224 research outputs found

    Brain Potentials During Silent and Oral Reading

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    Brain potentials have been recorded during silence, during silent reading, and oral reading. While it has been assumed that potentials cannot be picked up during strong, complex stimulation, the results indicate that they can be. Analysis of the data indicates a hypothesis to the effect that complexity of cortical functioning is associated with complexity of the electrical activity of the cortex

    An Analysis of the Berger Rhythm, with Special Reference to the Duration and Amplitude of the Individual Wave

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    The rhythmical electrical potential waves recorded from the human brain have been classified by their discoverer, Berger2 into two types: alpha-waves, and beta-waves. This classification is made on the basis of the duration and amplitude of the waves. Waves having a duration of about .10 sec. and an amplitude of about 20 microvolts fall into the category of alpha-waves. Waves having a duration of about .04 sec. and an amplitude of about 10 microvolts make up the beta-waves. In general, the beta-wave is formed on the sides of the larger and more predominant alpha-wave

    Randomized multicentre pilot study of sacubitril/valsartan versus irbesartan in patients with chronic kidney disease: United Kingdom Heart and Renal Protection (HARP)- III—rationale, trial design and baseline data

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    BACKGROUND: Patients with chronic kidney disease (CKD) are at risk of progression to end-stage renal disease and cardiovascular disease. Data from other populations and animal experiments suggest that neprilysin inhibition (which augments the natriuretic peptide system) may reduce these risks, but clinical trials among patients with CKD are required to test this hypothesis. METHODS: UK Heart and Renal Protection III (HARP-III) is a multicentre, double-blind, randomized controlled trial comparing sacubitril/valsartan 97/103 mg two times daily (an angiotensin receptor-neprilysin inhibitor) with irbesartan 300 mg one time daily among 414 patients with CKD. Patients ≥18 years of age with an estimated glomerular filtration rate (eGFR) of ≥45 but <60 mL/min/1.73 m2 and urine albumin:creatinine ratio (uACR) >20 mg/mmol or eGFR ≥20 but <45 mL/min/1.73 m2 (regardless of uACR) were invited to be screened. Following a 4- to 7-week pre-randomization single-blind placebo run-in phase (during which any current renin-angiotensin system inhibitors were stopped), willing and eligible participants were randomly assigned either sacubitril/valsartan or irbesartan and followed-up for 12 months. The primary aim was to compare the effects of sacubitril/valsartan and irbesartan on measured GFR after 12 months of therapy. Important secondary outcomes include effects on albuminuria, change in eGFR over time and the safety and tolerability of sacubitril/valsartan in CKD. RESULTS: Between November 2014 and January 2016, 620 patients attended a screening visit and 566 (91%) entered the pre-randomization run-in phase. Of these, 414 (73%) participants were randomized (mean age 63 years; 72% male). The mean eGFR was 34.0 mL/min/1.73 m2 and the median uACR was 58.5 mg/mmol. CONCLUSIONS: UK HARP-III will provide important information on the short-term effects of sacubitril/valsartan on renal function, tolerability and safety among patients with CKD

    Final report on the force key comparison CCM.F-K3

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    In the Force Key Comparison CCM.F-K3 the measurand force was compared at the two force steps 500 kN and 1 MN. 12 laboratories participated in this comparison which was organised by PTB as the pilot laboratory in two laboratory groups (group A and B). In group A, the comparison was carried out with two 1 MN compression force transducers at the two force steps 500 kN and 1 MN (CCM.F-K3a) and with 6 participating laboratories. In group B, the comparison was carried out with two 500 kN compression force transducers at one force step of 500 kN (CCM.F-K3b) and with 9 participating laboratories. The key comparison reference values were determined as the weighted mean of all results for the two force steps and set to 500 kN and 1 MN, respectively, with the associated uncertainties. The degrees of equivalence were determined for all 12 laboratories for 500 kN compression force and for 6 laboratories for 1 MN compression force. KEY WORDS FOR SEARCH Force Key Comparison, high force, 500 kN, 1 MN Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA)

    Bridging the gaps among research, policy and practice in ten low- and middle-income countries: Development and testing of a questionnaire for health-care providers

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    <p>Abstract</p> <p>Background</p> <p>The reliability and validity of instruments used to survey health-care providers' views about and experiences with research evidence have seldom been examined.</p> <p>Methods</p> <p>Country teams from ten low- and middle-income countries (China, Ghana, India, Iran, Kazakhstan, Laos, Mexico, Pakistan, Senegal and Tanzania) participated in the development, translation, pilot-testing and administration of a questionnaire designed to measure health-care providers' views and activities related to improving their clinical practice and their awareness of, access to and use of research evidence, as well as changes in their clinical practice that they attribute to particular sources of research evidence that they have used. We use internal consistency as a measure of the questionnaire's reliability and, whenever possible, we use explanatory factor analyses to assess the degree to which questions that pertain to a single domain actually address common themes. We assess the questionnaire's face validity and content validity and, to a lesser extent, we also explore its criterion validity.</p> <p>Results</p> <p>The questionnaire has high internal consistency, with Cronbach's alphas between 0.7 and 0.9 for 16 of 20 domains and sub-domains (identified by factor analyses). Cronbach's alphas are greater than 0.9 for two domains, suggesting some item redundancy. Pre- and post-field work assessments indicate the questionnaire has good face validity and content validity. Our limited assessment of criterion validity shows weak but statistically significant associations between the general influence of research evidence among providers and more specific measures of providers' change in approach to preventing or treating a clinical condition.</p> <p>Conclusion</p> <p>Our analysis points to a number of strengths of the questionnaire - high internal consistency (reliability) and good face and content validity - but also to areas where it can be shortened without losing important conceptual domains.</p

    Learned vocal variation is associated with abrupt cryptic genetic change in a parrot species complex

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    <div><p>Contact zones between subspecies or closely related species offer valuable insights into speciation processes. A typical feature of such zones is the presence of clinal variation in multiple traits. The nature of these traits and the concordance among clines are expected to influence whether and how quickly speciation will proceed. Learned signals, such as vocalizations in species having vocal learning (e.g. humans, many birds, bats and cetaceans), can exhibit rapid change and may accelerate reproductive isolation between populations. Therefore, particularly strong concordance among clines in learned signals and population genetic structure may be expected, even among continuous populations in the early stages of speciation. However, empirical evidence for this pattern is often limited because differences in vocalisations between populations are driven by habitat differences or have evolved in allopatry. We tested for this pattern in a unique system where we may be able to separate effects of habitat and evolutionary history. We studied geographic variation in the vocalizations of the crimson rosella (<em>Platycercus elegans</em>) parrot species complex. Parrots are well known for their life-long vocal learning and cognitive abilities. We analysed contact calls across a <em>ca</em> 1300 km transect encompassing populations that differed in neutral genetic markers and plumage colour. We found steep clinal changes in two acoustic variables (fundamental frequency and peak frequency position). The positions of the two clines in vocal traits were concordant with a steep cline in microsatellite-based genetic variation, but were discordant with the steep clines in mtDNA, plumage and habitat. Our study provides new evidence that vocal variation, in a species with vocal learning, can coincide with areas of restricted gene flow across geographically continuous populations. Our results suggest that traits that evolve culturally can be strongly associated with reduced gene flow between populations, and therefore may promote speciation, even in the absence of other barriers.</p> </div

    Spaces of Yoga – Towards a Non-Essentialist Understanding of Yoga

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    This chapter will examine some of the spaces that yoga occupies in the contemporary world, both physical and social. By looking at yoga through the focus of particular, contested spaces and locations, it will be argued that overarching essentialist definitions of yoga are impossible, although individuals and social groups can and do create essentialist definitions that are more or less useful for particular purposes. By exploring these narratives and boundaries in the context of specific locations, we can better understand what people are doing with the collection of beliefs and practices known as yoga
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