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Compact polyethylenimine-complexed mRNA vaccines
No full textHere we describe formulations comprising individual, polymer-complexed self-amplifying RNA (saRNA) molecules, designed for vaccination against infectious diseases and other prophylactic and therapeutic applications. When exposed to a large excess of the cationic polymer polyethylenimine (PEI), the single saRNA molecules in solution reorganize from an extended to a globular organization, characterized by a high packing density, low polymer mass fraction and, consequently, a very small size of the polyplex nanoparticles of about 30 nm. This format of PEI-complexed saRNA exhibits enhanced biological activity in comparison with previously described saRNA/PEI formulations, both in vitro and in vivo. In vaccination models, relevant immune responses at lower doses are achieved, offering potential advantages for practical use. We found that the single PEI-complexed RNA molecules are also present in conventional formulations to some degree. The direct correlation between the single-molecule fraction with activity suggests that it is this format that predominantly contributes to activity in the different formulation types. Complexation is driven by mechanisms of self-assembly between oppositely charged polyelectrolytes, making this protocol broadly applicable to various cationic polymers and RNA constructs. With their small size and good stability in biofluids, these compacted RNA molecules are also promising for the systemic delivery of genetic material to compartments that are difficult to reach with larger particles
Observation of production in collisions at = 13 TeV with the ATLAS detector and constraints on anomalous quartic gauge-boson couplings
No full textThis Letter reports the observation of triboson production in 140 fb of data collected by the ATLAS detector from proton-proton collisions at a centre-of-mass energy of = 13 TeV at the LHC. Events with an opposite-charge pair, a high transverse-momentum photon, and significant missing transverse momentum are considered. The observed (expected) significance of the signal is 5.9 (6.0) standard deviations. The measured fiducial cross-section, defined for the final state is 6.2 0.8 (stat.) 0.6 (sys.) fb, in good agreement with the Standard Model prediction of 6.1 fb. Constraints on the Wilson coefficients of 13 dimension-8 operators describing physics beyond the Standard Model through anomalous quartic gauge-boson couplings are derived using the effective field theory framework
Inching toward the QCD axions with axion magnetic resonance in helioscopes
No full textUtilizing a helical magnet profile to enhance axion-photon conversion showed great promise in laboratory searches for high axion masses. We extend the mechanism, known as the axion-magnetic resonance (AMR), from laser experiments to axion helioscopes and demonstrate its potential in covering QCD axion parameter space. Specifically, we apply AMR to the CAST experiment legacy, make projections for the upcoming IAXO experiment, and assess its implications for both axion-like particles and QCD axions. We observe considerable improvement in the experiment’s sensitivity reach in all cases
Combined dark matter search towards dwarf spheroidal galaxies with Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS
No full textDwarf spheroidal galaxies (dSphs) are excellent targets for indirect dark matter (DM) searches using gamma-ray telescopes because they are thought to have high DM content and a low astrophysical background. The sensitivity of these searches is improved by combining the observations of dSphs made by different gamma-ray telescopes. We present the results of a combined search by the most sensitive currently operating gamma-ray telescopes, namely: the satellite-borne Fermi-LAT telescope; the ground-based imaging atmospheric Cherenkov telescope arrays H.E.S.S., MAGIC, and VERITAS; and the HAWC water Cherenkov detector. Individual datasets were analyzed using a common statistical approach. Results were subsequently combined via a global joint likelihood analysis. We obtain constraints on the velocity-weighted cross section for DM self-annihilation as a function of the DM particle mass. This five-instrument combination allows the derivation of up to 2-3 times more constraining upper limits on than the individual results over a wide mass range spanning from 5 GeV to 100 TeV. Depending on the DM content modeling, the 95% confidence level observed limits reach 10 cms and 10 cms, respectively, in the annihilation channel for a DM mass of 2 TeV
Eventdisplay: An Analysis and Reconstruction Package for Ground-based Gamma-ray Astronomy
No full textEventdisplay is a reconstruction and analysis pipeline for data of Imaging Atmospheric Cherenkov Telescopes (IACT). It has been primarily developed for VERITAS and CTA analysis. Code, analysis files and scripts can be find in the Eventdisplay GitHub Organisation. Docker images are available from the Eventdisplay container registry. In case Eventdisplay is used in a research project, please cite the following publication: Maier, G.; Holder, J., Eventdisplay: An Analysis and Reconstruction Package for Ground-based Gamma-ray Astronomy, 35th International Cosmic Ray Conference. 10-20 July, 2017. Bexco, Busan, Korea, Proceedings of Science, Vol. 301. Online at [https://pos.sissa.it/cgi-bin/reader/conf.cgi?confid=301], id.747 arXiv:1708.04048 This is a small improvement release allowing to run the prod5 analysis with an increased integration window of 30ns. What's Changed Bump docker/build-push-action from 5 to 6 by @dependabot in https://github.com/Eventdisplay/Eventdisplay/pull/170 Bump actions/checkout from 2 to 4 by @dependabot in https://github.com/Eventdisplay/Eventdisplay/pull/169 5.15.0 dev1 by @GernotMaier in https://github.com/Eventdisplay/Eventdisplay/pull/172 Add 30ns run options by @GernotMaier in https://github.com/Eventdisplay/Eventdisplay/pull/173 New Contributors @dependabot made their first contribution in https://github.com/Eventdisplay/Eventdisplay/pull/170 Full Changelog: https://github.com/Eventdisplay/Eventdisplay/compare/v5.14.0...v5.15.
Unraveling the structural phase transition and its effect on photophysical properties of mechanochemically synthesized CHNHPbBr
No full textThe mechanochemical synthesis route has become popular for the solvent-free synthesis of a wide range of hybrid halide perovskites. This work demonstrates that mechanochemically synthesized CHNHPbBr is thermally more stable compared to chemically processed material and free from deep-level defects. Temperature-dependent structural study on mechanochemically synthesized material reveals that it exhibits a cubic phase at room temperature with a phase transition from cubic to tetragonal phase at 230 K. Below 150 K, it transforms into an orthorhombic phase, which belongs to an incommensurately modulated crystal structure (Imma(s00)00γ). Unlike the early reports, the orthorhombic Pnma structure is absent, and the modulated phase is extended over a wide range of temperatures from 145 K to 100 K. Temperature-dependent photoluminescence study shows that the emission spectrum comprises both the contribution from free and bound excitons. The blueshift of the bandgap with increasing lattice temperature can be explained by the large volume expansion coefficient (of the order 10−4), which dominates over the contribution due to electron–phonon coupling. The linewidth broadening of the emission spectrum is mainly due to the interaction of the longitudinal optical phonon with the free electron. The photo-generated exciton exhibits high activation energy (∼100 meV) at room temperature, demonstrating its potential for light-emitting device applications
Projected Sensitivity to Top-Quark Couplings in and Production at the HL-LHC with the ATLAS Experiment
No full textProjection studies for top quark pair production in association with a photon and a boson at the High Luminosity LHC (HL-LHC) are presented. They focus on the sensitivity of these processes to the electroweak couplings of the top quark, interpreted in the context of Effective Field Theories. The projections are based on extrapolations of the latest Run 2 differential cross section measurements using 140 fb of proton-proton collision data recorded by the ATLAS detector during Run 2 of the LHC. Assuming integrated luminosities of 2 to 3 ab per experiment, and two different uncertainty scenarios, the expected limits on various Effective Field Theory operators from a combination of ATLAS and CMS results are explored
Updated projections for Higgs boson measurements using , and decays and for the combined measurement of Higgs boson couplings with the ATLAS detector at the HL-LHC
No full textUpdated estimates are presented of the expected precision for the Higgs boson measurements in the , and final states with the ATLAS detector at the High Luminosity LHC. The measurements performed in the same final states using the full ATLAS Run 2 data are projected to integrated luminosities ranging from 1000 fb to 3000 fb, at a centre-of-mass energy of 14 TeV. They are obtained in baseline, optimistic and conservative scenarios of systematic uncertainties. In addition, the latest ATLAS extrapolations of single Higgs-boson measurements in the baseline uncertainty scenario with 3000 fb are used in a joint interpretation to derive the expected uncertainties in the scale factors of various Higgs boson coupling strengths
Depth-dependent anisotropy in the Earth’s inner core linked to chemical stratification
No full textSeismic anisotropy in the Earth’s inner core (IC), including the heterogeneous, depth-dependent anisotropy structure, is a well-documented yet poorly understood feature plausibly related to the alignment of iron alloy crystals. Here, we report the effect of silicon and carbon on the plastic deformation of hexagonal close-packed (hcp) iron using radial X-ray diffraction at pressures up to 128 GPa and temperatures up to 1100 K. Our results reveal a low compressional wave anisotropy (~2 %) in the Fe-Si-C alloy, consistent with the seismic anisotropy observed in the outer regions of the IC. These findings, together with the higher anisotropy exhibited by pure hcp-Fe, suggest that the depth-dependent elastic anisotropy of the IC may originate from chemical stratification, i.e., radial gradients in silicon and carbon concentrations, during crystallization