83 research outputs found
A Synthetic Tone-Mixer
A device designed to demonstrate the phenomenon of tone-mixing will be exhibited and described. By means of this apparatus a vibrato may be synthetically produced with the number of pulses per second, extent of frequency fluctuation, and intensity relationship under control. The manner in which each of these variables influences the perceived tone can thus be determined. It is also possible to reproduce a vibrato whose rate, extent, and intensity relationship are identical with those of artistic singing. One factor at a time can then be varied and the relative importance of the several elements in the artistic tone determined. The device is also very convenient for demonstrating in the classroom the principle of sonance
Basic Differences in Pitch, Intensity, and Time Between Good and Poor Voices During Speech
This investigation involves the photography of pitch, intensity, and duration changes in about 80 poor speaking voices and 60 good speaking voices to ascertain basic differences that will indicate procedures for remedial purposes. The voices studied were the best and the poorest among 970 freshmen at the University of Iowa as rated and described by speech pathologists of the university staff. By means of a procedure worked out by Tiffin and others, a synonymous intensity, a pitch, and duration record of each syllable is photographed on a single strip of sensitized paper six inches wide
Central Determinants of Peripheral Manifestations in Reading
Numerous investigations have shown that poor reading is accompanied by irregularities in the eye-movements of the reader. The most marked of these is regressive movement, that is, backward movement of the eyes to places previously looked at. Clinicians in remedial reading have been much struck by the presence of these irregularities, and have sometimes attempted to improve reading by treating the eye-movements as such. The question investigated by this research is: Do irregular eye-movements cause poor reading, or does poor reading cause irregular eye-movements? If poor reading is shown to be the cause of poor eye-movements, then it is obviously fallacious to attempt the improvement of reading by working on the eye-movements
A Photographic Study of the Use of Intensity by Superior Speakers
This report covers the first study in a series now being made for the purpose of determining the basic characteristics of superior speech
Exploring structural variation and gene family architecture with De Novo assemblies of 15 Medicago genomes
Abstract Background Previous studies exploring sequence variation in the model legume, Medicago truncatula, relied on mapping short reads to a single reference. However, read-mapping approaches are inadequate to examine large, diverse gene families or to probe variation in repeat-rich or highly divergent genome regions. De novo sequencing and assembly of M. truncatula genomes enables near-comprehensive discovery of structural variants (SVs), analysis of rapidly evolving gene families, and ultimately, construction of a pan-genome. Results Genome-wide synteny based on 15 de novo M. truncatula assemblies effectively detected different types of SVs indicating that as much as 22% of the genome is involved in large structural changes, altogether affecting 28% of gene models. A total of 63 million base pairs (Mbp) of novel sequence was discovered, expanding the reference genome space for Medicago by 16%. Pan-genome analysis revealed that 42% (180 Mbp) of genomic sequences is missing in one or more accession, while examination of de novo annotated genes identified 67% (50,700) of all ortholog groups as dispensable â estimates comparable to recent studies in rice, maize and soybean. Rapidly evolving gene families typically associated with biotic interactions and stress response were found to be enriched in the accession-specific gene pool. The nucleotide-binding site leucine-rich repeat (NBS-LRR) family, in particular, harbors the highest level of nucleotide diversity, large effect single nucleotide change, protein diversity, and presence/absence variation. However, the leucine-rich repeat (LRR) and heat shock gene families are disproportionately affected by large effect single nucleotide changes and even higher levels of copy number variation. Conclusions Analysis of multiple M. truncatula genomes illustrates the value of de novo assemblies to discover and describe structural variation, something that is often under-estimated when using read-mapping approaches. Comparisons among the de novo assemblies also indicate that different large gene families differ in the architecture of their structural variation
100 Years of Scientific Evolution of Work and Organizational Psychology: A Bibliometric Network Analysis From 1919 to 2019
In this study, we explore a 100 years of Work and Organizational Psychology (WOP). To do this, we carry out a bibliometric performance and network analysis (BPNA) to understand the evolution structure and the most important themes in the field of study. To perform the BNPA, 8,966 documents published since 1919 were exported from the Web of Science and Scopus databases. The SciMAT software was used to process data and to create the evolution structure, the strategic diagram, and the thematic network structure of the strategic themes of the field of WOP. We identified 29 strategic clusters and discuss the most important themes (motor themes) and their relationship with other clusters. This research presents the complete evolution of the field of study, identifying emerging themes and others with a high degree of development. We hope that this work will support researchers and future research in the field of WOP
Evolutionary Dynamics of Human Toll-Like Receptors and Their Different Contributions to Host Defense
Infectious diseases have been paramount among the threats to health and survival throughout human evolutionary history. Natural selection is therefore expected to act strongly on host defense genes, particularly on innate immunity genes whose products mediate the direct interaction between the host and the microbial environment. In insects and mammals, the Toll-like receptors (TLRs) appear to play a major role in initiating innate immune responses against microbes. In humans, however, it has been speculated that the set of TLRs could be redundant for protective immunity. We investigated how natural selection has acted upon human TLRs, as an approach to assess their level of biological redundancy. We sequenced the ten human TLRs in a panel of 158 individuals from various populations worldwide and found that the intracellular TLRsâactivated by nucleic acids and particularly specialized in viral recognitionâhave evolved under strong purifying selection, indicating their essential non-redundant role in host survival. Conversely, the selective constraints on the TLRs expressed on the cell surfaceâactivated by compounds other than nucleic acidsâhave been much more relaxed, with higher rates of damaging nonsynonymous and stop mutations tolerated, suggesting their higher redundancy. Finally, we tested whether TLRs have experienced spatially-varying selection in human populations and found that the region encompassing TLR10-TLR1-TLR6 has been the target of recent positive selection among non-Africans. Our findings indicate that the different TLRs differ in their immunological redundancy, reflecting their distinct contributions to host defense. The insights gained in this study foster new hypotheses to be tested in clinical and epidemiological genetics of infectious disease
Health, education, and social care provision after diagnosis of childhood visual disability
Aim: To investigate the health, education, and social care provision for children newly diagnosed with visual disability.Method: This was a national prospective study, the British Childhood Visual Impairment and Blindness Study 2 (BCVIS2), ascertaining new diagnoses of visual impairment or severe visual impairment and blindness (SVIBL), or equivalent vi-sion. Data collection was performed by managing clinicians up to 1-year follow-up, and included health and developmental needs, and health, education, and social care provision.Results: BCVIS2 identified 784 children newly diagnosed with visual impairment/SVIBL (313 with visual impairment, 471 with SVIBL). Most children had associated systemic disorders (559 [71%], 167 [54%] with visual impairment, and 392 [84%] with SVIBL). Care from multidisciplinary teams was provided for 549 children (70%). Two-thirds (515) had not received an Education, Health, and Care Plan (EHCP). Fewer children with visual impairment had seen a specialist teacher (SVIBL 35%, visual impairment 28%, Ï2p < 0.001), or had an EHCP (11% vs 7%, Ï2p < 0 . 01).Interpretation: Families need additional support from managing clinicians to access recommended complex interventions such as the use of multidisciplinary teams and educational support. This need is pressing, as the population of children with visual impairment/SVIBL is expected to grow in size and complexity.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited
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