4,175 research outputs found
Subtotal pancreatectomy for cancer: closure of the pancreatic remnant with staplers
This paper presents a 2-year series of 26 consecutive pancreatectomies for periampullary cancer where the pancreatic tail was closed with a stapler in order to avoid complications related to a pancreatico-digestive anastomosis. The follow-up period was 14 months or more. Seven patients developed operative complications. Pancreatic fistulas developed in 3 patients. The fistulas closed spontaneously in 2 of the patients after 2-4 months. Intraabdominal abscesses developed in 4 patients and required surgical drainage. In 1 of these patients, the abscess eroded a large vessel with a fatal outcome resulting in an operative mortality rate of 3.8%. A transient postoperative gastric stasis was observed in seven patients. Postoperative hospital median stay was 27 days (range 10-83 days). Eighteen patients have died after 4-30 months in recurrent disease and seven patients are alive after a follow-up period of 15-29 months. Pancreatic endocrine function seemed well preserved; diabetes mellitus has developed in only one patient. In conclusion, it appears that subtotal pancreatectomy with closure of the pancreatic remnant with staples gives a low morbidity and mortality. Although the conclusion should be tempered by the small number of patients, the results justify continued evaluation of this technique with long-term follow-up
Photon creation from vacuum and interactions engineering in nonstationary circuit QED
We study theoretically the nonstationary circuit QED system in which the
artificial atom transition frequency, or the atom-cavity coupling, have a small
periodic time modulation, prescribed externally. The system formed by the atom
coupled to a single cavity mode is described by the Rabi Hamiltonian. We show
that, in the dispersive regime, when the modulation periodicity is tuned to the
`resonances', the system dynamics presents the dynamical Casimir effect,
resonant Jaynes-Cummings or resonant Anti-Jaynes-Cummings behaviors, and it can
be described by the corresponding effective Hamiltonians. In the resonant
atom-cavity regime and under the resonant modulation, the dynamics is similar
to the one occurring for a stationary two-level atom in a vibrating cavity, and
an entangled state with two photons can be created from vacuum. Moreover, we
consider the situation in which the atom-cavity coupling, the atomic frequency,
or both have a small nonperiodic time modulation, and show that photons can be
created from vacuum in the dispersive regime. Therefore, an analog of the
dynamical Casimir effect can be simulated in circuit QED, and several photons,
as well as entangled states, can be generated from vacuum due to the
anti-rotating term in the Rabi Hamiltonian.Comment: 14 pages, 6 figures. Talk presented at the International Workshop "60
Years of Casimir Effect", 23 - 27 June, 2008, Brasili
Projected long-term outcomes in patients with type 1 diabetes treated with fast-acting insulin aspart versus conventional insulin aspart in the UK setting
Aims: Many patients with type 1 diabetes mellitus (T1DM) fail to achieve optimal glycemic control and mealtime insulins that more closely match physiological insulin secretion can help improve treatment. In the onset 1 trial, fast-acting insulin aspart (faster aspart) was shown to improve glycemic control in patients with T1DM compared with conventional insulin aspart (insulin aspart). In the UK, faster aspart and insulin aspart are associated with the same acquisition cost, and therefore the present analysis assessed the impact of faster aspart versus insulin aspart on long-term clinical outcomes and costs for patients with T1DM in the UK setting.
Methods: The QuintilesIMS CORE Diabetes Model was used to project clinical outcomes and costs over patient lifetimes in a cohort with baseline characteristics from the onset 1 trial. Treatment effects were taken from the 26-week main phase of the onset 1 trial, with costs and utilities based on literature review. Future costs and clinical benefits were discounted at 3.5% annually.
Results: Projections indicated that faster aspart was associated with improved discounted quality-adjusted life expectancy (by 0.13 quality-adjusted life years) versus insulin aspart). Improved clinical outcomes resulted from fewer diabetes-related complications and a delayed time to their onset with faster aspart. Faster aspart was found to be associated with reduced costs versus insulin aspart (cost savings of GBP 1,715), resulting from diabetes-related complications avoided and reduced treatment costs.
Conclusions: Faster aspart was associated with improved clinical outcomes and cost savings versus insulin aspart for patients with T1DM in the UK setting
Theoretical Properties of Projection Based Multilayer Perceptrons with Functional Inputs
Many real world data are sampled functions. As shown by Functional Data
Analysis (FDA) methods, spectra, time series, images, gesture recognition data,
etc. can be processed more efficiently if their functional nature is taken into
account during the data analysis process. This is done by extending standard
data analysis methods so that they can apply to functional inputs. A general
way to achieve this goal is to compute projections of the functional data onto
a finite dimensional sub-space of the functional space. The coordinates of the
data on a basis of this sub-space provide standard vector representations of
the functions. The obtained vectors can be processed by any standard method. In
our previous work, this general approach has been used to define projection
based Multilayer Perceptrons (MLPs) with functional inputs. We study in this
paper important theoretical properties of the proposed model. We show in
particular that MLPs with functional inputs are universal approximators: they
can approximate to arbitrary accuracy any continuous mapping from a compact
sub-space of a functional space to R. Moreover, we provide a consistency result
that shows that any mapping from a functional space to R can be learned thanks
to examples by a projection based MLP: the generalization mean square error of
the MLP decreases to the smallest possible mean square error on the data when
the number of examples goes to infinity
Tests of Lorentz violation in muon antineutrino to electron antineutrino oscillations
A recently developed Standard-Model Extension (SME) formalism for neutrino
oscillations that includes Lorentz and CPT violation is used to analyze the
sidereal time variation of the neutrino event excess measured by the Liquid
Scintillator Neutrino Detector (LSND) experiment. The LSND experiment,
performed at Los Alamos National Laboratory, observed an excess, consistent
with neutrino oscillations, of in a beam of . It
is determined that the LSND oscillation signal is consistent with no sidereal
variation. However, there are several combinations of SME coefficients that
describe the LSND data; both with and without sidereal variations. The scale of
Lorentz and CPT violation extracted from the LSND data is of order
GeV for the SME coefficients and . This solution for
Lorentz and CPT violating neutrino oscillations may be tested by other short
baseline neutrino oscillation experiments, such as the MiniBooNE experiment.Comment: 10 pages, 10 figures, 2 tables, uses revtex4 replaced with version to
be published in Physical Review D, 11 pages, 11 figures, 2 tables, uses
revtex
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