847 research outputs found
A closer look at string resonances in dijet events at the LHC
The first string excited state can be observed as a resonance in dijet
invariant mass distributions at the LHC, if the scenario of low-scale string
with large extra dimensions is realized. A distinguished property of the dijet
resonance by string excited states from that the other "new physics" is that
many almost degenerate states with various spin compose a single resonance
structure. It is examined that how we can obtain evidences of low-scale string
models through the analysis of angular distributions of dijet events at the
LHC. Some string resonance states of color singlet can obtain large mass shifts
through the open string one-loop effect, or through the mixing with closed
string states, and the shape of resonance structure can be distorted. Although
the distortion is not very large (10% for the mass squared), it might be able
to observe the effect at the LHC, if gluon jets and quark jets could be
distinguished in a certain level of efficiency.Comment: 12 pages, 8 figure
Lifetime determination of excited states in Cd-106
Two separate experiments using the Differential Decay Curve Method have been performed to extract mean lifetimes of excited states in 106 Cd. The inedium-spin states of interest were populated by the Mo-98(C-12, 4n) Cd-106 reaction performed at the Wright Nuclear Structure Lab., Yale University. From this experiment, two isomeric state mean lifetimes have been deduced. The low-lying states were populated by the Mo-96(C-13, 3n)Cd-106 reaction performed at the Institut fur Kernphysik, Universitat zu Koln. The mean lifetime of the I-pi = 2(1)(+) state was deduced, tentatively, as 16.4(9) ps. This value differs from the previously accepted literature value from Coulomb excitation of 10.43(9) ps
Colliding Hadrons as Cosmic Membranes and Possible Signatures of Lost Momentum
We argue that in the TeV-gravity scenario high energy hadrons colliding on
the 3-brane embedded in D=4+n-dimensional spacetime, with n dimensions smaller
than the hadron size, can be considered as cosmic membranes. In the
5-dimensional case these cosmic membranes produce effects similar to cosmic
strings in the 4-dimensional world. We calculate the corrections to the eikonal
approximation for the gravitational scattering of partons due to the presence
of effective hadron cosmic membranes. Cosmic membranes dominate the momentum
lost in the longitudinal direction for colliding particles that opens new
channels for particle decays.Comment: 15 pages, Late
Predictive Models for the Diagnostic of Human Visceral Leishmaniasis in Brazil
Visceral leishmaniasis (VL) is a neglected tropical disease endemic to 65 countries, including Brazil, where the disease frequently occurs in remote locations and treatment is often performed on the basis of clinical suspicion. Predictive models based on scoring systems could be a helpful tool for the clinical management of VL. Based on clinical signs and symptoms, and five different serological tests of 213 patients with parasitologically confirmed (cases) and 119 with clinical suspicion of VL but with another confirmed etiology (non-cases), twelve prediction models using logistic regression and classification and regression trees (CART) for VL diagnosis were developed. The model composed of the clinical-laboratory variables and the rk39 rapid test showed the best performance in both logistic regression and CART (Sensitivity of 90.1% and specificity ranging from 97.2–97.4%). The scoring system is simple and based on the clinical-laboratory findings that are easily available in most clinical settings. The results suggest that those models might be useful in locations where access to available diagnostic methods is difficult, contributing to more efficient and more rational allocation of healthcare resources
Arsenic exposure and outcomes of antimonial treatment in visceral leishmaniasis patients in bihar, India:a retrospective cohort study
Funding: This work was supported by a Clinical PhD Fellowship to MRP (090665) and a Principal Research Fellowship to AHF (079838) from the Wellcome Trust (http://www.wellcome.ac.uk). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
Use of liothyronine (T3) in hypothyroidism: Joint British Thyroid Association/Society for endocrinology consensus statement
\ua9 2023 The Authors. Clinical Endocrinology published by John Wiley & Sons Ltd.Persistent symptoms in patients treated for hypothyroidism are common. Despite more than 20 years of debate, the use of liothyronine for this indication remains controversial, as numerous randomised trials have failed to show a benefit of treatment regimens that combine liothyronine (T3) with levothyroxine over levothyroxine monotherapy. This consensus statement attempts to provide practical guidance to clinicians faced with patients who have persistent symptoms during thyroid hormone replacement therapy. It applies to non-pregnant adults and is focussed on care delivered within the UK National Health Service, although it may be relevant in other healthcare environments. The statement emphasises several key clinical practice points for patients dissatisfied with treatment for hypothyroidism. Firstly, it is important to establish a diagnosis of overt hypothyroidism; patients with persistent symptoms during thyroid hormone replacement but with no clear biochemical evidence of overt hypothyroidism should first have a trial without thyroid hormone replacement. In those with established overt hypothyroidism, levothyroxine doses should be optimised aiming for a TSH in the 0.3–2.0 mU/L range for 3 to 6 months before a therapeutic response can be assessed. In some patients, it may be acceptable to have serum TSH below reference range (e.g. 0.1–0.3 mU/L), but not fully suppressed in the long term. We suggest that for some patients with confirmed overt hypothyroidism and persistent symptoms who have had adequate treatment with levothyroxine and in whom other comorbidities have been excluded, a trial of liothyronine/levothyroxine combined therapy may be warranted. The decision to start treatment with liothyronine should be a shared decision between patient and clinician. However, individual clinicians should not feel obliged to start liothyronine or to continue liothyronine medication provided by other health care practitioners or accessed without medical advice, if they judge this not to be in the patient\u27s best interest
Signatures of low-scale string models at the LHC
Low-scale string models, in which the string scale M_s is of the order of TeV
with large extra dimensions, can solve the problems of scale hierarchy and
non-renormalizable quantum gravity in the standard model. String excited states
of the standard model particles are possibly observed as resonances in the
dijet invariant mass distribution at the LHC. There are two properties to
distinguish whether the resonances are due to low-scale string or some other
"new physics". One is a characteristic angular distribution in dijet events at
the resonance due to spin degeneracy of string excited states, and the other is
an appearance of the second resonance at a characteristic mass of second string
excited states. We investigate a possibility to observe these evidences of
low-scale string models by Monte Carlo simulations with a reference value of
M_s = 4 TeV at sqrt{s} = 14 TeV. It is shown that spin degeneracy at the dijet
resonance can be observed by looking the chi-distribution with integrated
luminosity of 20 fb^-1. It is shown that the second resonance can be observed
at rather close to the first resonance in the dijet invariant mass distribution
with integrated luminosity of 50 fb^-1. These are inevitable signatures of
low-scale string models.Comment: 21 pages, 8 figure
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