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Lumbar puncture opening pressure (LPOP) exceeding 250mmH2O is key in diagnosing idiopathic intracranial hypertension (IIH), per revised Friedman's criteria. Some patients do not meet LPOP criteria (with or without papilledema), despite having IIH-related symptoms and neuroimaging findings. This study aimed to investigate the radiological findings and clinical symptoms in patients suspected of having IIH without meeting the LPOP criteria. We retrospectively evaluated cerebral venous sinus stenosis using the conduit Farb score (CFS) and other radiological findings suggestive of IIH by computed tomography venography and magnetic resonance venography in females ≥ 18 years-old with chronic headaches, suspected IIH, and LPOP < 250 mm. Eighty-eight women (56 with LPOP < 200 mm H2O and 32 with LPOP ranging between 200 and 250mmH2O) were included. Among patients with LPOP 200–250mmH2O, 40% (12) exhibited three or more radiological findings supporting IIH, compared to 17% (8) in the LPOP < 200 mmH2O group (p = 0.048). Cerebral venous stenosis (CFS ≤ 5) was observed in 80% (24) of those with LPOP 200–250 mmH2O, contrasting with 40% (19) of those with LPOP < 200 mmH2O (p < 0.001). Cerebral venous stenosis was significantly more common in patients with LPOP 200–250 mmH2O than < 200 mmH2O, suggesting that they may benefit from IIH treatment. [ABSTRACT FROM AUTHOR]

States struggle to establish multilateral cooperation on migration – yet they include more and more migration provisions in preferential trade agreements (PTAs). This article sheds light on this phenomenon by introducing the Migration Provisions in Preferential Trade Agreements (MITA) dataset. Covering 797 agreements signed between 1960 and 2020, this dataset offers a fine-grained coding of three types of migration provisions: those that facilitate the international mobility of service providers and labor migrants, protect migrant rights, and control unauthorized migration. Against the backdrop of limping multilateralism, we examine PTAs' migration policy content with regard to two key cooperation dilemmas: conflicts of interest within developed countries and between them and developing countries. Facilitating business and labor mobility might be a possible way around the first dilemma, commonly referred to as the 'liberal paradox': the tension between economic demands for openness and political calls for closure. Nevertheless, this facilitation is largely limited to highly skilled migrants and agreements between developed economies. Provisions for migration control tend to be included in agreements between developed and developing countries, which signals that states use issue-linkages to address the second dilemma, i.e. interest asymmetries. Finally, provisions for migrant rights stand out because they do not deepen over time. Our findings suggest that while PTAs have become an increasingly common venue for migration governance, the issue-linkage between trade and migration cooperation perpetuates entrenched divisions in the international system. The MITA dataset will allow researchers and policymakers to track the evolution of the trade-migration nexus and systematically investigate the motives for and effects of various migration provisions in PTAs. [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]

Parental antenatal attachment refers to the bond developed from parents to their unborn child. This attachment is established based on parents' emotions, perceptions, and behaviors towards their unborn baby. The present research is exploratory and aims to assess the underlying mechanisms linking positive and negative affect to antenatal attachment in first-time mothers, and whether resilience and self-esteem can mediate these relations. Participants were contacted before their prenatal consultation and invited to answer the survey remotely. We performed one study, considering a sample of 265 women (Mage = 29.49; SDage = 5.95) in different stages of their first pregnancy. Our results showed that all variables were significantly related. We then created a mediational model, considering 5000 bootstrap simulations. Results indicated that antenatal attachment is predicted by positive and negative affect, with resilience and self-esteem mediating these relations. Such findings might help better understand the underlying mechanisms that enhance the bonding between mother and child. Environments that promote positive affect, resilience and self-esteem in soon-to-be-mothers might help to enhance the antenatal attachment between mother and the unborn child. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We consider an initial-boundary value problem for the n-dimensional wave equation with the variable sound speed, n ≥ 1 . We construct three-level implicit in time and compact in space (three-point in each space direction) 4th order finite-difference schemes on the uniform rectangular meshes including their one-parameter (for n = 2 ) and three-parameter (for n = 3 ) families. We also show that some already known methods can be converted into such schemes. In a unified manner, we prove the conditional stability of schemes in the strong and weak energy norms together with the 4th order error estimate under natural conditions on the time step. We also transform an unconditionally stable 4th order two-level scheme suggested for n = 2 to the three-level form, extend it for any n ≥ 1 and prove its stability. We also give an example of a compact scheme for non-uniform in space and time rectangular meshes. We also suggest simple and fast (in theory and practice) iterative methods to implement the schemes. A new effective initial guess to start iterations is given too. We also present promising results of a number of various 2D and 3D numerical experiments. [ABSTRACT FROM AUTHOR]

Children and adolescents with complex medical conditions are often uprooted from their environments and isolated in hospital while undergoing treatment. Little is known about how they perceive this isolation and its subsequent impact on their relationships with peers, both during and after isolation for treatment. This study describes the experience of hospital isolation from the perspectives of children and adolescents with a malignant brain tumor. The use and impact of information and communication technologies (ICT) as a possible bridge for contact is also explored. Following a qualitative approach utilizing interpretive phenomenological analysis, in-depth interviews were conducted with eight youth participants who had undergone treatment for medulloblastoma. Data analysis generated three main themes: (1) transforming children and relationships, (2) hospitalization in a digital world, and (3) ICTs as a promising bridge back to school. Study findings provide insight into the experience of hospital isolation for children and adolescents, while highlighting the positive social as well as academic outcomes of frequent, open ended ICT use throughout hospital isolation. This is timely, given the context of the COVID-19 pandemic and its resulting isolation. Considerations for hospital social workers to promote relationships and connection, while facilitating a smooth transition as these children return to school are included. [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]

Purpose: To retrospectively compare interpretations of Doppler ultrasound (US) in newborns with confirmed perinatal testicular torsion (PTT) by an experienced faculty (staff) pediatric radiologist (SPR), pediatric radiology fellow (PRF), pediatric urology fellow (PUF) and staff pediatric urologist (SPU). Methods: US images of 27 consecutive males with PTT between May 2000 and July 2020 were retrieved. The testicles were classified as affected or non-affected by PTT. We performed a blinded comparison of interpretation by four assessors (SPR, PRF, PUF, SPU), with respect to the US features of PTT. Paired inter-rater agreement was calculated using Cohen's Kappa (κ) and overall agreement was assessed using Fleiss' kappa. Results: Overall comparison using Fleiss' kappa found fair agreement for most features except testicular echogenicity and echogenic foci at interface for which there was poor agreement. Paired comparisons revealed better agreement between the SPR and PRF compared to the remaining two pairs, suggesting a need for the pediatric urologists (PUF and SPU) to acquaint themselves with testicular ultrasonography as this may have an impact on patient risk stratification and the quality of information given to parents. Conclusion: This study highlights the need for focused training program for pediatric urologists to attain similar agreement as the radiologists, suggesting a need for the pediatric urologists (PUF and SPU) to acquaint themselves with testicular ultrasonography as this may have an impact on patient risk stratification and the quality of information given to parents. [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]

In this paper, a reduced-order model built from the reduced basis (RB) method is used as a surrogate for an inverse identification problem related to coupled thermo-hydro-mechanical (THM) processes. The RB space—spanned by solutions of the governing THM equations—is constructed using a greedy adaptive procedure guided by an a posteriori error estimator that selects the optimal snapshot points in a given parametric space. The RB model is assessed in terms of accuracy and computational cost reduction for the three-dimensional transient coupled problem described by the ATLAS III small-scale in situ heating test. The substantial system size reduction and the associated significant computational gain result in a surrogate model suitable for parameter identification procedures in the Boom Clay material. The effectiveness of the proposed strategy is demonstrated by performing inverse analysis based on direct-search and genetic algorithm (GA) optimization supported by real sensor measurement data where 800 times faster computational speed-up was achieved. Highlights: •Coupled properties for thermo-hydro-mechanical processes in potential host rock for deep geological repositories are identified by inverse analysis. •Surrogate models are built from model order reduction using a greedy adaptive procedure guided by an a-posteriori error estimator. •Surrogate models result in a significant computational gain while preserving the physics of the coupled system. •Parameters of the host rock formation can be identified from measurement data of in-situ heating test using inverse analysis at a much faster rate. [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]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Early mortality remains a challenging therapeutic facet of the initial induction phase of intensive chemotherapy in patients with acute myeloid leukemia (AML). The impact of standard molecular evaluation and risk category of the European LeukemiaNet (ELN) 2017 classification model on early mortality has not been rigorously evaluated thus far. We reviewed the medical records of 320 consecutive adult patients with newly diagnosed AML treated with intensive induction chemotherapy in our center from 2007 to 2021. The median age was 56 years; 33 patients (10%) died during induction. Patient age, white blood cell count, hemoglobin level, platelet level, creatinine, uric acid, lactate dehydrogenase serum levels, and FLT3-ITD and CEBPA mutational status did not significantly impact early mortality. NPM1mut patients had a lower likelihood of early death compared to NPM1wt (5% versus 13%; p = 0.023) whereas patients with high-risk cytogenetic studies experienced higher rates of induction mortality compared with intermediate and favorable risk patients (20% versus 8 and 7%, respectively; p = 0.049). Adverse risk ELN 2017 was significantly more likely to die during induction compared with intermediate and favorable risk patients (20% versus 10 and 4%, respectively; p = 0.001). Patients treated in 2007–2011 experienced a significantly higher rate of induction death compared with patients in 2012–2021 (17% versus 8%; p = 0.039). Multivariate analysis confirmed adverse ELN 2017 [odds ratio (OR), 6.7; 95% confidence interval (CI), 1.74–25.3; p = 0.006) and treatment timeframe (OR, 0.35; 95% CI, 0.14–0.85; p = 0.019) as pivotal predictors of early mortality. ELN 2017 is a robust prognosticator of early mortality in intensively treated AML patients. [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]

Explicit two-level difference schemes on staggered meshes are studied for two well-known regularizations of 1D barotropic gas dynamics equations, including schemes with discretization in x with the property of total energy dissipation. The criteria for L2-dissipativity in the Cauchy problem are derived for their linearizations on a constant solution with zero background velocity. The criteria for schemes on nonstaggered and staggered meshes are compared. The case of 1D Navier-Stokes equations without an artificial viscosity coefficient is also considered. For one of their regularizations, the maximum time step is guaranteed by the choice of the regularization parameter , where and are the background sound speed and kinematic viscosity; this choice is independent of the meshes. To analyze the case of 1D Navier-Stokes-Cahn-Hilliard equations, the criteria are derived and tested for the L2-dissipativity and stability of an explicit difference scheme for a nonstationary equation of the 4th order in x with a second order term in x. The obtained criteria can be useful in calculating flows at low Mach numbers. [ABSTRACT FROM AUTHOR]

We propose a general method for optimizing periodic input waveforms for global entrainment of weakly forced limit-cycle oscillators based on phase reduction and nonlinear programming. We derive averaged phase dynamics from the mathematical model of a limit-cycle oscillator driven by a weak periodic input and optimize the Fourier coefficients of the input waveform to maximize prescribed objective functions. In contrast to the optimization methods that rely on the calculus of variations, the proposed method can be applied to a wider class of optimization problems including global entrainment objectives. As an illustration, we consider two optimization problems, one for achieving fast global convergence of the oscillator to the entrained state and the other for realizing prescribed global phase distributions in a population of identical uncoupled noisy oscillators. We show that the proposed method can successfully yield optimal input waveforms to realize the desired states in both cases. [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]

Glucocorticoids might have significant influence on positive fluid balance, mostly due to their mineralocorticoid effect. We assessed the association between glucocorticoid therapy and fluid balance in septic patients, in the intensive care unit (ICU). We considered two definitions of exposure: daily exposure to glucocorticoids and glucocorticoid treatment at any time. Of 945 patients, 375 were treated with glucocorticoids in the ICU. We applied four regression models. In the first, fluid balance did not differ during days with and without glucocorticoid treatment, among patients treated and not treated with glucocorticoids in the ICU. In our second model, daily fluid balance was increased in patients who were ever treated with glucocorticoids during their ICU stay compared to untreated patients. In the third model, which included only patients treated with glucocorticoids during their ICU stay, glucocorticoid treatment days were not associated with daily fluid balance. In the last model, on "steroid-free days", patients who received glucocorticoid treatment during their ICU stay had a positive fluid balance compared to those who were never treated with steroids. Despite their known mineralocorticoid activity, glucocorticoids themselves appear not to contribute substantially to fluid retention. This work highlights the importance of precise selection of variables to mitigate biases. [ABSTRACT FROM AUTHOR]

We construct a new spatial finite-difference discretization for a regularized 3D Navier–Stokes–Cahn–Hilliard system of equations. The system can be attributed to phase field type models and describes flows of a viscous compressible isothermal two-component two-phase fluid with surface effects; the potential body force is also taken into account. In the discretization, the main sought functions are defined on one and the same mesh, and an original approximation of the solid wall boundary conditions (homogeneous with the discretization of equations) is suggested. The discretization has an important property of the total energy dissipativity allowing one to eliminate completely the so-called spurious currents. The discrete total mass and component mass conservation laws hold as well, and the discretization is also well-balanced for the equilibrium solutions. To ensure that the concentration C remains within the physically meaningful interval (0, 1), the non-convex part of the Helmholtz free energy is taken in a special logarithmic form (the Flory–Huggins potential). The speed of sound can depend on C that leads to different equilibrium mass densities of the "pure" phases. The results of numerical 3D simulations are also presented including those with a gravitational-type force. The positive role of the relaxation parameter is discussed too. [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]

Purpose: Dynamic changes in urine output and neurological status are the recognized clinical signs of hemodynamically significant hemorrhage. In the present study, we analyzed the dynamic minute-to-minute changes in the UFR and also the changes in its minute-to-minute variability in a group of critically ill multiple trauma patients whose blood pressures were normal on admission to the ICU but who subsequently developed hypotension within the first few hours of their ICU admission. Patients and methods: The study was retrospective and observational. Demographic and clinical data were extracted from the computerized register information systems initially; the clinical and laboratory data of 100 critically ill patients with multiple trauma who were admitted to the ICU during the study period were analyzed. Of this group, ten patients were eventually included in the study on the basis of the inclusion criteria. Results: The minute-to-minute urine flow rate (UFR) and urine flow rate variability (UFRV) both decreased significantly during the periods of hypotension (p values 0.001 and 0.006, respectively). Notably, the decrease in UFRV preceded by at least 30 min a corresponding decline in the systolic and mean arterial blood pressures, which manifested as a flattening of UFRV amplitude which was observed prior to the occurrence of the lowest recorded systolic and mean arterial blood pressures. Statistical analysis by the Pearson method demonstrated a strong direct correlation between the decrease in UFRV and the decrease in the MAP (R = 0.9, p = 0.001), and SBP (R = 0.86, p = 0.001) and the decreasing urine output per hour (R = 0.88, p < 0.001). Conclusion: We found that changes in UFRV correlate strongly with systolic and mean arterial blood pressures. We feel that this parameter could potentially serve as an early signal of hemodynamic deterioration due to occult bleeding in critically ill trauma patients, and might also be able to identify the optimal end-point of hemodynamic resuscitative measures in these patients. [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]

Oceanic crustal accretion at mid-ocean ridges is a function of spreading rate, mantle temperature, and composition, which are intertwined in affecting melt production and oceanic crustal thickness. Sparse and irregular seismic and geochemical observations on a global scale showed no correlation between crustal thickness and spreading rate along slow to fast-spreading centers. Here, we compile a global oceanic crustal thickness model from gravity data to revisit this issue at a high resolution. Gravity-observed melt volume shows a positive correlation with spreading rate globally, implying that spreading rate is the dominant factor in melt production. However, oceanic crustal thickness is negatively correlated with spreading rate from slow to fast-spreading centers, and this trend is further consolidated by the increase in Curie point depth (a geothermal proxy) and ridge depth with increasing spreading rate. Thus, a decreasing near-ridge temperature probably contributes to crustal thinning from slow to fast-spreading centers. Inferred low melt volume anomalies beneath fast-spreading centers are consistent with a 20 °C temperature drop in the near-ridge mantle, likely caused by efficient hydrothermal cooling. [ABSTRACT FROM AUTHOR]

In its original conception, proper generalized decomposition (PGD) provides explicit parametric solutions, denoted as computational vademecums or digital abacuses, to parametric boundary value problems. The PGD approach is extended here to devise a set of algebraic tools enabling to operate with multidimensional tensor data. These tools are designed to store, compress and perform basic operations (in particular divisions) with tensors in separable format. These tools are directly producing the computational vademecums for the resulting high-dimensional tensor data. Thus, the general methodology enables performing nontrivial operations (storage, compression, division, solving linear systems of equations...) for multidimensional tensor data. The idea is based on the principle of the PGD separation, that produces a separable least squares approximation of any multidimensional function. The PGD compression is a particular case, extensively used in practice to compact the separable solution without loss of accuracy. Here, this concept is applied to algebraic tensor structures that are also seen as functions in multidimensional Cartesian domains. Moreover, a straightforward extension of this concept is devised to operate with multidimensional objects stored in the separable format. That allows creating a toolbox of PGD arithmetic operators that is publicly released at https://git.lacan.upc.edu/zlotnik/algebraicPGDtools. Numerical tests demonstrate the performance and efficiency of the toolbox, both for tensor data handling and operation and also in applications pertaining to the discretized version of boundary value problems. [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]

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]

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]

Anthropogenic factors, including the spread of endocrine-disrupting chemicals, have been linked to alterations in the reproductive physiology, morphology, and behavior of wildlife. Few studies of endocrine disruption, however, focus on secondary sexual traits that affect mating signals, despite their importance for reproductive success. The larynx of many anurans (frogs and toads), for example, is larger in males than in females and is crucial for producing mating calls. We aim to determine if wild populations of cane toads (Rhinella marina) near sugarcane fields in Florida have demasculinized larynges when compared to populations near urban areas. We find evidence of demasculinization in both primary and secondary sexual traits in male toads living near sugarcane. Relative to body size, the laryngeal mass, vocal cord length, and dilator muscle width are all reduced in males from sugarcane regions compared to their urban counterparts. Strong correlations between primary and secondary male sexual traits indicate that demasculinization occurs in concert both within and across diverse organs, including the testes, larynx, and skin. Our results show that anurans near sugarcane fields have demasculinized reproductive systems, that this disruption extends to secondary sexual traits like the larynx, and that it is likely due to anthropogenic causes. [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]

Fast direct and inverse algorithms for expansion in terms of eigenvectors of one-dimensional eigenvalue problems for a high-order finite element method (FEM) are proposed based on the fast discrete Fourier transform. They generalize logarithmically optimal Fourier algorithms for solving boundary value problems for Poisson-type equations on rectangular meshes to high-order FEM. The algorithms can be extended to the multidimensional case and can be applied to nonstationary problems. [ABSTRACT FROM AUTHOR]

Introduction: Treatment of combined traumatic brain injury and hemorrhagic shock, poses a particular challenge due to the possible conflicting consequences. While restoring diminished volume is the treatment goal for hypovolemia, maintaining adequate cerebral perfusion pressure and avoidance of secondary damage remains a treatment goal for the injured brain. Various treatment modalities have been proposed, but the optimal resuscitation fluid and goals have not yet been clearly defined. A growing body of evidence suggests that in hypovolemic shock, resuscitation with fresh whole blood (FWB) may be superior to component therapy without platelets (which are likely to be unavailable in the pre-hospital setting). Nevertheless, the effects of this approach have not been studied in the combined injury. Previously, in a rat model of combined injury we have found that mild resuscitation to MABP of 80 mmHg with FWB is superior to fluid resuscitation or aggressive resuscitation with FWB. In this study, we investigate the physiological and neurological outcomes in a rat model of combined traumatic brain injury (TBI) and hypovolemic shock, submitted to treatment with varying amounts of FWB, compared to similar resuscitation goals with fractionated blood products—red blood cells (RBCs) and plasma in a 1:1 ratio regimen. Materials and methods: 40 male Lewis rats were divided into control and treatment groups. TBI was inflicted by a free-falling rod on the exposed cranium. Hypovolemia was induced by controlled hemorrhage of 30% blood volume. Treatment groups were treated either with fresh whole blood or with RBC + plasma in a 1:1 ratio, achieving a resuscitation goal of a mean arterial blood pressure (MAP) of 80 mmHg at 15 min. MAP was assessed at 60 min, and neurological outcomes and mortality in the subsequent 24 h. Results: At 60 min, hemodynamic parameters were improved compared to controls, but not significantly different between treatment groups. Survival rates at 48 h were 100% for both of the mildly resuscitated groups (MABP 80 mmHg) with FWB and RBC + plasma. The best neurological outcomes were found in the group mildly resuscitated with FWB and were better when compared to resuscitation with RBC + plasma to the same MABP goal (FWB: Neurological Severity Score (NSS) 6 ± 2, RBC + plasma: NSS 10 ± 2, p = 0.02). Conclusions: In this study, we find that mild resuscitation with goals of restoring MAP to 80 mmHg (which is lower than baseline) with FWB, provided better hemodynamic stability and survival. However, the best neurological outcomes were found in the group resuscitated with FWB. Thus, we suggest that resuscitation with FWB is a feasible modality in the combined TBI + hypovolemic shock scenario, and may result in improved outcomes compared to platelet-free component blood products. [ABSTRACT FROM AUTHOR]

Explicit two-level in time and symmetric in space difference schemes constructed by approximating the 1D barotropic quasi-gas-/quasi-hydrodynamic systems of equations are studied. The schemes are linearized about a constant solution with a nonzero velocity, and, for them, necessary and sufficient conditions for the -dissipativity of solutions to the Cauchy problem are derived depending on the Mach number. These conditions differ from one another by at most twice. The results substantially develop the ones known for the linearized Lax–Wendroff scheme. Numerical experiments are performed to analyze the applicability of the found conditions in the nonlinear formulation to several schemes for different Mach numbers. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing processes are surrounded by uncertainty, as available data is typically scant. In this work, we present a sampling-based stochastic analysis of the hydraulic fracturing process by considering various system parameters to be random. Our analysis is based on the Perkins-Kern-Nordgren (PKN) model for hydraulic fracturing. This baseline model enables computation of high fidelity solutions, which avoids pollution of our stochastic results by inaccuracies in the deterministic solution procedure. In order to obtain the desired degree of accuracy of the computed solution, we supplement the employed time-dependent moving-mesh finite element method with two new enhancements: (i) global conservation of volume is enforced through a Lagrange multiplier; (ii) the weakly singular behavior of the solution at the fracture tip is resolved by supplementing the solution space with a tip enrichment function. This tip enrichment function enables the computation of the tip speed directly from its associated solution coefficient. A novel incremental-iterative solution procedure based on a backward-Euler time-integrator with sub-iterations is employed to solve the PKN model. Direct Monte-Carlo sampling is performed based on random variable and random field input parameters. The presented stochastic results quantify the dependence of the fracture evolution process—in particular the fracture length and fracture opening—on variations in the elastic properties and leak-off coefficient of the formation, and the height of the fracture. [ABSTRACT FROM AUTHOR]

Social services are instrumental in addressing challenges associated with aging. Yet, practitioners report needing expanded gerontological knowledge and better supervision. The Supervisory Leaders in Aging (SLA) program of the National Association of Social Workers (NASW) was designed to improve gerontological services by strengthening supervision of the social service workforce. With support from the John A. Hartford Foundation, the program was adopted between 2015 and 2017 in four regions, where NASW trained 134 MSW supervisors who support 1200 social service staff, potentially enhancing the well-being of 264,000 clients annually. The SLA curriculum and in-person educational approach constitute a model for supervisor professional development. Quality improvement evaluations suggested feasibility of program adoption and acceptability. Participants rated each of 10 workshops and 97% agreed that instructors were effective, that knowledge was expanded, and that content was relevant, appropriate, and likely to be used. Implications of this model for enhancing supervisory practice are discussed. [ABSTRACT FROM AUTHOR]

An explicit two-level in time and spatially symmetric finite-difference scheme approximating the 1D quasi-gasdynamic system of equations is studied. The scheme is linearized about a constant solution, and new necessary and sufficient conditions for the L2-dissipativity of solutions to the Cauchy problem are derived, including, for the first time, the case of a nonzero background velocity and depending on the Mach number. It is shown that the condition on the Courant number can be made independent of the Mach number. The results provide a substantial development of the well-known stability analysis of the linearized Lax-Wendroff scheme. [ABSTRACT FROM AUTHOR]