Single-particle cryo-electron microscopy studies of ribosomes with fragmented 28S rRNA

In the past five years, single-particle cryo-electron microscopy (cryo-EM) has revolutionized structural biology. Recent advances in detector technology and powerful computational methods now allow images of unprecedented detail to be recorded and structures to be determined at near-atomic resolution. For my PhD studies, I took advantage of this technique to study the structure of uniquely fragmented ribosomes. Ribosomes, are large macromolecular complexes that translate genetic information carried by messenger RNAs (mRNAs) into polypeptide chains. They are the protein production factories of all living cells and are thus involved in virtually all aspects of cellular development and maintenance. By virtue of their core role in the cell, ribosomes share a highly evolutionarily conserved core that carries out the fundamental processes of protein synthesis [1]. However, outside of this core, ribosome composition varies considerably. The main differences among eukaryotic ribosomes are due to rRNA expansion segments (ESs) and variations of ribosomal proteins (r-proteins) [1, 2]. Further, rRNA fragmentation occurring in regions of high variability has been reported in several organisms from bacteria to protozoa, insects, helminths, fish, and surprisingly mammals [3-15]. Recently, the naked mole-rat (Heterocephalus glaber) was discovered to have unusual cleavage sites in its 28S rRNA resulting in the deletion of the major part of the D6 variable region (ES15L) and leaving the two rRNA fragments disconnected [14]. The cleaved 28S rRNA has been associated with the naked mole rat’s increased translational fidelity [14]. The only other known mammals having fragmented rRNA are the tuco-tuco rodent (of the genus Ctenomys) and the degu (in the related genus Octodontomys) [13]. Here we present the high-resolution structures of the naked mole-rat, tuco-tuco, and guinea pig (Cavia porcellus) ribosomes. Guinea pig, which has canonical (non-fragmented) 28S rRNA is used as a rodent model for comparisons to the naked mole-rat and tuco-tuco ribosomes. During my PhD studies, I also looked at another uniquely fragmented ribosome, that of the protozoan parasite, Trypanosoma cruzi (T. cruzi), the causative agent of Chagas disease. The T. cruzi large subunit (LSU) rRNA is assembled from 8 pieces-5S, 5.8S, and six pieces forming jointly the 28S rRNA. Together with my colleagues from Joachim Frank’s and Liang Tong’s research groups, we solved the structure of the T. Cruzi LSU and identified distinctive trypanosome interactions, which allowed us to propose a tentative model for assembly of the large ribosomal subunit (60S) [16, 17]

Centro recreativo y habitacional: una aproximación sensorial

One of the principal themes discussed in this text is related to the psychology of perception in architecture. There is also an architectural project which has been developed with this text and it has a program related to housing and to entertainment. Architecture itself provokes multiple “sensorial experiences” in human beings. As a consequence, the project mentioned above is going to be able to exalt the senses because of the usage of color, texture, etc. These elements are essential during the process of perception. Consequently, people are going to be able to experience these architectural spaces in a specific way. This “experience of architecture” is going to be unique in every human being.En esta tesis se desarrollan varios temas relacionados a la psicología de la percepción en el campo de la arquitectura. El proyecto a desarrollarse conjuntamente cuenta con espacios destinados tanto a actividades de recreación como habitacionales. La ubicación de este se da en un punto estratégico dentro de la ciudad de Quito cerca a la Avenida República del Salvador (lote del Colegio Benalcázar). Se propone crear una multiplicidad de espacios que provoquen varios tipos de “experiencias” arquitectónicas. Edificaciones en donde la textura, el color, etc. serán elementos esenciales ya que nadie podrá vivir o percibir lo que otro ser humano; todo esto debido a que cada uno percibe de manera individual la arquitectura

Signalling Three-Way Intersections: Is Redundancy Better Than Only Mandatory or Prohibitory Signs?

This work was supported by the Spanish Government, Ministry of Economy and Competitiveness (PGC2018-095868-B-I00).At intersections, drivers need to infer which ways are allowed by interpreting mandatory and/or prohibitory traffic signs. Time and accuracy in this decision-making process are crucial factors to avoid accidents. Previous studies show that integrating information from prohibitory signs is generally more difficult than from mandatory signs. In Study 1, we compare combined redundant signalling conditions to simple sign conditions at three-way intersections. In Study 2, we carried out a survey among professionals responsible for signposting to test whether common practices are consistent with experimental research. In Study 1, an experimental task was applied (n = 24), and in Study 2, the survey response rate was 17%. These included the main cities in Spain such as Madrid and Barcelona. Study 1 showed that inferences with mandatory signs are faster than those with prohibitory signs, and redundant information is an improvement only on prohibitory signs. In Study 2, prohibitory signs were those most frequently chosen by professionals responsible for signposting. In conclusion, the most used signs, according to the laboratory study, were not the best ones for signposting because the faster responses were obtained for mandatory signs, and in second place for redundant signs.Spanish Government, Ministry of Economy and Competitiveness PGC2018-095868-B-I0

Studying upper-limb kinematics using inertial sensors

AIM: The aim of this study was to analyze scapulohumeral rhythm through nine physical properties that correspond to angular mobility, angular velocity, and acceleration in the three axes of space, obtained by inertial sensors. METHODS: This cross-sectional study recruited healthy young adult subjects. Descriptive and anthropometric independent variables related to age, gender, weight, size, and BMI were included. Nine physical properties were included corresponding to three dependent variables for each of three special axes: mobility angle (degrees), angular speed (degrees/second), and lineal acceleration (meters/seconds2), which were obtained thought the inertial measurement sensors with four inertial sensors (InertiaCube3™ Intersense Inc., Billerica, Massachusetts). Inertial sensors were placed in the right half of the body of each subject located in the middle third of the humerus slightly posterior, in the middle third of the upper spine of the scapula, in the flat part of the sternum, and the distal surface of the ulna and radius. RESULTS: Descriptive graphics of analytical tasks performed were obtained (figure 1). The main difference in mobility between the scapula and humerus was found in pitch axis for abduction ( = 107.6°, SD = 9.3°) and flexion ( = 113.1°, SD = 9.3°). CONCLUSION: This study shows how much each body segment contributes to upper-limb motion, and allows us to obtain grades of mobility provided by the scapula. Also, this study identified movement patterns, and supports inertial sensors as a useful device to analyze upper-limb kinematics. However, further studies with subjects with shoulder pathology should be carried out.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Transporte en animales de compañía

Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223

Experimental and theoretical study of the thermal decomposition of ethyl acetate during fast pyrolysis

The thermal decomposition of ethyl acetate was experimentally studied in a newly designed fast pyrolysis set-up. The results were compared to theoretical calculations and literature values in order to proof the experimental concept. The reaction was carried out in a free fall tubular reactor with a residence time of 0.15 s. The identification and quantification of products stream composition was performed online using a GC-TCD/FID. First, an overview of the reaction rate at feed volumes of 0.25, 0.50 and 0.75 mL was obtained at reaction temperature between 400 to 600 degrees C in intervals of 50 degrees C. As a result mass transfer limitation for feeds larger than 0.5 mL were identified. For the second approach, a constant feed volume of 0.25 mL and temperatures between 420 to 550 degrees C were investigated. Using the experimental results, a global kinetic model is proposed for the thermal decomposition of ethyl acetate into ethylene and acetic acid through a first order unimolecular reaction. Also, theoretical calculations were performed at wB97XD/6-311++G(d,p) level. A concerted mechanism through a six-membered transition state was identified in the reaction path. The theoretical and experimental activation energy values lie within the literature values between 193 and 213 kJ/mol. 2020 The Authors. Published by Elsevier B.V. on behalf of Institution of Chemical Engineers. This is an open access article under the CC BY-NC -ND license (http://creativecommons.orgilicenseseby-nc-nd/450/)

Clean Label in Bread

Bread is considered a staple food worldwide, and therefore there is much interest in research around the topic. The bread industry is usually looking for ways to improve its formulations. Therefore, other ingredients such as dough conditioners, crumb softeners, emulsifiers, and surfactants can be added to enhance bread quality. These ingredients perform functions such as helping standardize processes in the industry, reducing dough-mixing time, increasing water absorption, improving bread quality, and extending its shelf life. Consumers are concerned about the effect of these ingredients on their health, and this has increased the popularity of clean-label bread formulations. A clean label generally indicates that a product is free of chemical additives, has an ingredient list that is easy to understand, has undergone natural or limited processing, and/or is organic and free of additives or preservatives. However, there is no scientific definition of the term “clean label.” Researchers have focused on these clean-label initiatives to replace dough strengtheners and preservatives in bread formulations and give consumers what they perceive as a healthier produc

Propuesta de nuevas prácticas para el laboratorio de máquinas eléctricas del programa de tecnología eléctrica

El presente trabajo de grado desarrolla tres tipos de prácticas para ser realizadas en el laboratorio de máquinas eléctricas del curso TE5E2 con el fin de que sean involucradas como guías en el programa académico del curso. Las prácticas propuestas son: tipos de arranques, frenados y eficiencia de las máquinas eléctricas. Para la realización de las guías de laboratorio se revisaron las guías actuales del Laboratorio de Máquinas eléctricas del programa de tecnología eléctrica y se realizó un inventario de los elementos disponibles para realizar un plan de trabajo consecuente con los objetivos del curso y aprovechando los materiales que actualmente existen en el almacén. También se realizó la búsqueda de toda la información necesaria para comenzar a realizar las pruebas, tal que se pudiera tener claro el tipo de conexión y análisis que se debía tener con cada una de las prácticas a ejecutar. Además, todas las pruebas se realizaron en el laboratorio de máquinas eléctricas con el software de LabVolt, el cual permitió obtener la mayoría de datos, los cuales son mostrados en este documento. Por último, al final del documento se entregan como anexos, una propuesta de cómo deberían estar planteadas las guías en caso de ser anexadas al plan de estudios de la asignatura