113 research outputs found

    Seismic Microzonation of the Texcoco Lake Area, Mexico

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    This paper presents some of the most relevant results obtained from field, laboratory and analytical investigations aimed at characterizing the seismic environment prevailing at the Texcoco lake region, in the Valley of Mexico, with the goal of developing a microzonation. In particular, this study focuses on an area of 19.0 by 5.5 km2, which has been instrumented with four seismological stations: TXSO, TXS1, TXS2 and TXCH that have recorded ground motions for at least 15 years. Field investigations were conducted to define the subsoil conditions underneath each station. Dynamic testing in these high plasticity clays was carried out to establish the variation of shear stiffness and damping with strain level. Ground motion definition was achieved through empirically derived response spectra obtained from sets of earthquake ground motions recorded at a nearby station located in soft soil, which were deconvolved to the base rock. An statistical analysis using random shear wave velocity profiles and an stochastic site response analysis was used to developed sets of response spectra to reduce uncertainties associated with soil properties determination and seismic environment characterization. The final proposed response spectra for each studied point were developed from the envelope plus one standard deviation computed at each ground motion station. These spectra show good agreement both in frequency content and spectral ordinates with those obtained directly from measurements taken at these seismological stations. Finally equations to construct the proposed response spectra were proposed

    Numerical Study of the Seismic Response of an Urban Overpass Support System

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    A strategic urban overpass is to be built in the so-called transition and hill zones in Mexico City. The subsoil conditions at these zones typically consist on soft to stiff clay and medium to dense sand deposits, randomly interbedded by loose sand lenses, and underlain by rock formations that may outcrop in some areas. Several critical supports of this overpass are going to be instrumented with accelerometers, inclinometers and extensometers to assess their seismic performance during future earthquakes and to generate a database to calibrate soil-structure-interaction numerical models. This paper presents the seismic performance evaluation of one of these supports. The support foundation is a 3.6 by 4.6 m mat, structurally connected to four cast-in-place 0.80 m diameter piles. A finite elements model of the soil-foundation-structure system was developed. Initially, the model was calibrated analyzing the seismic response that an instrumented bridge support exhibited during the June 15th, 1999 Tehuacan (Mw=7) Earthquake. This bridge is located also within the surroundings of Mexico City, but at the lake zone, where highly compressible clays are found. The computed response was compared with the measured response in the free field, box foundation, and structure. Once the model prediction capabilities were established, the seismic response of the critical support of the urban overpass was evaluated for the design earthquake in terms of transfer functions and displacement time histories

    Non-Centrosymmetric Homochiral Supramolecular Polymers of Tetrahedral Subphthalocyanine Molecules

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    This is the peer reviewed version of the following article: Angewandte Chemie - International Edition 54.8 (2015): 2543-2547, which has been published in final form at http://dx.doi.org/10.1002/anie.201411272. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingA combination of spectroscopy (UV/Vis absorption, emission, and circular dichroism), microscopy (AFM and TEM), and computational studies reveal the formation of non-centrosymmetric homochiral columnar subphthalocyanine assemblies. These assemblies form through a cooperative supramolecular polymerization process driven by hydrogen-bonding between amide groups, ŌÄ-ŌÄ stacking, and dipolar interactions between axial B-F bondsFunding from MINECO (CTQ2011-24187, CTQ2011-23659, CTQ2011-23659 and 02, CTQ2012-31914, and CTQ2012-35513-C02-01), CAM (S2013/MIT-2841 FOTO-CARBON), GVA (PROMETEO/2012/053

    150 a√Īos del descubrimiento del yacimiento c√°mbrico de Murero (Cadenas Ib√©ricas, NE Espa√Īa).

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    The lower-middle Cambrian palaeontological site of Murero (Cadenas Ibéricas, NE Spain) is a classical locality of the Cambrian in Europe. The site was first reported by the French geologist Edouard de Verneuil in 1862, and now it achieves 150 years of geological works contributing to a better knowledge of the Cambrian Period. Murero is an exceptional Lagerstätte because the coexistence of both skeletal and soft-bodied groups along a continuous record of ca. 8 million years, which is subdivided into 14 trilobite zones. Murero was the first palaeontological site in Spain to obtain the highest protection figure (Bien de Interés Cultural, BIC) from the Spanish Administration in 1997. Since then, the educational and social projection of the site is continuously increasing

    Agrárpiaci Jelentések, Baromfi

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    Amerikai Egyes√ľlt √Āllamok agr√°rminiszt√©rium√°nak (USDA) m√°jusban megjelent jelent√©se szerint az USA csirkeh√ļstermel√©se 4,6 milli√≥ tonna k√∂r√ľl alakult 2017 elsŇĎ negyed√©v√©ben, ami 2 sz√°zal√©kkal haladta meg az elŇĎzŇĎ √©v azonos idŇĎszak√°nak kibocs√°t√°s√°t. Az Eur√≥pai Bizotts√°g adatai alapj√°n 2017 elsŇĎ 20 het√©ben 178 eur√≥/100 kilogramm volt az eg√©sz csirke uni√≥s √°tlag√°ra, kism√©rt√©kben cs√∂kkent az elŇĎzŇĎ √©v hasonl√≥ idŇĎszak√°nak √°tlag√°r√°hoz viszony√≠tva. Magyarorsz√°gon a v√°g√≥csirke √©lŇĎs√ļlyos termelŇĎi √°ra (245,9 forint/kilogramm) 4,3 sz√°zal√©kkal volt alacsonyabb 2017 20. het√©ben az egy √©vvel kor√°bbin√°l

    Impact of Vitamin D Supplementation on Arterial Vasomotion, Stiffness and Endothelial Biomarkers in Chronic Kidney Disease Patients

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    Background: Cardiovascular events are frequent and vascular endothelial function is abnormal in patients with chronic kidney disease (CKD). We demonstrated endothelial dysfunction with vitamin D deficiency in CKD patients; however the impact of cholecalciferol supplementation on vascular stiffness and vasomotor function, endothelial and bone biomarkers in CKD patients with low 25-hydroxy vitamin D [25(OH)D] is unknown, which this study investigated. Methods: We assessed non-diabetic patients with CKD stage 3/4, age 17‚Äď80 years and serum 25(OH)D ,75 nmol/L. Brachial artery Flow Mediated Dilation (FMD), Pulse Wave Velocity (PWV), Augmentation Index (AI) and circulating blood biomarkers were evaluated at baseline and at 16 weeks. Oral 300,000 units cholecalciferol was administered at baseline and 8-weeks. Results: Clinical characteristics of 26 patients were: age 50614 (mean61SD) years, eGFR 41611 ml/min/1.73 m2, males 73%, dyslipidaemia 36%, smokers 23% and hypertensives 87%. At 16-week serum 25(OH)D and calcium increased (43616 to 84629 nmol/L, p,0.001 and 2.3760.09 to 2.4260.09 mmol/L; p = 0.004, respectively) and parathyroid hormone decreased (10.868.6 to 7.464.4; p = 0.001). FMD improved from 3.163.3% to 6.163.7%, p = 0.001. Endothelial biomarker concentrations decreased: E-Selectin from 566662123 to 525662058 pg/mL; p = 0.032, ICAM-1, 3.4560.01 to 3.1061.04 ng/mL; p = 0.038 and VCAM-1, 54633 to 42633 ng/mL; p = 0.006. eGFR, BP, PWV, AI, hsCRP, von Willebrand factor and Fibroblast Growth Factor-23, remained unchanged. Conclusion: This study demonstrates for the first time improvement of endothelial vasomotor and secretory functions with vitamin D in CKD patients without significant adverse effects on arterial stiffness, serum calcium or FGF-23. Trial Registration: ClinicalTrials.gov NCT0200571

    Controlled 3D-coating of the pores of highly ordered mesoporous antiferromagnetic Co3O4 replicas with ferrimagnetic FexCo3-xO4 nanolayers

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    The controlled filling of the pores of highly ordered mesoporous antiferromagnetic Co3O4 replicas with ferrimagnetic FexCo3-xO4 nanolayers is presented as a proof-of-concept toward the integration of nanosized units in highly ordered, heterostructured 3D architectures. Antiferromagnetic (AFM) Co3O 4 mesostructures are obtained as negative replicas of KIT-6 silica templates, which are subsequently coated with ferrimagnetic (FiM) Fe xCo3-xO4 nanolayers. The tuneable magnetic properties, with a large exchange bias and coercivity, arising from the FiM/AFM interface coupling, confirm the microstructure of this novel two-phase core-shell mesoporous material. The present work demonstrates that ordered functional mesoporous 3D-materials can be successfully infiltrated with other compounds exhibiting additional functionalities yielding highly tuneable, versatile, non-siliceous based nanocomposites

    Economic evaluation of health services costs during pandemic influenza A (H1N1) pdm09 infection in pregnant and non-pregnant women in Spain (2009)

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    Background: The healthcare and socio-economic burden resulting from influenza A (H1N1) pdm09 in Spain was considerable. Our aim was to estimate and compare the management (resource utilization) and economic healthcare impact in an at-risk group of unvaccinated pregnant women with an unvaccinated group of non-pregnant woman of childbearing age (15-44 yr old). Methods: We addressed this question with a longitudinal, observational, multicentre study. Inputs were the require-ments in managing both groups of women. Outcome measures were healthcare costs. Direct healthcare (including medical utilisation, prescriptions of antivirals, medication, diagnostic tests, and hospitalisation) costs and indirect (productivity loss) costs were considered. Unit of cost was attributed to the frequency of health service resources utili-sation. The mean cost per patient was calculated in this group of women. Results: We found that the influenza clinical pattern was worse in non-pregnant women as they had a high medical risk of 20.4% versus 6.1% of pregnant women. Non-pregnant required more antipyretics and antibiotics, and needed more health service resource utilisation (338 medical visits in non-pregnant women vs. 42 in pregnant women). The total cost of non-pregnant women was higher ( 4,689.4/non-pregnant and 2,945.07/pregnant). Conclusions: Cost per (H1N1) pdm09 was lower for pregnant women, probably due to more preventive measures adopted for their protection in Spain. The highest costs were incurred by hospitalisations/day and work absenteeism for non-pregnant than for pregnant women. These data will allow better future pandemic influenza planning
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