1,078 research outputs found
Resiliencia de la cubierta vegetal en un área de montaña mediterránea afectada por el fuego: el caso del incendio de Río Verde (provincia de Málaga, sur de España)
The study aim is the comparison of the vegetation cover type before and 22-years after a wildfire in order to evaluate its post-fire resilience as well as the effect of topographic attributes. The study area is that affected by a wildfire in 1991 (Río Verde, Sierra de las Nieves). By means of remote sensing and mapping techniques, the type of vegetation cover was obtained for 1991, just before the wildfire, and for 2013. The comparison of both years indicates 50% of the burned area recovered the pre-fire vegetation cover, while 1/3 presented a major vegetation cover and a type of cover more evolved. Generally speaking, after the wildfire, the most influential topographic features in the vegetal cover evolution were slope gradient, altitude and radiationEl propósito de este estudio es comparar el tipo de cubierta vegetal antes de un incendio y varios años después para evaluar su resiliencia post-incendio, así como la influencia de ciertos atributos topográficos. El área de estudio es el área afectada por el incendio de río Verde, en 1991 (Sierra de las Nieves), con una orografía muy abrupta. Mediante el tratamiento y análisis de imágenes de satélite y posterior procesamiento cartográfico en un SIG, se obtuvieron los tipos de cubierta vegetal en 1991, justo antes del incendio, y en 2013. De la comparación de ambos años, puede decirse que, tras 22 años desde el incendio, la mitad del área quemada ha recuperado la cubierta vegetal previa y 1/3 de la misma presenta actualmente una cubierta vegetal superior, con un tipo de cubierta que evidencia un estado evolutivo más avanzado respecto al determinado antes del incendio. En general, los atributos topográficos que más influyeron en la evolución post-incendio de la cubierta vegetal fueron, en este orden, pendiente, altitud y radiación
Relationship of runoff, erosion and sediment yield to weather types in the Iberian Peninsula
Precipitation has been recognized as one of the main factors driving soil erosion and sediment yield (SY), and its spatial and temporal variability is recognized as one of themain reasons for spatial and temporal analyses of soil erosion variability. The weather types (WTs) approach classifies the continuumof atmospheric circulation into a small number of categories or types and has been proven a good indicator of the spatial and temporal variability of precipitation. Thus, themain objective of this study is to analyze the relationship betweenWTs, runoff, soil erosion (measured in plots), and sediment yield (measured in catchments) in different areas of the Iberian Peninsula (IP) with the aimof detecting spatial variations in these relationships. To this end, hydrological and sediment information covering the IP from several Spanish research teams has been combined, and related with daily WTs estimated by using the NMC/NCAR 40-Year Reanalysis Project. The results showthat, in general, a fewWTs (particularly westerly, southwesterly and cyclonic) provide the largest amounts of precipitation; and southwesterly, northwesterly and westerly WTs play an important role in runoff generation, erosion and sediment yield as they coincide with the wettest WTs. However, this study highlights the spatial variability of erosion and sediment yield in the IP according to WT, differentiating (1) areas under the influence of north and/or north-westerly flows (the north coast of Cantabria and inland central areas), (2) areas under the influence of westerly, southwesterly and cyclonic WTs (western and southwestern IP), (3) areas in which erosion and sediment yield are controlled by easterly flows (Mediterranean coastland), and (4) lastly, a transitional zone in the inland northeast Ebro catchment,wherewe detected a high variability in the effects ofWTs on erosion. Overall results suggest that the use of WTs derived fromobserved atmospheric pressure patterns could be a useful tool for inclusion in future projections of the spatial variability of erosion and sediment yield, as models capture pressure fields reliably
Chromosomal instability in aneuploid acute lymphoblastic leukemia associates with disease progression
Chromosomal instability (CIN) lies at the core of cancer development leading to aneuploidy, chromosomal copy-number heterogeneity (chr-CNH) and ultimately, unfavorable clinical outcomes. Despite its ubiquity in cancer, the presence of CIN in childhood B-cell acute lymphoblastic leukemia (cB-ALL), the most frequent pediatric cancer showing high frequencies of aneuploidy, remains unknown. Here, we elucidate the presence of CIN in aneuploid cB-ALL subtypes using single-cell whole-genome sequencing of primary cB-ALL samples and by generating and functionally characterizing patient-derived xenograft models (cB-ALL-PDX). We report higher rates of CIN across aneuploid than in euploid cB-ALL that strongly correlate with intraclonal chr-CNH and overall survival in mice. This association was further supported by in silico mathematical modeling. Moreover, mass-spectrometry analyses of cB-ALL-PDX revealed a "CIN signature" enriched in mitotic-spindle regulatory pathways, which was confirmed by RNA-sequencing of a large cohort of cB-ALL samples. The link between the presence of CIN in aneuploid cB-ALL and disease progression opens new possibilities for patient stratification and offers a promising new avenue as a therapeutic target in cB-ALL treatment.</p
Linear chaos for the Quick-Thinking-Driver model
The final publication is available at Springer via http://dx.doi.org/10.1007/s00233-015-9704-6In recent years, the topic of car-following has experimented an increased importance in traffic engineering and safety research. This has become a very interesting topic because of the development of driverless cars (Google driverless cars, http://en.wikipedia.org/wiki/Google_driverless_car).Driving models which describe the interaction between adjacent vehicles in the same lane have a big interest in simulation modeling, such as the Quick-Thinking-Driver model. A non-linear version of it can be given using the logistic map, and then chaos appears. We show that an infinite-dimensional version of the linear model presents a chaotic behaviour using the same approach as for studying chaos of death models of cell growth.The authors were supported by a grant from the FPU program of MEC and MEC Project MTM2013-47093-P.Conejero, JA.; Murillo Arcila, M.; Seoane-Sepúlveda, JB. (2016). Linear chaos for the Quick-Thinking-Driver model. Semigroup Forum. 92(2):486-493. https://doi.org/10.1007/s00233-015-9704-6S486493922Aroza, J., Peris, A.: Chaotic behaviour of birth-and-death models with proliferation. J. Differ. Equ. Appl. 18(4), 647–655 (2012)Banasiak, J., Lachowicz, M.: Chaos for a class of linear kinetic models. C. R. Acad. Sci. Paris Série II 329, 439–444 (2001)Banasiak, J., Lachowicz, M.: Topological chaos for birth-and-death-type models with proliferation. Math. Models Methods Appl. Sci. 12(6), 755–775 (2002)Banasiak, J., Lachowicz, M., Moszyński, M.: Topological chaos: when topology meets medicine. Appl. Math. Lett. 16(3), 303–308 (2003)Banasiak, J., Moszyński, M.: A generalization of Desch–Schappacher–Webb criteria for chaos. Discret. Contin. Dyn. Syst. 12(5), 959–972 (2005)Banasiak, J., Moszyński, M.: Dynamics of birth-and-death processes with proliferation–stability and chaos. Discret. Contin. Dyn. 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Massachusetts Institute of Technology. Cambridge (1973)CNN (2014) Driverless car tech gets serious at CES. http://edition.cnn.com/2014/01/09/tech/innovation/self-driving-cars-ces/ . Accessed 7 Apr 2014Conejero, J.A., Rodenas, F., Trujillo, M.: Chaos for the hyperbolic bioheat equation. Discret. Contin. Dyn. Syst. 35(2), 653–668 (2015)DARPA Grand Challenge. http://en.wikipedia.org/wiki/2005_DARPA_Grand_Challenge#2005_Grand_Challengede Laubenfels, R., Emamirad, H., Protopopescu, V.: Linear chaos and approximation. J. Approx. Theory 105(1), 176–187 (2000)Desch, W., Schappacher, W., Webb, G.F.: Hypercyclic and chaotic semigroups of linear operators. Ergod. Theory Dyn. Syst. 17(4), 793–819 (1997)El Mourchid, S.: The imaginary point spectrum and hypercyclicity. Semigroup Forum 73(2), 313–316 (2006)El Mourchid, S., Metafune, G., Rhandi, A., Voigt, J.: On the chaotic behaviour of size structured cell populations. J. Math. Anal. 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Evaluating the extent and impact of the extreme Storm Gloria on Posidonia oceanica seagrass meadows
Extreme storms can trigger abrupt and often lasting changes in ecosystems by affecting foundational (habitat-forming) species. While the frequency and intensity of extreme events are projected to increase under climate change, its impacts on seagrass ecosystems remain poorly documented. In January 2020, the Spanish Mediterranean coast was hit by Storm Gloria, one of the most devastating recent climate events in terms of intensity and duration. We conducted rapid surveys of 42 Posidonia oceanica meadows across the region to evaluate the extent and type of impact (burial, unburial and uprooting). We investigated the significance of oceanographic (wave impact model), geomorphological (latitude, depth, exposure), and structural (patchiness) factors in predicting impact extent and intensity. The predominant impact of Storm Gloria was shoot unburial. More than half of the surveyed sites revealed recent unburial, with up to 40 cm of sediment removed, affecting over 50 % of the meadow. Burial, although less extensive, was still significant, with 10–80 % of meadow cover being buried under 7 cm of sediment, which is considered a survival threshold for P. oceanica. In addition, we observed evident signs of recently dead matte in some meadows and large amounts of detached drifting shoots on the sea bottom or accumulated as debris on the beaches. Crucially, exposed and patchy meadows were much more vulnerable to the overall impact than sheltered or continuous meadows. Given how slow P. oceanica is able to recover after disturbances, we state that it could take from decades to centuries for it to recoup its losses. Seagrass ecosystems play a vital role as coastal ecological infrastructure. Protecting vulnerable meadows from anthropogenic fragmentation is crucial for ensuring the resilience of these ecosystems in the face of the climate crisis.This study was funded by the CSIC project “Effects of storm Gloria on the western Mediterranean meadows (202030E052) and “Storms of change: as phenomena extreme weather alters Mediterranean coastal ecosystems, their services and their perception by society" (PID2020-113745RB-I00), state program of I+D+I Oriented to the Challenges of the Society and within the framework of the activities of the Spanish Government through the "Maria de Maeztu Centre of Excellence” accreditation to IMEDEA (CSIC-UIB) (CEX2021-001198). We want to thank the SPAS (Society of Fishing and Underwater Activities of Mataró) and the Mataró City Council, which has financed 25 years of the Alguer de Mataró project
Short-term low-severity spring grassland fire impacts on soil extractable elements and soil ratios in Lithuania.
Spring grassland fires are common in boreal areas as a consequence of slash and burn agriculture used to remove dry grass to increase soil nutrient properties and crop production. However, fewworks have investigated fire impacts on these grassland ecosystems, especially in the immediate period after the fire. The objective of this work was to study the short-termimpacts of a spring grassland fire in Lithuania. Four days after the firewe established a 400 m2 sampling grid within the burned area and in an adjacent unburned area with the same topographical, hydrological and pedological characteristics. Wecollected topsoil samples immediately after the fire (0 months), 2, 5, 7 and 9 months after the fire. We analysed soil pH, electrical conductivity (EC), major nutrients including calcium(Ca), magnesium(Mg), sodium(Na), and potassium(K), and theminor elements aluminium(Al), manganese (Mn), iron (Fe) and zinc (Zn). We also calculated the soil Na and K adsorption ratio (SPAR), Ca:Mg and Ca:Al. The results showed that this low-severity grassland fire significantly decreased soil pH, Al, and Mn but increased EC, Ca,Mg, and K,. There was no effect on Na, Fe, and Zn. Therewas a decrease of EC, Ca,Mg, and Na from 0months after the fire until 7 months after the fire,with an increase during the last sampling period. Fire did not significantly affect SPAR. Ca:Mg decreased significantly immediately after the fire, but not to critical levels. Ca:Al increased after the fire, reducing the potential effects of Al on plants. Overall, fire impactsweremainly limited to the immediate period after the fire
Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study
Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders
CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative
Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research
An embedding technique to determine ττ backgrounds in proton-proton collision data
An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe
Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions
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