318 research outputs found
General massive one-loop off-shell three-point functions
In this work we compute the most general massive one-loop off-shell
three-point vertex in D-dimensions, where the masses, external momenta, and
exponents of propagators are arbitrary. This follows our previous paper in
which we have calculated several new hypergeometric series representations for
massless and massive (with equal masses) scalar one-loop three-point functions,
in the negative dimensional approach.Comment: 16 pages, 2 figures, 4 table
Image-guided multisession radiosurgery of skull base meningiomas
Background: The efficacy of single-session stereotactic radiosurgery (sSRS) for the treatment of intracranial meningioma is widely recognized. However, sSRS is not always feasible in cases of large tumors and those lying close to critically radiation-sensitive structures. When surgery is not recommended, multi-session stereotactic radiosurgery (mSRS) can be applied. Even so, the efficacy and best treatment schedule of mSRS are not yet established. The aim of this study is to validate the role of mSRS in the treatment of skull base meningiomas. Methods: A retrospective analysis of patients with skull base meningiomas treated with mSRS (two to five fractions) at the University of Messina, Italy, from 2008 to 2018, was conducted. Results: 156 patients met the inclusion criteria. The median follow-up period was 36.2 \ub1 29.3 months. Progression-free survival at 2-, 5-, and 10-years was 95%, 90%, and 80.8%, respectively. There were no new visual or motor deficits, nor cranial nerves impairments, excluding trigeminal neuralgia, which was reported by 5.7% of patients. One patient reported carotid occlusion and one developed brain edema. Conclusion: Multisession radiosurgery is an effective approach for skull base meningiomas. The long-term control is comparable to that obtained with conventionally-fractionated radiotherapy, while the toxicity rate is very limited
Electromagnetic Form Factors of a Massive Neutrino
Electromagnetic form factors of a massive neutrino are studied in a minimally
extended standard model in an arbitrary gauge and taking into account
the dependence on the masses of all interacting particles. The contribution
from all Feynman diagrams to the charge, magnetic, and anapole form factors, in
which the dependence on the masses of all particles as well as on gauge
parameters is accounted for exactly, are obtained for the first time in
explicit form. The asymptotic behavior of the magnetic form factor for large
negative squares of the momentum of an external photon is analyzed and
expression for the anapole moment of a massive neutrino is derived. The results
are generalized to the case of mixing between various generations of the
neutrino. Explicit expressions are obtained for the charge, magnetic, and
electric dipole and anapole transition form factors as well as for the
transition electric dipole moment.Comment: 16 pares with 5 figures in pdf forma
Prevalence and management of pain in Italian patients with advanced non-small-cell lung cancer
Pain is a highly distressing symptom for patients with advanced cancer. WHO
analgesic ladder is widely accepted as a guideline for its treatment. Our aim was
to describe pain prevalence among patients diagnosed with advanced non-small-cell
lung cancer (NSCLC), impact of pain on quality of life (QoL) and adequacy of pain
management. Data of 1021 Italian patients enrolled in three randomised trials of
chemotherapy for NSCLC were pooled. QoL was assessed by EORTC QLQ-C30 and LC-13.
Analgesic consumption during the 3 weeks following QoL assessment was recorded.
Adequacy of pain management was evaluated by the Pain Management Index (PMI).
Some pain was reported by 74% of patients (42% mild, 24% moderate and 7% severe);
50% stated pain was affecting daily activities (30% a little, 16% quite a bit, 3%
very much). Bone metastases strongly affected presence of pain. Mean global QoL
linearly decreased from 64.9 to 36.4 from patients without pain to those with
severe pain (P<0.001). According to PMI, 616 out of 752 patients reporting pain
(82%) received inadequate analgesic treatment. Bone metastases were associated
with improved adequacy and worst pain with reduced adequacy at multivariate
analysis. In conclusion, pain is common in patients with advanced NSCLC,
significantly affects QoL, and is frequently undertreated. We recommend that:
(i). pain self-assessment should be part of oncological clinical practice; (ii).
pain control should be a primary goal in clinical practice and in clinical
trials; (iii). physicians should receive more training in pain management; (iv).
analgesic treatment deserves greater attention in protocols of anticancer
treatment
Using an Observational Framework to investigate adult language input to young children in a naturalistic environment
The correlation between the communicative intent of parents, in terms of their expectation of a response and the response patterns of young children aged 23â25 months during parentâchild interactions, was investigated. An Observational Framework was used to code these parameters in interactions between 36 children and their mothers. The children were assigned by cluster analysis to `advanced', `typical' and `delayed' language groups and their responses were coded with respect to the degree of correctness or appropriateness within the interaction. Differences in both the parental response expectations and the children's response patterns across the three clusters are discussed
Hydrodynamics of galactic dark matter
We consider simple hydrodynamical models of galactic dark matter in which the
galactic halo is a self-gravitating and self-interacting gas that dominates the
dynamics of the galaxy. Modeling this halo as a sphericaly symmetric and static
perfect fluid satisfying the field equations of General Relativity, visible
barionic matter can be treated as ``test particles'' in the geometry of this
field. We show that the assumption of an empirical ``universal rotation curve''
that fits a wide variety of galaxies is compatible, under suitable
approximations, with state variables characteristic of a non-relativistic
Maxwell-Boltzmann gas that becomes an isothermal sphere in the Newtonian limit.
Consistency criteria lead to a minimal bound for particle masses in the range
and to a constraint between the central
temperature and the particles mass. The allowed mass range includes popular
supersymmetric particle candidates, such as the neutralino, axino and
gravitino, as well as lighter particles ( keV) proposed by numerical
N-body simulations associated with self-interactive CDM and WDM structure
formation theories.Comment: LaTeX article style, 16 pages including three figures. Final version
to appear in Classical and Quantum Gravit
Cisplatin-based first-line treatment of elderly patients with advanced non-small-cell lung cancer: Joint analysis of MILES-3 and MILES-4 phase III trials
Purpose: To test the efficacy of adding cisplatin to first-line treatment for elderly patients with advanced non-small-cell lung cancer (NSCLC) within a combined analysis of two parallel phase III trials, MILES-3 and MILES-4. Patients and Methods: Patients with advanced NSCLC who were older than age 70 years with Eastern Cooperative Oncology Group performance status 0 to 1 were randomly assigned to gemcitabine or pemetrexed, without or with cisplatin. In each trial, 382 events were required to detect a hazard ratio (HR) of death of 0.75, with 80% power and two-tailed a of .05. Trials were closed prematurely because of slow accrual, but the joint database allowed us to analyze the efficacy of cisplatin on the basis of intention-to-treat and adjusted by trial, histotype, non-platinum companion drug, stage, performance status, sex, age, and size of the study center. Results: From March 2011 to August 2016, 531 patients (MILES-3, 299; MILES-4, 232) were assigned to gemcitabine or pemetrexed without (n = 268) or with cisplatin (n = 263). Median age was 75 years, 79% were male, and 70% had nonsquamous histology. At a median 2-year follow-up, 384 deaths and 448 progression-free survival events were recorded. Overall survival was not significantly prolonged with cisplatin (HR, 0.86; 95% CI, 0.70 to 1.05; P = .14) and global health status score of quality of life was not improved, whereas progression-free survival (HR, 0.76; 95% CI, 0.63 to 0.92; P = .005) and objective response rate (15.5% v 8.5%; P = .02) were significantly better. Significantly more severe hematologic toxicity, fatigue, and anorexia were found with cisplatin. Conclusion: The addition of cisplatin to single-agent chemotherapy does not significantly prolong overall survival, and it does not improve global health status score of quality of life in elderly patients with advanced NSCLC
Beyond series expansions: mathematical structures for the susceptibility of the square lattice Ising model
We first study the properties of the Fuchsian ordinary differential equations
for the three and four-particle contributions and
of the square lattice Ising model susceptibility. An analysis of some
mathematical properties of these Fuchsian differential equations is sketched.
For instance, we study the factorization properties of the corresponding linear
differential operators, and consider the singularities of the three and
four-particle contributions and , versus the
singularities of the associated Fuchsian ordinary differential equations, which
actually exhibit new ``Landau-like'' singularities. We sketch the analysis of
the corresponding differential Galois groups. In particular we provide a
simple, but efficient, method to calculate the so-called ``connection
matrices'' (between two neighboring singularities) and deduce the singular
behaviors of and . We provide a set of comments and
speculations on the Fuchsian ordinary differential equations associated with
the -particle contributions and address the problem of the
apparent discrepancy between such a holonomic approach and some scaling results
deduced from a Painlev\'e oriented approach.Comment: 21 pages Proceedings of the Counting Complexity conferenc
Measurement of the neutron capture cross section of the s-only isotope 204Pb from 1 eV to 440 keV
The neutron capture cross section of 204Pb has been measured at the CERN
n_TOF installation with high resolution in the energy range from 1 eV to 440
keV. An R-matrix analysis of the resolved resonance region, between 1 eV and
100 keV, was carried out using the SAMMY code. In the interval between 100 keV
and 440 keV we report the average capture cross section. The background in the
entire neutron energy range could be reliably determined from the measurement
of a 208Pb sample. Other systematic effects in this measurement could be
investigated and precisely corrected by means of detailed Monte Carlo
simulations. We obtain a Maxwellian average capture cross section for 204Pb at
kT=30 keV of 79(3) mb, in agreement with previous experiments. However our
cross section at kT=5 keV is about 35% larger than the values reported so far.
The implications of the new cross section for the s-process abundance
contributions in the Pb/Bi region are discussed.Comment: 8 pages, 3 figures, article submitted to Phys. Rev.
Finding new relationships between hypergeometric functions by evaluating Feynman integrals
Several new relationships between hypergeometric functions are found by
comparing results for Feynman integrals calculated using different methods. A
new expression for the one-loop propagator-type integral with arbitrary masses
and arbitrary powers of propagators is derived in terms of only one Appell
hypergeometric function F_1. From the comparison of this expression with a
previously known one, a new relation between the Appell functions F_1 and F_4
is found. By comparing this new expression for the case of equal masses with
another known result, a new formula for reducing the F_1 function with
particular arguments to the hypergeometric function _3F_2 is derived. By
comparing results for a particular one-loop vertex integral obtained using
different methods, a new relationship between F_1 functions corresponding to a
quadratic transformation of the arguments is established. Another reduction
formula for the F_1 function is found by analysing the imaginary part of the
two-loop self-energy integral on the cut. An explicit formula relating the F_1
function and the Gaussian hypergeometric function _2F_1 whose argument is the
ratio of polynomials of degree six is presented.Comment: 14 pages, 3 figure
- âŠ