7,774 research outputs found

    On the Analysis of the Contact Conditions in Temporomandibular Joint Prostheses

    Get PDF
    Temporomandibular joint replacement (TMJR) is a complex surgical procedure in which the artificial joints available must assure the anatomical reconstruction and guarantee a good range of the natural temporomandibular joint (TMJ) movements. With this aim, different types of TMJ prostheses, including the stock prosthetic system and custom-made prostheses, are being currently implanted. Although temporomandibular joint replacements (TMJRs) are expected to accomplish their function during a number of years, they might actually fail and need to be replaced. This paper analyzes different design factors affecting the contact stress distributions within the TMJ prosthesis interface, which are consequently involved in their deterioration and final failure of the prosthetic device. With this purpose, a numerical model based on finite elements has been carried out in order to evaluate the stress states attained in different prosthesis configurations corresponding to general types of TMJ prostheses. On the other hand, the actual degradation of resected implants has been evaluated via optical microscopy. The linkage between the numerical simulations performed and experimental evidence allowed the authors to establish the different wear and damage mechanisms involved in the failure of stock TMJ prostheses. Indeed, the results obtained show that the contact stresses at the interface between the mandible and the glenoid fossa components play a key role in the failure process of the TMJR devices

    Vegetable protein isolates

    Get PDF
    This chapter discusses the importance of vegetable proteins as functional ingredients in food formulations. It provides an overview of the main chemical components, world production, history and food applications of the main vegetable protein sources (legumes, cereals, oilseeds, roots and green leaves), with special emphasis on soybean, pea, and wheat. The chapter includes a description of the composition and structure of the main protein fractions, and a general approach to protein extraction, purification and processing technology to prepare protein meals, concentrates and isolates. In addition, the technologically important functional properties of vegetable protein preparations are described. Finally, nutritional and health effects, as well as the regulatory status of vegetable protein products are examined.Spanish Ministry of Science and Innovation.Peer reviewe

    Recent Approaches for the Manufacturing of Polymeric Cranial Prostheses by Incremental Sheet Forming

    Get PDF
    This paper presents recent research experiences developed with the aim of manufacturing cranial prostheses in polymeric sheet using Incremental Sheet Forming (ISF) technologies. With this purpose, different approaches have been carried out in Single-Point Incremental Forming (SPIF) and Two-Point Incremental Forming (TPIF) in order to produce customized cranial implants using different polymeric materials. In this context, this research work provides a methodology to design and manufacture polymer customized cranial prostheses using the ISF technologies starting from a patient’s computerized tomography (CT). The results demonstrate the potential of manufacturing polymeric cranial prostheses by ISF in terms of the high formability achievable and show the appropriate geometrical accuracy at affordable manufacturing costs provided by these processes.Ministerio de Economía y Competitividad DPI2015-64047-

    The Ca II infrared triplet's performance as an activity indicator compared to Ca II H and K

    Full text link
    Aims. A large number of Calcium Infrared Triplet (IRT) spectra are expected from the GAIA- and CARMENES missions. Conversion of these spectra into known activity indicators will allow analysis of their temporal evolution to a better degree. We set out to find such a conversion formula and to determine its robustness. Methods. We have compared 2274 Ca II IRT spectra of active main-sequence F to K stars taken by the TIGRE telescope with those of inactive stars of the same spectral type. After normalizing and applying rotational broadening, we subtracted the comparison spectra to find the chromospheric excess flux caused by activity. We obtained the total excess flux, and compared it to established activity indices derived from the Ca II H & K lines, the spectra of which were obtained simultaneously to the infrared spectra. Results. The excess flux in the Ca II IRT is found to correlate well with RHKR_\mathrm{HK}' and RHK+R_\mathrm{HK}^{+}, as well as SMWOS_\mathrm{MWO}, if the BVB-V-dependency is taken into account. We find an empirical conversion formula to calculate the corresponding value of one activity indicator from the measurement of another, by comparing groups of datapoints of stars with similar B-V.Comment: 16 pages, 15 figures. Accepted for publication in Astronomy & Astrophysic

    Vector magnetic hysteresis of hard superconductors

    Full text link
    Critical state problems which incorporate more than one component for the magnetization vector of hard superconductors are investigated. The theory is based on the minimization of a cost functional C[H(x)]{\cal C}[\vec{H}(\vec{x})] which weighs the changes of the magnetic field vector within the sample. We show that Bean's simplest prescription of choosing the correct sign for the critical current density JcJ_c in one dimensional problems is just a particular case of finding the components of the vector Jc\vec{J}_c. Jc\vec{J}_c is determined by minimizing C{\cal C} under the constraint JΔ(H,x)\vec{J}\in\Delta (\vec{H},\vec{x}), with Δ\Delta a bounded set. Upon the selection of different sets Δ\Delta we discuss existing crossed field measurements and predict new observable features. It is shown that a complex behavior in the magnetization curves may be controlled by a single external parameter, i.e.: the maximum value of the applied magnetic field HmH_m.Comment: 10 pages, 9 figures, accepted in Phys. Rev.

    Análisis del comportamiento de los consumidores ante el Factor Precio en el mercado de calzado para corredores

    Get PDF
    In Spain 2,274,074 million pairs of shoes were sold to runners (about 175 million of euros). The economic sector of sports equipment for runners may be living its best moment except for as outrageous war of brands and prices that some authors describe. This study examines perceptions of consumers regarding the footwear market for runners. It was designed and validated a questionnaire to 274 runners (10 km, half marathon or marathon). The technical variables such as comfort, lightness, cushioning and durability are more appreciated than price. Only the aesthetic has a lower score. The price is not the most important factor in the purchase decision. Men prefer a better price than technical and aesthetic features as well as the most experienced and long distance runners.En 2013 se vendieron en España 2.274.074 millones de pares de zapatillas para corredores (cerca de 175 millones de euros). El sector económico del material deportivo para corredores podría estar viviendo su mejor momento, si no fuera por lo que algunos califican como desaforada guerra de precios y marcas. Este estudio analiza las percepciones de los consumidores respecto del mercado del calzado para corredores. Se diseñó y validó un cuestionario dirigido a 274 corredores populares (de 10 km, media maratón o maratón). Las variables técnicas como comodidad, ligereza, amortiguación y durabilidad son más apreciadas que el precio. Sólo la estética tiene una puntuación menor. El precio no es el factor más importante para la decisión de compra en ninguno de los grupos de encuestados. Los hombres prefieren un mejor precio que otras características técnicas y estéticas que las mujeres, así como los corredores más experimentados y de larga distancia

    Study of paediatric patients with the clinical and biochemical phenotype of glucose transporter type 1 deficiency syndrome.

    Get PDF
    [ES] Introducción El síndrome de déficit del transportador de glucosa cerebral (GLUT1DS) puede presentar fenotipos variados, incluyendo epilepsia, déficit intelectual y trastorno del movimiento. La mayoría presenta hipoglucorraquia y/o defectos en el gen SLC2A1, aunque existen pacientes sin hipoglucorraquia y otros con genética de SLC2A1-negativa, o con defectos en otros genes y fenotipo compatible. Objetivos Describir las características clínicas, bioquímicas y genéticas y realizar un análisis univariante de un grupo de pacientes con fenotipo clínico y bioquímico de GLUT1DS, con o sin genética SLC2A1-positiva. Material y métodos Se incluyeron 13 pacientes con criterios clínico-bioquímicos de GLUT1DS. Se realizó secuenciación de SLC2A1 y MLPA. En los casos negativos se realizó exoma clínico. Resultados Seis presentaron fenotipo clásico, 2 discinesia paroxística, 2 trastornos del movimiento complejo, 2 ausencias precoces y otro presentó epilepsia con ausencias infantiles refractaria a farmacoterapia. Seis fueron SLC2A1-positivos. Y en 5 de los SLC2A1-negativos se identificó otro defecto genético. No hubo diferencias significativas entre los dos grupos en edad de inicio, presentación clínica, microcefalia, discapacidad intelectual ni respuesta a dieta cetogénica. De forma no significativa, los pacientes SCL2A1-positivos presentaron más cambios clínicos en relación con la ingesta (66,7% vs. 28,6%) y mayor persistencia de síntomas motores (66% vs. 28,6%). De forma significativa, presentaron menor glucorraquia (34,5 mg/dl vs. 46 mg/dl, p = 0,04) e índice glucorraquia/glucemia más bajo (0,4 vs. 0,48, p = 0,05) que los SLC2A1-negativos. Conclusiones GLUT1DS puede ser causado por defectos genéticos en otros genes diferentes de SLC2A1 en pacientes con fenotipo compatible, hipoglucorraquia y buena respuesta a dieta cetogénica. [EN] Introduction Glucose transporter type 1 (GLUT1) deficiency syndrome may present a range of phenotypes, including epilepsy, intellectual disability, and movement disorders. The majority of patients present low CSF glucose levels and/or defects in the SLC2A1 gene; however, some patients do not present low CSF glucose or SLC2A1 mutations, and may have other mutations in other genes with compatible phenotypes. Aims We describe the clinical, biochemical, and genetic characteristics of the disease and perform a univariate analysis of a group of patients with clinical and biochemical phenotype of GLUT1 deficiency syndrome, with or without SLC2A1 mutations. Material and methods The study included 13 patients meeting clinical and biochemical criteria for GLUT1 deficiency syndrome. SLC2A1 sequencing and multiplex ligation-dependent probe amplification were performed; exome sequencing was performed for patients with negative results. Results Six patients presented the classic phenotype; 2 paroxysmal dyskinesia, 2 complex movement disorders, 2 early-onset absence seizures, and one presented drug-resistant childhood absence epilepsy. Six patients were positive for SLC2A1 mutations; in the other 5, another genetic defect was identified. No significant differences were observed between the 2 groups for age of onset, clinical presentation, microcephaly, intellectual disability, or response to ketogenic diet. Patients with SLC2A1 mutations presented more clinical changes in relation to diet (66.7% vs. 28.6% in the SLC2A1-negative group) and greater persistence of motor symptoms (66% vs. 28.6%); these differences were not statistically significant. Significant differences were observed for CSF glucose level (34.5 vs. 46 mg/dL, P = .04) and CSF/serum glucose ratio (0.4 vs. 0.48, P < .05).S

    Estudio de pacientes pediátricos con fenotipo clínico y bioquímico de síndrome de déficit de transportador de glucosa cerebral (GLUT-1)

    Get PDF
    [EN] Introduction: Glucose transporter type 1 (GLUT1) deficiency syndrome may present a range of phenotypes, including epilepsy, intellectual disability, and movement disorders. The majority of patients present low CSF glucose levels and/or defects in the SLC2A1 gene; however, some patients do not present low CSF glucose or SLC2A1 mutations, and may have other mutations in other genes with compatible phenotypes. Aims: We describe the clinical, biochemical, and genetic characteristics of the disease and perform a univariate analysis of a group of patients with clinical and biochemical phenotype of GLUT1 deficiency syndrome, with or without SLC2A1 mutations. Material and methods: The study included 13 patients meeting clinical and biochemical criteria for GLUT1 deficiency syndrome. SLC2A1 sequencing and multiplex ligation-dependent probe amplification were performed; exome sequencing was performed for patients with negative results. Results: Six patients presented the classic phenotype; 2 paroxysmal dyskinesia, 2 complex movement disorders, 2 early-onset absence seizures, and one presented drug-resistant childhood absence epilepsy. Six patients were positive for SLC2A1 mutations; in the other 5, another genetic defect was identified. No significant differences were observed between the 2 groups for age of onset, clinical presentation, microcephaly, intellectual disability, or response to ketogenic diet. Patients with SLC2A1 mutations presented more clinical changes in relation to diet (66.7%, vs 28.6% in the SLC2A1-negative group) and greater persistence of motor symptoms (66% vs 28.6%); these differences were not statistically significant. Significant differences were observed for CSF glucose level (34.5 vs 46mg/dL, P=.04) and CSF/serum glucose ratio (0.4 vs 0.48, P<.05). Conclusions: GLUT1 deficiency syndrome may be caused by mutations to genes other than SLC2A1 in patients with compatible phenotype, low CSF glucose level, and good response to the ketogenic diet. [ES] Introducción: El síndrome de déficit del transportador de glucosa cerebral (GLUT1DS) puede presentar fenotipos variados, incluyendo epilepsia, déficit intelectual y trastorno del movimiento. La mayoría presentan hipoglucorraquia y/o defectos en el gen SLC2A1, aunque existen pacientes sin hipoglucorraquia y otros con genética de SLC2A1-negativa, o con defectos en otros genes y fenotipo compatible. Objetivos: Describir las características clínicas, bioquímicas y genéticas y realizar un análisis univariante de un grupo de pacientes con fenotipo clínico y bioquímico de GLUT1DS, con o sin genética SLC2A1-positiva. Material y métodos: Se incluyeron 13 pacientes con criterios clínico-bioquímicos de GLUT1DS. Se realizó secuenciación de SLC2A1 y MLPA. En los casos negativos se realizó exoma clínico. Resultados: Seis presentaron fenotipo clásico, 2 discinesia paroxística, 2 trastornos del movimiento complejo, 2 ausencias precoces y otro presentó epilepsia con ausencias infantiles refractaria a farmacoterapia. Seis fueron SLC2A1-positivos. Y en 5 de los SLC2A1-negativos se identificó otro defecto genético. No hubo diferencias significativas entre los dos grupos en edad de inicio, presentación clínica, microcefalia, discapacidad intelectual ni respuesta a dieta cetogénica. De forma no significativa, los pacientes SCL2A1-positivos presentaron más cambios clínicos en relación con la ingesta (66,7% vs. 28,6%) y mayor persistencia de síntomas motores (66% vs. 28,6%). De forma significativa, presentaron menor glucorraquia (34,5 mg/dl vs. 46 mg/dl, p = 0.04) e índice glucorraquia/glucemia más bajo (0,4 vs. 0,48, p = 0,05) que los SLC2A1-negativos. Conclusiones: GLUT1DS puede ser causado por defectos genéticos en otros genes diferentes de SLC2A1 en pacientes con fenotipo compatible, hipoglucorraquia y buena repuesta a dieta cetogénica.‘‘Identification and clinical and biochemical characterisation of patients with GLUT1DS: treatment monitoring.’’ Translational research project 2017, CIBERER. Coordinator: Dr Luis González Gutiérrez-Solana (GCV6). Participating units: U703 (Artuch); U746 (Pérez); GCV5 (Couce); GCV6 (Gutiérrez-Solana); GCV7 (López Laso); GCV8 (del Toro). Research project: hereditary metabolic disorders.S

    Magnetized strangelets at finite temperature

    Get PDF
    The main properties of magnetized strangelets, namely, their energy per baryon, radius and electric charge, are studied. Temperature effects are also taken into account in order to study their stability compared to the 56Fe isotope and non-magnetized strangelets using the liquid drop model. Massive quarks are considered with the aim to have a more realistic description for strangelets in the astrophysical context and the environment of heavy ion colliders, playing also an important role in the thermodynamical quantities of the quark gas. It is concluded that the presence of a magnetic field tends to stabilize more the strangelets, even when temperature effects are taken into account. Magnetized strangelets in a paired superconductor phase (magnetized color flavor locked phase) are also discussed. It is shown that they are more stable than ordinary magnetized strangelets for typical gap values of the order of O(100) MeV.Comment: 10 pages, 10 figures, discussion extended, new references adde
    corecore