Tag: statistics

Phys Rev Lett. 2024 Feb 2;132(5):050202. doi: 10.1103/PhysRevLett.132.050202.

ABSTRACT

A well-motivated method for demonstrating that an experiment resists any classical explanation is to show that its statistics violate generalized noncontextuality. We here formulate this problem as a linear program and provide an open-source implementation of it which tests whether or not any given prepare-measure experiment is classically explainable in this sense. The input to the program is simply an arbitrary set of quantum states and an arbitrary set of quantum effects; the program then determines if the Born rule statistics generated by all pairs of these can be explained by a classical (noncontextual) model. If a classical model exists, it provides an explicit model. If it does not, then it computes the minimal amount of noise that must be added such that a model does exist, and then provides this model. We generalize all these results to arbitrary generalized probabilistic theories (and accessible fragments thereof) as well; indeed, our linear program is a test of simplex embeddability as introduced in Schmid et al. [PRX Quantum 2, 010331 (2021).2691-339910.1103/PRXQuantum.2.010331] and generalized in Selby et al. [Phys. Rev. A 107, 062203 (2023).PLRAAN2469-992610.1103/PhysRevA.107.062203].

PMID:38364156 | DOI:10.1103/PhysRevLett.132.050202

Phys Rev Lett. 2024 Feb 2;132(5):057102. doi: 10.1103/PhysRevLett.132.057102.

ABSTRACT

The force autocorrelation function (FACF), a concept of fundamental interest in statistical mechanics, encodes the effect of interactions on the dynamics of a tagged particle. In equilibrium, the FACF is believed to decay monotonically in time, which is a signature of slowing down of the dynamics of the tagged particle due to interactions. Here, we analytically show that in odd-diffusive systems, which are characterized by a diffusion tensor with antisymmetric elements, the FACF can become negative and even exhibit temporal oscillations. We also demonstrate that, despite the isotropy, the knowledge of FACF alone is not sufficient to describe the dynamics: the full autocorrelation tensor is required and contains an antisymmetric part. These unusual properties translate into enhanced dynamics of the tagged particle quantified via the self-diffusion coefficient that, remarkably, increases due to particle interactions.

PMID:38364150 | DOI:10.1103/PhysRevLett.132.057102

Phys Rev Lett. 2024 Feb 2;132(5):050203. doi: 10.1103/PhysRevLett.132.050203.

ABSTRACT

Distillation, or purification, is central to the practical use of quantum resources in noisy settings often encountered in quantum communication and computation. Conventionally, distillation requires using some restricted “free” operations to convert a noisy state into one that approximates a desired pure state. Here, we propose to relax this setting by only requiring the approximation of the measurement statistics of a target pure state, which allows for additional classical postprocessing of the measurement outcomes. We show that this extended scenario, which we call “virtual resource distillation,” provides considerable advantages over standard notions of distillation, allowing for the purification of noisy states from which no resources can be distilled conventionally. We show that general states can be virtually distilled with a cost (measurement overhead) that is inversely proportional to the amount of existing resource, and we develop methods to efficiently estimate such cost via convex and semidefinite programming, giving several computable bounds. We consider applications to coherence, entanglement, and magic distillation, and an explicit example in quantum teleportation (distributed quantum computing). This work opens a new avenue for investigating generalized ways to manipulate quantum resources.

PMID:38364147 | DOI:10.1103/PhysRevLett.132.050203

Phys Rev Lett. 2024 Feb 2;132(5):051802. doi: 10.1103/PhysRevLett.132.051802.

ABSTRACT

The decay-time-dependent CP asymmetry in B_{s}^{0}→J/ψ(→μ^{+}μ^{-})K^{+}K^{-} decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 6 fb^{-1}, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349 000 B_{s}^{0} signal decays with an invariant K^{+}K^{-} mass in the vicinity of the ϕ(1020) resonance, the CP-violating phase ϕ_{s} is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B_{s}^{0}-B[over ¯]_{s}^{0} system, ΔΓ_{s}, and the difference of the average B_{s}^{0} and B^{0} meson decay widths, Γ_{s}-Γ_{d}. The values obtained are ϕ_{s}=-0.039±0.022±0.006 rad, ΔΓ_{s}=0.0845±0.0044±0.0024 ps^{-1}, and Γ_{s}-Γ_{d}=-0.0056_{-0.0015}^{+0.0013}±0.0014 ps^{-1}, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements to date and are consistent with expectations based on the Standard Model and with the previous LHCb analyses of this decay. These results are combined with previous independent LHCb measurements. The phase ϕ_{s} is also measured independently for each polarization state of the K^{+}K^{-} system and shows no evidence for polarization dependence.

PMID:38364143 | DOI:10.1103/PhysRevLett.132.051802

Phys Rev Lett. 2024 Feb 2;132(5):057001. doi: 10.1103/PhysRevLett.132.057001.

ABSTRACT

We study the interplay between Coulomb blockade and superconductivity in a tunable superconductor-superconductor-normal-metal single-electron transistor. The device is realized by connecting the superconducting island via an oxide barrier to the normal-metal lead and with a break junction to the superconducting lead. The latter enables Cooper pair transport and (multiple) Andreev reflection. We show that these processes are relevant also far above the superconducting gap and that signatures of Coulomb blockade may reoccur at high bias while they are absent for small bias in the strong-coupling regime. Our experimental findings agree with simulations using a rate equation approach in combination with the full counting statistics of multiple Andreev reflection.

PMID:38364128 | DOI:10.1103/PhysRevLett.132.057001

J Dev Behav Pediatr. 2024 Jan 1;45(1):e46-e53. doi: 10.1097/DBP.0000000000001232.

ABSTRACT

OBJECTIVE: Determine the risk of autoimmune disease in research-identified cases of autism spectrum disorder (ASD) compared with referents using a longitudinal, population-based birth cohort.

METHODS: ASD incident cases were identified from a population-based birth cohort of 31,220 individuals. Inclusive ASD definition based on DSM-IV-TR autistic disorder, Asperger syndrome, and pervasive developmental disorder, not otherwise specified, was used to determine ASD cases. For each ASD case, 2 age- and sex-matched referents without ASD were identified. Diagnosis codes assigned between birth and December 2017 were electronically obtained. Individuals were classified as having an autoimmune disorder if they had at least 2 diagnosis codes more than 30 days apart. Cox proportional hazards models were fit to estimate the hazard ratio (HR) between ASD status and autoimmune disorder.

RESULTS: Of 1014 ASD cases, 747 (73.7%) were male. Fifty ASD cases and 59 of the 1:2 matched referents were diagnosed with first autoimmune disorder at the median age of 14 and 17.1 years, respectively. ASD cases had increased risk of autoimmune disease compared with matched referents (HR 1.74; 95% confidence interval [CI], 1.21-2.52). The increased risk was statistically significant among male patients (HR 2.01; 95% CI, 1.26-3.21) but not among the smaller number of female subjects (HR 1.38; 95% CI, 0.76-2.50).

CONCLUSION: This study provides evidence from a longitudinal, population-based birth cohort for co-occurrence of ASD and autoimmune disorders. Thus, children with ASD should be monitored for symptoms of autoimmune disease and appropriate workup initiated.

PMID:38364086 | DOI:10.1097/DBP.0000000000001232

J Acoust Soc Am. 2024 Feb 1;155(2):1451-1468. doi: 10.1121/10.0024890.

ABSTRACT

Theoretical accounts posit a close link between speech perception and production, but empirical findings on this relationship are mixed. To explain this apparent contradiction, a proposed view is that a perception-production relationship should be established through the use of critical perceptual cues. This study examines this view by using Mandarin tones as a test case because the perceptual cues for Mandarin tones consist of perceptually critical pitch direction and noncritical pitch height cues. The defining features of critical and noncritical perceptual cues and the perception-production relationship of each cue for each tone were investigated. The perceptual stimuli in the perception experiment were created by varying one critical and one noncritical perceptual cue orthogonally. The cues for tones produced by the same group of native Mandarin participants were measured. This study found that the critical status of perceptual cues primarily influenced within-category and between-category perception for nearly all tones. Using cross-domain bidirectional statistical modelling, a perception-production link was found for the critical perceptual cue only. A stronger link was obtained when within-category and between-category perception data were included in the models as compared to using between-category perception data alone, suggesting a phonetically and phonologically driven perception-production relationship.

PMID:38364045 | DOI:10.1121/10.0024890

Eur J Emerg Med. 2024 Feb 16. doi: 10.1097/MEJ.0000000000001128. Online ahead of print.

ABSTRACT

BACKGROUND: Whether high-flow nasal oxygen can improve clinical signs of acute respiratory failure in acute heart failure (AHF) is uncertain.

OBJECTIVE: To compare the effect of high-flow oxygen with noninvasive ventilation (NIV) on respiratory rate in patients admitted to an emergency department (ED) for AHF-related acute respiratory failure.

DESIGN, SETTINGS AND PARTICIPANTS: Multicenter, randomized pilot study in three French EDs. Adult patients with acute respiratory failure due to suspected AHF were included. Key exclusion criteria were urgent need for intubation, Glasgow Coma Scale <13 points or hemodynamic instability.

INTERVENTION: Patients were randomly assigned to receive high-flow oxygen (minimum 50 l/min) or noninvasive bilevel positive pressure ventilation.

OUTCOMES MEASURE: The primary outcome was change in respiratory rate within the first hour of treatment and was analyzed with a linear mixed model. Secondary outcomes included changes in pulse oximetry, heart rate, blood pressure, blood gas samples, comfort, treatment failure and mortality.

MAIN RESULTS: Among the 145 eligible patients in the three participating centers, 60 patients were included in the analysis [median age 86 (interquartile range (IQR), 90; 92) years]. There was a median respiratory rate of 30.5 (IQR, 28; 33) and 29.5 (IQR, 27; 35) breaths/min in the high-flow oxygen and NIV groups respectively, with a median change of -10 (IQR, -12; -8) with high-flow nasal oxygen and -7 (IQR, -11; -5) breaths/min with NIV [estimated difference -2.6 breaths/min (95% confidence interval (CI), -0.5-5.7), P = 0.052] at 60 min. There was a median SpO2 of 95 (IQR, 92; 97) and 96 (IQR, 93; 97) in the high-flow oxygen and NIV groups respectively, with a median change at 60 min of 2 (IQR, 0; 5) with high-flow nasal oxygen and 2 (IQR, -1; 5) % with NIV [estimated difference 0.8% (95% CI, -1.1-2.8), P = 0.60]. PaO2, PaCO2 and pH did not differ at 1 h between groups, nor did treatment failure, intubation and mortality rates.

CONCLUSION: In this pilot study, we did not observe a statistically significant difference in changes in respiratory rate among patients with acute respiratory failure due to AHF and managed with high-flow oxygen or NIV. However, the point estimate and its large confidence interval may suggest a benefit of high-flow oxygen.

TRIAL REGISTRATION: NCT04971213 (https://clinicaltrials.gov).

PMID:38364020 | DOI:10.1097/MEJ.0000000000001128

J Chem Phys. 2024 Feb 21;160(7):074106. doi: 10.1063/5.0185580.

ABSTRACT

The terminal alkyne C≡C stretch has a large Raman scattering cross section in the “silent” region for biomolecules. This has led to many Raman tag and probe studies using this moiety to study biomolecular systems. A computational investigation of these systems is vital to aid in the interpretation of these results. In this work, we develop a method for computing terminal alkyne vibrational frequencies and isotropic transition polarizabilities that can easily and accurately be applied to any terminal alkyne molecule. We apply the discrete variable representation method to a localized version of the C≡C stretch normal mode. The errors of (1) vibrational localization to the terminal alkyne moiety, (2) anharmonic normal mode isolation, and (3) discretization of the Born-Oppenheimer potential energy surface are quantified and found to be generally small and cancel each other. This results in a method with low error compared to other anharmonic vibrational methods like second-order vibrational perturbation theory and to experiments. Several density functionals are tested using the method, and TPSS-D3, an inexpensive nonempirical density functional with dispersion corrections, is found to perform surprisingly well. Diffuse basis functions are found to be important for the accuracy of computed frequencies. Finally, the computation of vibrational properties like isotropic transition polarizabilities and the universality of the localized normal mode for terminal alkynes are demonstrated.

PMID:38364010 | DOI:10.1063/5.0185580

Holist Nurs Pract. 2024 Mar-Apr 01;38(2):93-101. doi: 10.1097/HNP.0000000000000633.

ABSTRACT

Midlife women often experience menopausal symptoms despite being treated according to clinical guidelines. The consequences of not addressing menopausal symptoms holistically are that 55% of women see primary care providers frequently with menopausal symptom complaints. The problem was women’s lack of coping strategies to deal with their symptoms effectively. The interventions aimed to (1) develop a protocol to provide point-of-care mindfulness-based meditation intervention as a standard of care, (2) evaluate improvements in coping self-efficacy skills, and (3) demonstrate the intervention’s impact on menopausal symptoms. Twenty women participated in a short meditation intervention at a micro practice in Oregon from January to May 2022 and continued an 8-week home practice. Self-reported measures of menopausal symptoms, coping self-efficacy, and demographic data were collected pre- and pos-tprogram. A percentage of women determined improvements, and t tests evaluated differences between pre-and postintervention assessments. Pearson correlation coefficients identified associations between the Menopausal Rating Scale (MRS), its subscales, and the Coping Self-Efficacy Scale (CSES) postintervention. The women showed 78% improved coping self-efficacy and 89% alleviated menopausal symptoms. The t test revealed a statistically significant change between pre- and post-CSES scores (t17 = 4.19, P < .001) and MRS scores (t17 = 4.78, P < .001). The post-MRS total score was significantly negatively correlated with the post-CSES score (r = -0.49, P = .039), indicating that symptoms decreased as self-efficacy improved. The outcomes of this project show that menopausal women can cope and alleviate their symptoms with an easy and feasible mindfulness-based meditation intervention.

PMID:38363970 | DOI:10.1097/HNP.0000000000000633