A high resolution electron energy loss spectroscopy study of the Fermi resonance of CO₂ adsorbed on a Ag(110)/CO₃ layer

The adsorption of CO2 on a Ag(110) surface precovered with a saturated CO3 layer has been studied by high resolution electron energy loss spectroscopy (HREELS). A weakly bound state of CO2 is stabilized by the presence of carbonate. In addition to the losses of the bend (658 cm−1) and the antisymmetric stretch (2343 cm−1) fundamental modes, the presence of two peaks in the frequency region of the symmetric stretch mode have been observed. Such a loss pair is characteristic for the existence of a Fermi resonance, between the overtone of the bend and the symmetric stretch vibration, which had been studied in detail for the gas phase CO2 molecule. By use of three CO2 isotopomers the existence of the Fermi resonance in the adsorbed state has been verified and the Fermi constant and the energy of the unperturbed vibrations have been determined from the isotopic shifts. The character of the CO2 molecule is almost unaffected by the bonding and it adsorbs in a tilted geometry

Compiling Linguistic Constraints into Finite State Automata

International audienceThis paper deals with linguistic constraints encoded in the form of (binary) tables, generally called lexicon-grammar tables. We describe a unified method to compile sets of tables of linguistic constraints into Finite State Automata. This method has been practically implemented in the linguistic platform Unitex

New first trimester crown-rump length's equations optimized by structured data collection from a French general population

--- Objectives --- Prior to foetal karyotyping, the likelihood of Down's syndrome is often determined combining maternal age, serum free beta-HCG, PAPP-A levels and embryonic measurements of crown-rump length and nuchal translucency for gestational ages between 11 and 13 weeks. It appeared important to get a precise knowledge of these scan parameters' normal values during the first trimester. This paper focused on crown-rump length. --- METHODS --- 402 pregnancies from in-vitro fertilization allowing a precise estimation of foetal ages (FA) were used to determine the best model that describes crown-rump length (CRL) as a function of FA. Scan measures by a single operator from 3846 spontaneous pregnancies representative of the general population from Northern France were used to build a mathematical model linking FA and CRL in a context as close as possible to normal scan screening used in Down's syndrome likelihood determination. We modeled both CRL as a function of FA and FA as a function of CRL. For this, we used a clear methodology and performed regressions with heteroskedastic corrections and robust regressions. The results were compared by cross-validation to retain the equations with the best predictive power. We also studied the errors between observed and predicted values. --- Results --- Data from 513 spontaneous pregnancies allowed to model CRL as a function of age of foetal age. The best model was a polynomial of degree 2. Datation with our equation that models spontaneous pregnancies from a general population was in quite agreement with objective datations obtained from 402 IVF pregnancies and thus support the validity of our model. The most precise measure of CRL was when the SD was minimal (1.83mm), for a CRL of 23.6 mm where our model predicted a 49.4 days of foetal age. Our study allowed to model the SD from 30 to 90 days of foetal age and offers the opportunity of using Zscores in the future to detect growth abnormalities. --- Conclusion --- With powerful statistical tools we report a good modeling of the first trimester embryonic growth in the general population allowing a better knowledge of the date of fertilization useful in the ultrasound screening of Down's syndrome. The optimal period to measure CRL and predict foetal age was 49.4 days (9 weeks of gestational age). Our results open the way to the detection of foetal growth abnormalities using CRL Zscores throughout the first trimester

Microsatellites for the marsh fritillary butterfly: de novo transcriptome sequencing, and a comparison with amplified fragment length polymorphism (AFLP) markers.

Journal ArticleResearch Support, Non-U.S. Gov'tBACKGROUND: Until recently the isolation of microsatellite markers from Lepidoptera has proved troublesome, expensive and time-consuming. Following on from a previous study of Edith's checkerspot butterfly, Euphydryas editha, we developed novel microsatellite markers for the vulnerable marsh fritillary butterfly, E. aurinia. Our goal was to optimize the process in order to reduce both time and cost relative to prevailing techniques. This was accomplished by using a combination of previously developed techniques: in silico mining of a de novo assembled transcriptome sequence, and genotyping the microsatellites found there using an economic method of fluorescently labelling primers. PRINCIPAL FINDINGS: In total, we screened nine polymorphic microsatellite markers, two of which were previously published, and seven that were isolated de novo. These markers were able to amplify across geographically isolated populations throughout Continental Europe and the UK. Significant deviations from Hardy-Weinberg equilibrium were evident in some populations, most likely due to the presence of null alleles. However, we used an F(st) outlier approach to show that these markers are likely selectively neutral. Furthermore, using a set of 128 individuals from 11 populations, we demonstrate consistency in population differentiation estimates with previously developed amplified fragment length polymorphism (AFLP) markers (r = 0.68, p<0.001). SIGNIFICANCE: Rapid development of microsatellite markers for difficult taxa such as Lepidoptera, and concordant results with other putatively neutral molecular markers, demonstrate the potential of de novo transcriptional sequencing for future studies of population structure and gene flow that are desperately needed for declining species across fragmented landscapes.BBSRCOkinawa Institute for Science and Technology (OIST

Calcifediol is a safe and effective metabolite for raising vitamin D status and improving growth and feed conversion in rainbow trout

The vitamin D endocrine system is required for the transcriptional regulation of a myriad of vertebrate genes including those involved in bone health, growth, nutrient metabolism and immunity. The requirements of salmonids for vitamin D are amongst the highest for any aquaculture species. With nuances, the metabolism of the pre-vitamin cholecalciferol (D3) via calcifediol (25-OH-D3), required to produce the physiologically active hormone calcitriol (1,25-OH-D3) is conserved in fish. The composition of modern aquafeeds, growth in seawater and production challenges, such as disease, may result in the suboptimal biochemical activation of vitamin D hormone in fish. A 91-day experimental feeding trial was used to test the safety and efficacy of calcifediol for the supply of vitamin D to rainbow trout with an initial body weight of 57.6 g. A practical diet containing cholecalciferol within recommended levels (5240 IU) was supplemented with either 69.8, 687 or 6854 μg/kg calcifediol. The efficacy of calcifediol was determined by the assessment of zootechnical performance and the appearance of vitamin D metabolites in the blood. The safety of the dietary interventions was assessed from generic health indices, examination of gross pathologies, hematology, and blood chemistry. Test fish increased body weight at least 5.6-fold to 323.5 g over the experimental feeding period. The supplementation of 687 or 6854 μg/kg calcifediol resulted in significant improvements in growth rate and feed conversion (FCR). Whilst not detectable in control fish, calcifediol increased linearly according to dietary levels in the blood and to a lesser extent in the white muscle. The increases of calcifediol in the blood were accompanied by saturable increases of circulating active vitamin D. At the end of the 91-day feeding period, survival was 100%, no gross pathologies relating to the diets were observed, and health indices, hematology, and blood chemistry, including calcium and phosphorus, were not significantly altered. The supplementation of calcifediol to practical diets containing recommended levels of cholecalciferol improves zootechnical performance and ensures that maximal levels of active vitamin D are present in the blood to meet physiological demands. With a lack of significant effects on health indices, hematology, and blood chemistry, including calcium and phosphorus, the tested high doses of calcifediol are concluded to be safe for salmonids