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Nevin Manimala Statistics

Epidemiology and anatomical distribution of stress fractures in children and adolescents: an 8-year retrospective study

J Orthop Surg Res. 2026 Mar 1. doi: 10.1186/s13018-026-06768-6. Online ahead of print.

ABSTRACT

OBJECTIVE: This study aimed to investigate the epidemiological characteristics and anatomical distribution of stress fractures (SFs) in a pediatric and adolescent population over an eight-year period.

METHODS: We conducted a retrospective cohort study at a tertiary care orthopedic center. We reviewed medical records and imaging data for patients aged 6-18 years who were diagnosed with SFs between January 2017 and December 2024. Patients were assigned to age groups of 6-11, 12-15, and 16-18 years. We collected demographic data, fracture location, and annual consultation-based rates. Statistical analyses were performed using SPSS 26.0 and R software for trend analysis.

RESULTS: A total of 726 patients (403 males, 323 females; median age 14 years, IQR 12-15) were included. The overall consultation-based rate was 23.20 per 100,000 unique pediatric orthopedic patients. Cases were concentrated in the 12-15 years age group, which accounted for 78.24%. The tibia was the most commonly involved bone (83.06%), and the proximal tibia was the single most frequent site (48.62%). Annual rates rose from 8.09 per 100,000 in 2017 to a peak of 38.98 in 2022, then declined to 23.98 in 2024(Poisson regression for linear trend, P < 0.001). Male patients had a higher proportion of proximal tibia fractures, whereas female patients had more mid- to distal-tibia fractures (P < 0.01).

CONCLUSIONS: SFs predominantly affected adolescent males, and the proximal tibia was the most vulnerable site. The observed rise-and-fall trend temporally coincided with shifts in educational and physical activity policies in China, although causal inference was limited by the ecological study design. These descriptive findings emphasized the need for prospective studies that incorporate exposure and risk-factor assessment to inform targeted prevention strategies.

PMID:41765889 | DOI:10.1186/s13018-026-06768-6

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Nevin Manimala Statistics

First Observation of the B[over ¯]_{s}^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Decay and Evidence for the B[over ¯]^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Decay

Phys Rev Lett. 2026 Feb 13;136(6):061802. doi: 10.1103/cxn3-8t4g.

ABSTRACT

A search is presented for the two-body charmed baryonic decays, B[over ¯]_{(s)}^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-}, using a data sample collected by the LHCb experiment during 2011-2012 and 2015-2018, corresponding to an integrated luminosity of 9 fb^{-1}. The first observation of the B[over ¯]_{s}^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} decay is reported with 6.2σ significance along with 4.3σ evidence for the B[over ¯]^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} decay. The branching fractions are measured to be B(B[over ¯]^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-})=(1.01_{-0.28}^{+0.27}±0.08±0.15)×10^{-5} and B(B[over ¯]_{s}^{0}→Λ_{c}^{+}Λ[over ¯]_{c}^{-})=(5.0±1.3±0.5±0.8)×10^{-5}, where the first uncertainty is statistical, the second systematic, and the third due to external inputs. These results provide novel experimental inputs for the theoretical framework describing two-body baryonic decays of B mesons via W-emission and W-exchange mechanisms.

PMID:41765847 | DOI:10.1103/cxn3-8t4g

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Nevin Manimala Statistics

Bosonization of Noise Effects in Nonlocal Quantum Dynamics

Phys Rev Lett. 2026 Feb 13;136(6):060402. doi: 10.1103/ls2g-mkhm.

ABSTRACT

Quantum systems that interact nonlocally with an environment are paradigms for exploring collective phenomena. They naturally emerge in various physical contexts involving long-range, many-body interactions. We consider a general class of such open systems characterized by a coupling to the environment that is inversely proportional to the square root of the environment size. We show that the induced system dynamics has a universal bosonic nature: the same evolution arises from coupling the system to a collection of noninteracting bosonic modes, independently of the microscopic structure of the original environment. This emergent “bosonization” of the environment’s influence results from the scaling of the coupling in the thermodynamic limit and is a manifestation of the quantum central limit theorem. While the effect has been observed in specific models before, we show that it is, in fact, a universal feature.

PMID:41765846 | DOI:10.1103/ls2g-mkhm

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Nevin Manimala Statistics

Rate Equation for the Transfer of Interstitials across Interfaces between Equilibrated Crystals

Phys Rev Lett. 2026 Feb 13;136(6):066201. doi: 10.1103/kfpq-9dd1.

ABSTRACT

This Letter inspects the thermally activated transfer of solute particles across the interface between two interstitial solid solution phases that equilibrate internally by fast diffusion on conserved arrays of sites. When each phase is considered as an ergodic ensemble of particles, statistical mechanics predicts the occupancy of the transition states at equilibrium to depend on the barrier energy and on the chemical potentials and vacancy fractions in each of the phases. A rate law for the nonequilibrium interfacial transfer, based on a constant transition probability between activated states, naturally satisfies the principle of detailed balance. Contrary to Butler-Volmer-type laws, values of the particle chemical potentials enter explicitly rather than through their differences. This, along with the dependency on the vacancy fractions, implies here an exchange flux density that depends explicitly on the compositions at equilibrium. The results can explain experimental observations of a drastic slowdown in the charging of metal hydrides near phase transformations or miscibility-gap critical points.

PMID:41765843 | DOI:10.1103/kfpq-9dd1

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Nevin Manimala Statistics

Analytical and AI-Discovered Stable, Accurate, and Generalizable Subgrid-Scale Closure for Geophysical Turbulence

Phys Rev Lett. 2026 Feb 13;136(6):064201. doi: 10.1103/v28b-5qmp.

ABSTRACT

By combining artificial intelligence and fluid physics, we discover a closed-form closure for 2D turbulence from small direct numerical simulation data. Large-eddy simulation with this closure is accurate and stable, reproducing direct numerical simulation statistics, including those of extremes. We also show that the new closure could be derived from a fourth-order truncated Taylor expansion. Prior analytical and artificial-intelligence-based work only found the second-order expansion, which led to unstable large-eddy simulation. The additional terms emerge only when interscale energy transfer is considered alongside standard reconstruction criterion in the sparse-equation discovery.

PMID:41765828 | DOI:10.1103/v28b-5qmp

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Nevin Manimala Statistics

Macroscopic Fluctuation-Response Theory and Its Use for Gene Regulatory Networks

Phys Rev Lett. 2026 Feb 13;136(6):067102. doi: 10.1103/2b12-3vrx.

ABSTRACT

Gaussian macroscopic fluctuation theory underpins the understanding of noise in a broad class of nonequilibrium systems. We derive exact fluctuation-response relations linking the power spectral density of stationary fluctuations to the linear response of stable nonequilibrium steady states. Both of these can be determined experimentally and used to reconstruct the kernel of the linearized dynamics and the diffusion matrix, and thus any features of the Gaussian theory. We apply our theory to gene regulatory networks with negative feedback, and derive an explicit internal-external noise decomposition of the power spectral density for any networks, including cross-correlations.

PMID:41765826 | DOI:10.1103/2b12-3vrx

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Nevin Manimala Statistics

Gibbs Measures from Deep Shaped Multilayer Perceptrons

Phys Rev Lett. 2026 Feb 13;136(6):067301. doi: 10.1103/xm8d-v66z.

ABSTRACT

We develop a diagrammatic approach analyzing Gibbs measures (i.e., Bayesian posteriors) in deep shaped multilayer perceptrons at arbitrary temperature. This gives the first (perturbatively) solvable model of learning with nonlinear neural networks where the input dimension N_{0}, depth L, width N, and number of samples P can all be large without severe assumptions on either initialization or training data statistics. The limits N_{0},N,L,P→∞ do not commute, resulting in a rich phase diagram of learning regimes that we study to first order in 1/N. We find in particular that the ratio LP/N defines a critical depth necessary for feature learning: if LP/N→0, then Bayesian posteriors coincide with those of a kernel method. Regimes where LP/N→λ>0, in contrast, correspond to learning with data-dependent deformations of these kernels, and we provide explicit formulas for the resulting features to first order in 1/N.

PMID:41765812 | DOI:10.1103/xm8d-v66z

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Nevin Manimala Statistics

Isotope Shift Spectroscopy in Mercury Vapors: A Promising Alternative to Ytterbium for New Physics Search

Phys Rev Lett. 2026 Feb 13;136(6):063001. doi: 10.1103/2qxw-y8df.

ABSTRACT

Isotope shift metrology in the deep-UV region has been performed for all bosonic isotopes of mercury with a zero nuclear spin, using the technique of frequency-comb referenced, wavelength-modulated, saturated absorption spectroscopy. The absolute center frequencies of the 6s^{2} ^{1}S_{0}→6s6p ^{3}P_{1} transition have been measured with precision in the range of 2.5-5.9 10^{-12} in temperature-stabilized Hg vapor samples with natural abundances. Frequency shifts in four isotope pairs have been determined with unprecedented accuracy, the global uncertainty being improved by a factor greater than 20 with respect to the best experimental data of the past literature. Our dataset, when combined with previous measurements on the 6s6p ^{3}P_{2}→6s7s ^{3}S_{1} transition at 546 nm, allows us to build a King plot that reveals a nonlinearity with a statistical significance of 4.6σ.

PMID:41765806 | DOI:10.1103/2qxw-y8df

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Nevin Manimala Statistics

Diffusive and Enzymatic Modulation of the Dynamic Size Distribution of DNA Droplets

Phys Rev Lett. 2026 Feb 13;136(6):068403. doi: 10.1103/x2pf-n27q.

ABSTRACT

We investigate how material diffusion processes affect the temporal evolution of the radii of DNA droplets formed from DNA nanoparticles whose phase-separation ability can be enzymatically degraded. The droplets are immobilized so as to disallow Brownian coalescence, and their size is tracked using confocal fluorescent microscopy. Without enzymes, we observe very slow Ostwald ripening in rough agreement with the Lifshitz-Slyozov-Wagner theory. With enzymes, we observe a dynamic radius distribution in which time and radius decouple, leading to an unusual behavior in which the average radius remains constant despite the total droplet volume decreasing. Our Letter provides insights into the statistical dynamics of phase-separated droplets, with relevance to both biological condensates and materials applications.

PMID:41765797 | DOI:10.1103/x2pf-n27q

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Nevin Manimala Statistics

Comparative prosthetic outcomes of two bar attachment systems in mandibular two-implant overdentures: A 5-year pilot study

J Prosthodont. 2026 Mar 1. doi: 10.1111/jopr.70115. Online ahead of print.

ABSTRACT

PURPOSE: Mandibular two-implant overdentures represent the standard of care for edentulous patients; however, long-term evidence comparing prosthetic maintenance demands among different bar attachment systems remains limited. This pilot randomized clinical study aimed to compare the 5-year prosthetic complications and maintenance profiles of bar-locator versus bar-clip attachments to inform clinical attachment selection.

MATERIALS AND METHODS: Sixteen completely edentulous patients were rehabilitated with new maxillary and mandibular complete dentures and received two implants placed in the mandibular canine regions. Participants were randomly allocated to either a bar-locator group (n = 8) or a bar-clip group (n = 8). Prosthetic complications, including retentive component wear, screw loosening, tooth wear, denture fracture, relining, and other maintenance events, were clinically recorded over a 5-year follow-up period.

RESULTS: All participants completed the 5-year follow-up (100% retention). A total of 24 prosthetic complications were recorded in the bar-locator group and 13 in the bar-clip group. The mean number of complications per patient was 3.0 ± 1.3 for bar-locator and 1.6 ± 0.9 for bar-clip overdentures (absolute risk difference = +1.4; 95% CI: -0.3 to 3.0). Although the bar-locator group demonstrated numerically higher frequencies of retentive insert wear, tooth wear, and minor fractures, none of the between-group differences reached statistical significance (p > 0.05). No catastrophic mechanical failures were observed in either group.

CONCLUSIONS: Over 5 years, both bar-locator and bar-clip attachment systems demonstrated reliable mechanical performance and clinical longevity. The bar-locator system was associated with a higher overall maintenance burden. In contrast, bar-clip overdentures required relining more frequently, reflecting distinct long-term maintenance profiles rather than differences in durability. These pilot findings support the feasibility of a larger randomized trial and highlight the need for future studies incorporating patient-reported outcomes, cost-effectiveness analyses, and time-to-event assessments of prosthetic maintenance.

PMID:41765771 | DOI:10.1111/jopr.70115