxidizing into carboxylic acids, a functional group capable of increasing ion exchange with mercury in solution. It was also expected that the impregnation of the MOF would increase the mercury removal; however, it was found that the functionalized fique achieved a greater percentage of removal, resulting in 81.33% of removal, 44% for the fique with the MOF-199 and 72% for the MOF-199-SH with. The pretreated fiber and raw also showed 74% and 56%, respectively, which indicates that fique does not require considerable modifications in its structure to achieve good performances. Even so, the functionalized fiber increases the percentage of removal considerably compared to the pretreated fique, which suggests that the functionalization process is a feasible procedure to apply with the purpose of improving the removal percentage. In addition, this is a procedure that follows a green approach since the reagents involved have low environmental impact, and the contribution to the remediation of natural resources is high.Keywords: biomass, nanotechnology, science materials, wastewater treatment
Procedia PDF Downloads 118170 An Empirical Study on the Impact of Peace in Tourists' Country of Origin on Their Travel Behavior
Authors: Claudia Seabra, Elisabeth Kastenholz, José Luís Abrantes, Manuel Reis
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In a world of increasing mobility and global risks, terrorism has, in a perverse way, capitalized on contemporaneous society’s growing interest in travel to explore a world whose national boundaries and distances have decreased. Terrorists have identified the modern tourist flows originated from the economically more developed countries as new appealing targets so as to: i) call attention to the causes they defend and ii) destroy a country’s foundations of tourism, with the final aim of disrupting the economic and consequently social fabric of the affected countries. The present study analyses sensitivity towards risk and travel behaviors in international travel amongst a sample of 600 international tourists from 49 countries travelling by air. Specifically, the sample was segmented according to the Global Peace Index. This index defines country profiles regarding the levels of peace. The indicators used are established over three broad themes: i) ongoing domestic and international conflict; ii) societal safety and security; and iii) militarisation. Tourists were segmented, according to their country of origin, in different levels of peacefulness. Several facets of travel behavior were evaluated, namely motivations, attitude towards trip planning, quality perception and perceived value of the trip. Also factors related with risk perception were evaluated, specifically terrorism risk perception during the trip, unsafety sensation as well as importance attributed to safety in travel. Results contribute to our understanding of the role of previous exposure to the lack of peace and safety at home in the international tourists behaviors, which is further discussed in terms of tourism management and marketing implications which should particularly interest tourism services and destinations more affected by terrorism, war, political turmoil, crime and other safety risks.Keywords: terrorism, tourism, safety, risk perception
Procedia PDF Downloads 441169 An Experimental Study of the External Thermal Insulation System’s (ETICS) Efficiency in Buildings during Spring Conditions
Authors: Carmen Viñas Arrebola, Antonio Rodriguez Sanchez, Sheila Varela Lujan, Mariano Gonzalez Cortina, Cesar Porras Amores
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The research group TEMA from the School of Building (UPM) is working in the line of energy efficiency and comfort in building. The need to reduce energy consumption in the building construction implies designing new constructive systems. These systems help to reduce both consumption and energy losses in order to achieve adequate thermal comfort for people in any type of building. In existing buildings the best option is the rehabilitation focused on thermal insulation. The aim of this paper is to design, monitor and analyze the first results of thermal behavior of the ETICS system in façades. This retrofitting solution consists of adding thermal insulation on the outside of the building, helping to create a continuous envelope on the façades. The analysis is done by comparing a rehabilitated part of the building with ETICS system and another part which has not been rehabilitated, and it is taken as reference. Both of them have the same characteristics. Temperature measurements were taken with type K thermocouples according to the previous design of the monitoring and in the same period of time. The pilot building of the study is situated in Benimamet Street, in San Cristobal de Los Ángeles, in the south of Madrid. It was built in the late 50s. The 51st entrance hall, which is restored, and the 47th entrance hall, in original conditions, have been studied.Keywords: comfort in building, energy efficiency in building, ETICS, thermal properties
Procedia PDF Downloads 316168 Electroencephalography Correlates of Memorability While Viewing Advertising Content
Authors: Victor N. Anisimov, Igor E. Serov, Ksenia M. Kolkova, Natalia V. Galkina
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The problem of memorability of the advertising content is closely connected with the key issues of neuromarketing. The memorability of the advertising content contributes to the marketing effectiveness of the promoted product. Significant directions of studying the phenomenon of memorability are the memorability of the brand (detected through the memorability of the logo) and the memorability of the product offer (detected through the memorization of dynamic audiovisual advertising content - commercial). The aim of this work is to reveal the predictors of memorization of static and dynamic audiovisual stimuli (logos and commercials). An important direction of the research was revealing differences in psychophysiological correlates of memorability between static and dynamic audiovisual stimuli. We assumed that static and dynamic images are perceived in different ways and may have a difference in the memorization process. Objective methods of recording psychophysiological parameters while watching static and dynamic audiovisual materials are well suited to achieve the aim. The electroencephalography (EEG) method was performed with the aim of identifying correlates of the memorability of various stimuli in the electrical activity of the cerebral cortex. All stimuli (in the groups of statics and dynamics separately) were divided into 2 groups – remembered and not remembered based on the results of the questioning method. The questionnaires were filled out by survey participants after viewing the stimuli not immediately, but after a time interval (for detecting stimuli recorded through long-term memorization). Using statistical method, we developed the classifier (statistical model) that predicts which group (remembered or not remembered) stimuli gets, based on psychophysiological perception. The result of the statistical model was compared with the results of the questionnaire. Conclusions: Predictors of the memorability of static and dynamic stimuli have been identified, which allows prediction of which stimuli will have a higher probability of remembering. Further developments of this study will be the creation of stimulus memory model with the possibility of recognizing the stimulus as previously seen or new. Thus, in the process of remembering the stimulus, it is planned to take into account the stimulus recognition factor, which is one of the most important tasks for neuromarketing.Keywords: memory, commercials, neuromarketing, EEG, branding
Procedia PDF Downloads 251167 A Thematic Analysis on the Drivers of Community Participation for River Restoration Projects, the Case of Kerala, India
Authors: Alvin Manuel Vazhayil, Chaozhong Tan, Karl M. Wantzen
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As local community participation in river restoration projects is increasingly recognized to be crucial for sustainable outcomes, researchers are exploring factors that motivate community participation globally. In India, while there is consensus in literature on the importance of community engagement in river restoration projects, research on what drives local communities to participate is limited, especially given the societal and economic challenges common in the Global South. This study addresses this gap by exploring the drivers of community participation in the local river restoration initiatives of the "Now Let Me Flow" campaign in Kerala, India. The project aimed to restore 87,000 kilometers of streams through the middle-ground governance approach that integrated bottom-up community efforts with top-down governmental support. The fieldwork involved interviews with 26 key agents, including local leaders, policy practitioners, politicians, and environmental activists associated with the project, and the collection of secondary data from 12 documents including project reports and news articles. The data was analyzed in NVivo (NVivo 11 Plus for Windows, version 11.3.0.773) using thematic analysis which included two cycles of systematic coding. The findings reveal two main drivers influencing community participation: top-down actions from local governments, and bottom-up drivers within the community. The study highlights the importance of local stakeholder collaboration, support of local governments, and local community engagement in successful river restoration projects. These findings are consistent with other empirical studies on participatory environmental problem-solving globally. The results offer crucial insights for policymakers and governments to better design and implement effective and sustainable participatory river restoration projects.Keywords: community initiatives, drivers of participation, environmental governance, river restoration
Procedia PDF Downloads 30166 Road Traffic Accidents Analysis in Mexico City through Crowdsourcing Data and Data Mining Techniques
Authors: Gabriela V. Angeles Perez, Jose Castillejos Lopez, Araceli L. Reyes Cabello, Emilio Bravo Grajales, Adriana Perez Espinosa, Jose L. Quiroz Fabian
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Road traffic accidents are among the principal causes of traffic congestion, causing human losses, damages to health and the environment, economic losses and material damages. Studies about traditional road traffic accidents in urban zones represents very high inversion of time and money, additionally, the result are not current. However, nowadays in many countries, the crowdsourced GPS based traffic and navigation apps have emerged as an important source of information to low cost to studies of road traffic accidents and urban congestion caused by them. In this article we identified the zones, roads and specific time in the CDMX in which the largest number of road traffic accidents are concentrated during 2016. We built a database compiling information obtained from the social network known as Waze. The methodology employed was Discovery of knowledge in the database (KDD) for the discovery of patterns in the accidents reports. Furthermore, using data mining techniques with the help of Weka. The selected algorithms was the Maximization of Expectations (EM) to obtain the number ideal of clusters for the data and k-means as a grouping method. Finally, the results were visualized with the Geographic Information System QGIS.Keywords: data mining, k-means, road traffic accidents, Waze, Weka
Procedia PDF Downloads 418165 Recycling of End of Life Concrete Based on C2CA Method
Authors: Somayeh Lotfi, Manuel Eggimann, Eckhard Wagner, Radosław Mróz, Jan Deja
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One of the main environmental challenges in the construction industry is a strong social force to decrease the bulk transport of the building materials in urban environments. Considering this fact, applying more in-situ recycling technologies for Construction and Demolition Waste (CDW) is an urgent need. The European C2CA project develops a novel concrete recycling technology that can be performed purely mechanically and in situ. The technology consists of a combination of smart demolition, gentle grinding of the crushed concrete in an autogenous mill, and a novel dry classification technology called ADR to remove the fines. The feasibility of this recycling process was examined in demonstration projects involving in total 20,000 tons of End of Life (EOL) concrete from two office towers in Groningen, The Netherlands. This paper concentrates on the second demonstration project of C2CA, where EOL concrete was recycled on an industrial site. After recycling, the properties of the produced Recycled Aggregate (RA) were investigated, and results are presented. An experimental study was carried out on mechanical and durability properties of produced Recycled Aggregate Concrete (RAC) compared to those of the Natural Aggregate Concrete (NAC). The aim was to understand the importance of RA substitution, w/c ratio and type of cement to the properties of RAC. In this regard, two series of reference concrete with strength classes of C25/30 and C45/55 were produced using natural coarse aggregates (rounded and crushed) and natural sand. The RAC series were created by replacing parts of the natural aggregate, resulting in series of concrete with 0%, 20%, 50% and 100% of RA. Results show that the concrete mix design and type of cement have a decisive effect on the properties of RAC. On the other hand, the substitution of RA even at a high percentage replacement level has a minor and manageable impact on the performance of RAC. This result is a good indication towards the feasibility of using RA in structural concrete by modifying the mix design and using a proper type of cement.Keywords: C2CA, ADR, concrete recycling, recycled aggregate, durability
Procedia PDF Downloads 392164 Obtaining Triploid Plants of Sprekelia formosissima by Artificial Hybridization
Authors: Jose Manuel Rodriguez-Dominguez, Rodrigo Barba-Gonzalez, Ernesto Tapia-Campos
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Sprekelia formosissima (L.) Herbert is a bulbous ornamental species of the monocotyledonous Amaryllidaceae family, and it is a perennial, herbaceous monotypic plant commonly known as ‘Aztec Lily’ or ‘Jacobean Lily’; it is distributed through Mexico and Guatemala. Its scarlet flowers with curved petals have made it an exceptional ornamental pot plant. Cytogenetic studies in this species have shown differences in chromosome number (2n=60, 120, 150, 180) with a basic number x=30. Different reports have shown a variable ploidy level (diploid, tetraploid, pentaploid and hexaploid); however, triploid plants have not been reported. In this work, triploid plants of S. formosissima were obtained by crossing tetraploid (2n=4x=120) with diploid (2n=2x=60) genotypes of this species; the seeds obtained from the crosses were placed in pots with a moist substrate made of Peat Moss: Vermiculite (7:3) for germination. Root tips were collected, and metaphasic chromosome preparations were performed. For chromosome counting, the best five metaphases obtained were photographed with a Leica DMRA2 microscope (Leica Microsystems, Germany) microscopy coupled to an Evolution QEI camera under phase contrast (Media-Cybernetics). Chromosomes counting in root-tip cells showed that 100% of the plants were triploid (2n=3x=90). Although tetraploid or pentaploid plants of S. formosissima are highly appreciated, they usually have lower growth rates than related diploid ones. For this reason, it is important to obtain triploid plants, which have advantages such as higher growth rates than tetraploid and pentaploid, larger flowers than those of the diploid plants and they are expected to not be able to produce seeds because their gametes are aneuploids. Furthermore, triploids may become very important for genomic research in the future, creating opportunities for discovering and monitoring genomic and transcriptomic changes in unbalanced genomes, hence the importance of this work.Keywords: Amaryllidaceae, cytogenetics, ornamental, ploidy level
Procedia PDF Downloads 194163 Photodegradation of Profoxydim Herbicide in Amended Paddy Soil-Water System
Authors: A. Cervantes-Diaz, B. Sevilla-Moran, Manuel Alcami, Al Mokhtar Lamsabhi, J. L. Alonso-Prados, P. Sandin-España
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Profoxydim is a post-emergence herbicide belonging to the cyclohexanedione oxime family, used to control weeds in rice crops. The use of soil organic amendments has increased significantly in the last decades, and their effects on the behavior of many herbicides are still unknown. Additionally, it is known that photolysis is an important degradation process to be considered when evaluating the persistence of this family of herbicides in the environment. In this work, the photodegradation of profoxydim in an amended paddy soil-water system with alperujo compost was studied. Photodegradation experiments were carried out under laboratory conditions using simulated solar light (Suntest equipment) in order to evaluate the reaction kinetics of the active substance. The photochemical behavior of profoxydim was investigated in soil with and without alperujo amendment. Furthermore, due to the rice crop characteristics, profoxydim photodegradation in water in contact with these types of soils was also studied. Determination of profoxydim degradation kinetics was performed by High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). Furthermore, we followed the evolution of resulting transformation by-products, and their tentative identification was achieved by mass spectrometry. All the experiments allowed us to fit the data of profoxydim photodegradation to a first-order kinetic. Photodegradation of profoxydim was very rapid in all cases. The half-lives in aqueous matrices were in the range of 86±0.3 to 103±0.5 min. The addition of alperujo amendment to the soil produced an increase in the half-life from 62±0.2 min (soil) to 75±0.3 min (amended soil). In addition, a comparison to other organic amendments was also performed. Results showed that the presence of the organic amendment retarded the photodegradation in paddy soil and water. Regarding degradation products, the main process involved was the cleavage of the oxime moiety giving rise to the formation of the corresponding imine compound.Keywords: by-products, herbicide, organic amendment, photodegradation, profoxydim
Procedia PDF Downloads 81162 PlayTrain: A Research and Intervention Project for Early Childhood Teacher Education
Authors: Dalila Lino, Maria Joao Hortas, Carla Rocha, Clarisse Nunes, Natalia Vieira, Marina Fuertes, Kátia Sa
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The value of play is recognized worldwide and is considered a fundamental right of all children, as defined in Article 31 of the United Nations Children’s Rights. It is consensual among the scientific community that play, and toys are of vital importance for children’s learning and development. Play promotes the acquisition of language, enhances creativity and improves social, affective, emotional, cognitive and motor development of young children. Young children ages 0 to 6 who have had many opportunities to get involved in play show greater competence to adapt to new and unexpected situations and more easily overcome the pain and suffering caused by traumatic situations. The PlayTrain Project aims to understand the places/spaces of play in the education of children from 0 to 6 years and promoting the training of preschool teachers to become capable of developing practices that enhance children’s agency, experimentation in the physical and social world and the development of imagination and creativity. This project follows the Design-Based-Research (DBR) and has two dimensions: research and intervention. The participants are 120 students from the Master in Pre-school Education of the Higher School of Education, Polytechnic Institute of Lisbon enrolled in the academic year 2018/2019. The development of workshops focused on the role of play and toys for young children’s learning promotes the participants reflection and the development of skills and knowledge to construct developmentally appropriated practices in early childhood education. Data was collected through an online questionnaire and focal groups. Results show that the PlayTrain Project contribute to the development of a body of knowledge about the role of play for early childhood education. It was possible to identify the needs of preschool teacher education and to enhance the discussion among the scientific and academic community about the importance of deepening the role of play and toys in the study plans of the masters in pre-school education.Keywords: children's learning, early childhood education, play, teacher education, toys
Procedia PDF Downloads 144161 The Systems Biology Verification Endeavor: Harness the Power of the Crowd to Address Computational and Biological Challenges
Authors: Stephanie Boue, Nicolas Sierro, Julia Hoeng, Manuel C. Peitsch
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Systems biology relies on large numbers of data points and sophisticated methods to extract biologically meaningful signal and mechanistic understanding. For example, analyses of transcriptomics and proteomics data enable to gain insights into the molecular differences in tissues exposed to diverse stimuli or test items. Whereas the interpretation of endpoints specifically measuring a mechanism is relatively straightforward, the interpretation of big data is more complex and would benefit from comparing results obtained with diverse analysis methods. The sbv IMPROVER project was created to implement solutions to verify systems biology data, methods, and conclusions. Computational challenges leveraging the wisdom of the crowd allow benchmarking methods for specific tasks, such as signature extraction and/or samples classification. Four challenges have already been successfully conducted and confirmed that the aggregation of predictions often leads to better results than individual predictions and that methods perform best in specific contexts. Whenever the scientific question of interest does not have a gold standard, but may greatly benefit from the scientific community to come together and discuss their approaches and results, datathons are set up. The inaugural sbv IMPROVER datathon was held in Singapore on 23-24 September 2016. It allowed bioinformaticians and data scientists to consolidate their ideas and work on the most promising methods as teams, after having initially reflected on the problem on their own. The outcome is a set of visualization and analysis methods that will be shared with the scientific community via the Garuda platform, an open connectivity platform that provides a framework to navigate through different applications, databases and services in biology and medicine. We will present the results we obtained when analyzing data with our network-based method, and introduce a datathon that will take place in Japan to encourage the analysis of the same datasets with other methods to allow for the consolidation of conclusions.Keywords: big data interpretation, datathon, systems toxicology, verification
Procedia PDF Downloads 278160 Analyzing the Impact of Board Diversity on Firm Performance: Case Study of the Nigerian Banking Sector
Authors: Data Collete Bob-Manuel
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In light of global financial crisis in 2007-2008 various factors including board diversity, succession planning and board evaluation have been identified as essential ingredients in ensuring board effectiveness. The composition and structure of the board is of outmost importance in assessing a board’s ability and success in achieving its objectives. Following the corporate frauds and accounting scandals such as Enron, WorldCom, Parmalat, Oceanic Bank Nigeria and AfriBank Nigeria, there has been a notable amount of research about the effectiveness of the board of directors in the corporate governance of firms. The need to have an effective board cannot be over emphasized as it results in a more stable and thriving company. There has been an overarching need in the business world for a more diverse workforce and board of directors. Big corporations like Texaco, Ford Motors and DuPont have stated how diversity at every level of the workforce including the board of directors has been cited as a vital element for a company to succeed. Developed countries are also seeking for companies to have a more diverse board. For instance Norway has implemented a 60:40 board ratio to all companies. In West Africa, particularly Nigeria, the topic of diversity has received little attention as most studies conducted have focused on the gender aspect of diversity, which results found to have a negative impact on firm performance. This paper seeks to examine four variables of diversity; age, ethnicity, gender and skills to weigh the positive or negative impact the variables have on firm performance, based on evidence from the Nigerian Financial sector. Information used for this study will be gathered from financial statements and annual reports so as to enable the researcher to reflect on past years to know what is being done differently today. The findings of this study will help the researcher to develop a working definition for ethnicity with regards to the West African context where the issue of “tribe” is a sensitive topic.Keywords: Board of Directors, Board Diversity, Firm Performance, Nigeria
Procedia PDF Downloads 398159 Systematic Identification and Quantification of Substrate Specificity Determinants in Human Protein Kinases
Authors: Manuel A. Alonso-Tarajano, Roberto Mosca, Patrick Aloy
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Protein kinases participate in a myriad of cellular processes of major biomedical interest. The in vivo substrate specificity of these enzymes is a process determined by several factors, and despite several years of research on the topic, is still far from being totally understood. In the present work, we have quantified the contributions to the kinase substrate specificity of i) the phosphorylation sites and their surrounding residues in the sequence and of ii) the association of kinases to adaptor or scaffold proteins. We have used position-specific scoring matrices (PSSMs), to represent the stretches of sequences phosphorylated by 93 families of kinases. We have found negative correlations between the number of sequences from which a PSSM is generated and the statistical significance and the performance of that PSSM. Using a subset of 22 statistically significant PSSMs, we have identified specificity determinant residues (SDRs) for 86% of the corresponding kinase families. Our results suggest that different SDRs can function as positive or negative elements of substrate recognition by the different families of kinases. Additionally, we have found that human proteins with known function as adaptors or scaffolds (kAS) tend to interact with a significantly large fraction of the substrates of the kinases to which they associate. Based on this characteristic we have identified a set of 279 potential adaptors/scaffolds (pAS) for human kinases, which is enriched in Pfam domains and functional terms tightly related to the proposed function. Moreover, our results show that for 74.6% of the kinase– pAS association found, the pAS colocalize with the substrates of the kinases they are associated to. Finally, we have found evidence suggesting that the association of kinases to adaptors and scaffolds, may contribute significantly to diminish the in vivo substrate crossed- specificity of protein kinases. In general, our results indicate the relevance of several SDRs for both the positive and negative selection of phosphorylation sites by kinase families and also suggest that the association of kinases to pAS proteins may be an important factor for the localization of the enzymes with their set of substrates.Keywords: kinase, phosphorylation, substrate specificity, adaptors, scaffolds, cellular colocalization
Procedia PDF Downloads 344158 Laser - Ultrasonic Method for the Measurement of Residual Stresses in Metals
Authors: Alexander A. Karabutov, Natalia B. Podymova, Elena B. Cherepetskaya
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The theoretical analysis is carried out to get the relation between the ultrasonic wave velocity and the value of residual stresses. The laser-ultrasonic method is developed to evaluate the residual stresses and subsurface defects in metals. The method is based on the laser thermooptical excitation of longitudinal ultrasonic wave sand their detection by a broadband piezoelectric detector. A laser pulse with the time duration of 8 ns of the full width at half of maximum and with the energy of 300 µJ is absorbed in a thin layer of the special generator that is inclined relative to the object under study. The non-uniform heating of the generator causes the formation of a broadband powerful pulse of longitudinal ultrasonic waves. It is shown that the temporal profile of this pulse is the convolution of the temporal envelope of the laser pulse and the profile of the in-depth distribution of the heat sources. The ultrasonic waves reach the surface of the object through the prism that serves as an acoustic duct. At the interface ‚laser-ultrasonic transducer-object‘ the conversion of the most part of the longitudinal wave energy takes place into the shear, subsurface longitudinal and Rayleigh waves. They spread within the subsurface layer of the studied object and are detected by the piezoelectric detector. The electrical signal that corresponds to the detected acoustic signal is acquired by an analog-to-digital converter and when is mathematically processed and visualized with a personal computer. The distance between the generator and the piezodetector as well as the spread times of acoustic waves in the acoustic ducts are the characteristic parameters of the laser-ultrasonic transducer and are determined using the calibration samples. There lative precision of the measurement of the velocity of longitudinal ultrasonic waves is 0.05% that corresponds to approximately ±3 m/s for the steels of conventional quality. This precision allows one to determine the mechanical stress in the steel samples with the minimal detection threshold of approximately 22.7 MPa. The results are presented for the measured dependencies of the velocity of longitudinal ultrasonic waves in the samples on the values of the applied compression stress in the range of 20-100 MPa.Keywords: laser-ultrasonic method, longitudinal ultrasonic waves, metals, residual stresses
Procedia PDF Downloads 326157 Islamophobia, Years After 9/11: An Assessment of the American Media
Authors: Nasa'i Muhammad Gwadabe
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This study seeks to find the extent to which the old Islamophobic prejudice was tilted towards a more negative direction in the United States following the 9/11 terrorist attacks. It is hypothesized that, the 9/11 attacks in the United States reshaped the old Islamophobic prejudice through the reinforcement of a strong social identity construction of Muslims as “out-group”. The “social identity” and “discourse representation” theories are used as framework for analysis. To test the hypothesis, two categories were created: the prejudice (out-group) and the tolerance (in-group) categories. The Prejudice (out-group) against Muslims category was coded to include six attributes: (Terrorist, Threat, Women's Rights violation, Undemocratic, Backward and Intolerant); while the tolerance (In-group) for Muslims category was also coded to include six attributes: (Peaceful, civilized, educated, partners trustworthy and honest). Data are generated from the archives of three American newspapers: The Los Angeles Times, New York Times and USA Today using specific search terms and specific date range; from 9/11/1996 to 9/11/2006, that is five years before and five years after the 9/11. An aggregate of 20595 articles were generated from the search of the three newspapers throughout the search periods. Conclusively, for both pre and post 9/11 periods, the articles generated under the category of prejudice (out-group) against Muslims revealed a higher frequency, against that of tolerance (in-group) for them, which is lesser. Finally, The comparison between the pre and post 9/11 periods showed that, the increased Prejudice (out-group) against Muslims was most influenced through libeling them as terrorist, which signaled a skyrocketed increase from pre to post 9/11.Keywords: in-group, Islam, Islamophobia, Muslims, out-group, prejudice, terrorism, the 9/11 and tolerance
Procedia PDF Downloads 307156 Disability Policy and Leaders in México
Authors: Jennifer Isabelle Rios Rendón, Ursula Sanchez, Dana Lee Baker
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Disability Policy in México has witnessed numerous changed throughout the years. Physical disabilities are more often recognized in Mexican culture. However, with an emerging focus on neurological disabilities or differences in individuals’ new policies are needed to serve better and understand the needs of these populations. The need to understand and communicate with local leaders is imperative, as the lens used to analyze autism has historically been from a Western school of thought. We are looking to comprehend the disability policy subsystem in México - specifically how autism is perceived, the language used to describe it, and how it ties to the cultural stigma of disabilities that exist in México. Therefore, to understand this, we seek to interview multiple policy leaders on their experience in autism and disability policy. The goal is to conduct qualitative research through interviews with local autism and disability leaders in México. This methodology aims to answer the questions of what language commonly and culturally is utilized in disability policy, the context of how autism is perceived in México, and in general, the lived experience of the disability policy leaders that take part in this effort in México. Local activists and policy leaders were initially found through an online search then collected using snowball sampling. The interviews were conducted through a series of pre-formulated questions that the policy leader answered via email or a phone conversation with the researchers. Acknowledging the importance of language and accessibility, the need for the content to be in both English and Spanish as well as auditory and visual is essential to take steps in the inclusion of a Neurodiverse group of leaders. This work is a demonstration of the framework of the investigation which hopes to create a more complete understanding of the policy and political culture around autism in México. Results of the project include new insight into the developing relationship between the President Andrés Manuel López Obrador’s administration, disability activists, and neurodiverse communities. The project contributes to denormalizing the legacy of white supremacy in autism related, historically rooted in the assumption that autism occurs predominantly in white communities.Keywords: autism, disability leaders, disability policy, México, Neurodiversity
Procedia PDF Downloads 137155 Study of the Suitability for the Use of Gravel in the Regions around Araz River in Karabakh as a Concrete Aggregate
Authors: S. B. Shahmarova, F. N. Iskandarli, J. T. Zeynalov, F. N. Mammadov, M. M. Mirzayev, F. Y. Bayramov
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The physical, mechanical, and chemical properties of aggregates play an important role in the production of ready-mixed concrete. Furthermore, the alkali-silicate reaction of aggregates is one of the essential factors in construction projects for the durability and longer service life of buildings and construction structures to be built. It is necessary to use the aggregates from the liberated regions of Karabakh and East Zangazur in the preparation of concretes to be produced for reconstruction and renovation projects in those regions. In this regard, the study of the physical and mechanical properties of aggregates in the regions around the Araz River (Fuzuli, Jabrayil, and Zangilan) became a significant issue. So, gravel samples were taken from seven different sources located in the regions around Araz River, where the quarries are planned to be built. The chemical oxide composition of the samples was determined, water absorption and specific gravity tests, chloride, alkali-silicate reaction tests, aggregate crushing strength test, Los Angeles, and frost resistance (into the solution of MgSO₄ and Na₂SO₄) tests were performed, and the results were evaluated in accordance with the relevant standards. As a result, it was determined that the aggregates in the regions around the Araz River (Fuzuli, Jabrayil, and Zangilan) conform to the relative standards and can be used effectively in the production of various concretes to be used for the projects in Karabakh.Keywords: aggregates of the regions around Araz River (Fuzuli, Jabrayil, and Zangilan), physical and mechanical properties, alkali-silicate reaction, Karabakh, Azerbaijan
Procedia PDF Downloads 93154 Spatial Mental Imagery in Students with Visual Impairments when Learning Literal and Metaphorical Uses of Prepositions in English as a Foreign Language
Authors: Natalia Sáez, Dina Shulfman
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There is an important research gap regarding accessible pedagogical techniques for teaching foreign languages to adults with visual impairments. English as a foreign language (EFL), in particular, is needed in many countries to expand occupational opportunities and improve living standards. Within EFL research, teaching and learning prepositions have only recently gained momentum, considering that they constitute one of the most difficult structures to learn in a foreign language and are fundamental for communicating about spatial relations in the world, both on the physical and imaginary levels. Learning to use prepositions would not only facilitate communication when referring to the surrounding tangible environment but also when conveying ideas about abstract topics (e.g., justice, love, society), for which students’ sociocultural knowledge about space could play an important role. By potentiating visually impaired students’ ability to construe mental spatial imagery, this study made efforts to explore pedagogical techniques that cater to their strengths, helping them create new worlds by welcoming and expanding their sociocultural funds of knowledge as they learn to use English prepositions. Fifteen visually impaired adults living in Chile participated in the study. Their first language was Spanish, and they were learning English at the intermediate level of proficiency in an EFL workshop at La Biblioteca Central para Ciegos (The Central Library for the Blind). Within this workshop, a series of activities and interviews were designed and implemented with the intention of uncovering students’ spatial funds of knowledge when learning literal/physical uses of three English prepositions, namely “in,” “at,” and “on”. The activities and interviews also explored whether students used their original spatial funds of knowledge when learning metaphorical uses of these prepositions and if their use of spatial imagery changed throughout the learning activities. Over the course of approximately half a year, it soon became clear that the students construed mental images of space when learning both literal/physical and metaphorical uses of these prepositions. This research could inform a new approach to inclusive language education using pedagogical methods that are relevant and accessible to students with visual impairments.Keywords: EFL, funds of knowledge, prepositions, spatial cognition, visually impaired students
Procedia PDF Downloads 82153 Anticancer Study of Copper and Zinc Complexes with Doxorubicin
Authors: Grzegorz Swiderski, Agata Jablonska-Trypuc, Natalia Popow, Renata Swislocka, Wlodzimierz Lewandowski
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Doxorubicin belongs to the group of anthracycline antitumor antibiotics. Because of the wide spectrum of actions, it is one of the most widely used anthracycline antibiotics, including the treatment of breast, ovary, bladder, lung cancers as well as neuroblastoma, lymphoma, leukemia and myeloid leukemia. Antitumor activity of doxorubicin is based on the same mechanisms as for most anthracyclines. Like the metal ions affect the nucleic acids on many biological processes, so the environment of the metal chelates of antibiotics can have a significant effect on the pharmacological properties of drugs. Complexation of anthracyclines with metal ions may contribute to the production of less toxic compounds. In the framework of this study, the composition of complexes obtained in aqueous solutions of doxorubicin with metal ions (Cu2+ and Zn2+). Complexation was analyzed by spectrophotometric titration in aqueous solution at pH 7.0. The pH was adjusted with 0.02M Tris-HCl buffer. The composition of the complexes found was Cu: doxorubicin (1: 2) and a Zn: doxorubicin (1: 1). The effect of Dox, Dox-Cu and Dox-Zn was examined in MCF-7 breast cancer cell line, which were obtained from American Type Culture Collection (ATCC). The compounds were added to the cultured cells for a final concentration in the range of 0,01µM to 0,5µM. The number of MCF-7 cells with division into living and dead, was determined by direct counts of cells with the use of trypan blue dye using LUNA Logos Biosystems cell counter. ApoTox-Glo Triplex Assay (Promega, Madison, Wisconsin, USA) was used according to the manufacturer’s instructions to measure the MCF-7 cells’ viability, cytotoxicity and apoptosis. We observed a decrease in cells proliferation in a dose-dependent manner. An increase in cytotoxicity and decrease in viability in the ApoTox Triplex assay was also showed for all tested compounds. Apoptosis, showed as caspase 3/7 activation, was observed only in Dox treatment. In Dox-Zn and Dox-Cu caspase 3/7 activation was not observed. This work was financially supported by National Science Centre, Poland, under the research project number 2014/13/B/NZ7/02 352.Keywords: anticancer properties, anthracycline antibiotic, doxorubicine, metal complexes
Procedia PDF Downloads 281152 Spatial Temporal Change of COVID-19 Vaccination Condition in the US: An Exploration Based on Space Time Cube
Authors: Yue Hao
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COVID-19 vaccines not only protect individuals but society as a whole. In this case, having an understanding of the change and trend of vaccination conditions may shed some light on revising and making up-to-date policies regarding large-scale public health promotions and calls in order to lead and encourage the adoption of COVID-19 vaccines. However, vaccination status change over time and vary from place to place hidden patterns that were not fully explored in previous research. In our research, we took advantage of the spatial-temporal analytical methods in the domain of geographic information science and captured the spatial-temporal changes regarding COVID-19 vaccination status in the United States during 2020 and 2021. After conducting the emerging hot spots analysis on both the state level data of the US and county level data of California we found that: (1) at the macroscopic level, there is a continuously increasing trend of the vaccination rate in the US, but there is a variance on the spatial clusters at county level; (2) spatial hotspots and clusters with high vaccination amount over time were clustered around the west and east coast in regions like California and New York City where are densely populated with considerable economy conditions; (3) in terms of the growing trend of the daily vaccination among, Los Angeles County alone has very high statistics and dramatic increases over time. We hope that our findings can be valuable guidance for supporting future decision-making regarding vaccination policies as well as directing new research on relevant topics.Keywords: COVID-19 vaccine, GIS, space time cube, spatial-temporal analysis
Procedia PDF Downloads 81151 Nonlinear Evolution of the Pulses of Elastic Waves in Geological Materials
Authors: Elena B. Cherepetskaya, Alexander A. Karabutov, Natalia B. Podymova, Ivan Sas
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Nonlinear evolution of broadband ultrasonic pulses passed through the rock specimens is studied using the apparatus ‘GEOSCAN-02M’. Ultrasonic pulses are excited by the pulses of Q-switched Nd:YAG laser with the time duration of 10 ns and with the energy of 260 mJ. This energy can be reduced to 20 mJ by some light filters. The laser beam radius did not exceed 5 mm. As a result of the absorption of the laser pulse in the special material – the optoacoustic generator–the pulses of longitudinal ultrasonic waves are excited with the time duration of 100 ns and with the maximum pressure amplitude of 10 MPa. The immersion technique is used to measure the parameters of these ultrasonic pulses passed through a specimen, the immersion liquid is distilled water. The reference pulse passed through the cell with water has the compression and the rarefaction phases. The amplitude of the rarefaction phase is five times lower than that of the compression phase. The spectral range of the reference pulse reaches 10 MHz. The cubic-shaped specimens of the Karelian gabbro are studied with the rib length 3 cm. The ultimate strength of the specimens by the uniaxial compression is (300±10) MPa. As the reference pulse passes through the area of the specimen without cracks the compression phase decreases and the rarefaction one increases due to diffraction and scattering of ultrasound, so the ratio of these phases becomes 2.3:1. After preloading some horizontal cracks appear in the specimens. Their location is found by one-sided scanning of the specimen using the backward mode detection of the ultrasonic pulses reflected from the structure defects. Using the computer processing of these signals the images are obtained of the cross-sections of the specimens with cracks. By the increase of the reference pulse amplitude from 0.1 MPa to 5 MPa the nonlinear transformation of the ultrasonic pulse passed through the specimen with horizontal cracks results in the decrease by 2.5 times of the amplitude of the rarefaction phase and in the increase of its duration by 2.1 times. By the increase of the reference pulse amplitude from 5 MPa to 10 MPa the time splitting of the phases is observed for the bipolar pulse passed through the specimen. The compression and rarefaction phases propagate with different velocities. These features of the powerful broadband ultrasonic pulses passed through the rock specimens can be described by the hysteresis model of Preisach-Mayergoyz and can be used for the location of cracks in the optically opaque materials.Keywords: cracks, geological materials, nonlinear evolution of ultrasonic pulses, rock
Procedia PDF Downloads 351150 Achieving Quality of Life and Sustainability in Mexican Cities, the Case of the Housing Complex “Villa del Campo”, Tijuana, Mexico
Authors: María de los Ángeles Zárate López, Juan Antonio Pitones Rubio
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Quality of life and sustainability in cities are among the most important challenges faced by designers, city planners and urban managers. The Mexican city of Tijuana has a particular dynamic in its demographics which has been accelerated by its border city condition, putting to the test the ability from authorities to provide the population with the necessary services to aspire for a deserving quality of life. In the recent story of Tijuana, we found that the housing policy and the solutions presented by private housing developers have not met the best living conditions for end users by far, thereby adding issues to current social problems which impact the whole metropolitan area, including damage to the natural environment. Therefore this research presents the case study about the situation of a suburban housing development near Tijuana named “Villa del Campo” and exposes the problems of this specific project (originally labelled as a “sustainable” proposal) demonstrating that, once built, the place does not reflect the quality of life that it promised as a project. Currently, this housing development has a number of problematic issues such as the faulty operating conditions of public utilities and serious cases of crime inside the neighborhood. There is no intention to only expose the negative side of this case study, but to explore some alternatives which could help solving the most serious problems at the place, considering possible architectural and landscape interventions within the housing complex to help achieve the optimal conditions of livability and sustainability required by their inhabitants.Keywords: suburban, housing, quality of life, sustainability, Tijuana, demographics
Procedia PDF Downloads 385149 Deep Cryogenic Treatment With Subsequent Aging Applied to Martensitic Stainless Steel: Evaluation of Hardness, Tenacity and Microstructure
Authors: Victor Manuel Alcántara Alza
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The way in which the application of the deep cryogenic treatment DCT(-196°C) affects, applied with subsequent aging, was investigated, regarding the mechanical properties of hardness, toughness and microstructure, applied to martensitic stainless steels, with the aim of establishing a different methodology compared to the traditional DCT cryogenic treatment with subsequent tempering. For this experimental study, a muffle furnace was used, first subjecting the specimens to deep cryogenization in a liquid Nitrogen bath/4h, after being previously austenitized at the following temperatures: 1020-1030-1040-1050 (°C) / 1 hour; and then tempered in oil. A first group of cryogenic samples were subjected to subsequent aging at 150°C, with immersion times: 2.5 -5- 10 - 20 - 50 – 100 (h). The next group was subjected to subsequent tempering at temperatures: 480-500-510-520-530-540 (°C)/ 2h. The hardness tests were carried out under standards, using a Universal Durometer, and the readings were made on the HRC scale. The Impact Resistance tests were carried out in a Charpy machine following the ASTM E 23 – 93ª standard. Measurements were taken in joules. Microscopy was performed at the optical level using a 1000X microscope. It was found: For the entire aging interval, the samples austenitized at 1050°C present greater hardness than austenitized at 1040°C, with the maximum peak aged being at 30h. In all cases, the aged samples exceed the hardness of the tempered samples, even in their minimum values. In post-tempered samples, the tempering temperature hardly have effect on the impact strength of material. In the Cryogenic Treatment: DCT + subsequent aging, the maximum hardness value (58.7 HRC) is linked to an impact toughness value (54J) obtained with aging time of 39h, which is considered an optimal condition. The higher hardness of steel after the DCT treatment is attributed to the transformation of retained austenite into martensite. The microstructure is composed mainly of lath martensite; and the original grain size of the austenite can be appreciated. The choice of the combination: Hardness-toughness, is subject to the required service conditions of steel.Keywords: deep cryogenic treatment; aged precipitation; martensitic steels;, mechanical properties; martensitic steels, hardness, carbides precipitaion
Procedia PDF Downloads 74148 The Role of Disturbed Dry Afromontane Forest of Ethiopia for Biodiversity Conservation and Carbon Storage
Authors: Mindaye Teshome, Nesibu Yahya, Carlos Moreira Miquelino Eleto Torres, Pedro Manuel Villaa, Mehari Alebachew
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Arbagugu forest is one of the remnant dry Afromontane forests under severe anthropogenic disturbances in central Ethiopia. Despite this fact, up-to-date information is lacking about the status of the forest and its role in climate change mitigation. In this study, we evaluated the woody species composition, structure, biomass, and carbon stock in this forest. We employed a systematic random sampling design and established fifty-three sample plots (20 × 100 m) to collect the vegetation data. A total of 37 woody species belonging to 25 families were recorded. The density of seedlings, saplings, and matured trees were 1174, 101, and 84 stems ha-1, respectively. The total basal area of trees with DBH (diameter at breast height) ≥ 2 cm was 21.3 m2 ha-1. The characteristic trees of dry Afromontane Forest such as Podocarpus falcatus, Juniperus procera, and Olea europaea subsp. cuspidata exhibited a fair regeneration status. On the contrary, the least abundant species Lepidotrichilia volkensii, Canthium oligocarpum, Dovyalis verrucosa, Calpurnia aurea, and Maesa lanceolata exhibited good regeneration status. Some tree species such as Polyscias fulva, Schefflera abyssinica, Erythrina brucei, and Apodytes dimidiata lack regeneration. The total carbon stored in the forest ranged between 6.3 Mg C ha-1 and 835.6 Mg C ha-1. This value is equivalent to 639.6 Mg C ha-1. The forest had a very low number of woody species composition and diversity. The regeneration study also revealed that a significant number of tree species had unsatisfactory regeneration status. Besides, the forest had a lower carbon stock density compared with other dry Afromontane forests. This implies the urgent need for forest conservation and restoration activities by the local government, conservation practitioners, and other concerned bodies to maintain the forest and sustain the various ecosystem goods and services provided by the Arbagugu forest.Keywords: aboveground biomass, forest regeneration, climate change, biodiversity conservation, restoration
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