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Twenty-first century remote sensing technologies are revolutionizing the study of tropical forests

The fields of tropical biology and conservation face significant transformations due to rapid technological developments in remote sensing. Other fields (e.g. Archeology) are experiencing this momentous change even more rapidly. In this article, we review some of the challenges that the fields of tropical biology and conservation face during the first quarter of the twenty-first century from the p

Quantifying changes on forest succession in a dry tropical forest using angular-hyperspectral remote sensing

The tropical dry forest (TDF) is one the most threatened ecosystems in South America, existing on a landscape with different levels of ecological succession. Among satellites dedicated to Earth observation and monitoring ecosystem succession, CHRIS/PROBA is the only satellite that presents quasi-simultaneous multi-angular pointing and hyperspectral imaging. These two characteristics permit the stu

Monitoring Flooding Damages in Vegetation Caused by Mining Activities Using Optical Remote Sensing

Ground removal during the mineral extraction in mine galleries provokes permanent changes in ground compacting during mine exploitation and after mine closure. In extreme cases, the loss of cohesion in ground layer over mines causes surface subsidence and eventually the emergence of flooded areas on the surface. Mining companies are obligated to the surveillance and mending of damages caused by th

Target detection of mine-related flooded areas using AISA-eagle data

The present research is developed in the frame of the R&D project GMES4Mining, which aims to support particular tasks within the different phases of a mining life cycle [1]. During the exploitation and after the closure of the mine, environmental and civil impacts may happen, due to changes in the compacting properties of the soil related to mining activities. In this paper, we focus in the em

Multi-Temporal Monitoring Of Ecological Succession In Tropical Dry Forests Using Angular-Hyperspectral Data (Chris/Proba)

The tropical dry forest is the largest and most threatened ecosystem in Latin America. Remote sensing can effectively contribute to the surveillance of conservation measurements and laws through the monitoring of natural protected areas, at the required temporal and spatial scales. CHRIS/PROBA is the only satellite that presents quasi-simultaneous multi-angular pointing and hyperspectral spectrosc

Light–dependent effects of zinc protoporphyrin IX on endothelium–dependent relaxation resistant to NoM–nitro–L–arginine

Acetylcholine (ACh) induces an Nω–nitro–L–arginine (L–NOARG)–resistant relaxation and hyperpolarization in the rat isolated hepatic artery. The possibility that carbon monoxide (CO) produced by haem oxygenase (HO) is an endogenous mediator of this response was investigated. Exogenously applied CO evoked a concentration–dependent relaxation, and the CO ‘scavenger’ oxyhaemoglobin (10μM) reduced the

The endothelium mediates a nitric oxide‐independent hyperpolarization and relaxation in the rat hepatic artery

The rat hepatic artery responds to acetylcholine (ACh) with an endothelium‐dependent relaxation, which is unaffected by nitric oxide (NO) synthase and cyclooxygenase inhibition. The purpose of this study was to investigate whether the NO‐independent relaxation is caused by hyperpolarization of the smooth muscle cells. In vessels with endothelium ACh induced a hyperpolarization in the presence of 0

Effects of ω‐conotoxin on adrenergic, cholinergic and NANC neurotransmission in the rabbit urethra and detrusor

The effects of ω‐conotoxin GVIA (an inhibitor of N‐type voltage‐operated calcium channels; VOCCs) were compared on adrenergic, cholinergic and non‐adrenergic, non‐cholinergic (NANC) responses induced by electrical field stimulation (EFS) in the rabbit urethra and detrusor. EFS induced a relaxation in urethral smooth muscle and lamina propria precontracted by arginine vasopressin (AVP). The relaxat

Calcium Antagonistic Properties of the Sesquiterpene T‐Cadinol and Related Substances : Structure‐Activity Studies

The calcium antagonistic properties of (+)‐T‐cadinol, some of its stereoisomers and related terpenes were investigated in both functional and radioligand binding studies, and the effects were compared with those of the dihydropyridine calcium antagonist (±)‐nimodipine. In the isolated rat aorta, the terpenes relaxed contractions induced by 60 mM K+ more potently than those induced by phenylephrine

Calcium Antagonistic Properties of the Sesquiterpene T‐Cadinol : A Comparison with Nimodipine in the Isolated Rat Aorta

Abstract: (+)‐T‐Cadinol is a sesquiterpene with smooth muscle relaxing properties. In the isolated rat aorta, T‐cadinol relaxed contractions induced by 60 mM K+ in a concentration‐dependent fashion. The dihydropyridine calcium antagonist nimodipine was approximately 4,000 times more potent than T‐cadinol. While both drugs nearly abolished the K+‐induced contractions, they only partially relaxed co

Inhibitory effects of the sesquiterpene T‐cadinol on contractile responses in the isolated guinea‐pig ileum

The smooth muscle relaxing effect of the sesquiterpene T‐cadinol, isolated from scented myrrh (resin of Commiphora guidottii Chiov., Burseraceae), was investigated. The compound inhibited the contractile responses in the isolated guinea‐pig ileum to histamine, carbachol, Ba2+ and K+ in a concentration dependent and reversible manner. The antagonism of the receptor‐mediated contractions induced by

Some substances with proposed digitalis-like effects evaluated on platelet functions sensitive for cardiac glycosides

1. 1. The effects of progresterone, corticosterone 21-acetate, chlormadinone acetate, dehydroepi-androsterone 3-sulfate and lysophosphatidylcholine were tested on 86Rb-uptake, 3H-5-HT-uptake, ADP-induced aggregation and 5-HT-induced shape change in human platelets. Ouabain and digoxin were used for reference. 2. 2. Ouabain and digoxin 10-5 M inhibited 86Rb-uptake by more than 85%, and chlormadinon

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Cette étude propose une analyse de la proportion d’élèves suédois qui étudientle français au collège et présente une réflexion plus générale sur la situationde l’enseignement du français en Suède. À partir de données statistiques de labase de données SIRIS, mise à disposition publique par la Direction nationale desÉtablissements scolaires, les résultats montrent que, même si la proportion d’élèves