2,173 research outputs found
Current practices, supports, and challenges in speech-language pathology service provision for autistic preschoolers
Background: Speech-language pathology services are among the most frequently accessed services for young autistic children. Therefore, understanding the nature of these services, what challenges these clinicians face, and what supports they value is critical for developing appropriate policies and practices that can maximize positive outcomes for children and families. This study had two primary aims. The first was to examine the self-reported assessment and intervention practices of community-based Speech Language Pathologists (SLPs) and communicative disorders assistants (CDAs; who provide services under the supervision of a SLP) in supporting preschool children with suspected and diagnosed autism. The second aim was to identify barriers and supports (facilitators) to providing services in the community using the Consolidated Framework for Implementation Research (CFIR) as a framework.
Methods: A cross-sectional online survey was used to collect qualitative and quantitative data from clinicians in Ontario Canada who were providing speech and language services to preschool children with suspected or diagnosed autism. Quantitative data were used to describe clinicians” practices, and qualitative data captured their perspectives on barriers and supports to providing services.
Results: A total of 258 clinicians participated in the survey. On average, clinicians reported almost half of the preschoolers on their caseload had either diagnosed or suspected autism. There was consistency across the skill development areas assessed by SLPs, and targeted during therapy sessions, with the top four areas targeted being: foundational social communication, language, play and pragmatics. However, there was wide variation in speech and language assessment and intervention practices reported by this sample of clinicians (i.e., service delivery models, tools or programs used, length and duration of therapy services, level of collaboration with other professionals). Clinicians identified several barriers to providing services: limited funding and time, lack of inter-professional collaboration, difficulty accessing services, community messaging about autism services, family readiness and clinician knowledge. Supports (facilitators) include access to autism-focused professional development, inter- and intra-professional collaboration, and access to additional supports in the communit
Relative luminosity measurement of the LHC with the ATLAS forward calorimeter
In this paper it is shown that a measurement of the relative luminosity
changes at the LHC may be obtained by analysing the currents drawn from the
high voltage power supplies of the electromagnetic section of the forward
calorimeter of the ATLAS detector. The method was verified with a reproduction
of a small section of the ATLAS forward calorimeter using proton beams of known
beam energies and variable intensities at the U-70 accelerator at IHEP in
Protvino, Russia. The experimental setup and the data taking during a test beam
run in April 2008 are described in detail. A comparison of the measured high
voltage currents with reference measurements from beam intensity monitors shows
a linear dependence on the beam intensity. The non-linearities are measured to
be less than 0.5 % combining statistical and systematic uncertainties.Comment: 16 page
Predictions from Heavy New Physics Interpretation of the Top Forward-Backward Asymmetry
We derive generic predictions at hadron colliders from the large
forward-backward asymmetry observed at the Tevatron, assuming the latter arises
from heavy new physics beyond the Standard Model. We use an effective field
theory approach to characterize the associated unknown dynamics. By fitting the
Tevatron t \bar t data we derive constraints on the form of the new physics.
Furthermore, we show that heavy new physics explaining the Tevatron data
generically enhances at high invariant masses both the top pair production
cross section and the charge asymmetry at the LHC. This enhancement can be
within the sensitivity of the 8 TeV run, such that the 2012 LHC data should be
able to exclude a large class of models of heavy new physics or provide hints
for its presence. The same new physics implies a contribution to the
forward-backward asymmetry in bottom pair production at low invariant masses of
order a permil at most.Comment: 11 pages, 6 figures. v2: added remarks on EFT validity range, dijet
bounds and UV completions; matches published versio
Can filesharers be triggered by economic incentives? Results of an experiment
Illegal filesharing on the internet leads to considerable financial losses for artists and copyright owners as well as producers and sellers of music. Thus far, measures to contain this phenomenon have been rather restrictive. However, there are still a considerable number of illegal systems, and users are able to decide quite freely between legal and illegal downloads because the latter are still difficult to sanction. Recent economic approaches account for the improved bargaining position of users. They are based on the idea of revenue-splitting between professional sellers and peers. In order to test such an innovative business model, the study reported in this article carried out an experiment with 100 undergraduate students, forming five small peer-to-peer networks.The networks were confronted with different economic conditions.The results indicate that even experienced filesharers hold favourable attitudes towards revenue-splitting.They seem to be willing to adjust their behaviour to different economic conditions
Remote Infrared Imaging of the Space Shuttle During Hypersonic Flight: HYTHIRM Mission Operations and Coordination
The Hypersonic Thermodynamic Infrared Measurements (HYTHIRM) project has been responsible for obtaining spatially resolved, scientifically calibrated in-flight thermal imagery of the Space Shuttle Orbiter during reentry. Starting with STS-119 in March of 2009 and continuing through to the majority of final flights of the Space Shuttle, the HYTHIRM team has to date deployed during seven Shuttle missions with a mix of airborne and ground based imaging platforms. Each deployment of the HYTHIRM team has resulted in obtaining imagery suitable for processing and comparison with computational models and wind tunnel data at Mach numbers ranging from over 18 to under Mach 5. This paper will discuss the detailed mission planning and coordination with the NASA Johnson Space Center Mission Control Center that the HYTHIRM team undergoes to prepare for and execute each mission
Are language production problems apparent in adults who no longer meet diagnostic criteria for attention-deficit/hyperactivity disorder?
In this study, we examined sentence production in a sample of adults (N = 21) who had had attention-deficit/hyperactivity disorder (ADHD) as children, but as adults no longer met DSM-IV diagnostic criteria (APA, 2000). This “remitted” group was assessed on a sentence production task. On each trial, participants saw two objects and a verb. Their task was to construct a sentence using the objects as arguments of the verb. Results showed more ungrammatical and disfluent utterances with one particular type of verb (i.e., participle). In a second set of analyses, we compared the remitted group to both control participants and a “persistent” group, who had ADHD as children and as adults. Results showed that remitters were more likely to produce ungrammatical utterances and to make repair disfluencies compared to controls, and they patterned more similarly to ADHD participants. Conclusions focus on language output in remitted ADHD, and the role of executive functions in language production
Human Immunodeficiency Virus Impairs Reverse Cholesterol Transport from Macrophages
Several steps of HIV-1 replication critically depend on cholesterol. HIV infection is associated with profound changes in lipid and lipoprotein metabolism and an increased risk of coronary artery disease. Whereas numerous studies have investigated the role of anti-HIV drugs in lipodystrophy and dyslipidemia, the effects of HIV infection on cellular cholesterol metabolism remain uncharacterized. Here, we demonstrate that HIV-1 impairs ATP-binding cassette transporter A1 (ABCA1)-dependent cholesterol efflux from human macrophages, a condition previously shown to be highly atherogenic. In HIV-1–infected cells, this effect was mediated by Nef. Transfection of murine macrophages with Nef impaired cholesterol efflux from these cells. At least two mechanisms were found to be responsible for this phenomenon: first, HIV infection and transfection with Nef induced post-transcriptional down-regulation of ABCA1; and second, Nef caused redistribution of ABCA1 to the plasma membrane and inhibited internalization of apolipoprotein A-I. Binding of Nef to ABCA1 was required for down-regulation and redistribution of ABCA1. HIV-infected and Nef-transfected macrophages accumulated substantial amounts of lipids, thus resembling foam cells. The contribution of HIV-infected macrophages to the pathogenesis of atherosclerosis was supported by the presence of HIV-positive foam cells in atherosclerotic plaques of HIV-infected patients. Stimulation of cholesterol efflux from macrophages significantly reduced infectivity of the virions produced by these cells, and this effect correlated with a decreased amount of virion-associated cholesterol, suggesting that impairment of cholesterol efflux is essential to ensure proper cholesterol content in nascent HIV particles. These results reveal a previously unrecognized dysregulation of intracellular lipid metabolism in HIV-infected macrophages and identify Nef and ABCA1 as the key players responsible for this effect. Our findings have implications for pathogenesis of both HIV disease and atherosclerosis, because they reveal the role of cholesterol efflux impairment in HIV infectivity and suggest a possible mechanism by which HIV infection of macrophages may contribute to increased risk of atherosclerosis in HIV-infected patients
Diabetes causes marked inhibition of mitochondrial metabolism in pancreatic β-cells
Diabetes is a global health problem caused primarily by the inability of pancreatic β-cells to secrete adequate levels of insulin. The molecular mechanisms underlying the progressive failure of β-cells to respond to glucose in type-2 diabetes remain unresolved. Using a combination of transcriptomics and proteomics, we find significant dysregulation of major metabolic pathways in islets of diabetic βV59M mice, a non-obese, eulipidaemic diabetes model. Multiple genes/proteins involved in glycolysis/gluconeogenesis are upregulated, whereas those involved in oxidative phosphorylation are downregulated. In isolated islets, glucose-induced increases in NADH and ATP are impaired and both oxidative and glycolytic glucose metabolism are reduced. INS-1 β-cells cultured chronically at high glucose show similar changes in protein expression and reduced glucose-stimulated oxygen consumption: targeted metabolomics reveals impaired metabolism. These data indicate hyperglycaemia induces metabolic changes in β-cells that markedly reduce mitochondrial metabolism and ATP synthesis. We propose this underlies the progressive failure of β-cells in diabetes.Peer reviewe
Two novel human cytomegalovirus NK cell evasion functions target MICA for lysosomal degradation
NKG2D plays a major role in controlling immune responses through the regulation of natural killer (NK) cells, αβ and γδ T-cell function. This activating receptor recognizes eight distinct ligands (the MHC Class I polypeptide-related sequences (MIC) A andB, and UL16-binding proteins (ULBP)1–6) induced by cellular stress to promote recognition cells perturbed by malignant transformation or microbial infection. Studies into human cytomegalovirus (HCMV) have aided both the identification and characterization of NKG2D ligands (NKG2DLs). HCMV immediate early (IE) gene up regulates NKGDLs, and we now describe the differential activation of ULBP2 and MICA/B by IE1 and IE2 respectively. Despite activation by IE functions, HCMV effectively suppressed cell surface expression of NKGDLs through both the early and late phases of infection. The immune evasion functions UL16, UL142, and microRNA(miR)-UL112 are known to target NKG2DLs. While infection with a UL16 deletion mutant caused the expected increase in MICB and ULBP2 cell surface expression, deletion of UL142 did not have a similar impact on its target, MICA. We therefore performed a systematic screen of the viral genome to search of addition functions that targeted MICA. US18 and US20 were identified as novel NK cell evasion functions capable of acting independently to promote MICA degradation by lysosomal degradation. The most dramatic effect on MICA expression was achieved when US18 and US20 acted in concert. US18 and US20 are the first members of the US12 gene family to have been assigned a function. The US12 family has 10 members encoded sequentially through US12–US21; a genetic arrangement, which is suggestive of an ‘accordion’ expansion of an ancestral gene in response to a selective pressure. This expansion must have be an ancient event as the whole family is conserved across simian cytomegaloviruses from old world monkeys. The evolutionary benefit bestowed by the combinatorial effect of US18 and US20 on MICA may have contributed to sustaining the US12 gene family
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