Br J Haematol

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La Faculté de Médecine sous l’Occupation (1939-1944)

info:eu-repo/semantics/published

Modelling radiative properties of gas mixtures in nonequilibrium high-altitude rocket plumes

International audienceThis paper presents the development of a Statistical Narrow Band model (SNB) in a nonequilibrium vibrational state for HCl and CO molecules. The population densities of the energy levels are obtained by a multi-temperature approach to compute nonequilibrium Line By Line (LBL) spectra. The SNB parameters are obtained by fitting the curves of growth from the LBL approach by a least squares error minimization using a Newton method for pure Lorentz and Doppler broadening regimes. The model is tested in Voigt broadening regime using a mixing rule and agrees well with the LBL approach. Finally, spectral correlation problems between η_σ /κ_σ and κ_σ , where η_σ and κ_σ are the emission and absorption coefficients respectively, have been exhibited for CO_2

Nanocrystals of Fe(phen)(2)(NCS)(2) and the size-dependent spin-crossover characteristics

International audienceWe report on the size reduction of the neutral Fe(phen)(2)(NCS)(2) prototypical compound exhibiting a cooperative spin-crossover associated with a first-order phase transition (at ca. 176 K). We use the [Fe(phen)(3)](NCS)(2) ionic precursor and the solvent-assisted precipitation technique to prepare an array of crystalline objects with sizes varying over two orders of magnitude (from 15 up to 1400 nm). TEM, X-ray diffraction and IR measurements provide evidences for the formation of particles of neutral and ionic species, which results from the interplay between the relevant chemical equilibrium and the reaction kinetics (ligand extraction, complex precipitation), and the modulation of the latter by physico-chemical parameters. A thermal transformation of diamagnetic nanocrystals of [Fe(phen)(3)](NCS)(2) leads to spin-crossover particles of Fe(phen)(2)(NCS)(2) of a comparable size. Powders of nano-, micro-and polycrystals of Fe (phen)(2)(NCS)(2) present X-ray diffractograms typical of the so-called polymorph II. The importance of size effects on the cooperative spin-crossover process was probed with magnetic, Mossbauer, Raman and IR spectroscopic measurements. Each sample exhibits spin-state switching of the Fe(II) ions. The salient features are: a cooperativity preserved at the micrometric scale, a very limited downshift of the transition temperature and an asymmetric spreading of the thermal process (over ca. 100 K) with the size reduction. At temperatures close to room temperature, the process appears to be quasi complete whatever the size of the samples. This result, extracted from Raman data, was confirmed by Mssbauer measurements in the case of the largest objects (LS residue <5-10% for bulk and microparticles). Below 150 K, a very efficient low-spin to high-spin photoexcitation was induced by the Raman laser beam in all the samples which prevents the extraction of the high-spin fraction in this temperature range. However variable temperature IR spectra of the 29 nm particles indicate that the HS residue, that is close to zero in the case of microparticles, does not drastically increase (<30%) for the smallest particles. The processing of a number of related spin-crossover compounds in the form of nanoparticles may be achieved with this general approach

Fe(Me-2-bpy)(2)(NCSe)(2) spin-crossover micro- and nanoparticles showing spin-state switching above 250 K

International audienceWe present the study of nano- and microparticles of the Fe(Me-2-bpy)(2)(NCSe)(2) spin-crossover complex prepared from the diamagnetic precursor [Fe(Me-2-bpy)(3)](NCSe)(2)center dot S. Two solvates of the latter were characterized by single-crystal X-ray structures at 100 K (S = 2MeOH or 3H(2)O). The extraction of one Me-2-bpy per metal ion in [Fe(Me-2-bpy)(3)](NCSe)(2)center dot S was achieved either by thermolysis at temperature higher than 150 degrees C or by precipitation in an anti-solvent, leading to a polycrystalline or particulate powder of Fe(Me-2-bpy)(2)(NCSe)(2). This chemical conversion was investigated by TGA, powder X-ray diffraction, IR, Raman and magnetic measurements. The S = 0 S = 2 spin-crossover of Fe(Me-2-bpy)(2)-(NCSe)(2) centered at ca. 340 K is almost complete at low temperature (HS residue <= 5% below 250 K) while at 370 K, the HS fraction can be estimated at similar to 0.7. These features are essentially preserved whatever be the size of particles (56, 460 and 1200 nm) as a consequence of the weak cooperativity of the process occurring at high temperature, the crystallinity and the molecular nature of particles. This approach leading to dispersion of small particles in a polymer is suitable for the preparation of materials of optical quality, via the stabilization and processing of nanoparticles in convenient matrices to form thin films

Sanger and Next-Generation Sequencing data for characterization of CTL epitopes in archived HIV-1 proviral DNA.

One of the strategies for curing viral HIV-1 is a therapeutic vaccine involving the stimulation of cytotoxic CD8-positive T cells (CTL) that are Human Leucocyte Antigen (HLA)-restricted. The lack of efficiency of previous vaccination strategies may have been due to the immunogenic peptides used, which could be different from a patient's virus epitopes and lead to a poor CTL response. To counteract this lack of specificity, conserved epitopes must be targeted. One alternative is to gather as many data as possible from a large number of patients on their HIV-1 proviral archived epitope variants, taking into account their genetic background to select the best presented CTL epitopes. In order to process big data generated by Next-Generation Sequencing (NGS) of the DNA of HIV-infected patients, we have developed a software package called TutuGenetics. This tool combines an alignment derived either from Sanger or NGS files, HLA typing, target gene and a CTL epitope list as input files. It allows automatic translation after correction of the alignment obtained between the HxB2 reference and the reads, followed by automatic calculation of the MHC IC50 value for each epitope variant and the HLA allele of the patient by using NetMHCpan 3.0, resulting in a csv file as output result. We validated this new tool by comparing Sanger and NGS (454, Roche) sequences obtained from the proviral DNA of patients at success of ART included in the Provir Latitude 45 study and showed a 90% correlation between the quantitative results of NGS and Sanger. This automated analysis combined with complementary samples should yield more data regarding the archived CTL epitopes according to the patients' HLA alleles and will be useful for screening epitopes that in theory are presented efficiently to the HLA groove, thus constituting promising immunogenic peptides for a therapeutic vaccine

Al-Arid, an Early Bronze Age settlement site in the interior of the Oman peninsula. Results of the second season’s excavations (2020)

International audienceFollowing a first season of joint investigations carried out at the two settlement sites of Bāt and al-Arid (15 km north-west of Bāt) in the Sultanate of Oman, during winter 2019 (Castel et al. 2020), the MBA Mission (Mission archéologique de Bāt/al-Arid) carried out a second season of excavations at the settlement site of al-Arid in 2020.This contribution aims to present the latest results from this extensive survey, the excavations, and the different studies ofthis new mission carried out by a multidisciplinary team of specialists. Three structures were excavated: one of seven towers, with a regular internal plan; a tomb that yielded a Jemdet-Nasr plain vessel and an Umm an-Nar Black-on-Red Fine Ware pot; and a building assigned to the late Umm an-Nar period. In addition, the investigations carried out on two abandoned irrigation canals, one of which may be related to the Bronze Age settlement, were continued. The first results obtained from the analysis of the pottery are presented and the Bayesian chronological analysis makes it possible to place all the radiocarbon dated events in the regional chronology. All these combined results shed new light on the al-Arid site and enable us to refine its chronology, thus enriching the debate on third-millennium settlement patterns in the southern piedmont region of interior Oman.Keywords: Oman, Hafit, Umm an-Nar, tower, irrigation cana

Patients’ characteristics.

<p>The viral clade and HLA allele A and B typing results for each individual from the French, Canadian or Peruvian cohort are presented.</p