Electronic Instability in a Zero-Gap Semiconductor: The Charge-DensityWave in (TaSe4)(2)I

We report a comprehensive study of the paradigmatic quasi-1D compound (TaSe4)(2)I performed by means of angle-resolved photoemission spectroscopy (ARPES) and first-principles electronic structure calculations. We find it to be a zero-gap semiconductor in the nondistorted structure, with non-negligible interchain coupling. Theory and experiment support a Peierls-like scenario for the charge-density wave formation below T-CDW = 263 K, where the incommensurability is a direct consequence of the finite interchain coupling. The formation of small polarons, strongly suggested by the ARPES data, explains the puzzling semiconductor-to-semiconductor transition observed in transport at T-CDW.open114sciescopu

Perceptions of people with mild intellectual disability and their family members about family-based social capital in the Netherlands

Families play an important role in the lives of people with intellectual disability as they do for everyone. However, little research has addressed the views of people with intellectual disability about their families by using self-report. Individual family members may hold different views about their family relationships. Therefore, we used a social capital theoretical perspective to examine (a) how perceptions of people with mild intellectual disability (MID) about their family support networks compare to those of their family members and (b) what factors are associated with any diverging perceptions. Randomly selected participants with MID (n = 111) and their family members (n = 111) were interviewed individually at their homes using the Family Network Method-Intellectual Disability (FNM-ID). The FNM-ID examines how people define their family groups and how they perceive existing supportive relationships within this group. The findings showed that participants with MID perceived that they had somewhat denser family networks (i.e., bonding social capital) than family members perceived them to have and were more likely to report bridging social capital. They reported more relationships that involved them providing support to family members. This difference in estimation was greater when the participant with MID displayed higher levels of externalizing behaviour problems. They also perceived more reciprocity in their relationships with family. No differences were found in the estimated numbers of significant family members and relationships in which support was received. It is concluded that people with MID and their family members have different perceptions on several aspects of the family support network. Family professionals and services should seek the views of people with intellectual disability and their family members when carrying out assessments or organizing supports. [Abstract copyright: © 2021 The Authors. Health and Social Care in the Community published by John Wiley & Sons Ltd.

Social capital and the reciprocal nature of family relationships : the perspective of individuals with mild intellectual disability

Even though family plays a significant role in the lives of individuals with intellectual disability, little research has included their own views about their families. This study examined how 138 people with mild intellectual disability describe their family group, with a focus on the reciprocal nature of the emotional support in relationships with family members. Participants reported “significant” family members beyond the nuclear family, and parents were seen as the main provider of support. Only half of participants had a support relationship with siblings and just 13% of participants reported partners. About 30% of support was reciprocal, and reciprocity varied greatly with the types of family connection (e.g., siblings, peers). Implications for future research as well as practice are discussed

Parallel preconditioners and high order elements for microwave imaging

This paper combines the use of high order finite element methods with parallel preconditioners of domain decomposition type for solving electromagnetic problems arising from brain microwave imaging. The numerical algorithms involved in such complex imaging systems are computationally expensive since they require solving the direct problem of Maxwell's equations several times. Moreover, wave propagation problems in the high frequency regime are challenging because a sufficiently high number of unknowns is required to accurately represent the solution. In order to use these algorithms in practice for brain stroke diagnosis, running time should be reasonable. The method presented in this paper, coupling high order finite elements and parallel preconditioners, makes it possible to reduce the overall computational cost and simulation time while maintaining accuracy

Two-level DDM preconditioners for positive Maxwell equations

In this paper we develop and analyse domain decomposition methods for linear systems of equations arising from conforming finite element discretisations of positive Maxwell-type equations. Convergence of domain decomposition methods rely heavily on the efficiency of the coarse space used in the second level. We design adaptive coarse spaces that complement the near-kernel space made of the gradient of scalar functions. This extends the results in [2] to the variable coefficient case and non-convex domains at the expense of a larger coarse space

Shielding efficiency and E(J) characteristics measured on large melt cast Bi-2212 hollow cylinders in axial magnetic fields

We show that tubes of melt cast Bi-2212 used as current leads for LTS magnets can also act as efficient magnetic shields. The magnetic screening properties under an axial DC magnetic field are characterized at several temperatures below the liquid nitrogen temperature (77 K). Two main shielding properties are studied and compared with those of Bi-2223, a material that has been considered in the past for bulk magnetic shields. The first property is related to the maximum magnetic flux density that can be screened, Blim; it is defined as the applied magnetic flux density below which the field attenuation measured at the centre of the shield exceeds 1000. For a cylinder of Bi-2212 with a wall thickness of 5 mm and a large ratio of length over radius, Blim is evaluated to 1 T at T = 10 K. This value largely exceeds the Blim value measured at the same temperature on similar tubes of Bi-2223. The second shielding property that is characterized is the dependence of Blim with respect to variations of the sweep rate of the applied field, dBapp/dt. This dependence is interpreted in terms of the power law E = Ec(J/Jc)^n and allows us to determine the exponent n of this E(J) characteristics for Bi-2212. The characterization of the magnetic field relaxation involves very small values of the electric field. This gives us the opportunity to experimentally determine the E(J) law in an unexplored region of small electric fields. Combining these results with transport and AC shielding measurements, we construct a piecewise E(J) law that spans over 8 orders of magnitude of the electric field.Comment: 16 pages, 7 figure

To buy or not to buy-evaluating commercial AI solutions in radiology (the ECLAIR guidelines).

Artificial intelligence (AI) has made impressive progress over the past few years, including many applications in medical imaging. Numerous commercial solutions based on AI techniques are now available for sale, forcing radiology practices to learn how to properly assess these tools. While several guidelines describing good practices for conducting and reporting AI-based research in medicine and radiology have been published, fewer efforts have focused on recommendations addressing the key questions to consider when critically assessing AI solutions before purchase. Commercial AI solutions are typically complicated software products, for the evaluation of which many factors are to be considered. In this work, authors from academia and industry have joined efforts to propose a practical framework that will help stakeholders evaluate commercial AI solutions in radiology (the ECLAIR guidelines) and reach an informed decision. Topics to consider in the evaluation include the relevance of the solution from the point of view of each stakeholder, issues regarding performance and validation, usability and integration, regulatory and legal aspects, and financial and support services. KEY POINTS: • Numerous commercial solutions based on artificial intelligence techniques are now available for sale, and radiology practices have to learn how to properly assess these tools. • We propose a framework focusing on practical points to consider when assessing an AI solution in medical imaging, allowing all stakeholders to conduct relevant discussions with manufacturers and reach an informed decision as to whether to purchase an AI commercial solution for imaging applications. • Topics to consider in the evaluation include the relevance of the solution from the point of view of each stakeholder, issues regarding performance and validation, usability and integration, regulatory and legal aspects, and financial and support services

'Connectedness' between people with intellectual disabilities and challenging behaviour and support staff : perceptions of psychologists and support staff

The tacit practical knowledge of psychologists and support staff to foster a real connection between support staff and people with intellectual disabilities and challenging behaviour was explored. Therefore, six dyads comprising individuals with intellectual disabilities and challenging behaviour and their support staff were video recorded during joint engagement in an activity. To tap into the implicit knowledge of professionals about when staff have ‘a real connection’ with a person with an intellectual disability, 10 psychologists and 10 support staff were asked to pinpoint these moments in the pre-recorded video compilation. They also shared their interpretations about what they considered to be a real connection. The results displayed that participants designated real connections as occurring when they noticed concrete interactions taking place. Based on thematic analysis of the data, four themes were identified that encapsulated what professionals deemed to be a real connection. In conclusion: joint engagement in an activity appears to be a context that fosters opportunities for real connection. Furthermore, support staff should adopt a sensitive attitude and create a safe atmosphere, to establish real connections