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Spatial reasoning, recognised as playing a critical role across STEM disciplines, is gaining prominence in mathematics education, not only as fundamental to mathematics, but also as embodied mathem...

A 25- year old male patient, with subcarinal mass projecting into carina and lower tracheal lumen underwent carinal resection and reconstruction surgery. This was done through the laryngeal drop and bilateral thoracotomy approach. Intraoperative course was complicated by persistent hypoxia and arrhythmias. This report explores the various anaesthetic issues involved which were effectively managed. Keywords: Arrythmias, Carinal resection, Cross field ventilation, Intermittent apnea technique.

The characteristics of cross-field pitting among compression wood, lateral wood, and opposite wood, in the stem woods ofGinkgo bilobaandPinus densiflorawere investigated with optical and scanning electron microscopy. InGinkgo biloba, compression wood exhibited piceoid pits, while lateral and opposite wood exhibited cupressoid pits. The compression wood ofPinus densifloraexhibited cupressoid pits and piceoid pits, while lateral wood and opposite wood exhibited pinoid and window-like pits in the cross-field. In both species, compression wood yielded the smallest pit number among each part, while opposite wood yielded the greatest pit number per cross-field. Cross-field pitting diameters of compression wood and opposite wood were significantly smaller than lateral wood inGinkgo biloba, while the cross-field pitting of compression wood was the smallest inPinus densiflora. Radial tracheid diameter of compression wood was slightly smaller than lateral and opposite wood inGinkgo bilobaand significantly smaller than lateral and opposite wood inPinus densiflora. In conclusion, the cross-field pitting type, pit number, and cross-field pitting diameter could be used to identify reaction wood in the stem wood ofGinkgo bilobaandPinus densiflora.

This study is conducted to develop a collaborative visualization framework in the cross-field working group. The ultimate goal of this project is to provide a proper framework that can be used to develop a platform to allow collaborative visualization to be implemented inter-disciplinary groups, in two different settings perspectives; amateurs and professionals. The project begins with preliminary works to define the collaborative visualization based on previous researches. This project will also focus on the factors to develop an effective collaborative working environment thru visualization and shared understanding among the staffs/users from inter-disciplinary backgrounds. In addition, this project will also look into the interaction between human cognition and ICT attributes of visualization in developing an efficient working group to achieve a common goals and objectives. Towards the end of the project, the framework will be tested to validate its possible contributions to the targeted collaborative working groups.

Purpose Medical humanities is a field which implies collaborative work across disciplines although the degree to which this actually occurs is unknown. Our purpose was to determine the degree of joint work in medical humanities through analysis of authorship and acknowledgements in the two main medical humanities journals. Methods Observational survey of authorship. We studied authorship data in all papers published in the two major general medical humanities journals between 2009 and 2018 (n=595). Results Two-thirds of papers (67.4%) had single authors, of whom a majority declared a single disciplinary affiliation (70.3%). The titles of 60.8% of papers explicitly suggested collaborative content of which 19.9% had multiple authors from more than one discipline (not within the same school); of the remainder, almost half (48.1%) had a single, single-disciplinary author (although 8.5% demonstrated interdisciplinarity in the acknowledgements). One-third of papers (193/595;33%) referenced one or more people in the acknowledgements. Among papers whose titles suggested humanities or medical content only, authorship lists of 10.2% and 17.9% respectively demonstrated collaborative scholarship. Conclusions Despite considerable involvement from both humanities and medical practitioners, there is still substantial scope for enhanced emphasis on collaborative (multi-, inter- and trans-disciplinary) seminars and exchanges in the medical humanities and editorial policies to promote transparency of the nature of collaborative work among disciplines. Journal editors and editorial boards should reflect on the opportunity to promote enhanced visibility of joint work in scholarship in the medical humanities through reflection and review of current editorial policies.

The 2021 International Symposium on Physical Design lifetime achievement award goes to Dr. Louis K. Scheffer for his outstand contributions to the field. This autobiography in Lou's own words provides a glimpse of what has happened through his career.

Since the outbreak of COVID-19, in addition to the continuous increment in the number of infected patients, the number of COVID-19-related papers has also increased significantly. According to the statistics, its number even exceeds the research of some research fields over many years. Similar to COVID-19, the related research on COVID-19 also seems highly infectious. What causes this situation? By crawling the data of COVID-19-related papers from web of Sciences this year, we found that there are three mechanisms to promote the rapid growth of the number of COVID-19 papers: incentive mechanism, cross-field collaboration mechanism, and potential impact mechanism of writing papers. To understand the impact of COVID-19 on cross-domain paper network further, we proposed a new construction method of multi-field paper association structure network based on COVID-19. The paper association mechanism and the wall breaking principle between multiple research fields were found through the experiments. Then, combined with the constructed network, we gave the knowledge dissemination model of the new discoveries in multiple fields and obtained some relevant new findings.

Energetic particle fluxes in the outer magnetosphere present a significant challenge to modelling efforts as they can vary by orders of magnitude in response to solar wind driving conditions. In this article, we demonstrate the ability to propagate test particles through global MHD simulations to a high level of precision and use this to map the cross-field radial transport associated with relativistic electrons undergoing drift orbit bifurcations (DOBs). The simulations predict DOBs primarily occur within an Earth radius of the magnetopause loss cone and appears significantly different for southward and northward interplanetary magnetic field orientations. The changes to the second invariant are shown to manifest as a dropout in particle fluxes with pitch angles close to 90$^\circ$ and indicate DOBs are a cause of butterfly pitch angle distributions within the night-time sector. The convective electric field, not included in previous DOB studies, is found to have a significant effect on the resultant long term transport, and losses to the magnetopause and atmosphere are identified as a potential method for incorporating DOBs within Fokker-Planck transport models., 12 pages, 8 figures. Accepted for publication as a Journal of Geophysical Research article on 04 September 2021

Interstitial spaces are informal settings where interactions among actors from different organizational fields are more likely to succeed despite the institutional complexity that they face. Individuals acting as “catalysts” have been identified as being particularly important in the dynamics of these interstitial spaces. However, the focus to date has been on individuals interacting in interstitial spaces that have developed informally, and we know little about how formal organizations might purposefully create and manage interstitial spaces to initiate cross-field interaction. Using data from a study of six organizations involved in technology transfer activities between universities and industry in Italy, we explore how formal organizations use interstitial spaces to encourage cross-field collaboration and identify the set of formal and informal activities employed by catalysts to manage the complexity that arises. In addition, our analysis identifies two activities implemented at the organizational and field level by the formal organizations to support the interstitial spaces. Based on these results, we develop a model of the management of interstitial spaces by formal organizations.

This chapter evaluates the implications of recent crises for solidarity organisations in France. The main aim is to assess whether solidarity remains nationally bounded or otherwise follows some consistent pattern of transnationalisation. By focusing on the fields of migration, unemployment and disability, the chapter examines the main attributes of solidarity organisations; in particular, the analysis aims to evaluate how transnational features relate to endogenous characteristics, such as activities, roles and networks affecting their particular experiences within changing fields of solidarity. Crucially, findings show that the economic crisis and welfare retrenchment in France have well served the purpose of governments willing to pre-empt strong political challenge by potential solidarity movements.

Superconducting stacks and bulks can act as very strong magnets (more than 17 T), but they lose their magnetization in the presence of alternating (or ripple) transverse magnetic fields, due to the dynamic magneto-resistance. This demagnetization is a major concern for applications requiring high run times, such as motors and generators, where ripple fields are of high amplitude and frequency. We have developed a numerical model based on dynamic magneto-resistance that is much faster than the conventional Power-Law-resistivity model, enabling us to simulate high number of cycles with the same accuracy. We simulate demagnetization behavior of superconducting stacks made of 10-100 tapes for up to 2 million cycles of applied ripple field. We found that for high number of cycles, the trapped field reaches non-zero stationary values for both superconducting bulks and stacks; as long as the ripple field amplitudes are below the parallel penetration field, being determined by the penetration field for a single tape in stacks. Bulks keep substantial stationary values for much higher ripple field amplitudes than the stacks, being relevant for high number of cycles. However, for low number of cycles, stacks lose much less magnetization as compared to bulks., 21 pages, 9 figures

So-called “anomalous” plasma transport due to micro- and meso-scale fluctuations of electromagnetic fields caused by different plasma instabilities is one of the backbones of plasma physics in magnetic fusion devices. In this chapter the main mechanisms driving and stabilizing the most typical edge plasma instabilities are considered and the underlying physics is discussed.

We present a new fully automatic block-decomposition algorithm for feature-preserving, strongly hex-dominant meshing, that yields results with a drastically larger percentage of hex elements than prior art. Our method is guided by a surface field that conforms to both surface curvature and feature lines, and exploits an ordered set of cutting loops that evenly cover the input surface, defining an arrangement of loops suitable for hex-element generation. We decompose the solid into coarse blocks by iteratively cutting it with surfaces bounded by these loops. The vast majority of the obtained blocks can be turned into hexahedral cells via simple midpoint subdivision. Our method produces pure hexahedral meshes in approximately 80% of the cases, and hex-dominant meshes with less than 2% non-hexahedral cells in the remaining cases. We demonstrate the robustness of our method on 70+ models, including CAD objects with features of various complexity, organic and synthetic shapes, and provide extensive comparisons to prior art, demonstrating its superiority.

A theoretical model of feedback instability is proposed to explain the mechanism of correlation between the detachment and the cross-field plasma transport. It is shown that the feedback instability on the detached divertor plasma can be induced in a certain condition in which the volume recombination frequency is larger than the ion cyclotron frequency in the recombination region. Further, the density gradient and the electric field in the direction perpendicular to the magnetic flux surface are not zero in the condition. The feedback instability can provide the cross-field plasma transport in the boundary layer of magnetic fusion torus devices. Furthermore, the properties of the radial transport observed in the NAGDIS-II linear device experiment are compared with the estimation by the feedback instability model. The dependence of the feedback instability mode on the total collision frequency and the recombination coefficient and the density gradient has been also investigated. Although the dependency on the total collision frequency and the recombination coefficient for the typical fusion torus device case is opposite to that for the NAGDIS-II case, the represented dependencies show the reasonable tendency in each case.

A new permineralized stem, Protophyllocladoxylon yiwuense Gou et Feng sp. nov., is described from the Middle Jurassic Xishanyao Formation in Naomaohu Town of Yiwu County, Hami City, Xinjiang Uygur Autonomous Region, Northwest China. The stem is only preserved with secondary xylem, which is pycnoxylic and exclusively composed of tracheids and parenchymatous rays. The tracheids have uniseriate or biseriate, alternately arranged bordered pits on their radial walls, and uniseriate bordered pits on the tangential walls. The rays are uniseriate or partially biseriate, up to 34 cells high. There are one or two large, simple pits in each cross field. A branch trace horizontally passes through the secondary xylem showing anatomical structures identical to the secondary xylem. Analyses of the growth-ring width and mean sensitivity values indicate that P. yiwuense had long growing seasons with readily available water supplies and favorable paleoclimatic conditions. White-rot decay features are commonly recognized in the stem, including pocket-like cavities, complete removal of the middle lamellae, thickened corners and separation of the secondary walls of tracheids, as well as septa-like structures in the tracheid lumens due to the cell's reactions to fungal activity. Our study sheds new light into the plant diversity and paleoenvironmental and paleoecological conditions of the Middle Jurassic.

In this paper, the physical model of low voltage Direct-current (DC) glow discharge in cross field is established. Based on the magneto-hydrodynamic method (MHD), the mathematical expression of steady-state plasma physical parameters under cross field condition is derived, and the influence of magnetic field on low-pressure glow plasma physical parameters is analyzed. The theoretical results show that the magnetic field can effectively increase the electron density and ion density of plasma at low pressure. The magnetic field can increase the glow discharge current, and the introduction of the magnetic field makes the plasma concentrate to the discharge center. The effects of parallel field and cross field on glow discharge are compared by experiments. The experimental results show that the cross field has more influence on the glow plasma density than the parallel field, and the experimental results are consistent with the theoretical results.

Magnetic field sensors based on anisotropic magnetoresistance (AMR) are widely used in many scientific and industrial applications. The AMR sensor sensitivity is superior to Hall probes and size and power consumption is superior to fluxgates. However, the noise properties and the temperature stability of AMR sensors are typically worse than for fluxgates. These properties define the typical applications—less precise vectorial or gradient measurements of the magnetic field within less than ±1 mT range. AMR sensors are typically calibrated for sensitivity, offset, and orthogonality errors. However, there is another important source of error—sensitivity to the magnetic field applied in the perpendicular direction to the measurement axis. This so-called cross-field error is inherent to AMR sensors and can influence the measurements significantly. Flipping (set/reset pulses) and closed-loop operation of the sensor can reduce the cross-field error. In this paper, we present a novel approach using full vectorial compensation of the measured magnetic field resulting in a complete elimination of the cross-field effect. The vectorial compensation provided superior results over alternative approaches that were also evaluated.

The exponential increase in the number of scientific publications raises the question of whether the sciences are expanding into a fractured structure, making cross-field communication difficult. On the other hand, scientists may be motivated to learn extensively across fields to enhance their innovative capacity, and this may offset the negative effects of fragmentation. Through an investigation of the distances within and clustering of cross-sectional citation networks, this study presents evidence that fields of science become more integrated over time. The average citation distance between papers published in the same year decreased from approximately 5.33 to 3.18 steps between 1950 and 2018. This observation is attributed to the growth of cross-field communication throughout the entire period as well as the growing importance of high impact papers to bridge networks in the same year. Three empirical findings support this conclusion. First, distances decreased between almost all disciplines throughout the time period. Second, inequality in the number of citations received by papers increased, and as a consequence the shortest paths in the network depend more on high impact papers later in the period. Third, the dispersion of connections between fields increased continually. Moreover, these changes did not entail a lower level of clustering of citations. Both within- and cross-field citations show a similar rate of slowly growing clustering values in all years. The latter findings suggest that domain spanning scholarly communication is partly enabled by new fields that connect disciplines.

We describe an adaptive version of a method for generating valid naturally curved quadrilateral meshes. The method uses a guiding field, derived from the concept of a cross field, to create block decompositions of multiply connected two dimensional domains. The a priori curved quadrilateral blocks can be further split into a finer high-order mesh as needed. The guiding field is computed by a Laplace equation solver using a continuous Galerkin or discontinuous Galerkin spectral element formulation. This operation is aided by using $p$-adaptation to achieve faster convergence of the solution with respect to the computational cost. From the guiding field, irregular nodes and separatrices can be accurately located. A first version of the code is implemented in the open source spectral element framework Nektar++ and its dedicated high order mesh generation platform NekMesh., Comment: 13 pages, 14 figures, accepted for publication in the Proceedings of 28th International Meshing Roundtable

We describe a high order technique to generate quadrilateral decompositions and meshes for complex two dimensional domains using spectral elements in a field guided procedure. Inspired by cross field methods, we never actually compute crosses. Instead, we compute a high order accurate guiding field using a continuous Galerkin (CG) or discontinuous Galerkin (DG) spectral element method to solve a Laplace equation for each of the field variables using the open source code Nektar++. The spectral method provides spectral convergence and sub-element resolution of the fields. The DG approximation allows meshing of corners that are not multiples of $\pi/2$ in a discretization consistent manner, when needed. The high order field can then be exploited to accurately find irregular nodes, and can be accurately integrated using a high order separatrix integration method to avoid features like limit cycles. The result is a mesh with naturally curved quadrilateral elements that do not need to be curved a posteriori to eliminate invalid elements. The mesh generation procedure is implemented in the open source mesh generation program NekMesh., Comment: 31 pages, 21 figures, accepted for publication in Journal of Computational Physics

PurposeThis paper aims to explore how an academic graduate from the cross field between the humanities and the social sciences and blue-collar workers learns to scaffold knowing in a small- to medium-sized enterprise (SME).Design/methodology/approachA case study was conducted in an SME that employed the first academic graduate among the company’s blue-collar workers. The paper applies a practice-oriented theoretical framework to study scaffolding knowing among the workers.FindingsAn academic graduate does not necessarily apply subject-specific knowledge from his or her university education in the SME practice. Rather, general academic knowing and academic work practice is applied when scaffolding knowing in the SME. Further, this depends not only on the knowing of the academic graduate but also on his/her ability to apply knowing and the willingness to change in practice.Research limitations/implicationsThe study is a single case study gaining in-depth insights into one particular case. This calls for more research.Practical implicationsThe study points at the importance for managers and academic graduates in SMEs to foster learning activities and to be aware of and develop ways to integrate the general academic knowing.Originality/valueThe case study provides new insights into the concept of scaffolding knowing in practice theory. Further, it gains unique insights into the practical possibility of employing graduates from higher education in SMEs.

International audience; The subject matter of this paper concerns the Vlasov-Poisson equations in the framework of magnetic confinement. We study the behavior of the Vlasov-Poisson system with strong external magnetic field, when neglecting the curvature of the magnetic lines. The arguments rely on averaging techniques. We intend to determine second order approximations and to retrieve the usual electric cross field drift, the magnetic gradient drift, etc.

Building on the case of social impact investing in the UK, this chapter develops a mechanism for the emergence of cooperative ties between financial and nonfinancial actors that is key to financialization processes. Golka draws on pragmatist scholarship to develop the notion of a “resonance mechanism” to better understand how strategic actors succeed in motivating others to cooperate. He finds that cooperation is likely to emerge when strategic narratives are aligned with “resonance spaces”—situations that render these narratives acceptable to positioned actors. Linking the concept with current research on financialization, Golka shows how such a perspective helps to understand trajectories of financialization as well as their absence.

A model calculation is presented to characterize the anomalous cross-field transport of electrons in a Hall thruster geometry. The anomalous nature of the transport is attributed to the chaotic dynamics of the electrons arising from their interaction with fluctuating unstable electrostatic fields of the electron cyclotron drift instability that is endemic in these devices. Electrons gain energy from these background waves leading to a significant increase in their temperature along the perpendicular direction $T_\perp / T_\parallel \sim 4$ and an enhanced cross-field electron transport along the thruster axial direction. It is shown that the wave-particle interaction induces a mean velocity of the electrons along the axial direction, which is of the same order of magnitude as seen in experimental observations., Comment: arXiv admin note: substantial text overlap with arXiv:1907.08407

Transition-metal-catalyzed C–H activation represents one of most attractive research fields in modern organic chemistry while theoretical studies have become a popular and effective tool for elucidating mechanism nowadays. The recent achievements in the cross field of the two orientations are reviewed in this article. The first part introduced the advances in theoretical study on transition-metal-catalyzed C–H activation. The elegant work reported mainly in and after 2013, classified according to the mechanisms of C–H activation, were covered. The second part provided an analysis on the distribution of quantum-chemical methods, solvation models and basis sets in the collected theoretical studies.

Mapping the evolution of scientific fields has drawn much attention in recent years. Researchers have proposed various methods to describe, explain and predict different aspects of science. Network-based analysis has been widely used for knowledge networks, in order to track the changes of research topics and the spread of scientific ideas. Here we propose a novel approach for mapping the science from the perspective of cross-field authors. Computer science is selected based on its interdisciplinary applications. We build a scientific network consisting of computer science conferences as nodes, and two conferences are linked if there exist authors that published papers on both conferences. The scientific fields are identified by community detection algorithm. The results suggest the proposed method based on author overlaps across fields are effective in mapping the science.

We present a new 3D magnetohydrostatic (MHS) direct elliptic solver for extrapolating the coronal magnetic field from photospheric boundary conditions in a manner consistent with an assumed plasma distribution. We use it to study the uniqueness of the reconstructed magnetic field as a function of how significant the plasma forcing is on the force balance of the magnetic field. To this end, we consider an analytic MHS model as ground truth. The model uses two free parameters to decompose the current into two parts: a magnetic-field-aligned component and a cross-field component. We perform a comprehensive study of the 2D parameter space to understand under what conditions the ground truth can be reproduced uniquely. We find that current oriented perpendicular to the magnetic field has a smaller solution space than the same amount of current oriented parallel to the magnetic field, and so MHS regimes with larger proportions of plasma-related forcing may be a promising avenue toward finding unique magnetic field reconstructions.