781 research outputs found
DAMA detection claim is still compatible with all other DM searches
We show that the annual modulation signal observed by DAMA can be reconciled
with all other negative results from dark matter searches with a conventional
halo model for particle masses around 5 to 9 GeV. We also show which particular
dark matter stream could produce the DAMA signal.Comment: Talk given at TAUP2005, Sept. 10-14 2005, Zaragoza (Spain). 3 pages,
4 figure
Measuring the prompt atmospheric neutrino flux with down-going muons in neutrino telescopes
In the TeV energy region and above, the uncertainty in the level of prompt
atmospheric neutrinos would limit the search for diffuse astrophysical
neutrinos. We suggest that neutrino telescopes may provide an empirical
determination of the flux of prompt atmospheric electron and muon neutrinos by
measuring the flux of prompt down-going muons. Our suggestion is based on the
consideration that prompt neutrino and prompt muon fluxes at sea level are
almost identical.Comment: 4 pages, 3 figure
Super-Kamiokande 0.07 eV Neutrinos in Cosmology: Hot Dark Matter and the Highest Energy Cosmic Rays
Relic neutrinos with mass in the range indicated by Super-Kamiokande results
if neutrino masses are hierarchial (about 0.07 eV) are many times deemed too
light to be cosmologically relevant. Here we remark that these neutrinos may
significantly contribute to the dark matter of the Universe (with a large
lepton asymmetry ) and that their existence might be revealed by the
spectrum of ultra high energy cosmic rays (maybe even in the absence of a large
).Comment: Talk given at the ``4th International Symposium on Sources and
Detection of Dark Matter in the Universe", February 23-25, 2000, Marina del
Rey, CA (to appear in its proceedings) and at the ``Cosmic Genesis and
Fundamental Physics" workshop, October 28-30, 1999, Sonoma State University,
Santa Rosa, CA. (8 p. 1 fig.
A narrative review about difficult laparoscopic cholecystectomy: technical tips
Background: Laparoscopic cholecystectomy (LC) is the most practiced procedure in general surgery worldwide. It is nowadays the optimum surgical procedure for symptomatic gallbladder lithiasis. Nevertheless, it should not be underestimated since vascular and biliary duct injuries are not uncommon, with devastating consequences. This study aimed to advise the best surgical technical approach for LC according to the intraoperative situation to avoid accidental anatomical structures injuries. Methods: A traditional narrative literature search for articles published up to December 2021 was performed using the most common search engines (PubMed, Web of Science, Google Scholar). The search strategy utilized in all databases included the combination of the keywords: "laparoscopic cholecystectomy", "difficult cholecystectomy", "acute cholecystitis", "prevention bile duct injuries", "safe cholecystectomy". No restrictions were applied to the language of the publication if an English version of the article was available. Key Content and Findings: Difficult laparoscopic cholecystectomy (DLC) is a distressing condition. Its definition is not well established and may vary according to the surgeon's experience. Several techniques have been proposed to minimize the bile duct or hepatic injury risk during the challenging cholecystectomy. Conclusions: Although LC is nowadays the optimum surgical procedure for symptomatic gallbladder lithiasis, it should not be underestimated since vascular and biliary duct injuries are very morbid, significantly increase care costs, and often lead to litigations
Anisotropy of the Cosmic Neutrino Background
The cosmic neutrino background (CNB) consists of low-energy relic neutrinos
which decoupled from the cosmological fluid at a redshift z ~ 10^{10}. Despite
being the second-most abundant particles in the universe, direct observation
remains a distant challenge. Based on the measured neutrino mass differences,
one species of neutrinos may still be relativistic with a thermal distribution
characterized by the temperature T ~ 1.9K. We show that the temperature
distribution on the sky is anisotropic, much like the photon background,
experiencing Sachs-Wolfe and integrated Sachs-Wolfe effects.Comment: 5 pages, 2 figures / updated references, discussion of earlier wor
Aspirin Use in Patients Undergoing Preoperative Evaluation for Minor Surgery
We found that 505 patients were treated with aspirin (16.8%), 312 men (61.8%) and 193 women (38.2%) (P < .05). In the group of patients treated with aspirin we found that 379 subjects—254 men (67%) and 125 women (33%)—were treated with aspirin according to guidelines for prevention of cardiovascular disease. In addition, 32 patients (all men) were treated with aspirin outside of guideline indications. Seven hundred ninety-eight patients (26.6%) that needed aspirin or antiplatelet therapy due to their cardiovascular risk were not treated, despite having no contraindication or allergy, and 126 patients discontinued aspirin despite appropriate indication
Dome Down Laparoscopic Cholecystectomy: Our Experience and the State of Art
Introduction: Laparoscopic Cholecystectomy is nowadays the gold standard technique for
benign gallbladder disease both in elective and emergency surgery. But it is even true that in very
acute cholecystitis when the tissues are inflamed and the anatomy can be difficult to recognize, the
classic laparoscopic approach can lead to biliary and vascular injuries. Dome down laparoscopic
approach can be used to avoid conversion to open surgery and decrease surgical complications.
Methods: A retrospective record of all Cholecystectomy carried out in our unit by experienced
surgeons from January 2013 to August 2017 was examined. Cases were divided by surgical
technique: Classical laparoscopic technique, Open cholecystectomy, Laparoscopic converted to
open cholecystectomy, Dome down laparoscopic Cholecystectomy (DDLC). A systematic literature
search was performed using PubMedz and Embase databases. The search was limited to studies
on humans and to those reported in the English language between January 2009 and December
2016.
Results and discussion: 194 cholecystectomy were performed, among these 163 with
laparoscopic technique and 3% of all laparoscopic approached cholecystectomy were performed
as DDLC. The mean hospital stay was 5 days (2-11). 1 out of 5 patients needed postoperatory
ERCP and endobiliary stent was positioned removed in 30 days with no other complications.
Other 4 patients were evaluated after 1 week from dismission with no evidence of postoperative
complications.
Conclusion: Dome down cholecystectomy is a feasible and safe procedure; it avoids biliary
and vascular injuries in difficult cholecystectomy. It can still be improved by the combination
with ultrasonic devices or with new surgical techniques such as Single-incision Laparoscopic
cholecistectomy
On the measurement of the proton-air cross section using longitudinal shower profiles
In this paper, we will discuss the prospects of deducing the proton-air cross
section from fluorescence telescope measurements of extensive air showers. As
it is not possible to observe the point of first interaction
directly, other observables closely linked to must be inferred from
the longitudinal profiles. This introduces a dependence on the models used to
describe the shower development. The most straightforward candidate for a good
correlation to is the depth of shower maximum . We
will discuss the sensitivity of an -based analysis on and quantify the systematic uncertainties arising from the model
dependence, parameters of the reconstruction method itself and a possible
non-proton contamination of the selected shower sample.Comment: 4 pages, Proceedings for ISVHECRI Weihei 200
Associated single photons and doubly charged scalar at linear e-e- colliders
Doubly charged scalars, predicted in many models having exotic Higgs
representations, can in general have lepton-number violating (LFV) couplings.
We show that by using an associated monoenergetic final state photon seen at a
future linear e-e- collider, we can have a clear and distinct signature for a
doubly-charged resonance. The strength of the Delta L=2 coupling can also be
probed quite effectively as a function of the recoil mass of the doubly-charged
scalar.Comment: Reference adde
Anomaly mediated SUSY breaking scenarios in the light of cosmology and in the dark (matter)
Anomaly mediation is a popular and well motivated supersymmetry breaking
scenario. Different possible detailed realisations of this set-up are studied
and actively searched for at colliders. Apart from limits coming from flavour,
low energy physics and direct collider searches, these models are usually
constrained by the requirement of reproducing the observations on dark matter
density in the universe. We reanalyse these bounds and in particular we focus
on the dark matter bounds both considering the standard cosmological model and
alternative cosmological scenarios. These scenarios do not change the
observable cosmology but relic dark matter density bounds strongly depend on
them. We consider few benchmark points excluded by standard cosmology dark
matter bounds and suggest that loosening the dark matter constraints is
necessary in order to avoid a too strong (cosmological) model dependence in the
limits that are obtained for these models. We also discuss briefly the
implications for phenomenology and in particular at the Large Hadron Collider.Comment: 37 pages, 20 figures, 1 tabl
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