Influence of new reaction rates on 18F production in novae

Gamma-ray emission from classical novae is dominated, during the first hours, by positron annihilation resulting from the beta decay of radioactive nuclei. The main contribution comes from the decay of 18F and hence is directly related to 18F formation during the outburst. A good knowledge of the nuclear reaction rates of production and destruction of 18F is required to study 18F synthesis in novae and the resulting gamma-ray emission. The rates relevant for the main mode of 18F destruction (i.e, through proton captures) have been the object of many recent experiments. However, subsequent analyses were focused on providing rates for X-ray burst nucleosynthesis not valid at nova temperatures (lower than 3.5 10^8 K). Accordingly, it is crucial to propose and discuss new reaction rates, incorporating all new experimental results, down to the domain of nova nucleosynthesis. We show that in this temperature regime, the 18F(p,gamma) and (p,alpha) reaction rates remain uncertain and deserve further experimental and theoretical efforts. Our hydrodynamic calculations including the new nuclear rates demonstrate that their impact on 18F synthesis in nova explosions is quite large and, consequently, the early gamma-ray emission from classical novae is also affected.Comment: To appear in Astron. Astrophys., 14 pages with 9 figure

Culture sonore en chantier : le chantier comme milieu révélateur des modes de professionnalisation

L'objet de cette recherche consiste en la description de la culture professionnelle implicite et informelle liée à l'activité réelle du travail de chantier, en réduisant le champ d'étude à l'environnement sonore. C'est sur la base d'une approche ethno-sociologique de l'environnement sonore du chantier que cette culture professionnelle est abordée

American Branch Report 1996

The seventh annual dinner of the American branch was held at the I Matti restaurant in Washington, D.C. on 29 December 1996. There was no formal programme, but the traditional toast was offered and greetings were delivered from members who could not attend. Those present particularly appreciated the messages from Kathleen and Bill Adams and from Harriet Williams. While we enjoyed excellent Italian food, there was lively conversation about recent works on George Eliot, film versions of various nineteenth-century novels, and our own projects and recent reading. Those in attendance were Marjorie Goss, Shoshana Knapp, Lee Pierson, Meri-Jane Rochelson, Ed Smith, and Linda K. Robertson. Ed Smith volunteered to prepare a Special Session proposal on George Eliot for next year\u27s Modern Language Association convention in Toronto

Frequency Doubling Nanocrystals for Cancer Theranostics

A novel bio-photonics approach based on the nonlinear optical process of second harmonic generation by non-centrosymmetric nanoparticles is presented and demonstrated on malignant human cell lines. The proposed method allows to directly interact with DNA in absence of photosensitizing molecules, to enable independent imaging and therapeutic modalities switching between the two modes of operation by simply tuning the excitation laser wavelength, and to avoid any risk of spontaneous activation by any natural or artificial light source.Comment: 16 pages, 7 figure

073 Right Ventricle Contractile Reserve as a Pre-operative Tool for Assessing RV failure after Continuous Flow LVAD Implantation

IntroductionLatest generation continuous flow left ventricular assist devices (LVADs) have been proposed as an alternative to heart transplantation for end-stage heart failure. However, postoperative right ventricle (RV) dysfunction remains common and has a negative impact on prognosis. Purpose of our study was to identify echocardiographic or hemodynamic parameters that could predict early RV failure after LVAD implantation in patients with biventricular dysfunction.MethodsFourteen patients with biventricular dysfunction who have been evaluated for LVAD implantation were included. Right and left ventricular dysfunction were respectively defined as: tricuspid annular plane excursion < 16 mm (TAPSE) and LV ejection fraction < 35%. In all patients, preoperative measurements were obtained at rest. In 7 patients, right heart catheterization was performed simultaneously with increasing doses of dobutamine (15γ/Kg/min). Primary endpoint was death caused by right ventricle systolic dysfunction or need for right ventricle mechanical support within 30 days after surgery (RVSD+).ResultsMean recipient age was 58±7 years. Primary end-point (RVSD+) was noted in five patients. Preoperative demographic, echocardiographic and hemodynamic data were similar between RVSD+ and RVSD- patients (Table). Percent increase of TAPSE and systolic PAP between basal and high dobutamine dose was significantly lower in RVSD+ than in RVSD- patients.ConclusionPercent increase of TAPSE and systolic PAP induced by high dose dobutamine infusion might be two interesting criteria to assess RV contractile reserve and predict RV outcome after LVAD implantation in patient with biventricular dysfunction.Baseline Measurement (n=14)Change after Dobutamine infusion,% (n=7)RVSD-RVSD+pRVSD-RVSD+pN95TAPSE, mm14±214±20.955±526±20.03Systolic PAP, mmHg51±753±60.842±84±70.05Cardiac Output, l/min3.3±0.53.5±0.50.987±1093±470.7Pulm Vasc Res, Wood3.9±14.3±10.62±41-36±70.

Exploring glycopeptide-resistance in Staphylococcus aureus: a combined proteomics and transcriptomics approach for the identification of resistance-related markers

BACKGROUND: To unravel molecular targets involved in glycopeptide resistance, three isogenic strains of Staphylococcus aureus with different susceptibility levels to vancomycin or teicoplanin were subjected to whole-genome microarray-based transcription and quantitative proteomic profiling. Quantitative proteomics performed on membrane extracts showed exquisite inter-experimental reproducibility permitting the identification and relative quantification of >30% of the predicted S. aureus proteome. RESULTS: In the absence of antibiotic selection pressure, comparison of stable resistant and susceptible strains revealed 94 differentially expressed genes and 178 proteins. As expected, only partial correlation was obtained between transcriptomic and proteomic results during stationary-phase. Application of massively parallel methods identified one third of the complete proteome, a majority of which was only predicted based on genome sequencing, but never identified to date. Several over-expressed genes represent previously reported targets, while series of genes and proteins possibly involved in the glycopeptide resistance mechanism were discovered here, including regulators, global regulator attenuator, hyper-mutability factor or hypothetical proteins. Gene expression of these markers was confirmed in a collection of genetically unrelated strains showing altered susceptibility to glycopeptides. CONCLUSION: Our proteome and transcriptome analyses have been performed during stationary-phase of growth on isogenic strains showing susceptibility or intermediate level of resistance against glycopeptides. Altered susceptibility had emerged spontaneously after infection with a sensitive parental strain, thus not selected in vitro. This combined analysis allows the identification of hundreds of proteins considered, so far as hypothetical protein. In addition, this study provides not only a global picture of transcription and expression adaptations during a complex antibiotic resistance mechanism but also unravels potential drug targets or markers that are constitutively expressed by resistant strains regardless of their genetic background, amenable to be used as diagnostic targets

Assessing the dynamics of organic aerosols over the North Atlantic Ocean

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scientific Reports 7 (2017): 45476, doi:10.1038/srep45476.The influence of aerosols on climate is highly dependent on the particle size distribution, concentration, and composition. In particular, the latter influences their ability to act as cloud condensation nuclei, whereby they impact cloud coverage and precipitation. Here, we simultaneously measured the concentration of aerosols from sea spray over the North Atlantic on board the exhaust-free solar-powered vessel “PlanetSolar”, and the sea surface physico-chemical parameters. We identified organic-bearing particles based on individual particle fluorescence spectra. Organic-bearing aerosols display specific spatio-temporal distributions as compared to total aerosols. We propose an empirical parameterization of the organic-bearing particle concentration, with a dependence on water salinity and sea-surface temperature only. We also show that a very rich mixture of organic aerosols is emitted from the sea surface. Such data will certainly contribute to providing further insight into the influence of aerosols on cloud formation, and be used as input for the improved modeling of aerosols and their role in global climate processes.We gratefully acknowledge the financial support by the H. Dudley Wright and the Henri Moser Foundations, the Rector’s Office and the Institute for Environmental Sciences at the University of Geneva, as well as a generous anonymous donator