Comparative morphology of the forewing base articulationin Sternorrhyncha compared with a representative of Fulgoromorpha (Insecta, Hemiptera)

The forewing articulation of single species from each of the four subgroups of Sternorrhyncha (Aleyrodomorpha, Aphidomorpha, Coccomorpha, Psyllomorpha) was examined by optical and scanning electron microscopy. The species were compared with a species of Cixiidae (Fulgoromorpha), as an outgroup of Sternorrhyncha. We present the results of a comparative analysis of the forewing articulation in these five groups, propose a standardized terminology and compare our findings with those previously reported. The wing base of all examined species is composed of the following structures: anterior and posterior notal wing process, first, second, and third axillary sclerites, tegula, and axillary cord. The number of elements included in the wing base and the surrounding area is the greatest in Cacopsylla mali, the most complicated species from Sternorrhyncha. Based on the shape of axillary sclerites and the number of elements forming the wing base environment, Orthezia urticae (Coccomorpha) and Cixius nervosus (Fulgoromorpha) are the most similar. Among Sternorrhyncha, the most similar axillaries are those of Aphis fabae and Orthezia urticae, which is congruent with existing classifications. In this paper we show that the four groups from Sternorrhyncha exhibit their own distinct wing base morphology

An iconic language for the graphical representation of medical concepts

<p>Abstract</p> <p>Background</p> <p>Many medication errors are encountered in drug prescriptions, which would not occur if practitioners could remember the drug properties. They can refer to drug monographs to find these properties, however drug monographs are long and tedious to read during consultation. We propose a two-step approach for facilitating access to drug monographs. The first step, presented here, is the design of a graphical language, called VCM.</p> <p>Methods</p> <p>The VCM graphical language was designed using a small number of graphical primitives and combinatory rules. VCM was evaluated over 11 volunteer general practitioners to assess if the language is easy to learn, to understand and to use. Evaluators were asked to register their VCM training time, to indicate the meaning of VCM icons and sentences, and to answer clinical questions related to randomly generated drug monograph-like documents, supplied in text or VCM format.</p> <p>Results</p> <p>VCM can represent the various signs, diseases, physiological states, life habits, drugs and tests described in drug monographs. Grammatical rules make it possible to generate many icons by combining a small number of primitives and reusing simple icons to build more complex ones. Icons can be organized into simple sentences to express drug recommendations. Evaluation showed that VCM was learnt in 2 to 7 hours, that physicians understood 89% of the tested VCM icons, and that they answered correctly to 94% of questions using VCM (versus 88% using text, <it>p </it>= 0.003) and 1.8 times faster (<it>p </it>< 0.001).</p> <p>Conclusion</p> <p>VCM can be learnt in a few hours and appears to be easy to read. It can now be used in a second step: the design of graphical interfaces facilitating access to drug monographs. It could also be used for broader applications, including the design of interfaces for consulting other types of medical document or medical data, or, very simply, to enrich medical texts.</p

Investigating determinants of yawning in the domestic (Equus caballus) and Przewalski (Equus ferus przewalskii) horses

International audienceYawning is rare in herbivores which therefore may be an interesting group to disentangle the potential function(s) of yawning behaviour. Horses provide the opportunity to compare not only animals living in different conditions but also wild versus domestic species. Here, we tested three hypotheses by observing both domestic and Przewalski horses living in semi-natural conditions: (i) that domestic horses may show an elevated rate of yawning as a result of the domestication process (or as a result of life conditions), (ii) that individuals experiencing a higher level of social stress would yawn more than individuals with lower social stress and (iii) that males would yawn more often than females. The study involved 19 Przewalski horses (PHs) and 16 domestic horses (DHs) of different breeds living in large outdoor enclosures. The results showed that there was no difference between the PH and DH in yawning frequency (YF). PHs exhibited much higher levels of social interactions than DHs. There was a positive correlation between yawning frequency and aggressive behaviours in PHs, especially males, supporting the idea that yawning may be associated with more excitatory/stressful social situations. A correlation was found between yawning frequency and affiliative behaviours in DHs, which supports the potential relationship between yawning and social context. Finally, the entire males, but not castrated males, showed much higher levels of yawning than females in both species. The intensity (rather than the valence) of the interaction may be important in triggering yawning, which could therefore be a displacement activity that helps reduce tension

Removal of arsenate from drinking water with a natural manganese oxide in the presence of competing anions

International audienceThe efficiency of arsenic removal from drinking water in adsorption processes using natural oxides may be influenced by the presence of other adsorbable anions. The present paper focuses on the study of arsenate adsorption by a natural manganese oxide. The objective is to determine which of the anions usually present in drinking water may be adsorbed: hydrogen carbonate, sulfate, chloride, nitrate, phosphate and arsenate. A kinetic batch experiment was conducted with a natural drinking water, leading to a first qualitative selection: nitrate and chloride have little interaction with the adsorbent, sulfate and hydrogen carbonate are adsorbed while phosphate and arsenate are strongly adsorbed. Then column experiments were run with aqueous solutions containing either chloride, sulfate, etc. The previous trends were confirmed and the equilibrium isotherms of the adsorbable anions were built by integration of the breakthrough curves. The isotherms fitted with a Langmuir model showed that the capacities were low (a few µmol.g-1). The affinity order was determined from the isotherm initial slopes: arsenate >> phosphate > hydrogen carbonate ≅ sulfate. Given the strong affinity of the adsorbent for arsenate and the low arsenate concentration in drinking water, the process selectivity for As traces from drinking water is ensured

Key parameters controlling an adsorption process for the selective removal of arsenic from drinking water

International audienceArsenic can be selectively removed from water through adsorption on a natural manganese oxide. This paper presents some of the key parameters controlling such a process. Both production and regeneration steps were studied and the influence of three main controlling parameters was put to light. The water pH greatly influenced the adsorption capacity. Low water pH highly improved the treatment. The adsorption being under mass transfer limitation, flow rate influence was measured and optimization solutions were proposed. Finally, the impact of the regeneration procedure was evaluated on the adsorbent stability. It gave good arsenic elution results but the caustic elution step generated fine particles that could not be avoided. The following neutralization could however be adjusted in order to minimize further adsorbent dissolution

Back-scattered electron visualization of ferroelectric domains in a BiFeO3 epitaxial film

Three-dimensional orientation of the ferroelectric (FE) domain structure of a BiFeO3 epitaxial film was investigated by scanning electron microscopy (SEM) using back-scattered electrons and piezoresponse-force microscopy (PFM). By changing the crystallographic orientation of the sample and the electron collection angle relative to the detector, we establish a link between the orientation of polarization vectors (out-of-plane and in-plane) in the BiFeO3 film and the back-scattered electron image contrast in agreement with PFM investigations. The different FE polarization states in the domains correspond to altered crystalline environments for the impingent primary beam electrons. We postulate that the resultant back-scattered electron domain contrast arises as a result of either differential absorption (through a channelling effect) or through back-diffraction from the sample, which leads to a projected diffraction pattern super-imposed with the diffuse conventional back-scattered electron intensity. We demonstrate that SEM can be sensitive for both out-of-plane and in-plane polarization directions using the back-scattered electron detection mode and can be used as a non-destructive and fast method to determine 3D FE polarization orientation of domains. Published by AIP Publishing

Identification and expression of water stress- and abscisic acid-regulated genes in a drought-tolerant sunflower genotype

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Control of binary states of ferroic orders in bi-domain BiFeO3 nanoislands

Understanding switching mechanisms in multiferroics such as BiFeO3 (BFO) is an important challenge to control ferroic orders (ferroelectric or ferroelastic) as it could lead to the design of non-volatile memories based on magnetoelectric coupling. Here, we demonstrate an alternative way to control the binary states of ferroic orders by locally applying pressure and electric field in ferroelectric bi-domains confined in single BFO nanoislands. The study of the electronic transport properties and domain orientations using atomic force microscopy (AFM) based techniques enabled us to determine the electric and mechanical parameters at which ferroelectric and ferroelastic resistive switching can be observed. Nanoislands exhibited binary high and low resistance states without scaling effect, with high performance switching characteristics. Positive-forward rectifying behavior at high tip force was interpreted by the formation of a subsurface non-conductive interface due to the strain gradient. Ferroelastic switching at the surface was associated with a symmetry-breaking induced by electromechanical coupling between the AFM tip and the BFO thin film. It led to out-of-plane polarization pinning that allows performing only in-plane switching accompanied by nucleation and propagation of a conductive domain wall. The control of ferroic binary states by the electric field and pressure may pave the way for multilevel data storage devices