Publications by authors named "Vicent J"

Given the global urgency to mitigate climate change, a key action is the development of effective carbon concentration reduction policies. To this end, an influential factor is the availability of accurate predictions of carbon concentration trends. The existing spatiotemporal correlation as well as the diversity of influential factors, pose important challenges in accurately modeling these trends.

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Controlling the magnetic ground states at the nanoscale is a long-standing basic research problem and an important issue in magnetic storage technologies. Here, we designed a nanostructured material that exhibits very unusual hysteresis loops due to a transition between vortex and double pole states. Arrays of 700 nm diamond-shaped nanodots consisting of Py(30 nm)/Ru()/Py(30 nm) (Py, permalloy (NiFe)) trilayers were fabricated by interference lithography and e-beam evaporation.

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Ratchet devices allow turning an ac input signal into a dc output signal. A ratchet device is set by moving particles driven by zero averages forces on asymmetric potentials. Hybrid nanostructures combining artificially fabricated spin ice nanomagnet arrays with superconducting films have been identified as a good choice to develop ratchet nanodevices.

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In support of cropland monitoring, operational Copernicus Sentinel-2 (S2) data became available globally and can be explored for the retrieval of important crop traits. Based on a hybrid workflow, retrieval models for six essential biochemical and biophysical crop traits were developed for both S2 bottom-of-atmosphere (BOA) L2A and S2 top-of-atmosphere (TOA) L1C data. A variational heteroscedastic Gaussian process regression (VHGPR) algorithm was trained with simulations generated by the combined leaf-canopy reflectance model PROSAILat the BOA scale and further combined with the Second Simulation of a Satellite Signal in the Solar Spectrum (6SV) atmosphere model at the TOA scale.

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Drawing on the recent advances in complex network theory, urban mobility flow patterns, typically encoded as origin-destination (OD) matrices, can be represented as weighted directed graphs, with nodes denoting city locations and weighted edges the number of trips between them. Such a graph can further be augmented by node attributes denoting the various socio-economic characteristics at a particular location in the city. In this paper, we study the spatio-temporal characteristics of "hotspots" of different types of socio-economic activities as characterized by recently developed attribute-augmented network centrality measures within the urban OD network.

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Retrieval of vegetation properties from satellite and airborne optical data usually takes place after atmospheric correction, yet it is also possible to develop retrieval algorithms directly from top-of-atmosphere (TOA) radiance data. One of the key vegetation variables that can be retrieved from at-sensor TOA radiance data is leaf area index (LAI) if algorithms account for variability in atmosphere. We demonstrate the feasibility of LAI retrieval from Sentinel-2 (S2) TOA radiance data (L1C product) in a hybrid machine learning framework.

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Little-Parks effect names the oscillations in the superconducting critical temperature as a function of the magnetic field. This effect is related to the geometry of the sample. In this work, we show that this effect can be enhanced and manipulated by the inclusion of magnetic nanostructures with perpendicular magnetization.

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Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth's atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks used to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires good knowledge of the model inputs/outputs and the generation of large databases of consistent simulations.

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Knowledge of key variables driving the top of the atmosphere (TOA) radiance over a vegetated surface is an important step to derive biophysical variables from TOA radiance data, e.g., as observed by an optical satellite.

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We have designed, fabricated and tested a robust superconducting ratchet device based on topologically frustrated spin ice nanomagnets. The device is made of a magnetic Co honeycomb array embedded in a superconducting Nb film. This device is based on three simple mechanisms: (i) the topology of the Co honeycomb array frustrates in-plane magnetic configurations in the array yielding a distribution of magnetic charges which can be ordered or disordered with in-plane magnetic fields, following spin ice rules; (ii) the local vertex magnetization, which consists of a magnetic half vortex with two charged magnetic Néel walls; (iii) the interaction between superconducting vortices and the asymmetric potentials provided by the Néel walls.

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Collection of spectroradiometric measurements with associated biophysical variables is an essential part of the development and validation of optical remote sensing vegetation products. However, their quality can only be assessed in the subsequent analysis, and often there is a need for collecting extra data, e.g.

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Computationally expensive radiative transfer models (RTMs) are widely used to realistically reproduce the light interaction with the earth surface and atmosphere. Because these models take long processing time, the common practice is to first generate a sparse look-up table (LUT) and then make use of interpolation methods to sample the multidimensional LUT input variable space. However, the question arise whether common interpolation methodsperform most accurate.

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Estimates of Sun-Induced vegetation chlorophyll Fluorescence (SIF) using remote sensing techniques are commonly determined by exploiting solar and/or telluric absorption features. When SIF is retrieved in the strong oxygen (O) absorption features, atmospheric effects must always be compensated. Whereas correction of atmospheric effects is a standard airborne or satellite data processing step, there is no consensus regarding whether it is required for SIF proximal-sensing measurements nor what is the best strategy to be followed.

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We have studied two nanomagnet systems with strong (Co/Pd multilayers) and weak (NdCo alloy films) stray magnetic fields by probing the out-of-plane magnetic states with superconducting vortices. The hybrid samples are made of array of nanomagnets embedded in superconducting Nb thin films. The vortex motion detects relevant magnetic state features, since superconducting vortices are able to discriminate between different magnetic stray field strengths and directions.

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This paper analyzes success public spaces (specifically ) in the urban fabric of the city of Murcia, Spain. Two approaches were adopted. Firstly, the city was visualized as a complex network whose nodes represent .

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We present a simple nanodevice that can operate in two modes: i) non-volatile three-state memory and ii) reading device. The nanodevice can retain three well defined states -1, 0 and +1 and can operate in a second mode as a sensor for external magnetic fields. The nanodevice is fabricated with an array of ordered triangular-shaped nanomagnets embedded in a superconducting thin film gown on Si substrates.

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To develop a full understanding of interactions in nanomagnet arrays is a persistent challenge, critically impacting their technological acceptance. This paper reports the experimental, numerical and analytical investigation of interactions in arrays of Co nanoellipses using the first-order reversal curve (FORC) technique. A mean-field analysis has revealed the physical mechanisms giving rise to all of the observed features: a shift of the non-interacting FORC-ridge at the low-HC end off the local coercivity HC axis; a stretch of the FORC-ridge at the high-HC end without shifting it off the HC axis; and a formation of a tilted edge connected to the ridge at the low-HC end.

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Two rectification mechanisms in vortex lattice dynamics in Nb films have been studied. These two effects are based on ratchet effects, that is, an ac driving force induces a net dc vortex flow. In our case, an input ac current applied to the Nb films, grown on top of arrays of Ni nanotriangles, yields an output dc voltage.

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The magnetization states in Ni triangular dots under an applied magnetic field have been studied using variable-field magnetic force microscopy (VF-MFM) imaging. In order to understand their dynamics we performed micromagnetic simulations which are in remarkable agreement with the experimental MFM results. The nanostructures present magnetic vortices as ground states which move under an external magnetic field.

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The purpose of this phase II trial was to determine the efficacy and safety of the XELOX (capecitabine/oxaliplatin) regimen as first-line therapy in the elderly patients with metastatic colorectal cancer (MCRC). A total of 50 patients with MCRC aged > or = 70 years received oxaliplatin 130 mg m(-2) on day 1 followed by oral capecitabine 1000 mg m(-2) twice daily on days 1-14 every 3 weeks. Patients with creatinine clearance 30-50 ml min(-1) received a reduced dose of capecitabine (750 mg m(-2) twice daily).

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Purpose: Elderly patients constitute a subpopulation with special characteristics that differ from those of the nonelderly and have been underrepresented in clinical trials. This study was performed to determine the efficacy and safety of irinotecan (CPT-11) in combination with fluorouracil (FU) administered as a 48-hour continuous infusion twice a month in elderly patients.

Patients And Methods: Patients > or = 72 years old with metastatic colorectal cancer, Eastern Cooperative Oncology Group performance status of 0 to 1, no geriatric syndromes, and no prior treatment were treated every 2 weeks with CPT-11 180 mg/m2 plus FU 3,000 mg/m2 in a 48-hour continuous infusion.

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Purpose: To determine the tolerability of capecitabine in elderly patients with advanced colorectal cancer (CRC).

Patients And Methods: Fifty-one patients with advanced CRC who were >/= 70 years and considered ineligible for combination chemotherapy received oral capecitabine 1,250 mg/m(2) twice daily on days 1 to 14 every 3 weeks. Patients with a creatinine clearance of 30 to 50 mL/min received a dose of 950 mg/m(2) twice daily.

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Objectives: The combination of irinotecan and raltitrexed is safe and active in 5-fluorouracil-refractory, metastatic colorectal cancer (CRC), with the advantage of its convenient three-weekly schedule. The aim of this multicenter phase II study was to assess its efficacy and toxicity in first-line treatment.

Methods: Between May 2000 and March 2001, 62 previously untreated patients received irinotecan (350 mg/m(2)) plus raltitrexed (3 mg/m(2)), with courses repeated every 21 days.

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The purpose of this study was to evaluate the efficacy, assessed as response rate, and toxicity of UFT (Tegafur-Uracil) in combination with oxaliplatin as first-line treatment of advanced colorectal cancer (CRC). In all, 84 patients with recurrent or metastatic CRC with measurable disease were included. Treatment consisted of oxaliplatin 85 mg m(-2) in 120-min intravenous (i.

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Objective: We present our experience with outpatient tonsillectomy in children and critically review safety to support the outpatient policy.

Study Design And Setting: We conducted a retrospective chart review from January 1995 through December 2000 in the pediatric otolaryngology unit of a tertiary care university hospital.

Results: One thousand two hundred forty-three patients were accepted in the outpatient program with permissive criteria.

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