Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) can form multiprotein complexes (heteromers), which can alter the pharmacology and functions of the constituent receptors. Previous findings... more
Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) can form multiprotein complexes (heteromers), which can alter the pharmacology and functions of the constituent receptors. Previous findings demonstrated that the Gq/11-coupled serotonin 5-HT2A receptor and the Gi/o-coupled metabotropic glutamate 2 (mGlu2) receptor-GPCRs that are involved in signaling alterations associated with psychosis-assemble into a heteromeric complex in the mammalian brain. In single-cell experiments with various mutant versions of the mGlu2 receptor, we showed that stimulation of cells expressing mGlu2-5-HT2A heteromers with an mGlu2 agonist led to activation of Gq/11 proteins by the 5-HT2A receptors. For this crosstalk to occur, one of the mGlu2 subunits had to couple to Gi/o proteins, and we determined the relative location of the Gi/o-contacting subunit within the mGlu2 homodimer of the heteromeric complex. Additionally, mGlu2-dependent activation of Gq/11, but not Gi/...
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We previously reported that co-expression of the Gi-coupled metabotropic glutamate receptor 2 (mGlu2R) and the Gq-coupled serotonin (5-HT) 2A receptor (2AR) in Xenopus oocytes (Fribourg et al. Cell 147:1011-1023, 2011) results in inverse... more
We previously reported that co-expression of the Gi-coupled metabotropic glutamate receptor 2 (mGlu2R) and the Gq-coupled serotonin (5-HT) 2A receptor (2AR) in Xenopus oocytes (Fribourg et al. Cell 147:1011-1023, 2011) results in inverse cross-signaling, where for either receptor, strong agonists suppress and inverse agonists potentiate the signaling of the partner receptor. Importantly, through this cross-signaling, the mGlu2R/2AR heteromer integrates the actions of psychedelic and antipsychotic drugs. To investigate whether mGlu2R and 2AR can cross-signal in mammalian cells, we stably co-expressed them in HEK293 cells along with the GIRK1/GIRK4 channel, a reporter of Gi and Gq signaling activity. Crosstalk-positive clones were identified by Fura-2 calcium imaging, based on potentiation of 5-HT-induced Ca(2+) responses by the inverse mGlu2/3R agonist LY341495. Cross-signaling from both sides of the complex was confirmed in representative clones by using the GIRK channel reporter, b...
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... ENVISAT/MERIS and PROBA/CHRIS Sensors Luis Gómez-Chova ∗ , Gustavo Camps-Valls ∗ , Julia Amorós-López ∗ , Luis Guanter , ... Page 4. Fig. 3. Results on a MERIS image over France (snowy mountains from south to east: Pyrenees, Massif... more
... ENVISAT/MERIS and PROBA/CHRIS Sensors Luis Gómez-Chova ∗ , Gustavo Camps-Valls ∗ , Julia Amorós-López ∗ , Luis Guanter , ... Page 4. Fig. 3. Results on a MERIS image over France (snowy mountains from south to east: Pyrenees, Massif Central, and Alps). ...
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ABSTRACT
The Compact High Resolution Imaging Spectrometer (CHRIS) on board the Project for On–Board Autonomy (PROBA) platform system provides the first high spa-tial resolution hyperspectral/multiangular remote sensing data from a satellite... more
The Compact High Resolution Imaging Spectrometer (CHRIS) on board the Project for On–Board Autonomy (PROBA) platform system provides the first high spa-tial resolution hyperspectral/multiangular remote sensing data from a satellite system, what represents a new source of information for Earth Observation purposes. When dealing with the retrieval of surface reflectance from such kind of hyperspectral data, a radiative transfer approach is commonly preferred. However, since CHRIS 2003 and 2004 data present reported calibration problems in several bands, especially in the near–infrared region, a standard atmospheric correction based on radiative trans-fer models should not be performed. A dedicated at-mospheric correction algorithm for CHRIS/PROBA data over land is presented in this work. It consists in the combination of radiative transfer and empirical line ap-proaches to atmospheric correction, in order to retrieve surface reflectance images free from both the atmo-spheric distortio...
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ABSTRACT This study provides insight into the key variables that drive sun-induced chlorophyll fluorescence (SIF) emanating from vegetation canopies, based on a global sensitivity analysis (GSA) of the Soil-Canopy Observation of... more
ABSTRACT This study provides insight into the key variables that drive sun-induced chlorophyll fluorescence (SIF) emanating from vegetation canopies, based on a global sensitivity analysis (GSA) of the Soil-Canopy Observation of Photosynthesis and Energy (SCOPE) balance model. An updated version of the SCOPE model was used here (v1.53) which contains novel leaf physiological modules for determination of the steady state fluorescence yield: a photosynthesis model coupled with (a) submodels having empirically derived relationships, identified as TB12 for unstressed and TB12-D for drought conditions and (b) a mechanistic (MD12) submodel based on theoretical relationships. By inspecting Sobol's total order (main effect and all the interactions) sensitivity index (STi) rankings, the influential and non-influential variables were determined. Two experiments were conducted for the different leaf physiology modules in SCOPE considering (1) only vegetation variables, and (2) all SCOPE variables, i.e., including micrometeorological, aerodynamic and geometry variables.
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CREAF elaborates the cartography of Catalonia in the project SIOSE (Information System on Land Use in Spain). In the Catalan area, this cartography is obtained from the Land Cover Map of Catalonia (MCSC), in its third edition. These two... more
CREAF elaborates the cartography of Catalonia in the project SIOSE (Information System on Land Use in Spain). In the Catalan area, this cartography is obtained from the Land Cover Map of Catalonia (MCSC), in its third edition. These two maps have their own characteristics as for legend and base images. However, their greatest differences are related to the scale of
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Nickel pollution may affect microbial communitydevelopment and its activity in soil and, therefore, itsfertility, while organic amendment may affect Ni mobilityand bioavailability. The aim of this research was toascertain the extent to... more
Nickel pollution may affect microbial communitydevelopment and its activity in soil and, therefore, itsfertility, while organic amendment may affect Ni mobilityand bioavailability. The aim of this research was toascertain the extent to which the addition of sewage sludgeto soil may affect Ni toxicity and to establish theecological dose of this heavy metal. Unamended and amendedsoils with sewage sludge were spiked
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The monitoring of the carbon stock in terrestrial environments, as well as the improved understanding of the surface-atmosphere interactions controlling the exchange of matter, energy and momentum, is of immediate interest for an improved... more
The monitoring of the carbon stock in terrestrial environments, as well as the improved understanding of the surface-atmosphere interactions controlling the exchange of matter, energy and momentum, is of immediate interest for an improved assessment of the various components of the global carbon cycle. Studies of the Earth System processes at the global scale rely on models that require an
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The Compact High Resolution Imaging Spectrometer (CHRIS) on board the Project for On-Board Autonomy (PROBA) platform system provides the first high spa- tial resolution hyperspectral/multiangular remote sensing data from a satellite... more
The Compact High Resolution Imaging Spectrometer (CHRIS) on board the Project for On-Board Autonomy (PROBA) platform system provides the first high spa- tial resolution hyperspectral/multiangular remote sensing data from a satellite system, what represents a new source of information for Earth Observation purposes. When dealing with the retrieval of surface reflectance from such kind of hyperspectral data, a radiative transfer
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ABSTRACT Biophysical parameters such as leaf chlorophyll content (LCC) and leaf area index (LAI) are standard vegetation products that can be retrieved from Earth observation imagery. This paper introduces a new machine learning... more
ABSTRACT Biophysical parameters such as leaf chlorophyll content (LCC) and leaf area index (LAI) are standard vegetation products that can be retrieved from Earth observation imagery. This paper introduces a new machine learning regression algorithms (MLRAs) toolbox into the scientific Automated Radiative Transfer Models Operator (ARTMO) software package. ARTMO facilitates retrieval of biophysical parameters from remote observations in a MATLAB graphical user interface (GUI) environment. The MLRA toolbox enables analyzing the predictive power of various MLRAs in a semiautomatic and systematic manner, and applying a selected MLRA to multispectral or hyperspectral imagery for mapping applications. It contains both linear and nonlinear state-of-the-art regression algorithms, in particular linear feature extraction via principal component regression (PCR), partial least squares regression (PLSR), decision trees (DTs), neural networks (NNs), kernel ridge regression (KRR), and Gaussian processes regression (GPR). The performance of multiple implemented regression strategies has been evaluated against the SPARC dataset (Barrax, Spain) and simulated Sentinel-2 (8 bands), CHRIS (62 bands) and HyMap (125 bands) observations. In general, nonlinear regression algorithms (NN, KRR, and GPR) outperformed linear techniques (PCR and PLSR) in terms of accuracy, bias, and robustness. Most robust results along gradients of training/validation partitioning and noise variance were obtained by KRR while GPR delivered most accurate estimations. We applied a GPR model to a hyperspectral HyMap flightline to map LCC and LAI. We exploited the associated uncertainty intervals to gain insight in the per-pixel performance of the model.
Epidemiological studies indicate that maternal influenza viral infection increases the risk for schizophrenia in the adult offspring. The serotonin and glutamate systems are suspected in the etiology of schizophrenia, as well as in the... more
Epidemiological studies indicate that maternal influenza viral infection increases the risk for schizophrenia in the adult offspring. The serotonin and glutamate systems are suspected in the etiology of schizophrenia, as well as in the mechanism of action of antipsychotic drugs. The effects of hallucinogens, such as psilocybin and mescaline, require the serotonin 5-HT(2A) receptor, and induce schizophrenia-like psychosis in humans. In addition, metabotropic glutamate receptor mGlu(2/3) agonists show promise as a new treatment for schizophrenia. Here, we investigated the level of expression and behavioral function of 5-HT(2A) and mGlu(2) receptors in a mouse model of maternal influenza viral infection. We show that spontaneous locomotor activity is diminished by maternal infection with the mouse-adapted influenza A/WSN/33 (H1N1) virus. The behavioral responses to hallucinogens and glutamate antipsychotics are both affected by maternal exposure to influenza virus, with increased head-...
Research Interests: Neuroscience, Schizophrenia, Pregnancy, Cerebral Cortex, Mice, and 15 moreFemale, Animals, Metabotropic Glutamate Receptors, The, Hallucinogens, Neural pathways, Frontal Lobe, Glutamic Acid, Maternal-fetal exchange, Orthomyxoviridae Infections, Adult Children, Down-Regulation, Antipsychotic agents, Psychology and Cognitive Sciences, and Medical and Health Sciences
G protein-coupled receptors (or GPCRs) represent the largest family of membrane proteins in the human genome and are the target of approximately half of all therapeutic drugs. GPCRs contain a conserved structure of seven transmembrane... more
G protein-coupled receptors (or GPCRs) represent the largest family of membrane proteins in the human genome and are the target of approximately half of all therapeutic drugs. GPCRs contain a conserved structure of seven transmembrane domains. Their amino terminus is located extracellularly, whereas the carboxy terminus extends into the cytoplasm. Accumulating evidence suggests that GPCRs exist and function as monomeric entities. Nevertheless, more recent findings indicate that GPCRs can also form dimers or even higher order oligomers. The differential pharmacological and signaling properties of GPCR heteromeric complexes hint that their physiological effects may be different as compared to those obtained in tissue cultures that express a particular GPCR. In this chapter, we review current data on the role of GPCR heteromerization in receptor signaling, as well as its potential implication in neuropsychiatric disorders such as schizophrenia, depression, and Parkinson's disease.
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Airborne thermal infrared image data at high spatial resolution (2-4 m) acquired with the Airborne Hyperspectral Scanner (AHS) over Barrax (Spain), Görmin (Germany) and Cabauw, Loobos and Speulderbos (The Netherlands) were used to study... more
Airborne thermal infrared image data at high spatial resolution (2-4 m) acquired with the Airborne Hyperspectral Scanner (AHS) over Barrax (Spain), Görmin (Germany) and Cabauw, Loobos and Speulderbos (The Netherlands) were used to study the thermal signatures of land cover types. The processing of the airborne imagery includes atmospheric correction of the AHS thermal infrared (TIR) bands and the retrieval
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... Jose A. Sabrina, Guillem Soria, Juan Carlos Jimenez-Munoz, Belen Franch, Victoria Hidalgo ... Agricultura Sostenible (lAS) Consejo Superior de Investigaciones Cientificas (CSIC), Cordoba, Spain ... wavelength by means of a normalised... more
... Jose A. Sabrina, Guillem Soria, Juan Carlos Jimenez-Munoz, Belen Franch, Victoria Hidalgo ... Agricultura Sostenible (lAS) Consejo Superior de Investigaciones Cientificas (CSIC), Cordoba, Spain ... wavelength by means of a normalised difference index called the Photochemical ...
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Imaging spectrometers operating in the solar spectrum measure the upwelling reflected solar radiation, and are an important tool in the bio/geochemical characterization of the Earth system. Surface reflectance is usually the starting... more
Imaging spectrometers operating in the solar spectrum measure the upwelling reflected solar radiation, and are an important tool in the bio/geochemical characterization of the Earth system. Surface reflectance is usually the starting point for the retrieval of biophysical parameters from remote measurements. Reliable radiometric and spectral calibrations and accurate atmospheric correction are mandatory in the interpretation of the surface reflectance.
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In schizophrenia patients, optimal treatment with antipsychotics requires weeks to months of sustained drug therapy. However, single administration of antipsychotic drugs can reverse schizophrenia-like behavioral alterations in rodent... more
In schizophrenia patients, optimal treatment with antipsychotics requires weeks to months of sustained drug therapy. However, single administration of antipsychotic drugs can reverse schizophrenia-like behavioral alterations in rodent models of psychosis. This raises questions about the physiological relevance of such antipsychotic-like activity. This study evaluates the effects of chronic treatment with clozapine on the cellular and behavioral responses induced by the hallucinogenic serotonin 5-HT(2A) receptor agonist lysergic acid diethylamide (LSD) as a mouse model of psychosis. Mice were treated chronically (21 days) with 25 mg/kg/day clozapine. Experiments were conducted 1, 7, 14, and 21 days after the last clozapine administration. [(3)H]Ketanserin binding and 5-HT ( 2A ) mRNA expression were determined in mouse somatosensory cortex. Head-twitch behavior, expression of c-fos, which is induced by all 5-HT(2A) agonists, and expression of egr-1 and egr-2, which are LSD-like specific, were assayed. Head-twitch response was decreased and [(3)H]ketanserin binding was downregulated in 1, 7, and 14 days after chronic clozapine. 5-HT ( 2A ) mRNA was reduced 1 day after chronic clozapine. Induction of c-fos, but not egr-1 and egr-2, was rescued 7 days after chronic clozapine. These effects were not observed after short treatment (2 days) with clozapine or chronic haloperidol (1 mg/kg/day). Our findings provide a murine model of chronic atypical antipsychotic drug action and suggest downregulation of the 5-HT(2A) receptor as a potential mechanism involved in these persistent therapeutic-like effects.
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Research Interests: Psychology, Cognitive Science, Animal Behavior, Schizophrenia, Signal Transduction, and 14 moreApplied Animal Behavior, Serotonin, Glutamate, Mice, Animals, Metabotropic Glutamate Receptors, Male, Frontal Cortex, Hallucinogens, Protein Binding, Neurosciences, Binding Site, Frontal Lobe, and Signaling pathway
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Soil samples collected from locations in Kosovo where depleted uranium (DU) ammunition was expended during the 1999 Balkan conflict were analysed for uranium and plutonium isotopes content (234U, 235U, 236U, 238U, 238Pu, (239 + 240)Pu).... more
Soil samples collected from locations in Kosovo where depleted uranium (DU) ammunition was expended during the 1999 Balkan conflict were analysed for uranium and plutonium isotopes content (234U, 235U, 236U, 238U, 238Pu, (239 + 240)Pu). The analyses were conducted using gamma spectrometry (235U, 238U), alpha spectrometry (238Pu, (239 + 240)Pu), inductively coupled plasma-mass spectrometry (ICP-MS) (234U, 235U, 236U, 238U) and accelerator mass spectrometry (AMS) (236U)). The results indicated that whenever the U concentration exceeded the normal environmental values (approximately 2 to 3 mg/kg) the increase was due to DU contamination. 236U was also present in the released DU at a constant ratio of 236U (mg/kg)/238U (mg/kg) = 2.6 x 10(-5), indicating that the DU used in the ammunition was from a batch that had been irradiated and then reprocessed. The plutonium concentration in the soil (undisturbed) was about 1 Bq/kg and, on the basis of the measured 238Pu/(239 + 240)Pu, could be entirely attributed to the fallout of the nuclear weapon tests of the 1960s (no appreciable contribution from DU).
Research Interests: Yugoslavia, Environmental Monitoring, Accelerator Mass Spectrometry, Biological Sciences, Environmental Sciences, and 10 moreEnvironmental Radioactivity, Uranium, Inductively Coupled Plasma Mass Spectrometry, CHEMICAL SCIENCES, Depleted Uranium, Environmental, Environmental Value, Nuclear Warfare, PLUTONIUM, and Radioactive fallout
Research Interests: Schizophrenia, Behavior, Biological Chemistry, Biological Sciences, Humans, and 15 moreSequence alignment, Mice, Female, Animals, Male, CHEMICAL SCIENCES, Middle Aged, Adult, Amino Acid Sequence, Amino Acid Substitution Rates, Protein Binding, Dimerization, Case Control Studies, Molecular Sequence Data, and Medical and Health Sciences
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... of the fits shows that the initialization values of C v and C s are very close to those of the finalsolution. ... The simple formulation proposed by Vermote et al. ... and the availability of one single view angle make the retrieval... more
... of the fits shows that the initialization values of C v and C s are very close to those of the finalsolution. ... The simple formulation proposed by Vermote et al. ... and the availability of one single view angle make the retrieval of the aerosol model over land targets a challenging task. ...
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The Medium Resolution Imaging Spectrometer (MERIS) sensor, with its good physical design, can provide excellent data for water colour monitoring. However, owing to the shortage of shortwave-infrared (SWIR) bands, the traditional... more
The Medium Resolution Imaging Spectrometer (MERIS) sensor, with its good physical design, can provide excellent data for water colour monitoring. However, owing to the shortage of shortwave-infrared (SWIR) bands, the traditional near-infrared (NIR)–SWIR algorithm for atmospheric correction in inland turbid case II waters cannot be extended to the MERIS data directly, which limits its applications. In this study, we developed
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Abstract This paper evaluates state-of-the-art parametric and nonparametric approaches for the estimation of leaf chlorophyll content $(Chl) $, leaf area index, and fractional vegetation cover from space. The parametric approach involves... more
Abstract This paper evaluates state-of-the-art parametric and nonparametric approaches for the estimation of leaf chlorophyll content $(Chl) $, leaf area index, and fractional vegetation cover from space. The parametric approach involves comparison of established and ...
Research Interests: Geophysics, Remote Sensing, Neural Network, Nonlinear Regression, Support Vector Regression, and 13 moreGeomatic Engineering, Support vector machine, Leaf Area Index, Spectrum, Data Model, Vegetation indices, High Dimensionality, Gaussian Process, Optimal Bayesian Estimation, Indexation, Vegetation Mapping, Electrical And Electronic Engineering, and chlorophyll Content
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ABSTRACT Inversion of radiative transfer models (RTM) using a lookup-table (LUT) approach against satellite reflectance data can lead to concurrent retrievals of biophysical parameters such as leaf chlorophyll content (Chl) and leaf area... more
ABSTRACT Inversion of radiative transfer models (RTM) using a lookup-table (LUT) approach against satellite reflectance data can lead to concurrent retrievals of biophysical parameters such as leaf chlorophyll content (Chl) and leaf area index (LAI), but optimization strategies are not consolidated yet. ESA's upcoming satellites Sentinel-2 (S2) and Sentinel-3 (S3) aim to ensure continuity of old generation satellite sensors by providing superspectral images of high spatial and temporal resolution. This unprecedented data availability leads to an urgent need for developing robust, accurate, and operational retrieval methods. For three simulated Sentinel settings (S2-10 m: 4 bands, S2-20 m: 8 bands and S3-OLCI: 19 bands) various optimization strategies in LUT-based RTM inversion have been evaluated, being the role of i) added noise, ii) multiple best solutions, iii) combined parameters (Chl ×LAI), and iv) applied cost functions. By inverting the PROSAIL model and using data from the ESA-led field campaign SPARC (Barrax, Spain), it was demonstrated that introducing noise and opting for multiple best solutions in the inversion considerably improved retrievals. However, the widely used RMSE was not the best performing cost function. Three families of alternative cost functions were applied here: information measures, minimum contrast, and M-estimates. We found that so-called "Power divergence measure", "Trigonometric", and spectral measure with "Contrast function K(x) = -log(x) + x", yielded more accurate results, although this also depended on the biophysical parameter. Particularly, when simultaneous retrieval of multiple biophysical parameters is the objective then "Contrast function K(x) = -log(x) + x" provided most consistent optimized estimates of leaf Chl, LAI and canopy Chl across the different Sentinel configurations (relative RMSE: 24-29 %).
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An atmospheric correction algorithm for satel-lite/airborne data taken over land has been imple-mented. The algorithm is designed to obtain the main atmospheric parameters needed in the correc-tion from the image itself, so an optimal... more
An atmospheric correction algorithm for satel-lite/airborne data taken over land has been imple-mented. The algorithm is designed to obtain the main atmospheric parameters needed in the correc-tion from the image itself, so an optimal characteri-zation of the atmospheric ...
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... On the other hand, CHRIS measures over the visible/near-infrared (NIR) bands from 400 nm to 1050 nm, with a minimum spectral sampling interval ranging between 1.25 (@400 nm) and 11 nm (@1000 nm). ... nir red nir red NDVI ρ ρ ρ ρ − = +... more
... On the other hand, CHRIS measures over the visible/near-infrared (NIR) bands from 400 nm to 1050 nm, with a minimum spectral sampling interval ranging between 1.25 (@400 nm) and 11 nm (@1000 nm). ... nir red nir red NDVI ρ ρ ρ ρ − = + (1) ...