260 research outputs found
Feasibility and preliminary efficacy of motivating eye gaze in young children on autism spectrum through parent-mediated intervention
We studied the feasibility and preliminary efficacy of a brief parent-mediated intervention to improve the orienting towards faces in young autistic children. Twenty (aged 3â6) autistic children were randomly assigned to an intervention or a control group. The intervention group parents were trained to perform three types of practices with their children for four months. The feasibility of recruitment, data collection and analysis procedures, acceptability and adherence were investigated. To study the usability and preliminary efficacy of two outcome measures, eye gaze and state of engagement with parents were observed during a 10-minute free-play session at baseline, after 4â6 months, and after two years. The results indicated support for the feasibility and efficacy, demonstrating a significant increase in eye gaze and engagement in the intervention group but not in the control group. It is an encouraging preliminary finding that the engagement increased after supporting the orientation towards the eye region, indicating beneficial effects for further social-communicative development in autistic children.publishedVersionPeer reviewe
Is there diquark clustering in the nucleon?
It is shown that the instanton-induced interaction in qq pairs, iterated in
t-channel, leads to a meson-exchange interactions between quarks. In this way
one can achieve a simultaneous understanding of low-lying mesons, baryons and
the nuclear force. The discussion is general and does not necessarily rely on
the instanton-induced interaction. Any nonperturbative gluonic interaction
between quarks, which is a source of the dynamical chiral symmetry breaking and
explains the - mass splitting, will imply an effective meson
exchange picture in baryons. Due to the (anti)screening there is a big
difference between the initial 't Hooft interaction and the effective
meson-exchange interaction. It is demonstrated that the effective
meson-exchange interaction, adjusted to the baryon spectrum, does not bind the
scalar diquark and does not induce any significant quark-diquark clustering in
the nucleon because of the nontrivial role played by the Pauli principle.Comment: Final version to appear in Phys. Rev. D; typos have been corrected;
some formulae have been written in a more detailed form; some references have
been update
Going carless in different urban fabrics : socio-demographics of household car ownership
Diverse physical features of urban areas alongside socio-demographic characteristics affect car ownership, and hence the daily mobility choices. As a case of sustainable mobility, we explore how various urban environments and socio-demographics associate with the spatial and social distribution of household car ownership and carlessness in the Helsinki Metropolitan Area, Finland. Three urban fabrics characterizing the study area are established based on the transportation mode (walking, public transportation, or automobile) the physical urban environment primarily supports. The national level Monitoring System of Spatial Structure and Urban Form database, and the National Travel Survey (2016) are utilized to further include spatial and socio-demographic variables into our analysis across these fabrics. Our results show that households with and without cars differ in terms of residential distance to the city center, neighborhood density, house type, and socio-demographic profiles. Single pensioners and students are most likely to be carless, whereas families represent the opposite. Within the carless households the differences are also evident between different groups. For the more affluent households residing in dense and well-connected areas, and mostly possessing driver's licenses, carlessness is presumably a choice. Contrarily, many other carless households represent the less affluent often located in the more distant, low-density, and less accessible areas, while also possessing less driver's licenses, making carlessness more of a constraint, as the local urban fabric does not support such lifestyle. Consequently, carless households should be increasingly recognized as a focus group in sustainable urban planning in terms of identifiable best practices and potential vulnerability.Peer reviewe
Meson exchange and nucleon polarizabilities in the quark model
Modifications to the nucleon electric polarizability induced by pion and
sigma exchange in the q-q potentials are studied by means of sum rule
techniques within a non-relativistic quark model. Contributions from meson
exchange interactions are found to be small and in general reduce the quark
core polarizability for a number of hybrid and one-boson-exchange q-q models.
These results can be explained by the constraints that the baryonic spectrum
impose on the short range behavior of the mesonic interactions.Comment: 11 pages, 1 figure added, expanded discussio
The Gluon Exchange Interaction Between Constituent Quarks
The interaction mediated by irreducible pion and gluon exchange between
constituent quarks is calculated and shown to have a strong tensor component,
which tends to cancel the pion exchange tensor interaction between quarks. Its
spin-spin component is somewhat weaker than the pion exchange spin-spin
interaction, while its central and spin-orbit components are small in
comparison to the corresponding single gluon exchange interactions. The
combination of the gluon exchange interaction with the single pion
exchange interaction and a weak gluon exchange interaction between constituent
quarks has the qualitative features required for understanding the hyperfine
splittings of the spectra of the nucleon and the resonances.Comment: LaTeX, 17 pages, 5 Postscript figure
Penta-quark states with hidden charm and beauty
More and more hadron states are found to be difficult to be accommodated by
the quenched quark models which describe baryons as 3-quark states and mesons
as antiquark-quark states. Dragging out an antiquark-quark pair from the gluon
field in hadrons should be an important excitation mechanism for hadron
spectroscopy. Our recent progress on the penta-quark states with hidden charm
and beauty is reviewed.Comment: Plenary talk at the 5th Asia-Pacific Conference on Few-Body Problems
in Physics 2011 (APFB2011), 22-26 Aug., 2011, Seoul, Kore
Going carless in different urban fabrics: socio-demographics of household car ownership
Diverse physical features of urban areas alongside socio-demographic characteristics affect car ownership, and hence the daily mobility choices. As a case of sustainable mobility, we explore how various urban environments and socio-demographics associate with the spatial and social distribution of household car ownership and carlessness in the Helsinki Metropolitan Area, Finland. Three urban fabrics characterizing the study area are established based on the transportation mode (walking, public transportation, or automobile) the physical urban environment primarily supports. The national level Monitoring System of Spatial Structure and Urban Form database, and the National Travel Survey (2016) are utilized to further include spatial and socio-demographic variables into our analysis across these fabrics. Our results show that households with and without cars differ in terms of residential distance to the city center, neighborhood density, house type, and socio-demographic profiles. Single pensioners and students are most likely to be carless, whereas families represent the opposite. Within the carless households the differences are also evident between different groups. For the more affluent households residing in dense and well-connected areas, and mostly possessing driver's licenses, carlessness is presumably a choice. Contrarily, many other carless households represent the less affluent often located in the more distant, low-density, and less accessible areas, while also possessing less driver's licenses, making carlessness more of a constraint, as the local urban fabric does not support such lifestyle. Consequently, carless households should be increasingly recognized as a focus group in sustainable urban planning in terms of identifiable best practices and potential vulnerability
Z^* Resonances: Phenomenology and Models
We explore the phenomenology of, and models for, the Z^* resonances, the
lowest of which is now well established, and called the Theta. We provide an
overview of three models which have been proposed to explain its existence
and/or its small width, and point out other relevant predictions, and potential
problems, for each. The relation to what is known about KN scattering,
including possible resonance signals in other channels, is also discussed.Comment: 29 pages, uses RevTeX4; expanded version (published form
Tumour necrosis factor gene polymorphism: a predictive factor for the development of post-transplant lymphoproliferative disease
EpsteinâBarr virus-positive post-transplant lymphoproliferative disease (PTLD) is a potentially lethal complication of iatrogenic immunosupression after transplantation. Predicting the development of PTLD allowing early and effective intervention is therefore of importance. Polymorphisms within cytokine genes are implicated in susceptibility to, and progression of, disease however the published data are often conflicting. We undertook investigation of polymorphic alleles within cytokine genes in PTLD and non-PTLD transplant cohorts to determine risk factors for disease.
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Methods:
SSP-PCR was used to analyse single nucleotide polymorphism within tumour necrosis factor (TNF)-α, interleukin- 1, -6, -10 and lymphotoxin-α genes. The TNF-α levels were measured by standard enzyme-linked immuno-absorbant assay.
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Results:
We show an association between variant alleles within the TNF-α promoter (â1031C (<i>P</i>=0.005)); â863A (<i>P</i>=0.0001) and TNF receptor I promoter regions (â201T (<i>P</i>=0.02)); â1135C (<i>P</i>=0.03) with the development of PTLD. We also show an association with TNF-α promoter haplotypes with haplotype-3 significantly increased (<i>P</i>=0.0001) and haplotype-1 decreased (P=0.02) in PTLD patients compared to transplant controls. Furthermore, we show a significant increase (<i>P</i>=0.02) in the level of TNF-α in PTLD patient plasma (range 0â97.97 pg ml<sup>â1</sup>) compared to transplant controls (0â8.147 pg ml<sup>â1</sup>), with the highest levels found in individuals carrying the variant alleles.
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Conclusion:
We suggest that genetic variation within TNF-α loci and the level of plasma cytokine could be used as a predictive risk factor for the development of PTLD
Integration of safety in IFMIF-DONES design
The IFMIF-DONES (International Fusion Material Irradiation Facility-DEMO Oriented NEutron Source) facility is being designed with the general objective of providing irradiation of representative samples of power fusion machine materials under prototypical conditions. A linear accelerator will deliver deuterons at high intensity to circulating lithium in a loop, which will produce neutrons capable of obtaining the required damage conditions. As a result of this process, radionuclides will be produced as a by-product, which is characterized by several degrees of mobility. Shielding and radiation protection measures will be required in the facility. IFMIF-DONES will be classified as a first class radioactive facility according to national regulations, with Spain being the European candidate to site the facility. Several aspects of the main safety instructions affecting the facilityâs design are explained and discussed in this pape
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