533 research outputs found

    Heritage Stone 5. Silicified Granites (Bleeding Stone and Ochre Granite) as Global Heritage Stone Resources from Ávila, Central Spain

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    Silicified granites were used to build the Romanesque monuments in the city of Ávila, Spain. The building stones comprise two types of granite based on their technical properties and colour: Bleeding Stone (Piedra Sangrante) and Ochre Granite (Caleño). They were used as a facing stone in the city´s Romanesque monuments of the 12th century (e.g. the cathedral and church of San Pedro), and the famous city walls that constitute the best example of military Romanesque Spanish architecture. During the Gothic and Renaissance periods of the 13th and 15th centuries, silicified granites were used mainly to build ribbed vaults, the voissoirs of the arches, and elements of the windows in the monuments of Ávila.    Silicified granites are found in the intermediate and upper part of a complex palaeoweathering zone or mantle developed on the Iberian Hercynian Basement which underlies much of the western Iberian Peninsula. The silicification occurred during tropical conditions in the Mesozoic. The weathered mantle was truncated by Alpine tectonic movements during the Tertiary, and its remnants were unconformably overlain by more recent sediments in the western and southern part of the Duero Basin and along the northern edge of the Amblés Valley graben. The historical, and now protected, quarry is located in a village called La Colilla, about 5 km from the city of Ávila. Currently, this stone is exploited only for restoration work performed in the city, for example the Walls of Ávila, and the church of San Pedro. The resource is limited and being depleted, so the stone will be scarce in the near future. Consequently, these silicified granites should be recognized as a Global Heritage Stone Resource.   The specific technical properties of these stones and their historic use, decay patterns, durability, and suitability for conservation treatments combine to support its designation as a Global Heritage Stone Resource.RÉSUMÉDes granites silicifiés ont été utilisés pour construire les monuments romans dans la ville d’Ávila, en Espagne.  Les pierres de construction comprennent deux types de granite selon leurs propriétés techniques et leur couleur : Bleeding Stone (Piedra sangrante) et Ochre Granite (Caleño).  Ils ont été utilisés comme pierre de revêtement de monuments romans du 12ème siècle de la ville (par exemple la cathédrale et de l'église de San Pedro), et pour les célèbres remparts de la ville qui constituent le meilleur exemple de l'architecture espagnole romane militaire.  Durant les périodes gothique et Renaissance des 13e et 15e siècles, les granites silicifiés ont été utilisés principalement pour construire des croisés d'ogives, des voussoirs d’arcs et des éléments de fenêtres des monuments d’Ávila.     Les granites silicifiés se trouvent dans la partie intermédiaire et supérieure d'une zone complexe de paléo-altération ou de manteau développée sur le socle ibérique hercynien qui supporte une grande partie de la péninsule ibérique occidentale.  La silicification s’est produite dans des conditions tropicales au Mésozoïque.  Le matériau mantélique altéré a été tronqué par des mouvements tectoniques alpins au cours du Tertiaire, et ses restes ont été recouverts en discordance par des sédiments plus récents dans la partie ouest et sud du bassin de Duero, et le long de la bordure nord de la vallée en graben d’Amblés.  L’ancienne carrière, maintenant protégée, est située dans un village appelé La Colilla, à environ 5 km de la ville d’Ávila.  Actuellement, cette pierre est exploitée uniquement pour les travaux de restauration effectués dans la ville, par exemple les murs d’Ávila, et l'église de San Pedro.  La ressource est limitée et en voie d'épuisement, de sorte que la pierre sera rare dans un proche avenir.  Par conséquent, ces granites silicifiés devraient être reconnus en tant que pierre du Patrimoine mondial des ressources en pierre.   Les propriétés techniques spécifiques de ces pierres et leur valeur historique, leurs modes de désintégration, leur durabilité et leur pertinence pour la conservation patrimoniale justifient leur désignation en tant que roche du Patrimoine mondial des ressources en pierre.                                                             Traduit par le Traducteu

    Effect of plant density on yield components of common bean grown under inter-Andean Mountain conditions of Ecuador

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    El fréjol es un cultivo importante debido a su alto valor nutritivo. En los últimos años la producción en Ecuador de este cultivo ha disminuido drásticamente debido entre otros factores a ineficientes procesos y falta de tecnificación en la producción. Entender cómo se generan y determinan los componentes del rendimiento del grano es primordial para diseñar estrategias que permitan aumentar el rendimiento del cultivo. En este estudio, se modificó la densidad de plantas con el objetivo de evaluar su impacto sobre el número de granos, peso de granos y rendimiento, bajo condiciones de campo en una región andina de Ecuador. Se realizaron dos experimentos sembrados en fechas distintas, donde se evaluaron densidades de plantas contrastantes 4 y 11 plantas m-2. El efecto de los tratamientos se estudió sobre la duración del periodo emergencia - antesis, el número de vainas llenas y vanas, el número de granos, el peso seco de 100 granos y el rendimiento de grano. Los resultados indican que la densidad de plantas tiene un efecto significativo (p<0,05) sobre el rendimiento, alcanzando un promedio de 257,15 g m-2 en alta densidad y 151,45 g m-2 en baja densidad. Los componentes principales del rendimiento mostraron una respuesta distinta a la modificación de la densidad de plantas; el número de granos presentó una fuerte variabilidad y fue positivamente asociado con el rendimiento final del grano (p<0,05), mientras que el peso del grano no fue afectado.Common bean is an important crop due to its high nutritional value. However, its production in Ecuador has decreased due to biotic and abiotic factors. Understanding the mechanisms that determine the yield components of this crop is essential to establish strategies that allow increasing the yield. In this study, the plant density was modified to evaluate its impact on yield and its two main components, the grain number and grain weight under field conditions in an Andean region of Ecuador. Two experiments planted on different dates were performed, where two planting densities 4 and 11 plants m-2 were evaluated. The effect of the treatments was studied on the length of the period, from emergence to anthesis, the number of full and empty pods, grain number, 100 grain weight and grain yield. The results indicate that the plant density has a significant effect (p<0.05) on the yield, reaching an average of 257.15 g m-2 in high density, and 151.45 g m-2 in low density. The yield main components showed a different response to plant density modification; the grain number exhibited a strong variability and was positively associated with final grain yield (p<0.05) while the grain weight was not affected.

    Pyroglutamic acidosis by glutathione regeneration blockage in critical patients with septic shock

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    Aim: The aim of this study was to evaluate oxidative stress from glutathione depletion in critically ill patients with a septic shock through the abnormal presence of pyroglutamic acid (PyroGlu) in the urine (indirectly) and through its serum level (directly). Methods: This was a prospective analytical study of 28 critically ill patients with a septic shock who were monitored from admission (initial) to 3 days of stay (final) in the intensive care unit (ICU). Data collected included PyroGlu and glutamic acid (Glu) using liquid chromatography/mass spectrometry, and glutathione peroxidase (GPX) activity with a colorimetric assay. The differences in Glu, PyroGlu, and GPX activity between the septic shock group and healthy control group serving as reference values were evaluated using the Mann–Whitney test. The correlations between Glu, PyroGlu, and GPX activity and clinical outcomes were determined using Spearman’s correlation coefficient. Results: In patients with septic shock, serum and urine PyroGlu levels were higher, erythrocyte GPX activity/gr Hb was lower, and urine Glu levels were lower compared to healthy control reference values, for both initial and final values. Initial serum Glu levels were also lower. Serum PyroGlu levels had a correlation with both initial and final serum Glu levels; levels also correlated in the urine. Initial serum Glu correlated with the days of mechanical ventilation (P = 0.016) and the days of ICU stay (P = 0.05). Urine Glu/mg creatinine correlated with APACHE II (P = 0. 030). This positive correlation observed for serum Glu was not observed for PyroGlu. Conclusions: The current study found that septic patients have higher levels of PyroGlu, lower levels of Glu, and lower erythrocyte GPX activity, suggesting that these biomarkers could be used as an indicator of glutathione depletion. In addition, Glu is related to severity parameters. This study can guide future studies on the importance of monitoring the levels of pyroglutamic acidosis in critical patients with septic shock in order to preserve the oxidative status and its evolution during the stay in the ICU.Financial support for the study was provided by Project FIS PI10/1993 from the Spanish Carlos III Health Institute and FEDER European Funds

    Preventing incisional ventral hernias: important for patients but ignored by surgical specialities? A critical review.

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    Purpose Incisional ventral hernias (IHs) are a common complication across all surgical specialities requiring access to the abdomen, pelvis, and retroperitoneum. This public health issue continues to be widely ignored, resulting in appreciable morbidity and expenses. In this critical review, the issue is explored by an interdisciplinary group. Methods A group of European surgeons encompassing representatives from abdominal wall, vascular, urological, gynecological, colorectal and hepato-pancreatico-biliary surgery have reviewed the occurrence of His in these disciplines. Results Incisional hernias are a major public health issue with appreciable morbidity and cost implications. General surgeons are commonly called upon to repair IHs following an initial operation by others. Measures that may collectively reduce the frequency of IH across specialities include better planning and preparation (e.g. a fit patient, no time pressure, an experienced operator). A minimally invasive technique should be employed where appropriate. Our main recommendations in midline incisions include using the ‘small bites’ suture technique with a ≥ 4:1 suture-to-wound length, and adding prophylactic mesh augmentation in patients more likely to suffer herniation. For off-midline incisions, more research of this problem is essential. Conclusion Meticulous closure of the incision is significant for every patient. Raising awareness of the His is necessary in all surgical disciplines that work withing the abdomen or retroperitoneum. Across all specialties, surgeons should aim for a < 10% IH rate.pre-print146 K

    Characterization of new materials for fiberoptic dosimetry

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    In this work we have investigated the radioluminescence (RL) characteristics of three materials (Mg2SiO4:Tb, CsY2F7:Tb and KMgF3:Sm) in order to determine whether they can be used as real time dosimeters in the the framework the fiberoptic dosimetry (FOD) technique. This technique is based on the use of scintillating materials coupled to the end of an optical fiber, which collects the light emitted by the scintillator during irradiation. Since usually the intensity of the emitted light is proportional to the dose-rate, the technique provides a reliable measuring method, which can be employed in radiotherapy treatments.17th Biennial Congress of the Argentinean-Bioengineering-Society/6th Clinical Engineering Conference, Oct 14-16, 2009, Rosario, Argentin

    Modelling of corrosion-induced cover cracking in reinforced concrete by an embedded cohesive crack finite element

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    Corrosion of a reinforcement bar leads to expansive pressure on the surrounding concrete that provokes internal cracking and, eventually, spalling and delamination. Here, an embedded cohesive crack 2D finite element is applied for simulating the cracking process. In addition, four simplified analytical models are introduced for comparative purposes. Under some assumptions about rust properties, corrosion rate, and particularly, the accommodation of oxide products within the open cracks generated in the process, the proposed FE model is able to estimate time to surface cracking quite accurately. Moreover, emerging cracking patterns are in reasonably good agreement with expectations. As a practical case, a prototype application of the model to an actual bridge deck is reported

    Efecto de la densidad de plantas sobre los componentes del rendimiento de fréjol cultivado en condiciones de campo en un valle interandino de Ecuador

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    El fréjol es un cultivo importante debido a su alto valor nutritivo. En los últimos años la producción en Ecuador de este cultivo ha disminuido drásticamente debido entre otros factores a ineficientes procesos y falta de tecnificación en la producción. Entender cómo se generan y determinan los componentes del rendimiento del grano es primordial para diseñar estrategias que permitan aumentar el rendimiento del cultivo. En este estudio, se modificó la densidad de plantas con el objetivo de evaluar su impacto sobre el número de granos, peso de granos y rendimiento, bajo condiciones de campo en una región andina de Ecuador. Se realizaron dos experimentos sembrados en fechas distintas, donde se evaluaron densidades de plantas contrastantes 4 y 11 plantas m-2. El efecto de los tratamientos se estudió sobre la duración del periodo emergencia - antesis, el número de vainas llenas y vanas, el número de granos, el peso seco de 100 granos y el rendimiento de grano. Los resultados indican que la densidad de plantas tiene un efecto significativo (p<0,05) sobre el rendimiento, alcanzando un promedio de 257,15 g m-2 en alta densidad y 151,45 g m-2 en baja densidad. Los componentes principales del rendimiento mostraron una respuesta distinta a la modificación de la densidad de plantas; el número de granos presentó una fuerte variabilidad y fue positivamente asociado con el rendimiento final del grano (p<0,05), mientras que el peso del grano no fue afectado

    Fault kinematics in northern Central America and coupling along the subduction interface of the Cocos Plate, from GPS data in Chiapas (Mexico), Guatemala and El Salvador

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    International audienceNew GPS measurements in Chiapas (Mexico), Guatemala and El Salvador are used to constrain the fault kinematics in the North America (NA), Caribbean (CA) and Cocos (CO) plates triple junction area. The regional GPS velocity field is first analysed in terms of strain partitioning across the major volcano-tectonic structures, using elastic half-space modelling, then inverted through a block model. We show the dominant role of the Motagua Fault with respect to the Polochic Fault in the accommodation of the present-day deformation associated with the NA and CA relative motion. The NA/CA motion decreases from 18-22 mm yr−1 in eastern Guatemala to 14-20 mm yr−1 in central Guatemala (assuming a uniform locking depth of 14-28 km), down to a few millimetres per year in western Guatemala. As a consequence, the western tip of the CA Plate deforms internally, with ≃9 mm yr−1 of east-west extension (≃5 mm yr−1 across the Guatemala city graben alone). Up to 15 mm yr−1 of dextral motion can be accommodated across the volcanic arc in El Salvador and southeastern Guatemala. The arc seems to mark the northern boundary of an independent forearc sliver (AR), pinned to the NA plate. The inversion of the velocity field shows that a four-block (NA, CA, CO and AR) model, that combines relative block rotations with elastic deformation at the block boundaries, can account for most of the GPS observations and constrain the overall kinematics of the active structures. This regional modelling also evidences lateral variations of coupling at the CO subduction interface, with a fairly high-coupling (≃0.6) offshore Chiapas and low-coupling (≃0.25) offshore Guatemala and El Salvador

    Targeted glutamate supply boosts insulin concentrations, ovarian activity, and ovulation rate in yearling goats during the anestrous season

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    The neuroendocrine regulation of the seasonal reproductive axis requires the integration of internal and external signals to ensure synchronized physiological and behavioral responses. Seasonal reproductive changes contribute to intermittent production, which poses challenges for optimizing goat product yields. Consequently, a significant objective in seasonal reproduction research is to attain continuous reproduction and enhance profitability in goat farming. Glutamate plays a crucial role as a modulator in several reproductive and metabolic processes. Hence, the aim of this study was to evaluate the potential impact of exogenous glutamate administration on serum insulin concentration and ovarian function during the out-of-season period in yearling goats. During the anestrous season, animals were randomly located in individual pens to form two experimental groups: (1) glutamate (n = 10, live weight (LW) = 29.1 ± 1.02 kg, body condition score (BCS) = 3.4 ± 0.2 units) and (2) control (n = 10; LW = 29.2 ± 1.07 kg, BCS = 3.5 ± 0.2), with no differences (p < 0.05) regarding LW and BCS. Then, goats were estrus-synchronized, and blood sampling was carried out for insulin quantification. Ovaries were ultrasonographically scanned to assess ovulation rate (OR), number of antral follicles (AFs), and total ovarian activity (TOA = OR + AF). The research outcomes support our working hypothesis. Certainly, our study confirms that those yearling goats treated with exogenous glutamate displayed the largest (p < 0.05) insulin concentrations across time as well as an augmented (p < 0.05) out-of-season ovarian activity
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