1,152 research outputs found
Very Prolonged Treatment with Albendazole of a Case of Disseminated Abdominal Cystic Echinococcosis
Cystic echinococcosis is a zoonosis caused by the ingestion of food or water contaminated by Echinococcus eggs. E. granulosus is the most common causative agent of cystic echinococcosis that still has a relevant incidence in Italy, especially on the islands of Sicily and Sardinia. We report the case of a 64-year-old man with disseminated abdominal cystic echinococcosis (liver, spleen, peritoneum). The patient was asymptomatic and non-eligible for surgical treatment. Treatment with albendazole 400 mg/twice daily was started in 2012 for 15 cycles (each cycle consisted of three 28-day treatments at 14-day intervals) over 10 years for a total of 1260 days of treatment. Serum anti-Echinococcus antibody titers and imaging (echography, TC) were evaluated to monitor the evolution of the disease. Imaging techniques documented the regression of all cyst lesions, but it was less evident for the peritoneal localizations that still are in follow-up. In this case, the prolonged treatment with albendazole was effective, safe and free of side effects. Until today, the patient displays a good clinical condition
Dynamics of quantum correlations in colored environments
We address the dynamics of entanglement and quantum discord for two non
interacting qubits initially prepared in a maximally entangled state and then
subjected to a classical colored noise, i.e. coupled with an external
environment characterized by a noise spectrum of the form . More
specifically, we address systems where the Gaussian approximation fails, i.e.
the sole knowledge of the spectrum is not enough to determine the dynamics of
quantum correlations. We thus investigate the dynamics for two different
configurations of the environment: in the first case the noise spectrum is due
to the interaction of each qubit with a single bistable fluctuator with an
undetermined switching rate, whereas in the second case we consider a
collection of classical fluctuators with fixed switching rates. In both cases
we found analytical expressions for the time dependence of entanglement and
quantum discord, which may be also extended to a collection of flcutuators with
random switching rates. The environmental noise is introduced by means of
stochastic time-dependent terms in the Hamiltonian and this allows us to
describe the effects of both separate and common environments. We show that the
non-Gaussian character of the noise may lead to significant effects, e.g.
environments with the same power spectrum, but different configurations, give
raise to opposite behavior for the quantum correlations. In particular,
depending on the characteristics of the environmental noise considered, both
entanglement and discord display either a monotonic decay or the phenomena of
sudden death and revivals. Our results show that the microscopic structure of
environment, besides its noise spectrum, is relevant for the dynamics of
quantum correlations, and may be a valid starting point for the engineering of
non-Gaussian colored environments.Comment: 8 pages, 3 figure
Entanglement dynamics of electron-electron scattering in low-dimensional semiconductor systems
We perform the quantitative evaluation of the entanglement dynamics in
scattering events between two insistinguishable electrons interacting via
Coulomb potential in 1D and 2D semiconductor nanostructures. We apply a
criterion based on the von Neumann entropy and the Schmidt decomposition of the
global state vector suitable for systems of identical particles. From the
timedependent numerical solution of the two-particle wavefunction of the
scattering carriers we compute their entanglement evolution for different spin
configurations: two electrons with the same spin, with different spin, singlet,
and triplet spin state. The procedure allows to evaluate the mechanisms that
govern entanglement creation and their connection with the characteristic
physical parameters and initial conditions of the system. The cases in which
the evolution of entanglement is similar to the one obtained for
distinguishable particles are discussed.Comment: 22 pages, 7 figures, submitted to Physical Review
Impact of Nursing Education on Postoperative Ileus Prevention in a Tertiary Care Facility: A Quality Improvement Project
Postoperative ileus (POI) is a preventable but potentially fatal complication that affects approximately 10% to 30% of patients who undergo major abdominal surgery. Despite the use of Enhanced Recovery After Surgery (ERAS) protocols, tertiary care facilities continue to struggle with this complication affecting not only patient outcomes but also healthcare cost and revenue generation. Although hospitals often offer general education to staff nurses throughout the year, the topics are mainly designed to target national accreditation requirements. This leaves a knowledge gap on specific skills and interventions that could greatly improve health outcomes. To address this issue, a quality improvement project to increase nurse knowledge of POI was implemented in an acute tertiary care facility in the Miami area. A total of 43 registered nurses working in two inpatient step-down units were included in this project. The results were analyzed and a significant increase in mean scores for knowledge and confidence before and after the education intervention were noted. Overall, there was a 34% increase in mean confidence self-assessment score and a 109% increase in knowledge mean scores when compared to baseline. Although a power analysis was not performed, a paired one-tailed t-test was executed to determine statistical significance showing a result of p \u3c 0.0001. The data shows that nurse education is effective at enhancing knowledge and confidence when identifying, preventing, and treating POI. Based on the evidence and the results of this project, future education should be implemented and the material incorporated into onboarding curriculums for surgical units
Localization of sentinel lymph node in breast cancer. A prospective study
Introduction: Sentinel Lymph Node Biopsy (SLNB) is the standard of care for staging axillary lymph nodes
in women with breast cancer and clinically negative nodes. It is associated with reduced arm morbidity,
moderated or severe lymphoedema, and a better quality of life in comparison with standard axillary
treatment. Unfortunately, skip metastases makes all minimally invasive approaches, such as axillary
sampling, unreliable. The aim of the present clinical prospective study is to evaluate the position of SLN
in an important number of cases and establish the real incidence of skip metastases in clinically nodenegative
patients.
Patients and methods: A cohort of 898 female patients with breast carcinoma was considered, from 2001
to 2008. Once SLN was localized, by means of radio-colloid or blue dye staining, and isolated, a biopsy
was performed. Only those positive for metastases were submitted to axillary dissection.
Results: Only in nine cases a SLN was not isolated. We had 819 cases of first level SLN (group A) and 69
cases of second level SLN (group B). Considering all of 889 cases, SLN was localized in the second level in
69 patients (7.8%); but if we consider metastatic SLN alone (340 cases), it was in the second level in 23
subjects (6.8%). In total, we had a positive second level SLN in 2.3% of cases (23/889).
Conclusion: Second level SLN could be considered only an anomalous lymphatic axillary drainage and it
does not linked to particular histological variants of the primitive tumour. In our study, skip metastases
were recognized in only 2.6% of cases, therefore, whenever a SLN is not isolated for any reason, the first
level sampling represent a viable operative choice
There exist non orthogonal quantum measurements that are perfectly repeatable
We show that, contrarily to the widespread belief, in quantum mechanics
repeatable measurements are not necessarily described by orthogonal
projectors--the customary paradigm of "observable". Nonorthogonal
repeatability, however, occurs only for infinite dimensions. We also show that
when a non orthogonal repeatable measurement is performed, the measured system
retains some "memory" of the number of times that the measurement has been
performed.Comment: 4 pages, 1 figure, revtex4, minor change
Spatio-temporal overview of neuroinflammation in an experimental mouse stroke model.
After ischemic stroke, in the lesion core as well as in the ischemic penumbra, evolution of tissue damage and repair is strongly affected by neuroinflammatory events that involve activation of local specialized glial cells, release of inflammatory mediators, recruiting of systemic cells and vascular remodelling. To take advantage of this intricate response in the quest to devise new protective therapeutic strategies we need a better understanding of the territorial and temporal interplay between stroke-triggered inflammatory and cell death-inducing processes in both parenchymal and vascular brain cells. Our goal is to describe structural rearrangements and functional modifications occurring in glial and vascular cells early after an acute ischemic stroke. Low and high scale mapping of the glial activation on brain sections of mice subjected to 30 minutes middle cerebral artery occlusion (MCAO) was correlated with that of the neuronal cell death, with markers for microvascular changes and with markers for pro-inflammatory (IL-1β) and reparative (TGFβ1) cytokines. Our results illustrate a time-course of the neuroinflammatory response starting at early time-points (1 h) and up to one week after MCAO injury in mice, with an accurate spatial distribution of the observed phenomena
Global information balance in quantum measurements
We perform an information-theoretical analysis of quantum measurement
processes and obtain the global information balance in quantum measurements, in
the form of a closed chain equation for quantum mutual entropies. Our balance
provides a tight and general entropic information-disturbance trade-off, and
explains the physical mechanism underlying it. Finally, the single-outcome
case, that is, the case of measurements with post-selection, is briefly
discussed.Comment: Final version to appear on Physical Review Letter
Entanglement measures and approximate quantum error correction
It is shown that, if the loss of entanglement along a quantum channel is
sufficiently small, then approximate quantum error correction is possible,
thereby generalizing what happens for coherent information. Explicit bounds are
obtained for the entanglement of formation and the distillable entanglement,
and their validity naturally extends to other bipartite entanglement measures
in between. Robustness of derived criteria is analyzed and their tightness
compared. Finally, as a byproduct, we prove a bound quantifying how large the
gap between entanglement of formation and distillable entanglement can be for
any given finite dimensional bipartite system, thus providing a sufficient
condition for distillability in terms of entanglement of formation.Comment: 7 pages, two-columned revtex4, no figures. v1: Deeply revised and
extended version: different entanglement measures are separately considered,
references are added, and some remarks are stressed. v2: Added a sufficient
condition for distillability in terms of entanglement of formation; published
versio
On demand entanglement in double quantum dots via coherent carrier scattering
We show how two qubits encoded in the orbital states of two quantum dots can
be entangled or disentangled in a controlled way through their interaction with
a weak electron current. The transmission/reflection spectrum of each scattered
electron, acting as an entanglement mediator between the dots, shows a
signature of the dot-dot entangled state. Strikingly, while few scattered
carriers produce decoherence of the whole two-dots system, a larger number of
electrons injected from one lead with proper energy is able to recover its
quantum coherence. Our numerical simulations are based on a real-space solution
of the three-particle Schroedinger equation with open boundaries. The computed
transmission amplitudes are inserted in the analytical expression of the system
density matrix in order to evaluate the entanglement.Comment: 20 pages, 5 figure
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