Extrapolating Satellite Winds to Turbine Operating Heights

Ocean wind retrievals from satellite sensors are typically performed for the standard level of 10 m. This restricts their full exploitation for wind energy planning, which requires wind information at much higher levels where wind turbines operate. A new method is presented for the vertical extrapolation of satellite-based wind maps. Winds near the sea surface are obtained from satellite data and used together with an adaptation of the Monin–Obukhov similarity theory to estimate the wind speed at higher levels. The thermal stratification of the atmosphere is taken into account through a long-term stability correction that is based on numerical weather prediction (NWP) model outputs. The effect of the long-term stability correction on the wind profile is significant. The method is applied to Envisat Advanced Synthetic Aperture Radar scenes acquired over the south Baltic Sea. This leads to maps of the long-term stability correction and wind speed at a height of 100 m with a spatial resolution of 0.02°. Calculations of the corresponding wind power density and Weibull parameters are shown. Comparisons with mast observations reveal that NWP model outputs can correct successfully for long-term stability effects and also, to some extent, for the limited number of satellite samples. The satellite-based and NWP-simulated wind profiles are almost equally accurate with respect to those from the mast. However, the satellite-based maps have a higher spatial resolution, which is particularly important in nearshore areas where most offshore wind farms are built.

Dinâmica do fósforo em cultivo heterotrófico e produção de compostos celulares por cianobactéria integrado a biorrefinarias agroindustriais

O objetivo desta tese foi avaliar a dinâmica do fósforo em cultivo heterotrófico e produção de compostos celulares por Aphanothece microscopica Nägeli visando avaliar a perspectiva de implementação de uma biorrefinaria microalgal. Desta forma, foi avaliado o comportamento do micro-organismo em estudo no cultivo heterotrófico, utilizando como meio de cultivo o efluente de laticínios. O trabalho foi desenvolvido em 3 etapas. Em um primeiro momento foi avaliada a influência da temperatura (20 e 30°C) e os valores máximos e mínimos de nutrientes, em especial do fósforo dissolvido reativo (PDR), disponíveis no efluente de laticínio, na remoção de nutrientes. Os resultados demonstraram que a concentração inicial de fósforo dissolvido e a temperatura exerceram influência no crescimento celular e na eficiência de remoção de nutrientes. Em termos de otimização de processo os cultivos conduzidos a 20°C e maiores concentrações de PDR (5,5 mg.L-1 ) no efluente de laticínio, foram os mais eficientes na conversão de poluentes em biomassa e remoção de nutrientes. A segunda etapa foi desenvolvida com o objetivo de avaliar a dinâmica de distribuição de fósforo na fase líquida e sólida do reator heterotrófico, quando o efluente de laticínio foi tratado pela Aphanothece microscopica Nägeli, a 20°C e nas máximas concentrações de fósforo dissolvido encontradas no efluente. Foi demonstrado que as formas fosforadas na fase líquida do reator se caracterizam pela predominância da fração dissolvida em comparação à particulada e por apresentar como fração predominante a de fósforo orgânico. No que se refere à fase sólida, ficou demonstrado que a Aphanothece microscopica Nägeli, quando cultivada heterotroficamente apresenta 3,8 vezes mais fósforo que o requerido para o crescimento celular. Ficando demonstrado ainda que a remoção biológica de fósforo por Aphanothece microscopica Nägeli pode resultar em substanciais aportes financeiros para as estações de tratamento de efluentes. Uma terceira etapa foi desenvolvida, a qual teve como objetivo avaliar a estimativa de produção de compostos celulares por Aphanothece microscopica Nägeli, a partir do efluente de laticínio, bem como o efeito da redução de temperatura de cultivo no teor de lipídios , no momento em que é obtida a máxima concentração deste componente celular, nas condições otimizadas.Foi obtido na fase logarítmica de crescimento, concentrações de 41,8 % de proteinas, carboidratos 28,5 %, lipídios 10,4 % e minerais 10,8 %. O maior teor de lipídio registrado a 20°C correspondeu a biomassa analisada na fase logarítmica.Com a redução da temperatura para 5°C por um período de 30 h é possível obter concentrações de lipídios 2,4 vezes superior ao registrado na fase logarítmica a 20 °C. No entanto, não foram indicadas diferenças significativas (p≤0,05) em função da temperatura entre as concentrações de lipídios obtidas para a biomassa a 10°C em 40 h. O perfil de ácidos graxos da biomassa gerada a 20°C, apresentou como ácidos graxos majoritários, os ácidos graxos: palmítico, oléico, γ-linolênico, palmitoleico e esteárico, resultando um aumento na concentração de ácidos graxos saturados as espensa dos insaturados, quando a temperatura é reduzida. Em paralelo,um reator heterotrófico descontinuo foi definido, ficando demonstrado que a extrapolação da operação em batelada para contínua requer um biorreator heterotrófico com volume útil de trabalho de 240,51 m 3 , permitindo tratar 950 m3 diários de efluente, gerando 11,8 kg.d-1 de biomassa útil para produção de compostos celulares por Aphanothece microscopica Nägeli, visando à simultânea remoção de matéria orgânica, nitrogênio total e fósforo total, gerando insumos que podem suportar a implementação de uma biorrefinaria microalgal.

Efeito anti-inflamatório do heparinóide isolado do camarão Litopenaeus vannamei sobre a peritonite aguda

In recent years the heparin has been the subject of several studies that aim to expand its use as a therapeutic agent, due to its ability to modulate the activity of various proteins that play important roles in the regulation of pathophysiological processes. In several experiments and preclinical trials, heparin has demonstrated an anti-inflammatory role. However, its clinical use is limited, due to its strong anticoagulant activity and hemorrhagic complications. For this reason, considerable efforts have been employed in discovery of heparin analogous (heparinoid) with reduced side effects, that retain the anti-inflammatory properties of heparin. In this context, a heparinoid obtained from the head of Litopenaeus vannamei shrimp, which presents a structural similarity to heparin, showed, in previous studies, anti-inflammatory activity in a model of acute peritonitis with reduced anticoagulant effect in vitro and low hemorrhagic activity. Thus, the present work had as objective to evaluate the effect the heparinoid of the cephalothorax of gray shrimp on the acute inflammatory response in different times (3 or 6 hours after the induction of inflammatory stimulus), using the model of acute peritonitis induced in mice. It was also analyzed the HL effect over the activity of elastase, an enzyme involved in leukocyte recruitment. Furthermore to check if the different doses of heparin and heparinoid change the hemostatic balance in vivo, was assessed the effect of these compounds on the plasma clotting time in animals submitted to inflammation. The results show that in 3 hours, all doses of heparinoid were able to prevent efficiently in the acute inflammatory process without any anticoagulant effects, unlike the extrapolation dose of heparin, which has induced a large hemorrhage due its high anticoagulant activity. However, 6 hours after induction of inflammation, only the dosages of 0.1 and 1.0 μg/Kg of heparin and 1.0 μg/Kg of heparinoid kept anti-migratory effect, without changing of the hemostatic balance. These results indicate that the anti-migratory effect of theses compounds depends on the dosage and time of inflammatory stimulus. The HL and heparin were also able to inhibit the activity of the enzyme elastase. The discovery of this bioactive compound in the cephalothorax of shrimps can arouse great interest in biotechnology, since this compound could be useful as a structural model interesting for the development of new therapeutic agents for peritonitis

Effective Approaches to Enhancing the Social Dimension of Higher Education

Despite all intentions in the course of the Bologna Process and decades of investment into improving the social dimension, results in many national and international studies show that inequity remains stubbornly persistent, and that inequity based on socio-economic status, parental education, gender, country-of-origin, rural background and more continues to prevail in our Higher Education systems and at the labour market. While improvement has been shown, extrapolation of the gains of the last 40 years in the field show that it could take over 100 years for disadvantaged groups to catch up with their more advantaged peers, should the current rate of improvement be maintained. Many of the traditional approaches to improving equity have also necessitated large-scale public investments, in the form of direct support to underrepresented groups. In an age of austerity, many countries in Europe are finding it necessary to revisit and scale down these policies, so as to accommodate other priorities, such as balanced budgets or dealing with an aging population. An analysis of the current situation indicates that the time is ripe for disruptive innovations to mobilise the cause forward by leaps and bounds, instead of through incrementalist approaches. Despite the list of programmes in this analysis there is very little evidence as to the causal link between programmes, methodologies for their use and increases/improvements in equity in institutions. This creates a significant information gap for institutions and public authorities seeking for indicators to allocate limited resources to equity improving initiatives, without adequate evidence of effectiveness. The IDEAS project and this publication aims at addressing and improving this information gap. (DIPF/Orig.)

Theory of mind after mild TBI in preschool children : a longitudinal perspective

Les enfants d’âge préscolaire (≤ 5 ans) sont plus à risque de subir un traumatisme crânio-cérébral (TCC) que les enfants plus agés, et 90% de ces TCC sont de sévérité légère (TCCL). De nombreuses études publiées dans les deux dernières décennies démontrent que le TCCL pédiatrique peut engendrer des difficultés cognitives, comportementales et psychiatriques en phase aigüe qui, chez certains enfants, peuvent perdurer à long terme. Il existe une littérature florissante concernant l'impact du TCCL sur le fonctionnement social et sur la cognition sociale (les processus cognitifs qui sous-tendent la socialisation) chez les enfants d'âge scolaire et les adolescents. Or, seulement deux études ont examiné l'impact d'un TCCL à l'âge préscolaire sur le développement social et aucune étude ne s'est penchée sur les répercussions socio-cognitives d'un TCCL précoce (à l’âge préscolaire). L'objectif de la présente thèse était donc d'étudier les conséquences du TCCL en bas âge sur la cognition sociale. Pour ce faire, nous avons examiné un aspect de la cognition sociale qui est en plein essor à cet âge, soit la théorie de l'esprit (TE), qui réfère à la capacité de se mettre à la place d'autrui et de comprendre sa perspective. Le premier article avait pour but d'étudier deux sous-composantes de la TE, soit la compréhension des fausses croyances et le raisonnement des désirs et des émotions d'autrui, six mois post-TCCL. Les résultats indiquent que les enfants d'âge préscolaire (18 à 60 mois) qui subissent un TCCL ont une TE significativement moins bonne 6 mois post-TCCL comparativement à un groupe contrôle d'enfants n'ayant subi aucune blessure. Le deuxième article visait à éclaircir l'origine de la diminution de la TE suite à un TCCL précoce. Cet objectif découle du débat qui existe actuellement dans la littérature. En effet, plusieurs scientifiques sont d'avis que l'on peut conclure à un effet découlant de la blessure au cerveau seulement lorsque les enfants ayant subi un TCCL sont comparés à des enfants ayant subi une blessure n'impliquant pas la tête (p.ex., une blessure orthopédique). Cet argument est fondé sur des études qui démontrent qu'en général, les enfants qui sont plus susceptibles de subir une blessure, peu importe la nature de celle-ci, ont des caractéristiques cognitives pré-existantes (p.ex. impulsivité, difficultés attentionnelles). Il s'avère donc possible que les difficultés que nous croyons attribuables à la blessure cérébrale étaient présentes avant même que l'enfant ne subisse un TCCL. Dans cette deuxième étude, nous avons donc comparé les performances aux tâches de TE d'enfants ayant subi un TCCL à ceux d'enfants appartenant à deux groupes contrôles, soit des enfants n'ayant subi aucune blessure et à des pairs ayant subi une blessure orthopédique. De façon générale, les enfants ayant subi un TCCL ont obtenu des performances significativement plus faibles à la tâche évaluant le raisonnement des désirs et des émotions d'autrui, 6 mois post-blessure, comparativement aux deux groupes contrôles. Cette étude visait également à examiner l'évolution de la TE suite à un TCCL, soit de 6 mois à 18 mois post-blessure. Les résultats démontrent que les moindres performances sont maintenues 18 mois post-TCCL. Enfin, le troisième but de cette étude était d’investiguer s’il existe un lien en la performance aux tâches de TE et les habiletés sociales, telles qu’évaluées à l’aide d’un questionnaire rempli par le parent. De façon intéressante, la TE est associée aux habiletés sociales seulement chez les enfants ayant subi un TCCL. Dans l'ensemble, ces deux études mettent en évidence des répercussions spécifiques du TCCL précoce sur la TE qui persistent à long terme, et une TE amoindrie seraient associée à de moins bonnes habiletés sociales. Cette thèse démontre qu'un TCCL en bas âge peut faire obstacle au développement sociocognitif, par le biais de répercussions sur la TE. Ces résultats appuient la théorie selon laquelle le jeune cerveau immature présente une vulnérabilité accrue aux blessures cérébrales. Enfin, ces études mettent en lumière la nécessité d'étudier ce groupe d'âge, plutôt que d'extrapoler à partir de résultats obtenus avec des enfants plus âgés, puisque les enjeux développementaux s'avèrent différents, et que ceux-ci ont potentiellement une influence majeure sur les répercussions d'une blessure cérébrale sur le fonctionnement sociocognitif.

Hypothesis test for changes in variance using a statistic based in P-values in a time series of normal independent observations.

The present work proposes a Hypothesis Test to detect a shift in the variance of a series of independent normal observations using a statistic based on the p-values of the F distribution. Since the probability distribution function of this statistic is intractable, critical values were we estimated numerically through extensive simulation. A regression approach was used to simplify the quantile evaluation and extrapolation. The power of the test was simulated using Monte Carlo simulation, and the results were compared with the Chen test (1997) to prove its efficiency. Time series analysts might find the test useful to address homoscedasticity studies were at most one change might be involved.

Triangular mesh parameterization with trimmed surfaces

Given a 2manifold triangular mesh \(M \subset {\mathbb {R}}^3\), with border, a parameterization of \(M\) is a FACE or trimmed surface \(F=\{S,L_0,\ldots, L_m\}\) -- \(F\) is a connected subset or region of a parametric surface \(S\), bounded by a set of LOOPs \(L_0,\ldots ,L_m\) such that each \(L_i \subset S\) is a closed 1manifold having no intersection with the other \(L_j\) LOOPs -- The parametric surface \(S\) is a statistical fit of the mesh \(M\) -- \(L_0\) is the outermost LOOP bounding \(F\) and \(L_i\) is the LOOP of the ith hole in \(F\) (if any) -- The problem of parameterizing triangular meshes is relevant for reverse engineering, tool path planning, feature detection, redesign, etc -- Stateofart mesh procedures parameterize a rectangular mesh \(M\) -- To improve such procedures, we report here the implementation of an algorithm which parameterizes meshes \(M\) presenting holes and concavities -- We synthesize a parametric surface \(S \subset {\mathbb {R}}^3\) which approximates a superset of the mesh \(M\) -- Then, we compute a set of LOOPs trimming \(S\), and therefore completing the FACE \(F=\ {S,L_0,\ldots ,L_m\}\) -- Our algorithm gives satisfactory results for \(M\) having low Gaussian curvature (i.e., \(M\) being quasi-developable or developable) -- This assumption is a reasonable one, since \(M\) is the product of manifold segmentation preprocessing -- Our algorithm computes: (1) a manifold learning mapping \(\phi : M \rightarrow U \subset {\mathbb {R}}^2\), (2) an inverse mapping \(S: W \subset {\mathbb {R}}^2 \rightarrow {\mathbb {R}}^3\), with \ (W\) being a rectangular grid containing and surpassing \(U\) -- To compute \(\phi\) we test IsoMap, Laplacian Eigenmaps and Hessian local linear embedding (best results with HLLE) -- For the back mapping (NURBS) \(S\) the crucial step is to find a control polyhedron \(P\), which is an extrapolation of \(M\) -- We calculate \(P\) by extrapolating radial basis functions that interpolate points inside \(\phi (M)\) -- We successfully test our implementation with several datasets presenting concavities, holes, and are extremely nondevelopable -- Ongoing work is being devoted to manifold segmentation which facilitates mesh parameterization

Utilização de matérias primas vegetais para aplicabilidade como inibidores de corrosão

In the search for products that act as corrosion inhibitors and do not cause environmental, impact the use of plant extracts as corrosion inhibitors is becoming a promising alternative. In this work the efficiency of polar extracts (ethanol extracts) obtained from the plants Anacardium occidentale Linn (AO) and Phyllantus amarus Schum. & Thonn (PA) as corrosion inhibitors were evaluated in different concentrations. For that AO and PA extracts were solubilized in the microemulsion systems (SME) containing saponified coconut oil as surfactant (SME -OCS and SME-OCS-1) in saline (NaCl 3,5 %) solution, which was also used as electrolyte. Both SME-OCS and SME-OCS-1 were characterized by surface tension and viscosity methods showing a Newtonian fluid behavior. The SME-OCS and SME-OCS-1 systems satisfactorily solubilized the polar extracts AO and PA with measurements carried out by ultraviolet spectroscopy. The measurements of corrosion inhibition efficiencies were performed by the electrochemical linear polarization resistance (LPR) technique as well as weight loss, on the surface of AISI 1020 carbon steel. The maximum corrosion inhibition efficiencies were determined by extrapolation of Tafel plots, showing the following values: 95,6 % for the system SME-OCS-AO, 98,9 % for the system SME-OCS-AO-1 and 93,4 % for the system SME-OCS-PA

Caractérisation pharmacocinétique et pharmacodynamique de la lidocaïne avec ou sans adrénaline lors d’un bloc paravertébral du plexus brachial chez le chien

Au cours des vingt dernières années, l’anesthésie régionale est devenue, autant en médecine vétérinaire qu’humaine, un outil essentiel à l’élaboration de protocoles analgésiques péri-opératoires. Parmi l’éventail de techniques mises au point en anesthésie canine, le bloc paravertébral du plexus vertébral (PBPB) et sa version modifiée sont d’un grand intérêt pour toute procédure du membre thoracique, dans sa portion proximale. Toutefois, l’essentiel des données publiées à ce jour provient d’études colorimétriques, sans évaluation clinique, et peu d’information est disponible sur les techniques de localisation nerveuse envisageables à ce site. Notre étude visait à décrire une approche échoguidée du PBPB modifié, puis à caractériser ses paramètres pharmacocinétiques et pharmacodynamiques après administration de lidocaïne (LI) ou lidocaïne adrénalinée (LA). Huit chiens ont été inclus dans un protocole prospectif, randomisé, en aveugle et croisé, réparti sur trois périodes. L’impact pharmacodynamique du bloc effectué avec LI ou LA a été évalué régulièrement pour 180 min suivant son exécution. Le traitement à l’adrénaline n’a pas démontré d’impact significatif (P = 0,845) sur la durée du bloc sensitif, tel qu’évalué par un stimulus douloureux mécanique appliqué aux dermatomes ciblés. À l’opposé, l’atteinte proprioceptive évaluée par la démarche a été trouvée prolongée (P = 0,027) et le bloc moteur mesuré par le pic de force verticale (PVF) au trot sur la plaque de force s’est avéré plus marqué (PVF réduit; P = 0,007) sous LA. À l’arrêt comme au trot, le nadir de la courbe PVF-temps a été trouvé retardé (P < 0,005) et la pente ascendante de retour aux valeurs normales adoucie (P = 0,005). Parallèlement aux évaluations cliniques, des échantillons plasmatiques ont été collectés régulièrement afin de quantifier et décrire le devenir pharmacocinétique de la lidocaïne. Parmi les trois élaborés, un modèle bi-compartimental doté d’une double absorption asynchrone d’ordre zéro a finalement été sélectionné et appliqué aux données expérimentales. Sous LA, la Cmax a été trouvée significativement diminuée (P < 0,001), les phases d’absorption prolongées [P < 0,020 (Dur1) et P < 0,001 (Dur2)] et leurs constantes réduites [P = 0,046(k01) et P < 0,001 (k02)], le tout en concordance avec les effets proprioceptifs et moteurs rapportés. Bien que l’extrapolation du dosage soit maintenant théoriquement envisageable à partir du modèle mis en lumière ici, des études supplémentaires sont encore nécessaires afin d’établir un protocole de PBPB d’intérêt clinique. L’analyse sur plaque de force pourrait alors devenir un outil de choix pour évaluer l’efficacité du bloc dans un cadre expérimental.

Search for VHE gamma-ray emission from Geminga pulsar and nebula with the MAGIC telescopes

The Geminga pulsar, one of the brighest gamma-ray sources, is a promising candidate for emission of very-high-energy (VHE > 100 GeV) pulsed gamma rays. Also, detection of a large nebula have been claimed by water Cherenkov instruments. We performed deep observations of Geminga with the MAGIC telescopes, yielding 63 hours of good-quality data, and searched for emission from the pulsar and pulsar wind nebula. We did not find any significant detection, and derived 95% confidence level upper limits. The resulting upper limits of 5.3 × 10^(−13) TeV cm^(−2)s^(−1) for the Geminga pulsar and 3.5 × 10^(−12) TeV cm^(−2)s^(−1) for the surrounding nebula at 50 GeV are the most constraining ones obtained so far at VHE. To complement the VHE observations, we also analyzed 5 years of Fermi-LAT data from Geminga, finding that the sub-exponential cut-off is preferred over the exponential cut-off that has been typically used in the literature. We also find that, above 10 GeV, the gamma-ray spectra from Geminga can be described with a power law with index softer than 5. The extrapolation of the power-law Fermi-LAT pulsed spectra to VHE goes well below the MAGIC upper limits, indicating that the detection of pulsed emission from Geminga with the current generation of Cherenkov telescopes is very difficult.

Caractérisation pharmacocinétique et pharmacodynamique de la lidocaïne avec ou sans adrénaline lors d’un bloc paravertébral du plexus brachial chez le chien

Au cours des vingt dernières années, l’anesthésie régionale est devenue, autant en médecine vétérinaire qu’humaine, un outil essentiel à l’élaboration de protocoles analgésiques péri-opératoires. Parmi l’éventail de techniques mises au point en anesthésie canine, le bloc paravertébral du plexus vertébral (PBPB) et sa version modifiée sont d’un grand intérêt pour toute procédure du membre thoracique, dans sa portion proximale. Toutefois, l’essentiel des données publiées à ce jour provient d’études colorimétriques, sans évaluation clinique, et peu d’information est disponible sur les techniques de localisation nerveuse envisageables à ce site. Notre étude visait à décrire une approche échoguidée du PBPB modifié, puis à caractériser ses paramètres pharmacocinétiques et pharmacodynamiques après administration de lidocaïne (LI) ou lidocaïne adrénalinée (LA). Huit chiens ont été inclus dans un protocole prospectif, randomisé, en aveugle et croisé, réparti sur trois périodes. L’impact pharmacodynamique du bloc effectué avec LI ou LA a été évalué régulièrement pour 180 min suivant son exécution. Le traitement à l’adrénaline n’a pas démontré d’impact significatif (P = 0,845) sur la durée du bloc sensitif, tel qu’évalué par un stimulus douloureux mécanique appliqué aux dermatomes ciblés. À l’opposé, l’atteinte proprioceptive évaluée par la démarche a été trouvée prolongée (P = 0,027) et le bloc moteur mesuré par le pic de force verticale (PVF) au trot sur la plaque de force s’est avéré plus marqué (PVF réduit; P = 0,007) sous LA. À l’arrêt comme au trot, le nadir de la courbe PVF-temps a été trouvé retardé (P < 0,005) et la pente ascendante de retour aux valeurs normales adoucie (P = 0,005). Parallèlement aux évaluations cliniques, des échantillons plasmatiques ont été collectés régulièrement afin de quantifier et décrire le devenir pharmacocinétique de la lidocaïne. Parmi les trois élaborés, un modèle bi-compartimental doté d’une double absorption asynchrone d’ordre zéro a finalement été sélectionné et appliqué aux données expérimentales. Sous LA, la Cmax a été trouvée significativement diminuée (P < 0,001), les phases d’absorption prolongées [P < 0,020 (Dur1) et P < 0,001 (Dur2)] et leurs constantes réduites [P = 0,046(k01) et P < 0,001 (k02)], le tout en concordance avec les effets proprioceptifs et moteurs rapportés. Bien que l’extrapolation du dosage soit maintenant théoriquement envisageable à partir du modèle mis en lumière ici, des études supplémentaires sont encore nécessaires afin d’établir un protocole de PBPB d’intérêt clinique. L’analyse sur plaque de force pourrait alors devenir un outil de choix pour évaluer l’efficacité du bloc dans un cadre expérimental.

Hybrid Monte Carlo algorithm for the double exchange model

The Hybrid Monte Carlo algorithm is adapted to the simulation of a system of classical degrees of freedom coupled to non self-interacting lattices fermions. The diagonalization of the Hamiltonian matrix is avoided by introducing a path-integral formulation of the problem, in d + 1 Euclidean space–time. A perfect action formulation allows to work on the continuum Euclidean time, without need for a Trotter–Suzuki extrapolation. To demonstrate the feasibility of the method we study the Double Exchange Model in three dimensions. The complexity of the algorithm grows only as the system volume, allowing to simulate in lattices as large as 163 on a personal computer. We conclude that the second order paramagnetic–ferromagnetic phase transition of Double Exchange Materials close to half-filling belongs to the Universality Class of the three-dimensional classical Heisenberg model.

On the universality class of monopole percolation in scalar QED

We study the critical properties of the monopole-percolation transition in U(1) lattice gauge theory coupled to scalars at infinite (β = 0) gauge coupling. We find strong scaling corrections in the critical exponents that must be considered by means of an infinite-volume extrapolation. After the extrapolation, our results are as precise as the obtained for the four dimensional site-percolation and, contrary to previously stated, fully compatible with them.

Umbrella pine above ground biomass estimation with very high spatial resolution satellite images

Above ground biomass is frequently estimated with forest inventory data and an extrapolation method for the per unit area evaluations. This procedure is labour demanding and costly. In this study above ground biomass functions, whose independent variable is crown horizontal projection, were developed. Multi-resolution segmentation method and object-oriented classification, based on very high spatial resolution satellite images, were used to obtain the area of tree crown horizontal projection for umbrella pine (Pinus pinea L.). A set of inventory plots were measured and with existing allometric functions for this species above ground biomass per tree and per plot were calculated. The two data sets were used to fit linear functions both for individual plot and their cumulative values. The results show a good performance of the models. Errors smaller than 10% are obtained for stand areas greater than 1.4 ha. These functions have the advantages of estimating above ground biomass for all the area under study or surveillance, not requiring forest inventory; allow monitoring in short time periods; and are easily implemented in a geographical information system environment.

Above ground biomass estimation in Mediterranean multiple use systems with high spatial resolution satellite images

Forest biomass has been having an increasing importance in the world economy and in the evaluation of the forests development and monitoring. It was identified as a global strategic reserve, due to its applications in bioenergy, bioproduct development and issues related to reducing greenhouse gas emissions. The estimation of above ground biomass is frequently done with allometric functions per species with plot inventory data. An adequate sampling design and intensity for an error threshold is required. The estimation per unit area is done using an extrapolation method. This procedure is labour demanding and costly. The mail goal of this study is the development of allometric functions for the estimation of above ground biomass with ground cover as independent variable, for forest areas of holm aok (Quercus rotundifolia), cork oak (Quercus suber) and umbrella pine (Pinus pinea) in multiple use systems. Ground cover per species was derived from crown horizontal projection obtained by processing high resolution satellite images, orthorectified, geometrically and atmospheric corrected, with multi-resolution segmentation method and object oriented classification. Forest inventory data were used to estimate plot above ground biomass with published allometric functions at tree level. The developed functions were fitted for monospecies stands and for multispecies stands of Quercus rotundifolia and Quercus suber, and Quercus suber and Pinus pinea. The stand composition was considered adding dummy variables to distinguish monospecies from multispecies stands. The models showed a good performance. Noteworthy is that the dummy variables, reflecting the differences between species, originated improvements in the models. Significant differences were found for above ground biomass estimation with the functions with and without the dummy variables. An error threshold of 10% corresponds to stand areas of about 40 ha. This method enables the overall area evaluation, not requiring extrapolation procedures, for the three species, which occur frequently in multispecies stands.