3,753 research outputs found
Analysis of Secondary Adhesion Wear Mechanism on Hard Machining of Titanium Aerospace Alloy
Titanium alloys are widely used in important manufacturing sectors such as the aerospace industry, internal components of motor or biomechanical components, for the development of functional prostheses. The relationship between mechanical properties and weight and its excellent biocompatibility have positioned this material among the most demanded for specific applications. However, it is necessary to consider the low machinability as a disadvantage in the titanium alloys features. This fact is especially due to the low thermal conductivity, producing significant increases in the temperature of the contact area during the machining process. In this aspect, one of the main objectives of strategic industries is focused on the improvement of the efficiency and the increase of the service life of the elements involved in the machining of this alloy. With the aim to understand the most relevant effects in the machinability of the Ti6Al4V alloy, an analysis is required of different variables of the machining process like tool wear evolution, based on secondary adhesion mechanisms, and the relation between surface roughness of the work-pieces with the cutting parameters. In this research work, a study on the machinability of Ti6Al4V titanium alloy has been performed. For that purpose, in a horizontal turning process, the influence of cutting tool wear effects has been evaluated on the surface finish of the machined element. As a result, parametric behavior models for average roughness (Ra) have been determined as a function of the machining parameters used
Factores familiares asociados a los Trastornos Alimentarios: una revisión
From a multifactorial perspective this study present a review about the family factors associated to eating disorders, considering theoretical and empirical contributions in national and international journals articles . The find of the research about the Eating Disorders and Family, indicate that the principal topics investigated are: family functioning, daughters and fathers relationships, stressful experiences, family psychopathology, attitudes and behaviors about weigh, eating and body image in the affected families. We conclude recognizing the heterogeneity of the families with Eating Disorders and the complex combination of family factors associated to eating psychopathology. More research is suggested about: family functioning in EDNOS patients, the father´s role, protective factors, coping stress, body image and family food
Loose ends: almost one in five human genes still have unresolved coding status
Seventeen years after the sequencing of the human genome, the human proteome is still under revision. One in eight of the 22 210 coding genes listed by the Ensembl/GENCODE, RefSeq and UniProtKB reference databases are annotated differently across the three sets. We have carried out an in-depth investigation on the 2764 genes classified as coding by one or more sets of manual curators and not coding by others. Data from large-scale genetic variation analyses suggests that most are not under protein-like purifying selection and so are unlikely to code for functional proteins. A further 1470 genes annotated as coding in all three reference sets have characteristics that are typical of non-coding genes or pseudogenes. These potential non-coding genes also appear to be undergoing neutral evolution and have considerably less supporting transcript and protein evidence than other coding genes. We believe that the three reference databases currently overestimate the number of human coding genes by at least 2000, complicating and adding noise to large-scale biomedical experiments. Determining which potential non-coding genes do not code for proteins is a difficult but vitally important task since the human reference proteome is a fundamental pillar of most basic research and supports almost all large-scale biomedical projects.National Institutes of Health [2 U41 HG007234 to I.J., L.M., J.M.R. and M.L.T., R01 HG004037 to I.J.]. Funding for open access charge: NIH [2 U41 HG007234].S
Porous clays heterostructures as supports of iron oxide for environmental catalysis
[EN] Porous Clays Heterostructures (PCH) from natural pillared clays (bentonite with a high proportion of montmorillonite) have been used as supports of iron oxide for two reactions of environmental interest: i) the elimination of toluene (a representative compound of one of the most toxic subsets of volatile organic compounds, aromatics) by total oxidation and ii) the selective oxidation of H2S to elemental sulfur. For both reactions these catalysts have resulted to be remarkably more efficient than similar catalysts prepared using conventional silica as a support. Thus, in the total oxidation of toluene it has been observed that the catalytic activity obtained using siliceous PCH is two orders of magnitude higher than that with conventional silica. The catalytic activity has shown to be dependant of the capacity of the support for dispersing iron oxide in a way that the higher the dispersion of iron oxide on the surface of the support, the higher is the activity. In the case of the selective oxidation of H2S to S both higher catalytic activity and higher selectivity to S have been observed using siliceous porous clays heterostructures than using conventional silica. Highly dispersed FeOx species have been shown as highly selective towards elemental sulfur whereas more aggregated FeOx species favour the formation of sulphur oxides decreasing the selectivity to S. Analyses of the surface by XPS have shown the predominance of sulfate species in the catalysts presenting low selectivity to elemental sulfur.The authors would like to acknowledge the DGICYT in Spain (CTQ2015-68951-C3-1-R, CTQ2015-68951-C3-3-R, CTQ2012-37925-C03-2, CTQ2012-37925-C03-3 and CTQ2012-37984-C02-01) and FEDER for financial support. We also thank the University of Valencia for funding (UV-INV-AE-16-484416) and SCSIE-UV for assistance.Sanchis Martinez, R.; Cecilia, J.; Soriano Rodríguez, MD.; Vazquez, I.; Dejoz, A.; López Nieto, JM.; Rodriguez-Castellon, E.... (2008). Porous clays heterostructures as supports of iron oxide for environmental catalysis. Chemical Engineering Journal. 334:1159-1168. https://doi.org/10.1016/j.cej.2017.11.060S1159116833
Genetic diversity of Bm86 sequences in Rhipicephalus (Boophilus) microplus ticks from Mexico: analysis of haplotype distribution patterns
Artículo científico derivado de Tesis doctoral de Saúl Gabriel Martínez ArzateBackground: Ticks are a problem for cattle production mainly in tropical and subtropical regions, because they generate great economic losses. Acaricides and vaccines have been used to try to keep tick populations under control. This has been proven difficult given the resistance to acaricides and vaccines observed in ticks. Resistance to protein rBm86-based vaccines has been associated with the genetic diversity of Bm86 among the ectoparasite’s populations. So far, neither genetic diversity, nor spatial distribution of circulating Bm86 haplotypes, have been studied within the Mexican territory. Here, we explored the genetic diversity of 125 Bm86 cDNA gene sequences from R. microplus from 10 endemic areas of Mexico by analyzing haplotype distribution patterns to help in understanding the population genetic structure of Mexican ticks. Results: Our results showed an average nucleotide identity among the Mexican isolates of 98.3%, ranging from 91.1 to 100%. Divergence between the Mexican and Yeerongpilly (the Bm86 reference vaccine antigen) sequences ranged from 3.1 to 7.4%. Based on the geographic distribution of Bm86 haplotypes in Mexico, our results suggest gene flow occurrence within different regions of the Mexican territory, and even the USA. Conclusions: The polymorphism of Bm86 found in the populations included in this study, could account for the poor efficacy of the current Bm86 antigen based commercial vaccine in many regions of Mexico. Our data may contribute towards designing new, highly-specific, Bm86 antigen vaccine candidates against R. microplus circulating in Mexico.SIEAE UAEM FES
Animal Models of Rheumatoid Arthritis
Autoimmunity is a condition in which the host organizes an immune response against its own antigens. Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology, characterized by the presence of chronic inflammatory infiltrates, the development of destructive arthropathy, bone erosion, and degradation of the articular cartilage and subchondral bone. There is currently no treatment that resolves the disease, only the use of palliatives, and not all patients respond to pharmacologic therapy. According to RA multifactorial origin, several in vivo models have been used to evaluate its pathophysiology as well as to identify the usefulness of biomarkers to predict, to diagnose, or to evaluate the prognosis of the disease. This chapter focuses on the most common in vivo models used for the study of RA, including those related with genetic, immunological, hormonal, and environmental interactions. Similarly, the potential of these models to understand RA pathogenesis and to test preventive and therapeutic strategies of autoimmune disorder is also highlighted. In conclusion, of all the animal models discussed, the CIA model could be considered the most successful by generating arthritis using type II collagen and adjuvants and evaluating therapeutic compounds both intra-articularly and systemically
West Nile virus emergence in humans in Extremadura, Spain 2020
In Spain, the largest human West Nile virus (WNV) outbreak among humans was reported in 2020, constituting the second most important outbreak in Europe that season. Extremadura (southwestern Spain) was one of the affected areas, reporting six human cases. The first autochthonous human case in Spain was reported in Extremadura in 2004, and no other human cases were reported until 2020. In this work, we describe the first WNV human outbreak registered in Extremadura, focusing on the most important clinical aspects, diagnostic results, and control actions which followed. In 2020, from September to October, human WNV infections were diagnosed using a combination of molecular and serological methods (an in-house specific qRT-PCR and a commercial ELISA for anti-WNV IgM and IgG antibodies) and by analysing serum, urine, and/or cerebrospinal fluid samples. Serological positive serum samples were further tested using commercial kits against related flaviviruses Usutu and Tick-borne encephalitis in order to analyse serological reactivity and to confirm the results by neutralisation assays. In total, six cases of WNV infection (five with neuroinvasive disease and one with fever) were identified. Clinical presentation and laboratory findings are described. No viral RNA was detected in any of the analysed samples, but serological cross-reactivity was detected against the other tested flaviviruses. Molecular and serological methods for WNV detection in various samples as well as differential diagnosis are recommended. The largest number of human cases of WNV infection ever registered in Extremadura, Spain, occurred in 2020 in areas where circulation of WNV and other flaviviruses has been previously reported in humans and animals. Therefore, it is necessary to enhance surveillance not only for the early detection and implementation of response measures for WNV but also for other emerging flaviviruses that could be endemic in this area.This research was partially funded by the project PI19CIII/00014 from the Instituto de Salud Carlos III.S
The incorporation of the SDGs in the Technical Architecture and Building plan (2021) of the University of Alcalá
[EN] The Bachelor's degrees of the first round of verifications (2008), have the
obligation to review and renew their teaching approaches, since neither the
ways of teaching, nor the ways of practicing the profession, nor the technologies
are the same in 2021. There is an opportunity to update the contents and the
interrelation between them. The Sustainable Development Goals (SDGs) can
and should be part of this process of teaching innovation. This is the case of
the evolution of the Degree in Science and Technology of Building, to the
Degree in Technical Architecture and Building, recently approved (March
2021). The objective of the communication is to present the method followed
for the integration of the SDGs in the verification process. The way practiced to
determine the goals of each SDG to be incorporated is analyzed. The
prioritization of the character of transversality in the planned approach, not as
a specific subject but integrated, coordinated, and related between the different
subjects in which it is progressively integrated into the degree. Finally, the
definitive incorporation procedure to the Plan, its documentary and conceptual
reflection, and the implementation forecast, the monitoring and control
processes for the 2021/2022 academic year will be discussed.[ES] Las titulaciones de Grado de la primera tanda de verificaciones (2008), tienen la obligación de revisar y renovar sus planteamientos docentes, ya que ni los modos de enseñar, ni los modos de ejercer la profesión, ni las tecnologías son las mismas en 2021. Se presenta una oportunidad de actualización de los contenidos y la interrelación entre ellos. Los Objetivos de Desarrollo Sostenible (ODS) pueden y deben formar parte de este proceso de innovación docente. Es el caso de la evolución del Grado en Ciencia y Tecnología de la Edificación, al Grado de Arquitectura Técnica y Edificación, aprobado recientemente (marzo 2021). El objetivo de la comunicación es presentar el método seguido para la integración de los ODS en el proceso de verificación. Se analiza el modo practicado para determinar las metas de cada ODS a incorporar. La priorización del carácter de transversalidad en el enfoque planificado, no como materia específica sino integrada, coordinada, y relacionada entre las diferentes asignaturas en las que se integra de forma progresiva en la titulación. Por último se comentará el procedimiento de incorporación definitiva al Plan, su reflejo documental y conceptual, y la previsión de implantación, los procesos de seguimientos y control para el curso 2021/2022.Da Casa Martín, F.; Baño Nieva, A.; Vega Ballesteros, JM.; Delgado Conde, I.; Maza Vazquez, F.; Fernandez Tapia, E.; Temiño Vela, J.... (2021). La incorporación de los ODS en el plan de estudios de Arquitectura Técnica y Edificación (2021) de la Universidad de Alcalá. En EDIFICATE. I Congreso de Escuelas de Edificación y Arquitectura Técnica de España. Editorial Universitat Politècnica de València. 409-421. https://doi.org/10.4995/EDIFICATE2021.2021.13543OCS40942
Hypothalamic AMPK-ER Stress-JNK1 Axis Mediates the Central Actions of Thyroid Hormones on Energy Balance
Thyroid hormones (THs) act in the brain to modulate energy balance. We show that central triiodothyronine (T3) regulates de novo lipogenesis in liver and lipid oxidation in brown adipose tissue (BAT) through the parasympathetic (PSNS) and sympathetic nervous system (SNS), respectively. Central T3 promotes hepatic lipogenesis with parallel stimulation of the thermogenic program in BAT. The action of T3 depends on AMP-activated protein kinase (AMPK)-induced regulation of two signaling pathways in the ventromedial nucleus of the hypothalamus (VMH): decreased ceramide-induced endoplasmic reticulum(ER) stress, which promotes BAT thermogenesis, and increased c-Jun N-terminal kinase (JNK) activation, which controls hepatic lipid metabolism. Of note, ablation of AMPK alpha 1 in steroidogenic factor 1 (SF1) neurons of the VMH fully recapitulated the effect of central T3, pointing to this population in mediating the effect of central THs on metabolism. Overall, these findings uncover the underlying pathways through which central T3 modulates peripheral metabolism.Peer reviewe
Surgical treatment for colorectal cancer: Analysis of the influence of an enhanced recovery programme on long-term oncological outcomes-a study protocol for a prospective, multicentre, observational cohort study
Introduction
The evidence currently available from enhanced recovery after surgery (ERAS) programmes concerns their benefits in the immediate postoperative period, but there is still very little evidence as to whether their correct implementation benefits patients in the long term. The working hypothesis here is that, due to the lower response to surgical aggression and lower rates of postoperative complications, ERAS protocols can reduce colorectal cancer-related mortality. The main objective of this study is to analyse the impact of an ERAS programme for colorectal cancer on 5-year survival. As secondary objectives, we propose to analyse the weight of each of the predefined items in the oncological results as well as the quality of life.
Methods and analysis
A multicentre prospective cohort study was conducted in patients older than 18 years of age who are scheduled to undergo surgery for colorectal cancer. The study involved 12 hospitals with an implemented enhanced recovery protocol according to the guidelines published by the Spanish National Health Service. The intervention group includes patients with a minimum implementation level of 70%, and the control group includes those who fail to reach this level. Compliance will be studied using 18 key performance indicators, and the results will be analysed using cancer survival indicators, including overall survival, cancer-specific survival and relapse-free survival. The time to recurrence, perioperative morbidity and mortality, hospital stay and quality of life will also be studied, the latter using the validated EuroQol Five questionnaire. The propensity index method will be used to create comparable treatment and control groups, and a multivariate regression will be used to study each variable. The Kaplan-Meier estimator will be used to estimate survival and the log-rank test to make comparisons. A p value of less than 0.05 (two-tailed) will be considered to be significant.
Ethics and dissemination
Ethical approval for this study was obtained from the Aragon Ethical Committee (C.P.-C.I. PI20/086) on 4 March 2020. The findings of this study will be submitted to peer-reviewed journals (BMJ Open, JAMA Surgery, Annals of Surgery, British Journal of Surgery). Abstracts will be submitted to relevant national and international meetings.
Trial registration number NCT04305314
- …