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Simple Summary: The objective of the present study was to compare the incidence of and mortality due to plasmacytoma and multiple myeloma in French Guiana with mainland France and with Latin American countries, and to determine whether the epidemiological profile in our territory was South American or European. The incidence of these tumors was higher in French Guiana than in other countries in Latin America. The incidence has increased in the past decade, especially among women. The underlying explanation may be a large population with African ancestry and a high prevalence of obesity in our territory, particularly among women. Background: The objective was to review a decade of plasmacytoma (PC) and multiple myeloma (MM) data from French Guiana, and to study its spatial and temporal trends. Methods: This was a retrospective study of MM and PC between January 2005 and December 2014 using cancer registry data, including age-standardized incidence and mortality rates. Results: There were 110 cases of PC and MM (62 women and 48 men), representing the eighth most frequent malignancy in French Guiana. PC and MM were much more common in females. In men, 79% of cases occurred at ≥55 years, and in women, 90% of cases occurred at ≥50 years. The median age at diagnosis was 60 years for men and 66 years for women, while it was 72 years for men and 75 years for women in mainland France. The incidence rate standardized to the world population was 5.9 patients of PC and MM per 100,000 men/year and 7.8 per 100,000 women/year. Conclusions: In our territory, the incidence of PC and MM was higher and patients were diagnosed at a substantially younger age than in mainland France. Women had a greater incidence than men, and there was an increasing temporal trend of incidence among women. African ancestry and the frequency of obesity, notably among women, could have contributed to this observation. [ABSTRACT FROM AUTHOR]

Structural and elastic properties of InN in both B4 (wurtzite) and B1 (rocksalt) phases are studied over a wide range of pressures from 0 to 20 GPa at T = 0 K, using the density functional perturbation theory (DFPT) for the first time. Pressure dependencies of the total energy, structure parameters, elastic stiffness constants c ij , bulk modulus, Kleinman internal strain parameter, shear anisotropies and their relationship to elastic stability are also explored. In addition, the aggregate elastic modulus (B, G, E), Poisson's ratio (ν) and Lame's coefficients (λ) are estimated within the framework of Voigt–Reuss–Hill approximation for ideal polycrystalline InN aggregates, and thus the longitudinal and transverse sound velocities are obtained. We estimated the Debye temperature ΘD(T), energy E(T), entropy S(T), free energy F(T), and lattice heat capacity c v (T) as a function of temperature at null pressure for B4 (wurtzite) phase. Our results are in reasonable agreement with the available theoretical and experimental data for B4 phase. To our knowledge this is the first quantitative theoretical prediction of the B1 (rocksalt) that is still awaiting experimental confirmations. [ABSTRACT FROM AUTHOR]

In this work, the effect of pressure on the electronic band structure, partial density of states (PDOS), and the band gap of the four phases of ZnO, namely B4 (wurtzite), B3 (zinc-blende), B1 (rocksalt) and B2 (CsCl-type), has been investigated using the plane-wave pseudo-potential code CASTEP with three different schemes: the generalized gradient approximation (GGA) in the latter approach Perdew–Burk–Ernzerhof (PBE) with and without spin–orbit (SO) coupling, the new hybrid exchange–correlation functional named B3LYP functional and Hartree–Fock + Local Density Approximation (HF + LDA). These schemes are employed in order to treat the exchange–correlation effects. In addition, we will illustrate how the orbital motion of crystal electrons is affected by spin–orbit (SO) coupling. To our knowledge, this is the first theoretical study reported on ZnO using the B3LYP method. Our investigation shows that the increase of the pressure causes the nature of the band gap to change from direct to indirect. The mechanism responsible for this change of band structure is analyzed. The wide band gap of the B4 (wurtzite) phase at p = 0 as determined by the precedent methods is ∼3.221 and 3.222 eV (PBE) with and without spin–orbit (SO) coupling, respectively, 9.186 eV (HF + LDA) and 2.451 eV (B3LYP). The first two approaches provide the best agreement with the experiments. The band gap of B3 (zinc-blende), B1 (rocksalt) and B2 (CsCl-type) and the strong contribution of d orbitals of Zn atoms on the structure of the bands will be discussed. The SO coupling effect on the band structure for all phases is presented. This effect on the electronic properties of the various phases of ZnO in particularly for the B3 (zinc-blende), B1 (rocksalt) and B2 (CsCl-type) phases at high pressures are not well-known. The aim of this work is to improve the DFT band gap error by introducing different schemes and therefore this study is important for future experimental work on this potential semiconductor material. In this study we have shown the effect of SO coupling on the bands structure of ZnO as a function of pressure, and analyzed the mechanism of this effect. The understanding of spin–orbit coupling related phenomena is very important in both fundamental research and in applications of semiconductors systems. [ABSTRACT FROM AUTHOR]

Abstract: The structural, electronic and vibrational properties of InN under pressures up to 20GPa have been investigated using the pseudo-potential plane wave method (PP-PW). The generalized-gradient approximation (GGA) in the frame of density functional theory (DFT) approach has been adopted. It is found that the transition from wurtzite (B4) to rocksalt (B1) phase occurs at a pressure of approximately 12.7GPa. In addition, a change from a direct to an indirect band gap is observed. The mechanism of these changes is discussed. The phonon frequencies and densities of states (DOS) are derived using the linear response approach and density functional perturbation theory (DFPT). The properties of phonons are described by the harmonic approximation method. Our results show that phonons play an important role in the mechanism of phase transition and in the instability of B4 (wurtzite) just before the pressure of transition. At zero pressure our data agree well with recently reported experimental results. [Copyright &y& Elsevier]

Abstract: A cerium oxide thin layer was electrodeposited onto stainless steel, using mixed room temperature ionic liquid (the 1-methyl-3-butylimidazolium bis(trifluoromethyl sulfonyl)imide)/ethanol solutions, as electrolytic medium. The hydrophobic ionic liquid content is one of the main parameters in the morphology control influencing the ceria growth rate and crystallinity. Micro-nano structural properties and electrical behaviour are presented, using XRD, SEM/EDS and impedance spectroscopy, as a function of electrodeposition conditions. [ABSTRACT FROM AUTHOR]

Identifying the proximate basis of heterospecific matings in hybrid populations could significantly advance our understanding of mate recognition. As females are often considered to be the more selective sex, most studies have focused only on female mate choice. However, male behaviour often plays a determinant role in sexual selection. In the European waterfrog hybridization complex, the unbalanced mating frequency observed between hybrid females Rana esculenta and the parental species Rana lessonae has been attributed to a preference of these females for heterospecific males. In this study, for the first time we investigated the behaviour of males from three taxa (two parental species and the hybrid) in natural choruses. It appears that the three waterfrog taxa differ in their mating behaviour. We found that the breeding behaviour of R. lessonae males (i.e. low-frequency territorial call, close intermale proximity, movement not limited to a small area) suggests that they do not defend any territory. This constitutes evidence that R. lessonae males compete to outrace rivals to receptive females. Apart from the acoustic behaviour that appears to be intermediate between that of the two parental species, the other behavioural traits of the hybrid resemble those of the parental species Rana ridibunda (aggressive and territorial behaviours). These results suggest a genetic basis to these complex behavioural traits. From an ecological point of view, we conclude that the strong under-representation of hybrid males observed in amplexus can be due to the maladaptive hybrid reproductive tactic in mixed choruses. [Copyright &y& Elsevier]

Abstract: The ion transfer reaction across liquid|liquid interface present at carbon paste electrode prepared with hydrophobic room temperature ionic liquid (RTIL)-1-decyl-3-methylimidazolum bis(trifluoromethylsulfonylimide) as a binder is reported. Ion transfer was forced by generation of tert-butylferrocenium cation from neutral substrate present in RTIL phase. This process exhibits selectivity towards hydrophobic anions like or and it is more efficient than in the case of carbon paste electrode based on polar solvent. [Copyright &y& Elsevier]

The success and the evolutionary fate of hybridogenetic lineages are explained by both a generalistic heterosis hypothesis and an alternative hypothesis, the habitat segregation hypothesis. Because such hypotheses have rarely been tested at the level of whole habitats, our aim was to compare performances of two taxa within a hybridogenetic complex across diverse natural habitats. We took advantage of the waterfrog hybridogenetic complex ( Rana esculenta and R. lessonae) by rearing tadpoles in natural contrasted habitats by means of enclosure experiments. We also monitored the frequency of each taxon in the waterfrog assemblages that naturally breed in the studied ponds. The hybridogenenetic taxon showed no evidence of broader tolerance as growth, development and physiology strongly varied in response to environmental heterogeneity. Our study reveals a differential success of the hybridogenetic taxon and its sexual host among environments. Moreover, hybridogenetic taxa rarely dominated the sexual species in natural assemblages. Consequently, our results show that the generalistic model does not explain the success of hybridogenetic lineages, but rather support the habitat segregation, among other alternative concepts. [ABSTRACT FROM AUTHOR]

Abstract: Orchard vigour, defined as the intensity of vegetative growth, is an important indicator for crop management in fruit tree cropping systems. It is often evaluated in commercial plots by experts on a non-formalised basis or measured with a single variable known as trunk cross-sectional area (TCSA). In this article, we proposed a set of 11 tree or plot morphological vegetative variables for apple orchards and applied it on 117 farm plots in south-eastern France. Relationships between variables were studied by component analysis (CA) and plots were classified into four clusters according to the first two factors of the CA. These modelled vigour marks were compared to expert vigour marks on 14 plots. Plot modelled vigour classification was re-estimated with only three morphological variables and compared to the original classification. These morphological variables were: TCSA, number of water sprouts on the trunk and length of annual shoot at the distal part of fruiting branches at the bottom of the tree. The first three factors of the CA correspond to vegetative growth intensity, opposition between annual and cumulative growth and vigour balance, respectively. Modelled and expert plot vigour classifications were generally in agreement, except in the case of heterogeneous plots. Re-estimated and original modelled classifications were also in agreement, except in the case of older and more vigorous orchards. Results showed that plot vigour modelling based on these three morphological variables may be relevant. TCSA thus did not appear to be sufficient. Results are discussed in relation to plant architecture features. [Copyright &y& Elsevier]

Induced defences, such as the predator avoidance morphologies in amphibians, result from spatial or temporal variability in predation risk. One important component of this variability should be the difference in hunting strategies between predators. However, little is known about how specific and effective induced defences are to different types of predators. We analysed the impact of both pursuing (fish,Gasterosteus aculeatus) and sit-and-wait (dragonfly,Aeshna cyanea) predators on tadpole (Rana dalmatina) morphology and performance (viz locomotive performance and growth rate). We also investigated the potential benefits of the predator-induced phenotype in the presence of fish predators. Both predators induced deeper tail fins in tadpoles exposed to threat of predation, and stickleback presence also induced longer tails and deeper tail muscles. Morphological and behavioural differences resulted in better escape ability of stickleback-induced tadpoles, leading to improved survival in the face of stickleback predation. These results clearly indicate that specific morphological responses to different types of predators have evolved inR. dalmatina. The specific morphologies suggest low correlations between the traits involved in the defence. Independence of traits allows prey species to fine-tune their response according to current predation risk, so that the benefit of the defence can be maximal. [ABSTRACT FROM AUTHOR]

The impact of multiple factors on the expression of phenotypic plasticity has been poorly studied. The simultaneous presence of factors inducing diverging responses may result either in a trade-off between the responses or in a hierarchy of responses. Inducible defenses offer a suitable model to investigate these alternatives. Inducible defenses evolve in response to variability in predation risk. Here, we investigated the impact of the nonlethal presence of both pursuing (fish, Gasterosteus aculeatus) and sit-and-wait (dragonfly larvae, Aeshna cyanea) predators on tadpole morphology in two frogs (Rana dalmatina and R. ridibunda). Predation tests showed that Aeshna were the more dangerous of the two predators for the tadpoles of both species. In both species, induced responses differed according to predator type. In the presence of fish, tadpoles invested in both tail muscle depth and tail length. In the presence of dragonfly larvae, the investment was made in tail fin depth. When faced with the two types of predators simultaneously, the response was similar to that expressed in the presence of Aeshna alone, suggesting a hierarchy of response according to predation risk. Such a hierarchy of response could result from se- lection against the phenotype induced by the other predator. [ABSTRACT FROM AUTHOR]

This work aims to explore in the field the relationship between the integrity of sperm DNA and the quality of offspring as a possible cause of the decline of a feral fish population through reproduction impairment. Mature nase ( Chondrostoma nasus ) were caught during the breeding season in three locations (A–C) of the Rhône River basin and gametes collected by stripping. Sampling locations were chosen according to the following gradient of contamination due to human activities on the watershed: A ≤B < C. Samples of a pool of collected oocytes were fertilized with the sperm of individual males and then incubated individually back in the lab to study embryo-larval development as well as using sperm samples to assess DNA integrity. Genetic analysis clearly showed the absence of a difference in genetic structure between the three studied C. nasus populations from the Rhône basin. Sperm DNA integrity was significantly lower in males from station C compared to other ones while sperm biochemical characteristics and fertilization rate remained almost unchanged whatever the station. Mortality and abnormality rates measured at both hatching and at the end of yolk sac resorption stages followed the same trend as the sperm DNA damage, demonstrating an impact of river water quality on nase fitness through a loss of sperm DNA integrity. Since the level of both abnormalities and mortality measured in offspring of fish caught in the most contaminated area reached high values up to 15% and 80%, respectively, the hypothesis that the observed nase decline in Rhône River stemming through selection forces can be put forward. [ABSTRACT FROM AUTHOR]

Abstract: We report on the strong coupling between surface plasmons and inorganic quantum well excitons. The sample is formed by a corrugated silver film deposited on the top of a heterostructure consisting of five GaAs/GaAlAs quantum wells grown by molecular beam epitaxy. Reflectometry experiments at low temperature (77 K) evidence the formation of plasmon/heavy-hole exciton/light-hole exciton mixed states. The interaction energies, deduced by fitting the experimental data with a coupled oscillator model, amount to 22 meV for the plasmon/light-hole exciton and 21 meV for the plasmon/heavy-hole exciton. Some particularities of the plasmon–exciton coupling are also discussed and qualitatively related to the plasmon polarization. [Copyright &y& Elsevier]

Abstract: TiO2 thin films were prepared by sol-gel method. The structural investigations performed by means of X-ray diffraction (XRD) technique and scanning electron microscopy (SEM) showed the shape structure at T =600°C. The optical constants of the deposited film were obtained from the analysis of the experimentally recorded transmittance spectral data in the wavelength of 200–3000nm range. The values of some important parameters of the studied films are determined, such as refractive index n and thickness d. In this work, using the transmission spectra, we have calculated the dielectric constant (ε ∞) for four layered TiO2 films; a simple relation is suggested to estimate the third-order optical nonlinear susceptibility χ (3). It has been found that the dispersion data obeyed the single oscillator of the Wemple–DiDomenico model, from which the dispersion parameters and high-frequency dielectric constant were determined. The estimations of the corresponding band gap E g, χ (3) and ε ∞ are 2.57eV, 0.021·10−10 esu and 5.20, respectively. [Copyright &y& Elsevier]

Abstract: A thin film of carbon nanofibers embedded into a hydrophobic sol–gel material and deposited onto tin-doped indium oxide substrate electrodes is employed as a support for liquid|liquid redox systems. The system 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide|aqueous electrolyte is studied with t-butylferrocene as an electrochemically active component in the ionic liquid phase. Redox processes within the ionic liquid are coupled to ion transfer processes at the ionic liquid|water interface. The carbon nanofiber electrode material provides an ideal porous support and allows both high Faradaic and high capacitive currents to be achieved. The capacitive current obtained after immobilisation of 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide and immersion into aqueous electrolyte indicates that most (ca 65%) of the real carbon nanofiber surface is active, electrically connected to the substrate electrode, and in direct contact with the ionic liquid. The reversible oxidation and re-reduction of t-butylferrocene in 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide occurs at a potential which depends on the composition and nature of the aqueous electrolyte as well as on the type of electrode. The position of differential pulse voltammetric oxidation peak potentials is shown to depend on the type of anion present in the aqueous solution phase with most significant effects for the hydrophobic and anions. Although only the Faradaic voltammetric response allows the ion transfer mechanism to be analysed, anion transfer is proposed to be coupled to both Faradaic and capacitive charge transfer. [Copyright &y& Elsevier]

Abstract: The electrode based on silicate carbon composite material was modified with redox probe (t-butylferrocene) solution in ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate or 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide). After immersion into an aqueous solution it was studied by cyclic voltammetry. It exhibits electrochemical signal connected with electrode reaction of the redox probe dissolved in ionic liquid. The heterogeneous structure of electrode material enhances substantially efficiency of the electrode process in comparison to the drop deposited on flat electrode surface. The midpeak potential depends on the hydrophobicity of the anion present in the aqueous solution indicating significant contribution of anion injection into the ionic liquid following the electron transfer. The efficiency of the electrode process is much larger than that of similar electrode modified with the redox probe solution in less viscous organic polar solvent. [Copyright &y& Elsevier]

Abstract: Nanoporous silicate submicrometre particles covered with imidazolium cationic groups were obtained by sol–gel processing of the ionic liquid 1-methyl-3-(3-trimethoxysilylpropyl)imidazolium bis(trifluoromethylsulfonyl)imide together with tetramethoxysilane. They were immobilised on indium tin oxide electrode by dropping them in a suspension on the electrode surface followed by solvent evaporation. The particles modified electrode acts as a sponge for anions dissolved in aqueous solution. [Copyright &y& Elsevier]

In this letter the authors experimentally demonstrate the strong coupling regime at room temperature between a surface plasmon and an exciton from an auto-organized quantum well. The sample is formed by a two dimensional layered perovskite-type semiconductor: s(C6H5C2H4–NH3)PbI4, spin coated onto a silver film. The dispersion lines resulting from reflectometry experiments performed at room temperature in the Kretschmann geometry present an anticrossing with a Rabi splitting of 167 meV. The emission of the low energy polariton is presented. [ABSTRACT FROM AUTHOR]

Background: For the first time, we present regional-level cancer incidence and world-standardized mortality rates for cancers for Martinique, Guadeloupe and French Guiana.Methods: For Martinique, Guadeloupe and French Guiana, incidence data come from population-based cancer registries, and cover the periods 2007-2014, 2008-2014 and 2010-2014 respectively. Standardized incidence and mortality rates were calculated using the world population.Results: In the 3 regions, all cancers combined represent 3567 new cases per year, of which 39.8% occur in women, and 1517 deaths per year (43.4% in women). Guadeloupe and Martinique present similar world-standardized incidence rates. Among gynaecological cancers, breast cancer, the second most common cancer type in the 3 regions, has an incidence rate 35 to 46% lower than in mainland France. On the other hand, cervical cancer has a higher incidence rate, particularly in French Guiana. For both endometrial cancer and ovarian cancer, no significant differences in incidence rates are found compared to mainland France. Regarding mortality, world-standardized mortality rates are similar between Guadeloupe and Martinique, and higher than in French Guiana. This situation compares favourably with mainland France (all cancers). Among gynaecological cancers, the mortality rate is lower for breast cancer in all regions compared to mainland France, and also lower for ovarian cancer in Martinique and Guadeloupe, but higher (albeit non-significantly) in French Guiana.Conclusion: The ethno-geographic and socio-demographic characteristics in this population of mainly Afro-Caribbean origin could partially explain these disparities. Major disparities exist for certain cancer sites: excess incidence and excess mortality for cervical cancer; lower, but increasing incidence of breast cancer. [ABSTRACT FROM AUTHOR]

The fabrication of microcavities by a sol–gel process and their optical properties are described. The cavities are constituted of an Eu[sup 3+]-doped SiO[sub 2] active layer inserted between two Bragg mirrors, fabricated by stacking alternatiely undoped TiO[sub 2] and SiO[sub 2] sol–gel thin films. Eu[sup 3+] luminescence modification due to the cavity effect, intensity enhancement and modification of the line shape has been observed, and shows a cavity quality factor of 1200. The reflectivity factor of the associated Bragg mirrors reaches 99.8% for seven alternate SiO[sub 2]/TiO[sub 2] layers. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this article, the Raman signal of CdSe nanocrystals well dispersed in a very thin SiO[sub 2] film (20 nm) has been investigated by surface plasmon excitation in a resonant Raman spectroscopy experiment. In order to perform the excitation, the thin SiO[sub 2] layer containing nanocrystals is deposited on a well-defined silver layer. The surface plasmon excitation increases the sensitivity of the Raman experiment, compared to the conventional setup, and allows the observation of a small number of nanocrystals (around 5000). The luminescence has also been measured and its dependence with the separation between the metal layer and CdSe nanocrystals is analyzed. In particular the quenching of the luminescence for thin film has been used to obtain only the Raman signal in resonant configuration. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present experimental results of a Kretschmann-prism coupler method used in Raman scattering experiments with ultrathin (few nanometers) TiO[sub 2] sol-gel films deposited on a metallic silver layer characterized by surface plasmon resonance (SPR) experiments. In this article, we describe a new optical device as an application of SPR properties and coupled with a micro-Raman scattering setup. The enhancement factor (150) of the Raman intensity in comparison to the classical way allows us to determine the critical thin films structure. Optical results are then discussed and compared to transmission electron microscopy. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Many biotic and abiotic parameters affect the metabolites involved in the organoleptic and health value of fruits. It is therefore important to understand how the growers' decisions for cultivar and orchard management can affect the fruit composition. Practices, cultivars and/or year all might participate to determine fruit composition. To hierarchize these factors, fruit weight, dry matter, soluble solids contents, titratable acidity, individual sugars and organics acids, and phenolics were measured in three apple cultivars (‘Ariane’, ‘Melrose’ and ‘Smoothee’) managed under organic, low-input and conventional management. Apples were harvested at commercial maturity in the orchards of the cropping system experiment BioREco at INRA Gotheron (Drôme, 26) over the course of three years (2011, 2012 and 2013). The main factors affecting primary and secondary metabolites, in both apple skin and flesh, were by far the cultivar and the yearly conditions, while the management system had a very limited effect. When considering the three cultivars and the year 2011 to investigate the effect of the management system per se, only few compounds differed significantly between the three systems and in particular the total phenolic content did not differ significantly between systems. Finally, when considering orchards grown in the same pedoclimatic conditions and of the same age, instead of the usual organic vs. conventional comparison, the effect of the management system on the apple fruit quality (Fruit weight, dry matter, soluble solids content, titratable acidity, individual sugars, organic acids, and phenolics) was very limited to non-significant. The main factors of variation were the cultivar and the year of cropping rather than the cropping system. More generally, as each management system (e.g. conventional, organic…) encompasses a great variability of practices, this highlights the importance of accurately documenting orchard practices and design beside the generic type of management in such studies. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the synthesis of tin nanoparticles (NPs) or tin/carbon composites, in room temperature ionic liquids (RTILs), that could be used as structured anode materials for Li-ion batteries. An innovative route for the synthesis of Sn nanoparticles in such media is successfully developed. Compositions, structures, sizes and morphologies of NPs were characterized by high-energy X-ray diffraction (HEXRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). Our findings indicated that (i) metallic tetragonal ß-Sn was obtained and (ii) the particle size could be tailored by tuning the nature of the RTILs, leading to nano-sized spherical particles with a diameter ranging from 3 to 10 nm depending on synthesis conditions. In order to investigate carbon composite materials for Li-ion batteries, Sn nanoparticles were successfully deposited on the surface of multi-wall carbon nanotubes (MWCNT). Moreover, electrochemical properties have been studied in relation to a structural study of the nanocomposites. The poor electrochemical performances as a negative electrode in Li-ion batteries is due to a significant amount of RTIL trapped within the pores of the nanotubes as revealed by XPS investigations. This dramatically affected the gravimetric capacity of the composites and limited the diffusion of lithium. The findings of this work however offer valuable insights into the exciting possibilities for synthesis of novel nano-sized particles and/or alloys (e.g. Sn-Cu, Sn-Co, Sn-Ni, etc.) and the importance of carbon morphology in metal pulverization during the alloying/ dealloying process as well as prevention of ionic liquid trapping. [ABSTRACT FROM AUTHOR]

In this paper we describe the modifications in the GaAs quantum well (QW) optical properties induced by the proximity of a metallic film. The formation of hybrid plasmon/exciton states composed of a mix of heavy-hole exciton/light-hole exciton mixed states is demonstrated with reflectometry experiments. Alternative surface modes, namely Tamm plasmons, can also induce hybridization with the QW excitons with Rabi splitting energy of 11.5 meV. Plasmonic Tamm states are interface modes formed at the boundary between a photonic structure and a metallic layer. These modes present both the advantages of surface plasmons and of microcavities photonic modes. A conventional lasing effect will also be described in Tamm plasmon structure containing QWs. Tamm plasmons can be spatially confined by structuring the metallic part of the system, thus reducing the size of the mode and allowing various geometries. Due to the relatively low damping and the versatility of the Tamm geometries, these modes are good candidates for a new type of lasers. [ABSTRACT FROM AUTHOR]

Abstract: The effect of linker of three-dimensional, hydrophilic-carbon-nanoparticle film-electrodes prepared by layer-by-layer method on redox probe accumulation and bioelectrocatalytic dioxygen reduction was studied and compared for two different electrode scaffolds. The linker in both of these scaffolds was based on the same ionic liquid sol–gel precursor, 1-methyl-3-(3-trimethoxysilylpropyl) imidazolium bis(trifluoromethyl-sulfonyl)imide. The first electrode type was prepared by alternative immersion of tin doped indium oxide substrate in an aqueous suspension of carbon nanoparticles modified with phenyl sulphonic groups and a sol composed of ionic liquid sol–gel precursor and tetramethoxysilane. For the second electrode type sol was replaced by a methanolic suspension of silicate submicroparticles with appended imidazolium functional groups. In both films 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) anions accumulate irreversibly. In the case of the first electrode electrostatic attraction plays the more important role in comparison to the case of the second where stable adsorption of the redox probe takes place. After adsorption of bilirubin oxidase, electrodes obtained from sol and carbon nanoparticles exhibit modest bioelectrocatalytic activity towards dioxygen reduction at pH 4.8, however those obtained from oppositely charged particles are much more efficient. The magnitude of the associated catalytic current in both cases depends on the number of immersion and withdrawal steps. Interestingly, mediatorless catalysis at electrodes obtained from oppositely charged particles is more efficient than mediated catalysis. [Copyright &y& Elsevier]

Quantifying the impacts of inbreeding and genetic drift on fitness traits in fragmented populations is becoming a major goal in conservation biology. Such impacts occur at different levels and involve different sets of loci. Genetic drift randomly fixes slightly deleterious alleles leading to different fixation load among populations. By contrast, inbreeding depression arises from highly deleterious alleles in segregation within a population and creates variation among individuals. A popular approach is to measure correlations between molecular variation and phenotypic performances. This approach has been mainly used at the individual level to detect inbreeding depression within populations and sometimes at the population level but without consideration about the genetic processes measured. For the first time, we used in this study a molecular approach considering both the interpopulation and intrapopulation level to discriminate the relative importance of inbreeding depression vs. fixation load in isolated and non-fragmented populations of European tree frog ( Hyla arborea), complemented with interpopulational crosses. We demonstrated that the positive correlations observed between genetic heterozygosity and larval performances on merged data were mainly caused by co-variations in genetic diversity and fixation load among populations rather than by inbreeding depression and segregating deleterious alleles within populations. Such a method is highly relevant in a conservation perspective because, depending on how populations lose fitness (inbreeding vs. fixation load), specific management actions may be designed to improve the persistence of populations. [ABSTRACT FROM AUTHOR]

Abstract: We report on the strong coupling between a Tamm plasmon mode and excitons from inorganic quantum wells. The sample is formed by an AlAs/GaAlAs Bragg reflector containing InGaAs QWs in its high refractive index layers, on top of which a thin silver film is deposited. Angle resolved reflectometry experiments at low temperature (77 K) show a clear anticrossing in the dispersion relations, evidencing the strong coupling regime. The Rabi splitting amounts to 11.5 meV. Emission from low and high energy Tamm plasmon/exciton polaritons is also demonstrated. Experimental data are in very good agreement with transfer matrix simulations. [Copyright &y& Elsevier]

Connectivity among populations plays a crucial role in maintaining genetic variation at a local scale, especially in small populations affected strongly by genetic drift. The negative consequences of population disconnection on allelic richness and gene diversity (heterozygosity) are well recognized and empirically established. It is not well recognized, however, that a sudden drop in local effective population size induced by such disconnection produces a temporary disequilibrium in allelic frequency distributions that is akin to the genetic signature of a demographic bottleneck. To document this effect, we used individual-based simulations and empirical data on allelic richness and gene diversity in six pairs of isolated versus well-connected (core) populations of European tree frogs. In our simulations, population disconnection depressed allelic richness more than heterozygosity and thus resulted in a temporary excess in gene diversity relative to mutation drift equilibrium (i.e., signature of a genetic bottleneck). We observed a similar excess in gene diversity in isolated populations of tree frogs. Our results show that population disconnection can create a genetic bottleneck in the absence of demographic collapse. [ABSTRACT FROM AUTHOR]

Although nocturnal anurans use vision for reproductive communication, it remains unknown whether they see colours at night. Here, we explored this question in the European treefrog (Hyla arborea), by conducting two mate choice experiments under controlled light conditions. Experiments involved static male models with identical calls but different vocal sac colouration combining chromatic (red/orange) and brightness (dark/light) information. We found that females preferred dark red over light orange, evidencing for the first time a visually-guided mate choice in nocturnal diffuse light conditions. Conversely, females did not discriminate between dark orange and light red. The preference for dark over light in the first but not in the second experiment suggested that females had not only access to brightness cues but also to chromatic cues. The absence of preference may originate from females choosing at random in a situation where colour and brightness cues may convey contradictory information about male quality or from individual heterogeneity in the type of cues used for mate choice. Overall, these experiments provide the first support for the use of colour vision in a nocturnal amphibian. [ABSTRACT FROM AUTHOR]

Abstract: We report the fabrication of a carbon nanotube silica composite. This inorganic composite is produced with the sol–gel technique and deposited in thin films by the dip-coating method. The functionalization of multiwall carbon nanotubes is a decisive step in order to introduce them inside a silica matrix. Functionalization ensures good homogeneity of multiwall carbon nanotubes. Atomic force microscopy and surface enhanced Raman spectroscopy demonstrate the well dispersion at the nanometer scale and a micrometer scale, respectively. Moreover, AFM measurements show carbon nanotubes are present in individualized form. [Copyright &y& Elsevier]

A new clay-based nanocomposite has been developed for non-linear optical waveguiding applications. Thin layers are deposited on glass substrates by using dip coating technique from an aqueous solution made of a Laponite suspension mixed with a lithium iodate (LiIO 3 ) aqueous solution. Transparent layers with waveguiding properties are obtained with an effective non-linear coefficient of about 1.4 pm/V for a 55% vol. LiIO 3 composite. Control of nanocrystals orientation has been performed by applying an electric field with Corona discharge or deposited gold electrodes. Characterisation of nanocrystals orientation was done by Second Harmonic Generation (SHG) measurements and polarised light optical microscopy. [ABSTRACT FROM AUTHOR]

The fabrication and the study of sol gel-microcavities strongly doped with CdSe nanocrystals are presented. The Fabry-Perot microcavities are formed by a Distributed Bragg Reflector covered with a CdSe doped active layer and a silver mirror. These microcavities are studied with reflectometry experiments. We observe that the cavity resonance peak is enlarged by a factor two when his spectral position corresponds to the first absorption line of the CdSe nanocrystals. Transfer matrix method calculation taking into account the CdSe absorption have been performed and are in good agreement with the experimental values. [ABSTRACT FROM AUTHOR]

The present paper presents our work consisting of `doping'' SiO2 sol–gel matrices with 5–30% mass of LiIO3 nanocrystals. Indeed, bulk α-LiIO3 is known to be very efficient for second harmonic generation (SHG). Bulk nanocomposite samples have been first studied showing nanocrystallites with size ranging from 50 to 400 nm and SHG. Then dip and spin coating methods have been used to build thin layers. Being given that LiIO3 crystals present structurally a strong dipolar moment, non-linear optical (NLO) properties may be enhanced using Corona discharges to orientate nanocrystals. This paper relates the fabrication process and the structural and optical characterizations of bulk and thin layer material. [Copyright &y& Elsevier]

We describe the first elaboration of carbon nanotube tips (CN-tips) by the sol–gel technique. The CN-tips consist of single carbon nanotubes (CNs) or bundles sheathed by a nanometric layer of TiO2 fixed to the apex of a W base tip and oriented along its major axis. The straight-forward method potentially permits low cost batch fabrication. Structural analysis has been realized by transmission electron microscopy (TEM). These CN-tips are interesting for applications in applied surface science such as field emission (FE) sources and near field microscopy probes. A first field emission study has also been carried out showing that the TiO2 layer does not block FE. Relatively stable emission at voltages usual to FE from CNs at up to 0.8 μA current were obtained. [Copyright &y& Elsevier]

We report here the successful inclusion of carbon nanotubes (CNs) into a TiO2 matrix prepared by a sol–gel method. The presence of CNs in the sol–gel matrix and the structure of the film were analyzed principally by transmission electron microscopy. Complementary information about the behavior of embedded carbon nanotubes versus heat treatment and ion irradiation were obtained by X-ray photoelectron spectroscopy. The elaboration of an inorganic matrix containing embedded carbon nanotubes leads to a new nanocomposite. The possible applications of this nanocomposite are discussed. [Copyright &y& Elsevier]

We discuss attractive potentialities of the sol–gel process applied to planar microcavities with distributed Bragg reflectors (DBRs). This method is well known for its good flexibility and the optical quality of the thin films obtained. The DBRs are composed of alternated TiO2 and SiO2 thin films. One of the main problems of the sol–gel process is the stresses induced during the layers heat treatment leading to defects and cracks in the films. The study of these stresses shows that with the appropriate annealing temperature and duration of the firing process, the stress in the SiO2 layers partially compensates the stress in the TiO2 layers. DBRs and microcavities formed by 60 stacked layers have been elaborated in these conditions. The reflectivity of such sol–gel DBRs reaches 99.7%. The sol–gel DBRs are used to fabricate microcavities containing Eu3+ rare earth ions with a quality factor of approximately 1000. [Copyright &y& Elsevier]

We report on the observation of the strong coupling regime occurring between a Tamm plasmon (TP) mode and an exciton from inorganic quantum wells (QWs). The sample is formed by a silver thin film deposited onto an AlAs/GaAlAs Bragg reflector containing InGaAs QWs located in the high refractive index layers. Angular resolved reflectometry experiments evidence a clear anticrossing in the dispersion relations, a signature of the strong coupling regime. The Rabi splitting energy is 11.5 meV. The experimental data are in very good agreement with simple transfer matrix calculations. The emission from low and high energy TP/exciton polaritons is also demonstrated. [ABSTRACT FROM AUTHOR]

In this letter the authors demonstrate that the emission of plasmon/exciton polaritons in an organic semiconductor can be extracted using surface plasmon cross coupling. A J-aggregated cyanine dye layer is deposited on a silver film and then the whole structure is periodically corrugated. As a result of this corrugation, the dispersion lines of the surface modes on both sides of the silver layer may cross. At this crossing point, an increase in the polaritonic emission is observed. The contributions of unpolarized incoherent states and of the TM polarized polaritons emission are separated. [ABSTRACT FROM AUTHOR]

A Laponite clay-based lithium iodate nanocomposite have been synthesized for nonlinear optical applications. After addition of lithium iodate aqueous solution to a colloidal suspension of Laponite JS, thin layers are elaborated from this sol using dip-coating technique. After drying and heat treatments between 150 and 220°C, LiIO3 crystallizes in the matrix with nanometer size. As a result of their strong dipolar moment, the LiIO3 crystals can be orientated under an external electric field during nucleation. Planar waveguides have been elaborated on glass substrates and studied using m-lines spectroscopy. The experimental nonlinear optical response has been compared to predictions of a model and an effective nonlinear coefficient deff=1.4 pm/V has been measured. [ABSTRACT FROM AUTHOR]

We describe the patterning of optically active material using the micro-contact printing technique. The optical active layer is an organized J-aggregated cyanine dye film, deposited onto a patterned PDMS stamp using a layer-by-layer technique, based on an alternate adsorption of oppositely charged species. The resulting polyelectrolyte multilayers (PEMs) are transferred by micro-contact printing onto bare Pyrex or silver-coated Pyrex substrates. AFM, SEM and optical images are presented, showing that the micrometer scale pattern is well transferred onto the substrate. The absorption spectra of the transferred active layer indicate that the particular optical properties of the transferred aggregated dye, which are crucial for polariton diodes or plasmonic devices, are not modified by the process. This work shows that micro-contact printing used in combination with the layer-by-layer deposition of PEMs (allowing molecular scale control of the layer thickness) has a specific potential for the fabrication of devices involving optical organic materials. [ABSTRACT FROM AUTHOR]