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In this work, we present an alternative approach to obtain a solenoidal Lipschitz truncation result in the spirit of D. Breit, L. Diening and M. Fuchs [Solenoidal Lipschitz truncation and applications in fluid mechanics. J. Differ. Equ. 253 (2012), 1910–1942.]. More precisely, the goal of the truncation is to modify a function $u \in W^{1,p}(\mathbb {R}^N;\mathbb {R}^N)$ that satisfies the additional constraint $\operatorname {div} u=0$, such that its modification $\tilde {u}$ is Lipschitz continuous and divergence-free. This approach is different to the approaches outlined in the aforementioned work and D. Breit, L. Diening and S. Schwarzacher [Solenoidal Lipschitz truncation for parabolic PDEs. Math. Models Methods Appl. Sci. 23 (2013), 2671–2700, Section 4] and is able to obtain the rather strong bound on the difference between $u$ and $\tilde {u}$ from the former article. Finally, we outline how the approach pursued in this work may be generalized to closed differential forms.
An orthogonally oriented microstrip-fed bi-element ultra-wideband (UWB) diversity antenna possessing a super-wide bandwidth, high isolation, and band rejection attributes is proposed. The intended diversity antenna uses a 2nd-order Cayley fractal tree-shaped neutralization line among a pair of radiating square monopoles along with additional components like extended ground stubs, hybrid Koch fractal parasitic elements, and an L-shaped defected ground structure to attain high isolation of <−20 dB over 3.1–18 GHz. To nullify the intervention from the existent wireless local area network band, a hybrid Koch–Minkowski slot is carved out from the radiators. A minimal inter-element spacing of 8 mm is attained with the suggested layout measuring 28 mm (L) × 42 mm (W) in extent. The numerical as well as experimental investigations of vital diversity attributes like the envelope correlation coefficient, mean effective gain, total active reflection coefficient, and multiplexing efficiency depict high diversity actualization. The consistency amidst the simulation as well as the empirical results recommends the worthiness of the intended antenna for handy UWB and UWB multiple-input multiple-output systems.
This paper is devoted to the structural stability of a transonic shock passing through a flat nozzle for two-dimensional steady compressible flows with an external force. We first establish the existence and uniqueness of one-dimensional transonic shock solutions to the steady Euler system with an external force by prescribing suitable pressure at the exit of the nozzle when the upstream flow is a uniform supersonic flow. It is shown that the external force helps to stabilize the transonic shock in flat nozzles and the shock position is uniquely determined. Then we are concerned with the structural stability of these transonic shock solutions when the exit pressure is suitably perturbed. One of the new ingredients in our analysis is to use the deformation-curl decomposition to the steady Euler system developed by Weng and Xin [Sci. Sinica Math., 49 (2019), pp. 307–320] to deal with the transonic shock problem.
Unilateral absence of intra-pericardial pulmonary artery is a rare congenital malformation. If untreated, it can lead to morbidity and mortality in adulthood. Early intervention and restoration of physiologic pulmonary blood flow is necessary. Transcatheter stenting as initial intervention has been rarely reported. We present transcatheter recanalisation and stenting of the obliterated ductus in two newborns with unilateral absence of intra-pericardial pulmonary artery with cross-sectional imaging, procedural details, angiography, and follow up to surgical repair. We believe that such procedure promotes ipsilateral pulmonary vasculature growth to facilitate unifocalization surgery at a later age.
Cathodes with recessed sample surfaces have several benefits in cesium sputter ion sources, including higher output, more efficient use of sample material, and improved focusing of the extracted ion beam. However, the Ionplus MICADAS uses cathodes with a graphite surface that is essentially flush with the sample holder. To evaluate the performance of recessed graphite with the MICADAS and determine the optimal surface depth, we tested four different depths, including the standard (flush) pressing method, 0.5 mm, 1.0 mm, and 1.5 mm. We found that recessed depths of 1.0 and 1.5 mm resulted in 20% higher ion beam current compared to the standard method under the same source conditions. The results are consistent with the beam produced from the recessed targets being more narrowly focused with a lower emittance, resulting in better transmission through the accelerator. Small graphite samples (200 µg C) with recessed surfaces produced higher currents for longer, leading to a 2–3× increase in sample ionization efficiency. Additionally, there was some evidence that isotopic ratio measurements of recessed samples were more stable over time. Overall, samples recessed to 1 mm depth offered numerous advantages over the standard pressing method and we have subsequently started pressing all MICADAS graphite using this approach.
This article examines the politics of music at the Carlisle Indian Industrial School, the flagship federal off-reservation boarding school for the compulsory education of Indigenous children, established in Carlisle, Pennsylvania, in 1879. By examining the music education and performance culture at the Carlisle School, this article considers the role of music both within boarding school discourses of “civilization” and in terms of the larger federal goal of dispossession of Native land. Based on original archival research and engagements with contemporary discourses in Indigenous music and sound studies, the article then considers a nationalistic comic opera titled The Captain of Plymouth performed by Native students at the Carlisle commencement exercises in 1909. It argues ultimately that, although music, dance, and expressive culture were a central concern for federal assimilationist policy, music making at Carlisle provided a groundwork for the emergence of an intertribal social formation that guided musical practices and self-determination movements of the twentieth and twenty-first centuries.
Gymnocranius indicus sp. nov. is described as a new species of the fish subfamily Monotaxinae (Sparoidea: Lethrinidae), a group of commercially important species distributed throughout the Indo-West Pacific, on the basis of 16 specimens collected from the Indian Ocean. The new species shares the following characters with its western Pacific sibling, the eyebrowed large-eye seabream, G. superciliosus: elongate body, distinctive and conspicuous dark patch above the eye, prominent forehead, moderately forked caudal fin, its lobes slightly convex inside, flank silvery, and reddish-to-red dorsal, pectoral, anal and caudal fins. However, principal component analysis based on seven morphological variables distinguished most specimens from the Indian Ocean from G. superciliosus. The most influential variable in the analysis was the eye diameter, significantly larger in the new species than in G. superciliosus. All specimens of the new species that were examined also lacked blue ornamentation on the snout and cheek. At the mitochondrial cytochrome oxidase subunit-I locus, the mean genetic p-distance between the two species was 0.039. With Gymnocranius indicus sp. nov., the genus now includes 12 valid nominal species; three additional species remain undescribed.
States and interest groups are facilitating a redistribution of government powers under a new courts-first federalism. States are working to claw back powers while interest groups drafting model laws strategically tailor them to skirt the limits of federal law and, once adopted by states, prompt federal courts to review them as parties litigate to clarify their rights. States do not need to be completely successful in litigation to shift the balance of state–national power. Testing this argument, we find that the US Supreme Court grants review to 17% of model laws in our sample produced by the American Legislative Exchange Council (ALEC), whereas merely 1% of other cases are granted certiorari. Ultimately, the states and ALEC were partly successful in constraining federal power. Thus, the combination of model legislation, impact litigation, and courts-first federalism becomes a tool for states to draw power to themselves and from the federal government.
Philosophers traditionally interpret Kant as a retributivist, but modern interpreters, with reference to Kant’s theory of justice and problematic passages, instead propose penal theories that mix retributive and deterrent features. Although these mixed penal theories are substantively compelling and capture the Kantian spirit, their dual aspects lead to a justificatory conflict that generates an apparent dilemma. To resolve this dilemma and clear the ground for these mixed theories, I will outline and reinterpret Kant’s penal theory by situating it in his broader moral and political philosophy. This move grounds the followability requirement, which is necessary to resolve the dilemma.
We show that the mode-locking region of the family of quasi-periodically forced Arnold circle maps with a topologically generic forcing function is dense. This gives a rigorous verification of certain numerical observations in [M. Ding, C. Grebogi and E. Ott. Evolution of attractors in quasiperiodically forced systems: from quasiperiodic to strange nonchaotic to chaotic. Phys. Rev. A39(5) (1989), 2593–2598] for such forcing functions. More generally, under some general conditions on the base map, we show the density of the mode-locking property among dynamically forced maps (defined in [Z. Zhang. On topological genericity of the mode-locking phenomenon. Math. Ann.376 (2020), 707–72]) equipped with a topology that is much stronger than the $C^0$ topology, compatible with smooth fiber maps. For quasi-periodic base maps, our result generalizes the main results in [A. Avila, J. Bochi and D. Damanik. Cantor spectrum for Schrödinger operators with potentials arising from generalized skew-shifts. Duke Math. J.146 (2009), 253–280], [J. Wang, Q. Zhou and T. Jäger. Genericity of mode-locking for quasiperiodically forced circle maps. Adv. Math.348 (2019), 353–377] and Zhang (2020).
The Canadian child welfare system has been characterized as being in crisis for over a decade; the number of children in care (and dying in care) has increased dramatically, straining an overburdened system. Physical or sexual abuse is not the reason most children are removed from their homes; rather, the state deems them lacking the necessities of life, usually because their family is impoverished. Because the majority of children in care are Indigenous, the child welfare system is described as the new version of residential schools. Using the lens of historical institutionalism, this study argues that the current child welfare system reflects colonial and neoliberal assumptions that some parents are incapable of sound decision making by virtue of their race or socio-economic situation. Canada's child welfare system is both a product and contributor to the institutions and policies that reinforce intergenerational poverty, a key determinant of removing children from their families.
Malignant vasovagal syncope in children seriously affects their physical and mental health. Our study aimed to explore the efficacy of catheter ablation in ganglionated plexus with malignant vasovagal syncope children.
Conclusion:
Catheter ablation of ganglionated plexus was safe and effective in children with malignant vasovagal syncope and can be used as a treatment option for these children.
Methods:
A total of 20 children diagnosed with malignant vasovagal syncope were enrolled in Beijing Children’s Hospital, affiliated with Capital Medical University. All underwent catheter ablation treatment of ganglionated plexus. Ganglionated plexuses of the left atrium were identified by high-frequency stimulation and/or anatomic landmarks being targeted by radiofrequency catheter ablation. The efficacy of the treatment was evaluated by comparing the remission rate of post-operative syncopal symptoms and the rate of negative head-up tilt results. Safety and adverse events were evaluated.
Results:
After follow-up for 2.5 (0.6–5) years, the syncope symptom scores were decreased significantly compared with before treatment [3 (2–4) versus 5 (3–8) scores, P < 0.01]. Eighty-five per cent (17/20) children no longer experienced syncope, whilst 80% (16/20) children showed negative head-up tilt test after treatment. No adverse effects such as cardiac arrhythmia occurred in the children.
Social policy scholars seeking to understand the dynamics of social protection arrangements have advocated for an actor-centric approach. However, when seeking to understand the impact of colonialism on social policymaking, most scholars have focused not on actors but on ideas and institutions. To address this gap, this paper develops an actor-centric framework for understanding the introduction of social policies in colonial contexts. We identify and compare actor constellations of relevance to the introduction of social policies in two colonies of French West Africa that differ with respect to precolonial population density: Dahomey (present-day Benin), with a relatively high precolonial population density, and Côte d’Ivoire, with a relatively low precolonial population density. Despite evidence that precolonial population density can shape colonial strategies and policies, the results provide no supporting evidence that precolonial population density is a driver of meaningful variation in the introduction of social policies or in the composition of the actor constellations from which they originate. Instead, the results point to the key role of transnational and regional actors in the introduction of social policies in colonial contexts. They also highlight the domestic economic and societal arenas as sites where: i) heterogeneity emerges in the social policy actor constellations; and ii) local actors mediate tensions arising from imperially driven social transformations.
The geostrophic turbulence in rapidly rotating thermal convection exhibits characteristics shared by many highly turbulent geophysical and astrophysical flows. In this regime, the convective length and velocity scales and heat flux are all diffusion-free, i.e. independent of the viscosity and thermal diffusivity. Our direct numerical simulations (DNS) of rotating Rayleigh–Bénard convection in domains with no-slip top and bottom and periodic lateral boundary conditions for a fluid with the Prandtl number $Pr=1$ and extreme buoyancy and rotation parameters (the Rayleigh number up to $Ra=3\times 10^{13}$ and the Ekman number down to $Ek=5\times 10^{-9}$) indeed demonstrate all these diffusion-free scaling relations, in particular, that the dimensionless convective heat transport scales with the supercriticality parameter $\widetilde {Ra}\equiv Ra\, Ek^{4/3}$ as $Nu-1\propto \widetilde {Ra}^{3/2}$, where $Nu$ is the Nusselt number. We further derive and verify in the DNS that with the decreasing $\widetilde {Ra}$, the geostrophic turbulence regime undergoes a transition into another geostrophic regime, the convective heat transport in this regime is characterized by a very steep $\widetilde {Ra}$-dependence, $Nu-1\propto \widetilde {Ra}^{3}$.
Radiocarbon and uranium-thorium dating of microbialites and penecontemporaneous cements in a microbialite mound at Death Point at Lakeside, Utah, on the shore of Great Salt Lake, Utah, call for a revision of the Lake Bonneville hydrograph. At about 30,000 cal yr BP, the lake experienced an abrupt rise of about 20 m, then dropped back down to levels near or slightly higher than the modern average elevation of Great Salt Lake. Over the ensuing ~6000 yr the lake experienced a series of fluctuations, up to levels a few tens of meters higher than the modern average Great Salt Lake, then down again. The exact timing and amplitudes of those fluctuations are not known, but importantly, the lake did not rise to levels near the Stansbury shoreline (~80 m higher than Great Salt Lake) until after about 24,000 cal yr BP. After the Stansbury shoreline, the lake rose almost 200 m to its highest level at the Bonneville shoreline by about 17,500 cal yr BP. This interpretation is different from previously published hydrographs, many of which show a relatively steady rise to near the Stansbury shoreline between 30,000 and 25,000 cal yr BP.