Receptor Kinase THESEUS1 Is a Rapid Alkalinization Factor 34 Receptor in Arabidopsis

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Relocations and one-time disturbance fail to sustainably disperse non-breeding common ravens <Emphasis Type="Italic">Corvus corax</Emphasis> due to homing behaviour and extensive home ranges

Some protected species have benefited from human activities to a point where they sometimes raise concerns. However, gaps in knowledge about their human-related behaviour hamper effective management decisions. We studied non-breeding common ravens Corvus corax that aggregated and predated livestock in the surroundings of a landfill. Combining several approaches, we first assessed the effectiveness of relocations at distances ranging from 20 to 240 km, and of one-time disturbance consisting in non-lethal shots performed at night roosts and at surrounding foraging areas during two consecutive evenings, in reducing ravens’ presence at the landfill. Then, we documented the spatial ecology of both relocated ravens and control ones (i.e. released in situ). Although the return probability widely varied with relocation distance and time after release, homing behaviour (87/102 relocated ravens marked with wing tags [85.3%] returned to the landfill in 3 years) prevented relocations from sustainably reducing the presence of ravens. Likewise, one-time disturbance only decreased ravens’ abundance during a few hours. These results could be related to the extensive movements of ravens equipped with GPS trackers. The total area occupied by control ravens reached 40,492 km², i.e. 7.4% of the area of France and 21.7% of the French species distribution range. Individuals used smaller home ranges (min?=?84; max?=?1814 km²), consisting in a network of foraging areas and roosts that they visited. The daily and weekly turnover rates in the observed area of the landfill were high (on average 0.68?±?0.2 and 0.36?±?0.17, respectively) and the actual presence of ravens displayed strong seasonal variation. Hence, one-time/local management actions affected only a limited proportion of the population, partly explaining their small impact. Our study provides information needed to improve future management plans in a context of increasing ravens populations and conflicts with human activities.     

Fluctuations naturelles et évolution artificielle des biocénoses macrozoobenthiques intertidales de trois estuaires des côtes françaises de la Manche

The study of the intertidal benthic population dynamics in three estuaries of the English Channel (Baie des Veys, Seine estuary, Baie de Somme:France) brings to light two types of species:

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key-species which directly respond to the local disturbance of the environmental conditions in their densities (Spionidae, Capitellidae) and in their growth rates (Cerastoderma edule);

target-species such as Macoma balthica which can endure brief changes in the environmental factors and shows no sign of long-lasting consequences on its population dynamics; yet, it fully integrates long-term changes through its numbers and productivity.

The parallel between such a regular study of the seasonal variations on selected sites and various base line surveys allows the authors to discuss the COST 647 sampling programm in order to selectrms, range of temperature) from human disturbances (embankments, chemical pollution, eutrophication). Diverse hypothesis are suggested which bring about several research topics to be developed within a european cooperation.     

Changing time and emotions

In this paper, we consider that our experience of time (to come) depends on the emotions we feel when we imagine future pleasant or unpleasant events. A positive emotion such as relief or joy associated with a pleasant event that will happen in the future induces impatience. Impatience, in our context, implies that the experience of time up to the forthcoming event expands. A negative emotion such as grief or frustration associated with an unpleasant event that will happen in the future triggers anxiety. This will give the experience of time contraction. Time, therefore, is not exogeneously given to the individual and emotions, which link together events or situations, are a constitutive ingredient of the experience of time. Our theory can explain experimental evidence that people tend to prefer to perform painful actions earlier than pleasurable ones, contrary to the predictions yielded by the standard exponential discounting framework.     

Synthesis and structure–activity relationship of Huprine derivatives as human acetylcholinesterase inhibitors

New series of Huprine (12-amino-6,7,10,11-tetrahydro-7,11-methanocycloocta[b]quinolines) derivatives have been synthesized and their inhibiting activities toward recombinant human acetylcholinesterase (rh-AChE) are reported. We have synthesized two series of Huprine analogues; in the first one, the benzene ring of the quinoline moiety has been replaced by different heterocycles or electron-withdrawing or electron-donating substituted phenyl group. The second one has been designed in order to evaluate the influence of modification at position 12 where different short linkers have been introduced on the Huprine X, Y skeletons. All these molecules have been prepared from ethyl- or methyl-bicyclo[3.3.1]non-6-en-3-one via Friedländer reaction involving selected o-aminocyano aromatic compounds. The synthesis of two heterodimers based on these Huprines has been also reported. Activities from moderate to same range than the most active Huprines X and Y taken as references have been obtained, the most potent analogue being about three times less active than parent Huprines X and Y. Topologic data have been inferred from molecular dockings and variations of activity between the different linkers suggest future structural modifications for activity improvement.     

Gas permeability: a new quantitative method to assess endodontic leakage

Abstract Aim: The aim of this study was to evaluate a new endodontic leakage measurement method. Materials and methods: Permeability was assessed measuring the gas flow passing through the root. Positive and negative tests were carried out to assess the validity of the method. We used glass capillaries for calibration (diameters of 15, 30, 40, 50 and 75 mum). The applicability of the method was assessed with human teeth using three sealing methods: GuttaFlow (GF) and a single cone; Pulp Canal Sealer (PCS) and a single cone; PCS and system B. Results: This method demonstrated to be highly reproducible as the standard deviation was approximately 1% on average with glass capillaries. Significantly higher leakage (p<0.05) was recorded for endodontic treatment with GF and single cone compared to PCS and single cone and PCS with system B. Conclusion: Gas permeability is quantitative, sensitive, non-destructive and reproducible and seems appropriate for endodontic tests. It would participate in the indirect comprehension of leakage phenomena.     

A methacrylate embedding procedure developed for immunolocalization on plant tissues is also compatible with in situ hybridization.

A recently described method that uses methacrylate embedding of aldehyde fixed plant tissues allows the immunolabelling of a range of antigens (Baskin et al. 1992). We have tested whether the same embedding procedure is also compatible with in situ hybridization. For this purpose we have used 2- 5 μm sections of methacrylate embedded plantlets of Arabidopsis thaliana. After removal of the resin the sections were prepared for in situ hybridization following standard procedures. Three different digoxygenin (dig)-labelled probes were used, recognizing RNAs coding for the chlorophyll a/b binding protein cab-140, the β-tubulin tub5 and meri a member of the meri-5 family. Each of the probes shows the labelling pattern expected from the literature. Moreover, the method allows a good structural preservation of very fragile tissues, in contrast to paraffin embedding. We conclude that methacrylate embedding, allowing both immunolabelling and in situ hybridization with high resolution and structural preservation, offers a high potential for the functional analysis of genes and proteins in plant development. This is especially true for Arabidopsis thaliana, a widely used model species where it seems to be the method of choice.