35 research outputs found
Deformation of the N=Z nucleus 76Sr using beta-decay studies
A novel method of deducing the deformation of the N=Z nucleus 76Sr is
presented. It is based on the comparison of the experimental Gamow-Teller
strength distribution B(GT) from its beta decay with the results of QRPA
calculations. This method confirms previous indications of the strong prolate
deformation of this nucleus in a totally independent way. The measurement has
been carried out with a large Total Absorption gamma Spectrometer, "Lucrecia",
newly installed at CERN-ISOLDE.Comment: Accepted in Phys. Rev. Letter
New Lidocaine-Based Pharmaceutical Cocrystals: Preparation, Characterization, and Influence of the Racemic vs. Enantiopure Coformer on the Physico-Chemical Properties
This study describes the preparation, characterization, and influence of the enantiopure vs. racemic coformer on the physico-chemical properties of a pharmaceutical cocrystal. For that purpose, two new 1:1 cocrystals, namely lidocaine:dl-menthol and lidocaine:d-menthol, were prepared. The menthol racemate-based cocrystal was evaluated by means of X-ray diffraction, infrared spectroscopy, Raman, thermal analysis, and solubility experiments. The results were exhaustively compared with the first menthol-based pharmaceutical cocrystal, i.e., lidocaine:l-menthol, discovered in our group 12 years ago. Furthermore, the stable lidocaine/dl-menthol phase diagram has been screened, thoroughly evaluated, and compared to the enantiopure phase diagram. Thus, it has been proven that the racemic vs. enantiopure coformer leads to increased solubility and improved dissolution of lidocaine due to the low stable form induced by menthol molecular disorder in the lidocaine:dl-menthol cocrystal. To date, the 1:1 lidocaine:dl-menthol cocrystal is the third menthol-based pharmaceutical cocrystal, after the 1:1 lidocaine:l-menthol and the 1:2 lopinavir:l-menthol cocrystals reported in 2010 and 2022, respectively. Overall, this study shows promising potential for designing new materials with both improved characteristics and functional properties in the fields of pharmaceutical sciences and crystal engineering
COMPLIS experiments : COllaboration for spectroscopy Measurements using a Pulsed Laser Ion Source
Laser spectroscopy measurements have been carried out on very neutron-deficient isotopes of Au, Pt and Ir, produced as daughter elements from a Hg ISOLDE beam. For these transitional region nuclides, the hyperfine structure (HFS) and isotope shift (IS) were measured by Resonance Ionization Spectroscopy (RIS). Magnetic moments ÎŒ, spectroscopic quadrupole moments Qs and changes of the nuclear mean square charge radius ÎŽărc 2ăalong isotopic series have been extracted. For some results, a detailed comparison with theoretical predictions is presented. (Springer
The <i>Ectocarpus</i> genome and the independent evolution of multicellularity in brown algae
Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related1. These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. Brown algae are also one of only a small number of eukaryotic lineages that have evolved complex multicellularity (Fig. 1).We report the 214 million base pair (Mbp) genome sequence of the filamentous seaweed Ectocarpus siliculosus (Dillwyn) Lyngbye, a model organism for brown algae, closely related to the kelps (Fig. 1). Genome features such as the presence of an extended set of light-harvesting and pigment biosynthesis genes and new metabolic processes such as halide metabolism help explain the ability of this organism to cope with the highly variable tidal environment. The evolution of multicellularity in this lineage is correlated with the presence of a rich array of signal transduction genes. Of particular interest is the presence of a family of receptor kinases, as the independent evolution of related molecules has been linked with the emergence of multicellularity in both the animal and green plant lineages. The Ectocarpus genome sequence represents an important step towards developing this organism as a model species, providing the possibility to combine genomic and genetic2 approaches to explore these and other aspects of brown algal biology further
Identification of Tâcell epitopes from benzylpenicillin conjugated to human serum albumin and implication in penicillin allergy
International audienceAbstract Background There is in vitro evidence that T cells from allergic patients react to benzylpenicillinâhuman serum albumin ( BP â HSA ) bioconjugates. Our group has recently shown the existence of naĂŻve CD 4 + T cells recognizing BP â HSA in healthy donors. However, BP âhaptenated peptides from HSA participating in the immunization of allergic patients have never been identified. The purpose of the present study is to identify immunodominant BP âhaptenated peptides from HSA involved in immunization of patients to BP and to refine the frequency calculation of naĂŻve CD 4 + T cells recognizing BP . Methods Coâcultures were established with CD 4 + T cells from nonâallergic donors and mature autologous dendritic cells ( DC s) loaded with BP â HSA or BP âhaptenated peptides from HSA . The CD 4 + Tâcell response specific for BP â HSA or for individual BP âhaptenated peptides was measured using an interferonâÎł ( IFN âÎł) ELIS pot assay. The frequency of BP âspecific CD 4 + T cells was then calculated using the Poisson distribution. BP â HSA and BP âhaptenated peptides recognition by allergic patients was evaluated on peripheral blood mononuclear cells ( PBMC s) using a lymphocyte transformation test ( LTT ). Results Results showed that BP â HSA and BP âhaptenated peptides were recognized by naĂŻve T cells from 15/16 and 13/14 tested healthy donors, respectively. Most donors responded to 3 peptides with BP covalently bound on lysines 159, 212, and 525. Two of these benzylpenicilloylated peptides (lysines 159 and 525) were also found to induce PBMC s proliferation in patients with allergic reaction to penicillins. Conclusion This study identifies and characterizes for the first time the BP âhaptenated peptides from HSA involved in the immunization of patients to penicillins
Laser spectroscopy measurements of neutron-rich tellurium isotopes by COMPLIS
Laser spectroscopy based on resonant ionization of laser-desorbed atoms has been used to study the neutron-rich tellurium isotopes with the COMPLIS facility at ISOLDE-CERN. Isotope shifts and hyperfine structures of several neutron-rich Te isotopes: Te and Te have been measured. From the hyperfine structure we have extracted magnetic and quadrupole moments. Changes in the mean square charge radii have been deduced and their comparison with the known data for the other elements near Zâ=â50 is presented. The experimental â values are compared with those obtained from relativistic mean field calculations
Laser Spectroscopy Measurement of Neutron-Rich Tellurium Isotopes by COMPLIS
Laser spectroscopy based on resonant ionization of laser-desorbed atoms has been used to study the neutron-rich tellurium isotopes with the COMPLIS facility at ISOLDE-CERN. Isotope shifts and hyperfine structures of several neutron-rich Te isotopes: Te and Te have been measured. From the hyperfine structure we have extracted magnetic and quadrupole moments. Changes in the mean square charge radii have been deduced and their comparison with the known data for the other elements near Zâ=â50 is presented. The experimental â values are compared with those obtained from relativistic mean field calculations