Tag: pubmed

Phys Rev Lett. 2026 Jul 10;137(2):024001. doi: 10.1103/fj29-8l44.

ABSTRACT

Velocity circulation around closed loops is a fundamental quantity of central interest in the study of the energy cascade in turbulent flows. Recent theoretical and numerical studies have identified circulation as a geometric observable that captures intermittency through the area rule and a distinctive bifractal scaling of its moments in classical and quantum turbulence. One fundamental question is how these statistical characteristics of circulation are altered when an additional agent such as long-chain flexible polymer that can modify the turbulence energy cascade is added to the fluid. Here, through stereo particle image velocimetry measurements in high Reynolds number (R_{λ}≈393) turbulent flow of pure water and dilute polymer solution in a von Kármán swirling flow system, we provide the first experimental evidence that the area rule and the bifractality of the circulation hold for planar loops in both the 3D Newtonian and polymeric turbulence. These two statistical characteristics of circulation are robust despite strong modifications of the energy cascade and small-scale topology induced by polymer elasticity, except that the Hölder exponent in polymeric turbulence (h≈1.55) is significantly larger than in Newtonian turbulence (h≈1.14), suggesting that the flow is smoother in polymeric turbulence. Our results establish velocity circulation as a more universal and fundamental tool, compared to the very frequently used velocity increments, for unifying intermittency across different turbulent systems from Newtonian to polymeric to quantum turbulence.

PMID:42503133 | DOI:10.1103/fj29-8l44

Phys Rev Lett. 2026 Jul 10;137(2):026101. doi: 10.1103/2mrn-lhmz.

ABSTRACT

Chemical short-range order (SRO) is an intrinsic feature of the atomic structures in multiprincipal element alloys (MPEAs). Effective control of SRO structures could considerably improve the strength and ductility of MPEAs. However, the experimental characterization of SRO remains highly challenging due to their extremely high complexity and small sizes. This Letter presents that, by integrating experiments and atomistic modeling, positron annihilation spectroscopy could directly identify SRO structures in bcc NbTiZr MPEA. It was revealed that both Zr-rich and Nb-rich regions are formed in the SRO structure. The effects of lattice relaxation and electron charges lead to an increased positron annihilation contribution from Zr and a corresponding decrease from Nb. This subtle change was directly captured by integrating theoretical and experimental positron annihilation Doppler broadening spectra. The evolution of SRO was further validated by synchrotron small angle x-ray scattering. Unlike conventional localized techniques, the proposed approach provides a nondestructive, statistically averaged and element-sensitive probe, establishing a unique route to identify local chemical fluctuations in complex materials.

PMID:42503116 | DOI:10.1103/2mrn-lhmz

Phys Rev Lett. 2026 Jul 10;137(2):026301. doi: 10.1103/6qcc-wdtx.

ABSTRACT

The fluctuation-dissipation theorem connects equilibrium noise to linear response and forms a cornerstone of statistical and quantum physics, yet its extension to geometry-driven nonlinear transport remains largely unexplored. Here we establish a geometric fluctuation-dissipation relation linking dc current noise at linear order to second-order nonlinear responses-specifically shift and injection photocurrents-in the bulk photovoltaic effect of noncentrosymmetric gapped quantum materials. Using a microscopic density-matrix formalism, we show that linear dc current noise in the dc electric field arising from off-diagonal current correlations is universally governed by frequency-integrated nonlinear optical responses and is encoded in the quantum geometry of Bloch states. We further demonstrate that intrinsic and extrinsic noise contributions exhibit distinct symmetry properties and relaxation-time dependencies, corresponding respectively to shift and injection photocurrents. We derive analytical expressions in a generic two-band model and numerically verify them in the Haldane model. Our results establish dc current noise at linear order as a direct probe of quantum geometry and nonlinear optical response in gapped quantum materials, extending fluctuation-dissipation relations well beyond linear equilibrium transport.

PMID:42503114 | DOI:10.1103/6qcc-wdtx

Phys Rev Lett. 2026 Jul 10;137(2):021902. doi: 10.1103/dmv6-7gdv.

ABSTRACT

The first observation of the doubly charmed baryon Ξ_{cc}^{+} is reported through its decay to the Λ_{c}^{+}K^{-}π^{+} final state, with a statistical significance exceeding seven standard deviations. The observation is made using proton-proton collision data collected in 2024 with the LHCb Run 3 detector at a center-of-mass energy of 13.6 TeV, corresponding to a total integrated luminosity of 6.9 fb^{-1}. The Ξ_{cc}^{+} mass is measured to be 3619.97±0.83±0.26_{-1.30}^{+1.90} MeV/c^{2}, where the first uncertainty is statistical, the second is systematic, and the third is due to the unknown Ξ_{cc}^{+} lifetime, which is assumed to lie in the range 15-160 fs with a baseline value of 45 fs. The difference between the masses of the Ξ_{cc}^{+} and Ξ_{cc}^{++} baryons is determined to be -1.77±0.84±0.15_{-1.30}^{+1.90} MeV/c^{2}. This is the first observation of a new particle made with the LHCb Run 3 detector.

PMID:42503113 | DOI:10.1103/dmv6-7gdv

Phys Rev Lett. 2026 Jul 10;137(2):026703. doi: 10.1103/jn9y-yfcw.

ABSTRACT

We address a central open question in driven topological matter by investigating the nonequilibrium response of a two-dimensional magnet with Dzyaloshinskii-Moriya interactions subjected to a periodically oscillating magnetic field. Using extensive Monte Carlo simulations, we uncover a dynamically reentrant skyrmion phase that emerges within a finite window of field amplitudes and bias fields, sandwiched between the conventional skyrmion and polarized ferromagnetic phases. This phase has no equilibrium counterpart and originates from an imbalance between skyrmion creation and annihilation over a single field cycle, leading to a reversal of the period-averaged topological charge. We show that the reentrant phase exists only in the dynamic response regime where the system can follow the drive, and is suppressed at higher driving frequencies. Our results establish periodic driving as a nonequilibrium control parameter for stabilizing and reversing skyrmion topology.

PMID:42503084 | DOI:10.1103/jn9y-yfcw

Phys Rev Lett. 2026 Jul 10;137(2):020201. doi: 10.1103/xdcg-6df5.

ABSTRACT

Continuous-variable quantum systems are foundational to quantum computation, communication, and sensing. While traditional representations using wave functions or density matrices are often impractical, the tomographic picture of quantum mechanics provides an accessible alternative by associating quantum states with classical probability distribution functions called tomograms. Despite its advantages, including compatibility with classical statistical methods, the tomographic method remains underutilized due to a lack of robust estimation techniques. This Letter addresses this gap by introducing a nonparametric kernel quantum state estimation (KQSE) framework for reconstructing quantum states and their trace characteristics from noisy data, without prior knowledge of the state. In contrast to existing methods, KQSE yields estimates of the density matrix in various bases, as well as trace quantities such as purity, higher moments, overlap, and trace distance, with a near-optimal convergence rate of O[over ˜](T^{-1}), where T is the total number of measurements. KQSE is robust for multimodal, non-Gaussian states, making it particularly well suited for characterizing states essential for quantum science.

PMID:42503078 | DOI:10.1103/xdcg-6df5

Phys Rev Lett. 2026 Jul 10;137(2):020403. doi: 10.1103/v8x8-ft81.

ABSTRACT

We analyze the effects of various forms of noise on one-dimensional systems of noninteracting fermions. In the strong noise limit, we demonstrate, under mild assumptions, that the statistics of the fermionic correlation matrix in the thermodynamic limit follow a universal form described by the recently introduced quantum simple symmetric exclusion process (QSSEP). For charge transport, we show that QSSEP, along with all models in its universality class, shares the same large deviation function for the transferred charge as the classical SSEP model. The method we introduce to derive this result relies on a gaugelike invariance associated with the choice of the bond where the current is measured. This approach enables the explicit calculation of the cumulant-generating function for both QSSEP and SSEP and establishes an exact correspondence between them. These analytical findings are validated by extensive numerical simulations. Our results establish that a wide range of noisy free-fermionic models share the same QSSEP universality class and show that their transport properties are essentially classical.

PMID:42503077 | DOI:10.1103/v8x8-ft81

World J Urol. 2026 Jul 26;44(1):519. doi: 10.1007/s00345-026-06636-2.

ABSTRACT

BACKGROUND: The relationship between the triglyceride-glucose index (TyG) and the risk of kidney stone formation has not been fully explored in the current literature. Although an association between the TyG index, associated indices, and kidney stone formation has been reported, this link remains unconfirmed. Clarifying this relationship is crucial for both individual health and public health decision-making. Additionally, the TyG index and its related indices are gaining recognition for their emerging utility as valuable biomarkers in epidemiological studies of kidney stones.

OBJECTIVE: The main objective of this research is to assess the correlation between the TyG index, associated indices, and the prevalence of kidney stones. Furthermore, we seek to investigate the potential broader implications of this association for public health policy and clinical practice.

METHODS: We conducted a cross-sectional study involving a representative sample of 12,159 participants from the US population. For data analysis, logistic regression combined with smooth curve fitting techniques was employed to precisely evaluate the relationship between the TyG index and kidney stone prevalence. The predictive capability of TyG and its derived indices for kidney stone risk was comprehensively assessed using AUC, NRI, and IDI. To examine the robustness of our findings under different assumptions, we conducted a sensitivity analysis.

RESULTS: The overall prevalence of kidney stone disease was 9.9%, comprising 54.84% of males and 45.16% of females. Compared with the group without a history of kidney stones, the group with a history of kidney stones exhibited significantly elevated triglyceride-glucose indices and related indicators. In the fully adjusted model, compared with the first tertile (T1) group, the risk of developing kidney stones increased in the third tertile (T3) group, with odds ratios (ORs) and 95% confidence intervals (CI) of TyG was 1.23 (0.99-1.54), triglyceride glucose-waist circumference (TyG-WC) was 1.93 (1.55-2.41), triglyceride glucose-body mass index (TyG-BMI) was 1.87 (1.51-2.31), triglyceride glucose-waist to height ratio (TyG-WHtR) was 1.66 (1.31-2.11), triglyceride glucose-weight-adjusted waist index (TyG-WWI) was 1.57 (1.23-2.00), and triglyceride glucose-a body shape index (TyG -ABSI) was 1.29 (1.04-1.60) respectively. Restricted cubic spline (RCS) analysis indicated that kidney stones’ risk increased with rising TyG and its derived indices. Subsequent subgroup analyses revealed no significant interactions in most subgroups (all P > 0.05). Results from the three sensitivity analyses aligned with those of the primary analysis, reinforcing its robustness.

CONCLUSIONS: Our investigation revealed that TyG and its derived indices had a significant link to the prevalence of kidney stones in the US adult population. Future research could involve designing and conducting longitudinal or cohort studies to validate further associations and possibilities.

PMID:42503069 | DOI:10.1007/s00345-026-06636-2

Clin Drug Investig. 2026 Jul 26. doi: 10.1007/s40261-026-01580-w. Online ahead of print.

ABSTRACT

BACKGROUND AND OBJECTIVES: Viloxazine (extended-release [ER] capsules) is a nonstimulant medication approved for the treatment of pediatric (aged ≥ 6 years) and adult attention deficit hyperactivity disorder. This study assessed the effect of hepatic impairment (HI) on the pharmacokinetics, safety, and tolerability of viloxazine ER.

METHODS: In this open-label, multicenter study, adults (18-78 years) with mild (n = 8), moderate (n = 8), or severe (n = 8) HI (Child-Pugh classification) and a demographically matched control cohort with normal hepatic function received a single oral dose of viloxazine ER (200 or 400 mg), following a ≥ 10-h overnight fast. Blood samples were collected for 72 h post-administration and analyzed for viloxazine and its primary metabolite 5-hydroxy-viloxazine glucuronide. The potential for HI to impact pharmacokinetics was evaluated using relative bioavailability analysis of viloxazine maximum measured plasma concentration (C_max) and area under the concentration-time curve (AUC) parameters and comparison of time to C_max (T_max) and terminal elimination half-life (t_1/2). Safety and tolerability were also evaluated.

RESULTS: In adults with versus without HI (any severity), there were no significant differences in viloxazine C_max (mean ± standard deviation [SD] for mild HI, 3.1 ± 1.0 µg/mL versus 2.4 ± 0.4 µg/mL; moderate HI, 2.5 ± 0.8 µg/mL versus 2.5 ± 0.6 µg/mL; severe HI, 1.3 ± 0.4 µg/mL versus 1.5 ± 0.2 µg/mL) and AUC (from time 0 to infinity; mean ± SD for mild HI, 70.5 ± 19.3 h·µg/mL versus 56.8 ± 8.6 h·µg/mL; moderate HI, 62.8 ± 28.9 h·µg/mL versus 60.4 ± 20.5 h·µg/mL; severe HI, 42.0 ± 16.4 h·µg/mL versus 33.1 ± 9.7 h·µg/mL), and mean exposure for those with HI was within 25% of matched control values. Increased t_1/2 was observed in moderate and severe HI versus controls (mean ± SD for mild HI, 7.6 ± 3.1 h versus 6.7 ± 2.5 h; moderate HI, 9.3 ± 3.1 h versus 6.0 ± 1.7 h; severe HI, 14.2 ± 5.8 h versus 7.1 ± 2.7 h). No adverse event (AE) was reported by ≥ 2 study participants with HI. The most common AEs were headache (n = 1 mild HI, n = 2 healthy controls) and somnolence (n = 2 healthy controls).

CONCLUSIONS: Mild-to-severe HI showed minimal impact on viloxazine ER exposure. The single dose of viloxazine ER was well-tolerated with no identified safety concerns.

PMID:42503060 | DOI:10.1007/s40261-026-01580-w

Clin Transl Oncol. 2026 Jul 26. doi: 10.1007/s12094-026-04498-z. Online ahead of print.

ABSTRACT

PURPOSE: To explore whether adjuvant immunotherapy can improve postoperative prognosis for non-small cell lung cancer (NSCLC) patients harboring oncogenic driver alterations beyond EGFR and ALK, a population with unclear benefit.

METHODS: Main inclusion criteria included resected NSCLC, stage IB-IIIB, and oncogenic driver alterations of KRAS mutation, ROS1 fusion, RET fusion, HER2 mutation, NTRK fusion, BRAF V600E mutation, and MET exon 14 skipping mutation. The positive PD-L1 cut-off was 1%. Adjuvant immunotherapy would be administered for one year or up to 16 cycles. Disease-free survival (DFS) after surgery was the endpoint.

RESULTS: 190 patients with specific gene alterations were included, 25.8% of patients received adjuvant immunotherapy. The benefit from adjuvant immunotherapy in DFS was not observed in the overall population (hazard ratio [HR] 0.85, 95% confidence interval [CI 0.51-1.44, p = 0.551), while a numerical DFS benefit trend in the PD-L1-positive population was observed (HR 0.56, 95% CI 0.31-1.03, p = 0.059). After inverse probability of treatment weighting (IPTW) for the population with PD-L1 positivity who also received adjuvant chemotherapy, no statistical DFS benefit difference from adjuvant immunotherapy was observed between the KRAS (HR 0.29, 95% CI 0.10-0.88, p = 0.028) and non-KRAS mutation (HR 0.77, 95% CI 0.32-1.82, p = 0.549) subgroups (interaction p = 0.179), though with a marked numerical difference. Among the PD-L1-positive population, NSCLC harboring KRAS, MET exon 14 skipping, and BRAF V600E mutations showed a trend toward benefit from adjuvant immunotherapy, whereas NSCLC with HER2 mutation, RET fusion, and ROS1 fusion exhibited a weaker trend toward benefit.

CONCLUSIONS: Patients with NSCLC harboring driver oncogenes other than EGFR/ALK and positive PD-L1 showed a trend toward benefiting from adjuvant immunotherapy. Although no significant interaction was observed, KRAS-mutant NSCLC demonstrated numerically superior DFS benefit compared with non-KRAS-mutant NSCLC.

PMID:42503059 | DOI:10.1007/s12094-026-04498-z