3,672 research outputs found

    Certified Quantum Measurement of Majorana Fermions

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    We present a quantum self-testing protocol to certify measurements of fermion parity involving Majorana fermion modes. We show that observing a set of ideal measurement statistics implies anti-commutativity of the implemented Majorana fermion parity operators, a necessary prerequisite for Majorana detection. Our protocol is robust to experimental errors. We obtain lower bounds on the fidelities of the state and measurement operators that are linear in the errors. We propose to analyze experimental outcomes in terms of a contextuality witness WW, which satisfies ⟨W⟩≤3\langle W \rangle \le 3 for any classical probabilistic model of the data. A violation of the inequality witnesses quantum contextuality, and the closeness to the maximum ideal value ⟨W⟩=5\langle W \rangle=5 indicates the degree of confidence in the detection of Majorana fermions.Comment: 13 pages, 3 figure

    Measurement Accuracy Investigation of Touch Trigger Probe with Five-Axis Machine Tools

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    The touch trigger probe plays an important role in modern metrology because of its robust and compact design with crash protection, long life and excellent repeatability. Aside from coordinate measuring machines (CMM), touch trigger probes are used for workpiece location on a machine tool and for the accuracy assessment of the machine tools. As a result, the accuracy of the measurement is a matter of interest to the users. The touch trigger probe itself as well as the measuring surface, the machine tool, measuring environment etc. contribute to measurement inaccuracies. The paper presents the effect of surface irregularities, surface wetness due to cutting fluid and probing direction on probing accuracy on a machine tool

    Screening for Inhalational Anthrax Due to Bioterrorism: Evaluating Proposed Screening Protocols

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    Eleven known cases of bioterrorism-related inhalational anthrax (IA) were treated in the United States during 2001. We retrospectively compared 2 methods that have been proposed to screen for IA. The 2 screening protocols for IA were applied to the emergency department charts of patients who presented with possible signs or symptoms of IA at Inova Fairfax Hospital (Falls Church, Virginia) from 20 October 2001 through 3 November 2001. The Mayer criteria would have screened 4 patients (0.4%; 95% CI, 0.1%-0.9%) and generated charges of 1900 dollars. If 29 patients (2.6%; 95% CI, 1.7%-3.7%) with \u3eor=5 symptoms (but without fever and tachycardia) were screened, charges were 13,325 dollars. The Hupert criteria would have screened 273 patients (24%; 95% CI, 22%-27%) and generated charges of 126,025 dollars. In this outbreak of bioterrorism-related IA, applying the Mayer criteria would have identified both patients with IA and would have generated fewer charges than applying the Hupert criteria

    Do People Support Sin Taxes? A Population Survey of Attitudes

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    Abstract Background: The rising costs of healthcare and the recognition that many chronic diseases are preventable by healthy lifestyles have led to inquiry about economic incentives for modifying behavior. The present work explored people's attitudes towards a differential health insurance premium based on lifestyle

    Paretic hand in stroke: from motor cortical plasticity research to rehabilitation

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    Abstract: Research in neural plasticity of adult cortical representations brought hope of significant potential for further improvement in therapy after cerebrovascular stroke, but the same processes involved in plasticity also allow for maladaptive changes whether spontaneous or caused by inappropriate therapeutic manipulations. Within the extensive network of multiple and bilateral motor cortical and subcortical areas, this paper focuses on the primary motor cortex. We review selected data from humans and primates regarding its functional anatomy and the mechanisms of adaptive neuroplasticity in the presence of brain insults, and the impact of motor skill learning in normals and rehabilitation therapy in patients. The discussion centers on the potential impact of the mechanisms of motor cortex neuroplasticity, especially of the phenomenon of competition among primary motor cortical representations, on the rehabilitation of paretic hand and shoulder after stroke. Application of results from neurophysiology and functional brain imaging research into the clinical practice is in the initial stages and remains a challenge for the future. Nevertheless, even the available research provides an important message for clinical rehabilitation of stroke patients: the need to widen multimodal and interdisciplinary approaches to rehabilitation of the paretic hand

    Primordial Earth mantle heterogeneity caused by the Moon-forming giant impact

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    The giant impact hypothesis for Moon formation successfully explains the dynamic properties of the Earth–Moon system but remains challenged by the similarity of isotopic fingerprints of the terrestrial and lunar mantles. Moreover, recent geochemical evidence suggests that the Earth's mantle preserves ancient (or "primordial") heterogeneity that pre-dates the Moon-forming giant impact. Using a new hydrodynamical method, we here show that Moon-forming giant impacts lead to a stratified starting condition for the evolution of the terrestrial mantle. The upper layer of the Earth is compositionally similar to the disk, out of which the Moon evolves, whereas the lower layer preserves proto-Earth characteristics. As long as this predicted compositional stratification can at least partially be preserved over the subsequent billions of years of Earth mantle convection, a compositional similarity between the Moon and the accessible Earth's mantle is a natural outcome of realistic and high-probability Moon-forming impact scenarios. The preservation of primordial heterogeneity in the modern Earth not only reconciles geochemical constraints but is also consistent with recent geophysical observations. Furthermore, for significant preservation of a proto-Earth reservoir, the bulk major-element composition of the Earth–Moon system may be systematically shifted toward chondritic values

    Learner control in animated multimedia instructions

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    The interactivity principle in multimedia learning states that giving learners control over pace and order of instructions decreases cognitive load and increases transfer performance. We tested this guideline by comparing a learner-paced instruction with a system-paced instruction. Time-on-task and interactive behavior were logged, and were also related to interest, prior knowledge, and cognitive involvement. We successfully replicated the interactivity principle in terms of better transfer. However, this coincided with a large increase in time-on-task. Also, large individual differences existed in the use of learner control options, which were mostly unrelated to the other variables. Thus, the benefits of introducing learner control in multimedia learning are at the expense of learning efficiency, and it remains unclear for whom the interactivity principle works best

    07 CESARI_04 LORD_c

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    Abstract: Sarcopenia, the age-related skeletal muscle decline, is associated with relevant clinical and socioeconomic negative outcomes in older persons. The study of this phenomenon and the development of preventive/therapeutic strategies represent public health priorities. The present document reports the results of a recent meeting of the International Working Group on Sarcopenia (a task force consisting of geriatricians and scientists from academia and industry) held on June 7-8, 2011 in Toulouse (France). The meeting was specifically focused at gaining knowledge on the currently available biomarkers (functional, biological, or imaging-related) that could be utilized in clinical trials of sarcopenia and considered the most reliable and promising to evaluate age-related modifications of skeletal muscle. Specific recommendations about the assessment of aging skeletal muscle in older people and the optimal methodological design of studies on sarcopenia were also discussed and finalized. Although the study of skeletal muscle decline is still in a very preliminary phase, the potential great benefits derived from a better understanding and treatment of this condition should encourage research on sarcopenia. However, the reasonable uncertainties (derived from exploring a novel field and the exponential acceleration of scientific progress) require the adoption of a cautious and comprehensive approach to the subject
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