King Juan Carlos University
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Morphological and molecular characterization of Xiphinemella esseri Chitwood,1957 (Dorylaimida: Leptonchidae) from Florida, with the first molecular study of the genus
No full textA population of Xiphinemella esseri, recently collected under the canopy of associated live oak trees in north Florida, was studied and described with an integrative approach, including the first molecular study of the genus. This Florida population is characterized by its 2.30 to 3.32 mm long body, labial disc well developed, lip region offset by constriction, and 16.5 to 17.5 mu m broad, odontostyle 46 to 49 mu m long with minute aperture, neck 288 to 296 mu m long, pharyngeal expansion occupying 28 to 30% of total neck length, uterus a tripartite tube-like structure, pars refringens vaginae absent, vulva transverse (V = 45.4-49.7%), tail short and rounded (18-28 mu m, c = 94-158, c' = 0.6-0.9), spicules 41 to 45 mu m long, and 8 to 10 irregularly spaced ventromedian supplements bearing hiatus. The phylogenetic analysis inferred from the D2-D3 expansion segments of 28S rRNA gene and 18S rRNA gene sequences showed that X. esseri clustered with other dorylaims from the family Leptonchidae. A brief discussion about the distribution and biological considerations of X. esseri is also provided
Designing interactive, gamified learning environments: a methodological approach with a case study on statistical quality control
No full textStatistical Quality Control is a subject present in many engineering degrees. Literature identifies shortcomings in the application of Statistical Quality Control in industry. Some factors include a lack of training, misunderstandings or failures in implementing Statistical Quality Control. Many authors suggest following new methodologies (e.g. Problem-Based Learning) to improve the teaching of Statistical Quality Control, but, in general, universities continue applying the traditional methodology based on master classes. In this paper, we propose a methodology to design interactive gamified environments, and apply it to improve the Statistical Quality Control teaching-learning process. This methodology is based on two phases. The first one focuses on the design of the formative itinerary. For this, taking into account the competencies and learning objectives, the teacher applies a divide-and-conquer approach to break down the content into concepts, elaborates a graph of dependencies (which reflects the dependencies between the concepts, their complexity and the required cognitive level) and designs the formative itinerary to define the order in which the individual modules will be presented, together with a strategy of controlled content exposure. This process generates a stable structure that will support the second phase, consisting of selecting diverse learning activities for each module to promote active, self-paced, reflective, and engaged learning. We apply this methodology by dividing the Statistical Quality Control content into modules that comprise the key concepts, creating a formative itinerary. Given that structure, for each module, we select learning activities that encourage active learning and we translate it all into a game-like tool. This tool not only includes gamification elements like scoreboards, stars, and a map, but it further innovates by including as learning activities interactive serious games that help to visualize and understand the Statistical Quality Control process, by performing real-life tasks, resulting in significant learning. It also incorporates other educational strategies to promote active learning, such as flipped classroom and the inclusion of formative assessment. The content exposure control is implemented through tests on quality control to ensure students’ assimilation of the concepts before allowing them to move on to activities or problems that require higher cognitive levels. We evaluate the methodology’s effectiveness through an experiment that shows that students who used the learning tool improved their knowledge (p-value < 0.001) in comparison to their peers who only attended a traditional master class. Students also thought that this type of application is a good complementary material for the course and that it helps to improve knowledge assimilation (score of 4.94 out of 5 points)
Automatic Personality Assessment through Movement Analysis
No full textObtaining accurate and objective assessments of an individual's personality is vital in many areas including education, medicine, sports and management. Currently, most personality assessments are conducted using scales and questionnaires. Unfortunately, it has been observed that both scales and questionnaires present various drawbacks. Their limitations include the lack of veracity in the answers, limitations in the number of times they can be administered, or cultural biases. To solve these problems, several articles have been published in recent years proposing the use of movements that participants make during their evaluation as personality predictors. In this work, a multiple linear regression model was developed to assess the examinee's personality based on their movements. Movements were captured with the low-cost Microsoft Kinect camera, which facilitates its acceptance and implementation. To evaluate the performance of the proposed system, a pilot study was conducted aimed at assessing the personality traits defined by the Big-Five Personality Model. It was observed that the traits that best fit the model are Extroversion and Conscientiousness. In addition, several patterns that characterize the five personality traits were identified. These results show that it is feasible to assess an individual's personality through his or her movements and open up pathways for several research
Improving the Discriminability of Haptic Icons: The Haptic Tuning Fork
No full textTechnological advances enable the capture and management of complex data sets that need to be correctly understood. Visualisation techniques can help in complex data analysis and exploration, but sometimes the visual channel is not enough, or it is not always available. Some authors propose using the haptic channel to reinforce or substitute the visual sense, but the limited human haptic short-term memory still poses a challenge. We present the haptic tuning fork, a reference signal displayed before the haptic information for increasing the discriminability of haptic icons. With this reference, the user does not depend only on short-term memory. We have decided to evaluate the usefulness of the haptic tuning fork in impedance kinesthetic devices as these are the most common. Furthermore, since the renderable signal ranges are device-dependent, we introduce a methodology to select a discriminable set of signals called the haptic scale. Both the haptic tuning fork and the haptic scale proved their usefulness in the performed experiments regarding haptic stimuli varying in frequency
The Impact of Social Media on Gen Z’s Mental Health and Privacy
No full textOver the last decade, the ever-growing increase in social media usage among Generation Z has significantly influenced their behavior and mental health. In this context, the present study investigates the relationship among extensive social media use, psychological disorders, and privacy concerns in this generation. Using a structural equation model (PLS-SEM), we examine the relationships variables such as information overload, online reputation, social media fatigue, psychological disorders, and privacy concerns. One of our key findings is a positive correlation between information overload and social media fatigue, which highlight the cognitive burden of excessive digital information. Interestingly, our results do not show that open researchability significantly contributes to social media fatigue, suggesting effective information management by users. Furthermore, we find that addictive flow and online self-reputation concerns are positively associated with social media fatigue, suggesting that intense engagement and image management can be exhausting. This fatigue significantly escalates into psychological disorders, underlining the profound mental health implications of social media use. Moreover, the impact of psychological disorders and privacy concerns on the reduced intention to use social media observed in the data highlights a growing self-awareness and regulatory behavior among Generation Z. Collectively, the results of the present study offer meaningful insights for mental health professionals and social media platform designers, emphasizing the need for healthier online environments and strategies to promote digital well-being
Law enforcement agents at European borders: perceptions of migration, and the networked and relational exercise of discretion in policy implementation
No full textLaw enforcement agents (LEAs) operating at the forefront of European borders play a crucial role in the implementation of migration policies. As frontline actors, LEAs are often perceived as powerful agents who enforce legislation and determine who is granted entry or denied access to European territory. This study, conducted within the framework of the PERCEPTIONS project, examines LEAs' perceptions of migration and their discretionary implementation practices in five European countries. Our findings challenge the assumption that LEAs perceptions of migration are key in explaining their practices as they exercise discretionary power in an unlimited or unilateral manner. Instead, we argue that LEAs' daily practices are shaped through interactions within a complex network of actors. Adopting a networked and relational approach to discretion, this study highlights how power relations, negotiation, and inter-agency dynamics influence border enforcement, ultimately demonstrating that discretion is co-produced
Use of a microbial toxicity test (Microtox®) to determine the toxigenicity of Aspergillus fumigatus strains isolated from different sources
No full textThe toxic activity of Aspergillus fumigatus is attributable to substances secreted by its cells. Specific toxic compounds synthesized by the fungi such as gliotoxin, can be detected by sensitive chemical procedures like TLC or HPLC. Measuring the total toxigenicity of a strain extract, however, requires a bioassay. In the present study, we evaluated the possibility of using the Microtox (R) bioassay to determine the toxigenicity of A.fumigatus, using 32 strains from different sources. The Microtox (R) method is based on the ability of Vibrio fischeri to produce luminescence, and their sensitivity to toxins. A. fumigatus strains, grouped according to their original sources, showed differences in toxigenicity. Strains isolated from invasive aspergillosis patients proved to be more toxigenic than environmental strains, or strains from colonized patients. Since the strains that were more toxigenic were isolated from sick patients, it is not surprising they showed more virulence than the other strains, and as expected, virulence could be correlated with high toxigenicity. The Microtox bioassay could be a useful tool in the study of toxigenicity of the mycelial fungi and their possible pathogenic roles, and for rapid assessment of secreted toxic compounds. (C) 2009 Elsevier Ltd. All rights reserved
Aspectos sobre las finanzas descentralizadas DEFI, protocolo de préstamos
No full textEl artículo describe Defi, sistema de finanzas que se desarrolla a partir de 2017 en las denominadas permissioned blockchains, que implementa el modelo descentralizado. El movimiento de las denominadas Finanzas descentralizadas, permite a los usuarios utilizar servicios financieros y realizar operaciones sin la necesidad de depender de entidades centralizadas. DeFi puede comprender una prestación de servicios financieros por parte de múltiples participantes, intermediarios y usuarios finales en varias jurisdicciones, con una infraestructura puramente tecnológica para facilitar las interacciones entre diferentes agentes. El juego de las criptomonedas da paso a las aplicaciones descentralizadas y al ecosistema DeFi. Los préstamos son una de las categorías de protocolo señaladas en el marco de las finanzas descentralizadas. Crea instrumentos que permiten organizar el Mercado de préstamos y el más conocido es el generado por las bóvedas de Maker Dao. El DAI que se crea en la bóveda de MakerDAO como un criptoactivo estable. Describimos el sistema y aportamos las ultimas advertencias que señalar ser la descentralización de Defi una «ilusión» debido a que la necesidad de gobernanza hace inevitable cierto nivel de centralización y los aspectos estructurales del sistema conducen a una concentración de poder. Las actuales vulnerabilidades podrían llevar a socavar la estabilidad financiera si la expansión del sistema se generalizar