Acoustic-phonetic perception refers to the ability to perceive and discriminate between speech sounds. Acquired impairment of acoustic-phonetic perception is known historically as "pure word deafness" and typically follows bilateral lesions of the cortical auditory system. The extent to which this deficit occurs after unilateral left hemisphere damage and the critical left hemisphere areas involved are not well defined.
View Article and Find Full Text PDFPeople with aphasia often show partial impairments on a given task. This trial-to-trial variability offers a potential window into understanding how damaged language networks function. We test the hypothesis that successful word reading in participants with phonological system damage reflects semantic system recruitment.
View Article and Find Full Text PDFMagnesium borohydride (Mg(BH)) is a promising material for solid state hydrogen storage. However, the predicted reversible hydrogen sorption properties at moderate temperatures have not been reached due to sluggish hydrogen sorption kinetics. Hydrogen (H) → deuterium (D) exchange experiments can contribute to the understanding of the stability of the BH anion.
View Article and Find Full Text PDFUnderstanding the neural basis of recovery from stroke is a major research goal. Many functional neuroimaging studies have identified changes in brain activity in people with aphasia, but it is unclear whether these changes truly support successful performance or merely reflect increased task difficulty. We addressed this problem by examining differences in brain activity associated with correct and incorrect responses on an overt reading task.
View Article and Find Full Text PDFObjective: Voxel-based lesion-symptom mapping (VLSM) was used to localize impairments specific to multiword (phrase and sentence) spoken language comprehension.
Methods: Participants were 51 right-handed patients with chronic left hemisphere stroke. They performed an auditory description naming (ADN) task requiring comprehension of a verbal description, an auditory sentence comprehension (ASC) task, and a picture naming (PN) task.
ACS Appl Mater Interfaces
January 2017
Self-supported fcc Pd-Cu-M (M = Y, Ti, Zr, V, Nb, and Ni) alloys were studied as potential hydrogen purification membranes. The effects of small additions (1-2.6 at.
View Article and Find Full Text PDFPatients with surface dyslexia have disproportionate difficulty pronouncing irregularly spelled words (e.g. pint), suggesting impaired use of lexical-semantic information to mediate phonological retrieval.
View Article and Find Full Text PDFReversible hydrogen storage under ambient conditions has been identified as a major bottleneck in enabling a future hydrogen economy. Herein, we report an amorphous vanadium(III) alkyl hydride gel that binds hydrogen through the Kubas interaction. The material possesses a gravimetric adsorption capacity of 5.
View Article and Find Full Text PDFChem Commun (Camb)
November 2015
The effects of the addition of small amount of Zr (less than 2 at%) to the fcc phase of the Pd-Cu hydrogen separation alloy were investigated. Hydrogen flux variations in Pd-Cu and Pd-Cu-Zr alloys in the presence of 1000 ppm H2S + H2 feed gas showed a marked effect of Zr addition in improving the resistance to sulphur poisoning.
View Article and Find Full Text PDFAlthough anti-predator behavior systems have been studied in diverse taxa, less is known about how prey species detect and assess the immediate threat posed by a predator based on its behavior. In this study, we evaluated a potential cue that some species may utilize when assessing predation threat-the predator's body and head orientation. We tested the effect of this orientation cue on signaling and predation-risk-sensitive foraging of a prey species, tufted titmice (Baeolophus bicolor).
View Article and Find Full Text PDFIn this paper we present amorphous chromium(III) hydride gels that show promise as reversible room temperature hydrogen storage materials with potential for exploitation in mobile applications. The material uses hydride ligands as a light weight structural feature to link chromium(III) metal centres together which act as binding sites for further dihydrogen molecules via the Kubas interaction, the mode of hydrogen binding confirmed by high pressure Raman spectroscopy. The best material possesses a reversible gravimetric storage of 5.
View Article and Find Full Text PDFObjective: Computation of a prearticulatory phonological representation (phonological access, or phonological retrieval) is an essential process in speech production whose neural localization is not clear. This study combined a specific behavioral measure of phonological access and multivariate voxel-based lesion-symptom mapping (VLSM) in a series of left hemisphere stroke patients to identify brain regions critical for this process.
Methods: Phonological access was assessed in 40 chronic ischemic stroke patients using a silent rhyming task to avoid confounds with motor planning and articulation deficits.
Faraday Discuss
April 2012
This project involved the conversion of a British Waterways maintenance craft to a canal boat, powered by a combination of a solid-state hydrogen store, Proton Exchange Membrane (PEM) fuel cell, lead-acid battery pack and a high-efficiency, permanent magnet (NdFeB) electric motor. These replaced the conventional diesel engine thus eliminating water, noise, local and general atmospheric pollution. The "Protium" project applies modern technologies to a traditional mode of transportation.
View Article and Find Full Text PDFPorous materials adsorb H2 through physisorption, a process which typically has a rather low enthalpy of adsorption (e.g. ca.
View Article and Find Full Text PDFQuick on the uptake: Following its identification during a targeted search, the intriguing crystal structure of 3,3',4,4'-tetra(trimethylsilylethynyl)biphenyl was investigated. Simple removal of the included solvent provides an organic crystal with an open microporous structure that has a striking similarity to that of zeolite A (see picture). Reversible adsorption of nitrogen and hydrogen gases at 77 K confirms that the microporosity is permanent.
View Article and Find Full Text PDFThe challenge of storing hydrogen at high volumetric and gravimetric density for automotive applications has prompted investigations into the potential of cryo-adsorption on the internal surface area of microporous organic polymers. A range of Polymers of Intrinsic Microporosity (PIMs) has been studied, the best PIM to date (a network-PIM incorporating a triptycene subunit) taking up 2.7% H(2) by mass at 10 bar/77 K.
View Article and Find Full Text PDFA novel triptycene-based polymer of intrinsic microporosity (Trip-PIM) displays enhanced surface area (1065 m2 g(-1)) and reversibly adsorbs 1.65% hydrogen by mass at 1 bar/77 K and 2.71% at 10 bar/77 K.
View Article and Find Full Text PDFWe report the discovery of a new, chemical route for 'activating' the hydrogen store MgH2, that results in highly effective hydrogen uptake/release characteristics, comparable to those obtained from mechanically-milled material.
View Article and Find Full Text PDFArch Otolaryngol Head Neck Surg
August 2003
Background: Office-based evaluation of the lower airway in adults with only topical anesthetics has been well documented. This study was performed to assess the feasibility of performing office-based lower airway endoscopy in a pediatric population.
Design: One hundred five consecutive pediatric patients requiring flexible laryngoscopy were studied.
Objectives/hypothesis: Quality of life (QOL) assessment of patients with nasal obstruction has not been well studied. The objectives of the study were to determine the QOL of patients with nasal obstruction, to identify baseline variables predictive of patients' QOL, and to examine the relationship of QOL scores with patient assessment of nasal obstruction.
Study Design: Preliminary, cross-sectional study of a larger, prospective investigation.