67 research outputs found

    Thin-Wall Machining of Light Alloys: A Review of Models and Industrial Approaches

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    Thin-wall parts are common in the aeronautical sector. However, their machining presents serious challenges such as vibrations and part deflections. To deal with these challenges, di erent approaches have been followed in recent years. This work presents the state of the art of thin-wall light-alloy machining, analyzing the problems related to each type of thin-wall parts, exposing the causes of both instability and deformation through analytical models, summarizing the computational techniques used, and presenting the solutions proposed by di erent authors from an industrial point of view. Finally, some further research lines are proposed

    Void Content Minimization in Vacuum Infusion (VI) via Effective Degassing

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    This paper addresses the major concern which component porosity represents in Vacuum Infusion (VI) manufacturing due to resin gelation at pressures close to absolute vacuum. Degassing is a fundamental step to minimize or even avoid resin outgassing and enhance dissolution of voids created during preform impregnation. The efficacy of different degassing procedures based on vacuum degassing, and assisted by adding a nucleation medium, High Speed (HS) resin stirring and/or later pressurization during different time intervals have been analyzed in terms of final void content is studied. Through a rigorous and careful design of the manufacturing process, outgassing effects on final void content were isolated from the rest of porosity causes and specimens with two clearly identifiable regions in terms of porosity were manufactured to facilitate its analysis. Maximum void content was kept under 4% and porous area size was reduced by 72% with respect to conventional vacuum degassing when resin was stirred at HS; therefore, highlighting the importance of enhancing bubble formation during degassing

    TGF-ÎČ antagonist attenuates fibrosis but not luminal narrowing in experimental tracheal stenosis.

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    Introduction/Objective: Acquired tracheal stenosis (ATS) is an unusual disease often secondary to prolonged mechanical trauma. ATS pathogenesis involves inflammation and subsequent fibrosis with narrowing of the tracheal lumen. TGF-ÎČ represents a pivotal factor in most fibrotic processes and therefore, a potential target in this context. The aim of this study is to analyze the role of TGF-ÎČ as a target for anti-fibrotic interventions in tracheal stenosis. Methods: Human stenotic tracheobronchial tissues from patients with benign airway stenosis and normal controls from pneumonectomy specimens were analyzed. Tracheal stenosis was induced in adult NZ rabbits by a circumferential thermal injury to the mucosa during open surgery and re-anastomosis. Rabbits were treated postoperatively with a peritracheal collagen sponge containing a TGF-ÎČ peptide antagonist (p17) or vehicle. Fibrosis was determined by Masson’s trichrome staining, and α-SMA+ Results: Human and rabbit stenotic tissues showed extensive submucosal fibrosis, characterized by significantly increased α-SMA myofibroblasts, CTGF and p-Smad2/3 expression by immunohistochemistry. + myofibroblasts and CTGF expression. In human stenotic lesions, increased p-Smad2/3+ nuclei were also observed. p17 treatment significantly reduced the fibrotic thickness as well as the density of α-SMA+ myofibroblasts and CTGF+ Conclusion: ATS is characterized by a TGF-ÎČ dependent fibrotic process but reduction of the fibrotic component by TGF-ÎČ1 antagonist therapy was not sufficient to improve tracheal narrowing, suggesting that fibrosis may not be the main contributor to luminal stenosis. cells in rabbit stenotic lesions but failed to improve the luminal area.pre-print1304 K

    Cistinosis en pacientes adolescentes y adultos: Recomendaciones para la atenciĂłn integral de la cistinosis

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    ResumenIntroducciĂłnLa cistinosis es una enfermedad lisosomal minoritaria de expresiĂłn sistĂ©mica con especial afectaciĂłn renal y oftalmolĂłgica, en la que los pacientes inician terapia renal sustitutiva en la primera dĂ©cada de la vida en ausencia de tratamiento. El pronĂłstico de la cistinosis depende del diagnĂłstico precoz, la pronta instauraciĂłn del tratamiento con cisteamina y el buen cumplimiento terapĂ©utico. La progresiĂłn de la enfermedad renal y de las complicaciones extrarrenales y una menor supervivencia, son mĂĄs acentuadas en pacientes no adherentes.ObjetivoEl objetivo de este trabajo fue la elaboraciĂłn de unas recomendaciones para la atenciĂłn integral de la cistinosis y la transiciĂłn del adolescente a la medicina del adulto, basadas en la experiencia clĂ­nica, con el fin de reducir el impacto de la enfermedad y mejorar la calidad de vida y el pronĂłstico del paciente.MĂ©todoBĂșsqueda bibliogrĂĄfica y reuniones de consenso de un equipo multidisciplinar de expertos en la prĂĄctica clĂ­nica con pacientes afectos de cistinosis (Grupo T-CiS.bcn), procedentes de 5 hospitales localizados en Barcelona.ResultadosEl documento recoge recomendaciones especĂ­ficas y necesarias para el diagnĂłstico, tratamiento y seguimiento multidisciplinar de la cistinosis en las siguientes ĂĄreas: nefrologĂ­a, diĂĄlisis, trasplante renal, oftalmologĂ­a, endocrinologĂ­a, neurologĂ­a, laboratorio, consejo genĂ©tico, enfermerĂ­a y farmacia.ConclusionesDisponer de un documento de referencia para la atenciĂłn integral de la cistinosis constituye una herramienta de soporte para los profesionales de la salud que asisten a estos pacientes. Los principales pilares en los que se sustenta son: a) el enfoque multidisciplinar, b) la adecuada monitorizaciĂłn de la enfermedad y control de los niveles de cistina intraleucocitarios, c) la importancia de la adherencia al tratamiento con cisteamina y d) la promociĂłn del autocuidado del paciente mediante programas de educaciĂłn en la enfermedad. Todo ello conducirĂĄ, en una segunda fase, a la elaboraciĂłn de un modelo de transiciĂłn coordinado entre los servicios de pediatrĂ­a y de adultos que contemple las necesidades especĂ­ficas de la cistinosis.AbstractIntroductionCystinosis is a rare lysosomal systemic disease that mainly affects the kidney and the eye. Patients with cystinosis begin renal replacement therapy during the first decade of life in absence of treatment. Prognosis of cystinosis depends on early diagnosis, and prompt starting and good compliance with cysteamine treatment. Kidney disease progression, extra-renal complications and shorter life expectancy are more pronounced in those patients that do not follow treatment.The objective of this work was to elaborate recommendations for the comprehensive care of cystinosis and the facilitation of patient transition from paediatric to adult treatment, based on clinical experience. The goal is to reduce the impact of the disease, and to improve patient quality of life and prognosis.MethodsBibliographic research and consensus meetings among a multidisciplinary professional team of experts in the clinical practice, with cystinotic patients (T-CiS.bcn group) from 5 hospitals located in Barcelona.ResultsThis document gathers specific recommendations for diagnosis, treatment and multidisciplinary follow-up of cystinotic patients in the following areas: nephrology, dialysis, renal transplant, ophthalmology, endocrinology, neurology, laboratory, genetic counselling, nursing and pharmacy.ConclusionsA reference document for the comprehensive care of cystinosis represents a support tool for health professionals who take care of these patients. It is based on the following main pillars: a) a multi-disciplinary approach, b) appropriate disease monitoring and control of intracellular cystine levels in leukocytes, c) the importance of adherence to treatment with cysteamine, and d) the promotion of patient self-care by means of disease education programmes. All these recommendations will lead us, in a second phase, to create a coordinated transition model between paediatric and adult care services which will cover the specific needs of cystinosis

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

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    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

    Influence of early neurological complications on clinical outcome following lung transplant

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    Sistema NerviĂłs AutĂČnom; Risc de malalties cardiovasculars; Procediments mĂšdics quirĂșrgics i invasiusSistema nervioso autĂłnomo; Riesgo de enfermedad cardiovascular; Procedimientos mĂ©dicos quirĂșrgicos e invasivosAutonomic Nervous System; Cardiovascular disease risk; Surgical and invasive medical proceduresBackground Neurological complications after lung transplantation are common. The full spectrum of neurological complications and their impact on clinical outcomes has not been extensively studied. Methods We investigated the neurological incidence of complications, categorized according to whether they affected the central, peripheral or autonomic nervous systems, in a series of 109 patients undergoing lung transplantation at our center between January 1 2013 and December 31 2014. Results Fifty-one patients (46.8%) presented at least one neurological complication. Critical illness polyneuropathy-myopathy (31 cases) and phrenic nerve injury (26 cases) were the two most prevalent complications. These two neuromuscular complications lengthened hospital stays by a median period of 35.5 and 32.5 days respectively. However, neurological complications did not affect patients’ survival. Conclusions The real incidence of neurological complications among lung transplant recipients is probably underestimated. They usually appear in the first two months after surgery. Despite not affecting mortality, they do affect the mean length of hospital stay, and especially the time spent in the Intensive Care Unit. We found no risk factor for neurological complications except for long operating times, ischemic time and need for transfusion. It is necessary to develop programs for the prevention and early recognition of these complications, and the prevention of their precipitant and risk factors.JG is the recipient of a grant from the Spanish Fondo de Investigaciones Sanitarias (FIS PI13-01272-FEDER)

    PTRF/Cavin-1 and MIF Proteins Are Identified as Non-Small Cell Lung Cancer Biomarkers by Label-Free Proteomics

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    With the completion of the human genome sequence, biomedical sciences have entered in the “omics” era, mainly due to high-throughput genomics techniques and the recent application of mass spectrometry to proteomics analyses. However, there is still a time lag between these technological advances and their application in the clinical setting. Our work is designed to build bridges between high-performance proteomics and clinical routine. Protein extracts were obtained from fresh frozen normal lung and non-small cell lung cancer samples. We applied a phosphopeptide enrichment followed by LC-MS/MS. Subsequent label-free quantification and bioinformatics analyses were performed. We assessed protein patterns on these samples, showing dozens of differential markers between normal and tumor tissue. Gene ontology and interactome analyses identified signaling pathways altered on tumor tissue. We have identified two proteins, PTRF/cavin-1 and MIF, which are differentially expressed between normal lung and non-small cell lung cancer. These potential biomarkers were validated using western blot and immunohistochemistry. The application of discovery-based proteomics analyses in clinical samples allowed us to identify new potential biomarkers and therapeutic targets in non-small cell lung cancer

    Fragmentos: leer, traducir, dialogar.

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    Pensar la enseñanza de la filosofía implica pensar tanto la noción de enseñanza como la concepción de filosofía. Mås que en una natural secuencia o linea conjunción, esta conversación que llamamos libro, se nutre de la relación compleja que va desde la enseñanza a la filosofía pero, también, desde la filosofía a la enseñanza. Es la actualización de una invitación ya anticipada por Alejandro Cerletti en relación a pensar la enseñanza desde la filosofía, es decir, como un problema filosófico; e, igualmente, es la actualización de otra invitación, aquella consistente en pensar la filosofía desde la enseñanza, esto es, como un problema pedagógico, como pråctica de formación, como ejercicio psicagógico. Siguiendo fines procedimentales, las discusiones que nutren los pasajes del libro han sido entretejidas desde cuatro ejes: Enseñanza de la filosofía, Aprender filosofía, Educación filosófica y Didåctica de la filosofía. Categorías de anålisis que, en la arquitectura del libro. Ejercicios que han nutrido tanto a la filosofía como a la misma enseñanza. Tres maneras de problematizar, tres maneras de conversar, tres maneras de preguntar
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