1,539 research outputs found
A Note on the correspondence between Qubit Quantum Operations and Special Relativity
We exploit a well-known isomorphism between complex hermitian
matrices and , which yields a convenient real vector
representation of qubit states. Because these do not need to be normalized we
find that they map onto a Minkowskian future cone in , whose
vertical cross-sections are nothing but Bloch spheres. Pure states are
represented by light-like vectors, unitary operations correspond to special
orthogonal transforms about the axis of the cone, positive operations
correspond to pure Lorentz boosts. We formalize the equivalence between the
generalized measurement formalism on qubit states and the Lorentz
transformations of special relativity, or more precisely elements of the
restricted Lorentz group together with future-directed null boosts. The note
ends with a discussion of the equivalence and some of its possible
consequences.Comment: 6 pages, revtex, v3: revised discussio
A Simple n-Dimensional Intrinsically Universal Quantum Cellular Automaton
We describe a simple n-dimensional quantum cellular automaton (QCA) capable
of simulating all others, in that the initial configuration and the forward
evolution of any n-dimensional QCA can be encoded within the initial
configuration of the intrinsically universal QCA. Several steps of the
intrinsically universal QCA then correspond to one step of the simulated QCA.
The simulation preserves the topology in the sense that each cell of the
simulated QCA is encoded as a group of adjacent cells in the universal QCA.Comment: 13 pages, 7 figures. In Proceedings of the 4th International
Conference on Language and Automata Theory and Applications (LATA 2010),
Lecture Notes in Computer Science (LNCS). Journal version: arXiv:0907.382
The Conal representation of Quantum States and Non Trace-Preserving Quantum Operations
We represent generalized density matrices of a -complex dimensional
quantum system as a subcone of a real pointed cone of revolution in
, or indeed a Minkowskian cone in .
Generalized pure states correspond to certain future-directed light-like
vectors of . This extension of the Generalized Bloch
Sphere enables us to cater for non-trace-preserving quantum operations, and in
particluar to view the per-outcome effects of generalized measurements. We show
that these consist of the product of an orthogonal transform about the axis of
the cone of revolution and a positive real linear transform. We give detailed
formulae for the one qubit case and express the post-measurement states in
terms of the initial state vectors and measurement vectors. We apply these
results in order to find the information gain versus disturbance tradeoff in
the case of two equiprobable pure states. Thus we recover Fuchs and Peres'
formula in an elegant manner.Comment: 11 pages, revtex, v3: some typos correcte
SENSITIVITY OF TRANSPORT MODEL TO HYDRAULIC MODEL FOR FLOOD RISK ASSESSMENT OF ROAD INFRASTRUCTURES
El valor terapéutico en oncología. la perspectiva de pacientes, familiares y profesionales
Objective: The aim of the study is to explore if cancer patients actively participate in their care and are involved in treatment decisions. Method: 4 focus groups were organized for a total of 29 participants. One group with patients older than 63 years old, one group with patients younger than 63 years old and one group with caregivers. Moreover, one group was held with the participation of oncologists. Results: Participants have identified the need to receive clear information about treatment options, besides professionals’ advice and experience. Communication skills must be given to professionals; moreover patients need a referent who can accompany them during making decision process. Conclusions: Patients are taking new roles, are more participatory and want to assume more responsibilities about clinical decisions. Patients have a right to understand their illness, prognosis and treatment options. More training programs for physicians are need in order to tailor treatment options to patients’ preferences and needs.Objetivo: El objetivo de este estudio es valorar en qué medida los afectados de cáncer asumen actitudes de participación en relación al propio plan terapéutico, además de conocer la opinión de familiares y la de los profesionales que les atienden. Método: Se organizaron 4 grupos focales, con un total de 29 participantes. Un grupo con afectados mayores de 63 años, un grupo con afectados menores de 63 años y un grupo con familiares de afectados por distintas patologías oncológicas. Además, se organizó un grupo con profesionales sanitarios para conocer su opinión. Resultados: Los participantes de los distintos grupos han identificado la necesidad de disponer de información clara acerca de las posibilidades terapéuticas, además de los consejos y la experiencia que puede aportar el profesional. Debería realizarse formación en habilidades de comunicación, además de contar con un profesional de referencia que pueda ofrecer orientación y apoyo durante el proceso de toma de decisiones. Conclusiones: Existe en la actualidad un nuevo rol de paciente con un perfi l más activo, que desea asumir mayor responsabilidad en las decisiones clínicas. Los pacientes tienen el derecho a recibir la información sobre la propia enfermedad, el pronóstico y las opciones terapéuticas disponibles. Es necesaria mayor formación a los profesionales sanitarios que permita ajustar las opciones terapéuticas a las necesidades y preferencias de los pacientes y familiares
The development a spanish questionnaire to assess cancer survivors’ unmet needs (CESC)
Introducción: Según datos de la SEOM, existen en la actualidad más de un millón y medio de supervivientes de cáncer en España. El objetivo de este estudio es el desarrollo y evaluación de un cuestionario para medir las necesidades no cubiertas de supervivientes de cáncer. Método: Se desarrolló y evaluó un cuestionario auto-administrado para detectar las necesidades no cubiertas de supervivientes de cáncer. Durante la Fase 1 se definió el constructo, se revisó la literatura científica y se consideró un estudio cualitativo desarrollado previamente. La propuesta del Cuestionario Español para Medir Necesidades no Cubiertas de Supervivientes de Cáncer (CESC) se evaluó sucesivamente por un panel de expertos hasta obtener una versión que incluye las propuestas formuladas. En la Fase 2, el cuestionario fue completado por un total de 109 supervivientes de cáncer, a fin de analizar sus propiedades psicométricas. Resultados: El cuestionario CESC incluyó un total de 25 ítems o necesidades relevantes, mostrando tener buenas propiedades de fiabilidad y validez. Como resultado del análisis estadístico se obtuvieron 3 Factores: físico, emocional y laboral-económico. Conclusiones: El cuestionario CESC es un primer instrumento disponible en español, para facilitar la detección de necesidades de servicios específicos dirigidos a la población de supervivientes de cáncer. Los resultados, si bien preliminares, son muy alentadores.Background: To develop and evaluate a questionnaire to measure cancer survivors’ unmet needs. Methods: A self-report measure of cancer survivors’ unmet needs was developed. In Phase I, it was taken into consideration the construct definition, literature review and previous qualitative research that identified needs in survivors. Spanish Questionnaire of Cancer Survivors’ Unmet Needs (CESC) was review by an expert panel up to the final version. In Phase 2, the measure was completed by 109 cancer survivors. Results: CESC questionnaire included 25 need items. Good acceptability, internal consistency and validity were demonstrated. Factor analysis identified three factors: Physical, Emotional and Employment/Economic. Conclusions: The CESC, first instrument in Spanish, will facilitate the evaluation of target services and generation of service delivery recommendations for cancer survivors. Even if it is a preliminary version, results are encouraging
Some effects of high-frequency x-rays on the oyster drill Urosalpinx cinerea
Scientists of ·the.Department of Agriculture (Bushland et al. 1955) recently announced the successful eradication of the screw-worm, Callitroga hominivorax, from the Dutch Island of Curacao. This was accomplished by releasing x-ray steralized males, which competed successfully with normal indigenous males for the females. After such matings the monogamous females deposited only sterile egg masses. Although several releases, Were necessary, eventually no fertile eggs Were detected at any of the.numerous observation points. Subsequent checks failed to reveal any live flies.
Because existing information concerning ecology and reproduction of drills appeared favorable, our group was encouraged to investigate this technique as a possible control method for oyster drills. The present paper is a report; of a· series of experiments which were designed to determine the lethal dose
A Polányi-féle "kettős mozgás" : a brit és az amerikai hegemónia Belle Époque-jainak összehasonlítása
E cikk középpontjában a késő tizennyolcadik-kora tizenkilencedik század kettős mozgása (a
brit hegemónia belle époque-ja és összeomlása), illetve a késő huszadik - kora tizenkilencedik század
kettős mozgása (az amerikai hegemónia belle époque-ja és jelen válsága) összehasonlító elemzése
áll. Az elmozdulás az állítólagosan önszabályozó piac irányába mindkét időszakban protekcionista
ellenreakciókat váltott ki. Mindazonáltal jelentős különbségeket is felfedezhetünk – egyrészről a
hegemón állam jellegének eltéréseiből fakadóan, másrészt abban, hogy az alárendelt erők a késő
huszadik században jóval nagyobb szerepet játszottak abban, hogy elmozdulás történjen a piaci
önszabályozás irányába
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