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Canadian healthcare systems are facing unprecedented challenges in recruiting and retaining workers. Literature on healthcare burnout and professional exit suggest multiple intersecting causes. Understaffing, residual trauma, compassion fatigue, demanding hours, rigid hierarchies, and moral distress, interlock and compound to create and sustain the current burnout crisis. In the face of this frightening reality, healthcare institutions and governments are investing billions in wellness programs, aimed at attracting new workers and incentivizing staff retention. Amid this rapidly evolving landscape, our workshop asked: Does clinical ethics have a role in addressing the ongoing burnout crisis? If, as the research suggests, moral distress and moral injury are key drivers of the burnout problem, should bioethics be part of the “wellness” solution?. [ABSTRACT FROM AUTHOR]

Prior to the COVID-19 pandemic (hereafter, ‘the pandemic’), there was already widespread concern about the adequacy of health care resources across Canada. The COVID-19 pandemic exacerbated these concerns exponentially, widening already significant cracks in provincial health care systems. Currently the system is struggling with the exacerbation of wait times for surgeries previously delayed by mandated closures during the pandemic. In Ontario, the backlog of surgeries, and associated backlogs in radiology and other services critical to paediatric care, led to the creation of a consortium of paediatric hospitals committed to advocacy for more funding for paediatrics. Thus far, the provincial and federal governments have agreed to a one-time cash infusion, but the consortium is calling for a permanent increase in funding for paediatrics. A challenge is that the adult sector has also suffered from delays and backlogs. Furthermore, as already noted, older adults have borne the brunt of morbidity and mortality associated with COVID-19. The challenge for the paediatric sector is whether and how to defend the prioritization of children and youth. In this paper, we review four approaches to just allocation – utilitarian ageism, fair innings, the prudential lifespan approach, and prioritarian ageism – and examine their strengths and weaknesses. We conclude by endorsing prioritarian ageism (prioritarianism). Prioritarianism retains the strengths of utilitarian ageism and fair innings while avoiding their weaknesses. Furthermore, because prioritarianism does not treat age as an independent moral criterion, allocation schemes based on this foundation are less susceptible to legal challenge and may be more palatable to the general public. [ABSTRACT FROM AUTHOR]

Migration is widely considered a sensitive and contested area of EU policymaking, with Member States reluctant to cede control. Yet, supranational rules on 'legal migration' increasingly reduce Member State discretion to control migration. While Commission entrepreneurship has been proposed as an explanation, its importance for supranational outcomes remains unclear. To understand the role of Commission entrepreneurship in enabling supranational policy outcomes, this study traces the negotiations of on one central labour migration policy, the Intra-Corporate Transferee Directive. I demonstrate how the Commission was able to defuse opposition by proposing a narrow policy instrument and framing it as a matter of business needs, international obligations and competitiveness rather than labour migration. This enabled an environment of 'quiet politics' where concerns over sovereignty and control were tuned down to a preference for administrative flexibility. The findings have implications for our understanding of the dynamics of supranationalization in politically sensitive policy areas. [ABSTRACT FROM AUTHOR]

Why do some migration policies cause controversial debates while others are barely noticed? And why do migration policies consistently fail to meet their stated objectives? This paper argues that identifying the underlying perspective that informs migration policy-making can be a productive tool to answer these questions. I start by reviewing notions of 'migration' and 'mobility' used in political and scholarly discourse and argue that the ways of differentiating between the two entail not only biases related to norms of sedentariness or social hierarchies, but also blind spots for how states and individuals perceive cross-border movements. As an alternative, I propose to conceptualise 'migration' and 'mobility' as categories reflecting perspectives that either normalise sedentariness and fixed borders or movement and fluidity. In a second step, I combine the two perspectives with the perceptions of the state as the main regulator of movement and the individual on the move, leading to four ideal-typical situations of aligned and non-aligned perspectives on human movement. This notion of intersecting perspectives can help us explain both policy-making processes and the impact of migration policies. This is illustrated through two examples of EU-level policies on intra-corporate transferees on the one hand and family reunification on the other. [ABSTRACT FROM AUTHOR]

We develop a weakly intrusive framework to simulate the propagation of uncertainty in solutions of generic hyperbolic partial differential equation systems on graph-connected domains with nodal coupling and boundary conditions. The method is based on the Stochastic Finite Volume (SFV) approach, and can be applied for uncertainty quantification (UQ) of the dynamical state of fluid flow over actuated transport networks. The numerical scheme has specific advantages for modeling intertemporal uncertainty in time-varying boundary parameters, which cannot be characterized by strict upper and lower (interval) bounds. We describe the scheme for a single pipe, and then formulate the controlled junction Riemann problem (JRP) that enables the extension to general network structures. We demonstrate the method's capabilities and performance characteristics using a standard benchmark test network. • Formulation of a stochastic hyperbolic PDE as a high-dimensional parametric PDE. • Novel SFV method for quantification of intertemporal uncertainty in systems of conservation laws posed on graphs. • Formulation of the stochastic junction Riemann problem to compute numerical fluxes at the nodes of the graph. • Application of the SFV method to a real-world problem of stochastic gas flows on networks. • Convergence analysis for the statistical moments of the solution. [ABSTRACT FROM AUTHOR]

We study a three-level explicit in time higher-order vector compact scheme, with additional n sought functions approximating second order non-mixed spatial derivatives of the solution, for an initial-boundary value problem for the n -dimensional wave equation and acoustic wave equation, with the variable speed of sound, n ⩾ 1. We also approximate the solution at the first time level in a similar two-level manner, without using derivatives of the initial data as usual. For the first time, under the CFL-type conditions, new stability bounds in the standard and stronger mesh energy norms and the discrete energy conservation laws are presented, and the corresponding error bounds of the orders 4 and 3.5 are rigorously proved. Generalizations to the cases of the nonuniform meshes in space and time are described. Results of various numerical experiments are also included. [ABSTRACT FROM AUTHOR]

We consider the so-called four-equation model for dynamics of the heterogeneous compressible binary mixtures with the Noble-Abel stiffened-gas equations of state. We exploit its quasi-homogeneous form that arises after excluding the volume concentrations from the sought functions and is based on a quadratic equation for the common pressure of the components. We present new properties of this equation and a simple formula for the squared speed of sound, suggest an alternative derivation for a formula relating it to the squared Wood speed of sound and state the pressure balance equation. For the first time, we give a quasi-gasdynamic-type regularization of the heterogeneous model (in the quasi-homogeneous form), construct explicit two-level in time and symmetric three point in space finite-difference scheme without limiters to implement it in the 1D case and present numerical results. [ABSTRACT FROM AUTHOR]

A reduced order model technique is presented to perform the parametric Noise, Vibration and Harshness (NVH) study of a vehicle body-in-white (BIW) structure characterized by material and shape design variables. The ultimate goal is to develop a methodology which allows to efficiently explore the variation in the design space of the BIW static and dynamic global stiffnesses, such that the NVH performance can be evaluated already in the preliminary phase of the development process. The proposed technique is based on the proper generalized decomposition (PGD) method. The obtained PGD solution presents an explicit dependency on the introduced design variables, which allows to obtain solutions in 0.1 milliseconds and therefore opens the door to fast optimization studies and real-time visualizations of the results in a pre-defined range of parameters. The method is nonintrusive, such that an interaction with commercial software is possible. A parametrized finite element (FE) model of the BIW is built by means of the ANSA CAE preprocessor software, which allows to account for material and geometric parameters. A comparison between the parametric NVH solutions and the full-order FE simulations is performed using the MSC-Nastran software, to validate the accuracy of the proposed method. In addition, an optimization study is presented to find the optimal materials and shape properties with respect to the NVH performance. Finally, in order to support the designers in the decision-making process, a graphical interface app is developed which allows to visualize in real-time how changes in the design variables affect pre-defined quantities of interest. [ABSTRACT FROM AUTHOR]

Simple Summary: Immunotherapy is an innovative treatment that is highly effective against certain cancers, such as skin and lung cancer. However, for colorectal cancer, one of the most prevalent cancers, it does not benefit most patients. Recent research suggests that by treating liver metastases first, immunotherapy might become effective for those with colorectal cancer. This review delves into the current evidence supporting this strategy, aiming to understand its underlying mechanisms and determine the best way to implement it. If this approach gains widespread acceptance, it could revolutionize how we treat colorectal cancer patients. Immunotherapy has revolutionized the treatment of several cancers, including melanoma and lung cancer. However, for colorectal cancer, it is ineffective for 95% of patients with microsatellite-stable disease. Recent evidence suggests that the liver's immune microenvironment plays a pivotal role in limiting the effectiveness of immunotherapy. There is also evidence to show that targeting liver metastases with locoregional therapies, such as surgery or irradiation, could potentiate immunotherapy for these patients. This review presents evidence from preclinical studies regarding the underlying mechanisms and from clinical studies that support this approach. Furthermore, we outline potential directions for future clinical trials. This innovative strategy could potentially establish immunotherapy as an effective treatment for MS-stable colorectal cancer patients, which are currently considered resistant. [ABSTRACT FROM AUTHOR]

We deal with the reduced four-equation model for the dynamics of heterogeneous compressible binary mixtures with the stiffened gas equations of state. We study its further reduced form, with the excluded volume concentrations, and with a quadratic equation for the common pressure of the components; this form can be called a quasi-homogeneous form. We prove new properties of the equation, derive simple formulas for the squared speed of sound, and present an alternative proof for a formula that relates it to the squared Wood speed of sound; also, a short derivation of the pressure balance equation is given. For the first time, we introduce regularizations of the heterogeneous model (in the quasi-homogeneous form). Previously, regularizations of such types were developed only for the homogeneous mixtures of perfect polytropic gases, and it was unclear how to cover the case considered here. In the 1D case, based on these regularizations, we construct new explicit two-level in time and symmetric three-point in space finite-difference schemes without limiters and provide numerical results for various flows with shock waves. [ABSTRACT FROM AUTHOR]

Recent years saw significant developments concerning the role of children in the political context. Yet, children today remain excluded from meaningful political influence, and children's enfranchisement stands as a main point of contention. The article posits the UN Convention on the Rights of the Child (CRC) as a decisive legal and theoretical basis for conceptualising children's political rights, political participation and voting. It explores key CRC provisions that relate to children in the political context and analyses the UN Committee on the Rights of the Child's (CRC Committee) work to map what exists and what remains missing and under-developed in this discussion. Specifically, the article elaborates on the right to be heard, revealing the CRC Committee's evolutive interpretive approach concerning its implementation in the political context. The article also focuses on children's enfranchisement, exploring the CRC's potential to advocate for lowering the voting age from a child rights-based perspective. [ABSTRACT FROM AUTHOR]

We deal with multidimensional regularized systems of equations for the one-velocity and one-temperature inert gas mixture dynamics consisting of the balance equations for the mass of components and the momentum and total energy of the mixture, with diffusion fluxes between the components as well as the viscosity and heat conductivity terms. The regularizations are kinetically motivated and aimed at constructing conditionally stable symmetric in space discretizations without limiters. We consider a new combined form of regularizing velocities containing the total pressure of the mixture. To confirm the physical correctness of the regularized systems, we derive the balance equation for the mixture entropy with the non-negative entropy production, under generalized assumptions on the diffusion fluxes. To confirm nice regularizing properties, we derive the systems of equations linearized at constant solutions and provide the existence, uniqueness and L2-dissipativity of weak solutions to an initial-boundary problem for them. For the original systems, we also discuss the related Petrovskii parabolicity property and its important corollaries. In addition, in the one-dimensional case, we also present the special three-point and symmetric finite-difference discretization in space of the regularized systems and prove that it inherits the entropy correctness property. We also give results of numerical experiments confirming that the discretization is able to simulate well various dynamic problems of contact between two different gases. [ABSTRACT FROM AUTHOR]

Composite materials are gaining popularity as an alternative to classical materials in many different applications. Moreover, their design is even more flexible due to the potential of additive manufacturing. Thus, one can produce a tailored composite laminate with the optimal values of some design parameters providing the desired mechanical performance. In this context, having a parametric numerical model for the mechanical response of the composite laminate is essential to compute the optimal parameters. In the present paper, the design parameters under consideration are the angles describing the orientation of the reinforcement fibers in different layers or patches of the composite laminates. We obtain a generalized solution using Proper Generalized Decomposition (PGD) which is adopted to provide solutions with explicit parametric dependence. The Tsai-Wu failure criterion is used to estimate first ply failure. In this context, Tsai-Wu criterion is used as the objective function for the optimization of the fibre orientations in the laminate. The PGD solution provides also sensitivities for a gradient-based optimization algorithm. The potentiality and efficiency of the presented approach is demonstrated through some numerical tests. [ABSTRACT FROM AUTHOR]

A regularization of two types and aggregation are performed for the system of equations of motion for a multivelocity mixture of viscous incompressible fluids, and new multivelocity and single-velocity systems are constructed. For all of them, elliptic equations for the pressure and dissipative balance equations for the total energy of the mixture (the sum of its kinetic and potential energies) are derived. [ABSTRACT FROM AUTHOR]

We study the Cauchy problems for a first-order symmetric hyperbolic system of equations with variable coefficients and its singular perturbations that are second-order strongly parabolic and hyperbolic systems of equations with a small parameter in front of the second derivatives with respect to and t. The properties of solutions of all three systems are formulated, and estimates of order are given for the difference between the solutions of the original system and systems with perturbations for an initial function w0 of smoothness α in the sense of , . For , a broad class of discontinuous functions w0 is covered. Applications to the linearized system of gas dynamics equations and to the linearized parabolic and hyperbolic second-order quasi-gasdynamic systems of equations are given. [ABSTRACT FROM AUTHOR]

We study an explicit two-level finite difference scheme on staggered meshes, with a quasi-hydrodynamic regularization, for 1D barotropic gas dynamics equations. We derive both necessary conditions and sufficient conditions close to them, for L2-dissipativity of solutions to the Cauchy problem linearized on a constant solution, for any background Mach number . We apply the spectral approach and analyze matrix inequalities containing symbols of symmetric matrices of convective and regularizing terms. We consider the cases where either the artificial viscosity or the physical viscosity is used. A comparison with the spectral von Neumann condition is also given for . [ABSTRACT FROM AUTHOR]

Two aggregated regularized systems of equations for a multicomponent homogeneous gas mixture are considered. An entropy balance equation with a non‐negative entropy production is derived for them in the presence of diffusion fluxes. The existence, uniqueness and L2‐dissipativity of weak solutions to an initial‐boundary value problem for the systems linearized on a constant solution are established. The Petrovskii parabolicity and the local in time classical unique solvability of the Cauchy problem are also proved for the aggregated systems themselves. [ABSTRACT FROM AUTHOR]

One-dimensional regularized systems of equations for the general (multi-velocity and multi-temperature) and one-velocity and one-temperature compressible multicomponent gas mixture dynamics are considered in the absence of chemical reactions. Two types of the regularization are taken. For the latter system, diffusion fluxes between the components of the mixture are taken into account. For both the systems, the important mixture entropy balance equations with non-negative entropy productions are valid. By generalizing a discretization constructed previously in the case of a single-component gas, we suggest new nonstandard symmetric three-point spatial discretizations for both the systems which are not only conservative in mass, momentum, and total energy but also satisfy semi-discrete counterparts of the mentioned entropy balance equations with non-negative entropy productions. Importantly, the basic discretization in the one-velocity and one-temperature case is not constructed directly but by aggregation of the discretization in the case of general mixture, and that is a new approach. In this case, the results of numerical experiments are also presented for contact problems between two different gases for initial pressure jumps up to 2500. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is associated with significant cognitive and psychiatric conditions. Neuropsychiatric symptoms can persist for years following brain injury, causing major disruptions in patients' lives. In this review, we examine the role of glutamate as an aftereffect of TBI that contributes to the development of neuropsychiatric conditions. We hypothesize that TBI causes long-term blood–brain barrier (BBB) dysfunction lasting many years and even decades. We propose that dysfunction in the BBB is the central factor that modulates increased glutamate after TBI and ultimately leads to neurodegenerative processes and subsequent manifestation of neuropsychiatric conditions. Here, we have identified factors that determine the upper and lower levels of glutamate concentration in the brain after TBI. Furthermore, we consider treatments of disruptions to BBB integrity, including repairing the BBB and controlling excess glutamate, as potential therapeutic modalities for the treatment of acute and chronic neuropsychiatric conditions and symptoms. By specifically focusing on the BBB, we hypothesize that restoring BBB integrity will alleviate neurotoxicity and related neurological sequelae. [ABSTRACT FROM AUTHOR]

During groundwater pumping from unconfined aquifers, evapotranspiration can be reduced as the water table drops, a process known as salvage. This phenomenon must be included in water balance assessments for accurate predictions of groundwater withdrawals. Although the salvage phenomenon has been well understood for a long time, i.e., since Theis' pioneering studies, the models that were later developed by Bredehoeft always relied on numerical techniques to treat the inherent non-linearity, most commonly using MODFLOW. Analytical methods have been previously used with success for practical evaluation of water balance components such as stream depletion rates. This work presents a novel analytical solution of the Bredehoeft problem. It is a breakthrough in analytical evaluation of transient salvage losses induced by groundwater withdrawals due to declines of water table. We evaluate stream depletion and loss of storage in addition to salvage, using the new model. Detailed analysis of the solution using COMSOL software indicates that the linear approximation used in the analytical solution is accurate for most practical cases. Diagrams for drawdown, water balance and evaluation of solution accuracy are presented, considering a broad range of problem parameters. Results can be used for analyses of watershed-scale water balances. • A novel analytical solution of salvage rate for pumping near a stream is derived. • Solution implements an approximation of linearized evapotranspiration term. • Solution is compared to numerical results using COMSOL. • Solution is found to be accurate for a wide range of physical parameters. • Results can be used for analyses of watershed-scale water balances. [ABSTRACT FROM AUTHOR]

We study an explicit two-level finite-difference scheme for a linearized multidimensional quasi-gasdynamic system of equations. For an initial-boundary value problem on a nonuniform rectangular mesh, sufficient conditions of Courant-type for L2-dissipativity are derived for the first time by applying the energy method. For the Cauchy problem on a uniform mesh, both necessary and sufficient conditions for L2-dissipativity in the spectral method are improved. A new form of specifying the relaxation parameter is indicated which guarantees that the Courant-type number is uniformly bounded from above and below with respect to both the mesh and the Mach number. [ABSTRACT FROM AUTHOR]

Scaffolds are microporous biocompatible structures that serve as material support for cells to proliferate, differentiate and form functional tissue. In particular, in the field of bone regeneration, insertion of scaffolds in a proper physiological environment is known to favour bone formation by releasing calcium ions, among others, triggering differentiation of mesenchymal cells into osteoblasts. Computational simulation of molecular distributions through scaffolds is a potential tool to study the scaffolds' performance or optimal designs, to analyse their impact on cell differentiation, and also to move towards reduction in animal experimentation. Unfortunately, the required numerical models are often highly complex and computationally too costly to develop parametric studies. In this context, we propose a computational parametric reduced-order model to obtain the distribution of calcium ions in the interstitial fluid flowing through scaffolds, depending on several physical parameters. We use the well-known Proper Orthogonal Decomposition (POD) with two different variations: local POD and POD with quadratic approximations. Computations are performed using two realistic geometries based on a foamed and a 3D-printed scaffolds. The location of regions with high concentration of calcium in the numerical simulations is in fair agreement with regions of bone formation shown in experimental observations reported in the literature. Besides, reduced-order solutions accurately approximate the reference finite element solutions, with a significant decrease in the number of degrees of freedom, thus avoiding computationally expensive simulations, especially when performing a parametric analysis. The proposed reduced-order model is a competitive tool to assist the design of scaffolds in osteoinduction research. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke is a critical condition that can result in disability and death. The consequences of this medical condition depend on various factors, including the size of the stroke, affected brain region, treatment onset, and the type of treatment. The primary objective of stroke treatment is to restart ischemic penumbra tissue perfusion and reduce infarct volume by sustaining blood flow. Recent research on the condition's pathological pathways and processes has significantly improved treatment options beyond restoring perfusion. Many studies have concentrated on limiting injury severity via the manipulation of molecular mechanisms of ischemia, particularly in animal research. This article reviews completed and ongoing research on the development of acute ischemic stroke drugs. This study focuses on three main categories of antithrombotic drugs, thrombolytic drugs, and neuroprotective agents. The paper outlines findings from animal and clinical trials and explores the working mechanisms of these drugs. [ABSTRACT FROM AUTHOR]

(1) Background: We aimed to explore the association between neoadjuvant treatment, tumor-infiltrating immune lymphocyte (TIL), and tumor-associated macrophage (TAM) and survival in patients with esophageal adenocarcinoma. (2) Methods: Patients who underwent esophagectomy were divided into three groups according to their treatment modality and tumor regression grade (TRG): (i) surgery-only group (SG), (ii) good responders (GR) group (TRG 0–1), and (iii) bad responders (BR) group (TRG 2–3). We then carried out statistical correlations of the immunofluorescence analysis of the immune infiltrate in the esophageal surgical specimens with several clinical and pathological parameters. In addition, we analyzed The Cancer Genomic Atlas (TCGA) dataset for differences in TILs, TAMs, and protein expression in immune pathways. (3) Results: Forty-three patients (SG—15, GR—13, and BR—13) were evaluated. The highest enrichment of CD3+ (p < 0.001), CD8+ (p = 0.001) and CD4+ (p = 0.009) was observed in the stroma of GR patients. On multivariate analysis, only CD8+ T cell and signet-ring features were independent prognostic factors for overall survival. In TCGA analysis, we identified overexpression of TAM and colony-stimulating factor 1 receptor (CSF-1R). (4) Conclusions: High enrichment of lymphocyte subpopulations in the microenvironment of esophageal adenocarcinoma is associated with a favorable response to neoadjuvant treatment and an improved patient outcome. [ABSTRACT FROM AUTHOR]

We study a quasihydrodynamic system of equations for a homogeneous (with common velocity and temperature) multicomponent gas mixture in the absence of chemical reactions with a common regularizing velocity. For this system, we derive an entropy balance equation with nonnegative entropy production in the presence of diffusion fluxes of the mixture components. In the absence of diffusion fluxes, a system of equations linearized on a constant solution is constructed in a new way. This system is reduced to a symmetric form, the -dissipativity of its solutions is proved, and the degeneracy (with respect to the densities of the mixture components) of the parabolic property of the original system is established. In fact, the system under study has a composite type. The obtained properties mathematically rigorously reflect its physical well-posedness and the dissipative nature of quasihydrodynamic regularization. [ABSTRACT FROM AUTHOR]

Metacognition is defined as the process of regulating behavior and having self-perception of own performance. An application of video modeling (VM) was used as a technological solution for assessing self-perception in daily situations among typical adolescents, compared to parental reports and to an objective performance-based assessment. One hundred and three adolescents (30 boys, 73 girls, mean age =15.1, SD = 1.9), viewed five clusters of videotaped scenarios of teen actors performing daily activities entailing strategy use. Half of the scenarios were classified as "Type A" indicating a more organized approach to accomplishing a task, the other half were "Type B" scenarios indicated a less organized approach to accomplishing the same tasks. Participants were asked to choose the scenarios that best represent their own daily performance using the VM application. The participants then completed the WCPA, an executive function (EF) performance-based assessment. Their parents completed the BRIEF as an indication of EF behaviors in the home environment. 46% of the adolescents associated their performance with a less organized approach yet parental reports indicated adaptive daily performance and their ability to complete the WCPA was as correct as it was for the 56% of participants who associated their performance with a more organized approach. Unexpectedly, the participants who associated their ability as less organized presented successful behaviors in the home environment and successfully performed the WCPA. Therapists should be aware that clients may achieve success in daily tasks even though they may cope with cognitive challenges in unexpected ways. Therapists may expect adolescent clients to approach tasks in a variety of ways, using different strategies for coping with everyday cognitive challenge. Therapists need to acknowledge that there is no ideal strategy that provides a solution for all individuals. Mediating a guided discovery of strategies through use of VM technology may customize intervention for each client's needs, assuring a client-centered approach and may encourage a collaboration of therapists and clients in search for the strategies that work best for them. [ABSTRACT FROM AUTHOR]

Objective: To investigate the distribution of parturients at Hospital Municipal da Vila Santa Catarina Dr. Gilson de Cássia Marques de Carvalho according to the Robson classification, identify the cesarean rate in each Robson Group, and understand which group contributes more to the prevalence of Cesarean sections. Methods: This is a retrospective observational cross-sectional study conducted through the analysis of medical records of parturients admitted to Hospital Municipal da Vila Santa Catarina Dr. Gilson de Cássia Marques de Carvalho from October 2016 to August 2019. Results: A total of 9,794 births were recorded, and 31% were by Cesarean section. The most prevalent Robson Groups were Group 3 (25.7%-2,519), 1 (22.8%-2,234), and 5 (20.5%-2,006). The relative contribution of Cesarean sections was greatest in Groups 5 (39%), 2 (18%), and 1 (12.5%). Conclusion: This study demonstrated the Robson classification is useful to lead to a more critical view, identifying the groups that deserve more attention, since they are the major contributors to cesarean rates; hence, the management protocols could be modified aim to reduce cesarean rates. [ABSTRACT FROM AUTHOR]

Curie point depth can be used as a proxy for plate temperatures. Data from the North Atlantic (10°–50°N) are used here to determine if the observed oscillations and patterns in Curie depths could be a subproduct of small-scale thermal instabilities arising at the bottom of the lithospheric plates. Our numerical models suggest that small-scale convection (SSC) cells could produce thermal perturbations at isotherms as low as the Curie point. These results are compatible with North Atlantic observations in terms of wavelengths (150–300 km), amplitudes (∼4 km) and orientations of the instabilities. Observed Curie-point depth oscillations before the onset (70 to 90 Myr) of SSC could also be linked to other different processes. We suggest that, in the case of the North Atlantic lithosphere, the spreading rate variation and the melt and upwelling could be intricately linked and cause a different pattern of SSC. [ABSTRACT FROM AUTHOR]

Logarithmically optimal in theory and fast in practice, direct algorithms for implementing a tensor product finite element method (FEM) based on tensor products of 1D high-order FEM spaces on multi-dimensional rectangular parallelepipeds are proposed for solving the N-dimensional Poisson-type equation () with Dirichlet boundary conditions. The algorithms are based on well-known Fourier approaches. The key new points are a detailed description of the eigenpairs of the 1D eigenvalue problems for the high-order FEM, as well as fast direct and inverse eigenvector expansion algorithms that simultaneously employ several versions of the fast Fourier transform. Results of numerical experiments in the 2D and 3D cases are presented. The algorithms can be used in numerous applications, in particular, to implement tensor product high-order finite element methods for various time-dependent partial differential equations, including the multidimensional heat, wave, and Schrödinger ones. [ABSTRACT FROM AUTHOR]

For an aggregated quasi-gasdynamic system of equations for a homogeneous gas mixture, we give an entropy balance equation with a nonnegative entropy production in the presence of diffusion fluxes. We also derive the existence, uniqueness, and L2-dissipativity of weak solutions to an initial-boundary value problem for the system linearized at a constant solution. Additionally, the Petrovskii parabolicity and local-in-time classical unique solvability of the Cauchy problem for the quasi-gasdynamic system itself are established. [ABSTRACT FROM AUTHOR]

The pathways and timing of drainage from the inundated centers of ice-wedge polygons in a warming climate have important implications for carbon flushing, advective heat transport, and transitions from methane to carbon dioxide dominated emissions. Here, we expand on previous research using a recently developed analytical model of drainage from a low-centered polygon. Specifically, we perform (1) a calibration to field data identifying necessary model refinements and (2) a rigorous model sensitivity analysis that expands on previously published indications of polygon drainage characteristics. This research provides intuition on inundated polygon drainage by presenting the first in-depth analysis of drainage within a polygon based on hydrogeological first principles. We verify a recently developed analytical solution of polygon drainage through a calibration to a season of field measurements. Due to the parsimony of the model, providing the potential that it could fail, we identify the minimum necessary refinements that allow the model to match water levels measured in a low-centered polygon. We find that (1) the measured precipitation must be increased by a factor of around 2.2, and (2) the vertical soil hydraulic conductivity must decrease with increasing thaw depth. Model refinement (1) accounts for runoff from rims into the ice-wedge polygon pond during precipitation events and possible rain gauge undercatch, while refinement (2) accounts for the decreasing permeability of deeper soil layers. The calibration to field measurements supports the validity of the model, indicating that it is able to represent ice-wedge polygon drainage dynamics. We then use the analytical solution in non-dimensional form to provide a baseline for the effects of polygon aspect ratios (radius to thaw depth) and coefficient of hydraulic conductivity anisotropy (horizontal to vertical hydraulic conductivity) on drainage pathways and temporal depletion of ponded water from inundated ice-wedge polygon centers. By varying the polygon aspect ratio, we evaluate the relative effect of polygon size (width), inter-annual increases in active-layer thickness, and seasonal increases in thaw depth on drainage. The results of our sensitivity analysis rigorously confirm a previous analysis indicating that most drainage through the active layer occurs along an annular region of the polygon center near the rims. This has important implications for transport of nutrients (such as dissolved organic carbon) and advection of heat towards ice-wedge tops. We also provide a comprehensive investigation of the effect of polygon aspect ratio and anisotropy on drainage timing and patterns, expanding on previously published research. Our results indicate that polygons with large aspect ratios and high anisotropy will have the most distributed drainage, while polygons with large aspect ratios and low anisotropy will have their drainage most focused near their periphery and will drain most slowly. Polygons with small aspect ratios and high anisotropy will drain most quickly. These results, based on parametric investigation of idealized scenarios, provide a baseline for further research considering the geometric and hydraulic complexities of ice-wedge polygons. [ABSTRACT FROM AUTHOR]

We consider compact finite-difference schemes of the 4th approximation order for an initial-boundary value problem (IBVP) for the n-dimensional nonhomogeneous wave equation, n > 1. Their construction is accomplished by both the classical Numerov approach and alternative technique based on averaging of the equation, together with further necessary improvements of the arising scheme for n > 2. The alternative technique is applicable to other types of PDEs including parabolic and time-dependent Schrödinger ones. The schemes are implicit and three-point in each spatial direction and time and include a scheme with a splitting operator for n > 2. For n = 1 and the mesh on characteristics, the 4th order scheme becomes explicit and close to an exact four-point scheme. We present a conditional stability theorem covering the cases of stability in strong and weak energy norms with respect to both initial functions and free term in the equation. Its corollary ensures the 4th order error bound in the case of smooth solutions to the IBVP. The main schemes are generalized for non-uniform rectangular meshes. We also give results of numerical experiments showing the sensitive dependence of the error orders in three norms on the weak smoothness order of the initial functions and free term and essential advantages over the 2nd approximation order schemes in the non-smooth case as well. [ABSTRACT FROM AUTHOR]

We study difference schemes associated with a simplified linearized multidimensional hyperbolic quasi-gasdynamic system of differential equations. It is shown that an explicit two-level vector difference scheme with flux relaxation for a second-order hyperbolic equation with variable coefficients that is a perturbation of the transport equation with a parameter multiplying the highest derivatives can be reduced to an explicit three-level difference scheme. In the case of constant coefficients, the spectral condition for the time-uniform stability of this explicit three-level difference scheme is analyzed, and both sufficient and necessary conditions for this condition to hold are derived, in particular, in the form of Courant type conditions on the ratio of temporal and spatial steps. [ABSTRACT FROM AUTHOR]

We deal with the so-called four-equation model for dynamics of the heterogeneous binary mixtures of the Noble-Abel stiffened-gases (NASGes). In relation to the quasi-homogeneous form of the model, we suggest a new insight on a quadratic equation for the pressure, give a simple formula for the squared speed of sound and present a new proof for a formula connecting it to the Wood speed of sound. A short derivation of the balance equation for the pressure is included as well. [ABSTRACT FROM AUTHOR]

A novel catalyst-free and maskless growth approach is presented to form an ordered geometrical array of three-dimensional (3D) AlGaN/AlN microrods. The growth method is composed of a single growth step using metalorganic vapor phase epitaxy, achieving microstructures with homogeneous diameters, shapes and sizes over relatively large scale (on 2-in. wafer). The 3D AlGaN/AlN heterostructures are grown in a form of micro-sized columns elongated in one direction perpendicular to the substrate surface and with a hexagonal cross section. A careful examination of growth steps revealed that this technology allows to suppress coalescence and lateral overgrowth, promoting vertical 3D growth. Interestingly, two distinct morphologies can be obtained: honeycomb-like hexagonal arrangement perfectly packed and with twisted microrods layout, by controlling strain state in AlN buffer layers. Consequently, 3D AlGaN microrods on tensile-strained AlN templates show a 0° twisted morphology, while on compressive-strained templated a 30° twisted arrangement. Moreover, the optical and crystalline quality studies revealed that the top AlGaN layers of the examined 3D semiconductor structures are characterized by a low native point-defect concentration. These 3D AlGaN platforms can be applied for light emitting devices or sensing applications. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the authors discuss the various topics tackled within the issue, like trial home visits of children in out-of-home care, foster care, and the risk factors for maltreatment after permanency through adoption.

Breast cancer subtypes have not shown significant response to current immunomodulatory therapies. Although most subtypes are treatable, triple negative breast cancer (TNBC), an aggressive highly metastatic cancer, comprising 10-20% of breast cancers, remains an unmet medical need. New strategies are needed in order to overcome flaws in the responsiveness to current TNBC therapies. Our aims were: first, to determine the efficacy of a novel immunomodulatory peptide, C24D, on TNBC and second, to elucidate the molecular mechanism by which C24D induces immune-modulating tumor killing. Using mass spectrometry analysis, we identified CD45 as the C24D binding receptor. In vitro and in vivo TNBC models were used to assess the efficacy of C24D in reversing TNBC-induced immunosuppression and in triggering immune-modulated tumor cell killing. The CD45 signal transduction pathway was evaluated by western blot and FACS analyses. We revealed that addition of PBMCs from healthy female donors to TNBC cells results in a cascade of suppressive CD45 intracellular signals. On binding to CD45's extra-cellular domain on TNBC-suppressed leukocytes, the C24D peptide re-activates the Src family of tyrosine kinases, resulting in specific tumor immune response. In vitro, immune reactivation by C24D results in an increase of CD69 + T and CD69+ NK cells, triggering specific killing of TNBC cells. In vivo, C24D induced CD8+ and activated CD56+ tumor infiltrated cells, resulting in tumor apoptosis. Our results should renew interest in molecules targeting CD45, such as the C24D peptide, as a novel strategy for TNBC immunotherapy. [ABSTRACT FROM AUTHOR]

A goal-oriented a-posteriori error estimator is developed for transient coupled thermo-hydro-mechanical (THM) parametric problems solved with a reduced basis approximation. The estimator assesses the error in some specific Quantity of Interest (QoI). The goal-oriented error estimate is derived based on explicitly-computed weak residual of the primal problem and implicitly-computed adjoint solution associated with the QoI. The time-dependence of the coupled THM system poses an additional complexity as the auxiliary adjoint problem evolves backwards in time. The error estimator guides a greedy adaptive procedure that constructs progressively an optimal reduced basis by smartly selecting snapshot points over a given parametric training sample. The reduced basis obtained is used to drastically reduce the coupled system spatial degrees of freedom by several orders of magnitude. The computational gain obtained from the developed methodology is demonstrated through applications in 2D and 3D parametrized problems simulating the evolution of coupled THM processes in rock masses. [ABSTRACT FROM AUTHOR]

We consider a multidimensional hyperbolic quasi-gasdynamic system of differential equations of the second order in time and space linearized on a constant solution (with an arbitrary velocity). For the linearized system with constant coefficients, we study the implicit three-level weighted and two-level vector difference schemes. The important domination property of the operator of viscous terms (with no allowance for the relaxation parameter) over the operator of convective terms is derived. We apply this property to prove by the energy method that, regardless of the Mach number, our implicit schemes on a nonuniform rectangular mesh (without any conditions on the mesh steps) are stable with respect to the initial data and the right-hand side uniformly in time and the relaxation parameter. [ABSTRACT FROM AUTHOR]

We study an explicit two-level symmetric (in space) finite-difference scheme for the multidimensional barotropic gas dynamics system of equations with quasi-gasdynamic regularization linearized at a constant solution (with an arbitrary velocity). A criterion and both necessary and sufficient conditions for the L2-dissipativity of the solutions to the Cauchy problem for the scheme are derived by the spectral method. In them, the Courant number is uniformly bounded with respect to the Mach number. [ABSTRACT FROM AUTHOR]

Markov chain Monte Carlo (MCMC) methods have become standard in Bayesian inference and multi‐observable inversions in almost every discipline of the Earth sciences. In the case of geodynamic and/or coupled geophysical‐geodynamic inverse problems, however, the computational cost associated with the solution of large‐scale 3‐D Stokes forward problems has rendered probabilistic formulations impractical. Here we present a novel and extremely efficient method to produce ultrafast solutions of the 3‐D Stokes problem for MCMC simulations. Our approach combines the individual benefits of Reduced Basis techniques, goal‐oriented error formulations, and MCMC algorithms to produce an accurate and computationally efficient surrogate for the forward problem. Importantly, the surrogate adapts itself during the MCMC simulation according to the history of the chain and the goals of the inversion. This maximizes the efficiency of the forward problem and removes the need for preinversion off‐line computations to build a surrogate. We demonstrate the benefits and limitations of the method with several numerical examples and show that in all cases the computational cost is of the order of <1% compared to a traditional MCMC approach. The method is general enough to be applied to a range of problems, including uncertainty quantification/propagation, adjoint‐based geodynamic inversions, sensitivity analyses in mantle convection problems, and in the creating surrogate models for complex forward problems (e.g., heat transfer, seismic tomography, and magnetotellurics). Key Points: An efficient method for producing ultrafast solutions of the 3‐D Stokes problem for mantle convection is presentedThis method is particularly well suited for joint geodynamic‐geophysical probabilistic inverse problems and studies of dynamic topographyThe method is suitable to tackle a range of probabilistic inverse problems where fast solutions for a complex forward problem are needed [ABSTRACT FROM AUTHOR]

Studies have characterised relationships between cognitive status and a variety of clinical epilepsy factors. The aim of this study was to describe a new approach for assessing executive functions in everyday life and its unique expression in adolescents with Genetic Generalised Epilepsies (GGEs) compared with typical peers. Twenty adolescents with a diagnosis of GGEs and 20 typical healthy peers, matched by age and gender, were studied. Assessment of everyday executive function was carried out using: (1) the Weekly Calendar Planning Activity (WCPA), a direct performance based and outcome measure of strategy use and cognitive performance; and (2) Behavior Rating Inventory of Executive Function (BRIEF) parental report. Adolescents with GGEs demonstrated significantly less accuracy, less efficiency and fewer strategies used, as measured by the WCPA. Parents of adolescents with GGEs rated their child's daily performance as less efficient compared with typical peers. Better ratings of executive function (low BRIEF score) were associated with greater WCPA accuracy in the entered appointments. The WCPA provides a useful evaluation of cognitive performance for adolescents with GGEs and a functionally relevant information on task efficiency, self-monitoring and effective strategy use. Direct observation of performance supplements parental ratings and has strong potential to guide intervention and measure outcomes. [ABSTRACT FROM AUTHOR]

Understanding the failure of brittle heterogeneous materials is essential in many applications. Heterogeneities in material properties are frequently modeled through random fields, which typically induces the need to solve finite element problems for a large number of realizations. In this context, we make use of reduced order modeling to solve these problems at an affordable computational cost. This paper proposes a reduced order modeling framework to predict crack propagation in brittle materials with random heterogeneities. The framework is based on a combination of the Proper Generalized Decomposition (PGD) method with Griffith's global energy criterion. The PGD framework provides an explicit parametric solution for the physical response of the system. We illustrate that a non-intrusive sampling-based technique can be applied as a post-processing operation on the explicit solution provided by PGD. We first validate the framework using a global energy approach on a deterministic two-dimensional linear elastic fracture mechanics benchmark. Subsequently, we apply the reduced order modeling approach to a stochastic fracture propagation problem. [ABSTRACT FROM AUTHOR]

People with Parkinson's disease have been shown to have difficulty switching between movement plans. In the great majority of studies, the need to switch between tasks was made explicitly. Here, we tested whether people with Parkinson's disease, taking their normal medication, have difficulty switching between implicitly specified tasks. We further examined whether this switch is performed predictively or reactively. Twenty five people with Parkinson's disease continuously increased or decreased the frequency of their arm movements, inducing an abrupt–but unaware–switch between rhythmic movements (at high frequencies) and discrete movements (at low frequencies). We tested whether that precipitous change was performed reactively or predictively. We found that 56% of participants predictively switched between the two movement types. The ability of people with Parkinson's disease, taking their regular medication, to predictively control their movements on implicit tasks is thus preserved. [ABSTRACT FROM AUTHOR]

We consider the regularized 3D Navier-Stokes-Cahn-Hilliard equations describing isothermal ows of viscous compressible two-component uids with interphase effects. We construct for them a new energy dissipative finite-difference discretization in space, i.e., with the non-increasing total energy in time. This property is preserved in the absence of a regularization. In addition, the discretization is well-balanced for equilibrium ows and the potential body force. The sought total density, mixture velocity and concentration of one of the components are defined at nodes of one and the same grid. The results of computer simulation of several 2D test problems are presented. They demonstrate advantages of the constructed discretization including the absence of the so-called parasitic currents. [ABSTRACT FROM AUTHOR]

We study a symmetric three-level (in time) method with a weight and a symmetric vector two-level method for solving the initial-boundary value problem for a second-order hyperbolic equation with a small parameter multiplying the highest time derivative, where the hyperbolic equation is a perturbation of the corresponding parabolic equation. It is proved that the solutions are uniformly stable in and time in two norms with respect to the initial data and the right-hand side of the equation. Additionally, the case where also multiplies the elliptic part of the equation is covered. The spacial discretization can be performed using the finite-difference or finite element method. [ABSTRACT FROM AUTHOR]

Regularized equations for binary mixtures of viscous compressible gases (in the absence of chemical reactions) are considered. Two new simpler systems of equations are constructed for the case of a homogeneous mixture, when the velocities and temperatures of the components coincide. In the case of moderately rarefied gases, such a system is obtained by aggregating previously derived general equations for binary mixtures of polyatomic gases. In the case of relatively dense gases, the regularizing terms in these equations are subjected to a further substantial modification. For both cases, balance equations for the total mass, kinetic, and internal energy and new balance equations for total entropy are derived from the constructed equations; additionally, the entropy production is proved to be nonnegative. As an example of successful use of the new equations, the two-dimensional Rayleigh–Taylor instability of relatively dense gas mixtures is numerically simulated in a wide range of Atwood numbers. [ABSTRACT FROM AUTHOR]

• Recharge-based approach to modeling lake-aquifer system in semi-arid climate. • Lakes and wetlands identified using simulated head and land surface topography. • Groundwater recharge projections for 21st century are used as the model driver. • Total lake and wetland area likely to change slightly by the end of the century. • The projections have wide bounds of uncertainty for the Nebraska Sand Hills. In a semi-arid climate, groundwater-fed endorheic lakes often have shallow depths and large areas of associated wetlands. These lake-wetland-aquifer systems are sensitive to land use and climate changes. Difficulties of modeling such systems include (a) tracking several thousand lakes and wetlands (LWs), and (b) evaluating major drivers of trends and fluctuations in LW areal coverage. Integrated hydrologic modeling of such systems is prohibitively expensive. We combine traditional groundwater flow modeling (MODFLOW), driven by modern and projected groundwater recharge (GR) estimates, with digital elevation model (DEM)-based geographic information system (GIS) terrain analyses. This approach can be a useful diagnostic tool for estimates of decade-averaged LW areas and numbers, and stream baseflow, facilitating conceptualization and design of more detailed modeling studies. We apply the approach to simulate dynamics of thousands of groundwater-fed LWs in the Nebraska Sand Hills, USA, under GCM-projected GR changes. Compared to the baseline period of 2000–2009, the model indicates an increase by 35% (from 2083 to 2804 km2) of decade-averaged LW area by the end of the 21st century under the Median GR projection, with GR averaging 55.3 mm/yr from 2010 through 2099 (5% increase). Under the same GR projection, the overall numbers of LW is simulated to increase by 18% (from 7331 to 8666). The uncertainty range in the hydrologic response of the system caused by differences among GR projections (Wet and Dry) are also evaluated. [ABSTRACT FROM AUTHOR]