767 research outputs found
Energy and momentum entanglement in parametric downconversion
We present a simple treatment for the phenomenon of parametric downconversion
considering the coherent scattering of one pump photon into a photon pair by a
nonlinear crystal. The energy and momentum entanglement of the quantum state of
the generated twin photons are seen as a consequence of the fundamental
indistinguishability of the time and the position in which the photon pair is
created inside the crystal. We also discuss some consequences of the system
entanglement.Comment: 6 pages, 2 figures. v3: Minor changes on the text. Some references
were include
Ethanol and erythrocyte membrane interaction : a hemorheologic perspective
© 1999 – IOS Press. All rights reservedPrevious studies have documented structural and functional changes induced by ethanol–erythrocyte membrane interaction.
In order to perform an in vitro study on the effect of different ethanol concentrations on erythrocyte hemorheologic properties, blood samples were collected from 21 male donors at the Hospital of Santa Maria. Whole blood aliquots were incubated with ethanol solutions of rising concentrations. The following parameters were measured: erythrocyte aggregation,
haemoglobin, carboxyhaemoglobin and methaemoglobin concentrations, hematocrit, plasma osmolality and erythrocyte membrane fluidity (fluorescence polarisation probes TMA-DPH and DPH). With ethanol blood concentrations of 45 mM a rise in plasma osmolality (0.352 Osm/kg H2O vs 0.310 Osm/kg H2O; p < 0.001) was verified. With 67 mM concentration a decrease of erythrocyte aggregation (11.03 vs 12.81; p < 0.05) and an increase in plasma osmolality (0.380 Osm/kg H2O vs 0.310 Osm/kg H2O;p < 0.001) were obtained. In conclusion, ethanol only changes erythrocyte aggregation for a concentration of 67 mM. These data could lead to future changes in therapeutic approaches to situations such as alcoholic coma
Superheavy nuclei with the vector self-coupling of the -meson in the relativistic mean-field theory
We have studied properties and shell structure of the superheavy elements
from Z=102 to Z=120 within the framework of the RMF theory. The region of study
spans nuclides with neutron numbers N=150-190. The Lagrangian model NL-SV1 with
the inclusion of the vector self-coupling of the omega-meson has been employed
in this work. We have performed RMF + BCS calculations for an axially deformed
configuration of nuclei. The ground-state binding energies, single-particle
properties and quadrupole deformation of nuclei have been obtained from the
mean-field minimizations. Two-neutron separation energies, values
and alpha-decay half-life have been evaluated. It is shown that a large number
of nuclides exhibit the phenomenon of shape-coexistence over a significant
region of the superheavy elements. Shape coexistence of a prolate and an oblate
shape is prevalent in nuclides far below N=184, whilst nuclei in the vicinity
of N=184 tend to show a shape coexistence between a spherical and an oblate
shape. The shell structure and 2-neutron separation energies obtained with the
RMF theory reinforce the neutron number N=184 as a major magic number. It is
shown that the neutron number N=172 acts akin to a magic number in the deformed
region. It is suggested that the combination Z=120 and N=172 has the potential
of being a doubly magic number in the superheavy region.Comment: 30 pages, 17 figures; Bibliography and citations corrected; To appear
in J. Phys G: Nucl. Part. Phy
Developing a core outcome set (COS) for Dementia with Lewy bodies (DLB) [version 2; peer review: 2 approved, 1 approved with reservations]
\ua9 2023 Grycuk E et al.Background: Dementia with Lewy bodies (DLB) is an important cause of dementia with a range of clinical manifestations, including motor, neuropsychiatric, and autonomic symptoms. Compared with more common forms of dementia such as Alzheimer’s disease, DLB has been the focus of significantly fewer treatment studies, often with diverse outcome measures, making comparison and clinical implementation difficult. A core outcome set (COS) can address this by ensuring that data are comparable, relevant, useful, and usable for making the best healthcare decisions. Methods: Using a multi-stage approach, development of the DLB-COS will include the following stages: (1) A systematic review, following PRISMA guidelines to create an initial long list of outcomes; (2) A two-round online Delphi including clinicians, scientists, policymakers, and individuals with lived experience of DLB and their representatives; (3) An online consensus meeting to agree on the final core list of outcomes (the final DLB-COS) for use in research and clinical practice; (4) A literature search to identify appropriate measurement instruments for the DLB-COS outcomes; (5) A final consensus meeting of the professional stakeholders who attended the online consensus meeting to agree on the instruments that should be used to measure the outcomes in the DLB-COS; and (6) Global dissemination. Discussion: This is a multi-stage project to develop a COS to be used in treatment trials for DLB. A DLB-COS will ensure the selection of relevant outcomes and will identify the instruments to be used to measure DLB globally
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