230 research outputs found
A Simple Three-Parameter Model Potential For Diatomic Systems: From Weakly and Strongly Bound Molecules to Metastable Molecular Ions
Based on a simplest molecular orbital theory of H, a
three-parameter model potential function is proposed to describe ground-state
diatomic systems with closed-shell and/or S-type valence-shell constituents
over a significantly wide range of internuclear distances. More than 200 weakly
and strongly bound diatomics have been studied, including neutral and
singly-charged diatomics (e.g., H, Li, LiH, Cd, Na,
and RbH), long-range bound diatomics (e.g., NaAr, CdNe, He, CaHe,
SrHe, and BaHe), metastable molecular dications (e.g., BeH, AlH,
Mg, and LiBa), and molecular trications (e.g., YHe
and ScHe).Comment: 5 pages, 4 figures, accepted by Physical Review Letter
Bound -> free and bound -> bound multichannel emission spectra from selectively excited Rydberg states in the ZnAr and CdAr van der Waals complexes
Multichannel dispersed emission spectra recorded upon a selective excitation
of Rydberg electronic energy states in the ZnAr and CdAr van der Waals (vdW)
complexes are analysed as a proof-of-concept of the future experimental
approach. Simulations of the emission spectra are based on ab-initio calculated
interatomic potentials and transition dipole moments (TDMs). Experimental
set-up that is under construction along with the experimental procedure are
discussed
Entanglement of single-photons and chiral phonons in atomically thin WSe
Quantum entanglement is a fundamental phenomenon which, on the one hand,
reveals deep connections between quantum mechanics, gravity and the space-time;
on the other hand, has practical applications as a key resource in quantum
information processing. While it is routinely achieved in photon-atom
ensembles, entanglement involving the solid-state or macroscopic objects
remains challenging albeit promising for both fundamental physics and
technological applications. Here, we report entanglement between collective,
chiral vibrations in two-dimensional (2D) WSe host --- chiral phonons (CPs)
--- and single-photons emitted from quantum dots (QDs) present in it. CPs which
carry angular momentum were recently observed in WSe and are a
distinguishing feature of the underlying honeycomb lattice. The entanglement
results from a "which-way" scattering process, involving an optical excitation
in a QD and doubly-degenerate CPs, which takes place via two indistinguishable
paths. Our unveiling of entanglement involving a macroscopic, collective
excitation together with strong interaction between CPs and QDs in 2D materials
opens up ways for phonon-driven entanglement of QDs and engineering chiral or
non-reciprocal interactions at the single-photon level
Effect of an audiovisual message for tetanus booster vaccination broadcast in the waiting room
<p>Abstract</p> <p>Background</p> <p>General practitioners (GPs) often lack time and resources to invest in health education; audiovisual messages broadcast in the waiting room may be a useful educational tool. This work was designed to assess the effect of a message inviting patients to ask for a tetanus booster vaccination.</p> <p>Methods</p> <p>A quasi experimental study was conducted in a Belgian medical practice consisting of 6 GPs and 4 waiting rooms (total: 20,000 contacts/year). A tetanus booster vaccination audiovisual message was continuously broadcast for 6 months in 2 randomly selected waiting rooms (intervention group - 3 GPs) while the other 2 waiting rooms remained unequipped (control group - 3 GPs). At the end of the 6-month period, the number of vaccine adult-doses delivered by local pharmacies in response to GPs' prescriptions was recorded. As a reference, the same data were also collected retrospectively for the general practice during the same 6-month period of the previous year.</p> <p>Results</p> <p>During the 6-month reference period where no audiovisual message was broadcast in the 4 waiting rooms, the number of prescriptions presented for tetanus vaccines was respectively 52 (0.44%) in the intervention group and 33 (0.38%) in the control group (p = 0.50). By contrast, during the 6-month study period, the number of prescriptions differed between the two groups (p < 0.0001), rising significantly to 91 (0.79%) in the intervention group (p = 0.0005) while remaining constant in the control group (0.38% vs 0.39%; p = 0.90).</p> <p>Conclusions</p> <p>Broadcasting an audiovisual health education message in the GPs' waiting room was associated with a significant increase in the number of adult tetanus booster vaccination prescriptions delivered by local pharmacies.</p
Loss of the Orphan Nuclear Receptor SHP Is More Pronounced in Fibrolamellar Carcinoma than in Typical Hepatocellular Carcinoma
Hepatocellular carcinoma (HCC) remains a major problem in oncology. The molecular mechanisms which underlie its pathogenesis are poorly understood. Recently the Small Heterodimer Partner (SHP), an orphan nuclear receptor, was suggested to be involved as a tumor suppressor in hepatocellular carcinoma development. To date, there are no such studies regarding fibrolamellar carcinoma, a less common variant of HCC, which usually affects young people and displays distinct morphological features. The aim of our project was to evaluate the SHP levels in typical and fibrolamellar hepatocellular carcinoma with respect to the levels of one of the cell cycle regulators, cyclin D1. We assessed the immunoreactivity levels of SHP and cyclin D1 in 48 typical hepatocellular carcinomas, 9 tumors representing the fibrolamellar variant, 29 non malignant liver tissues and 7 macroregenerative nodules. We detected significantly lower SHP immunoreactivity in hepatocellular carcinoma when compared to non malignant liver tissue. Moreover, we found that SHP immunoreactivity is reduced in fibrolamellar carcinoma when compared to typical hepatocellular carcinoma. We also found that SHP is more commonly lost in HCC which arises in the liver with steatosis. The comparison between the cyclin D1 and SHP expression revealed the negative correlation between these proteins in the high grade HCC. Our results indicate that the impact of loss of SHP protein may be even more pronounced in fibrolamellar carcinoma than in a typical form of HCC. Further investigation of mechanisms through which the loss of SHP function may influence HCC formation may provide important information in order to design more effective HCC therapy
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