110 research outputs found
Complex renal masses: Partial or no partial nephrectomy?
Management of high complexity renal masses is always challenging for urologists. Beksac and co-workers made a great effort in collecting data from 144 patients with complex renal masses defined as a RENAL score higher than 10 undergoing robotic partial nephrectomy (RPN). Trifecta was achieved in 62% of the patients. The multi-center design of the study is an important feature considering that 6 surgeons were involved. The study is retrospective and follow up is short therefore data should be managed with caution. Their study confirms the available evidence on the subject, confirming that in expert hands RPN should be performed whenever deemed feasible
MOCVD Growth of ZnO Nanowires Through Colloidal and Sputtered Au Seed Via Zn[TMHD]2 Precursor
AbstractZinc oxide (ZnO) nanowire (NW) arrays were grown on Si (100) substrate by metal-organic chemical vapor deposition (MOCVD) via Zn[TMHD]2 as precursor. Here we adopted two different procedures to grow ZnO NWs namely, colloid and sputtered Au pre-deposition on Si (100) substrate. Comparative studies based on the morphology and growth behavior of ZnO NWs were performed. The grown ZnO NWs were characterized by field-emission scanning electron microscopy (FE-SEM), Atomic Force Microscopy (AFM), Co-focal laser scanning microscopy (CLSM), and Raman spectroscopy
Asymptotic entanglement in a two-dimensional quantum walk
The evolution operator of a discrete-time quantum walk involves a conditional
shift in position space which entangles the coin and position degrees of
freedom of the walker. After several steps, the coin-position entanglement
(CPE) converges to a well defined value which depends on the initial state. In
this work we provide an analytical method which allows for the exact
calculation of the asymptotic reduced density operator and the corresponding
CPE for a discrete-time quantum walk on a two-dimensional lattice. We use the
von Neumann entropy of the reduced density operator as an entanglement measure.
The method is applied to the case of a Hadamard walk for which the dependence
of the resulting CPE on initial conditions is obtained. Initial states leading
to maximum or minimum CPE are identified and the relation between the coin or
position entanglement present in the initial state of the walker and the final
level of CPE is discussed. The CPE obtained from separable initial states
satisfies an additivity property in terms of CPE of the corresponding
one-dimensional cases. Non-local initial conditions are also considered and we
find that the extreme case of an initial uniform position distribution leads to
the largest CPE variation.Comment: Major revision. Improved structure. Theoretical results are now
separated from specific examples. Most figures have been replaced by new
versions. The paper is now significantly reduced in size: 11 pages, 7 figure
Microscopic observation of magnon bound states and their dynamics
More than eighty years ago, H. Bethe pointed out the existence of bound
states of elementary spin waves in one-dimensional quantum magnets. To date,
identifying signatures of such magnon bound states has remained a subject of
intense theoretical research while their detection has proved challenging for
experiments. Ultracold atoms offer an ideal setting to reveal such bound states
by tracking the spin dynamics after a local quantum quench with single-spin and
single-site resolution. Here we report on the direct observation of two-magnon
bound states using in-situ correlation measurements in a one-dimensional
Heisenberg spin chain realized with ultracold bosonic atoms in an optical
lattice. We observe the quantum walk of free and bound magnon states through
time-resolved measurements of the two spin impurities. The increased effective
mass of the compound magnon state results in slower spin dynamics as compared
to single magnon excitations. In our measurements, we also determine the decay
time of bound magnons, which is most likely limited by scattering on thermal
fluctuations in the system. Our results open a new pathway for studying
fundamental properties of quantum magnets and, more generally, properties of
interacting impurities in quantum many-body systems.Comment: 8 pages, 7 figure
Quantum walks: a comprehensive review
Quantum walks, the quantum mechanical counterpart of classical random walks,
is an advanced tool for building quantum algorithms that has been recently
shown to constitute a universal model of quantum computation. Quantum walks is
now a solid field of research of quantum computation full of exciting open
problems for physicists, computer scientists, mathematicians and engineers.
In this paper we review theoretical advances on the foundations of both
discrete- and continuous-time quantum walks, together with the role that
randomness plays in quantum walks, the connections between the mathematical
models of coined discrete quantum walks and continuous quantum walks, the
quantumness of quantum walks, a summary of papers published on discrete quantum
walks and entanglement as well as a succinct review of experimental proposals
and realizations of discrete-time quantum walks. Furthermore, we have reviewed
several algorithms based on both discrete- and continuous-time quantum walks as
well as a most important result: the computational universality of both
continuous- and discrete- time quantum walks.Comment: Paper accepted for publication in Quantum Information Processing
Journa
Digital image processing with quantum approaches
Digital image processing with quantum approaches
Eligibility criteria for Menopausal Hormone Therapy (MHT): a position statement from a consortium of scientific societies for the use of MHT in women with medical conditions. MHT Eligibility Criteria Group
This project aims to develop eligibility criteria for menopausal hormone therapy (MHT). The tool should be
similar to those already established for contraception A consortium of scientific societies coordinated by the
Spanish Menopause Society met to formulate recommendations for the use of MHT by women with medical conditions based on the best available evidence. The project was developed in two phases. As a first step, we
conducted 14 systematic reviews and 32 metanalyses on the safety of MHT (in nine areas: age, time of menopause
onset, treatment duration, women with thrombotic risk, women with a personal history of cardiovascular
disease, women with metabolic syndrome, women with gastrointestinal diseases, survivors of breast cancer or of
other cancers, and women who smoke) and on the most relevant pharmacological interactions with MHT. These
systematic reviews and metanalyses helped inform a structured process in which a panel of experts defined the
eligibility criteria according to a specific framework, which facilitated the discussion and development process.
To unify the proposal, the following eligibility criteria have been defined in accordance with the WHO international
nomenclature for the different alternatives for MHT (category 1, no restriction on the use of MHT;
category 2, the benefits outweigh the risks; category 3, the risks generally outweigh the benefits; category 4,
MHT should not be used). Quality was classified as high, moderate, low or very low, based on several factors
(including risk of bias, inaccuracy, inconsistency, lack of directionality and publication bias). When no direct
evidence was identified, but plausibility, clinical experience or indirect evidence were available, "Expert opinion"
was categorized. For the first time, a set of eligibility criteria, based on clinical evidence and developed according
to the most rigorous methodological tools, has been defined. This will provide health professionals with a
powerful decision-making tool that can be used to manage menopausal symptoms
International recommendations for glucose control in adult non diabetic critically ill patients
The purpose of this research is to provide recommendations for the management of glycemic control in critically ill patients.Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishedPour la Société Française d'Anesthésie-Réanimation (SFAR); Société de Réanimation de langue Française (SRLF) and the Experts grou
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