Detection of genetically modified plant products by protein strip testing: an evaluation of real-life samples

The determination of the presence of genetically modified plant material by the detection of expressed genetically engineered proteins using lateral flow protein strip tests has been evaluated in different matrices. The presence of five major genetically engineered proteins (CP4-EPSPS, CryIAb, Cry9C, PAT/pat and PAT/bar protein) was detected at low levels in seeds, seed/leaf powder and leaf tissue from genetically modified soy, maize or oilseed rape. A comparison between “protein strip test” (PST) and “polymerase chain reaction” (PCR) analysis of genetically modified food/feed samples demonstrates complementarities of both techniques.     

Evidence for metal-semiconductor transitions in twisted and collapsed double-walled carbon nanotubes by scanning tunneling microscopy

The atomic and electronic structure of a twisted and collapsed double-walled carbon nanotube was characterized using scanning tunneling microscopy and spectroscopy. It was found that the deformation opens an electronic band gap in an otherwise metallic nanotube, which has major ramifications on the use of carbon nanotubes for electronic applications. Fundamentally, the importance of the intershell interaction in this double-walled carbon nanotube points to the potential of a reversible metal-semiconductor junction, which can have device applications, as well as a caution in the design of semiconductor components based on carbon nanotubes. Lattice registry effects between the two neighboring walls evidenced by atomically resolved images confirm earlier first principle calculations indicating that the helicity influences the collapsed structure and show excellent agreement with the predicted twisted-collapse mode.     

New Mononuclear Cu(II) Complexes and 1D Chains with 4-Amino-4H-1,2,4-triazole

The crystal structures of two mononuclear Cu(II) NH₂trz complexes [Cu(NH₂trz)₄(H₂O)](AsF₆)₂ (I) and [Cu(NH₂trz)₄(H₂O)](PF₆)₂ (II) as well as two coordination polymers [Cu(μ₂-NH₂trz)₂Cl]Cl·H₂O (III) and [Cu(μ₂-NH₂trz)₂Cl] (SiF₆)_0.5·1.5H₂O (IV) are presented. Cationic 1D chains with bridging bis-monodentate μ₂-coordinated NH₂trz and bridging μ₂-coordinated chloride ligands are present in III and IV. In these coordination polymers, the Cu(II) ions are strongly antiferromagnetically coupled with J = −128.4 cm⁻¹ for III and J = −143 cm⁻¹ for IV (H = −J∑S_iS_i+1), due to the nature of the bridges between spin centers. Inter-chain interactions present in the crystal structures were taken into consideration, as well as g factors, which were determined experimentally, for the quantitative modeling of their magnetic properties.     

Multielementary (Cd, Cu, Pb, Zn, Ni) Stable Isotopic Exchange Kinetic (SIEK) method to characterize polymetallic contaminations

A new method is proposed to precisely and simultaneously quantify the exchangeable pool of metals in soils and to describe its reactivity at short- and long-term. It is based on multielementary Stable Isotopic Exchange Kinetics (multi-SIEK), first validated by a comparison between two monoelementary radioactive ((109)Cd*, (65)Zn*) IEK experiments, a mono- ((106)Cd) and multi- ((62)Ni, (65)Cu, (67)Zn, (106)Cd, (204)Pb) SIEK. These experiments were performed on a polluted soil located near the Zn smelter plant of Viviez (Lot watershed, France). The IEK results obtained for Cd and Zn were consistent across the experiments. (109)Cd*, (65)Zn* IEK, and multi-SIEK were then applied on 3 non- and moderate impacted soils that also provided consistent results for Cd and Zn. Within these experimental conditions, it can be concluded that no competition occurs between Cd, Zn, and the other metals during SIEK. Multi-SIEK results indicate that the isotopically exchangeable pool of Ni, Zn, and Cu are small (E(Ni), E(Zn), and E(Cu) values up to 17%) whatever the pollution degree of the soils considered in this study and whatever the duration of the interaction. On the contrary, Cd displays the highest E values (from 35% to 61% after 1 week), and E(Pb) displays a maximum value of 26% after 1 week. The multi-SIEK provides useful information on metal sources and reactivity relationship. Ni would be located in stable pedogenic phases according to its very low enrichment factor. The low E(Zn) and E(Cu) are consistent with location of Zn and Cu in stable phases coming from tailings erosion. Though Pb enrichments in soils may also be attributed to tailings particles, its larger exchangeable pool suggests that the Pb-bearing phases are more labile than those containing Zn and Cu. The high mobility of Cd in upstream soils indicates that it has been mostly emitted as reactive atmospheric particles during high temperature ore-treatment.     

Luminescence nanothermometry with alkyl-capped silicon nanoparticles dispersed in nonpolar liquids

Silicon nanoparticles (Si NPs) with a diameter size ranging from 4 to 8 nm were successfully fabricated. They exhibit a visible photoluminescence (PL) due to the quantum confinement effect. Chemical functionalization of these Si NPs with alkyl groups allowed to homogeneously disperse them in nonpolar liquids (NPLs). In comparison to most of literature results for Si NPs, an important PL peak position variation with temperature (almost 1 meV/K) was obtained from 303 to 390 K. The influence of the liquid viscosity on the peak positions is also presented. These variations are discussed considering energy transfer between nanoparticles. The high PL thermal sensitivity of the alkyl-capped Si NPs paves the way for their future application as nanothermometers.     

Speech enhancement based on hybrid algorithm

A hybrid algorithm that incorporates the minimum mean square error (MMSE) algorithm and the auditory masking algorithm for speech enhancement is proposed. The proposed algorithm results in a significant reduction in residual noise compared with that in the enhanced speech produced by the MMSE algorithm alone     

Reactivity of M/TiN/SiC systems (M?=?W and Mo) at high temperature

Owing to the development of high temperature applications using SiC, this study examines the effect of TiN coatings against Si and C atoms diffusion in presence of two refractory metals (W or Mo). Indeed, SiC reacts rapidly with these metals at elevated temperatures generating unacceptable reaction zones and a mechanical embrittlement. Samples used during this work were prepared on wire and planar metallic substrates, SiC and TiN being deposited by CVD. The effect given by TiN interlayers with thicknesses between 10 and 20 μm was considered at 1773 K. From our results, TiN can be considered as an effective diffusion barrier in presence of W, whereas it ensures no real protection in the case of Mo-containing samples.     

Dynamic superimposition of synthetic objects on rigid and simple-deformable real objects

A current challenge in augmented reality applications is the accurate superimposition of synthetic objects on real objects within the environment. This challenge is heightened when the real objects are in motion and/or are non-rigid. In this article, we present a robust method for real-time, optical superimposition of synthetic objects on dynamic, rigid and simple-deformable real objects. Moreover, we illustrate this general method with the VRDA Tool, a medical education application enabling the visualization of internal human knee joint anatomy on a real human knee.     

Detection of a polymorphic Mesoamerican symbol using a rule-based approach

This paper describes a technique to recognize a Mesoamerican symbol whose shape is extremely variable. We extract symbols from a drawing and we encode them as discrete curves. We perform the recognition using a set of rules that define the correct symbol. One of the rules is the presence of a single symmetry axis. We describe a comparison metric between curves in order to search for symmetries. The other rules used for the recognition concern the morphology of the symbol. The proposed technique proves to be fast and efficient. We present recognition results obtained on various pre-hispanic images. The rule-based approach proposed and implemented here, appears suitable to detect polymorphic signs, a common feature of Mesoamerican symbols. To the best of our knowledge, this is the first study of pattern recognition into the field of Mesoamerican iconography.