A new Coniopterygidae from Lebanese amber

We describe the oldest fossil Coniopterygidae, possibly attributable to the Coniopteryginae, in the new genus and species Libanosemidalis hammanaensis, from the outcrop Hammana / Mdeyrij in the Lower Cretaceous amber of Lebanon. This fossil shares with the extant and Cenozoic lineages of Coniopterygidae the presence of only two M branches, unlike other Cretaceous representatives of the family

A new Coniopterygidae from Lebanese amber

We describe the oldest fossil Coniopterygidae, possibly attributable to the Coniopteryginae, in the new genus and species Libanosemidalis hammanaensis, from the outcrop Hammana / Mdeyrij in the Lower Cretaceous amber of Lebanon. This fossil shares with the extant and Cenozoic lineages of Coniopterygidae the presence of only two M branches, unlike other Cretaceous representatives of the family.We describe the oldest fossil Coniopterygidae, possibly attributable to the Coniopteryginae, in the new genus and species Libanosemidalis hammanaensis, from the outcrop Hammana / Mdeyrij in the Lower Cretaceous amber of Lebanon. This fossil shares with the extant and Cenozoic lineages of Coniopterygidae the presence of only two M branches, unlike other Cretaceous representatives of the family

Utilisation of the sol-gel technique for the development of novel stationary phases for capillary electrochromatography on a chip

Capillary electrochromatography (CEC) appears ideally suited for high performance separations at small scale, i.e. on a chip. Problems with the reproducible production of the required HPLC column, but also the lack of commercially available CEC instruments have prevented many putative applicants of this promising technique from entering the field. In this paper, a fast and easy way to produce self-containing open-tubular CEC columns (C8-moieties for reversed phase applications) by the sol-gel technique is described. The corresponding chips were designed to be compatible with a commercial system for capillary electrophoresis (namely a Beckman P/ACE 5500 system with diode array detection). Method development and application hence benefited from the injection and the detection options of this setup. The separation of a mixture of three uncharged analytes (polycyclic aromatic hydrocarbons) by the chip is given as example. Under optimized conditions, the performance of the chip appeared to be comparable or better than that of capillary-based CEC columns of the same kind

Powder blasting for the realisation of microchips for bio-analytic applications

We introduce powder blasting for the fabrication of glass microchips. Powder blasting is a fast and cheap technique with which we pattern channels in sodalime and pyrex glass with a width down to 100µm. We combine the technique with appropriate bonding procedures to realise sealed microchannel structures. We study the transport of fluorescent dye solutions and fluorescent beads within channels made by powder blasting and in "classical" channels made by HF-etching. We find a remarkable difference in sign of the electric field induced flow for both types of channels and explain the observed strong plug broadening effects in the powder blasted channels

Measuring a population of spin waves from the electrical noise of an inductively coupled antenna

We study how a population of spin waves can be characterized from the analysis of the electrical microwave noise delivered by an inductive antenna placed in its vicinity. The measurements are conducted on a synthetic antiferromagnetic thin stripe covered by a micron-sized antenna that feeds a spectrum analyser after amplification. The antenna noise contains two contributions. The population of incoherent spin waves generates a fluctuating field that is sensed by the antenna: this is the "magnon noise". The antenna noise also contains the contribution of the electronic fluctuations: the Johnson-Nyquist noise. The latter depends on all impedances within the measurement circuit; this includes the antenna self-inductance. As a result, the electronic noise contains information about the magnetic susceptibility, though it does not inform on the absolute amplitude of the magnetic fluctuations. For micrometer-sized systems at thermal equilibrium, the electronic noise dominates and the pure magnon noise cannot be determined. If in contrast the spinwave bath is not at thermal equilibrium with the measurement circuit, and if the spinwave population can be changed then one could measure a mode-resolved effective magnon temperature provided specific precautions are implemented

The genome of Apis mellifera: dialog between linkage mapping and sequence assembly

Two independent genome projects for the honey bee, a microsatellite linkage map and a genome sequence assembly, have interactively produced an almost complete organization of the euchromatic genome

Thickness dependence of the interfacial Dzyaloshinskii-Moriya interaction in inversion symmetry broken systems

In magnetic multilayer systems, a large spin-orbit coupling at the interface between heavy metals and ferromagnets can lead to intriguing phenomena such as the perpendicular magnetic anisotropy, the spin Hall effect, the Rashba effect, and especially the interfacial Dzyaloshinskii-Moriya (IDM) interaction. This interfacial nature of IDM interaction has been recently revisited because of its scientific and technological potential. Here, we demonstrate an experimental technique to straightforwardly observe the IDM interaction, namely Brillouin light scattering. The non-reciprocal spin wave dispersions, systematically measured by Brillouin light scattering, allow not only the determination of the IDM energy densities beyond the regime of perpendicular magnetization but also the revelation of the inverse proportionality with the thickness of the magnetic layer, which is a clear signature of the interfacial nature. All together, our experimental and theoretical approaches involving double time Green,s function methods open up possibilities for exploring magnetic hybrid structures for engineering the IDM interaction

Fine Scale Analysis of Crossover and Non-Crossover and Detection of Recombination Sequence Motifs in the Honeybee (Apis mellifera)

BACKGROUND: Meiotic exchanges are non-uniformly distributed across the genome of most studied organisms. This uneven distribution suggests that recombination is initiated by specific signals and/or regulations. Some of these signals were recently identified in humans and mice. However, it is unclear whether or not sequence signals are also involved in chromosomal recombination of insects. METHODOLOGY: We analyzed recombination frequencies in the honeybee, in which genome sequencing provided a large amount of SNPs spread over the entire set of chromosomes. As the genome sequences were obtained from a pool of haploid males, which were the progeny of a single queen, an oocyte method (study of recombination on haploid males that develop from unfertilized eggs and hence are the direct reflect of female gametes haplotypes) was developed to detect recombined pairs of SNP sites. Sequences were further compared between recombinant and non-recombinant fragments to detect recombination-specific motifs. CONCLUSIONS: Recombination events between adjacent SNP sites were detected at an average distance of 92 bp and revealed the existence of high rates of recombination events. This study also shows the presence of conversion without crossover (i. e. non-crossover) events, the number of which largely outnumbers that of crossover events. Furthermore the comparison of sequences that have undergone recombination with sequences that have not, led to the discovery of sequence motifs (CGCA, GCCGC, CCGCA), which may correspond to recombination signals

Representativeness of microsatellite distributions in genomes, as revealed by 454 GS-FLX Titanium pyrosequencing

<p>Abstract</p> <p>Background</p> <p>Microsatellites are markers of choice in population genetics and genomics, as they provide useful insight into patterns and processes as diverse as genome evolutionary dynamics and demographic processes. The acquisition of microsatellites through multiplex-enriched libraries and 454 GS-FLX Titanium pyrosequencing is a promising new tool for the isolation of new markers in unknown genomes. This approach can also be used to evaluate the extent to which microsatellite-enriched libraries are representative of the genome from which they were isolated. In this study, we deciphered potential discrepancies in microsatellite content recovery for two reference genomes (<it>Apis mellifera </it>and <it>Danio rerio</it>), selected on the basis of their extreme heterogeneity in terms of the proportions and distributions of microsatellites on chromosomes.</p> <p>Results</p> <p>The <it>A. mellifera </it>genome, in particular, was found to be highly heterogeneous, due to extremely high rates of recombination, with hotspots, but the only bias consistently introduced into pyrosequenced multiplex-enriched libraries concerned sequence length, with the overrepresentation of sequences 160 to 320 bp in length. Other deviations from expected proportions or distributions of motifs on chromosomes were observed, but the significance and intensity of these deviations was mostly limited. Furthermore, no consistent adverse competition between multiplexed probes was observed during the motif enrichment phase.</p> <p>Conclusions</p> <p>This approach therefore appears to be a promising strategy for improving the development of microsatellites, as it introduces no major bias in terms of the proportions and distribution of microsatellites.</p