Observing Higgs boson production through its decay into gamma-rays: A messenger for Dark Matter candidates

In this Letter, we study the gamma-ray signatures subsequent to the production of a Higgs boson in space by dark matter annihilations. We investigate the cases where the Higgs boson is produced at rest or slightly boosted and show that such configurations can produce characteristic bumps in the gamma-ray data. These results are relevant in the case of the Standard Model-like Higgs boson provided that the dark matter mass is about 63 GeV, 109 GeV or 126 GeV, but can be generalised to any other Higgs boson masses. Here, we point out that it may be worth looking for a 63 GeV line since it could be the signature of the decay of a Standard Model-like Higgs boson produced in space, as in the case of a di-Higgs final state if m_DM ~ 126 GeV. We show that one can set generic constraints on the Higgs boson production rates using its decay properties. In particular, using the Fermi-LAT data from the galactic center, we find that the dark matter annihilation cross section into gamma + a Standard Model-like Higgs boson produced at rest or near rest cannot exceed ~ a few 10^-25 cm^3/s or ~ a few 10^-27 cm^3/s respectively, providing us with information on the Higgs coupling to the dark matter particle. We conclude that Higgs bosons can indeed be used as messengers to explore the dark matter mass range.Comment: 8 pages, 5 figures. V2: Final version published in PL

Modulation of metallic oxide particle behaviour in a formulation: physicochemical and/or sensory properties of emulsions as a tool to identify particles interactions within the matrix

International audienceParticles of metal oxides such as silica (SiO2), alumina (Al2O3) or titanium dioxide (TiO2) are nowadays widely used in manufactured products. The interest of these solid particles lies in the possibility tovary their size (a few nanometers to several micrometers), their shape, and their state of aggregation, as well as their specific surface. In addition, these metal oxides are good candidates for surface modification (coating with other metal oxides, silanization) to also modulate their surface properties [1-2].Thus, incorporated in a complex medium such as an emulsion, these solid particles, due to their varied physicochemical properties, will be able to interact with all the constituents of the matrix. This represents asubject of great scientific interest, from both applied and fundamental point of view. Depending on its surface properties, the particle can manifest more affinity with the continuous phase, the dispersedone, or can be placed at the interface [3]. In the latter situation, the particle can act as a surfactant and can even replace the molecular surfactants conventionally used.The aim of this study lays on its multiscale approach: from microscopic scale through the investigation of the ingredients interactions (guided by the type of particle used) to macroscopic scale with the characterization of stable, homogeneous and totally emulsified systems (as it was a required condition to provide an adapted system for macroscopic evaluations). Rheological, textural and sensory behavior, as well as emulsion colloid size and size distribution, were used as a tool to identify the role of the particles on the matrix organization.One objective was to find the emulsions optimal formulation process and composition to accomplish the desired requirements for this study.The obtained results clearly showed the importance of the particle properties in emulsion formation and stabilization. Interactions created inside the matrix were governed by the specific surface andthe coating type of the particles. Thus, the modulation of the emulsion can be possible relying on the particle/emulsifier/oil phase interaction and ratio.[1] S. Björkegren, L. Nordstierna, A. Törncrona and A. Palmqvist, Journal of Colloid and Interface Science, 2017, 487, 250.[2] C. Picard, A. Larbot, E. Tronel-Peyroz and R. Berjoan, Solid State Sciences, 2004, 6, 605.[3] B. P. Binks, Current Opinion in Colloid & Interface Science, 2002, 7, 21

Wenn ein Teil von dir geht… : wie Pflegefachpersonen Eltern von Kindern und Jugendlichen mit onkologischer Erkrankung am Lebensende unterstützen können

Hintergrund: Krebs ist in der Schweiz eine häufige Todesursache bei Kindern. Eltern fühlen sich während der letzten Lebensphase ihres Kindes oft nicht angemessen unterstützt. Zudem empfinden viele Pflegefachpersonen die Kommunikation mit den Eltern in dieser Zeit als herausfordernd und unangenehm. Fragestellung: Wie können Pflegefachpersonen Eltern von Kindern und Jugendlichen mit einer onkologischen Erkrankung in der End-of-life-Phase unterstützen?’ Methode: Auf ‚PubMed’, ‚CINAHL Complete’ und ‚PsycINFO’ wurde eine systematisierte Literaturrecherche durchgeführt. Es wurden vier qualitative Studien, eine quantitative Studie und ein qualitatives Review selektiert, zusammengefasst, kritisch gewürdigt und auf ihre Evidenz geprüft. Anhand des Modells von King (1981) wurde ein Theorie-Praxis-Transfer hergestellt. Relevante Ergebnisse: Aus den inkludierten Studien kristallisierten sich drei Themenbereiche heraus, welche für Pflegefachpersonen essenziell sind: ‚Relevanz von Kommunikation und Hoffnung’, ‚Aufbau und Relevanz von Beziehungen’ sowie ‚Gewährleisten von Kontrolle und Selbstbestimmung’. Schlussfolgerung: Pflegefachpersonen können Eltern von schwerkranken Kindern unterstützen, indem sie offen und ehrlich kommunizieren und Hoffnung aufrechterhalten. Eine empathische und verständnisvolle Pflege stellt einen zentralen Faktor für einen gelingenden Beziehungsaufbau dar. Zudem soll auf die Bedürfnisse der Eltern eingegangen werden, um ihnen ein Gefühl der Kontrolle und Selbstbestimmung zu geben

Monodomain to polydomain transition in ferroelectric PbTiO3 thin films with La0.67Sr0.3MnO3 electrodes

Finite size effects in ferroelectric thin films have been probed in a series of epitaxial perovskite c-axis oriented PbTiO3 films grown on thin La0.67Sr0.33MnO3 epitaxial electrodes. The film thickness ranges from 480 down to 28 A (7 unit cells). The evolution of the film tetragonality c/a, studied using high resolution x-ray diffraction measurements, shows first a decrease of c/a with decreasing film thickness followed by a recovery of c/a at small thicknesses. This recovery is accompanied by a change from a monodomain to a polydomain configuration of the polarization, as directly demonstrated by piezoresponse atomic force microscopy measurements

Landscape of RNA polyadenylation in E-coli

Polyadenylation is thought to be involved in the degradation and quality control of bacterial RNAs but relatively few examples have been investigated. We used a combination of 5 '-tagRACE and RNA-seq to analyze the total RNA content from a wild-type strain and from a poly(A) polymerase deleted Mutant. A total of 178 transcripts were either up- or down-regulated in the mutant when compared to the wild-type strain. Poly(A) polymerase up-regulates the expression of all genes related to the FliA regulon and several previously unknown transcripts, including numerous transporters. Notable down-regulation of genes in the expression of antigen 43 and components of the type 1 fimbriae was detected. The major consequence of the absence of poly(A) polymerase was the accumulation of numerous sRNAs, antisense transcripts, REP sequences and RNA fragments resulting from the processing of entire transcripts. A new algorithm to analyze the position and composition of post-transcriptional modifications based on the sequence of unencoded 3 '-ends, was developed to identify polyadenylated molecules. Overall our results shed new light on the broad spectrum of action of polyadenylation on gene expression and demonstrate the importance of poly(A) dependent degradation to remove structured RNA fragments.Peer reviewe

Effects of aging on structure and stability of TiO2 nanoparticle-containing oil-in-water emulsions

International audienceFormulations incorporating different cosmetic grade TiO 2 nanoparticles were developed according to a self-produced protocol on the basis of typical sunscreen cream oil-in-water emulsions. Role of nanopar-ticles and, more specifically, the impact of two different lipophilic surface treatments on microstructure and stability of the formulations were assessed. Aging of formulations was performed under classical conditions at room temperature or under accelerated conditions at 50 • C, with or without TiO 2 , and was characterized by several tools such as rheology, microscopy, and particle size measurements. Changes in emulsion stability and aggregation state of nanoparticles were followed over time. Destabilization phenomena were identified: under accelerated aging, the formulation without nanoparticles underwent a coalescence occurrence whereas the formulation incorporating nanoparticles was subjected to aggregation of the colloidal particles. Besides, TiO 2 nanoparticles strongly affected the particle-droplets interactions and thus modified the emulsion microstructure with a coating-dependent effect: destabilization mechanisms occur more rapidly with alumina (and) triethoxycaprylylsilane (coating 1) TiO 2 nanoparticles as compared to alumina (and) isopropyl titanium triisostearate (and) triethoxycaprylylsi-lane crosspolymer (coating 2) nanoparticles

PHYSICAL AGING OF EMULSIONS CONTAINING COATED TIO2-NANOPARTICLES: INTERACTION BETWEEN NANOPARTICLES AND OTHER INGREDIENTS

International audienceTiO2-nanoparticles (NPs) are usually added to cosmetic emulsions because they procure a good UV-protection1. In this study, two natures of NPs surfaces were explored: a hydrophilic silica-coated particle and a hydrophobic one covered with a large organic coating. During emulsion aging and depending on their surfacenature and properties, NPs might interact with the formula by inducing adsorption of formula’s compounds2 or by undergoingcoatings damages. These phenomenamay change the nanoparticle surface properties, their behavior in emulsion, and finally, led to the emulsionsdestabilization. The impact of TiO2-NP surfaces on the physical aging of emulsions was here studied.For this purpose, threeemulsions were formulated differing only by the presence and type of NPs: one NP-free as blank, and two containing hydrophilic and hydrophobic commercial TiO2-NPs, respectively.The emulsification process was optimized to obtain a blank emulsion physically stable and to improve the NPs dispersions. Effects of coatings on fresh emulsions were depicted on the micro and macro scales by several physico-chemical methods.Then, emulsions physical evolutions onnormal or accelerate aging conditionswere monitored.Droplets sizes were similar between the three fresh emulsions, whereas slight differences in term of networksorganization highlighted the impact of the coating nature on the emulsion microstructure. However, initial emulsions properties looked similar by applying rheological and textural analyses. Although the blank emulsion and the one with hydrophilic NPs remained similar after the aging step, the microstructure of the emulsion with hydrophobic NPsquickly evolved: aggregates of both droplets and NPs made the formula less homogeneous. As will be illustrated, this evolution in term of colloids sizes strongly affects the functional properties, as viscosity, consistency or spreading quality of this aged emulsion. These results revealed the impact of coating nature in this kind of complex media. Afterinnovative NPs extractions3 from fresh and aged formulae, their surfaces were characterized. By an original physico-chemical approach, quick surface modifications appeared and changed the surface charges and wettability of particles. These variations might cause the differences in term of stability between emulsions.(1) Serpone, N.; Dondi, D.; Albini, A. Inorganica Chim. Acta2007, 360 (3), 794–802.(2) Rossano, M.; Hucher, N.; Picard, C.; Colleta, D.; Le Foll, F.; Grisel, M. Int. J. Pharm.2014, 461 (1-2), 89–96.(3) Rossano, M. Ph.D thesis: Utilisation des nanoparticules de dioxyde de titane dans les émulsions cosmétiques : impact sur la santé humaine et l’environnement, Université du Havre: Le Havre, 2014

Relationship between split-step timing and leg stiffness in world-class tennis players when returning fast serves

International audienc

Using CamiTK for rapid prototyping of interactive Computer Assisted Medical Intervention applications

Computer Assisted Medical Intervention (CAMI hereafter) is a complex multi-disciplinary field. CAMI research requires the collaboration of experts in several fields as diverse as medicine, computer science, mathematics, instrumentation, signal processing, mechanics, modeling, automatics, optics, etc