352 research outputs found
Planck scale inflationary spectra from quantum gravity
We derive the semiclassical evolution of massless minimally coupled scalar
matter in the de Sitter space-time from the Born-Oppenheimer reduction of the
Wheeler-DeWitt equation. We show that the dynamics of trans-Planckian modes can
be cast in the form of an effective modified dispersion relation and that high
energy corrections in the power spectrum of the cosmic microwave background
radiation produced during inflation remain very small if the initial state is
the Bunch-Davies vacuum.Comment: 6 pages, no figures, final version to appear in PR
Fatal poisoning of four workers in a farm: Distribution of hydrogen sulfide and thiosulfate in 10 different biological matrices
We evaluate the distribution of sulfide and thiosulfate (TS) in biological samples of four dairy farmers died inside a pit connected to a manure lagoon. Autopsies were performed 4 days later. Toxicological analyses of sulfide and TS were made using an extractive alkylation technique combined with gas chromatography/mass spectrometry (GC/MS). Autopsies revealed: multiorgan congestion; pulmonary edema; manure inside distal airways of three of the four victims. Sulfide concentrations were cardiac blood: 0.5–3.0 μg/mL, femoral blood: 0.5–1.2 μg/mL, bile: <0.1–2.2 μg/mL; liver 2.8–8.3 μg/g, lung: 5.0–9.4 μg/g, brain: 2.7–13.9 μg/g, spleen: 3.3–6.3 μg/g, fat: <0.1–1.5 μg/g, muscle: 2.6–3.5 μg/g. TS concentrations were cardiac blood: 2.1–4.9 μg/mL, femoral blood: 2.1–2.3 μg/mL, bile: 2.5–4.4 μg/mL, urine: <0.5–1.8 μg/mL; liver <0.5–2.6, lung: 2.8–5.4 μg/g, brain: <0.5–1.9 μg/g, spleen: 1.2–2.9 μg/g, muscle: <0.5–5.6 μg/g. The cause of death was assessed to be acute poisoning by hydrogen sulfide (H2S) for all the victims. Manure inhalation contributed to the death of three subjects. The measurement of sulfide and TS concentrations in biological samples contributed to better understand the sequence of the events. Subjects 3 provided the highest concentration of sulfide in brain, thus, supporting the hypothesis of a rapid loss of consciousness and respiratory depression. One by one, the other farmers entered the pit in attempts to rescue the coworkers but collapsed. Despite the rapid death, subject 3 was the only one with TS detectable in urine. This could be due to differences in metabolism of H2S
Quantum Gravity Effects in Black Holes at the LHC
We study possible back-reaction and quantum gravity effects in the
evaporation of black holes which could be produced at the LHC through a
modification of the Hawking emission. The corrections are phenomenologically
taken into account by employing a modified relation between the black hole mass
and temperature. The usual assumption that black holes explode around TeV
is also released, and the evaporation process is extended to (possibly much)
smaller final masses. We show that these effects could be observable for black
holes produced with a relatively large mass and should therefore be taken into
account when simulating micro-black hole events for the experiments planned at
the LHC.Comment: 14 pages, 8 figures, extended version of hep-ph/0601243 with new
analysis of final products, final version accepted for publication in J.
Phys.
Local representative democracy and protest politics:the case of the Five-star Movement
In recent years, protest politics has become a relevant phenomenon in various European countries. Italy has witnessed the rise of the Five-star Movement (M5S), an anti-establishment party, which, at the 2013 general election, obtained one-fourth of the total votes. However, the story of this ‘party-movement’ started at the local level, as a civic network aimed at changing administrative practices in municipal government. By using an original dataset on representation in 671 Italian municipalities from 2010 to 2014, this article aims to explain not only the subnational political success of the M5S but also the challenges and contradictions that a newly formed movement faces in multi-level electoral arenas
NUTRITIONAL AND DIGESTIVE EFFECTS OF GASTRECTOMY FOR GASTRIC CANCER
Background: Gastrectomy often leads to malnutrition. Objective: The aim of this study was to analyze nutritional and digestive effects of gastrectomy for cancer. Patients and methods: Gastrectomized patients were studied by nutritional assessment including a weekly nutritional diary exploring digestive symptoms. Results: Thirty-two patients were analyzed after a mean follow-up of 41.8 months. The mean percentage of weight loss was 12.9% \ub1 13.5%. After total gastrectomy, mean weight loss was 22% \ub1 1.2%, against 7.4% \ub111.9% for subtotal gastrectomy (p = 0.002). Moreover, advancing age was related to weight loss (p = 0.02), with a peak around 70 years. The most frequent postprandial symptoms were abdominal swelling (62%) and early satiety (59%). Finally, findings of the present study imply that overm a long follow-up, there are no specific intolerances related to gastrectomy. Conclusions: Patients who have undergone a total gastrectomy and elderly gastrectomized patients are at risk of malnutrition and need postoperative nutritional support
Energy-Momentum Tensor of Cosmological Fluctuations during Inflation
We study the renormalized energy-momentum tensor (EMT) of cosmological scalar
fluctuations during the slow-rollover regime for chaotic inflation with a
quadratic potential and find that it is characterized by a negative energy
density which grows during slow-rollover. We also approach the back-reaction
problem as a second-order calculation in perturbation theory finding no
evidence that the back-reaction of cosmological fluctuations is a gauge
artifact. In agreement with the results on the EMT, the average expansion rate
is decreased by the back-reaction of cosmological fluctuations.Comment: 19 pages, no figures.An appendix and references added, conclusions
unchanged, version accepted for publication in PR
Italian politics in an era of recession : the end of bipolarism?
Italian politics have undergone momentous change in the 2007–2017 decade under the impact of the eurozone crisis, whose peak in 2011–2013 could be equated to the earlier watershed years of 1992–1994. The lasting impact of the upheaval in Italian politics in the early 1990s could still be felt in the decade of economic recession, but there were also new challenges prompted by a crisis that had its roots in international financial contagion and which unravelled under the shadow of both recession and austerity. The changes were of an economic, social, cultural, institutional, policy-oriented and political nature. If one central quintessentially political theme stands out by the end of this decade it is the apparent exhaustion of the quest for bipolarisation that was initiated in the early 1990s
Constraints from Solar and Reactor Neutrinos on Unparticle Long-Range Forces
We have investigated the impact of long-range forces induced by unparticle
operators of scalar, vector and tensor nature coupled to fermions in the
interpretation of solar neutrinos and KamLAND data. If the unparticle couplings
to the neutrinos are mildly non-universal, such long-range forces will not
factorize out in the neutrino flavour evolution. As a consequence large
deviations from the observed standard matter-induced oscillation pattern for
solar neutrinos would be generated. In this case, severe limits can be set on
the infrared fix point scale, Lambda_u, and the new physics scale, M, as a
function of the ultraviolet (d_UV) and anomalous (d) dimension of the
unparticle operator. For a scalar unparticle, for instance, assuming the
non-universality of the lepton couplings to unparticles to be of the order of a
few per mil we find that, for d_UV=3 and d=1.1, M is constrained to be M >
O(10^9) TeV (M > O(10^10) TeV) if Lambda_u= 1 TeV (10 TeV). For given values of
Lambda_u and d, the corresponding bounds on M for vector [tensor] unparticles
are approximately 100 [3/Sqrt(Lambda_u/TeV)] times those for the scalar case.
Conversely, these results can be translated into severe constraints on
universality violation of the fermion couplings to unparticle operators with
scales which can be accessible at future colliders.Comment: 13 pages, 3 figures. Minor changes due to precision in numerical
factors and correction in figure labels. References added. Conclusions remain
unchange
Constraints on Astro-unparticle Physics from SN 1987A
SN 1987A observations have been used to place constraints on the interactions
between standard model particles and unparticles. In this study we calculate
the energy loss from the supernovae core through scalar, pseudo scalar, vector,
pseudo vector unparticle emission from nuclear bremsstrahlung for degenerate
nuclear matter interacting through one pion exchange. In order to examine the
constraints on we considered the emission of scalar, pseudo
scalar, vector, pseudo vector and tensor through the pair annihilation process
. In addition we have re-examined other pair
annihilation processes. The most stringent bounds on the dimensionless coupling
constants for and are obtained from
nuclear bremsstrahlung process for the pseudo scalar and pseudo-vector
couplings and for
tensor interaction, the best limit on dimensionless coupling is obtained from
and we get .Comment: 12 pages, 2 postscript figure
Gamma-ray flaring activity from the gravitationally lensed blazar PKS 1830-211 observed by Fermi LAT
The Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope
routinely detects the highly dust-absorbed, reddened, and MeV-peaked flat
spectrum radio quasar PKS 1830-211 (z=2.507). Its apparent isotropic gamma-ray
luminosity (E>100 MeV) averaged over 3 years of observations and peaking
on 2010 October 14/15 at 2.9 X 10^{50} erg s^{-1}, makes it among the brightest
high-redshift Fermi blazars. No published model with a single lens can account
for all of the observed characteristics of this complex system. Based on radio
observations, one expects time delayed variability to follow about 25 days
after a primary flare, with flux about a factor 1.5 less. Two large gamma-ray
flares of PKS 1830-211 have been detected by the LAT in the considered period
and no substantial evidence for such a delayed activity was found. This allows
us to place a lower limit of about 6 on the gamma rays flux ratio between the
two lensed images. Swift XRT observations from a dedicated Target of
Opportunity program indicate a hard spectrum and with no significant
correlation of X-ray flux with the gamma-ray variability. The spectral energy
distribution can be modeled with inverse Compton scattering of thermal photons
from the dusty torus. The implications of the LAT data in terms of variability,
the lack of evident delayed flare events, and different radio and gamma-ray
flux ratios are discussed. Microlensing effects, absorption, size and location
of the emitting regions, the complex mass distribution of the system, an
energy-dependent inner structure of the source, and flux suppression by the
lens galaxy for one image path may be considered as hypotheses for
understanding our results.Comment: 14 pages, 6 figures, 2 tables. Accepted by the The Astrophysical
Journal. Corresponding authors: S. Ciprini (ASI ASDC & INAF OAR, Rome,
Italy), S. Buson (INAF Padova & Univ. of Padova, Padova, Italy), J. Finke
(NRL, Washington, DC, USA), F. D'Ammando (INAF IRA, Bologna, Italy
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