307 research outputs found
Use of Active Video Gaming in Children with Neromotor Dysfunction: A Systematic Review
Background and Purpose: Active video games (AVG) are gaining popularity as a strategy for improving motor function in children with neurologically-based movement disorders, but there is no consensus regarding AVG’s utility or effectiveness in this population. The purpose of this systematic review was to examine current evidence on the use of AVG to improve motor function in children 2-17 years of age with neurologically-based movement disorders. Methods: Authors followed standard criteria for systematic review conduct and rating quality of evidence including the PRISMA checklist. Databases searched were Scopus, MEDLINE, Cochrane Library, EMBASE, and CINAHL. Systematic reviews, randomized control trials, or longitudinal studies were included if they investigated AVG for improving movement-related outcomes in children aged 2-17 years with neurologically-based movement disorders. Parameters studied included: health condition, strength of evidence, delivery methods or systems for AVG, capacity for adjusting to individual needs and skill levels, outcomes addressed with AVG, effectiveness for achieving targeted outcomes [primarily activity-level motor outcomes (n=36)], and challenges/limitations. Results: The 20 articles included in the review varied in quality from high (n=6), to moderate (n=4) to low (n=8) with two strong quality single subject research design (SSRD) studies. Studies involved children with 6 neurologic conditions using AVG in clinical, home or school settings for 49 different outcomes. Frequency and duration of dosage varied. Choice of games played and difficulty level were controlled by therapists (n=6) or the child (n=14). The most commonly reported limitations were small sample sizes and difficulty providing task-specific practice of functional movements via AVG. All studies reported improvement with AVG, though differences were not consistently significant compared to traditional therapy. Discussion: Heterogeneity of measurement tools and target outcomes prevented meta-analysis or development of formal recommendations. However, AVG has demonstrated feasibility and shows potential for improving activity-level outcomes (including those assessing balance, gross motor function, and upper and lower limb function) of children with neuromotor disorders, and should be considered when developing plans of care for this population. Additional research with larger samples, and investigations that explore dosing variables and utility for extending practice by home programming are merited
The KPNO International Spectroscopic Survey. IV. H-alpha-selected Survey List 2
The KPNO International Spectroscopic Survey (KISS) is an objective-prism
survey for extragalactic emission-line objects. It combines many of the
features of previous slitless spectroscopic surveys with the advantages of
modern CCD detectors, and is the first purely digital objective-prism survey
for emission-line galaxies. Here we present the second list of emission-line
galaxy candidates selected from our red spectral data, which cover the
wavelength range 6400 to 7200 A. In most cases, the detected emission line is
H-alpha. The current survey list covers a 1.6-degree-wide strip located at
Dec(1950) = 43d 30' and spans the RA range 11h 55m to 16h 15m. The survey strip
runs through the center of the Bootes Void, and has enough depth to adequately
sample the far side of the void. An area of 65.8 sq. deg. is covered. A total
of 1029 candidate emission-line objects have been selected for inclusion in the
survey list (15.6 per sq. deg.). We tabulate accurate coordinates and
photometry for each source, as well as estimates of the redshift and
emission-line flux and equivalent width based on measurements of the digital
objective-prism spectra. The properties of the KISS emission-line galaxies are
examined using the available observational data. Although the current survey
covers only a modest fraction of the total volume of the Bootes Void, we
catalog at least twelve objects that appear to be located within the void. Only
one of these objects has been recognized previously as a void galaxy.Comment: Accepted for publication in the Astronomical Journal (April 2004); 20
pages, 12 figure
Environmental Enrichment: Disentangling the Influence of Novelty, Social, and Physical Activity on Cerebral Amyloid Angiopathy in a Transgenic Mouse Model
Cerebral amyloid angiopathy (CAA) is the deposition of amyloid protein in the cerebral vasculature, a common feature in both aging and Alzheimer’s disease (AD). However, the effects of environmental factors, particularly cognitive stimulation, social stimulation, and physical activity, on CAA pathology are poorly understood. These factors, delivered in the form of the environmental enrichment (EE) paradigm in rodents, have been shown to have beneficial effects on the brain and behavior in healthy aging and AD models. However, the relative importance of these subcomponents on CAA pathology has not been investigated. Therefore, we assessed the effects of EE, social enrichment (SOC), and cognitive enrichment (COG) compared to a control group that was single housed without enrichment (SIN) from 4 to 8 months of age in wild-type mice (WT) and Tg-SwDI mice, a transgenic mouse model of CAA that exhibits cognitive/behavioral deficits. The results show that individual facets of enrichment can affect an animal model of CAA, though the SOC and combined EE conditions are generally the most effective at producing physiological, cognitive/behavioral, and neuropathological changes, adding to a growing literature supporting the benefits of lifestyle interventions
Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: III. Emission Line Diagnostics of Ensembles of Evolving HII Regions
We build, as far as theory will permit, self consistent model HII regions
around central clusters of aging stars. These produce strong emission line
diagnostics applicable to either individual HII regions in galaxies, or to the
integrated emission line spectra of disk or starburst galaxies. The models
assume that the expansion and internal pressure of individual HII regions is
driven by the net input of mechanical energy from the central cluster, be it
through winds or supernova events. This eliminates the ionization parameter as
a free variable, replacing it with a parameter which depends on the ratio of
the cluster mass to the pressure in the surrounding interstellar medium. These
models explain why HII regions with low abundances have high excitation, and
demonstrate that at least part of the warm ionized medium is the result of
overlapping faint, old, large, and low pressure HII regions. We present line
ratios (at both optical and IR wavelengths) which provide reliable abundance
diagnostics for both single HII regions or for integrated galaxy spectra, and
we find a number that can be used to estimate the mean age of the cluster stars
exciting individual HII regions.Comment: 22 pages. 18 figures. Accepted for publication in Astrophysical
journal Supplements. Electronic tabular material is available on request to
[email protected]
Correlations and Characterization of Emitting Sources
Dynamical and thermal characterizations of excited nuclear systems produced
during the collisions between two heavy ions at intermediate incident energies
are presented by means of a review of experimental and theoretical work
performed in the last two decades. Intensity interferometry, applied to both
charged particles (light particles and intermediate mass fragments) and to
uncharged radiation (gamma rays and neutrons) has provided relevant information
about the space-time properties of nuclear reactions. The volume, lifetime,
density and relative chronology of particle emission from decaying nuclear
sources has been extensively explored and has provided valuable information
about the dynamics of heavy-ion collisions. Similar correlation techniques
applied to coincidences between light particles and complex fragments are also
presented as a tool to determine the internal excitation energy of excited
primary fragments as it appears in secondary-decay phenomena.Comment: To appear on Euorpean Physics Journal A as part of the Topical Volume
"Dynamics and Thermodynamics with Nuclear Degrees of Freedom
Long-term voluntary wheel running does not alter vascular amyloid burden but reduces neuroinflammation in the Tg-SwDI mouse model of cerebral amyloid angiopathy
Background: Cardiovascular exercise (CVE) has been shown to be protective against cognitive decline in aging and the risk for dementias, including Alzheimer’s Disease (AD). CVE has also been shown to have several beneficial effects on brain pathology and behavioral impairments in mouse models of AD; however, no studies have specifically examined the effects of CVE on cerebral amyloid angiopathy (CAA), which is the accumulation of amyloid-beta (Aβ) in the cerebral vasculature. CAA may be uniquely susceptible to beneficial effects of CVE interventions due to the location and nature of the pathology. Alternatively, CVE may exacerbate CAA pathology, due to added stress on already compromised cerebral vasculature.
Methods: In the current study, we examined the effects of CVE over many months in mice, thereby modeling a lifelong commitment to CVE in humans. We assessed this voluntary CVE in Tg-SwDI mice, a transgenic mouse model of CAA that exhibits behavioral deficits, fibrillar vascular Aβ pathology, and significant perivascular neuroinflammation. Various “doses” of exercise intervention (0 h (“Sedentary”), 1 h, 3 h, 12 h access to running wheel) were assessed from ~ 4 to 12 months of age for effects on physiology, behavior/cognitive performance, and pathology.
Results: The 12 h group performed the greatest volume of exercise, whereas the 1 h and 3 h groups showed high levels of exercise intensity, as defined by more frequent and longer duration running bouts. Tg-SwDI mice exhibited significant cerebral vascular Aβ pathology and increased expression of pro-inflammatory cytokines as compared to WT controls. Tg-SwDI mice did not show motor dysfunction or altered levels of anxiety or sociability compared to WT controls, though Tg-SwDI animals did appear to exhibit a reduced tendency to explore novel environments. At all running levels, CAA pathology in Tg-SwDI mice was not significantly altered, but 12-h high-volume exercise showed increased insoluble Aβ burden. However, CVE attenuated the expression of pro-inflammatory cytokines TNF-α and IL-6 and was generally effective at enhancing motor function and reducing anxiety-like behavior in Tg-SwDI mice, though alterations in learning and memory tasks were varied.
Conclusions: Taken together, these results suggest that CAA can still develop regardless of a lifespan of substantial CVE, although downstream effects on neuroinflammation may be reduced and functional outcomes improved
The Effects of Volume Versus Intensity of Long-Term Voluntary Exercise on Physiology and Behavior in C57/Bl6 Mice
Cardiovascular exercise (CVE) is associated with healthy aging and reduced risk of disease in humans, with similar benefits seen in animals. Most rodent studies, however, have used shorter intervention periods of a few weeks to a few months, begging questions as to the effects of longer-term, or even life-long, exercise. Additionally, most animal studies have utilized a single exercise treatment group – usually unlimited running wheel access – resulting in large volumes of exercise that are not clinically relevant. It is therefore incumbent to determine the physiological and cognitive/behavioral effects of a range of exercise intensities and volumes over a long-term period that model a lifelong commitment to CVE. In the current study, C57/Bl6 mice remained sedentary or were allowed either 1, 3, or 12 h of access to a running wheel per day, 5 days/weeks, beginning at 3.5–4 months of age. Following an eight-month intervention period, animals underwent a battery of behavioral testing, then euthanized and blood and tissue were collected. Longer access to a running wheel resulted in greater volume and higher running speed, but more breaks in running. All exercise groups showed similarly reduced body weight, increased muscle mass, improved motor function on the rotarod, and reduced anxiety in the open field. While all exercise groups showed increased food intake, this was greatest in the 12 h group but did not differ between 1 h and 3 h mice. While exercise dose-dependently increased working memory performance in the y-maze, the 1 h and 12 h groups showed the largest changes in the mass of many organs, as well as alterations in several behaviors including social interaction, novel object recognition, and Barnes maze performance. These findings suggest that long-term exercise has widespread effects on physiology, behavior, and cognition, which vary by “dose” and measure, and that even relatively small amounts of daily exercise can provide benefits
d-alpha Correlation functions and collective motion in Xe+Au collisions at E/A=50 MeV
The interplay of the effects of geometry and collective motion on d-
correlation functions is investigated for central Xe+Au collisions at E/A=50
MeV. The data cannot be explained without collective motion, which could be
partly along the beam axis. A semi-quantitative description of the data can be
obtained using a Monte-Carlo model, where thermal emission is superimposed on
collective motion. Both the emission volume and the competition between the
thermal and collective motion influence significantly the shape of the
correlation function, motivating new strategies for extending intensity
interferometry studies to massive particles.Comment: Accepted for publication on Physics Letters
Transition from in-plane to out-of-plane azimuthal enhancement in Au+Au collisions
The incident energy at which the azimuthal distributions in semi-central
heavy ion collisions change from in-plane to out-of-plane enhancement, E_tran,
is studied as a function of mass of emitted particles, their transverse
momentum and centrality for Au+Au collisions. The analysis is performed in a
reference frame rotated with the sidewards flow angle, Theta_flow, relative to
the beam axis. A systematic decrease of E_tran as function of mass of the
reaction products, their transverse momentum and collision centrality is
evidenced. The predictions of a microscopic transport model (IQMD) are compared
with the experimental results.Comment: 32 pages, Latex, 22 eps figures, accepted for publication in Nucl.
Phys.
Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: II. Control of the \HII Region Parameters
We examine, from a theoretical viewpoint, how the physical parameters of HII
regions are controlled in both normal galaxies and in starburst environments.
These parameters are the HII region luminosity function, the time-dependent
size, the covering fraction of molecular clouds, the pressure in the ionized
gas and the ionization parameter. The factors which control them are the
initial mass function of the exciting stars, the cluster mass function, the
metallicity and the mean pressure in the surrounding interstellar medium. We
investigate the sensitivity of the H luminosity to the IMF, and find
that this can translate to more than a factor two variation in derived star
formation rates. The molecular cloud dissipation timescale is estimated from a
case study of M17 to be Myr for this object. Based upon HII luminosity
function fitting for nearby galaxies, we suggest that the \HII region cluster
mass function is fitted by a log-normal form peaking at .
The cluster mass function continues the stellar IMF to higher mass. The
pressure in the HII regions is controlled by the mechanical luminosity flux
from the central cluster. Since this is closely related to the ionizing photon
flux, we show that the ionization parameter is not a free variable, and that
the diffuse ionized medium may be composed of many large, faint and old HII
regions. Finally, we derive theoretical probability distributions for the
ionization parameter as a function of metallicity and compare these to those
derived for SDSS galaxies.Comment: 36 pages, 8 figures. To be published in Astrophysical Journal, August
200
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