127 research outputs found
Convenience Over Nutrition for Recreation League Youth Sport Team Snack and Mealtime Choices
Fifty-six percent of school-aged children participate in team sports, yet there is limited evidence on how participation in youth sports impacts the dietary behaviors of participants and their families. Our team surveyed parents and caregivers of children participating in recreation league youth sports (n = 178) to assess the foods and beverages offered as team snacks and factors that influence team snack choices. Juice was the most popular beverage, and crackers were the most popular snack reported by parents. Convenience, followed by cost and child preference, were the most frequently reported factors influencing team snack choices. Survey items also included factors that influence mealtime behaviors on game and practice days. Convenience, followed by nutrition and taste, were most frequently reported as factors that influenced mealtime behaviors. Almost half of parents said their family’s eating habits changed as a result of recreational youth sports activities, and more than half said their family often or always eats dinner outside of the home on game and practice days. Professionals who work with this age group and their parents, including extension agents, can tailor education to encourage healthy team snacks and promote strategies to make healthy meals accessible on evenings with youth sports
Markov, fractal, diffusion, and related models of ion channel gating. A comparison with experimental data from two ion channels
The gating kinetics of single-ion channels are generally modeled in terms of Markov processes with relatively small numbers of channel states. More recently, fractal (Liebovitch et al. 1987. Math. Biosci. 84:37–68) and diffusion (Millhauser et al. 1988. Proc. Natl. Acad. Sci. USA. 85:1502–1507) models of channel gating have been proposed. These models propose the existence of many similar conformational substrates of the channel protein, all of which contribute to the observed gating kinetics. It is important to determine whether or not Markov models provide the most accurate description of channel kinetics if progress is to be made in understanding the molecular events of channel gating. In this study six alternative classes of gating model are tested against experimental single-channel data. The single-channel data employed are from (a) delayed rectifier K+ channels of NG 108–15 cells and (b) locust muscle glutamate receptor channels. The models tested are (a) Markov, (b) fractal, (c) one-dimensional diffusion, (d) three-dimensional diffusion, (e) stretched exponential, and (f) expo-exponential. The models are compared by fitting the predicted distributions of channel open and closed times to those observed experimentally. The models are ranked in order of goodness-of-fit using a boot-strap resampling procedure. The results suggest that Markov models provide a markedly better description of the observed open and closed time distributions for both types of channel. This provides justification for the continued use of Markov models to explore channel gating mechanisms
Discrete Symmetries and Generalized Fields of Dyons
We have studied the different symmetric properties of the generalized
Maxwell's - Dirac equation along with their quantum properties. Applying the
parity (\mathcal{P}), time reversal (\mathcal{T}), charge conjugation
(\mathcal{C}) and their combined effect like parity time reversal
(\mathcal{PT}), charge conjugation and parity (\mathcal{CP}) and \mathcal{CP}T
transformations to varius equations of generalized fields of dyons, it is shown
that the corresponding dynamical quantities and equations of dyons are
invariant under these discrete symmetries.
Abstract Key words- parity, time reversal, charge-conjugation, dyons
Abstract PACS No.- 14.80 Hv
Mucus accumulation in the lungs precedes structural changes and infection in children with cystic fibrosis
Although destructive airway disease is evident in young children with cystic fibrosis (CF), little is known about the nature of the early CF lung environment triggering the disease. To elucidate early CF pulmonary pathophysiology, we performed mucus, inflammation, metabolomic, and microbiome analyses on bronchoalveolar lavage fluid (BALF) from 46 preschool children with CF enrolled in the Australian Respiratory Early Surveillance Team for Cystic Fibrosis (AREST CF) program and 16 non-CF disease controls. Total airway mucins were elevated in CF compared to non-CF BALF irrespective of infection, and higher densities of mucus flakes containing mucin 5B and mucin 5AC were observed in samples from CF patients. Total mucins and mucus flakes correlated with inflammation, hypoxia, and oxidative stress. Many CF BALFs appeared sterile by culture and molecular analyses, whereas other samples exhibiting bacterial taxa associated with the oral cavity. Children without computed tomography–defined structural lung disease exhibited elevated BALF mucus flakes and neutrophils, but little/no bacterial infection. Although CF mucus flakes appeared “permanent” because they did not dissolve in dilute BALF matrix, they could be solubi-lized by a previously unidentified reducing agent (P2062), but not N-acetylcysteine or deoxyribonuclease. These findings indicate that early CF lung disease is characterized by an increased mucus burden and inflammatory markers without infection or structural lung disease and suggest that mucolytic and anti-inflammatory agents should be explored as preventive therapy
Prominence seismology using small amplitude oscillations
Quiescent prominences are thin slabs of cold, dense plasma embedded in the
much hotter and rarer solar corona. Although their global shape is rather
irregular, they are often characterised by an internal structure consisting of
a large number of thin, parallel threads piled together. Prominences often
display periodic disturbances mostly observed in the Doppler displacement of
spectral lines and with an amplitude typically of the order of or smaller than
2--3 km s, a value which seems to be much smaller than the
characteristic speeds of the prominence plasma (namely the Alfv\'en and sound
velocities). Two particular features of these small amplitude prominence
oscillations is that they seem to damp in a few periods and that they seem not
to affect the whole prominence structure. In addition, in high spatial
resolution observations, in which threads can be discerned, small amplitude
oscillations appear to be clearly associated to these fine structure
constituents. Prominence seismology tries to bring together the results from
these observations (e.g. periods, wavelengths, damping times) and their
theoretical modeling (by means of the magnetohydrodynamic theory) to gain
insight into physical properties of prominences that cannot be derived from
direct observation. In this paper we discuss works that have not been described
in previous reviews, namely the first seismological application to solar
prominences and theoretical advances on the attenuation of prominence
oscillations
The origins and development of Zuwīla, Libyan Sahara: an archaeological and historical overview of an ancient oasis town and caravan centre
Zuwīla in southwestern Libya (Fazzān) was one of the most important early Islamic centres in the Central Sahara, but the archaeological correlates of the written sources for it have been little explored. This paper brings together for the first time a detailed consideration of the relevant historical and archaeological data, together with new AMS radiocarbon dates from several key monuments. The origins of the settlement at Zuwīla were pre-Islamic, but the town gained greater prominence in the early centuries of Arab rule of the Maghrib, culminating with the establishment of an Ibāḍī state ruled by the dynasty of the Banū Khaṭṭāb, with Zuwīla its capital. The historical sources and the accounts of early European travellers are discussed and archaeological work at Zuwīla is described (including the new radiocarbon dates). A short gazetteer of archaeological monuments is provided as an appendix. Comparisons and contrasts are also drawn between Zuwīla and other oases of the ash-Sharqiyāt region of Fazzān. The final section of the paper presents a series of models based on the available evidence, tracing the evolution and decline of this remarkable site
Search for the lepton flavor violating decay A^0/H^0 --> tau^{+/-} mu^{+/-} at hadron colliders
In the two Higgs doublet model type III and in several other extensions of
the Standard Model, there are no discrete symmetries that suppress flavor
changing couplings at tree level. The experimental observation of the nu_mu --
nu_tau flavor oscillation may suggest the non-conservation of lepton number.
This would lead to the decay of the type A^0/H^0 --> tau^{+/-} mu^{+/-}. We
determine the present low energy limit on lepton flavor violating (LFV)
couplings from the muon g-2 measurement and discuss the prospects for detecting
lepton flavor violating decays at the TeVatron and at the Large Hadron
Collider. The achievable bounds on the LFV coupling parameter lambda_{tau mu}
are presented.Comment: 19 pages, 21 figures. Updated version takes into account the recent
results on the muon g-2 measurements. Submitted to Phys. Rev. D. Added minor
corrections from a refere
The Origin, Early Evolution and Predictability of Solar Eruptions
Coronal mass ejections (CMEs) were discovered in the early 1970s when space-borne coronagraphs revealed that eruptions of plasma are ejected from the Sun. Today, it is known that the Sun produces eruptive flares, filament eruptions, coronal mass ejections and failed eruptions; all thought to be due to a release of energy stored in the coronal magnetic field during its drastic reconfiguration. This review discusses the observations and physical mechanisms behind this eruptive activity, with a view to making an assessment of the current capability of forecasting these events for space weather risk and impact mitigation. Whilst a wealth of observations exist, and detailed models have been developed, there still exists a need to draw these approaches together. In particular more realistic models are encouraged in order to asses the full range of complexity of the solar atmosphere and the criteria for which an eruption is formed. From the observational side, a more detailed understanding of the role of photospheric flows and reconnection is needed in order to identify the evolutionary path that ultimately means a magnetic structure will erupt
Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4
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