Auditory perceptual learning in autistic adults

The automatic retuning of phoneme categories to better adapt to the speech of a novel talker has been extensively documented across various (neurotypical) populations, including both adults and children. However, no studies have examined auditory perceptual learning effects in populations atypical in perceptual, social, and language processing for communication, such as populations with autism. Employing a classic lexically-guided perceptual learning paradigm, the present study investigated perceptual learning effects in Australian English autistic and non-autistic adults. The findings revealed that automatic attunement to existing phoneme categories was not activated in the autistic group in the same manner as for non-autistic control subjects. Specifically, autistic adults were able to both successfully discern lexical items and to categorize speech sounds; however, they did not show effects of perceptual retuning to talkers. These findings may have implications for the application of current sensory theories (e.g., Bayesian decision theory) to speech and language processing by autistic individuals. Lay Summary Lexically guided perceptual learning assists in the disambiguation of speech from a novel talker. The present study established that while Australian English autistic adult listeners were able to successfully discern lexical items and categorize speech sounds in their native language, perceptual flexibility in updating speaker-specific phonemic knowledge when exposed to a novel talker was not available. Implications for speech and language processing by autistic individuals as well as current sensory theories are discussed

Helicobacter pylori and respiratory diseases: 2021 update

Helicobacter pylori (H. pylori) is a Gram-negative bacterium involved in the development of gastritis, peptic ulcer disease, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue. Unexplained iron deficiency anemia, idiopathic thrombocytopenic purpura and vitamin B12 deficiency have also been related to H. pylori infection, whereas for other extra-gastric diseases, the debate is still open. In this review, we evaluate and discuss the potential involvement of H. pylori infection in the pathogenesis of several respiratory diseases. A MEDLINE search of all studies published in English from 1965 to 2021 was carried out. Controversial findings have been reported in patients with bronchial asthma, chronic obstructive pulmonary disease, bronchiectasis, lung cancer, tuberculosis, cystic fibrosis, and sarcoidosis. Most of the available literature is concerned with case-control studies based on seroprevalence, with a small sample size and low consideration of confounders, which represents a potential issue. So far, there is no clear evidence of a causal association between H. pylori infection and respiratory diseases, and larger studies with appropriate epidemiological design are required

Supporting children with severe to profound learning difficulties and complex communication needs to make their views known: observation tools and methods

All children have the right to shape decisions that influence their lives. Yet, children with severe-to-profound intellectual disabilities and complex communication needs are often marginalized from this process. Here, we examined the utility of a set of tools incorporating ethnographic and structured observational methods with three such children. We specifically examined the communicative behavior that these children used to share their views and the ways in which adults recognized and responded to them. The three case studies illustrate (1) that these children have ways to make their intentions known, even though they may use idiosyncratic ways of doing so; (2) that adults play important roles in supporting their communicative bids; and (3) that this set of tools was sufficiently sensitive to subtle and fine-grained nonverbal cues that might otherwise be overlooked

Research methods for children with multiple needs: developing techniques to facilitate all children and young people to have 'a voice'

AIM: This study aimed to investigate the experiences of children and young people being educated in residential special schools, with a particular focus on how their rights and wellbeing were being promoted by their schools. METHOD: The study was conducted using participatory research principles and aimed to develop techniques and approaches that would support the inclusion of all children. FINDINGS: The findings indicated that the techniques developed during this study helped to provide insight into the experiences of pupils with a wide range of special needs, and facilitated their voices. The piloting of a method that integrated ethnographic observation techniques with checklists adopted from the SCERTS framework (developed by Prizant and colleagues) provided important insights into the experiences and preferences of children with the greatest learning and communication needs, and is an approach worthy of further development. LIMITATIONS: The study was conducted over a very short time frame, one academic term, which influenced the time available to refine techniques and work with our young researchers’ group. Whilst every residential special school in England was invited to participate, the sample was based on those schools that volunteered, many with good and outstanding Ofsted ratings. Therefore, the sample may not be fully representative of the range of experiences provided by residential special schools in England. CONCLUSION: The development of specific techniques to facilitate an understanding of the views and experiences of children who experience significant challenges in communication is possible. The knowledge, skills and expertise of educational psychologists and other professionals can be harnessed to respond creatively to this challenge and it is important to acknowledge the reciprocal value of professional practice and research skills

"The dots just don't join up": understanding the support needs of families of children on the autism spectrum

Much research has documented the elevated levels of stress experienced by families of autistic children. Yet remarkably little research has examined the types of support that these families perceive to be beneficial to their lives. This study, co-produced by researchers and school-based professionals, sought to establish these families’ support needs from their own perspectives. In total, 139 parents of autistic children with additional intellectual disabilities and limited spoken communication, all attending an inner-city London school, participated in an initial survey examining parental wellbeing, self-efficacy and the extent to which they felt supported. Semi-structured interviews were conducted with a subgroup of parents (n = 17), some of whom reported in the survey that they felt unsupported, in order to gain their in-depth perspectives. The results from both the survey and the interviews suggested that existing support (particularly from formal support services) was not meeting parents’ needs, which ultimately made them feel isolated and alienated. Parents who were interviewed called for service provision that adopted a relational, family-centred approach – one that understands the specific needs of the whole family, builds a close working relationship with them and ensures that they are supported at times when the parents and families feel they need it most

Energy localization in carbon nanotubes

In this paper, the energy localization phenomena in low-frequency nonlinear oscillations of single-walled carbon nanotubes (SWNTs) are analysed. The SWNTs dynamics is studied in the framework of the Sanders-Koiter shell theory. Simply supported and free boundary conditions are considered. The effect of the aspect ratio on the analytical and numerical values of the localization threshold is investigated in nonlinear field

Eigenfrequencies and vibration modes of carbon nanotubes

In 1991 Iijima discovered Carbon Nanotubes, he synthesised molecular carbon structures in the form of fullerenes and then reported the preparation of a new type of finite carbon structure consisting of needle-like tubes, the carbon nanotubes, described as helical microtubules of graphitic carbon. Examples of applications of Carbon Nanotubes (CNTs) can be found in ultrahigh frequency nanomechanical resonators, in a large number of nanoelectromechanical devices such as sensors, oscillators, charge detectors and field emission devices. The reduction of the size and the increment of the stiffness of a resonator magnify its resonant frequencies and reduce its energy consumption, improving its sensitivity. The modal analysis of carbon nanotubes is important because it allows to obtain the resonant frequencies and mode shapes, which influence the mechanical and electronic properties of the nanotube resonators. A large number of experiments and atomistic simulations were conducted both on single-walled (SWNTs) and multi-walled carbon nanotubes (MWNTs). The present work is concerned with the analysis of low-frequency linear vibrations of SWNTs: two approaches are presented: a fully analytical method based on a simplified theory and a semi-analytical method based on the theory of thin walled shells. The semi-analytical approach (shortly called “numerical approach”) is based on the Sanders-Koiter shell theory and the Rayleigh-Ritz numerical procedure. The nanotube deformation is described in terms of longitudinal, circumferential and radial displacement fields, which are expanded by means of a double mixed series based on Chebyshev polynomials for the longitudinal variable and harmonic functions for the circumferential variable. The Rayleigh-Ritz method is then applied to obtain numerically approximate natural frequencies and mode shapes. The second approach is based on a reduced version of the Sanders-Koiter shell theory, obtained by assuming small ring and tangential shear deformations. These assumptions allow to condense both the longitudinal and the circumferential displacement fields. A fourth-order partial differential equation for the radial displacement field is derived. Eigenfunctions are formally obtained analytically, then the numerical solution of the dispersion equation gives the natural frequencies and the corresponding normal modes. The methods are fully validated by comparing the natural frequencies of the SWNTs with data available in literature, namely: experiments, molecular dynamics simulations and finite element analyses. A comparison between the results of the numerical and analytical approach is carried out in order to check the accuracy of the last one. It is worthwhile to stress that the analytical model allows to obtain results with very low computational effort. On the other hand the numerical approach is able to handle the most realistic boundary conditions of SWNTs (free-free, clamped-free) with extreme accuracy. Both methods are suitable for a forthcoming extension to multi-walled nanotubes and nonlinear vibrations

Nonlinear vibrations and energy distribution of carbon nanotubes

The nonlinear vibrations of Single-Walled Carbon Nanotubes are analysed. The Sanders-Koiter elastic shell theory is applied in order to obtain the elastic strain energy and kinetic energy. The carbon nanotube deformation is described in terms of longitudinal, circumferential and radial displacement fields. The theory considers geometric nonlinearities due to large amplitude of vibration. The displacement fields are expanded by means of a double series based on harmonic functions for the circumferential variable and Chebyshev polynomials for the longitudinal variable. The Rayleigh-Ritz method is applied to obtain approximate natural frequencies and mode shapes. Free boundary conditions are considered. In the nonlinear analysis, the three displacement fields are re-expanded by using approximate eigenfunctions. An energy approach based on the Lagrange equations is considered in order to obtain a set of nonlinear ordinary differential equations. The total energy distribution of the shell is studied by considering combinations of different vibration modes. The effect of the conjugate modes participation is analysed