Incorporation of form deviations into the matrix transformation method for tolerance analysis in assemblies

Comunicación presentada a MESIC 2019 8th Manufacturing Engineering Society International Conference (Madrid, 19-21 de Junio de 2019)Mathematical models for tolerance representation are used to assess how the geometrical variation of a specific component feature propagates along the assembly, so that tolerance analysis in assemblies can be carried out using a specific tolerance propagation method. Several methods for tolerance analysis have been proposed in the literature, being some of them implemented in CAD systems. All these methods require modelling the geometrical variations of the component surfaces: parametric models, variational models, DoF models, etc. One of the most commonly used models is the DoF model, which is employed in a number of tolerance analysis methods: Small Displacement Torsor (SDT), Technologically and Topologically Related Surfaces (TTRS), Matrix Transformation, Unified Jacobian–Torsor model. However, none of the DoF-based tolerance analysis methods incorporates the effect of form deviations. Among the non DoF-based methods, there are two that include form tolerances: the Vector Loop or Kinematic method and the Tolerance Map (T-Map) model, although the latter is still under development. In this work, a proposal to incorporate form deviations into the matrix transformation method for tolerance analysis in assemblies is developed using a geometrical variation model based on the DoF model. The proposal is evaluated applying it to a 2D case study with components that only have flat surfaces, but the proposal can be extrapolated to 3D cases

Diseño de un Kit Modular para Mejorar el Aprendizaje de los Conceptos de Diseño para Ensamblaje (DFA)

Comunicación presentada al XXVII Congreso Universitario de Innovación Educativa en las Enseñanzas Técnicas (Alcoi, 17-19 Junio, 2019.)Students show significant difficulties when having to acquire and take in certain concepts present in some courses in the field of Manufacturing Engineering. Generally, theoretical concepts taught in class are supported by the use of visuals and graphic material. In addition, application cases are solved in practical sessions to complete the acquisition of related skills. However, it has been proved that a considerable amount of students still misunderstands some concepts and finds their application troublesome. In particular, this is the case of some concepts related to the application of Design for Assembly (DFA). In order to enhance the understanding of the concepts and the acquisition of the required skills for their right application, in this work, the design of several DFA modular kits to be experimentally used by students is proposed. The kits will allow students to practise with various product configurations, each of them including different functional inconsistencies. Product features will be modified by replacing portions of the same component (modular kits) rather than by using a large number of different components with the purpose of simplifying the process and illustrating the idea of modifying a component feature instead of replacing it.Los estudiantes presentan dificultades significativas en la adquisición y asimilación de ciertos conceptos presentes en algunas asignaturas del ámbito de la Ingeniería de Fabricación. Generalmente los conceptos teóricos explicados en clase se complementan con material gráfico. Además, la adquisición de las destrezas relacionadas se completa con la resolución de casos de aplicación en sesiones prácticas. Sin embargo, se ha comprobado que una cantidad considerable de estudiantes sigue mostrando dificultades en la compresión de algunos conceptos y encuentra su aplicación problemática. Este el caso de algunos conceptos relacionados con la aplicación del Diseño para Ensamblaje (Design for Assembly, DFA). Con el fin de mejorar la comprensión de los conceptos y la adquisición de las destrezas necesarias para su correcta aplicación, en este trabajo se propone el diseño de kit modular de DFA para ser usado por los estudiantes de forma experimental. Los kits permiten a los estudiantes practicar con varias configuraciones del producto, cada una de ellas con diferentes anomalías funcionales. Se modificarán algunos rasgos característicos del producto sustituyendo partes de un mismo componente (kits modulares) en lugar de utilizando un elevado número de componentes diferentes con el propósito de simplificar el proceso y de inculcar la idea de modificar un rasgo de un componente en lugar de sustituirlo

Development of a modular kit to improve DFA learning

Ponencia presentada en: 9th Manufacturing Engineering Society International Conference (MESIC 2021) 23-25 jun 2021, Gijόn,DFA (Design for assembly) is an important part of the contents included in some of the manufacturing courses taught at Jaume I University. DFA is a tool to analyse and improve product design from an assembly point of view. Although DFA contents had been covered using different teaching activities (theoretical, problem and laboratory sessions), the results in students’ assessment revealed that the expected learning outcomes were not being achieved. In particular, results were especially unsatisfactory in the practical application of DFA. Students misunderstood concepts such as “handling” and “insertion” operations, and failed at identifying assembly problems related to thickness or alignment among others. A learning by doing approach has been proved to improve students’ learning and engagement, as they take an active role and have the opportunity of doing things themselves. In a previous work, a specific modular and reconfigurable kit to improve DFA learning by experimentation was designed. Based on this work, this paper presents the analysis of the results obtained in two different courses where the modular kit has been used by students in a new seminar session

Oxidative stress status in an institutionalised elderly group after the intake of a phenolic-rich dessert

The present study was supported by a grant from Hero España S.A. M. C. R.-T. and J. L. Q. are recipients of a ‘Ramón y Cajal’ contract from the Ministry of Science and Technology and the University of Granada, Spain. We also thank the Fundacio´n Se´neca of the C.A.R.M. (Murcia, Spain) for the fellowship of J. G.-A.The elderly population undergoes a series of physiological and sociological changes common to old age with a high probability of suffering degenerative illness and malnutrition. A dessert rich in phenolic compounds has been designed by using concentrated juices of grape, cherry, blackberry, blackcurrant and raspberry with the aim of it being used as a complementary food in adulthood. In the present study, we investigated the effect of the intake of this dessert (a jar of 200 g daily for a period of 2 weeks), with an antioxidant activity equivalent to ten servings of fruits and vegetables, on several markers of oxidative and antioxidant status in DNA and plasma in a group of elderly individuals. Non-smoking institutionalised elderly subjects were recruited from a pool of volunteers in an old-age home in Murcia (Spain). Twenty-two subjects (six men and sixteen women) participated in the study. The study was designed as a randomised intervention trial with a period of 2 weeks. At days 1 and 15, blood samples were collected to analyse total antioxidant capacity, biochemical parameters, antioxidant vitamins, LDL peroxidation, and DNA damage in peripheral blood lymphocytes. The conclusion of the present study is that a 2-week intervention with our dessert enriched with natural polyphenol compounds in elderly individuals does not give enough time to find changes in the antioxidant and oxidative status. Also, the view that the marked antioxidant ability of polyphenols in vitro does not translate to analogous effects in vivo was confirmed. Moreover, a highly oxidative stress status during ageing was confirmed, together with the need to perform follow-up nutritional studies to improve this situation

Distribution of alien tetrapods in the Iberian Peninsula

We present a dataset that assembles occurrence records of alien tetrapods (amphibians, reptiles, birds and mammals) in the Iberian Peninsula, a coherent biogeographically unit where introductions of alien species have occurred for millennia. These data have important potential applications for ecological research and management, including the assessment of invasion risks, formulation of preventive and management plans, and research at the biological community level on alien species. This dataset summarizes inventories and data sources on the taxonomy and distribution of alien tetrapods in the Iberia Peninsula, comprising known locations from published literature, expert knowledge and citizen science platforms. An expert-based assessment process allowed the identification of unreliable records (misclassification or natural dispersion from native range), and the classification of species according to their status of reproduction in the wild. Distributional data was harmonized into a common area unit, the 10 × 10 km Universal Transverse Mercator (UTM) system (n = 6,152 cells). The year of observation and/or year of publication were also assigned to the records. In total, we assembled 35,940 unique distribution records (UTM × species × Year) for 253 species (6 amphibians, 16 reptiles, 218 birds and 13 mammals), spanning between 1912 and 2020. The species with highest number of distribution records were the Mediterranean painted frog Discoglossus pictus (n = 59 UTM), the pond slider Trachemys scripta (n = 471), the common waxbill Estrilda astrild (n = 1,275) and the house mouse Mus musculus (n = 4,043), for amphibians, reptiles, birds and mammals, respectively. Most alien species recorded are native to Africa (33%), followed by South America (21%), Asia (19%), North America (12%) and Oceania (10%). Thirty-six species are classified by IUCN as threatened in their native range, namely 2 Critically Endangered (CR), 6 Endangered (EN), 8 Vulnerable (VU), and 20 species Near Threatened (NT). Species maps are provided in DataSet1, as well R code and GIS layers to update them as new records are obtained.info:eu-repo/semantics/publishedVersio

Assessing the congruence of thermal niche estimations derived from distribution and physiological data. A test using diving beetles.

A basic aim of ecology is to understand the determinants of organismal distribution, the niche concept and species distribution models providing key frameworks to approach the problem. As temperature is one of the most important factors affecting species distribution, the estimation of thermal limits is crucially important for inferring range constraints. It is expectable that thermal physiology data derived from laboratory experiments and species' occurrences may express different aspects of the species' niche. However, there is no study systematically testing this prediction in a given taxonomic group while controlling by potential phylogenetic inertia. We estimate the thermal niches of twelve Palaearctic diving beetles species using physiological data derived from experimental analyses in order to examine the extent to which these coincided with those estimated from distribution models based on observed occurrences. We found that thermal niche estimates derived from both approaches lack general congruence, and these results were similar before and after controlling by phylogeny. The congruence between potential distributions obtained from the two different procedures was also explored, and we found again that the percentage of agreement were not very high (~60%). We confirm that both thermal niche estimates derived from geographical and physiological data are likely to misrepresent the true range of climatic variation that these diving beetles are able to tolerate, and so these procedures could be considered as incomplete but complementary estimations of an inaccessible reality

Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Incorporating phylogeographic information in alien bird distribution models increases geographic extent but not accuracy of predictions

Species distribution models (SDM) have been proposed as valuable first screening tools for predicting species responses to new environmental conditions. SDMs are usually conducted at the species level, assuming that species-environment relationships are a species-specific feature that do not evolve and show no variability across a species' range. However, broad environmental tolerances at the species level can encompass narrower and different environmental tolerances for specific lineages or populations. In this study, we evaluate whether SDMs that account for within-taxon niche variation in climate and human-habitat associations provide better fits between projected distributions and real occurrence data for alien bird species than species-level SDMs. Our study focuses on eight alien bird species with established alien populations for which detailed phylogeographic information was available. Similarity in climates and human disturbance conditions occupied by different phylogenetic groups within species was low and not greater than random expectations. Accounting for intraspecific niche variation in SDMs modified the distribution and extent of suitable habitat predicted as susceptible to invasion, but did not result in more accurate model predictions in alien ranges. Until more accurate information on intraspecific variability is available, species-level models can be reasonable candidates. When phylogeographic information is available, the use of the most conservative criterion (i.e. to model both species and lineages on the basis of the actual range) is recommended