2,103 research outputs found
Thermodynamic fingerprints of non-Markovianity in a system of coupled superconducting qubits
The exploitation and characterization of memory effects arising from the
interaction between system and environment is a key prerequisite for quantum
reservoir engineering beyond the standard Markovian limit. In this paper we
investigate a prototype of non-Markovian dynamics experimentally implementable
with superconducting qubits. We rigorously quantify non-Markovianity
highlighting the effects of the environmental temperature on the Markovian to
non-Markovian crossover. We investigate how memory effects influence, and
specifically suppress, the ability to perform work on the driven qubit. We show
that the average work performed on the qubit can be used as a diagnostic tool
to detect the presence or absence of memory effects.Comment: 9 page
Stationary entanglement in N-atom subradiant degenerate cascade systems
We address ultracold -atom degenerate cascade systems and show that
stationary subradiant states, already observed in the semiclassical regime,
also exist in a fully quantum regime and for a small number of atoms. We
explicitly evaluate the amount of stationary entanglement for the two-atom
configuration and show full inseparability for the three-atom case. We also
show that a continuous variable description of the systems is not suitable to
detect entanglement due to the nonGaussianity of subradiant states.Comment: 4 figure
Human chorionic gonadotropin isoforms in the diagnosis of ectopic pregnancy
This paper has set the scene for re-defining clinical chemistry data for the diagnosis of ectopic pregnancy. Indeed it has proved some assumptions on hCG levels to be false. Professor Iles was/is the principal investigator on these studies
The Art and Science of Drug Titration
A “one-size-fits-all” approach has been the standard for drug dosing, in particular for agents with a wide therapeutic index. The scientific principles of drug titration, most commonly used for medications with a narrow therapeutic index, are to give the patient adequate and effective treatment, at the lowest dose possible, with the aim of minimizing unnecessary medication use and side effects. The art of drug titration involves the interplay of scientific drug titration principles with the clinical expertise of the healthcare provider, and an individualized, patient-centered partnership between the provider and the patient to review the delicate balance of perceived benefits and risks from both perspectives. Drug titration may occur as up-, down-, or cross-titration depending on whether the goal is to reach or maintain a therapeutic outcome, decrease the risk of adverse effects, or prevent withdrawal/discontinuation syndromes or recurrence of disease. Drug titration introduces additional complexities surrounding the conduct of clinical trials and real-world studies, confounding our understanding of the true effect of medications. In clinical practice, wide variations in titration schedules may exist due to a lack of evidence and consensus on titration approaches that achieve an optimal benefit-harm profile. Further, drug titration may be challenging for patients to follow, resulting in suboptimal adherence and may require increased healthcare-related visits and coordination of care amongst providers. Despite the challenges associated with drug titration, it is a personalized approach to drug dosing that blends science with art, and with supportive real-world outcomes-based evidence, can be effective for optimizing pharmacotherapeutic outcomes and improving drug safety
A simple trapped-ion architecture for high-fidelity Toffoli gates
We discuss a simple architecture for a quantum Toffoli gate implemented using
three trapped ions. The gate, which in principle can be implemented with a
single laser-induced operation, is effective under rather general conditions
and is strikingly robust (within any experimentally realistic range of values)
against dephasing, heating and random fluctuations of the Hamiltonian
parameters. We provide a full characterization of the unitary and
noise-affected gate using three-qubit quantum process tomography
Witnessing entanglement in hybrid systems
We extend the definition of entanglement witnesses based on structure factors
to the case in which the position of the scatterers is quantized. This allows
us to study entanglement detection in hybrid systems. We provide several
examples that show how these extra degrees of freedom affect the detection of
entanglement by directly contributing to the measurement statistics. We
specialize the proposed witness operators for a chain of trapped ions. Within
this framework, we show how the collective vibronic state of the chain can act
as an undesired quantum environment and how ions quantum motion can affect the
entanglement detection. Finally, we investigate some specific cases where the
method proposed leads to detection of hybrid entanglement.Comment: 6 pages, 4 figure
First results with non-perturbative fermion improvement
We present initial results for light hadron masses and nucleon structure
functions using a recent proposal for eliminating all effects from
Wilson fermion simulations in the quenched approximation. With initially
limited statistics, we find a much more linear APE plot and a value of the
axial coupling nearer to the experimental point than with comparable runs
using unimproved Wilson fermions.Comment: 3 pages, 2 PostScript figures, LaTeX 2.09 with espcrc2.sty v2.6,
amstex and epsf, talk presented at LATTICE96(phenomenology) by P. Stephenso
Assessment of the impacts of clear-cutting on soil loss by water erosion in Italian forests: First comprehensive monitoring and modelling approach
Abstract As a member of the European Union, Italy has committed to the maintenance and protection of its forests based on sustainable forest development and management practices. According to Eurostat, Italy has the seventh largest forest surface available for wood supply in the EU-28, which is equal to 8.086 million hectares. For 2012, the Italian National Institute of Statistics estimated the total roundwood production of Italy to be 7.7 million m3, from a harvested forest surface of 61,038 ha. Large parts of the country's forests, mainly located in vulnerable mountainous landscapes that are highly sensitive to environmental changes, are subject to anthropogenic disturbance driven by wood supply interests. Despite the extensive logging activities and the well-known impacts that such management practices have on the soil-related forest ecosystems, there is a lack of spatially and temporally explicit information about the removal of trees. Hence, this study aims to: i) assess the soil loss by water erosion in Italian forest areas, ii) map forest harvests and iii) evaluate the effects of logging activities in terms of soil loss by means of comprehensive remote sensing and GIS modelling techniques. The study area covers about 785.6 × 104 ha, which corresponds to the main forest units of the CORINE land cover 2006 database (i.e. broad-leaved forests, coniferous forests and mixed forests). Annual forest logging activities were mapped using Landsat imagery. Validation procedures were applied. A revised version of the Universal Soil Loss Equation (USLE) was used to predict the soil loss potential due to rill and inter-rill processes. To ensure a thorough modelling approach, the input parameters were calculated using the original methods reported in the USDA handbooks. The derived high-resolution data regarding forest cover change shows that 317,535 ha (4.04% of the total forest area in Italy) were harvested during the period under review. The predicted long-term annual average soil loss rate was 0.54 Mg ha− 1 yr− 1. The average rate of soil loss in forests that remained undisturbed during the modelled period is equal to 0.33 Mg ha− 1 yr− 1. Notably, about half of the soil loss (45.3%) was predicted for the logged areas, even though these cover only about 10.6% of the Italian forests. The identified erosion hotspots may represent a serious threat for the soil-related forest ecosystems, and are in contrast to the EC Thematic Strategy for Soil Protection and Water Framework Directive
Clozapine and hematologic adverse reactions: Impact of the Risk Evaluation and Mitigation Strategy program
Introduction: In October 2015, the Food and Drug Administration (FDA) instituted an update to the mandatory Risk Evaluation and Mitigation Strategy (REMS) program for clozapine to improve safety monitoring of hematologic events. However, the impact of the clozapine REMS program on reporting of hematologic adverse events has not been quantified.
Methods: We assessed adverse event reports for agranulocytosis, granulocytopenia, leukopenia, and neutropenia from the FDA Adverse Event Reporting System (FAERS) for a 1-year time period before (October 2014 to September 2015, pre-REMS) and after (October 2015 to September 2016, post-REMS) the implementation of the clozapine REMS program. The AERSMine platform was used to capture historical effect estimates (October 2004 to September 2014). Reporting odds ratios (ROR), proportional reporting ratios (PRR), and corresponding Taylor series 95% confidence intervals (CIs) were calculated for hematologic events with clozapine compared with all other medications using OpenEpi.
Results: Reporting rates for agranulocytosis, granulocytopenia, leukopenia, and neutropenia with clozapine all increased from the pre-REMS to post-REMS time frames, ranging from a 2-fold increase with leukopenia to a 40-fold increase with neutropenia; the composite measure of all hematologic reports had a 12-fold increase. During the post-REMS time frame, the ROR increased by 1691% (111.4, 95% CI 100.6-123.4) compared with the pre-REMS time frame (7.1, 95% CI 5.2-9.6), and the PRR increased by 1280% (83.1, 95% CI 76.8-90.0 vs 6.9, 95% CI 5.1-9.4) for the composite outcome.
Discussion: We observed significant increases in reports of hematologic adverse events with clozapine after the introduction of the clozapine REMS program. Future research should explore the impact of the less stringent exclusionary and discontinuation criteria on utilization (eg, expanded access) and clinical outcomes (eg, treatment effectiveness and adverse events)
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