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A large qubit capacity and an individual readout capability are two crucial requirements for large-scale quantum computing and simulation 1 . As one of the leading physical platforms for quantum information processing, the ion trap has achieved a quantum simulation of tens of ions with site-resolved readout in a one-dimensional Paul trap 2 – 4 and of hundreds of ions with global observables in a two-dimensional (2D) Penning trap 5 , 6 . However, integrating these two features into a single system is still very challenging. Here we report the stable trapping of 512 ions in a 2D Wigner crystal and the sideband cooling of their transverse motion. We demonstrate the quantum simulation of long-range quantum Ising models with tunable coupling strengths and patterns, with or without frustration, using 300 ions. Enabled by the site resolution in the single-shot measurement, we observe rich spatial correlation patterns in the quasi-adiabatically prepared ground states, which allows us to verify quantum simulation results by comparing the measured two-spin correlations with the calculated collective phonon modes and with classical simulated annealing. We further probe the quench dynamics of the Ising model in a transverse field to demonstrate quantum sampling tasks. Our work paves the way for simulating classically intractable quantum dynamics and for running noisy intermediate-scale quantum algorithms 7 , 8 using 2D ion trap quantum simulators. In this work, stable trapping of a two-dimensional Wigner crystal of above 500 ions is achieved, and the quantum simulation of 300 ions with individual state detection demonstrated.

Two-dimensional (2D) ion crystals may represent a promising path to scale up qubit numbers for ion trap quantum information processing. However, to realize universal quantum computing in this system, individually addressed high-fidelity two-qubit entangling gates still remain challenging due to the inevitable micromotion of ions in a 2D crystal as well as the technical difficulty in 2D addressing. Here we demonstrate two-qubit entangling gates between any ion pairs in a 2D crystal of four ions. We use symmetrically placed crossed acousto-optic deflectors (AODs) to drive Raman transitions and achieve an addressing crosstalk error below 0.1%. We design and demonstrate a gate sequence by alternatingly addressing two target ions, making it compatible with any single-ion addressing techniques without crosstalk from multiple addressing beams. We further examine the gate performance versus the micromotion amplitude of the ions and show that its effect can be compensated by a recalibration of the laser intensity without degrading the gate fidelity. Our work paves the way for ion trap quantum computing with hundreds to thousands of qubits on a 2D ion crystal. Quantum gates in 2D ion crystals are more challenging than in 1D. Here, the authors use their 2D ion trap platform and acousto-optical deflectors to demonstrate a 2-qubit gate that can stand the ion micromotion in such configuration.

We consider the fidelity of the vector meson dominance (VMD) assumption as an instrument for relating the electromagnetic vector-meson production reaction e+p→e′+V+p to the purely hadronic process V+p→V+p. Analyses of the photon vacuum polarisation and the photon-quark vertex reveal that such a VMD Ansatz might be reasonable for light vector-mesons. However, when the vector-mesons are described by momentum-dependent bound-state amplitudes, VMD fails for heavy vector-mesons: it cannot be used reliably to estimate either a photon-to-vector-meson transition strength or the momentum dependence of those integrands that would arise in calculations of the different reaction amplitudes. Consequently, for processes involving heavy mesons, the veracity of both cross-section estimates and conclusions based on the VMD assumption should be reviewed, e.g., those relating to hidden-charm pentaquark production and the origin of the proton mass.

The effectiveness of using a balloon guide catheter during endovascular thrombectomy in patients with acute ischaemic stroke due to large vessel occlusion of the anterior circulation remains uncertain. We aimed to assess the effectiveness and safety of using a balloon guide catheter during endovascular thrombectomy, compared with using a conventional guide catheter, in this patient population. We conducted a multicentre, open-label, blinded-endpoint, randomised controlled trial at 28 hospitals in China. Adults aged 18 years or older with acute ischaemic stroke who were able to receive endovascular thrombectomy within 24 h after symptom onset, according to local guidelines, were eligible. Patients were randomly assigned (1:1) to the balloon guide catheter group or the conventional guide catheter group using a central internet-based system with a minimisation algorithm. The treating physicians and patients were aware of treatment allocation, but clinical outcomes were collected by local trained physicians who were masked. Neurological assessments were performed at baseline, 24 h after randomisation, and at 7 days or hospital discharge (whichever occurred first). The primary outcome was functional recovery, assessed by change in modified Rankin Scale (mRS) scores (ranging from 0 [no symptoms] to 6 [death]) at 90 days in the intention-to-treat population and obtained from structured interviews. Treatment effect was estimated using ordinal logistic regression with adjustment for site and baseline prognostic factors (time from symptom onset to randomisation, the preferred thrombectomy strategy, baseline National Institutes of Health Stroke Scale score, prestroke function [estimated mRS score], and age). This trial is registered with ClinicalTrials.gov, NCT05592054 (terminated). Between Feb 7 and Nov 13, 2023, 1698 patients were assessed for eligibility and 329 were randomly assigned to the balloon guide catheter group (n=164) or conventional guide catheter group (n=165) when the trial was paused and subsequently terminated on April 18, 2024, due to safety concerns. The median age was 69 years (IQR 59–76). Of 329 patients, 201 (61%) were male and 128 (39%) were female. Participants in the balloon guide catheter group had significantly worse scores on the mRS at 90 days than those in the conventional guide catheter group (adjusted common odds ratio 0·66 [95% CI 0·45–0·98]; p=0·037). All-cause mortality at 90 days was numerically higher in the balloon guide catheter group than in the conventional guide catheter group (39 [24%] vs 26 [16%]). There were no statistically significant differences between groups in intracranial haemorrhage, symptomatic intracranial haemorrhage, or other serious adverse events. Compared with conventional guide catheters, the use of balloon guide catheters led to worse functional recovery in patients receiving endovascular thrombectomy for intracranial large vessel occlusion. Future studies are needed to confirm these results. National Natural Science Foundation of China, Shanghai Hospital Development Center, Biopharma Industry Promotion Center Shanghai, and Ton-bridge Medical Technology. For the Chinese translation of the abstract see Supplementary Materials section.

Sarcopenia is an age-related disease, which is characterized by a decline in muscle mass and function. It is one of the most important health issues in the elderly and often leads to a high rate and variety of adverse outcomes. To evaluate the screening accuracy of SARC-F for sarcopenia in the elderly. We conducted a meta-analysis using articles available in 6 databases including PubMed (Medline), Web of Science, Embase, Cochrane Controlled Register of Trials (CENTRAL), China Knowledge Resource Integrated Database (CNKI), and Wanfang databases from inception to May 2020. Participants: Adults aged 60 years and older. Sarcopenia was defined by EWGSOP2, EWGSOP, AWGS, FNIH and IWGS. Two authors independently extracted data based on predefined criteria. Where data were available we calculated pooled summary estimates of sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and their 95% confidence interval (CI) based on different criteria using the hierarchical logistic regression modeling including bivariate modeling and hierarchical summary receiver operating characteristic (HSROC) modeling. We included 20 studies, with the prevalence of sarcopenia ranging from 6.42% to 21.56%. The number of the literatures using EWGSOP, EWGSOP2, AWGS, IWGS and FNIH as diagnostic criteria was 13, 4, 13, 8, 7, respectively. Bivariate analysis yielded a pooled sensitivity of 32% (95%CI: 19%–47%), 77% (95%CI: 49%–92%), 27% (95%CI: 16%–42%), 39% (95%CI: 27%–52%), 35% (95%CI: 23%–49%) and a pooled specificity of 86% (95%CI:77%–92%), 63% (95%CI: 43%–79%), 91% (95%CI: 85%–95%), 86% (95%CI: 76%–92%), 89% (95%CI: 81%–93%), respectively. The area under the HSROC curve were 0.68 (95%CI: 0.64–0.72), 0.75 (95%CI: 0.71–0.78), 0.73 (95%CI: 0.69–0.77), 0.67 (95%CI: 0.62–0.71), 0.70 (95%CI: 0.65–0.73), respectively. The screening accuracy of SARC-F was various based on different diagnostic criteria. There were some limitations for SARC-F, however, considering the higher practicability and specificity for screening sarcopenia in practice, SARC-F was still an effective screening tool for sarcopenia in the elderly. And the screening accuracy of SARC-F needs further exploration when EWGSOP2 is applied as diagnostic criteria and geriatric inpatients are the target participants.

The heterogeneous breast cancers can be classified into different subtypes according to their histopathological characteristics and molecular signatures. Foxa1 expression is linked with luminal breast cancer (LBC) with good prognosis, whereas Twist1 expression is associated with basal-like breast cancer (BLBC) with poor prognosis owing to its role in promoting epithelial-to-mesenchymal transition (EMT), invasiveness and metastasis. However, the regulatory and functional relationships between Twist1 and Foxa1 in breast cancer progression are unknown. In this study, we demonstrate that in the estrogen receptor (ERα)-positive LBC cells Twist1 silences Foxa1 expression, which has an essential role in relieving Foxa1-arrested migration, invasion and metastasis of breast cancer cells. Mechanistically, Twist1 binds to Foxa1 proximal promoter and recruits the NuRD transcriptional repressor complex to de-acetylate H3K9 and repress RNA polymerase II recruitment. Twist1 also silences Foxa1 promoter by inhibiting AP-1 recruitment. Twist1 expression in MCF7 cells silenced Foxa1 expression, which was concurrent with the induction of EMT, migration, invasion and metastasis of these cells. Importantly, restored Foxa1 expression in these cells largely inhibited Twist1-promoted migration, invasion and metastasis. Restored Foxa1 expression did not change the Twist1-induced mesenchymal cellular morphology and the expression of Twist1-regulated E-cadherin, β-catenin, vimentin and Slug, but it partially rescued Twist1-silenced ERα and cytokeratin 8 expression and reduced Twist1-induced integrin α5, integrin β1 and MMP9 expression. In a xenografted mouse model, restored Foxa1 also increased Twist1-repressed LBC markers and decreased Twist1-induced BLBC markers. Furthermore, Twist1 expression is negatively correlated with Foxa1 in the human breast tumors. The tumors with high Twist1 and low Foxa1 expressions are associated with poor distant metastasis-free survival. These results demonstrate that Twist1’s silencing effect on Foxa1 expression is largely responsible for Twist1-induced migration, invasion and metastasis, but less responsible for Twist1-induced mesenchymal morphogenesis and expression of certain EMT markers.

The super τ-charm facility (STCF) is an electron−positron collider proposed by the Chinese particle physics community. It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5 × 10 35 cm −2·s −1 or higher. The STCF will produce a data sample about a factor of 100 larger than that of the present τ-charm factory - the BEPCII, providing a unique platform for exploring the asymmetry of matter-antimatter (charge-parity violation), in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions, as well as searching for exotic hadrons and physics beyond the Standard Model. The STCF project in China is under development with an extensive R&D program. This document presents the physics opportunities at the STCF, describes conceptual designs of the STCF detector system, and discusses future plans for detector R&D and physics case studies.

Background/Objectives: Studies suggest that the Mediterranean-style diet (MSD) may improve glucose metabolism in patients with type 2 diabetes (T2D), but the results are inconsistent. We conducted a meta-analysis of randomized controlled trials (RCTs) to explore the effects of MSD on glycemic control, weight loss and cardiovascular risk factors in T2D patients. Subjects/Methods: We performed searches of EMBASE, Cochrane Library and PubMed databases up to February 2014. We included RCTs that compared the MSD with control diets in patients with T2D. Effect size was estimated as mean difference with 95% confidence interval (CI) by using random effect models. Results: The meta-analysis included nine studies with 1178 patients. Compared with control diets, MSD led to greater reductions in hemoglobin A1c (mean difference, −0.30; 95% CI, −0.46 to −0.14), fasting plasma glucose (−0.72 mmol/l; CI, −1.24 to −0.21), fasting insulin (−0.55 μU/ml; CI, −0.81 to −0.29), body mass index (−0.29 kg/m 2 ; CI, −0.46 to −0.12) and body weight (−0.29 kg; CI, −0.55 to −0.04). Likewise, concentrations of total cholesterol and triglyceride were decreased (−0.14 mmol/l; CI, −0.19 to −0.09 and −0.29 mmol/l; CI, −0.47 to −0.10, respectively), and high-density lipoprotein was increased (0.06 mmol/l; CI, 0.02 to 0.10). In addition, MSD was associated with a decline of 1.45 mm Hg (CI, −1.97 to −0.94) for systolic blood pressure and 1.41 mm Hg (CI, −1.84 to −0.97) for diastolic blood pressure. Conclusions: The present meta-analysis provides evidence that MSD improves outcomes of glycemic control, body weight and cardiovascular risk factors in T2D patients.

The discovery of high-temperature superconductivity in iron pnictides raised the possibility of an unconventional superconducting mechanism in multiband materials. The observation of Fermi-surface (FS)-dependent nodeless superconducting gaps suggested that inter-FS interactions may play a crucial role in superconducting pairing. In the optimally hole-doped Ba₀.₆K₀.₄Fe₂As₂, the pairing strength is enhanced simultaneously (2Δ/Tc[almost equal to]7) on the nearly nested FS pockets, i.e., the inner hole-like (α) FS and the 2 hybridized electron-like FSs, whereas the pairing remains weak (2Δ/Tc[almost equal to]3.6) in the poorly nested outer hole-like (β) FS. Here, we report that in the electron-doped BaFe₁.₈₅Co₀.₁₅As₂, the FS nesting condition switches from the α to the β FS due to the opposite size changes for hole- and electron-like FSs upon electron doping. The strong pairing strength (2Δ/Tc[almost equal to]6) is also found to switch to the nested β FS, indicating an intimate connection between FS nesting and superconducting pairing, and strongly supporting the inter-FS pairing mechanism in the iron-based superconductors.

Two-mode interferometers lay the foundations for quantum metrology. Instead of exploring quantum entanglement in the two-mode interferometers, a single bosonic mode also promises a measurement precision beyond the shot-noise limit (SNL) by taking advantage of the infinite-dimensional Hilbert space of Fock states. Here, we demonstrate a single-mode phase estimation that approaches the Heisenberg limit (HL) unconditionally. Due to the strong dispersive nonlinearity and long coherence time of a microwave cavity, quantum states of the form 0 + N ∕ 2 can be generated, manipulated and detected with high fidelities, leading to an experimental phase estimation precision scaling as ∼ N −0.94 . A 9.1 dB enhancement of the precision over the SNL at N  = 12 is achieved, which is only 1.7 dB away from the HL. Our experimental architecture is hardware efficient and can be combined with quantum error correction techniques to fight against decoherence, and thus promises quantum-enhanced sensing in practical applications. Reaching a quantum advantage in metrology usually requires hard-to-prepare two-mode entangled states such as NOON states. Here, instead, the authors demonstrate single-mode phase estimation using Fock states superpositions in a superconducting qubit-oscillator system.