The constraint equations in Maxwell theory are investigated. In analogy with some recent results on the constraints of general relativity it is shown, regardless of the signature and dimension of the ambient space, that the "divergence of a vector field" type constraints can always be put into linear first order hyperbolic form for which global existence and uniqueness of solutions to an initial-boundary value problem is guaranteed.

Benefits of baby swimming have been established, but there is limited knowledge about the methodologies used by practitioners. To address this knowledge gap, this study aimed to categorize and classify the equipment and environmental used in baby swimming programs worldwide. A descriptive categorical content analysis approach was employed to analyse videos of baby swimming programs obtained from YouTube. The framework created was validated for interrater reliability, and a pilot study was conducted to classify videos from different countries based on the equipment and environment used. Results indicated that the physical environments observed were pool tanks and swimming pools with and without depth reduction zones, while the equipment used included assistive devices, toys, and clothes. This study represents a significant first step in the development of a comprehensive tool to systematize and characterize the methodologies used in baby swimming programs globally.

Earth's global surface temperature shows variability on an extended range of temporal scales and satisfies an emergent scaling symmetry. Recent studies indicate that scale invariance is not only a feature of the observed temperature fluctuations, but an inherent property of the temperature response to radiative forcing, and a principle that links the fast and slow climate responses. It provides a bridge between the decadal- and centennial-scale fluctuations in the instrumental temperature record, and the millennial-scale equilibration following perturbations in the radiative balance. In particular, the emergent scale invariance makes it possible to infer equilibrium climate sensitivity (ECS) from the observed relation between radiative forcing and global temperature in the instrumental era. This is verified in ensembles of Earth system models (ESMs), where the inferred values of ECS correlate strongly to estimates from idealized model runs. For the range of forcing data explored in this paper, the method gives best estimates of ECS between 2.3 and 3.4 K.

Roma is the largest ethnic minority of Europe with poor health status, which is poorly explored due to legal constrains of ethnicity assessment. We aimed to elaborate health-indicators for adults living in segregated Roma settlements (SRS) representing the most vulnerable Roma subpopulation. SRSs were mapped in a study area populated by 54682 adults. Records of all adults living in the study area were processed in the National Institute of Health Insurance Fund Management. Aggregated, age-sex standardized SRS-specific and non-SRS-specific indicators on healthcare utilization and premature death along with the ratio of them (RR) were computed with 95% confidence intervals. The rate of GP appointments was significantly higher among SRS inhabitants (RR=1.152, 95%CI: 1.136–1.167). The proportion of subjects hospitalized (RR=1.286, 1.177–1.405), and the reimbursement for inpatient care (RR=1.060, 1.057–1.064) were elevated for SRS. Premature mortality was significantly higher in SRSs (RR=1.711, 1.085-2.696). Our study demonstrated that it is possible to compute the SRS-specific version of the routine healthcare indicators without violating the protection of personal data by converting a sensitive ethical issue to a non-sensitive small area geographical analysis; there is an SRS-specific healthcare utilization pattern, which is associated with elevated costs and increased risk of premature death.