Megalitismo y rituales funerarios

Sin resume

Aprender a enseñar geometría en primaria. Una experiencia en formación inicial de maestros

Es nuestra intención, con la publicación que tienes entre tus manos, presentar una pro- puesta metodológica basada en una experiencia desarrollada durante algunos años en un aula de formación inicial de maestros. Por ello, la estructura de la primera parte sigue el desarrollo de las actividades del aula, con observaciones sobre el proceso de interacción profesor-estu- diantes para Maestros (EM) y entre los estudiantes, así como reflexiones que surgen en el aula, que tienen su fundamento en experiencias anteriores o en aportaciones de diferentes autores. Además, el lenguaje utilizado es coloquial y reflejo del trabajo desarrollado en el aula

VISIR-VLT high resolution study of the extended emission of four obscured post-AGB candidates

The onset of the asymmetry of planetary nebulae (PNe) is expected to occur during the late Asymptotic Giant Branch (AGB) and early post-AGB phases of low- and intermediate-mass stars. Among all post-AGB objects, the most heavily obscured ones might have escaped the selection criteria of previous studies detecting extreme axysimmetric structures in young PNe. Since the most heavily obscured post-AGB sources can be expected to descend from the most massive PN progenitors, these should exhibit clear asymmetric morphologies. We have obtained VISIR-VLT mid-IR images of four heavily obscured post-AGB objects barely resolved in previous Spitzer IRAC observations to analyze their morphology and physical conditions across the mid-IR. The VISIR-VLT images have been deconvolved, flux calibrated, and used to construct RGB composite pictures as well as color and optical depth maps that allow us to study the morphology and physical properties of the extended emission of these sources. We have detected extended emission from the four objects in our sample and resolved it into several structural components that are greatly enhanced in the temperature and optical depth maps. They reveal the presence of asymmetry in three young PNe (IRAS 15534-5422, IRAS 17009-4154, and IRAS 18454+0001), where the asymmetries can be associated with dusty torii and slightly bipolar outflows. The fourth source (IRAS 18229-1127), a possible post-AGB star, is better described as a rhomboidal detached shell. The heavily obscured sources in our sample do not show extreme axisymmetric morphologies. This is at odds with the expectation of highly asymmetrical morphologies in post-AGB sources descending from massive PN progenitors. The sources presented in this paper may be sampling critical early phases in the evolution of massive PN progenitors, before extreme asymmetries develop.Comment: 9 pages, 4 figure

Fijación híbrida de componentes en la artroplastia de revisión de rodilla. Resultados clínicos, radiológicos y gammagráficos a medio plazo.

Introducción: La fijación híbrida en la artroplastia de revisión de rodilla es uno de los tratamientos más comunes en los aflojamientos protésicos. Material y métodos: Estudiamos una serie de 19 pacientes intervenidos mediante el sistema de revisión P.F.C. TC-3 Sigma (De Puy) desde Enero 2001 a Diciembre de 2004. La edad media fue de 73.4 años. Los pacientes fueron estudiados clínica, radiológica y gammagráficamente mediante la escala de la Sociedad Americana de la Rodilla (KSS), la escala radiológica de la Sociedad Americana de la Rodilla modificada por Fehring y el índice de salud SF-36. El tiempo de seguimiento medio fue de dos años. Resultados: La escala clínica de la rodilla aumentó de 27,8 puntos a 58,4 (11-95) y la funcional de 37,4 a 59,8 (25-100). Según el estudio radiográfico 17 de los 19 implantes femorales no cementados fueron definidos estables, dos se catalogaron de posible aflojamiento que requerían seguimiento estrecho, ningún caso se definió como movilizado. En el implante tibial sólo un caso se consideró posiblemente aflojado, el resto eran estables. Respecto al estudio gammagráfico la prueba resultó positiva en 12 tibias y 8 fémures. Se obtuvo inferencia significativa entre el índice SF-36 y la escala de la KSS. Conclusiones: El sistema PFC TC 3 Sigma ha demostrado unos buenos resultados a medio plazo. Mediante la exploración y el sistema de escalas KSS hemos podido obtener conclusiones reales sobre la estabilidad radiológica y los resultados a largo plazo de los estudios de imagen y su posible relación en el aflojamiento aséptico.Background: The revision total knee arthroplasty using hybrid stem fixation is one of the most common methods in the prosthesis loosening treatment. Methods: We retrospectively reviewed 19 patients who under- went revision total knee PFC TC-3 Sigma performed between January 2001 to December 2004. The averaged age was 73.4 years at the time of operation. Patients were evaluated clini- cally, radiographic and scintygraphic using the American Knee society score, the Knee Society total knee arthroplasty roent- genographic evaluation modified by Fehring and the SF-36. The average follow-up was two years. Results: The average knee score improved from 27,8 points to 58,4 (11-95). The average functional score improved from 37,4 points to 59,8 (25-100). According to the radiographic study 17 of the 19 femoral implants with cementless stems were considered stable, 2 were categorized as possibly loose requiring close follow up, and none were loose. In the tibial implants only one case were considered possibly loose, the rest was stable. With respect to scintygraphic evaluation the bone scan was posi- tive in 12 cases in tibia and 8 in femur. A estatistical signifi- cance was found between the SF-36 and the KSS score. Conclusion: The PFC TC-3 Sigma system has demonstrated a good midterm results. By means the exploration and the KSS score we have obtained real conclusions on radiographic sta- bility and scintigraphic scan. It will be necessary to consider the long term results of the images studies and the possible relation with the aseptic loosening

Desalineación rotacional del implante tibial en artroplastia total de rodilla: estudio con navegación

Objetivo: Estudiar la rotación del implante tibial y el desajuste rotacional de los implantes femoral y tibial en los 19 casos intervenidos de artroplastia total de rodilla modelo Natural II, con sistema de navegación Navitrack® (Zimmer®). Material y Métodos: Estudio prospectivo en una serie consecutiva de 19 casos de artrosis de rodilla. Se analizaron las medidas realizadas con un sistema de navegación: 1- el ángulo entre la línea que va desde la inserción del Ligamento Cruzado Posterior al tercio medio de la tuberosidad tibial anterior y la línea anteroposterior del implante tibial para determinar la rotación del mismo; 2- el ángulo de la línea femoral epicondílea con el bloque de corte que nos dará la rotación del implante femoral. Resultados: La rotación media del implante tibial ha sido - 0,011º ± 0,533 (r: -0,800 / 1,000). La rotación del implante femoral con relación a la línea epicondílea ha sido -3,174º ± 4,733 (r: -12,300 / 7,700). El ajuste rotacional femorotibial ha sido -2,963º ± 4,649 (r: -11,500/ 6,700). Encontramos una alineación rotacional femorotibial en el 63% de los casos. Conclusiones: El sistema de navegación utilizado permite colocar el implante tibial con una rotación adecuada así como evitar un desajuste rotacional entre los implantes femoral y tibial. Actualmente se consideran de forma combinada las rotaciones de los implantes, lo que tiene gran importancia para evitar los problemas rotulianos así como el desgaste del polietileno.To study the rotational alignment of the tibial implant in 19 patients who underwent total knee arthroplasty by surgical navigation system. Material and Methods: Prospective analysis of 19 consecutive patients with knee osteoarthritis. References obtained by the computerized navigation were: 1- the angle between the line from the insertion of the posterior cruciate ligament to the medial tibial tuberosity and the anteroposterior tibial implant line to study the tibial rotation; 2- the angle between the epicondyle line and the cut piece to study the femoral rotation. Results: The media tibial implant rotation was - 0,011º ± 0,533 (r: -0,800/ 1,000). The femoral implant rotation was -3,174º ± 4,733 (r: -12,300 / 7,700). The mean angle of the rotational mismatch of the components was -2,963º ± 4,649 (r: -11,500/ 6,700). There was a good femorotibial mismatch in 63%. Conclusions: The navigation system helps us to put the tibial implant in a good rotation and so a good femorotibial mismatch. Actually we study the combined rotation of the implants to decrease the patelofemoral problems and the polyethylene damage

"La efigie cabal del recuerdo". El arquitecto ante al hecho fotográfico

[ES] Sin resumenGómez-Blanco Pontes, AJ. (2003). "La efigie cabal del recuerdo". El arquitecto ante al hecho fotográfico. EGA. Revista de Expresión Gráfica Arquitectónica. (8):70-75. https://doi.org/10.4995/ega.2003.10352SWORD7075

Tunneling mechanism of light transmission through metallic films

A mechanism of light transmission through metallic films is proposed, assisted by tunnelling between resonating buried dielectric inclusions. This is illustrated by arrays of Si spheres embedded in Ag. Strong transmission peaks are observed near the Mie resonances of the spheres. The interaction among various planes of spheres and interference effects between these resonances and the surface plasmons of Ag lead to mixing and splitting of the resonances. Transmission is proved to be limited only by absorption. For small spheres, the effective dielectric constant can be tuned to values close to unity and a method is proposed to turn the resulting materials invisible.Comment: 4 papges, 5 figure

Histone Extraction From Human Articular Cartilage for the Study of Epigenetic Regulation in Osteoarthritis

[Abstract] Osteoarthritis (OA) is a chronic disease that affects articular cartilage, causing its degeneration. Although OA is one of the most prevalent pathologies globally, there are no definitive treatments available. Recently, research has focused on elucidating the complex interplay that takes place between inflammatory processes and epigenetic regulation, showing that histone post-translational modifications (PTMs) can exert a pronounced effect on the expression of OA-related genes. OA chondrocytes enhance the production of interleukin 1β (IL-1β) and interleukin 8 (IL-8), which are epigenetically regulated. These cytokines upregulate the synthesis of matrix metalloproteinases (MMPs) and aggrecanases, which promote the extracellular matrix (ECM) destruction. This motivates the study of histone PTMs to investigate the epigenetic regulation of proinflammatory molecules, but the absence of specific protocols to extract histones from human articular cartilage has complicated this task. The lack of effective methods can be explained by the structural complexity and low cellularity of this tissue, which are responsible for the biomechanical properties that allow the movement of the joint but also complicate histone isolation. Here, we provide a histone extraction procedure specifically adapted for cryopreserved human articular cartilage that can be useful to understand epigenetic regulation in OA and accelerate the search for novel strategies.This research was funded by Instituto de Salud Carlos III (grant No. PI19/01213 and grant No. RD21/0002/0009), integrated in the National Plan for Scientific Research, Development and Technological Innovation 2017–2020 and funded by the ISCIII —General Subdirection of Assessment and Promotion of the Research—European Regional Development Fund (FEDER) “A way of making Europe”. M.C.D.A is supported by the Miguel Servet program from Fondo Investigación Sanitaria-Spain (CP18/00084). Also, by Xunta de Galicia (grant No. IN607A 2021/7). The Biomedical Research Networking Center (CIBER) is an initiative from Instituto de Salud Carlos III (ISCIII)Xunta de Galicia; IN607A 2021/

Growth, water relations and ion accumulation in Phlomis purpurea plants under water deficit and salinity

The effect of different levels of water deficit and salinity on physiological and morphological alterations in Phlomis purpurea plants was studied to evaluate their adaptability to such conditions. P. purpurea plants growing under greenhouse conditions were subjected to four irrigation treatments between November and May 2008: control (C, 1 dS m-1), moderate water deficit (MWD, 1dS m-1, 60% of the control), severe water deficit (SWD, 1 dS m-1, 40% of the control) and saline (S, 4 dS m-1). Aerial dry weight decreased with salinity, response that was more marked in the water deficit treatments, especially SWD. Stem diameter and leaf number were similarly reduced in both water deficit treatments, while leaf area also decreased in saline treated plants. Throughout the experiment, plant height was similar in both control and saline treated plants and was inhibited 10 weeks after application of the deficit irrigation onwards. Only at the end of the experiment were there significant differences in plant height between all treatments. Plants irrigated with saline water had higher Na+ concentrations in their leaves than in their roots and shoots, while Cl- concentrations were similar in leaves and roots, suggesting some resistance to the movement of the latter ions from root to shoots. The accumulation of salt in the leaves was associated with osmotic adjustment, which maintained midday leaf turgor in saline treated plants. However, no osmotic adjustment was observed in plants submitted to water stress. The results indicate that the effect of osmotic stress due to water deficit was more severe than the toxic effect of salt.This work was supported by the projects: CICYT (AGL 2008-05258-C02-1-2), CDTI (IDI-20070868) and Convenio de la Consejería de Agricultura y Agua de la Región de Murcia-UPCT-CEBAS, 2008.Peer Reviewe