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In the ninth century AD, Moravia (now in Czechia) was the heartland of the first Slavic state-like formation in Central Europe. Traditionally, the archaeology of the region has been interpreted via historical records only; the FORMOR project aims to broaden this view by using archaeometry, archaeogenetics, bioarchaeology and introducing new theoretical approaches.
Social investment can act as an empowering funding mechanism that could activate the economic agency of marginalised people while addressing their social needs. Nonetheless, political agendas might cause divergence in the achievement of social investment’s potential benefits. To develop our understanding in this area, this paper aims to extract discursive policy framings of social investment by comparing the UK and Scottish Government policies to identify the use of social investment and its implications on social innovation. Using corpus linguistic methods that allows for a framing analysis, the paper’s findings are twofold. Firstly, both the UK and Scottish Governments share similarities in the framing of social investment policy, especially in the proclivity towards the privatisation of social welfare delivery using market mechanisms. Secondly, the governments differ in their intensity of conviction for social investment which creates divergent implications for social innovation practice in the countries.
With the rise of online references, podcasts, webinars, self-test tools, and social media, it is worthwhile to understand whether textbooks continue to provide value in medical education, and to assess the capacity they serve during fellowship training.
Methods:
A prospective mixed-methods study based on surveys that were disseminated to seven paediatric cardiology fellowship programmes around the world. Participants were asked to read an assigned chapter of Anderson’s Pediatric Cardiology 4th Edition textbook, followed by the completion of the survey. Open-ended questions included theming and grouping responses as appropriate.
Results:
The survey was completed by 36 participants. When asked about the content, organisation, and utility of the chapter, responses were generally positive, at greater than 89%. The chapters, overall, were rated relatively easy to read, scoring at 6.91, with standard deviations plus or minus 1.72, on a scale from 1 to 10, with higher values meaning better results. When asked to rank their preferences in where they obtain educational content, textbooks were ranked the second highest, with in-person teaching ranking first. Several themes were identified including the limitations of the use of textbook use, their value, and ways to enhance learning from their reading. There was also a near-unanimous desire for more time to self-learn and read during fellowship.
Conclusions:
Textbooks are still highly valued by trainees. Many opportunities exist, nonetheless, to improve how they can be organised to deliver information optimally. Future efforts should look towards making them more accessible, and to include more resources for asynchronous learning.
We define duality triples and duality pairs in compactly generated triangulated categories and investigate their properties. This enables us to give an elementary way to determine whether a class is closed under pure subobjects, pure quotients and pure extensions, as well as providing a way to show the existence of approximations. One key ingredient is a new characterization of phantom maps. We then introduce an axiomatic form of Auslander–Gruson–Jensen duality, from which we define dual definable categories, and show that these coincide with symmetric coproduct closed duality pairs. This framework is ubiquitous, encompassing both algebraic triangulated categories and stable homotopy theories. Accordingly, we provide many applications in both settings, with a particular emphasis on silting theory and stratified tensor-triangulated categories.
Consider the motion of a thin layer of electrically conducting fluid, between two closely spaced parallel plates, in a classical Hele-Shaw geometry. Furthermore, let the system be immersed in a uniform external magnetic field (normal to the plates) and let electrical current be driven between conducting probes immersed in the fluid layer. In the present paper, we analyse the ensuing fluid flow at low Hartmann numbers. Physically, the system is particularly interesting because it allows for circulation in the flow, which is not possible in the standard pressure-driven Hele-Shaw cell. We first elucidate the mechanism of flow generation both physically and mathematically. After formulating the problem using complex variables, we present mathematical solutions for a class of canonical multiply connected geometries in terms of the prime function framework developed by Crowdy (Solving Problems in Multiply Connected Domains, SIAM, 2020). We then demonstrate how recently developed fast numerical methods may be applied to accurately determine the flow field in arbitrary geometries.
This introduction develops a theoretical framework for understanding authoritarian backsliding against the backdrop of existing historical and European socio-legal scholarship. It introduces a number of key distinctions to better understand socio-legal variance among autocratisation. Specifically, it highlights the distinction between authoritarian backsliding and complete breakdown of judicial independence and human rights
Authoritarian backsliding is an aggravated form of rule of law decay, where functioning of key rule of law institutions comes under direct threat and it is mostly observable in the contemporary Central and Eastern European context. This differs from historical instances of authoritarian turn referring to the complete breakdown of judicial independence and human rights, characterised by the politicisation of courts as a mainly historical phenomenon. The differentiation and their socio-legal implications is crucial for developing a roadmap to identify different forms of autocratisation and their different contexts (actors, institutional and political context) that need to be considered when addressing rule of law decay in Europe, both at the national and supranational levels. Ultimately, this general overview also offers the possibility to identify and address latent discontinuities in rule of law development at both the supranational and national levels. Identification of such latent discontinuities is of importance when assessing the risks involved in the introduction of emergency measures to combat perceived threats to the state and the society.
Bluff-body wakes generally become three-dimensional (3-D) and then turbulent when the Reynolds number exceeds a few hundred. Other than an alternate shedding of the spanwise vortices behind the body and a gradual decay and annihilation of the vortices with distance downstream, whether a secondary vortex street would develop in the relatively far wake has been a long-standing argument in the literature. This argument is addressed in the present study. Specifically, direct numerical simulations and transient growth analysis are performed to examine the two-dimensional and 3-D wakes of different bluff bodies, including circular cylinder, square cylinder, diamond cylinder and rectangular cylinders with different cross-sectional aspect ratios. We found that a secondary vortex street is absent for most 3-D and turbulent wakes. The root cause is the weakening of spanwise vortices by 3-D wake instability modes and streamwise circulation/vorticity. The weakened spanwise vortices induce reduced mean shear in the intermediate wake, which then induces much smaller perturbation energy growth that is below the threshold for the emergence of a secondary vortex street. This finding suggests that the 3-D and turbulence characteristics, and the momentum, mass and heat transport in the relatively far wake of bluff bodies, would not be influenced by extra anisotropy or inhomogeneity caused by a secondary vortex street.
Diffuse interface models are an important class of models used to describe multi-phase flows. In the case of incompressible viscous fluids there are a number of different diffuse interface models which have been known for many years. Nevertheless, a model based on mixture theory with a full set of conservation laws for the conservation of linear momentum of each constituent was not yet available. This gap was filled by ten Eikelder et al. (J. Fluid Mech., in press) recently and a first comparison with known models of Navier–Stokes/Cahn–Hilliard type is given. A detailed understanding of the relations between these models remains an important question.
Liquid metal buoyant flow around two differentially heated horizontal cylinders in the presence of a uniform vertical magnetic field is investigated experimentally. While magneto-convection in pipes or ducts has been studied theoretically and experimentally in recent years, data for heat transfer at immersed obstacles are rare and, to our knowledge, detailed experimental investigations on this fundamental magnetohydrodynamic problem do not exist. In the present work, two horizontal cylinders inserted into an adiabatic rectangular cavity filled with gallium–indium–tin are kept at constant temperatures to establish a driving temperature gradient in the surrounding liquid metal. The buoyancy-driven flow, quantified by the Grashof number $Gr$, is varied in the range ${10^{6} \leq Gr \leq ~5\times 10^{7}}$. With increasing magnetic field, expressed via the Hartmann number $Ha$, different flow regimes are identified from measurements for $0 \leq Ha \leq ~3000$. The effect of the electromagnetic force primarily consists in suppressing turbulence and damping the convective flow. The heat transfer is quantified in terms of the non-dimensional Nusselt number $Nu$, and its dependence on $Gr/{Ha}^{2}$, which is identified as the important group governing the flow, is discussed.
In this essay I read debates about amenities of water and waste in the British Caribbean in the late and immediate post-Victorian period through histories of intimacy and kinship centered in fiction by Caribbean writers of the last twenty years. In these novels and short stories, collecting water at a stream or a standpipe or emptying a chamber pot are actions that produce or recall moments of desire and aspiration, shame and punishment, in storylines that move between a past of enslavement and indentureship in the eighteenth and nineteenth centuries and a present of political and psychological stasis or upheaval in the 1950s, 1970s, or the early twenty-first century. Nineteenth-century discussions about fire hydrants or standpipes index a British Caribbean colony's evolving landscape of modernization and the disagreements about what shape and speed this process should take, and recent fiction allows us to discern how these amenities inherit and bequeath associations of trauma.
Autonomous exploration in unknown environments has become a critical capability of mobile robots. Many methods often suffer from problems such as exploration goal selection based solely on information gain and inefficient tour optimization. Recent reinforcement learning-based methods do not consider full area coverage and the performance of transferring learned policy to new environments cannot be guaranteed. To address these issues, a dual-stage exploration method has been proposed, which combines spatial clustering of possible exploration goals and Traveling Salesman Problem (TSP) based tour planning on both local and global scales, aiming for efficient full-area exploration in highly convoluted environments. Our method involves two stages: exploration and relocation. During the exploration stage, we introduce to generate local navigation goal candidates straight from clusters of all possible local exploration goals. The local navigation goal is determined through tour planning, utilizing the TSP framework. Moreover, during the relocation stage, we suggest clustering all possible global exploration goals and applying TSP-based tour planning to efficiently direct the robot toward previously detected but yet-to-be-explored areas. The proposed method is validated in various challenging simulated and real-world environments. Experimental results demonstrate its effectiveness and efficiency. Videos and code are available at https://github.com/JiatongBao/exploration.
We perform linear stability analysis and direct numerical simulations to study the effect of the radius ratio on the instability and flow characteristics of the sheared annular centrifugal Rayleigh–Bénard convection, where the cold inner cylinder and the hot outer cylinder rotate with a small angular velocity difference. With the shear enhancement, the thermal convection is suppressed and finally becomes stable for different radius ratios $\{\eta \in \mathbb {R}|0.2\leqslant \eta \le 0.95\}$. Considering the inhomogeneous distribution of shear stresses in the base flow, a new global Richardson number $Ri_g$ is defined and the marginal-state curves for different radius ratios are successfully unified in the parameter domain of $Ri_g$ and the Rayleigh number $Ra$. The results are consistent with the marginal-state curve of the wall-sheared classical Rayleigh–Bénard convection in the streamwise direction, demonstrating that the basic stabilization mechanisms are identical. Moreover, systems with small radius ratios exhibit greater geometric asymmetry. On the one hand, this results in a smaller equivalent aspect ratio for the system, accommodating fewer convection roll pairs; fewer roll pairs are more likely to cause a transition in the flow structure during shear enhancement. On the other hand, the shear distribution is more inhomogeneous, allowing for an outward shift of the convection region and the elevation of bulk temperature under strong shear.
A monic polynomial $f(x)\in {\mathbb Z}[x]$ of degree N is called monogenic if $f(x)$ is irreducible over ${\mathbb Q}$ and $\{1,\theta ,\theta ^2,\ldots ,\theta ^{N-1}\}$ is a basis for the ring of integers of ${\mathbb Q}(\theta )$, where $f(\theta )=0$. We prove that there exist exactly three distinct monogenic trinomials of the form $x^4+bx^2+d$ whose Galois group is the cyclic group of order 4. We also show that the situation is quite different when the Galois group is not cyclic.
According to Charles Travis, Frege’s principle to “always to sharply separate the psychological from the logical, the subjective from the objective” involves a move called “the fundamental abstraction.” I try to explain what this abstraction is and why it is interesting. I then raise a problem for it, and describe what I think is a better way to understand Frege’s principle.
Single-flagellated bacteria are ubiquitous in nature. They exhibit various swimming modes using their flagella to explore complex surroundings such as soil and porous polymer networks. Some single-flagellated bacteria swim with two distinct modes, one with the flagellum extended away from its body and another with the flagellum wrapped around it. The wrapped mode has been observed when bacteria swim under tight confinements or in highly viscous polymeric melts. In this study we investigate the hydrodynamics of these two modes inside a circular pipe. We find that the wrapped mode is slower than the extended mode in bulk but more efficient under strong confinement due to a hydrodynamic increase of its flagellum translation–rotation coupling and an Archimedes’ screw-like configuration that helps to move the fluid along the pipe.
Lack of sexual orientation and gender identity (SOGI) data creates barriers for lesbian, gay, bisexual, transgender, and queer (LGBTQ+) people in health care. Barriers to SOGI data collection include physician misperception that patients do not want to answer these questions and discomfort asking SOGI questions. This study aimed to assess patient comfort towards SOGI questions across five quaternary care adult congenital heart disease (ACHD) centres.
Methods:
A survey administered to ACHD patients (≥18 years) asked (1) two-step gender identity and birth sex, (2) acceptance of SOGI data, and (3) the importance for ACHD physicians to know SOGI data. Chi-square tests were used to analyse differences among demographic groups and logistic regression modelled agreement with statement of patient disclosure of SOGI improving patient–physician communication.
Results:
Among 322 ACHD patients, 82% identified as heterosexual and 16% identified as LGBTQ+, across the age ranges 18–29 years (39.4%), 30–49 years (47.8%), 50–64 years (8.7%), and > 65 years (4.0%). Respondents (90.4%) felt comfortable answering SOGI questions. Respondents with bachelor’s/higher education were more likely to “agree” that disclosure of SOGI improves patient–physician communication compared to those with less than bachelor’s education (OR = 2.45; 95% CI 1.41, 4.25; p = .0015).
Conclusion:
These findings suggest that in this largely heterosexual population, SOGI data collection is unlikely to cause patient discomfort. Respondents with higher education were twice as likely to agree that SOGI disclosure improves patient–physician communication. The inclusion of SOGI data in future studies will provide larger samples of underrepresented minorities (e.g. LGBTQ+ population), thereby reducing healthcare disparities within the field of cardiovascular research.
In this textual comparison of seventeenth-century herbals, I show in detail that most of the descriptions and medicinal uses of English herbs included in Culpeper’s small folio The English Physitian (1652) and its enlargement of the following year were lifted straight out of the works of John Parkinson, apothecary. This was a deliberate act by Culpeper, to make available to the people of England the best information on native plant medicines for use in treating their illnesses. He attacked the College of Physicians of London, whom the great majority of the population could not afford to engage, for trying to keep this knowledge secret. Among later historians of the herbal tradition, Culpeper’s work was not accorded the same status as the great English herbals of William Turner, John Gerard, and John Parkinson, not because this borrowing was recognised but because its astrological content worked to divert attention from the quality and source of much of its guidance on treatment. Even contemporaries of Culpeper did not recognise the extent of the borrowing. Comparisons also reveal the limitations of Culpeper’s powers of plant description and his lack of interest in the developing science of botany. The editorial decisions Culpeper made to reduce a great folio herbal to a much smaller book to be sold for 3d touch on domestic and other non-medical uses, while points of discussion common to both authors such as the doctrine of signatures and superstitious beliefs about plants are explored.
Generalised arterial calcification of infancy, an autosomal recessive disorder characterised by abnormal calcification of medium and large-sized arteries, represents a rare cause of dilated cardiomyopathy. We present the case of a two-month-old girl diagnosed posthumously with dilated cardiomyopathy. Studies suggest that early initiation of treatment can improve prognosis in generalised arterial calcification of infancy, so clinicians should be alert to the condition, especially in patients displaying generalised narrowing of medium and large-sized arteries.