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Secondary succession (SS) is one of the main consequences of the abandonment of agricultural and forestry practices in rural areas, causing -among other processes- woody encroachment on former pastures and croplands. In this study we model and monitor the spatial evolution of SS over semi-natural grassland communities in the mountain range of the Pyrenees in Spain, during the last 36 years (1984-2019). Independent variables for ‘annual-based’ and ‘period-based’ modeling were drawn from a suite of Surface Reflectance Landsat images, LandTrendr (LT)-algorithm-adjusted images and LT outputs. Support vector machine (SVM) classifiers were trained and tested using all possible variable combinations of all the aforementioned datasets. The best modeling strategy involved yearly time series of LT-adjusted Tasseled Cap Brightness (TCB) and Wetness (TCW) axes as predictors, attaining a F1-score of 0.85, a Matthew Correlation Coefficient (MCC) of 0.67 and an AUC 0.83. Woodlands encroached above 480,000 ha of grasslands and crops during the study period. A model using LT outputs for the whole period also denoted good performance (F1-score = 0.85, MCC = 0.75) and estimated a similar area of woodland expansion (~509,000 ha), but this ‘period’ approach was unable to provide temporal information on the year or the encroachment dynamics. Our results suggest an overall proportion of 66% for the Pyrenees being affected by SS, with higher intensity in the west-central part, decreasing towards the eastern end. This work was supported by project IMAGINE [CGL2016-80400-R] funded by the Spanish Science Foundation (FECYT) and by the research grant program Ajuts UdL, Jade Plus i Fundació Bancària La Caixa [Agreement 79/2018 of the Governing Council of the University of Lleida].

Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome-wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some populations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may constitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates. © 2019, The Author(s).

This report details the preliminary results of the research focused on Roman archaeological heritage in the Middle Ebro Valley (Spain). The principal objective of this project was to obtain several different readings by means of a UAV equipped with different sensors. Firstly, it has been possible to obtain accurate maps, 3D models and digital elevation models of the site. Secondly, it has been possible to investigate and define archaeological remains still underground, via a new methodology which utilises visible and near-infrared wavelengths.

An experimental work sampling study was performed using newly available technology in order to determine the allowance time of the task in the workday. In this study, heart rate measuring equipment was used on workers performing their activities during the work period while in parallel a traditional wok sampling study was performed. With this research it is possible to define a person's load work range (light, moderate and heavy) according to heart rate vs. activity performed, and on that basis, to determine the task allowance percentage. This proposed work sampling study method has better results for dynamic tasks, in other words when the operations require the entire body and/or walking.

Forest fires are one of the main factors transforming landscapes and natural environments in a wide variety of ecosystems. The impacts of fire occur both on a global scale, with increasing emissions of greenhouse gases, and on a local scale, with land degradation, biodiversity loss, property damage, and loss of human lives. Improvements and innovations in fire risk assessment contribute to reducing these impacts. This study analyzes the spatial variation in the explanatory factors of human-caused wildfires in continental Spain using logistic regression techniques within the framework of geographically weighted regression models (GWR). GWR methods are used to model the varying spatial relationships between human-caused wildfires and their explanatory variables. Our results suggest that high fire occurrence rates are mainly linked to wildland–agricultural interfaces and wildland–urban interfaces. The mapping of explanatory factors also evidences the importance of other variables of linear deployment such as power lines, railroads, and forestry tracks. Finally, the GWLR model gives an improved calculation of the probabilities of wildfire occurrence, both in terms of accuracy and goodness of fit, compared to global regression models.

La alteración de las propiedades del suelo y la destrucción de la cubierta vegetal son dos importantes consecuencias inducidas por el fuego. A escala regional, los datos de teledetección son adecuados para hacer un seguimiento de los procesos posteriores al fuego. Sin embargo, a nivel de suelo, las investigaciones sobre cambios en los valores de reflectividad son necesarias para conocer las relaciones entre las consecuencias medioambientales generadas por el fuego y los valores de reflectividad espectral. Las medidas tomadas por medio de un radiómetro de campo proveen información útil para describir estas relaciones. El principal objetivo de este estudio es caracterizar los patrones temporales de los valores de reflectividad en un fuego experimental y analizar las relaciones entre estos valores y los cambios inducidos en el suelo. Para ello se llevó a cabo la quema controlada de dos parcelas experimentales registrando con una frecuencia mensual los valores de reflectividad por medio de un espectrómetro de campo. Los datos recogidos han mostrado cómo la cubierta vegetal experimenta su mayor cambio en el momento del fuego presentando una gran estabilidad en el periodo posterior en ausencia de regeneración vegetal, mientras que el suelo desnudo es la cubierta con alteraciones más acusadas en su comportamiento a partir de la situación postfuego debido al incremento de los procesos de erosión.

Se analiza el impacto y la evolucion de la estructura del paisaje en un incendio del Prepirineo aragones utilizando 6 imagenes Landsat 5 TM, identificando relaciones entre valores de heterogeneidad espacial y comunidades vegetales. Se extraen los NDVI (Normalized Difference Vegetation Index), se calcula el indice de Shannon y se cartografia para cada ano. Se definen tres componentes representativos de los valores de diversidad (preincendio, a corto plazo y a medio plazo). Se concluye que a nivel de comunidad vegetal el incendio ha supuesto un incremento de la diversidad interna en algunas comunidades. No obstante, a medio plazo y a escala global el fuego provoca la homogeneizacion del paisaje, tal y como describen otros autores utilizando fuentes de informacion similar.

TerraSAR-X (TSX) dual-polarized synthetic aperture radar (SAR) data from a test site in Spain have been investigated to determine the relationship between forest burn severity and SAR backscatter. The role of the local incidence angle on the backscatter coefficient has been also studied. Burn severity was estimated by means of composition burn index plots and the remotely sensed differenced normalized burn ratio index. To infer the potential of the TSX data for burn severity assessment, the determination coefficients obtained from linear regression analysis have been used. At horizontal transmit horizontal receive (HH) polarization, backscatter increased for slopes oriented toward the sensor and areas affected by high burn severity, whereas, at horizontal transmit vertical receive (HV) polarization, higher backscatter occurred for slopes oriented away from the sensor in areas of low burn severity. The dependence of the backscatter coefficient on topography for areas affected by forest fire has been confirmed. The HH backscatter presented a clear descending trend with the increase in local incidence angle, whereas the HV backscatter presented an ascending trend. The determination coefficients showed that, at HH polarization, better estimates of burn severity are obtained at low local incidence angles, whereas, for HV polarization, the best estimates are obtained at high local incidence angles. The dual-polarized X-band SAR data showed potential for burn severity estimation in the Mediterranean environment if local incidence angle is accounted for.

Land-use decisions are usually made on the basis of a variety of criteria. While it is common practice to integrate economic, ecological and social (triple bottom line) criteria, explicit geoscientific factors are relatively rarely considered. If a planned land use involves an interaction with the geosphere, geoscientific aspects should be playing a more important role in the process. With the objective to facilitate a sustainable land-use decision-making a research project was initiated. The area around the city of Zaragoza, in the Ebro Basin of northern Spain, was chosen due to its high degree of industrialisation and urbanization. The area is exposed to several geohazards (e.g., sinkholes and erosion) that may have significant negative effects on current and future land uses. Geographical Information System (GIS) technologies are used to process the complex geoscientific information. Further GIS analysis comprised the creation of an erosion susceptibility map that follows the ITC (International Institute for Geo-Information Science and Earth Observation) system of terrain analysis. The agricultural capability of the soil was determined using the Microleis System. We identify geomorphologic units that show high susceptibility to erosion and high agricultural potential and suggest a method to implement this information in a land-use planning process. Degraded slopes developed upon Tertiary rocks show the highest susceptibility to erosion and low values of agricultural capability, whereas the flat valley bottoms and irrigated flood plains have the highest values of agricultural capability.

This study analysed medium-term degradation in Pinus sylvestris L. woodland affected by wildfire. To investigate recovery, a range of pedological (including thickness of the organic horizon, soil structure and texture, organic matter content, pH and the percentage of carbonates), geomorphological and vegetation parameters were assessed in comparable burnt and control plots. Main findings suggest that fire in the medium-term leads to severe degradation of P. sylvestris L. woodland ecosystems. The main consequences of the passage of fire are: (1) transformation of P. sylvestris L. woodlands into shrublands dominated by Genista scorpius (L.) DC, Buxus sempervirens L. and herbaceous species; (2) decrease in the thickness of the O horizon and its degradation and (3) increase in soil erosion features, due to the detachment of soil particles by rain-splash or overland flow and their transport downslope. These results could help to provide guidelines for the restoration of burnt areas to minimise the effects of wildfires. Copyright © 2009 John Wiley & Sons, Ltd.

Remote sensing has been shown to be an efficient tool in the study of forest-fire processes. However, a lack of information on the amount of biomass burnt reduces the accuracy of fire severity and emission models. In this study, we use imagery from the Landsat Thematic Mapper to map crown biomass and burn severity for a large Mediterranean area. Considering the specific characteristics of the Mediterranean environment, two methods to extract useful remote sensing data were employed; both sought to analyze relationships between crown biomass and spectral information. As a result, a crown biomass map of Pinus spp. was created for the entire study area, applying nonlinear regression using the variable MID57 (TM5 + TM7) (R2 = 0.651). Considering only P. halepensis pixels that were burnt in the selected fire scar, the relationships between crown biomass and burn severity were found to be high and significant, yielding an R2 value of 0.516. Finally, a logistic regression model was constructed to map the presence or otherwise of high burn severity levels using crown biomass as the independent variable, yielding in the confusion matrix an overall percentage of data points correctly classified of 77% and a Kappa statistic in the validation sample of 0.554.

Fire severity can be considered one of the most influential factors in the postfire development of burnt areas. Ground level studies documenting changes in reflectance values improve the discrimination of spatial fire severity across large areas. The objective of this study was to determine those spectral regions most sensitive to fire severity levels by investigating the relationship between postfire surface materials and reflectance values. A total of 34 field plots were analyzed immediately following two natural fires in Spain. To obtain postfire data, we used a portable structure to obtain vertical photographs and reflectance values in the visible-near-infrared (VIS-NIR) range. Spectral reflectance and convolved Landsat Thematic Mapper (TM) bands were statistically correlated with individual postfire materials and with a fire severity index, the Combustion Products Index (CPI), derived from them. The wavelengths most sensitive to postfire materials were 450.6, 758.2, and 797 nm for ash, black carbon, and vegetation, respectively, although these wavelengths were included within ranges of comparable behavior. Finally, stepwise multiple regression models (SMLRs) were applied to the data. SMLR predicted ash, black carbon, and vegetation levels from reflectance data with accuracies higher than 75%. Estimation from Landsat-TM bands yielded slightly lower accuracies. The CPI severity index was also well estimated using either reflectance data or TM bands (r 2 = 0.925 and r 2 = 0.840 , respectively).

In the surroundings of Zaragoza, karstification processes are especially intense in covered karst areas where fluvial terraces lie directly on Tertiary evaporites. Since the beginning of Quaternary, these processes have lead to the development of collapse and subsidence dolines with a wide range of sizes, which have significant economic impacts. To reduce economic impact and increase safety, a regional analysis of this phenomenon is needed for spatial management. Therefore, a probability map of dolines was developed using logistic regression and geographic information system (GIS) techniques. This paper covers the selection of input data, manipulation of data using the GIS technology, and the use of logistic regression to generate a doline probability map. The primary variable in the doline development in this area is geomorphology, represented by the location of endorheic areas and different terrace levels. Secondary variables are the presence of irrigation and the water table gradient.

The Quaternary deposits of the Ebro Basin in the surroundings of Zaragoza (Spain) form an unconfined alluvial aquifer with a high degree of permeability and low thickness of unsaturated materials. This fact causes a high degree of vulnerability to contamination, which implies consequences for land-use decisions and the risk management of existing industrial facilities. In addition, in the last decades the intense irrigation and the use of pesticides is threatening the quality of the groundwater and as a consequence the amount of usable groundwater at a low cost. Thus, the development of groundwater vulnerability maps has great importance in a regional planning process. Consequently, groundwater vulnerability maps have been developed following a method proposed by the German State Geological Surveys. In this paper the methodology developed within ArcGIS and Gocad, a two- and three-dimensional software, respectively, is presented. Although the results obtained within GIS (Geographical Information System) are acceptable it is to say that the 3D-model improves considerably the final product.

Summary We report a systematic collection of Triatominae inside houses and in the peridomestic environment of Alto Beni, department of La Paz, Bolivia. This area is free of Triatoma infestans and although we detected previously seropositivity for Trypanosoma cruzi, the Alto Beni region is not officially considered as endemic for Chagas disease. From 11 houses of five localities, we collected adults, nymphs and eggs of a Rhodnius species, which was confirmed by morphological and morphometric analysis as Rhodnius stali. This little-known species has long been confused with R. pictipes, and was originally described from museum specimens labelled as R. pictipes. Our data show that R. stali is able to establish colonies in domestic and peridomestic habitats in Bolivia, and it is probably the vector responsible for Chagas disease seropositivity observed in the indigenous population of Alto Beni.

A fructose-enriched diet induces an increase in blood pressure associated with metabolic alterations in rats. Our hypothesis was that an increase in protein kinase C (PKC) activation, reported in the acute period of fructose overload, and an impaired vessel's response to vasoactive substances contribute to maintain elevated blood pressure levels in the chronic period. The aims of this study were to investigate in this animal model of hypertension: (1) if the increase in PKC activation was also found in the chronic stage; (2) the involvement of nitric oxide and insulin in the vessel's response; and plasma atrial natriuretic factor and nitrites/nitrates (nitric oxide metabolites) behavior. We evaluated the effects of: PKC-stimulator 12,13-phorbol dibutyrate, phenylephrine, insulin, nitric oxide synthase-inhibitor NG-nitro-L-arginine methyl esther (L-NAME) and PKC-inhibitor Calphostin C on aortic rings responses of Sprague-Dawley rats: fructose-fed and control. The fructose-fed group showed higher contractility to 12,13-phorbol dibutyrate than the control group in aortic rings pre-incubated with insulin, and this difference disappeared with L-NAME. The response to phenylephrine in rings pre-incubated with Calphostin C was decreased in the fructose-fed group and increased with Calphostin C plus L-NAME. Fructose-fed rats showed higher levels of plasma atrial natriuretic factor and nitrites/nitrates than controls. In conclusion, chronic fructose feeding seems to develop an impaired response to insulin, dependent on nitric oxide, suggesting a PKC alteration. Vasorelaxant agents, such as atrial natriuretic factor and nitric oxide, would behave as compensatory mechanisms in response to high blood pressure.

Nitric oxide (NO) has been identified as an effective vascular relaxant. This study analyses the contribution of the precursor L-arginine (L-arg) by oral administration in two kidney-two clip hypertension in the rat (2K-2C). Two groups were studied: sham (SH, n=21) and hypertensive (HT, n=15). After 4 weeks of surgery, a group of rats remained as controls (SHc and HTc, respectively), while others were supplemented with L-arg (1.25 g/L) in drinking water (SHa and HTa) for 3 weeks. Blood pressure was significantly increased in 2K-2C rats but remained unchanged after L-arg treatment. Plasma nitrite/nitrate concentrations were not different among groups. The contractile response of aorta to KCl, serotonin and the protein kinase C (PKC) stimulant, phorbol 12,13-dibutyrate (PDBu) was also evaluated. Higher contractile responses to PDBu (p

Abstract —A fructose-enriched diet promotes hypertension in rats. We thought that an enhancement of the glycolytic and/or lipid disorder (s) that raise blood pressure could be the cause. Therefore, we studied 4 groups of Sprague-Dawley rats (±200 g): (1) control rats received a standard diet and tap water; (2) the glycerol group of rats received a standard diet and 0.54 mol/L glycerol in tap water; (3) the fructose group was given a fructose-enhanced diet (chow had 55% fructose instead of dextrin) and tap water; and (4) the fructose-glycerol group was given the fructose-enhanced diet and 0.54 mol/L glycerol in drinking water. At the end of the second week, the findings were as follows. Blood pressure was 149±2 mm Hg in the fructose-glycerol group versus 129±2 ( P P P P P P P P P 50 to 12,13-phorbol dibutyrate in the fructose-glycerol group than in the control ( P P P

European legislation calls for a well-planned sustainable development. As such, it has to in‐ clude a social, economic as well as an environmental dimension. According to Agenda 21 (http://www.un.org/esa/dsd/agenda21/), countries should undertake efforts to build up a comprehensive national inventory of their land resources in order to establish land informa‐ tion systems. The overall objective is to provide information for the improvement or the re‐ structuring of land-use decision processes including the consideration of socio-economic and environmental issues.

Regarding the three objectives of European Union (EU) energy policy (secure supply, competitiveness and environmental protection) the EU Commission published the Communication entitled ‘White Paper: Energy for the Future Renewable Sources of Energy’ (EU Commission, 1997; Mourelatou & Smith, 2004). This document, which was the starting point for the European promotion and development of renewable energy, stated the objective that 12% of energy production in 2010 would come from renewable sources. In Spain, this objective was recognized by the government in 1999 in the Plan to the Promotion of Renewable Energies (PPRE). To achieve this objective, the PPRE focused on increasing the use of biomass, identifying forest residues as one of the biomass sources. Specifically, this document established an increase in the use of forest residual biomass to 450 000 tonnes of petroleum equivalent per year (TPE/year) (IDAE, 1999). Among the different sources of renewable energy, this chapter focuses on forest residual biomass (FRB). This term refers to branches, foliage, and unmerchantable stem tops that are commercially unsuitable in terms of the timber obtained from regular operations in forest management or in timber exploitation (Esteban et al., 2004; IDAE, 1999; Velazquez, 2006). Following the ‘complete-tree concept,’ the term ‘branches’ include the wood and bark of live and dead branches; ‘foliage’ refers to all leaves-needles, new shoots and reproductive organs; and the ‘unmerchantable stem top’ is the upper section of the stem that is left unutilized in logging operations due to its small diameter and high degree of branching (the bottom stem diameter of this unmerchantable top usually ranges from 5 to 10 cm) (Hakkila & Parikka, 2002). The treatments commonly applied to these residues in Spain include controlled burning, stacking within the forest and, less commonly, splintering to improve their incorporation into the soil (IDAE, 2005a, 2007; Velazquez, 2006). However, this biomass segment can also be used as a source of energy in heating applications (fuel for domestic or industrial stoves and boilers) and in the generation of electricity (replacing fossil fuels in power stations) (Asikainen et al., 2002; IDAE, 2005b), with the majority of the residue currently being utilized for the latter in Spain (IDAE, 2007). The benefits associated with this energy-related use can be divided into two types: environmental and socio-economic. The first benefits are generated in the production phase, as the recovery and elimination of FRB reduces the risk of forest fires and their severity (IDAE, 2005a; Velazquez, 2006), and also because the implementation of silviculture can

[ES] Although post-fire soil erosion has been studied, little attention has been paid to changes in soil surface cover following fires, despite this being a key factor in understanding the water and sediment yield. This study, at Peñaflor (Spain), investigated the effect of fire on soil erosion using data from soil erosion plots and high spatial resolution photography (HSRP). Measurements were made from October 2003 to October 2005 in a control plot and a plot experimentally exposed to a fire in October 2004. Ground cover components were identified, including vegetation, bare soil, stones, charcoal and ash. Runoff and sediment concentrations were low because of the absence of intense rainfall events, but the fire contributed to an increase of soil erosion by one order of magnitude. HSRP observations demonstrated that the sediments become mixed with ash and charcoal. Disappearance of the ash two months after the fire and a reduction in the amount of surface charcoal showed that these factors control erosion during the first few rainfall events following a fire. An increase in rock fragment cover was a consequence of the removal of vegetation and litter by the fire, and removal of the ash and charcoal by overland flow. © 2011 Elsevier Ltd., This research has been financially supported by the Spanish Ministry of Science and Technology (grants CGL2008-01083/CLI and CGL2006-11619/HID). We thank Deborah Martin and two anonymous referees for reviewing and improving the draft manuscript.

Aging and gender are factors that affect the variation of physical work capacity. The present paper highlights the importance of the metabolism used by ergonomics to establish the appropriate limits of loads at work. This study compares the aerobic capacity of people from 20 to 71 years old split in 5 different groups. The laboratory experiment tested 33 volunteers (19 women and 14 men). A submaximal step test was used to measure the VO(2) using a portable breath by breath metabolic system and a telemetric heart rate monitor. Three methods to estimate the VO(2max) were compared: 1) a direct measurement of VO(2), 2) estimation by heart rate, and 3) a step test method using predetermined charts. Significant difference was encountered among the estimation methods as well as among the age ranges (F(2,92)=6.43, p

[1] Alterations in the hydrological cycle following wildfire due to the loss of ground cover vegetation and changes in soil properties have been documented in many studies. Nevertheless, the rapid process of vegetation recovery reduces such negative effects. Vegetation cover before fire, fire severity, and geophysical properties are important factors that control spatial discontinuities involved in the vegetation-covering process. The objective of this study was to estimate the probability of high erosion in order to map erosion-sensitive areas after fire. The analysis was carried out in different plant communities burnt by summer wildfires in the pre-Pyrenean area (Spain). Three-year Landsat Thematic Mapper (TM) images have been used for mapping wildfire areas and severity levels. Conversion to spectral reflectance has been applied for radiometric correction by normalizing topographic and atmospheric effects. Likewise, other physical variables have also been incorporated into the geographic information system (GIS): vegetation types, parent material, illumination, slope, aspect, and precipitation. The dependent variable has been characterized by means of fieldwork and a photointerpretation process based on high-resolution digital aerial orthophotographs taken 11-12 years after the fire. Different logistic regression models have been used for mapping the probability of erosion. Results indicate that prefire normalized difference vegetation index values and aspect are the most important variables for estimating erosion-sensitive areas after fire (Nagelkerke r2 = 0.66; Kappa values = 0.65). Finally, the use of nonparametric models with environmental digital information based on GIS can facilitate the management of burnt areas.

Toro Toro (T) and Yungas (Y) have been described as genetically well differentiated populations of the Lutzomyia longipalpis (Lutz & Neiva, 1912) complex in Bolivia. Here we use geometric morphometrics to compare samples from these populations and new populations (Bolivia and Nicaragua), representing distant geographical origins, qualitative morphological variation ("one-spot" or "two-spots" phenotypes), ecologically distinct traits (peridomestic and silvatic populations), and possibly different epidemiological roles (transmitting or nor transmitting Leishmania chagasi). The Nicaragua (N) (Somotillo) sample was "one-spot" phenotype and a possible peridomestic vector. The Bolivian sample of the Y was also "one-spot" phenotype and a demonstrated peridomestic vector of visceral leishmaniasis (VL). The three remaining samples were silvatic, "two-spots" phenotypes. Two of them (Uyuni and T) were collected in the highlands of Bolivian where VL never has been reported. The last one (Robore, R) came from the lowlands of Bolivia, where human cases of VL are sporadically reported. The decomposition of metric variation into size and shape by geometric morphometric techniques suggests the existence of two groups (N/Y/R, and U/T). Several arguments indicate that such subdivision of Lu. longipalpis could correspond to different evolutionary units.

Previous studies from our own laboratory have shown that abdominal aorta rings from two kidney - two clip hypertensive rats (HT) develop hypersensitivity to serotonin (SER) which is related to a decreased nitric oxide (NO) availability and enhanced thromboxane A2 production. In the present study we investigated whether calcium and prostanoid-NO interactions are involved in these findings. To this purpose, the aortic responses to SER were analyzed in calcium-free medium and in calcium-depleted aorta placed in normal medium. Moreover, effects of ridogrel (RID, an antagonist of TxA 2/PGH2 receptors and inhibitor of thromboxane synthetase) were analysed by cumulative dose-response curves to SER in the presence and in the absence of the NO synthase inhibitor N(omega)-nitro-L-arginine (NOLA). Vascular responses to SER in vessels from HT rats were associated with increased intracellular calcium mobilization. In addition, hypersensitivity to SER in HT group respect to sham group (SH) disappeared in the presence of RID, NOLA and RID plus NOLA. RID decreases the maximum tension to SER and this effect was prevented by NOLA. This inhibition was of a greater magnitude in rings from sham rats (SH): 34 +/- 6% than in HT rats: 15 +/- 6% (p < 0.05). Besides, RID decreased the sensibility to SER in the presence of NOLA only in the HT group. In conclusion, the present study suggests that SER hypersensitivity observed in HT rats is related to a facilitated intracellular calcium mobilization and enhanced TxA2-endoperoxide response. Changes in membrane SER-gated calcium channels opening are observed only during the early hypertensive period. Besides, the lower depressor effect of RID on the maximal tension to SER in aorta rings from HT rats are related with a decreased NO availability in this model of renovascular hypertension.

International audience; Wings of a Rhodnius specimen from Alto Beni (Bolivia) was examined for identification and compared with R. stali, R. robustus, (certified Bolivian species), R. pictipes and R. prolixus (suspected Bolivian species). A projection of the unidentified wings as supplementary data into a discriminant analysis of shape revealed clear cut differences with R. stali and R. pictipes, less differences with R. prolixus, and none with R. robustus. Combining global size and shape of the wings, the unknown specimen was identified as R. robustus. Thus, this study confirmed the presence of R. robustus in Bolivia. It also highlighted the possibility of morphometrics to taxonomically interpret one individual, or even one piece of an individual, when related species data are available for comparison.

International audience; This is the first report of adult and nymphs (20 nymphs of all stages and 4 adults) of Microtriatomatrinidadensis (Lent 1951) (Hemiptera: Reduviidae: Triatominae) collected in peridomestic environment,in the department of La Paz, Bolivia.These specimens were associated to Rhodnius stali Lent, Jurberg & Galvão 1993. The exceptionalfinding of M. trinidadensis in peridomestic environment, illustrates the general tendency of triatominaeto adapt to human dwellings and dependences.

Hig levels of circulating atrial natriuretic factor (ANF) have been reported in several physiopathologic conditions like hypertension, heart and renal failure, pregnancy and high sodium intake. Nevertheless, neither relationships with water-sodium space regulation nor the role of an ANF vascular relaxant effect have been yet defined. The aim of present experiments was to characterize the contribution of circulating ANF and its vascular relaxing effects in the two kidney-two clip (2K2C) experimental model of renovascular hypertension. Complementary, plasma metabolites nitrite/nitrate of nitric oxide (NO) was examined because of mediation for both (NO an ANF) through cGMP. Three results showed (two-four weeks after surgery): indirect systolic blood pressure (mmHg), 186 +/- 4 in HT and 122 +/- 1 in SH (p0.001); a significant increase of plasma ANF (fmol/ml) in HT (n = 7, 1221 +/- 253) vs. SH (n = 9, 476 +/- 82; p0.02). Nitrate/nitrite plasma concentrations (mumol/l) were mpt different between SH and. The relaxant effect of ANF (10(-9), 10(-8) and 10(-7) M) on phenylephrine (3,5 x 10(-6) M) contracted rings from HT rats was smaller than SH rats (10(-8) M, p0.05). Contractions to phorbol 12, 13-dibutyrate (seven weeks after surgery) were significantly higher in rings from HT rats (p0.001). We conclude: 1) in addition to decreased granularity in atrial myocardiocytes, high circulating values of ANF here described suggest an increased turnover of the peptide in 2K2C hypertensive rats; 2) lower significant vascular relaxant effects in HT rats would indicate down regulation of ANF receptors in this model; the latter would derive from high plasma ANF concentration and, tentatively, because of greater activity of protein kinase C in the vascular wall; 39 similar values of plasma nitrite/nitrate in SH and HT rats would indicate a comparable NO circulating availability in both groups.

Fire risk assessment should take into account the most relevant components associated to fire occurrence. To estimate when and where the fire will produce undesired effects, we need to model both (a) fire ignition and propagation potential and (b) fire vulnerability. Following these ideas, a comprehensive fire risk assessment system is proposed in this paper, which makes extensive use of geographic information technologies to offer a spatially explicit evaluation of fire risk conditions. The paper first describes the conceptual model, then the methods to generate the different input variables, the approaches to merge those variables into synthetic risk indices and finally the validation of the outputs. The model has been applied at a national level for the whole Spanish Iberian territory at 1-km2 spatial resolution. Fire danger included human factors, lightning probability, fuel moisture content of both dead and live fuels and propagation potential. Fire vulnerability was assessed by analysing values-at-risk and landscape resilience. Each input variable included a particular accuracy assessment, whereas the synthetic indices were validated using the most recent fire statistics available. Significant relations (P < 0.001) with fire occurrence were found for the main synthetic danger indices, particularly for those associated to fuel moisture content conditions.

The heart has an endocrine activity which depends on the secretion of a natriuretic, diuretic and hypotensive factor contained in osmophilic, secretory granules localized in the myocardiocytes and called "atrial specific granules" (the atrial natriuretic factor, ANF). In this paper, the relationship between these specific granules and renovascular hypertension elicited by the constriction of both renal arteries was investigated at the electron microscope level during the acute, subacute and chronic phases of hypertension. Male Wistar CHbb THOM rats were divided in three groups: 1) clipped rats; 2) sham operated rats; 3) ether anesthesia as unique manoeuver 48 h before decapitation. Blood pressure increased progressively after the constriction of both renal arteries. The atrial specific granules were not affected by ether anesthesia alone; 48-72 h after clipping the granules almost disappeared and this situation persisted up to the 6th week. In sham operated rats the picture was very similar to the clip rats 48 and 72 h after surgery (severe granule disappearance); in contrast, at one, two and six weeks after surgery, the granularity of cardiomyocytes in sham rats was absolutely restored. It is concluded that: 1) similarities in morphology of atrial specific granules in sham and clip rats 48 and 72 h after surgery would suggest that stress plays a primary role in determining the observed images; 2) thereafter, the contrast between sham and clip rats 1, 2 and 6 weeks after surgery would indicate that the ANF is linked to the subacute and chronic regulation of renovascular hypertension.

These experiments have analyzed: a) Blood pressure (BP) and renal function in one kidney-one clip rats two weeks after clipping; b) The effect of cycloxygenase (CO) inhibition on BP and renal function regulation during the hypertensive period. Using the unanaesthetized, unrestrained and chronically instrumented animal, three groups of rats were studied: Sham, Clip 0.31 mm lumen and Clip 0.29 mm lumen. The animals were examined before (Control period) and during the infusion of indomethacin (IND, 5 mg/kg via aortic cannula, n = 11 for each group) or the buffer vehicle solution (BUF, n = 7 for each group). Effective inhibition of CO by IND was confirmed using radioimmunoassay of prostaglandin E2 (PGE2) in urine. Control BP (mmHg, mean +/- SE) differed significantly among the groups (p0.001): Sham, 114 +/- 3; Clip 0.31, 135 +/- 2; Clip 0.29, 154 +/- 4 and did not change by IND infusion. Along with the BP, Control Glomerular Filtration Rate and Renal Plasma Flow did not change by IND infusion, which suggests that CO eicosanoids, particularly PGG2, contribute little to basal renal hemodynamics in sham and hypertensive rats. Sodium excretion was lower in the Control period of Clip 0.29 rats (p0.01). A significant natriuretic effect observed in this Clip 0.29 group by the infusion of IND suggests the contribution of an AA related metabolite in renal handling of sodium in more severe renovascular hypertension.

Forest fire represents a major agent promoting changes at the landscape level and increasing land degradation risk. The ecological vulnerability to fire can be defined as the susceptibility of the ecosystem to be changed as a consequence of fire. Environmental features, as well as vegetation structure (composition and frequency), are key factors to estimate that vulnerability. The incorporation of GIS and remote sensing opens the possibility of cartographical approaches and temporal analysis, being necessary the development of new methodologies for the evaluation of the vulnerability to fire. This work shows a methodological approach to evaluate the ecological vulnerability to fire in two areas: Valencia (E Spain) and Aragon (inland N Spain), considering the available cartographical information, and being supported by GIS and remote sensing. The analysis of ecological vulnerability has been structured in different stages: at shortterm (focussed on soil degradation risk), at medium-term (focussed on changes in plant composition and structure), and coupling the short and medium-term vulnerabilities. The variables to be considered must be obtained and/or expressed in cartographical format. The sensitivity degree for every factor was divided in three categories: high (H), medium (M) and low (L). The factors were integrated applying a matrix method. For the short-term vulnerability, we considered the next environmental factors: rainfall aggressiveness (categories based on maximum rainfall intensity in 24 hours, return period 10 years), slope steepness and a soil erodibility factor (integrating lithological maps with organic matter estimations, the latter based on vegetation maps and remote sensing). We considered that post-fire soil degradation will be modulated by the time of exposure of the soil surface to the environmental factors. According to that, the integration of environmental factors was put together with an estimation of the response capacity of the vegetation. This classification was based in the dominant reproductive strategy (frequency of seeder and resprouter species), water constraints (in relation to the length of the dry period and the slope aspect) and fire frequency (that can influence the soil seed bank and the resprouting capacity). At medium-term, the ecological vulnerability was determined by the capacity of the community to return after fire to the pre-fire conditions without significant changes in composition and structure (resilience). This capacity was associated with the presence/dominance of species with different reproductive strategies, structure of the community and fire frequency. Environmental data was obtained from climatic maps, records from a network of weather stations and digital elevation model. Fire frequency was obtained from forest services, aerial photography and remote sensing analysis. In order to cartographical classification of vegetation communities, the categories must be based on functional attributes related to response capacity to fire, being the Forest Map of Spain (digital format) the most accurate and applicable source. The first step was gathering vegetation V International Conference on Forest Fire Research D. X. Viegas (Ed.), 2006 classes as homogenous as posible according to the main species reflected on the Forest Map of Spain, validated with field work.