976 resultados para import elasticity


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The study of wave propagation at sonic frequency in soil leads to elasticity parameter determination. These parameters are compatible to those measured simultaneously by static loading. The acquisition of in situ elasticity parameter combined with laboratory description of the elastoplastic behaviour can lead to in situ elastoplastic curves. - L'étude de la propagation des ondes acoustiques permet la détermination des paramètres d'élasticité dans les sols. Ces paramètres sont cohérents avec des mesures statiques simultanées. L'acquisition des paramètres d'élasticité in situ associée à une description du comportement élasto-plastique mesuré en laboratoire permet d'obtenir des courbes d'élastoplasticité in situ.

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Loss of T-tubules (TT), sarcolemmal invaginations of cardiomyocytes (CMs), was recently identified as a general heart failure (HF) hallmark. However, whether TT per se or the overall sarcolemma is altered during HF process is still unknown. In this study, we directly examined sarcolemmal surface topography and physical properties using Atomic Force Microscopy (AFM) in living CMs from healthy and failing mice hearts. We confirmed the presence of highly organized crests and hollows along myofilaments in isolated healthy CMs. Sarcolemma topography was tightly correlated with elasticity, with crests stiffer than hollows and related to the presence of few packed subsarcolemmal mitochondria (SSM) as evidenced by electron microscopy. Three days after myocardial infarction (MI), CMs already exhibit an overall sarcolemma disorganization with general loss of crests topography thus becoming smooth and correlating with a decreased elasticity while interfibrillar mitochondria (IFM), myofilaments alignment and TT network were unaltered. End-stage post-ischemic condition (15days post-MI) exacerbates overall sarcolemma disorganization with, in addition to general loss of crest/hollow periodicity, a significant increase of cell surface stiffness. Strikingly, electron microscopy revealed the total depletion of SSM while some IFM heaps could be visualized beneath the membrane. Accordingly, mitochondrial Ca(2+) studies showed a heterogeneous pattern between SSM and IFM in healthy CMs which disappeared in HF. In vitro, formamide-induced sarcolemmal stress on healthy CMs phenocopied post-ischemic kinetics abnormalities and revealed initial SSM death and crest/hollow disorganization followed by IFM later disarray which moved toward the cell surface and structured heaps correlating with TT loss. This study demonstrates that the loss of crest/hollow organization of CM surface in HF occurs early and precedes disruption of the TT network. It also highlights a general stiffness increased of the CM surface most likely related to atypical IFM heaps while SSM died during HF process. Overall, these results indicate that initial sarcolemmal stress leading to SSM death could underlie subsequent TT disarray and HF setting.

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AbstractPPARP is a nuclear receptor responding in vivo to several free fatty acids, and implicated in cell metabolism, differentiation and survival. PPARp is ubiquitously expressed but shows high expression in the developing and adult brain. PPARp is expressed in different cell types such as neurons and astrocytes, where it might play a role in metabolism. To study this nuclear receptor the laboratory engineered a PPARP -/- mouse model. The aim of my PhD was to dissect the role of PPARP in astrocytes.Experiments in primary culture revealed that cortical astrocytes from PPARP -/- mouse have an impaired energetic metabolism. Unstimulated PPARP -/- astrocytes exhibit a 30% diminution in glucose uptake, correlating to a 30% decrease in lactate release and intracellular glucose. After acute stimulation by D- aspartate mimicking glutamate exposure, both WT and -/- astrocytes up-regulate their metabolism to respond to the increasing energy needed (ATP) for glutamate uptake. According to the Astrocyte Neuron Lactate Shuttle Hypothesis (ANLSH), the ratio between glucose uptake/ lactate release is 1. However, stimulated PPARp -/- astrocytes display a higher increase in lactate release than glucose uptake which remains lower than in WT. The extra glucose equivalents could come from the degradation of intra cellular glycogen stores, which indeed decrease in PPARP -/- cells upon stimulation. Lower glucose metabolism correlates with a decreased acute glutamate uptake in PPARP -/- astrocytes. Reciprocally, we also observed an increase of glutamate uptake and ATP production after treatment of WT astrocytes with a PPARp agonist. Glutamate transporter protein expression is not affected. However, their trafficking and localization might be altered as PPARp -/- astrocytes have higher cholesterol levels, which may also affect proper transporter structure in the membrane.Metabolism, transporter localization and cholesterol levels are respectively linked to cell mobility, cell cytoskeleton and cellular membrane composition. All three functions are important in astrocytes to in vivo acquire star shaped morphology, in a process known as stellation. PPARP -/- astrocytes showed an impaired acquired stellation in presence of neurons or chemical stimuli, as well as more actin stress fibers and cell adhesion structures. While non stellation of astrocytes is mainly an in vitro phenomenon, it reveals PPARp -/- primary astrocytes inability to respond to different exterior stimuli. These morphological phenotypes correlate with a slower migration in cell culture wound healing assays.This thesis work demonstrates that PPARp is implicated in cortical astrocyte glucose metabolism. PPARp absence leads to an unusual intracellular glycogen use. Added to the effect on acute glutamate uptake and astrocyte migration, PPARp could be an interesting target for neuroprotection therapies.RésuméPPARP est un récepteur nucléaire qui a pour ligands naturels certains acides gras libres. Il est impliqué dans le métabolisme, la différentiation et la survie des cellules. PPARP est ubiquitaire, et a une expression élevée dans le cerveau en développement ainsi qu'adulte. PPARp est exprimé dans différents types cellulaires tels que les neurones et les astrocytes, où il régule potentiellement leurs métabolismes. Pour étudier ce récepteur nucléaire, le laboratoire a créé un modèle de souris PPARp -/-. L'objectif de ma thèse est de comprendre le rôle de PPARp dans les astrocytes.Les expériences montrent un défaut du métabolisme énergétique dans les astrocytes corticaux primaires tirés de souris PPARp -/-. Sans stimulation, l'entrée du glucose dans les astrocytes PPARP -/- est diminuée de 30% ce qui correspond à une diminution de 30% du relargage du lactate. Après stimulation par du D-Aspartate qui mime une exposition au glutamate, les astrocytes WT et -/- augmentent leur métabolisme en réponse à la demande accrue en énergie (ATP) due à l'entrée du glutamate. D'après l'Astrocyte Neuron Lactate Shuttle Hypothesis (ANLSH), le ratio entre le glucose entrant et le lactate sortant est de 1. Cependant le relargage du lactate dans les astrocytes PPARP-/- est plus élevé que l'entrée du glucose. L'apport supplémentaire de glucose transformé en lactate pourrait provenir de la dégradation des stocks de glycogène intracellulaire, qui sont partiellement diminués après stimulation dans les cellules PPARP -/-. Un métabolisme plus faible du glucose corrèle avec une réduction de l'import du glutamate dans les astrocytes PPARp -/-. Réciproquement, nous observons une augmentation de l'import du glutamate et de la production d'ATP après traitement avec l'agoniste pour PPARp. Bien que l'expression des transporteurs de glutamate ne soit pas affectée, nous ne pouvons pas exclure que leur localisation et leur structure soient altérées du fait du niveau élevé de cholestérol dans les astrocytes PPARp -/-.Le métabolisme, la localisation des transporteurs et le niveau de cholestérol sont tous liés au cytosquelette, à la mobilité, et à la composition des membranes cellulaires. Toutes ces fonctions sont importantes pour les astrocytes pour acquérir leur morphologie in vivo. Les astrocytes PPARP -/- présentent un défaut de stellation, aussi bien en présence de neurones que de stimuli chimiques, ainsi qu'un plus grand nombre de fibres de stress (actine) et de structures d'adhésion cellulaire. Bien que les astrocytes non stellaires soient principalement observés in vitro, le défaut de stellation des astrocytes primaires PPARp -/- indique une incapacité à répondre aux différents stimuli extérieurs. Ces phénotypes morphologiques corrèlent avec une migration plus lente en cas de lésion de la culture.Ce travail de thèse a permis de démontrer l'implication de PPARP dans le métabolisme du glucose des astrocytes corticaux. L'absence de ce récepteur nucléaire amène à l'utilisation du glucose intracellulaire, auquel s'ajoutent les effets sur l'import du glutamate et la migration des astrocytes. PPARp aurait des effets neuroprotecteurs, et de ce fait pourrait être utilisé à des fins thérapeutiques.

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Las aplicaciones que se distribuyen a través de Internet como un servicio (Software as a service, SaaS) y el hardware y software de base de los centros de datos (Nube, Cloud) son los dos elementos de la ecuación llamada cloud computing. En este paradigma, se juegan tres roles principales: proveedor del cloud, usuario del cloud que a su vez es proveedor de servicio (como los repositorios) y los usuarios finales del servicio. Los primeros se benefician de la especialización y las economías de escala; mientras que los segundos de una mayor elasticidad en el aprovisionamiento. En este sentido, DuraSpace ha creado un piloto llamado DuraCloud para probar el uso de tecnologías de almacenamiento en la nube para la preservación de contenido digital. El taller pretende describir los conceptos básicos del cloud, con ejemplos de donde se está usando este tipo de tecnología; y el impacto que puede tener en los repositorios digitales.

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BACKGROUND: Alterations in glucose metabolism and epithelial-mesenchymal transition (EMT) constitute two important characteristics of carcinoma progression toward invasive cancer. Despite an extensive characterization of each of them separately, the links between EMT and glucose metabolism of tumor cells remain elusive. Here we show that the neuronal glucose transporter GLUT3 contributes to glucose uptake and proliferation of lung tumor cells that have undergone an EMT. RESULTS: Using a panel of human non-small cell lung cancer (NSCLC) cell lines, we demonstrate that GLUT3 is strongly expressed in mesenchymal, but not epithelial cells, a finding corroborated in hepatoma cells. Furthermore, we identify that ZEB1 binds to the GLUT3 gene to activate transcription. Importantly, inhibiting GLUT3 expression reduces glucose import and the proliferation of mesenchymal lung tumor cells, whereas ectopic expression in epithelial cells sustains proliferation in low glucose. Using a large microarray data collection of human NSCLCs, we determine that GLUT3 expression correlates with EMT markers and is prognostic of poor overall survival. CONCLUSIONS: Altogether, our results reveal that GLUT3 is a transcriptional target of ZEB1 and that this glucose transporter plays an important role in lung cancer, when tumor cells loose their epithelial characteristics to become more invasive. Moreover, these findings emphasize the development of GLUT3 inhibitory drugs as a targeted therapy for the treatment of patients with poorly differentiated tumors.

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Geographical Information Systems (GIS) facilitate access to epidemiological data through visualization and may be consulted for the development of mathematical models and analysis by spatial statistics. Variables such as land-cover, land-use, elevations, surface temperatures, rainfall etc. emanating from earth-observing satellites, complement GIS as this information allows the analysis of disease distribution based on environmental characteristics. The strength of this approach issues from the specific environmental requirements of those causative infectious agents, which depend on intermediate hosts for their transmission. The distribution of these diseases is restricted, both by the environmental requirements of their intermediate hosts/vectors and by the ambient temperature inside these hosts, which effectively govern the speed of maturation of the parasite. This paper discusses the current capabilities with regard to satellite data collection in terms of resolution (spatial, temporal and spectral) of the sensor instruments on board drawing attention to the utility of computer-based models of the Earth for epidemiological research. Virtual globes, available from Google and other commercial firms, are superior to conventional maps as they do not only show geographical and man-made features, but also allow instant import of data-sets of specific interest, e.g. environmental parameters, demographic information etc., from the Internet.

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The photoreceptor phytochrome B (phyB) interconverts between the biologically active Pfr (λmax = 730 nm) and inactive Pr (λmax = 660 nm) forms in a red/far-red-dependent fashion and regulates, as molecular switch, many aspects of light-dependent development in Arabidopsis thaliana. phyB signaling is launched by the biologically active Pfr conformer and mediated by specific protein-protein interactions between phyB Pfr and its downstream regulatory partners, whereas conversion of Pfr to Pr terminates signaling. Here, we provide evidence that phyB is phosphorylated in planta at Ser-86 located in the N-terminal domain of the photoreceptor. Analysis of phyB-9 transgenic plants expressing phospho-mimic and nonphosphorylatable phyB-yellow fluorescent protein (YFP) fusions demonstrated that phosphorylation of Ser-86 negatively regulates all physiological responses tested. The Ser86Asp and Ser86Ala substitutions do not affect stability, photoconversion, and spectral properties of the photoreceptor, but light-independent relaxation of the phyB(Ser86Asp) Pfr into Pr, also termed dark reversion, is strongly enhanced both in vivo and in vitro. Faster dark reversion attenuates red light-induced nuclear import and interaction of phyB(Ser86Asp)-YFP Pfr with the negative regulator PHYTOCHROME INTERACTING FACTOR3 compared with phyB-green fluorescent protein. These data suggest that accelerated inactivation of the photoreceptor phyB via phosphorylation of Ser-86 represents a new paradigm for modulating phytochrome-controlled signaling.

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Roughly fifteen years ago, the Church of Jesus Christ of Latter-day Saints published a new proposed standard file format. They call it GEDCOM. It was designed to allow different genealogy programs to exchange data.Five years later, in may 2000, appeared the GENTECH Data Modeling Project, with the support of the Federation of Genealogical Societies (FGS) and other American genealogical societies. They attempted to define a genealogical logic data model to facilitate data exchange between different genealogical programs. Although genealogists deal with an enormous variety of data sources, one of the central concepts of this data model was that all genealogical data could be broken down into a series of short, formal genealogical statements. It was something more versatile than only export/import data records on a predefined fields. This project was finally absorbed in 2004 by the National Genealogical Society (NGS).Despite being a genealogical reference in many applications, these models have serious drawbacks to adapt to different cultural and social environments. At the present time we have no formal proposal for a recognized standard to represent the family domain.Here we propose an alternative conceptual model, largely inherited from aforementioned models. The design is intended to overcome their limitations. However, its major innovation lies in applying the ontological paradigm when modeling statements and entities.

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Summary The Wnt signaling pathway plays an important role during development and also for maintaining tissue homeostasis due to its function in proliferation, differentiation and cell fate decisions. Wnt ligands bind to Frizzled receptors and activate a signaling cascade that results in the stabilization of β-Catenin, a key component of the pathway. β-Catenin translocates to the nucleus, where, together with a transcription factor of the Tcf/Lef family, it activates the expression of target genes. Legless and Pygopus are two recently discovered essential components of the Wnt pathway in Drosophila, which may mediate the nuclear import and retention of beta-Catenin and/or contribute directly to the activation of Wnt target genes. To address the function of Legless in the mouse, we have generated compound constitutive and conditional knockout alleles of the two homologues legless 'I (bc1-9) and 2. We have induced the deletion of legless in self-renewing tissues such as the gastrointestinal tract, the mammary gland and the skin during adulthood and constitutively in the embryo. The present thesis focused on the consequences of the inactivation of legless in epithelial homeostasis as well as in a regeneration model and its comparison to pygopus. Deletion of neither legless nor pygopus in the adult small intestine resulted in any apparent anomaly, contrasting expectations from the phenotype caused by over-expression of Dickkopf, a Wnt inhibitor (Pinto et al., 2003). These observations indicate that canonical Wnt signaling might not be indispensable for normal gastrointestinal epithelium homeostasis, or that, in this context, Legless and Pygopus are not essential components of the Wnt pathway. However, the regeneration of the colonic epithelium after DSS induced damage was markedly impaired in legless, but not in pygopus deficient mice. Thus, unlike in Drosophila, deletion of mammalian legless and pygopus resulted in different phenotypes, suggesting that Legless might interact with as yet unidentified partners in addition to Pygopus. Resumé La voie de signalisation Wnt joue un rôle important au cours du développement ainsi que pour le maintien de l' homéostase tissulaire due à sa fonction durant la prolifération, la différentiation et les décisions sur l'avenir des cellules. Les ligands de Wnt se lient aux récepteurs Frizzled et activent une cascade de signalisation résultant en la stabilisation de β-Catenin, un composant central de cette voie. β-Catenin est transloquée dans le noyau ou, avec l'aide des facteurs de transcription de la famille Tcf/lef, elle active la transcription des gènes cibles. Legless et Pygopus sont deux composants récemment découverts et essentiels de la voie de signalisation Wnt chez la Drosophile qui pourraient être des médiateurs de l'import et de la rétention nucléaire de bêta-catenin et/ou contribuer directement a l'activation des gènes cibles. Afin de comprendre la fonction de Legless chez la souris, nous avons généré simultanément les allèles « knock-out » constitutifs et conditionnels des deux homologues legless 1 (bc1-9) et 2. Nous avons induit la délétion de legless dans des tissus capables de s'auto renouveler comme le tract gastro-intestinal, la glande mammaire et la peau chez l'adulte et nous avons supprimé constitutivement legless chez l'embryon. La présente thèse est concentrée sur les conséquences de l'inactivation de legless au cours de l' homéostase épithéliale ainsi que dans un modèle de régénération et sur sa comparaison avec pygopus. Ni la délétion de legless ni celle de pygopus dans l'intestin adulte n'ont résulté en quelque anomalie, contrastant nos attentes provenant des phénotypes causes par la surexpression de Dickkpof, un inhibiteur de Wnt (Pinto et al., 2003). Ces observations indiquent que la voie de signalisation Wnt/β-Catenin pourrait ne pas être indispensable à l' homéostase normale du tract gastro-intestinal, ou que, dans ce contexte, Legless et Pygopus ne sont pas des composants essentiels de la vole Wnt. Cependant, la régénération de l'épithélium du colon après induction de son endommagement au DSS fut dramatiquement diminuée chez legless mais pas chez les souris mutantes pour pygopus. Ainsi, a la différence de chez la Drosophile, la délétion de legless et pygopus chez les mammifères a résulté en des phénotypes différents, suggérant que Legless pourrait interagir avec d'autres partenaires, encore non identifies, que Pygopus.

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La fibrosi pulmonar idiopàtica (FPI) és una malaltia intersticial letal, d'etiologia desconeguda i per la que no es disposa de cap tractament efectiu. Creiem que l’elasticitat normal del pulmó té propietats anti-fibròtiques, de manera que la FPI només progressarà si es produeix un enduriment sostingut del teixit. Per això hem dissenyat dos assaigs que ens permetran examinar els efectes pro-fibròtics de l'enduriment extracel•lular sobre fibroblasts primaris de pulmó. Els dos assaigs d'enduriment es basen en gels de poliacrilamida 2D i en gels de col•lagen 3D. Els fibroblasts s'han cultivat en el model d'enduriment 3D en presència o absència de la citoquina pro-fibròtica TGF-β1 i s'ha analitzat com la combinació de l’enduriment extracelular i la TGF-b1 modifiquen el fenotip de les cèl.lules. Els resultats preliminars mostren canvis en l'expressió d'alguns gens en resposta a l'enduriment i al TGF-b1, així com diferències entre cel•lules normals i fibròtiques. A més, suggereixen que l'expressió de COL1A1 i MMP-1 és mecanosensible, i que la seva desregulació podria estar associada a l’enduriment anòmal característic dels pulmons amb FPI.

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BACKGROUND: The alcohol purchase task (APT), which presents a scenario and asks participants how many drinks they would purchase and consume at different prices, has been used among students and small clinical samples to obtain measures of alcohol demand but not in large, general population samples. METHODS: We administered the APT to a large sample of young men from the general population (Cohort Study on Substance Use Risk Factors). Participants who reported drinking in the past year (n=4790), reported on past 12 months alcohol use, on DSM-5 alcohol use disorder (AUD) criteria and on alcohol related consequences were included. RESULTS: Among the APT's demand parameters, intensity was 8.7 (SD=6.5) indicating that, when drinks are free, participants report a planned consumption of almost 9 drinks. The maximum alcohol expenditure (Omax) was over 35CHF (1CHF=1.1USD) and the demand became elastic (Pmax) at 8.4CHF (SD=5.6). The mean price at which the consumption was suppressed was 15.6CHF (SD=5.4). Exponential equation provided a satisfactory fit to individual responses (mean R(2): 0.8, median: 0.8). Demand intensity was correlated with alcohol use, number of AUD criteria and number of consequences (all r≥0.3, p<0.0001). Omax was correlated with alcohol use (p<0.0001). The elasticity parameter was weakly correlated with alcohol use in the expected direction. CONCLUSION: The APT measures are useful in characterizing demand for alcohol in young men in the general population. Demand may provide a clinically useful index of strength of motivation for alcohol use in general population samples.

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En aquest projecte s’ha treballat amb una entitat no governamental, que es troba en la regió de Bahia (Brasil). L’associació “Mecenas da Vida” és una ONG que treballa en l’àmbit de la conservació del medi natural, fent partícips la pròpia població local. Petits agricultors dels municipis d’Itacaré i Uruçuca a l’Estat de Bahia que formen part del projecte, realitzen pràctiques conservacionistes i en compensació reben un pagament, per aquests serveis. Aquests diners provenen d’una taxa voluntària que paguen alguns empresaris turístics dels mateixos municipis. Pagant aquest import, els empresaris obtenen un segell distintiu que acredita la compensació de les seves emissions de CO2. El projecte tracta d’aportar un model de càlcul més específic al seuprograma de neutralització de carboni, amb sistemes agroforestals (SAF).No s’han trobat fonts d’informació sobre monitoratge de carboni en SAF en aquesta regió

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Introduction: Nasal continuous positive airways pressure (n-CPAP) is an effective treatment in premature infants with respiratory distress. The cardio-pulmonary interactions secondary to n-CPAP are well studied in adults, but less well described in premature infants. We postulated that there could be important interactions with regard to the patent ductus arteriosus (PDA). Methods: Prospective study, approved by the local ethic committee. Premature infants less than 32 weeks gestation, _7 days-old, needing n-CPAP for respiratory distress, but without the need of additional oxygen were included in the study. Every patient had a first echocardiography with n-CPAP and then n-CPAP was retrieved. 3 hours later the echocardiography was repeated by the same investigator and then the patient replaced on n-CPAP. Results: 14 premature newborn were included, mean gestational age of 28 _ 2 weeks, mean weight 1.1 _ 0.3 Kg and height 39 _ 3 cm. Echocardiographic measurements are depicted in Table 1. Significant finding were observed between measurement on n- CPAP or without n-CPAP: on end diastolic left ventricular diameter (12.8 _ 1.6 mm vs. 13.5 _ 2 mm), on end systolic left ventricular diameter (8.4 _ 1.3 mm vs. 9.1 _ 1.5 mm), left atrium diameter (8.9 _ 2.2 mm vs. 10.4 _ 2.5 mm), maximal velocity on tricuspid valve (46 _ 10 cm/s vs. 51 _ 9 cm/s), calculated Qp (3.7 _ 0.8 L/min/m2 vs. 4.3 _ 0.8 L/min/m2). Only three patients have demonstrated a PDA during the study. Conclusion: Positive end expiratory pressure (Peep) has hemodynamic effects which are: reduction of systemic and pulmonary venous return as shown by the changes on tricuspid valve inflow,on the calculated Qp and finally on the diameter of the left atrium and left ventricle.We found in premature infants the same hemodynamic effects than those described in adults but with lower Peep values. This could be due to the particular elasticity and weakness of the thoracic wall of premature infants. Interestingly the flow through a PDA seems also to be diminished with Peep, but the number of patients is insufficient to conclude. Further investigation will be needed to better understand these interactions. Table 1. Echocardiographic measurement (mean (SD)). With n-CPAP Without n-CPAP p value RV ED diameter (mm) 6.3 (1.7) 6.04 (1.1) NS LV ED diameter (mm) 12.8 (1.6) 13.5 (2.0) _0.05 LV ES diameter (mm) 8.4 (1.3) 9.1 (1.5) _0.05 SF (%) 34 (5) 33 (6) NS Ao valve diameter (mm) 7.4 (1.3) 7.4 (1.2) NS LA diameter (mm) 8.9 (2.2) 10.4 (2.5) _0.05 Vmax Ao (cm/s) 70 (16) 71 (18) NS Vmax PV (cm/s) 69 (15) 72 (16) NS Vmax TV (cm/s) 46 (10) 51 (9) _0.05 Vmax MV (cm/s) 53 (17) 54 (18) NS Qp (L/min/m2) 3.7 (0.8) 4.3 (0.8) _0.05 Qs (L/min/m2) 4.0 (0.8) 4.0 (0.7) NS Qp/Qs 0.92 (0.14) 1.09 (0.23) _0.05 RV: right ventricle, LV: left ventricle, ED: end diastolic, ES: end systolic, SF: shortening fraction,Ao: aortic valve, LA: left atrium,Vmax: maximum Doppler Velocity, Qp: pulmonary output, Qs: systemic output, NS: non significant.

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Using a panel of 48 provinces for four years we empirically analyze a series of temporary policies aimed at curbing fuel consumption implemented in Spain between March and June 2011. The first policy was a reduction in the speed limit in highways. The second policy was an increase in the biofuel content of fuels used in the transport sector. The third measure was a reduction of 5% in commuting and regional train fares that resulted in two major metropolitan areas reducing their overall fare for public transit. The results indicate that the speed limit reduction in highways reduced gasoline consumption by between 2% and 3%, while an increase in the biofuel content of gasoline increased this consumption. This last result is consistent with experimental evidence that indicates that mileage per liter falls with an increase in the biofuel content in gasolines. As for the reduction in transit fares, we do not find a significant effect for this policy. However, in specifications including the urban transit fare for the major cities in each province the estimated cross-price elasticity of the demand for gasoline -used as a proxy for car use- with respect to the price of transit is within the range reported in the literature. This is important since one of the main eficiency justification for subsidizing public transit rests on the positive value of this parameter and most of the estimates reported in the literature are quite dated.

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El projecte ha assolit la majoria d’objectius, ajustats a la reducció d'una quarta part de l'import concedit: 1) caracteritzar la transformació del paisatge agro-forestal i urbà a dos municipis de la vall del Congost, La Garriga i Figaró-Montmany, reconstruint amb SIG els mapes d'ús del sòl de 1854, 1949, 1956 i 2005, obtenint per intersecció de cobertes les matrius dels canvis d'ús; i 2) avaluar amb l’índex de connectivitat ecològica l'impacte ambiental d'aquells canvis des del punt de vista de la biodiversitat i la resiliència del paisatges, amb un especial èmfasi en la reforestació induïda per l'abandonament rural i la pèrdua de paisatges en mosaic, en un àmbit més gran pel període 1956-1993-2005. Aquests resultats han permès preparar varis articles per publicar en co-autoría a revistes com Landscape History, Environment and History o Landscape and Urban Planning. Ja és a punt de poder-se lliurar el primer amb el títol de "Looking backwards into a Mediterranean edge environment: Landscape changes and ecological connectivity in El Congost Valley (province of Barcelona, Catalonia) 1850-2005", incloent dos objectius esmentats a la memòria: identificar les principals forces motores d'aquells canvis en el paisatge relacionant els usos del sòl amb les formes d'ordenació del territori, caracteritzar-ne les forces rectores econòmico-socials i el paper jugat per la protecció del Parc Natural del Montseny i els Cingles de Bertí. Els resultats també permetran abordar en el futur altres aspectes, com per exemple estimar el potencial energètic de la biomassa local tot cercant que el seu aprofitament generi sinèrgies territorials positives per a l'ecologia del paisatge amb la recuperació d’una ramaderia extensiva i una agricultura ecològica que facin possible la restauració dels paisatges en mosaic. L'estudi ha pogut incorporar un aspecte inicialment no previst, el cens d'orquídies mediterrànies a Figaró-Montmany elaborat pel naturalista Paul Wilcox.