221 research outputs found
Partial migration of white-winged snowfinches is correlated with winter weather conditions
No full textThis study was supported by the British Ornithologists' Union, which awarded Jaime Resano-Mayor in 2014 with a “Career Development Bursary”. M.M.D. was financially supported by the (a) Spanish Ministry of Sciences, Innovation and Universities (#CGL2016-79764-P); and (b) a Spanish Ramón y Cajal grant RYC-2014-16263.Resano-Mayor, J., Bettega, C., Delgado, M.D.M., Fernández-Martín, Á., Hernández-Gómez, S., Toranzo, I., España, A., de Gabriel, M., Roa-Álvarez, I., Gil, J.A., Strinella, E., Hobson, K.A., Arlettaz, R
Copper and tin isotopic analysis of ancient bronzes for archaeological investigation : development and validation of a suitable analytical methodology
No full textAlthough in many cases Pb isotopic analysis can be relied on for provenance determination of ancient bronzes, sometimes the use of "non-traditional" isotopic systems, such as those of Cu and Sn, is required. The work reported on in this paper aimed at revising the methodology for Cu and Sn isotope ratio measurements in archaeological bronzes via optimization of the analytical procedures in terms of sample pre-treatment, measurement protocol, precision, and analytical uncertainty. For Cu isotopic analysis, both Zn and Ni were investigated for their merit as internal standard (IS) relied on for mass bias correction. The use of Ni as IS seems to be the most robust approach as Ni is less prone to contamination, has a lower abundance in bronzes and an ionization potential similar to that of Cu, and provides slightly better reproducibility values when applied to NIST SRM 976 Cu isotopic reference material. The possibility of carrying out direct isotopic analysis without prior Cu isolation (with AG-MP-1 anion exchange resin) was investigated by analysis of CRM IARM 91D bronze reference material, synthetic solutions, and archaeological bronzes. Both procedures (Cu isolation/no Cu isolation) provide similar delta Cu-65 results with similar uncertainty budgets in all cases (+/- 0.02-0.04 per mil in delta units, k = 2, n = 4). Direct isotopic analysis of Cu therefore seems feasible, without evidence of spectral interference or matrix-induced effect on the extent of mass bias. For Sn, a separation protocol relying on TRU-Spec anion exchange resin was optimized, providing a recovery close to 100 % without on-column fractionation. Cu was recovered quantitatively together with the bronze matrix with this isolation protocol. Isotopic analysis of this Cu fraction provides delta Cu-65 results similar to those obtained upon isolation using AG-MP-1 resin. This means that Cu and Sn isotopic analysis of bronze alloys can therefore be carried out after a single chromatographic separation using TRU-Spec resin. Tin isotopic analysis was performed relying on Sb as an internal standard used for mass bias correction. The reproducibility over a period of 1 month (n = 42) for the mass bias-corrected Sn isotope ratios is in the range of 0.06-0.16 per mil (2 s), for all the ratios monitored
In between crystalline and transparent. The skyscraper in Friedrichstrasse by Mies Van der Rohe
No full text[EN] Crystalline qualities of glass were very appreciated by Expressionism. Some years later, transparency became a keystone for the Modern Movement. Mies van der Rohe drew his entry for the Friedrichstrasse Competition in 1921, in a moment of transition between both architectonical movements. The aim of this article is to show how the graphic documents made by Mies exemplify this change of tendency. His representation of the glazed enclosure evolves from opaque reflection to a partial transparency that shows the inner structure. This process confirms the importance of structural conception for the architectural form. These drawings show the beginning of a new poetic of transparency, for its author as for Modernism.[ES] Los arquitectos expresionistas apreciaron el simbolismo cristalino del vidrio. Unos años más tarde el Movimiento Moderno ensalzó su transparencia. Mies van der Rohe dibuja su propuesta para el concurso de Rascacielos en la Friedrichstrasse en 1921, en un momento de transición entre ambas corrientes arquitectónicas. El objetivo de este artículo es analizar la documentación gráfica elaborada por Mies como ejemplo de este cambio de tendencia. Su representación del cierre acristalado evoluciona desde el reflejo casi opaco hacia una transparencia parcial que hace visible la estructura interior. Este proceso confirma la importancia de la concepción estructural de la forma arquitectónica. Estos dibujos muestran el principio de una poética de lo trasparente, tanto para su autor como para la arquitectura moderna.Resano Resano, D. (2017). Entre lo cristalino y lo transparente. El rascacielos en la Friedrichstrasse de Mies van der Rohe. EGA. Revista de Expresión Gráfica Arquitectónica. 22(31):132-139. https://doi.org/10.4995/ega.2017.3507SWORD1321392231Drexler, A. & schulze, F. (1986) The Mies van der Rohe Archive, New York, Garland.Neumeyer, F. (1995) The Artless Word: Mies van der Rohe on the Building Art. From the Spanis Edition: La palabra sin artificio, Madrid, El Croquis.Scheerbart, P. (1914) Glassarchitectur. From the edition in Spanish: (1998) La arquitectura de cristal, Murcia Colegio Oficial de Aparejadores y Arquitectos Técnicos.Taut, B. (1922a) without tittle. Frühlicht, 3, 84-85.Taut, B. (1922b) Ludwig Mies van der Rohe. Hochhaus. Frühlicht, 4, 122-124.Tegethoff, W. (1985). The Villas and Country Houses. Nueva York, MOMA
Potential distribution of a climate sensitive species, the White-winged Snowfinch Montifringilla nivalis in Europe
No full textMD was supported by the Spanish Ministry of Sciences, Innovation and Universities (#CGL2016-79764-P) and by a Spanish Ramon y Cajal grant RYC-2014-16263.Brambilla, M., Resano-Mayor, J., Arlettaz, R., Bettega, C., Binggeli, A., Bogliani, G., Braunisch, V., Celada, C., Chamberlain, D.A.N., Chiffard Carricaburu, J., Delgado, M.D.E.L.M.A.R., Fontanilles, P., Kmecl, P., Korner, F., Lindner, R., Pedrini, P., Pöhacker, J., Rubinic, B., Schano, C., Scridel, D., Strinella, E., Teufelbauer, N., De Gabriel Hernando, M
Single Particle Inductively Coupled Plasma Mass Spectrometry (SP-ICP-MS): an innovative approach for inorganic nanoparticles analysis
No full textSimultaneous determination of halogens by high resolution absortion spectrometry
No full textThe high ionization potentials and low wavelength emission lines of halogens difficult the analysis of their organohalogen compounds by ICP-based methods [1]. Other techniques, such as combustion ion chromatography (CIC) or ion-selective electrodes have proven to be more reliable to determine these elements. However, these techniques are more time-consuming and/or have lower precision and accuracy.
High resolution continuum source graphite furnace molecular absorption spectrometry (HR CS GFMAS) allows the determination of solid and liquid samples by monitoring a molecule formed with the analyte and a molecule forming reagent. In the case of F, Cl and Br, several molecule forming agents have been studied for their determination. Among all of them, calcium can form a stable bond with the three elements and provides optimal analytical properties for trace analysis [2]. However, the spectral window of commercially available continuum source AAS instruments is not broad enough to cover the wavelength range necessary for a simultaneous determination. Thus, coupling it with a modular simultaneous echelle spectrograph (MOSES), which can register around 200 nm in a single measure, allows the simultaneous study of the three analytes [3].
This instrumentation is capable of register more than 200 nm of the spectra per measure keeping a high resolution. This spectral window is suitable for the monitorization of a variety of transitions of the three molecules. However, some of them are overlapped and the competitive mechanism of formation of the three molecules modify their sensitivity depending on the proportions in the sample.
In this study, a compromise in the conditions and modifiers were selected in order to maximize the sensitivity and signal to noise ratio for the three molecules. The determination was carried out by standard addition of CaF and Cl and Br were obtained from the PLS model.
References:
[1] X. Bu, T. Wang, G. Hall, J. Anal. At. Spectrom., 18, 1443–1451 (2003)
[2] M. Resano, E. García-Ruiz, M. Aramendía, M. A. Belarra, J. Anal. At. Spectrom., 34, 59–80 (2019)
[3] S. Geisler, M. Okruss, H. Becker-Ross, M. Dong Huang, N. Esser, S. Florek, Spectrochimica Acta PartB, 107, 11–16 (2015
Past and future impact of climate change on foraging habitat suitability in a high-alpine bird species : management options to buffer against global warming effects
No full textThe majority of predictions about the impacts of climate change on wildlife have relied either on the study of species' physiological tolerance or on broad-scale distribution models. In comparison, little attention has been paid to species' mechanistic responses to fine-grained, climate-induced modifications of habitat suitability. However, such studies would be pivotal to the understanding of species' ecological requirements (and hence their adaptive potential to environmental change) and the design of management strategies. We investigated foraging microhabitat selection in a potentially climate-change sensitive species, the white-winged snowfinch Montifringilla nivalis, during the breeding season in the Alps. Our microhabitat selection model considered topography, ground-cover variables and sward height within a 5-m radius at foraging and control locations. Habitat selection was positively affected by grassland cover, negatively by sward height and quadratically by snow cover (optimum around 40%); birds avoided anthropized (urban areas, roads) sites. We estimated past (1976) and future (2066) climate-driven changes in foraging microhabitat suitability, assuming a progressively earlier date of snowmelt due to increasing temperatures over this entire time span. We then modelled the potential impact of snowmelt (and related sward height) on habitat suitability under two scenarios: maintaining the current situation (i.e. irregular seasonal grazing) and implementing targeted management in an attempt to mitigate impacts of earlier snowmelt. Predicted foraging habitat suitability (estimated as the fraction of suitable plots) significantly declined over time (−23% between 1976 and 2016, further 32% loss by 2066). However, model outputs demonstrated that maintaining sward height below 6 cm on breeding grounds (e.g. by regular grazing) would significantly decrease the predicted loss of suitable foraging habitat. Detailed information about patterns of resource exploitation allows the identification of mechanistic, functional responses of species to environmental change, and enables an evaluation of habitat management options that can buffer against the detrimental effects of global warming
Effect of nano- fillers on tensile properties of biopolymer films
No full textThere is a growing interest in biopolymers due to their biodegradability, biocompatibility, and edibility. Biopolymer applications include food packaging, biomedical applications, and as structural materials. However, their mechanical properties are limiting. Current research is focused on modifying the physical and chemical properties of biopolymers for better performance and broader applications. The addition of nanofillers has been proposed as a way to modify mechanical properties of biopolymers. This work is focused on biopolymers as edible materials, therefore biopolymers and fillers must meet this requirement. In this study, microcrystalline cellulose (MCC), nanocrystalline cellulose (CNC), CaCO3 nanoparticles, hydrophilic nanoclay and hydrophobic nanoclay were separately added as fillers to the polymers, konjac glucomannan (KGM), hydroxypropyl methylcellulose (HPMC), and zein to investigate their effect on tensile properties of composite films. Tensile properties were measured by dynamic mechanical analysis (DMA) obtaining stress (σ), strain (γ), and Young’s modulus (E). Results revealed significant differences between neat polymers. Fillers, at 2% w/w, affected film properties depending on their size, shape, and surface chemistry. Good dispersibility and the extent of polymer-filler interactions controlled the effect of nanofillers on film properties. Nano-size, high aspect ratio, and hydrophilicity showed significant effects on tensile properties over micro-size, low aspect ratio, and hydrophobic fillers. Hydrophilic nanoclay and CNC interacted better with biopolymer matrices than hydrophobic nanoclay, MCC, or CaCO3. The load limit of CNC in KGM and HPMC to increase σ of neat polymers was 2% and 4%, respectively. Further addition resulted in γ and σ decrement. Load differences were attributed to differences in microstructure between KGM and HPMC. Addition of CNC up to 50% w/w resulted in a higher value of E, suggesting a volume fraction effect of nanocomposite components on films properties. The conclusions of this study were that the addition of nanofillers to biopolymers can lead to reinforced composites if there is good interaction between filler and matrix. Nanocomposite technology offers to broaden the application of biopolymers through the design of new materials with competitive mechanical, thermal, and barrier properties.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2018-12-01The student, Ines Resano Goizueta, accepted the attached license on 2016-12-02 at 10:14.The student, Ines Resano Goizueta, submitted this Thesis for approval on 2016-12-02 at 11:28.This Thesis was approved for publication on 2016-12-09 at 13:36.DSpace SAF Submission Ingestion Package generated from Vireo submission #10415 on 2021-09-16 at 20:06:29Made available in DSpace on 2021-09-17T04:03:52Z (GMT). No. of bitstreams: 2
RESANOGOIZUETA-THESIS-2016.pdf: 2513126 bytes, checksum: 6a49e7afd225504d27af1036b8d4fd33 (MD5)
LICENSE.txt: 4217 bytes, checksum: 0b853838e3c6e32b98146090c74b2a5f (MD5)
Previous issue date: 2016-12-09Embargo set by: Seth Robbins for item 118607
Lift date: 2023-09-17T04:04:53Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 118607
Lift date: 2023-09-17T04:07:01Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemAuthor requested closed access (OA after 2yrs) in Vireo ETD systemLimite
Impact of COPD in patients with lung cancer and advanced disease treated with chemotherapy and/or tyrosine kinase inhibitors
No full textJosé Luis Izquierdo, Pilar Resano, Abdulkader El Hachem, Desiré Graziani, Carlos Almonacid, Ignacio M Sánchez Pulmonology Department, Guadalajara University Hospital, Guadalajara, Spain Abstract: While it is relatively well known that the prognosis of patients with lung cancer (LC) treated with surgery is worse in the presence of chronic obstructive pulmonary disease (COPD), it is unknown if this assessment can be extrapolated to patients with advanced disease treated with chemotherapy and/or tyrosine kinase inhibitors. The aim of our study is to analyze the clinical characteristics and survival rates in patients with LC and COPD, and to compare these to the patients without airflow obstruction. From 471 evaluable patients, 324 (69%) were not treated with surgery due to disseminated disease (stages 3B and 4). Of them, 47.7% also had COPD. All patients were treated at the moment of diagnosis according to National Comprehensive Cancer Network guidelines with platinum-based chemotherapy or tyrosine kinase inhibitors. Kaplan–Meier curves showed no significant differences in overall survival between COPD and non-COPD patients (log–rank P=0.65). In the multivariate Cox proportional hazard model adjusting for the most relevant variables, the adjusted hazard ratio (HRadj) was statistically significant for performance status (HRadj =1.33, 95% confidence interval [CI]: 1.11–1.59; P=0.002) and clinical stage (HRadj =0.67, 95% CI: 0.50–0.89; P=0.006), but not for COPD status (HRadj =1.20, 95% CI: 0.83–1.50; P=0.46). Our conclusion is that at present, when using standard care in advanced LC (stages 3B and 4), COPD does not have a significant deleterious impact on overall survival. Keywords: lung cancer, chronic obstructive pulmonary disease, extended disease, chemotherapy, surviva
Spatio-temporal variation in the wintering associations of an alpine bird
No full textM.d.M.D. was financially supported by the (i) Spanish Ministry of Sciences, Innovation and Universities (no. CGL2016-79764-P)
and (ii) a Spanish Ramón y Cajal grant no. RYC-2014-16263. M.B.
was partly supported by the project Mediterranean Mosaics II
funded by MAVA to Lipu.Delgado Sánchez, M. M.; Arlettaz, R.; Bettega, C.; Brambilla, M.; Hernando, M. de G.; España, A.; Fernández González, Á.; Fernández Martín, Á.; Gil, J. A.; Hernández Gómez, S.; Laiolo, P.; Resano Mayor, J.; Obeso Suárez, J. R.; Pedrini, P.; Roa-Álvarez, I.; Schano, C.; Scridel, D.; Strinella, E.; Toranzo, I.; Korner-Nievergelt, F
- …
