On the local unitary equivalence of states of multi-partite systems

Two pure states of a multi-partite system are alway are related by a unitary transformation acting on the Hilbert space of the whole system. This transformation involves multi-partite transformations. On the other hand some quantum information protocols such as the quantum teleportation and quantum dense coding are based on equivalence of some classes of states of bi-partite systems under the action of local (one-particle) unitary operations. In this paper we address the question: ``Under what conditions are the two states states, $\varrho$ and $\sigma$, of a multi-partite system locally unitary equivalent?'' We present a set of conditions which have to be satisfied in order that the two states are locally unitary equivalent. In addition, we study whether it is possible to prepare a state of a multi-qudit system. which is divided into two parts A and B, by unitary operations acting only on the systems A and B, separately.Comment: 6 revtex pages, 1 figur

Quantum Zeno tomography

We show that the resolution "per absorbed particle" of standard absorption tomography can be outperformed by a simple interferometric setup, provided that the different levels of "gray" in the sample are not uniformly distributed. The technique hinges upon the quantum Zeno effect and has been tested in numerical simulations. The scheme we propose could be implemented in experiments with UV-light, neutrons or X-rays.Comment: 8 pages, 5 figure

Microwave cavity-enhanced transduction for plug and play nanomechanics at room temperature

Nanomechanical resonators with increasingly high quality factors are enabled following recent insights into energy storage and loss mechanisms in nanoelectromechanical systems (NEMS). Consequently, efficient, non-dissipative transduction schemes are required to avoid the dominating influence of coupling losses. We present an integrated NEMS transducer based on a microwave cavity dielectrically coupled to an array of doubly-clamped pre-stressed silicon nitride beam resonators. This cavity-enhanced detection scheme allows resolving the resonators' Brownian motion at room temperature while preserving their high mechanical quality factor of 290,000 at 6.6 MHz. Furthermore, our approach constitutes an "opto"mechanical system in which backaction effects of the microwave field are employed to alter the effective damping of the resonators. In particular, cavity-pumped self-oscillation yields a linewidth of only 5 Hz. Thereby, an adjustement-free, all-integrated and self-driven nanoelectromechanical resonator array interfaced by just two microwave connectors is realised, potentially useful for applications in sensing and signal processing

Kindlin-3 loss curbs chronic myeloid leukemia in mice by mobilizing leukemic stem cells from protective bone marrow niches.

Kindlin-3 (K3)-mediated integrin adhesion controls homing and bone marrow (BM) retention of normal hematopoietic cells. However, the role of K3 in leukemic stem cell (LSC) retention and growth in the remodeled tumor-promoting BM is unclear. We report that loss of K3 in a mouse model of chronic myeloid leukemia (CML) triggers the release of LSCs from the BM into the circulation and impairs their retention, proliferation, and survival in secondary organs, which curbs CML development, progression, and metastatic dissemination. We found de novo expression of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) on CML-LSCs but not normal hematopoietic stem cells and this enabled us to specifically deplete K3 with a CTLA-4-binding RNA aptamer linked to a K3-siRNA (small interfering RNA) in CTLA-4+ LSCs in vivo, which mobilized LSCs in the BM, induced disease remission, and prolonged survival of mice with CML. Thus, disrupting interactions of LSCs with the BM environment is a promising strategy to halt the disease-inducing and relapse potential of LSCs

How many photons are needed to distinguish two transparencies?

We give a bound on the minimum number of photons that must be absorbed by any quantum protocol to distinguish between two transparencies. We show how a quantum Zeno method in which the angle of rotation is varied at each iteration can attain this bound in certain situations.Comment: 5 pages, 4 figure

Sklerodermie und fibrosierende Erkrankungen

Zusammenfassung: Bei der Sklerodermie und anderen fibrosierenden Erkrankungen wie den Fibromatosen, der Arthrofibrose und dem M.Ormond liegt eine Fibroblastenproliferation mit mehr oder weniger starker Begleitentzündung vor. Bei der Sklerodermie kommt es zu einer Hautfibrose mit obstruktiver Vaskulopathie. Sklerodermiforme Hautveränderungen werden auch im Rahmen der "Graft-versus-Host-Disease" nach hämatopoetischer Stammzelltransplantation, bei Malignomen und nach Applikation bestimmter Medikamente beobachtet. Die Fibromatosen werden in eine unter der Hautoberfläche gelegene Gruppe und die tief im Körper lokalisierten Desmoide unterteilt. Im Rahmen des M.Ormond findet sich eine Aortitis mit Ausdehnung der fibrosierenden Entzündung in den Retroperitonealraum. Die Bedeutung der histopathologischen Diagnostik bei fibrosierenden Erkrankungen ist unterschiedlich und reicht von einer erkrankungsbestätigenden bis hin zu einer erkankungsdefinierenden Diagnos

Generation of multi-modal dialogue for a net environment

In this paper an architecture and special purpose markup language for simulated affective face-to-face communication is presented. In systems based on this architecture, users will be able to watch embodied conversational agents interact with each other in virtual locations on the internet. The markup language, or Rich Representation Language (RRL), has been designed to provide an integrated representation of speech, gesture, posture and facial animation