977 research outputs found
Consequences of f(R)-theories of gravity on gravitational leptogenesis
f(R)-theories of gravity are reviewed in the framework of the
matter-antimatter asymmetry in the Universe. The asymmetry is generated by the
gravitational coupling of heavy (Majorana) neutrinos with the Ricci scalar
curvature. In order that the mechanism works, a time varying non-zero Ricci
curvature is necessary. The latter is provided by f(R) cosmology, whose
Lagrangian density is of the form {\cal L}(R)\sim f(R). In particular we study
the cases f(R)\sim R+\alpha R^n and f(R)\sim R^{1+\epsilon}.Comment: 14 page
Cosmological evolution of thermal relic particles in gravity
By considering gravity models, the cosmic evolution is modified with
respect to the standard CDM scenario. In particular, the thermal
history of particles results modified. In this paper, we derive the evolution
of relics particles (WIMPs) assuming a reliable cosmological solution
and taking into account observational constraints. The connection to the PAMELA
experiment is also discussed. Results are consistent with constraints coming
from BICEP2 and PLANCK experiments.Comment: 8 pages, 4 figure
A combined approach to assess the potential coverage of a multicomponent protein-based vaccine
Meningococcal disease caused by Neisseria meningitidis sero- group B is a public health concern even in developed countries. Despite glycoconjugate vaccines against the other invasive sero- groups (A, C, W135, Y) are already available and successfully introduced in many countries, no vaccine is currently in use for prevention of serogroup B meningitis.
A protein based, multicomponent vaccine (4CMenB) has been developed and proposed for prevention of invasive serogroup B meningococcal disease (MenB). This novel vaccine has been tested in clinical trials and shown to be well tolerated and immunogenic, inducing bactericidal antibodies in infants, adolescents and adults. The high level of genetic and antigenic variability observed in MenB clinical isolates, requires a suitable method to assess the ability of the 4CMenB vaccine to cover genetically diverse menig- ococcal strains and to estimate the potential public health impact. To this purpose the Meningococcal Antigen Typing System (MATS) has been developed and recently described. This method provides a quick and reproducible tool to estimate the level of expression and immunoreactivity of each of the vaccine antigens, in any meningococcal isolate, and it is related to the likelihood that the isolate will be killed by sera from immunized subjects.
A multi-laboratory study involving several European countries, demonstrates that the 4CMenB has the potential to protect against a significant proportion of menB strains circulating in Europe.
The full article is free available on www.jpmh.or
Three-dimensional simulations of premixed hydrogen/air flames in microtubes
The dynamics of fuel-lean (equivalence ratio φ = 0.5) premixed hydrogen/air atmospheric pressure flames are investigated in open cylindrical tubes with diameters of d = 1.0 and 1.5 mm using three-dimensional numerical simulations with detailed chemistry and transport. In both cases, the inflow velocity is varied over the range where the flames can be stabilized inside the computational domain. Three axisymmetric combustion modes are observed in the narrow tube: steady mild combustion, oscillatory ignition/extinction and steady flames as the inflow velocity is varied in the range 0.5 ≤ UIN ≤ 500 cm s−1. In the wider tube, richer flame dynamics are observed in the form of steady mild combustion, oscillatory ignition/extinction, steady closed and open axisymmetric flames, steady non-axisymmetric flames and azimuthally spinning flames (0.5 ≤ UIN ≤ 600 cm s−1). Coexistence of the spinning and the axisymmetric modes is obtained over relatively wide ranges of UIN. Axisymmetric simulations are also performed in order to better understand the nature of the observed transitions in the wider tube. Fourier analysis during the transitions from the steady axisymmetric to the three-dimensional spinning mode and to the steady non-axisymmetric modes reveals that the m = 1 azimuthal mode plays a dominant role in the transition
Autism Spectrum Disorder and Narcolepsy: A Possible Connection That Deserves to Be Investigated.
Narcolepsy in childhood-adolescence is characterized by a high occurrence of
psychiatric comorbidities. The most frequent psychiatric disorders reported in
these patients are attention deficit/hyperactivity disorder, depression, anxiety
disorder, and schizophrenia. However, narcolepsy can be associated also with
introversion, sorrowfulness, feelings of inferiority, impaired affectivity
modulation, emotional lability, irritability, aggressiveness, and poor attention,
that have been pooled by some authors under a definition of "narcoleptic
personality." Some aspects of this "narcoleptic personality," and in particular
introversion, impaired affectivity modulation, irritability, and poor attention,
partially overlap with the clinical features of the individuals with autism
spectrum disorder, considering also those that are not regarded as core autism
symptoms. Till now, in literature the number of cases affected by both narcolepsy
and autism spectrum disorder (seven patients) has been clearly too small to
demonstrate the presence of a pathogenetic link between these two conditions, but
this possible connection has not yet been adequately investigated, despite the
presence of several points in common. The finding of a connection between
narcolepsy and autism spectrum disorder could boost the study of possible
etiopathogenetic mechanisms shared between these two apparently so distant
disorders. Basing on the literature data summarized in this paper, in the
diagnostic work-up of a child with narcolepsy it is essential to evaluate also
the social-communicative behavior using standardized tools in order to detect the
real recurrence of clinical features suggesting an autism spectrum disorder. At
the same time, it appears necessary to screen in the individuals with autism
spectrum disorder for the possible presence of evoking symptoms of narcolepsy
Esperienza dell'attesa e retoriche del tempo. L’impegno dell’antropologia nel campo sanitario
Sleep disturbances and sleep disorders as risk factors for chronic postsurgical pain: A systematic review and meta-analysis
This systematic review and meta-analysis aimed at evaluating the role of sleep disturbances and sleep disorders in influencing presence and intensity of chronic postsurgical pain (CPSP). We included cohort studies which enrolled adults, assessed sleep disturbances or disorders before surgery, measured pain intensity, presence of pain, or opioid use at least three months after surgery. Eighteen studies were included in a narrative synthesis and 12 in a meta-analysis. Sleep disturbances and disorders were significantly related to CPSP, with a small effect size, r = 0.13 (95% CI 0.06–0.20). The certainty of evidence was rated low due to risk of bias and heterogeneity. In subgroup analyses the above association was significant in studies that used pain intensity as the outcome, but not in those that used presence of pain; in studies on patients who underwent total knee arthroplasty or other surgeries, but not in those on patients who had breast cancer surgery or total hip arthroplasty; in the single study that assessed insomnia and in studies that assessed sleep disturbances as predictors. A meta-regression showed that the follow-up length was positively associated with the overall estimate. Our findings suggest that presurgical sleep disturbances and disorders should be evaluated to detect patients at risk for CPSP. Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=27265
Early versus late tracheostomy in pediatric intensive care unit: does it matter? A 6-year experience
CHARACTERIZATION OF EXTRACTIVE WASTE FACILITIES FOR SRM RECOVERY FROM MINING SITES: CASE STUDIES FROM THE SMART GROUND PROJECT
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