Cyclic nonlinear interferometry with entangled non-Gaussian spin states

We propose an efficient nonlinear readout scheme for entangled non-Gaussian spin states (ENGSs) based on the intrinsic quasi-cyclic dynamics of interacting spin-1/2 systems. We focus on two well-known spin models of twist-and-turn (TNT) and two-axis-counter-twisting (TACT), where ENGS can be generated by spin dynamics starting from unstable fixed points. In the TNT model, non-Gaussian probe state evolves directly back to the vicinity of initial state during the subsequent time-forward evolution for path recombining, accompanied by quantum magnification of encoded signal and refocusing of the associated quantum noise. Based on low-order moment measurement, we find the optimal metrological gain nearly saturates the quantum Cramer-Rao bound (QCRB) and follows the Heisenberg scaling. For the TACT case, the QCRB can also be nearly approached when the state converges to either of the two unstable fixed points, respectively corresponding to the initial state or its orthogonal coherent state. The latter case goes beyond previous studies where tracing back to or crossing the initial states is mostly considered. The present protocol does not require time-reversal as in typical nonlinear interferometries, and it also avoids complicated measurement of nonlinear observables or full probability distributions. The operational approach we discuss presents a practical way for realizing high-precision and detection-noise-robust quantum metrology with ENGS.Comment: 10 pages, 6 figure

Benefits and risks of antihypertensive medication in adults with different systolic blood pressure: A meta-analysis from the perspective of the number needed to treat

BackgroundThe blood pressure (BP) threshold for initial pharmacological treatment remains controversial. The number needed to treat (NNT) is a significant indicator. This study aimed to explore the benefits and risks of antihypertensive medications in participants with different systolic BPs (SBPs), and cardiovascular disease status from the perspective of the NNT.MethodsWe conducted a meta-analysis of 52 randomized placebo-controlled trials. The data were extracted from published articles and pooled to calculate NNTs. The participants were divided into five groups, based on the mean SBP at entry (120–129.9, 130–139.9, 140–159.9, 160–179.9, and ≥180 mmHg). Furthermore, we stratified patients into those with and without cardiovascular disease. The primary outcomes were the major adverse cardiovascular events (MACEs), and adverse events (AEs) leading to discontinuation.ResultsAntihypertensive medications were not associated with MACEs, however, it increased AEs, when the SBP was <140 mmHg. For participants with cardiovascular disease or at a high risk of heart failure and stroke, antihypertensive treatment reduced MACEs when SBP was ≥130 mmHg. Despite this, only 2–4 subjects had reduced MACEs per 100 patients receiving antihypertensive medications for 3.50 years. The number of individuals who needed to treat to avoid MACEs declined with an increased cardiovascular risk.ConclusionPharmacological treatment could be activated when SBP reaches 140 mmHg. For people with cardiovascular disease or at a higher risk of stroke and heart failure, 130 mmHg may be a better therapeutic threshold. It could be more cost-effective to prioritize antihypertensive medications for people with a high risk of developing cardiovascular disease

Effects of different starch sources on Bacillus spp. in intestinal tract and expression of intestinal development related genes of weanling piglets

The study was conducted to evaluate the effects of different starch sources on Bacillus spp. in intestinal tract and expression of intestinal development related genes of weanling piglets. Twenty-eight PIC male piglets were divided into four homogeneous groups according to initial body weight (similar birth and parity, weaned at 21 ± 1.5 days). Diets for the four treatments consisted of corn starch, wheat starch, tapioca starch and pea starch with the determined ratio for amylose to amylopectin of 0.21, 0.24, 0.12 and 0.52 respectively. Real-time quantitative polymerase chain reaction was applied to: (1) detect genomic DNA of Bacillus and to quantify the number of Bacillus in the intestinal tract chyme of piglets with the primers and probe which designed based on the 16S rRNA sequences of maximum species of Bacillus on GenBank; (2) measure the mRNA level of glucagon-like peptide 2 (GLP-2), insulin-like growth factors 1 (IGF-1) and epidermal growth factor (EGF) in duodenum, jejunum and ileum. Results showed that the number of Baciilus and the percentage based on all bacteria in the whole intestinal content of piglets fed pea starch was highest in all groups (P < 0.05). There was no significant differance on copy numbers for all bacteria and Bacillus in the whole intestinal tract of piglets between the corn starch group and wheat starch group (P > 0.05). In addition, the expression level of GLP-2, IGF-1 mRNA in jejunum and ileum of pea starch treatment (the high amylose/amylopectin ratio) were increased while the tapioca starch decreased their mRNA level significantly compared to other three treatments (P < 0.05). There was no significant difference for the mRNA level of EGF in each group. The present study revealed that high amylose/amylopectin ratio of starches significantly enhanced the numbers of Bacillus in all segments of intestine and the mRNA level of intestinal development related genes

Detection of entangled states supported by reinforcement learning

Discrimination of entangled states is an important element of quantum enhanced metrology. This typically requires low-noise detection technology. Such a challenge can be circumvented by introducing nonlinear readout process. Traditionally, this is realized by reversing the very dynamics that generates the entangled state, which requires a full control over the system evolution. In this work, we present nonlinear readout of highly entangled states by employing reinforcement learning (RL) to manipulate the spin-mixing dynamics in a spin-1 atomic condensate. The RL found results in driving the system towards an unstable fixed point, whereby the (to be sensed) phase perturbation is amplified by the subsequent spin-mixing dynamics. Working with a condensate of 10900 {87}^Rb atoms, we achieve a metrological gain of 6.97 dB beyond the classical precision limit. Our work would open up new possibilities in unlocking the full potential of entanglement caused quantum enhancement in experiments

Dmbg-Net: Dilated multiresidual boundary guidance network for COVID-19 infection segmentation

Accurate segmentation of infected regions in lung computed tomography (CT) images is essential for the detection and diagnosis of coronavirus disease 2019 (COVID-19). However, lung lesion segmentation has some challenges, such as obscure boundaries, low contrast and scattered infection areas. In this paper, the dilated multiresidual boundary guidance network (Dmbg-Net) is proposed for COVID-19 infection segmentation in CT images of the lungs. This method focuses on semantic relationship modelling and boundary detail guidance. First, to effectively minimize the loss of significant features, a dilated residual block is substituted for a convolutional operation, and dilated convolutions are employed to expand the receptive field of the convolution kernel. Second, an edge-attention guidance preservation block is designed to incorporate boundary guidance of low-level features into feature integration, which is conducive to extracting the boundaries of the region of interest. Third, the various depths of features are used to generate the final prediction, and the utilization of a progressive multi-scale supervision strategy facilitates enhanced representations and highly accurate saliency maps. The proposed method is used to analyze COVID-19 datasets, and the experimental results reveal that the proposed method has a Dice similarity coefficient of 85.6% and a sensitivity of 84.2%. Extensive experimental results and ablation studies have shown the effectiveness of Dmbg-Net. Therefore, the proposed method has a potential application in the detection, labeling and segmentation of other lesion areas

Skepticism and Euroskepticism in British Politics

This article provides an analysis of the variants of Euroskepticism voiced in the British political discourse on furthering integration of the United Kingdom with Europe