28,458 research outputs found
Weak values and the quantum phase space
We address the issue of how to properly treat, and in a more general setting,
the concept of a weak value of a weak measurement in quantum mechanics. We show
that for this purpose, one must take in account the effects of the measuring
process on the entire phase space of the measuring system. By using coherent
states, we go a step further than Jozsa in a recent paper, and we present an
example where the result of the measurement is symmetrical in the position and
momentum observables and seems to be much better suited for quantum optical
implementation.Comment: 07 pages, accepted for PR
The Electronic States of Two Oppositely doped Mott Insulators Bilayers
We study the effect of Coulomb interaction between two oppositely doped
low-dimensional tJ model systems. We exactly show that, in the one-dimensional
case, an arbitrarily weak interaction leads to the formation of charge neutral
electron-hole pairs. We then use two different mean-field theories to address
the two-dimensional case, where inter-layer excitons also form and condense. We
propose that this results in new features which have no analog in single
layers, such as the emergence of an insulating spin liquid phase. Our simple
bilayer model might have relevance to the physics of doped Mott insulator
interfaces and of the new four layer Ba2CaCu4O8 compound.Comment: 4 pages, 1 figur
Sustainable forest management of miombo woodlands in Niassa National Reserve, northern Mozambique: a multidisciplinary approach of fire resistance analysis.
Poster presented at XIII World Forestry Congress. Buenos Aires (Argentina). 18 - 23 Oct 2009
Solid State Analog for He-McKellar-Wilkens Quantum Phase
In this letter we investigate the quantum dynamics of a quasiparticle in the
presence of a charged screw dislocation submitted to a uniform magnetic field.
Analysing the quantum scattering for this quasiparticle we observed the
appearance of a topological quantum phase in the solution and demonstrate that
this phenomenon is the solid state analog of the He-McKeller-Wilkens effect.Comment: 7 pages, epl styl
Sustainable management of miombo woodlands in the Northern part of Mozambique (Niassa National Reserve - NNR).
Poster presented at Commiting Science to Global Development. Lisbon (Portugal). 29-30 Sep 2009
Microstrip resonator for microwaves with controllable polarization
In this work the authors implemented a resonator based upon microstrip
cavities that permits the generation of microwaves with arbitrary polarization.
Design, simulation, and implementation of the resonators were performed using
standard printed circuit boards. The electric field distribution was mapped
using a scanning probe cavity perturbation technique. Electron spin resonance
using a standard marker was carried out in order to verify the polarization
control from linear to circular.Comment: 3 pages, 3 figures, submitted to Appl. Phys. Let
HEALTH-STATE UTILITIES IN CHRONIC IMMUNE DISEASES: PILOT STUDY
HEALTH-STATE UTILITIES IN CHRONIC IMMUNE DISEASES: PILOT STUDY
ClaĂşdia Ribeiro1,2,3, Augusta Silveira4,3, Augusta Marques5, Catarina Ribeiro4, Isabel Santos6,2,3, Carlos Vasconcelos2,3
1UCP, 2HSA/CHP, 3ICBAS/UP, 4UFP, 5HPA e 6HSMF.
Universidade CatĂłlica Portuguesa (UCP), Porto
Hospital de Santo AntĂłnio, Centro Hospitalar do Porto (HSA/CHP), Porto.
Instituto Ciências Biomédicas Abel Salazar, Universidade do Porto (ICBAS/UP), Porto.
Universidade Fernando Pessoa (UFP), Porto.
Hospital Privado da Arrábida (HPA), Porto.
Hospital Santa Maria da Feira (HSMF), Porto.
Background
Utility scores are used to estimate Quality Adjusted Life Years (QALYs), applied in determining the cost-effectiveness of health care interventions. In studies where no preference based measures are collected, indirect methods have been developed to estimate utilities from clinical instruments.
Aim
The aim of this study was to evaluate a published method of estimating the Short Form-6D (SF-6D) (preference based) in patients with chronic immune diseases from Unidade de Imunologia ClĂnica do Hospital de Santo AntĂłnio - Centro Hospitalar do Porto and evaluate the impact of socio demographics economics and clinical characteristics on quality of life (QoL) and potential predictors for QoL improvements.
Methods
We enrolled 320 patients with chronic immune diseases (104 men and 226 women with a mean age: 45.21; 84 people living with HIV and 236 with chronic autoimmune diseases. All responders to the Portuguese SF-36 version 2.0 questionnaire can be assigned an SF-6D score provided the 11 items used in the SF-6D have been completed using a computerized administration. To assess socioeconomic status, we use the Graffer’s scale, clinical and demographic variables were assessed by a questionnaire specifically designed for the present study.
Results
The mean utility value was .595. Male, gender, young, single, individuals with high educational attainment level and Graffer’s scale Class high reported higher utility levels. As expected, those who takes therapeutics’ or have a higher length disease reported lower mean utility levels than those who were in a less severe stadium of the disease or without therapeutic.
Conclusion
This paper provides the first utilities obtained from a populations leave with chronic immune diseases. The preference-based measures used in this study distinguish patient groups with chronic immune diseases’ in terms of socio-demographics characteristics and clinical groups. The normative values can be used economic evaluation and clinical studies as they incorporate patient’s preferences and translate the value attribute to patients´ health state.
Apresentador:
Cláudia Ribeiro, Médica Dentista. Doutoranda, Faculdade de Medicina da Universidade de Santiago de Compostela
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