2,037 research outputs found
Virtual Reality Technologies and the Creative Arts in the Areas of Disability, Therapy, Health, and Rehabilitation
Structured evaluation of virtual environments for special-needs education
This paper describes the development of a structured approach to evaluate experiential and communication virtual learning environments (VLEs) designed specifically for use in the education of children with severe learning difficulties at the Shepherd special needs school in Nottingham, UK. Constructivist learning theory was used as a basis for the production of an evaluation framework, used to evaluate the design of three VLEs and how they were used by students with respect to this learning theory. From an observational field study of student-teacher pairs using the VLEs, 18 behaviour categories were identified as relevant to five of the seven constructivist principles defined by Jonassen (1994). Analysis of student-teacher behaviour was used to provide support for, or against, the constructivist principles. The results show that the three VLEs meet the constructivist principles in very different ways and recommendations for design modifications are put forward
Formalism for dilepton production via virtual photon bremsstrahlung in hadronic reactions
We derive a set of new formulas for various distributions in dilepton
production via virtual photon bremsstrahlung from pseudoscalar mesons and
unpolarized spin-one-half fermions. These formulas correspond to the leading
and sub-leading terms in the Low-Burnett-Kroll expansion for real photon
bremsstrahlung. The relation of our leading-term formulas to previous works is
also shown. Existing formulas are examined in the light of Lorentz covariance
and gauge invariance. Numerical comparison is made in a simple example, where
an "exact" formula and real photon data exist. The results reveal large
discrepancies among different bremsstrahlung formulas. Of all the leading-term
bremsstrahlung formulas, the one derived in this work agrees best with the
exact formula. The issues of M_T-scaling and event generators are also
addressed.Comment: 37 pages, RevTeX, epsf.sty, 10 embedded figure
Development of mobile sensors for estimation of grain qualities and contaminants to enhance nutrition and safety of grain-products in developing countries; current status
The governments of several developing countries responded to their population “malnutrition crisis” (P.Webb et al., 2018), among others, by promotion of crops of high nutritional value and their enhanced usage for food products formulations (e.g. “Millet Mission” in India or “Blending Policy” in Kenya). Simultaneously, several CGIAR crop improvement programs-initiated the development of nutritionally enhanced crop cultivars (e.g. ICRISAT, CIAT, IIT). In developing countries, the promotion of novel cultivars is generally a slow and tedious process, especially if the improved grain (quantity or quality) doesn’t ultimately result in the economic incentives (e.g. the market price). Thus far, there is no economic advantage directly linked to the trade of bio-fortified crop cultivars in developing countries which does prevents their accelerated adoption. This may change if/once the necessary information on a crops value is enabled
“When my Autism Broke”: A Qualitative Study Spotlighting Autistic Voices on Menopause
Autistic women often struggle with the onset of menstruation, a key transition point in the female reproductive lifespan. Presently, there is no research investigating how autistic people navigate the menopausal transition, and whether it poses additional challenges in addition to those already faced by neurotypical women. As a preliminary participatory study in this area, we conducted an online focus group with seven autistic individuals, aged 49-63 years (median=64.5 years) and assigned female at birth, to explore the state of knowledge about the menopause in autism, difficulties the menopause might bring, support that might be needed, and what questions require scientific investigation. Thematic analysis of the discussion generated three themes: 1)Lack of knowledge and understanding; 2)Cracking the mask and adaptive functioning; and 3)Finding support. Themes suggested a lack of professional knowledge, understanding and communication about menopause for autistic people, and an absence of support. Menopause was discussed as heightening pre-existing and generating new cognitive, social, emotional and sensory difficulties. This study illustrates the need for greater focus of attention towards how autistic people cope with the major life transition of menopause
Mapping between dissipative and Hamiltonian systems
Theoretical studies of nonequilibrium systems are complicated by the lack of
a general framework. In this work we first show that a transformation
introduced by Ao recently (J. Phys. A {\bf 37}, L25 (2004)) is related to
previous works of Graham (Z. Physik B {\bf 26}, 397 (1977)) and Eyink {\it et
al.} (J. Stat. Phys. {\bf 83}, 385 (1996)), which can also be viewed as the
generalized application of the Helmholtz theorem in vector calculus. We then
show that systems described by ordinary stochastic differential equations with
white noise can be mapped to thermostated Hamiltonian systems. A steady-state
of a dissipative system corresponds to the equilibrium state of the
corresponding Hamiltonian system. These results provides a solid theoretical
ground for corresponding studies on nonequilibrium dynamics, especially on
nonequilibrium steady state. The mapping permits the application of established
techniques and results for Hamiltonian systems to dissipative non-Hamiltonian
systems, those for thermodynamic equilibrium states to nonequilibrium steady
states. We discuss several implications of the present work.Comment: 18 pages, no figure. final version for publication on J. Phys. A:
Math & Theo
Physical and mental health correlates of status incongruence
The report explored the relationship between status incongruence, the degree of similarity of rankings on paired status variables, and diverse interview-based measures of physical and mental health. The subjects in the study were some 169 adult men; one half of them came from a national survey sample, while the other half represented an arthritis clinic sample with patients and controls. Data on education, occupation, income, and perceived social class (PSC) were used to construct several status incongruence indices. The major findings were: 1. Neither rheumatoid arthritis nor ulcer were related to status incongruence. 2. Education-occupation incongruence showed by far the strongest association with poor mental health. Among the two types of incongruence, education > occupation and occupation > education, the former had particularly poor mental health. 3. Education-PSC, occupation-PSC, education-income, and occupation-income types of incongruence showed weaker associations. Direction of incongruence made a difference in the education-PSC comparison: the education > PSC incongruent group had poorer mental health than the PSC > education incongruent group. Ce rapport étudie la relation entre la discordance du status («status incongruence»), le degré de similitude d'évaluation de variables couplées du status et diverses mesures de la santé physique et mentale basées sur des interviews. Les sujets de l'étude étaient 169 hommes adultes dont la moitié provenait d'un échantillon d'une investigation nationale, tandis que l'autre moitié représentait un échantillon d'une clinique d'arthritiques avec des patients et des cas de contrôle. Des données sur l'éducation, l'occupation, le revenu et la classe sociale (perceived social class = PSC) furent utilisées pour l'élaboration de divers indices de discordance de status. Les résultats principaux furent: 1) Ni l'arthrite rhumatoïde ni l'ulcère n'étaient reliés à la discordance du status. 2) La discordance éducation-occupation était de loin la plus étroitement associée à une santé mentale défaillante. Parmi les deux types de discordance, éducation > occupation et occupation > éducation, le premier était caractérisé par une santé mentale particulièrement mauvaise. 3) Les types de discordance éducation-PSC, occupation-PSC, éducation-revenu et occupationrevenu étaient plus faiblement associés. La direction de la discordance faisait une différence dans la comparaison éducationPSC: le groupe de discordance éducation > PSC se distinguait par une santé mentale moins bonne que le groupe de discordance PSC > éducation. Der Bericht gibt die Untersuchung der Beziehung zwischen der Unausgeglichenheit innerhalb des Sozialstands, dem Ausmaß der Ähnlichkeit von Einstufungen durch vorgegebene Gegensatzpaare von Statusmerkmalen und verschiedenen, auf Interviewbasis begründeten Einschätzungen der körperlichen und seelischen Gesundheit wieder. Die Probanden der Studie waren 169 erwachsene Männer; die Hälfte von ihnen stammte aus einer staatlichen Begutachtungsgruppe, die andere Hälfte verkörperten Patienten und Kontrollpersonen aus einer Arthritisklinik. Daten über Erziehung, Beruf, Einkommen und beurteilte Sozialklasse (perceived social class = PSC) wurden verwandt, um mehrere Indices für Statusinkongruenz zu bilden. Die Hauptergebnisse waren: 1) Weder rheumatische Arthritis noch Ulcus standen in Beziehung mit Statusinkongruenz. 2) Ein Mißverhältnis zwischen Erziehung und Beruf zeigte bei weitem die engste Beziehung zu schlechter seelischer Gesundheit. Von den beiden Inkongruenztypen, Erziehung > Beruf und Beruf > Erziehung, hatte der erste eine besonders schlechte seelische Gesundheit. 3) Mißverhältnisse zwischen Erziehung und PSC, Beruf und PSC, Erziehung und Einkommen und Beruf und Einkommen zeigten schwächere Beziehungen. Die Richtung der Inkongruenz bewirkte einen Unterschied im Vergleich zwischen Erziehung und PSC: die inkongruente Gruppe Erziehung > PSC war bei schlechterer seelischer Gesundheit als die inkongruente Gruppe PSC > Erziehung.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41742/1/127_2004_Article_BF00584107.pd
Initial results from a realtime FRB search with the GBT
We present the data analysis pipeline, commissioning observations and initial
results from the GREENBURST fast radio burst (FRB) detection system on the
Robert C. Byrd Green Bank Telescope (GBT) previously described by Surnis et al.
which uses the 21~cm receiver observing commensally with other projects. The
pipeline makes use of a state-of-the-art deep learning classifier to winnow
down the very large number of false positive single-pulse candidates that
mostly result from radio frequency interference. In our observations totalling
156.5 days so far, we have detected individual pulses from 20 known radio
pulsars which provide an excellent verification of the system performance. We
also demonstrate, through blind injection analyses, that our pipeline is
complete down to a signal-to-noise threshold of 12. Depending on the observing
mode, this translates to peak flux sensitivities in the range 0.14--0.89~Jy.
Although no FRBs have been detected to date, we have used our results to update
the analysis of Lawrence et al. to constrain the FRB all-sky rate to be
per day above a peak flux density of 1~Jy. We also
constrain the source count index which indicates that the
source count distribution is substantially flatter than expected from a
Euclidean distribution of standard candles (where ). We discuss
this result in the context of the FRB redshift and luminosity distributions.
Finally, we make predictions for detection rates with GREENBURST, as well as
other ongoing and planned FRB experiments.Comment: 9 pages, 7 figures, submitted to MNRA
Long-Term Studies Reveal Differential Responses to Climate Change for Trees Under Soil- or Herbivore-Related Stress
Worldwide, trees are confronting increased temperature and aridity, exacerbating susceptibility to herbivory. Long-term studies comparing patterns of plant performance through drought can help identify variation among and within populations in vulnerability to climate change and herbivory. We use long-term monitoring data to examine our overarching hypothesis that the negative impacts of poor soil and herbivore susceptibility would be compounded by severe drought. We studied pinyon pine, Pinus edulis, a widespread southwestern tree species that has suffered extensive climate-change related mortality. We analyzed data on mortality, growth, male reproduction, and herbivory collected for 14–32 years in three areas with distinct soil-types. We used standardized precipitation-evapotranspiration index (SPEI) as a climate proxy that summarizes the impacts of drought due to precipitation and temperature variation on semi-arid forests. Several key findings emerged: (1) Plant performance measurements did not support our hypothesis that trees growing in stressful, coarse-textured soils would suffer more than trees growing in finer-textured soils. Stem growth at the area with coarse, young cinder soils (area one) responded only weakly to drought, while stem growth on more developed soils with sedimentary (area two) and volcanic (area three) substrates, was strongly negatively affected by drought. Male reproduction declined less with drought at area one and more at areas two and three. Overall mortality was 30% on coarse cinder soils (area one) and averaged 55% on finer soil types (areas two and three). (2) Although moth herbivore susceptible trees were hypothesized to suffer more with drought than moth resistant trees, the opposite occurred. Annual stem growth was negatively affected by drought for moth resistant trees, but much less strongly for moth susceptible trees. (3) In contrast to our hypothesis, moths declined with drought. Overall, chronically water-stressed and herbivore-susceptible trees had smaller declines in performance relative to less-stressed trees during drought years. These long-term findings support the idea that stressed trees might be more resistant to drought since they may have adapted or acclimated to resist drought-related mortality
The Optical SN 2012bz Associated with the Long GRB 120422A
The association of Type Ic SNe with long-duration GRBs is well established.
We endeavor, through accurate ground-based observational campaigns, to
characterize these SNe at increasingly high redshifts. We obtained a series of
optical photometric and spectroscopic observations of the Type Ic SN2012bz
associated with the Swift long-duration GRB120422A (z=0.283) using the 3.6-m
TNG and the 8.2-m VLT telescopes. The peak times of the light curves of
SN2012bz in various optical filters differ, with the B-band and i'-band light
curves reaching maximum at ~9 and ~23 rest-frame days, respectively. The
bolometric light curve has been derived from individual bands photometric
measurements, but no correction for the unknown contribution in the
near-infrared (probably around 10-15%) has been applied. Therefore, the present
light curve should be considered as a lower limit to the actual UV-optical-IR
bolometric light curve. This pseudo-bolometric curve reaches its maximum (Mbol
= -18.56 +/- 0.06) at 13 +/- 1 rest-frame days; it is similar in shape and
luminosity to the bolometric light curves of the SNe associated with z<0.2 GRBs
and more luminous than those of SNe associated with XRFs. A comparison with the
model generated for the bolometric light curve of SN2003dh suggests that
SN2012bz produced only about 15% less 56Ni than SN2003dh, about 0.35 Msol.
Similarly the VLT spectra of SN2012bz, after correction for Galactic extinction
and for the contribution of the host galaxy, suggest comparable explosion
parameters with those observed in SN2003dh (EK~3.5 x 10^52 erg, Mej~7 Msol) and
a similar progenitor mass (~25-40 Msol). GRB120422A is consistent with the
Epeak-Eiso and the EX,iso-Egamma,iso-E_peak relations. GRB120422A/SN2012bz
shows the GRB-SN connection at the highest redshift so far accurately monitored
both photometrically and spectroscopically.Comment: 7 pages, 6 figures, 2 tables, accepted for publication in Astronomy &
Astrophysic
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