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Introduction: Gastroenteritis accounts for 1.7 million emergency department visits by children annually in the United States. We conducted a double-blind trial to determine whether twice daily probiotic administration for 5 days, improves outcomes. Methods: 886 children aged 348 months with gastroenteritis were enrolled in six Canadian pediatric emergency departments. Participants were randomly assigned to twice daily Lactobacillus rhamnosus R0011 and Lactobacillus helveticus R0052, 4.0 x 109 CFU, in a 95:5 ratio or placebo. Primary outcome was development of moderate-severe disease within 14 days of randomization defined by a Modified Vesikari Scale score 9. Secondary outcomes included duration of diarrhea and vomiting, subsequent physician visits and adverse events. Results: Moderate-severe disease occurred in 108 (26.1%) participants administered probiotics and 102 (24.7%) participants allocated to placebo (OR 1.06; 95%CI: 0.77, 1.46; P=0.72). After adjustment for site, age, and frequency of vomiting and diarrhea, treatment assignment did not predict moderate-severe disease (OR, 1.11, 95%CI, 0.80 to 1.56; P=0.53). In the probiotic versus placebo groups, there were no differences in the median duration of diarrhea [52.5 (18.3, 95.8) vs. 55.5 (20.2, 102.3) hours; P=0.31], vomiting [17.7 (0, 58.6) vs. 18.7 (0, 51.6) hours; P=0.18], physician visits (30.2% vs. 26.6%; OR 1.19; 95% CI0.87. 1.62; P=0.27), or adverse events (32.9% vs. 36.8%; OR 0.83; 95%CI 0.62. 1.11; P=0.21). Conclusion: In children presenting to an emergency department with gastroenteritis, twice daily administration of 4.0 x 109 CFU of a Lactobacillus rhamnosus/helveticus probiotic does not prevent development of moderate-severe disease or improvements in other outcomes measured.
This paper presents the results of investigations at the ancient Maya site of Margarita in south-central Quintana Roo, Mexico, and relates them to documented patterns at neighboring centers. Following initial settlement of the region in the Middle Preclassic, settlement hierarchies topped by large centers with monumental architecture, carved monuments, and associations with sites to the south emerged in the Late Preclassic to Early Classic periods. In the Late Classic, several primary centers declined and there was a proliferation of affluent urban populations—evidenced by construction of elaborate residential groups—at smaller centers like Margarita. Long-distance cultural affiliations shifted as well, with ceramic and architectural links to western and northern Yucatán becoming pronounced. Many settlements were abandoned in the Terminal Classic, but there is also evidence of the formation of “post-collapse” communities at Margarita and other neighboring sites during the same period.
This article provides a basic report about subject recruitment processes for Web-based surveys. Using data from our ongoing Internet Survey of American Opinion project, two different recruitment techniques (banner advertisement and subscription campaigns) are compared. This comparison, together with a typology of Web-based surveys, provides insight into the validity and generalizability of Internet survey data. The results from this analysis show that, although Internet survey respondents differ demographically from the American population, the relationships among variables are similar across recruitment methods and match those implied by substantive theory. Thus, our research documents the basic methodology of subject acquisition for Web-based surveys, which, as we argue in our conclusion, may soon become the survey interview mode of choice for social scientists.
To determine the prospective relationship between changes in sugar-sweetened beverage (SSB) intake and central adiposity in older children.
Dietary intakes of children were obtained by 3 d food records at ages 10 and 13 years. Waist circumference (WC) and weight and height to determine BMI were measured at 10 and 13 years and total body fat mass (TBFM) at 13 years by dual-energy X-ray absorptiometry. Analyses were conducted using multivariable linear regression. Reporting errors were measured and participants were categorized as under-, plausible and over-reporters of dietary intakes.
Community-based British cohort of children participating in the Avon Longitudinal Study of Parents and Children.
Among 2455 older children, increased SSB consumption from ages 10 to 13 years was associated with higher WC (standardized β=0·020, P=0·19), BMI (β=0·028, P=0·03) and TBFM (β=0·017, P=0·20) at 13 years. Effects were strengthened among plausible dietary reporters (n 1059): WC (β=0·097, P<0·001), BMI (β=0·074, P<0·001) and TBFM (β=0·065, P=0·003). The association between change in SSB and WC was weakened, but remained statistically significant after accounting for BMI (β=0·042, P=0·02) and TBFM (β=0·048, P=0·01).
Higher consumption of SSB from ages 10 to 13 years was associated with a larger WC at age 13 years independent of differences in total adiposity. Accounting for dietary reporting errors strengthened associations. Our findings further support recommendations to limit intakes of SSB to reduce excess weight gain in children and suggest that SSB have an additional deleterious effect on central adiposity.
Anomalously broad diffuse interstellar bands (DIBs) at 5780.5, 5797.1, 6196.0, and 6613.6 Å are found in absorption along the line of sight to Herschel 36, an O star system next to the bright Hourglass nebula of the Hii region Messier 8. Excited lines of CH and CH+ are seen as well. We show that the region is very compact and itemize other anomalies of the gas. An infrared-bright star within 400 AU is noted. The combination of these effects produces anomalous DIBs, interpreted by Oka et al. (2013, see also this volume) as being caused predominantly by infrared pumping of rotational levels of relatively small molecules.
Our colloidal system is composed of antigens covalently coupled to polystyrene microspheres. When monoclonal antibodies are added to solution, they reversibly bind to the antigens causing aggregation. Unlike many other similar systems, our system is thermodynamicallyreversible: the aggregates will dissociate in the presence of free antigen, and the aggregation process reaches a state of thermodynamic equilibrium. This system is of interest as it can be used to model many different chemical, physical and biological processes. In particular, this system can be used to quantify the interactions between the biomoleculesattached to the microspheres1 and also to explore the statistical mechanics of reversible particle aggregation.
In this report, we present a bio-inspired encapsulation process to create nanocluster-assembled core-shell particles under aqueous, room temperature and non-toxic conditions. The approach to synthesize calcium carbonate core-shell particles is accomplished by employing a Polymer-Induced Liquid-Precursor (PILP) process. We demonstrate the amorphous mineral precursor is coated around a core of hydrogel nanoparticles, and subsequently solidified and crystallized. The synthesized core-shell particles are 300∼500nm diameter and ∼100 nm shell-thickness. We investigate the role of the hydrogel core of the particle using time-resolved XRD, thermal-XRD and thermal analysis. The organic hydrogel appears to influence the transformation of mineral phases, stabilizing the amorphous phase of calcium carbonate.
We have developed analytic SPICE models for hydrogenated amorphous silicon (a-Si:H) and polysilicon (poly-Si) thin film transistors (TFTs) which accurately model all regimes of operation, are temperature dependent to 150°C, and scale with device dimensions. These models have been presented in [1, 2]. In this work, we compare the current-voltage characteristics predicted by our models with the measured characteristics from TFTs fabricated at different foundries. We compare the extracted device parameters in order to evaluate the robustness of our models and to determine a suitable default parameter set. We also use the models to examine the effects of device scaling for short channel TFTs. The models can be accessed using the circuit simulator AIM-Spice , which is available at http://nina.ecse.rpi.edu/aimspice.
We evaluated the characteristics of a-Si:H/a-SiNx:H thin film transistors (TFTs), and of separately deposited a-Si:H films, as functions of the a-Si:H deposition power in a high-rate, large-area, 40 MHz PE-CVD system. TFT performance and a-Si:H film properties improve with decreasing power density and deposition rate. However, low defect density a-Si:H material was deposited at rates as high as 1500 Å/min. TFTs with gate nitride deposited at 1000 A/min show excellent I-V characteristics when the a-Si:H deposition power is low enough. The TFT electron mobility in the linear regime correlates well with the Urbach energy of the a-Si:H films, suggesting that the quality of the a-Si: H controls the performance of our TFTs.
We report extensive optical and electronic transport data on silicon-implanted a-Si:H, annealed in steps in the dark or with additional illumination. All measured properties relax gradually with increasing annealing temperature. The dark conductivity of the as-implanted film is dominated by hopping conduction via midgap defects. This channel is pinched off during the initial stages of annealing. The midgap defect density and the Urbach energy follow an annealing path that agrees qualitatively with the trajectory postulated by the equilibrium theory of the dangling-bond density. Therefore, the silicon network and the defect density equilibrate continuously during network relaxation.
The results of structural and electrical characterizations of SrTiO3 thin films deposited onto LaAlO3 substrates by pulsed laser deposition technique are presented. The appearance of the ferroelectric phase in these films has been experimentally documented, the transition temperature being in the range of 90–120K. The hysteresis loops have been monitored in a wide temperature range by using thin film planar capacitors, the driving field being predominantly in the plane of the film. The switching properties of the films has been studied at low temperatures (∼25K) and well saturated loops have been observed with relatively low coercive field (<6kV/cm for 10μm gap). The presence of the imprint phenomenon has been also found at low temperatures.
The microstructure of the investigated SrTiO3 thin films has been studied by using a high resolution transmission electron microscope (TEM). It has been found that the annealed and as-deposited thin films, being of the same composition, have quite different microstructures. The difference observed in the polarization response of the films is related to that in their microstructure.
Recently, Sherman et al.  analyzed an M/G/1 retrial queuing model in which customers are forced to retry their service if interrupted by a server failure. Using classical techniques, they provided a stability analysis, queue length distributions, key performance parameters, and stochastic decomposition results. We analyze the system under a static Bernoulli routing policy that routes a proportion of arriving customers directly to the orbit when the server is busy or failed. In addition to providing the key performance parameters, we show that this system exhibits a dual stability structure, and we characterize the optimal Bernoulli routing policy that minimizes the total expected holding costs per unit time.
As a model for streaming multimedia applications, we study an unreliable retrial queue with infinite-capacity orbit and normal queue for which the retrial rate and the server repair rate are controllable. Customers join the retrial orbit if and only if their service is interrupted by a server failure. Interrupted customers do not rejoin the normal queue but repeatedly attempt to access the server at independent and identically distributed intervals until it is found functioning and idle. We provide stability conditions, queue length distributions, stochastic decomposition results, and performance measures. The joint optimization of the retrial and server repair rates is also studied.