Shaping electron wave functions in a carbon nanotube with a parallel magnetic field

A magnetic field, through its vector potential, usually causes measurable changes in the electron wave function only in the direction transverse to the field. Here we demonstrate experimentally and theoretically that in carbon nanotube quantum dots, combining cylindrical topology and bipartite hexagonal lattice, a magnetic field along the nanotube axis impacts also the longitudinal profile of the electronic states. With the high (up to 17T) magnetic fields in our experiment the wave functions can be tuned all the way from "half-wave resonator" shape, with nodes at both ends, to "quarter-wave resonator" shape, with an antinode at one end. This in turn causes a distinct dependence of the conductance on the magnetic field. Our results demonstrate a new strategy for the control of wave functions using magnetic fields in quantum systems with nontrivial lattice and topology.Comment: 5 figure

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Lexical decision in Parkinson's disease: A reply to Brown, McDonald, and Spicer (1999)

Recent semantic priming investigations in Parkinsons disease (PD) employed variants of Neelys (1977) lexical decision paradigm to dissociate the automatic and attentional aspects of semantic activation (McDonald, Brown, Gorell, 1996; Spicer, Brown, Gorell, 1994). In our earlier review, we claimed that the results of Spicer, McDonald and colleagues normal control participants violated the two-process model of information processing (Posner Snyder, 1975) upon which their experimental paradigm had been based (Arnott Chenery, 1999). We argued that, even at the shortest SOA employed, key design modifications to Neelys original experiments biased the tasks employed by Spicer et al. and McDonald et al. towards being assessments of attention-dependent processes. Accordingly, we contended that experimental procedures did not speak to issues of automaticity and, therefore, Spicer, McDonald and colleagues claims of robust automatic semantic activation in PD must be treated with caution

Speech and language screening for school children

Speech and language difficulties are a common reason for referral to child health services during the preschool years. A speech and language problem in the early years may have significant implications for one's communication outcomes in adolescence and adulthood. However, there is considerable variation in what constitutes normal speech and language acquisition. Many preschool children who are late to talk improve spontaneously, while some apparently typical young children may decline in their speech and language performance in later years. The predictive power of an individual's speech-language ability for their later speech-language status improves with age. Speech and language problems at school-entry appear to be a stronger predicator for later communication issues than speech and language problems in the preschool years. With the potential long-term impact of speech and language problems, screening procedures for speech and language problems in school-age children have been developed. This chapter addresses some of the difficulties in implementing population-wide screening for speech and language problems in the early years and reviews some commonly used assessment tools for identifying school children with suspected speech and language problems. Procedures for conducting language screening that are both beneficial to school-age children and cost-effective for society are also discussed

The Autism Diagnostic Observation Schedule and narrative assessment: evidence for specific narrative impairments in autism spectrum disorders

Purpose: The Autism Diagnostic Observation Schedule (ADOS) contains a narrative generation task in which clients tell a story from a wordless picture book; however, the resulting narrative is not usually examined for its linguistic properties. This study aimed to examine narrative generation in autism spectrum disorder (ASD) by comparing narratives elicited from children with ASD during the ADOS to those produced by language-matched typically-developing (TD) peers. Method: Participants were children with ASD (n = 11) and TD controls (n = 17). Both groups were aged 9-15 years and were matched for expressive and receptive language skills and non-verbal intelligence. Narratives were analysed for local structure elements (length, fluency, errors, semantics and syntax), cohesion and global elements (story grammar and internal state language). Result: Results indicated that the narratives of the children with ASD were syntactically less complex, contained more ambiguous pronouns and included fewer story grammar elements than their control counterparts; with further analysis showing differences between younger and older children. Conclusion: The present findings provide evidence that children with ASD exhibit subtle story generation impairments and provide preliminary support for the inclusion of narratives elicited as part of the ADOS in the assessment of specific language skills in this population

Outcomes for School-Aged Children with Aural Atresia

This study compared the language, reading, classroom, and quality of life outcomes of primary school-aged children with aural atresia (AA) to matched controls. Participants included 10 children with AA (eight unilateral) and 10 children with typical hearing matched by chronological and mental age. All children with AA had been fitted with an amplification device. Outcome measures included standardized tests of language, reading, and functional communication questionnaires of children's classroom performance and hearing quality of life. The children with AA recorded significantly reduced hearing quality of life. The two groups did not differ on any other measures. The present preliminary findings suggest that children with AA who receive early amplification have similar language, communication, reading, and classroom outcomes as their typically hearing peers. Despite these promising outcomes, however, the children's quality of life is significantly reduced. Further research is needed to further elucidate these findings

Spelling in children with cochlear implants: evidence of underlying processing differences

This study compared the spelling skills and sub-skills of young children with cochlear implants (CIs) who use spoken language only (n = 14) with those of a same-aged typically hearing (TH) control group (n = 30). Spelling accuracy was assessed using irregular and nonsense word stimuli. Error and regression analyses were conducted to provide insight into the phonological and orthographic spelling strategies used by each group. Results indicated that children with CIs were as accurate as the TH group. However, misspellings made by the CI group were less phonologically plausible, and while nonword spelling accuracy was related to letter-sound knowledge for the TH group, the same relationship was non-significant for the CI group. Hence, despite demonstrating a similar degree of overall spelling success to TH children, children with CIs appeared to apply phonics skills less effectively