Tag: pubmed

J Neurosurg Pediatr. 2026 Jul 31:1-6. doi: 10.3171/2026.3.PEDS25681. Online ahead of print.

ABSTRACT

OBJECTIVE: It is unclear whether shunt survival differs for infants in whom prior endoscopic third ventriculostomy with choroid plexus cauterization (ETV/CPC) failed compared with those treated initially by shunt placement. Results among four previous studies spanning a range of age groups have suggested either no effect or a protective effect of prior endoscopic treatment on shunt survival. The aim of this study was to determine whether prior ETV/CPC positively impacts shunt survival among infants with hydrocephalus regardless of etiology.

METHODS: The authors conducted a historical cohort review of all patients under 12 months corrected age who underwent ventriculoperitoneal shunt (VPS) placement either with or without prior ETV/CPC at their institution between December 2008 and December 2023. Statistical analyses included Cox regression modeling, Kaplan-Meier survival curves, and log-rank testing to evaluate the time to shunt failure.

RESULTS: The study included 122 infants with and 46 infants without prior ETV/CPC who underwent VPS placement. There were no statistically significant differences between groups regarding sex, race, gestational age at birth, or corrected age at initial treatment for hydrocephalus. The distribution of etiologies and initial frontal-occipital horn ratios (FOHRs) were similar. The median pre-shunt FOHR was greater in the ETV/CPC group. The patients in the primary shunt placement group were all candidates for ETV/CPC based on retrospective review. Seventy-one infants (58%) with prior ETV/CPC remained free of shunt revision compared with 17 infants (37%) with primary shunt placement (OR 2.4, 95% CI 1.1-5.1; p = 0.01). The estimated 2-year shunt survival probability was 75% with and 50% without prior ETV/CPC (log-rank p = 0.001). The estimated 5-year survival was 60% with and 45% without prior ETV/CPC (p = 0.045).

CONCLUSIONS: Infants who underwent ETV/CPC prior to VPS placement had better shunt survival than those who did not. ETV/CPC might reduce the risk of subsequent shunt failure, indicating the potential benefit of the procedure even when it fails.

PMID:42537233 | DOI:10.3171/2026.3.PEDS25681

JMIR Med Inform. 2026 Jul 31;14:e88854. doi: 10.2196/88854.

ABSTRACT

BACKGROUND: Online health care consultation provides patients with broad access to physicians, but also presents the challenge of selecting a suitable doctor in the absence of triage guidance. Patients have multifaceted needs, prioritizing not only recommendation accuracy but also physician service quality, and diversity of physician expertise. Furthermore, the sparsity of patient interaction data intensifies the difficulty of providing balanced and effective recommendations.

OBJECTIVE: This study aims to develop a multiobjective physician recommendation method that simultaneously optimizes recommendation accuracy, service quality, and diversity of physician expertise while addressing the data sparsity challenge inherent in online health care platforms.

METHODS: We propose dynamic graph-based bacteria colony optimization for multiobjective physician recommendation (DyGMO-PR), a dynamic graph-based multiobjective optimization method. It integrates bacterial colony optimization with an evolving physician relationship graph. Our approach features a novel graph-based encoding scheme, a chemotaxis-inspired graph-walking strategy for stable search, and a dynamic graph evolution mechanism that learns implicit physician relationships to enhance recommendation quality under sparse data conditions.

RESULTS: Evaluation on a real-world dataset comprising 10,493 consultation records from 1256 patients and 1377 physicians demonstrates the effectiveness of DyGMO-PR. Our method consistently outperforms 6 state-of-the-art multiobjective recommendation algorithms. Using a recommendation list length of 6 as an example, DyGMO-PR achieves an accuracy of 0.876, a service quality of 0.873, and a diversity of 0.720, surpassing the best-performing baseline by 7.4%, 3.1%, and 8.1%, respectively. DyGMO-PR also attains the highest hypervolume value (0.696 at K=6) and the highest recall (0.380 at K=6). Case studies and graph analysis further demonstrate the method’s effectiveness in generating interpretable and balanced recommendation lists.

CONCLUSIONS: DyGMO-PR offers an effective solution for multiobjective physician recommendation. It provides a flexible and practical foundation for building more responsive and reliable recommender systems in online health care.

PMID:42537221 | DOI:10.2196/88854

JMIR Mhealth Uhealth. 2026 Jul 31;14:e48828. doi: 10.2196/48828.

ABSTRACT

BACKGROUND: Many frameworks and tools are available to evaluate the quality of mobile health apps (MHAs), which are increasingly used by health care professionals (HCPs) for accessing medical information, clinical decision support, and communication. However, existing tools are not well equipped to assess the quality of apps designed for HCPs from their perspectives.

OBJECTIVE: We aimed to develop a new tool based on the Mobile App Rating Scale (MARS) to capture the unique perspectives of HCPs on MHAs. We then conducted a psychometric analysis of this new questionnaire to determine its effectiveness in assessing the quality of MHAs designed specifically for HCPs from their perspectives.

METHODS: This study was conducted in 2 phases. In phase 1, the original MARS tool was adapted for HCPs through expert panel review and subsequent qualitative interviews, resulting in the development of the pMARS (MARS for health care professionals) tool. This phase focused on establishing face and content validity. Qualitative interviews were conducted with HCPs from a tertiary hospital in Singapore to gather their perspectives on the tool’s structure, clarity, applicability, and usability. In phase 2, we invited HCP participants to complete pMARS based on their experience with the LabMed app, an mHealth tool designed to provide medical laboratory-related information to HCPs. We established the construct validity of pMARS through multiple psychometric techniques. Internal consistency reliability was measured using the Cronbach α, while structural equation modeling was used to examine the interrelationships among latent constructs. Additionally, we used item response theory (IRT) to evaluate each item’s impact on latent constructs of interest, that is, discriminative performance of individual items within each domain.

RESULTS: Based on the results from phase 1, the pMARS comprised 26 items across 5 domains: engagement, functionality, aesthetics, information, and subjective quality, refined through interviews with 10 HCPs. In phase 2 (n=218), pMARS demonstrated good internal consistency reliability across all domains (Cronbach α=0.855-0.931). Structural equation modeling demonstrated that functionality had the strongest influence on end-user willingness to use, recommend, and purchase the MHA (P<.001). IRT identified that customization and interactivity of the engagement domain had a weak impact on latent constructs, whereas entertainment had a higher impact. Ease of use and gestural design had a weak impact on the functionality domain, whereas arrangement and size of content and quantity and quality had a strong impact on the aesthetics and information domains, respectively.

CONCLUSIONS: This study reports the development and psychometric analysis of pMARS. Our findings demonstrate strong internal consistency reliability and construct validity, supporting its potential use in health care. Further research should validate pMARS across diverse MHAs and contexts and apply IRT to further refine its precision and efficiency.

PMID:42537209 | DOI:10.2196/48828

Phys Rev Lett. 2026 Jul 17;137(3):031501. doi: 10.1103/q81l-xfkx.

ABSTRACT

We show that the canonical formulation of the semiclassical Einstein equation, where the matter terms in the constraints are replaced by expectation values of the corresponding operators in quantum states, is inconsistent due to the nonclosure of the resulting constraint algebra.

PMID:42537109 | DOI:10.1103/q81l-xfkx

Phys Rev Lett. 2026 Jul 17;137(3):030802. doi: 10.1103/m1tx-9mx1.

ABSTRACT

Device-independent (DI) certification allows the verification of quantum systems based solely on observed statistics, without assumptions about their internal structure. While self-testing, the strongest DI certification, of a wide range of quantum states and measurements is done, the self-testing of quantum operations remains underdeveloped. Here, we show in a proof-of-principle way that any quantum unitary can be self-tested within the DI paradigm. For our purpose, we utilize the framework of quantum networks with multiple independent sources. Our Letter provides a fundamental step toward certifying quantum interactions directly from data, without detailed modelling assumptions. Moreover, the result also serves as a crucial ingredient for quantum computation, where verifying that quantum gates perform as intended is essential for building secure and reliable quantum processors.

PMID:42537105 | DOI:10.1103/m1tx-9mx1

Phys Rev Lett. 2026 Jul 17;137(3):033201. doi: 10.1103/g865-9mk1.

ABSTRACT

We report high-precision frequency ratio measurements between optical atomic clocks based on ^{27}Al^{+}, ^{171}Yb, and ^{87}Sr. With total fractional uncertainties at or below 3.2×10^{-18}, these measurements meet an important milestone criterion for redefinition of the second in the International System of Units. Discrepancies in ^{87}Sr ratios at approximately 1×10^{-16} and the Al^{+}/Yb ratio at 1.6×10^{-17} in fractional units compared to our previous measurements underscore the importance of repeated, high-precision comparisons by different laboratories. A key upgrade from our previous work is the use of a common ultrastable reference delivered to all clocks via a 3.6-km phase-stabilized fiber link between two institutions, enabling better accuracy and stability in frequency transfer. Derived from a cryogenic single-crystal silicon cavity, this reference improves comparison stability by a factor of 2-3 over previous systems, with an optical lattice clock ratio achieving a fractional instability of 1.3×10^{-16} at 1 s. Identifying individual clock stabilities with a three-corner-hat measurement, we demonstrate the most stable optical lattice and trapped-ion clocks used in a multispecies comparison. By enabling faster comparisons, this stability will improve sensitivity to nonwhite noise processes and other underlying limits of state-of-the-art optical frequency standards.

PMID:42537076 | DOI:10.1103/g865-9mk1

Phys Rev Lett. 2026 Jul 17;137(3):037102. doi: 10.1103/jkn8-h939.

ABSTRACT

We experimentally study a system of N=4 two-dimensional Brownian particles, each confined in a harmonic trap with identical stiffness. The stiffness switches simultaneously between two values at random Poissonian times. This collective switching drives the system into a nonequilibrium stationary state with strong long-range correlations between the positions of the particles. Remarkably, we find that, despite the presence of hydrodynamic interactions between the particles mediated by the surrounding fluid, the statistics of some observables are insensitive to hydrodynamic interactions and are well described by the noninteracting theory. Comparing with exact theoretical predictions for noninteracting particles, we observe excellent agreement between theory and experiments for three such observables, namely, the correlations between particles, extreme value, and order statistics (maxima, minima, and ranked positions) and the full counting statistics (i.e., the distribution of the number of particles in a finite interval [-L,L] around the trap center).

PMID:42537064 | DOI:10.1103/jkn8-h939

Phys Rev Lett. 2026 Jul 17;137(3):031803. doi: 10.1103/6f6r-51br.

ABSTRACT

The time-dependent CP asymmetry in B^{0}→J/ψρ(770)^{0} 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 during the years 2015-2018. The CP-violation parameters for this process are determined to be 2β_{cc[over ¯]d}^{eff}=0.710±0.084±0.051 rad and |λ|=1.019±0.034±0.024, where the first uncertainty is statistical and the second systematic. This constitutes the first observation of time-dependent CP violation in B^{0}→J/ψρ(770)^{0} decays. Assuming approximate SU(3) flavor symmetry, these results are combined with the previous consistent LHCb measurement to set the most stringent constraint on the penguin contribution, Δϕ_{s}, to the CP-violating phase ϕ_{s} in B_{s}^{0}→J/ψϕ(1020) decays, yielding Δϕ_{s}=5.0±4.6 mrad.

PMID:42537061 | DOI:10.1103/6f6r-51br

Niger J Physiol Sci. 2026 Jun 30;41(1):17-27.

ABSTRACT

Hypertension is a prevalent disease globally and its prevalence is rising in sub-Saharan Africa. Urban-rural differences in the prevalence of hypertension are under-reported in Nigeria. Though hypertension is known to be related to obesity, the nature of the relationship is still unclear. This study sought to interrogate these and thus enrolled a total of 1,755 subjects (59% females) from five states in the old Eastern Region of Nigeria. Standard protocols and definitions were used to take measurements and diagnose relevant disease states. Appropriate statistical tools were used for data analysis. The results indicate that prehypertension was found in 40.0% of males and 27.5% of females while hypertension was found in 19.1% of males and 18.6% of females. The prevalence of (pre)hypertension among urban and rural males were similar (19%). However, prehypertension was more prevalent among urban females (29.1% Vs 24.3%); while hypertension was more prevalent among rural females (21.9% Vs 17.1%). SBP was found to be positively and significantly correlated with weight, waist circumference, hip circumference, waist-to-height ratio and body mass index in the general population. When disaggregated based on blood pressure phenotypes, the correlations were found to be consistent mostly among normotensive subjects and among females. Among subjects with (pre)hypertension, the correlations varied in strength and direction depending on sex and measure of adiposity used. The urban-rural difference in the prevalence of hypertension and the relationship between hypertension and obesity are not linear.

PMID:42537033

JMIR Cardio. 2026 Jul 31;10:e92930. doi: 10.2196/92930.

ABSTRACT

Synthetic data offer significant potential for cardiology research by enabling data sharing, preserving privacy, and supporting machine learning model development. By generating artificial patient records that reflect real-world distributions, synthetic data can accelerate clinical research, improve model performance for rare cardiovascular conditions, and facilitate transnational collaborations that would otherwise be restricted by data-sharing barriers. Despite these advantages, the increasing use of synthetic data raises important ethical, regulatory, and methodological concerns that remain insufficiently addressed. Key challenges include assessing the validity and generalizability of synthetic datasets, understanding their limitations in representing complex and heterogeneous patient populations, and preventing the amplification of existing biases in cardiovascular care. Current regulatory frameworks, including the General Data Protection Regulation (GDPR) and Health Insurance Portability and Accountability Act (HIPAA), do not fully address emerging risks such as reidentification and data leakage, and there is no harmonized guidance to govern the use of synthetic data as stand-alone evidence for medical device evaluation or therapeutic research. In this viewpoint, we argue that responsible integration of synthetic data in cardiology requires, first, clear differentiation between synthetic data as a privacy-preserving distributional substitute and synthetic data as a counterfactual simulation tool, and, second, fit-for-purpose governance frameworks that pair rigorous utility and fidelity testing with explicit, adversary-aware privacy evaluation before synthetic cohorts are accepted as evidence in research or product evaluation. A prerequisite for that governance is conceptual clarity about what synthetic data are being used for. Synthetic data in health care serve 2 fundamentally distinct roles that carry entirely different validity requirements, failure modes, and regulatory implications, yet they are routinely conflated. The first role is as a privacy-preserving distributional substitute: the goal is statistical fidelity to the real data distribution, so that analyses of the synthetic dataset yield results equivalent to those of the original. The second role is as a tool for counterfactual simulation: the goal is to generate data that could not have been observed, such as rare conditions, hypothetical interventions, or extrapolations to new populations. These 2 roles are methodologically distinct. A dataset that accurately reflects real-world distributions may be inadequate for extrapolating findings to underrepresented subgroups. Conversely, a simulator optimized for novel scenario generation may systematically diverge from real-world distributions. This distinction informs every subsequent discussion of validity, bias, and regulation in this viewpoint and our proposed 4 concrete actions for the cardiology research community, including mandatory 3-layer (fidelity, utility, and privacy) validation, systematic subgroup reporting, explicit intended-use scoping, and domain-specific acceptability thresholds for synthetic data-based evidence.

PMID:42537019 | DOI:10.2196/92930