541 research outputs found

    Making if-then plans counteracts learned non-use in stroke patients: A proof-of-principle study

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    Background: After stroke, the learned non-use of a paretic arm is a major obstacle to the improvement of hand function. / Objective: We examined whether patients with a central paresis could profit from applying the self-regulation strategy of making if-then plans that specify situational triggers to using the paretic arm. / Method: Seventeen stroke patients with a mild to moderate hand paresis were asked to perform a Simon task which is commonly used to study the enhanced executive control needed when there is a mismatch between stimulus (e.g., color) and response (e.g., location) features. We examined whether patients with hemiparesis would be able to reduce the Simon effect (i.e., responding slower to mismatched as compared to matched stimulus and response features) by creating new stimulus-response associations via if-then plans. / Results: A significant Simon effect was observed in both the affected and the non-affected arm for control trials. However, there was no longer a significant Simon effect for the critical trials prepared by forming if-then plans. This led to a significant stimulusĂ—compatibility interaction effect for the affected arm and a marginally significant interaction effect for the nonaffected arm. Making if-then plans was effective for eliminating or at least reducing the Simon effect for the affected and the non-affected arm, respectively. / Conclusion: This observation opens a potential new route to improving stroke rehabilitation. If-then plans may qualify as a viable strategy to overcome the learned non-use of the affected arm. Further research is now required to develop and test therapeutic measures based on this proof-of-principle

    Ultrasonic particle sizing in aqueous suspensions of solid particles of unknown density

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    Estimates of particle size distributions (PSDs) in solid-in-liquid suspensions can be made on the basis of measurements of ultrasonic wave attenuation combined with a mathematical propagation model, which typically requires seven physical parameters to describe each phase of the mixture. The estimation process is insensitive to all of these except the density of the solid particles, which may not be known or difficult to measure. This paper proposes that an unknown density value is incorporated into the sizing computation as a free variable. It is shown that this leads to an accurate estimate of PSD, as well as the unknown density

    Formation mechanism of a nano ring of bismuth cations and mono-lacunary Keggin-type phosphomolybdate

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    A new hetero-bimetallic polyoxometalate (POM) nano ring was synthesized in a one-pot procedure. The structure consists of tetrameric units containing four bismuth-substituted monolacunary Keggin anions including distorted [BiO8] cubes. The nano ring is formed via self -assembly from metal precursors in aqueous acidic medium. The compound (NH4)16[(BiPMo11O39)4]Ă—22H2O; (P4Bi4Mo44) was characterized by single-crystal X-ray diffraction, extended X-ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF), and thermogravimetry/differential scanning calorimetry (TG-DSC-MS). The formation of the nano ring in solution was studied by time-resolved in situ small- and wide-angle X-ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo-K and the Bi-L3 edge indicating a two-step process consisting of condensation of Mo-anions and formation of Bi-Mo-units followed by a rapid self-assembly to yield the final tetrameric ring structure

    MR-IMPACT: comparison of perfusion-cardiac magnetic resonance with single-photon emission computed tomography for the detection of coronary artery disease in a multicentre, multivendor, randomized trial

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    Aims To determine in a multicentre, multivendor trial the diagnostic performance for perfusion-cardiac magnetic resonance (perfusion-CMR) in comparison with coronary X-ray angiography (CXA) and single-photon emission computed tomography (SPECT). Methods and results Of 241 eligible patients from 18 centres, 234 were randomly dosed with 0.01, 0.025, 0.05, 0.075, or 0.1 mmol/kg Gd-DTPA-BMA (Omniscan™, GE-Healthcare) per stress (0.42 mg/kg adenosine) and rest perfusion study. Coronary artery disease (CAD) was defined as diameter stenosis ≥50% on quantitative CXA. Five CMR and eight SPECT studies (of 225 complete studies) were excluded from analyses due to inadequate quality (three blinded readers scored per modality). The comparison of CMR vs. SPECT was based on receiver operating characteristic (ROC) analysis. Perfusion-CMR at the optimal CM dose (0.1 mmol/kg) had similar performance as SPECT, if only the SPECT studies of the 42 patients with this dose were considered [area under ROC curve (AUC): 0.86 ± 0.06 vs. 0.75 ± 0.09 for SPECT, P = 0.12]; however, diagnostic performance of perfusion-CMR was better vs. the entire SPECT population (AUC: 0.67 ± 0.05, n = 212, P = 0.013). Conclusions In this multicentre, multivendor trial, ROC analyses suggest perfusion-CMR as a valuable alternative to SPECT for CAD detection showing equal performance in the head-to-head comparison. Comparing perfusion-CMR with the entire SPECT population suggests CMR superiority over SPECT, which warrants further evaluation in larger trial

    Unique transcriptional and protein-expression signature in human lung tissue-resident NK cells

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    Human lung tissue-resident NK cells (trNK cells) are likely to play an important role in host responses towards viral infections, inflammatory conditions and cancer. However, detailed insights into these cells are still largely lacking. Here we show, using RNA sequencing and flow cytometry-based analyses, that subsets of human lung CD69(-)CD16(-) NK cells display hallmarks of tissue-residency, including high expression of CD49a, CD103, and ZNF683, and reduced expression of SELL, S1PR5, and KLF2/3. CD49a(+)CD16(-) NK cells are functionally competent, and produce IFN-gamma, TNF, MIP-1 beta, and GM-CSF. After stimulation with IL-15, they upregulate perforin, granzyme B, and Ki67 to a similar degree as CD49a(-) CD16(-) NK cells. Comparing datasets from trNK cells in human lung and bone marrow with tissue-resident memory CD8(+) T cells identifies core genes co-regulated either by tissue-residency, cell-type or location. Together, our data indicate that human lung trNK cells have distinct features, likely regulating their function in barrier immunity.Peer reviewe

    Circuit Quantum Electrodynamics: Coherent Coupling of a Single Photon to a Cooper Pair Box

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    Under appropriate conditions, superconducting electronic circuits behave quantum mechanically, with properties that can be designed and controlled at will. We have realized an experiment in which a superconducting two-level system, playing the role of an artificial atom, is strongly coupled to a single photon stored in an on-chip cavity. We show that the atom-photon coupling in this circuit can be made strong enough for coherent effects to dominate over dissipation, even in a solid state environment. This new regime of matter light interaction in a circuit can be exploited for quantum information processing and quantum communication. It may also lead to new approaches for single photon generation and detection.Comment: 8 pages, 4 figures, accepted for publication in Nature, embargo does apply, version with high resolution figures available at: http://www.eng.yale.edu/rslab/Andreas/content/science/PubsPapers.htm

    First-Principles Semiclassical Initial Value Representation Molecular Dynamics

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    A method for carrying out semiclassical initial value representation calculations using first-principles molecular dynamics (FP-SC-IVR) is presented. This method can extract the full vibrational power spectrum of carbon dioxide from a single trajectory providing numerical results that agree with experiment even for Fermi resonant states. The computational demands of the method are comparable to those of classical single-trajectory calculations, while describing uniquely quantum features such as the zero-point energy and Fermi resonances. By propagating the nuclear degrees of freedom using first-principles Born-Oppenheimer molecular dynamics, the stability of the method presented is improved considerably when compared to dynamics carried out using fitted potential energy surfaces and numerical derivatives.Comment: 5 pages, 2 figures, made stylistic and clarity change

    Neural predictive control of broiler chicken and pig growth

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    Active control of the growth of broiler chickens and pigs has potential benefits for farmers in terms of improved production efficiency, as well as for animal welfare in terms of improved leg health in broiler chickens. In this work, a differential recurrent neural network (DRNN) was identified from experimental data to represent animal growth using a nonlinear system identification algorithm. The DRNN model was then used as the internal model for nonlinear model predictive control (NMPC) to achieve a group of desired growth curves. The experimental results demonstrated that the DRNN model captured the underlying dynamics of the broiler and pig growth process reasonably well. The DRNN based NMPC was able to specify feed intakes in real time so that the broiler and pig weights accurately followed the desired growth curves ranging from to +12% and to +20% of the standard curve for broiler chickens and pigs, respectively. The overall mean relative error between the desired and achieved broiler or pig weight was 1.8% for the period from day 12 to day 51 and 10.5% for the period from week 5 to week 21, respectively
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