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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.
Apathy, characterized by diminished motivation, is a highly prevalent neuropsychiatric symptom in dementia. However, there is a substantial knowledge gap with regard to prevalence rates, neurobiological underpinnings, and effective treatments for apathy in pre-dementia states, including mild cognitive impairment (MCI) and mild behavioral impairment (MBI).
We conducted a comprehensive literature search using MEDLINE, Embase, and PsycINFO databases to identify available research on apathy in prodromal dementia.
Apathy has consistently been detected in individuals with MCI with varying prevalence rates, and only recently has literature discussed the prevalence of apathy in MBI. Few pharmacological treatments have been utilized for apathy, with galantamine and risperidone showing mild reductions in apathetic behaviors. Non-pharmacological interventions in prodromal dementia are beginning to be explored and show promise, but few studies have replicated those results.
More comprehensive guidelines for diagnosing apathy and further research investigating neurobiological mechanisms of apathy in MCI and MBI are required in order to effectively treat apathetic patients in prodromal dementia.
The goals of these experiments were to describe the morphology and synaptic
connections of amacrine cells in the baboon retina that contain immunoreactive
vesicular glutamate transporter 3 (vGluT3). These amacrine cells had the
morphology characteristic of knotty bistratified type 1 cells, and their
dendrites formed two plexuses on either side of the center of the inner
plexiform layer. The primary dendrites received large synapses from amacrine
cells, and the higher-order dendrites were both pre- and postsynaptic to other
amacrine cells. Based on light microscopic immunolabeling results, these include
AII cells and starburst cells, but not the polyaxonal amacrine cells
tracer-coupled to ON parasol ganglion cells. The vGluT3 cells received input
from ON bipolar cells at ribbon synapses and made synapses onto OFF bipolar
cells, including the diffuse DB3a type. Many synapses from vGluT3 cells onto
retinal ganglion cells were observed in both plexuses. At synapses where vGluT3
cells were presynaptic, two types of postsynaptic densities were observed; there
were relatively thin ones characteristic of inhibitory synapses and relatively
thick ones characteristic of excitatory synapses. In the light microscopic
experiments with Neurobiotin-injected ganglion cells, vGluT3 cells made contacts
with midget and parasol ganglion cells, including both ON and OFF types. Puncta
containing immunoreactive gephyrin, an inhibitory synapse marker, were found at
appositions between vGluT3 cells and each of the four types of labeled ganglion
cells. The vGluT3 cells did not have detectable levels of immunoreactive
γ-aminobutyric acid (GABA) or immunoreactive glycine transporter 1.
Thus, the vGluT3 cells would be expected to have ON responses to light and make
synapses onto neurons in both the ON and the OFF pathways. Taken with previous
results, these findings suggest that vGluT3 cells release glycine at some of
their output synapses and glutamate at others.
In a cohort of government employees in Rio de Janeiro, Brazil, we investigated prospectively, sex-specific associations between education and BMI trajectories and their potential effect modification by race.
Of the 4030 participants in Phase 1 (1999), 3253 (81 %) participated in Phase 2 (2003) and 3058 (76 %) participated in Phase 3 (2006). Education was categorized as elementary, high school or college graduate. Study participants self-identified as White, Black or Pardo. BMI was calculated from measured weight and height. BMI trajectories were modelled using a generalized additive regression model with mixed effects (GAMM).
The Pro-Saúde Study, a longitudinal investigation of social determinants of health.
Women (n 1441) and men (n 1127) who participated in the three phases of data collection and had complete information for all study variables.
Women and men with less than high school, or only a high school education, gained approximately 1 kg/m2 more than college graduates (women: 1·06 kg/m2 (P<0·001) and 1·06 kg/m2 (P<0·001), respectively; men: 1·04 kg/m2 (P=0·013) and 1·01 kg/m2 (P=0·277), respectively). For women only, race was independently associated with weight gain. Women identifying as Pardo or Black gained 1·03 kg/m2 (P=0·01) and 1·02 kg/m2 (P=0·10), respectively, more than Whites. No effect modification by race was observed for either men or women.
While both lower education and darker race were associated with greater weight gain, gender similarities and differences were observed in these associations. The relationship between weight gain and different indicators of social status are therefore complex and require careful consideration when addressing the obesity epidemic.
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.
There have been fundamental changes in the intergenerational family, and yet families continue to be an important part of people's lives. We use the convoy model to describe the factors that influence supportive relations within intergenerational families, beginning with a description of the changing structure of the intergenerational family. We next outline support exchanges, detailing how personal characteristics, especially gender, race, age and socio-economic status, and situational characteristics, in particular family structure and intergenerational context, influence support exchanges. Instrumental and emotional family exchanges are described, with special attention to the unique circumstances of care-giving in intergenerational families. We also examine the importance of recognising differences in the quality of intergenerational relations, again noting the influence of personal and situational characteristics. Variations in support quality, e.g. positive, negative and ambivalent, and its influence on wellbeing are discussed. As families and individuals change, differences emerge at the individual, family and societal levels. We consider the implications of changes and stability in intergenerational relations and make recommendations about how best to envisage and plan future intergenerational family support. Societies with fewer resources as well as individuals and families with diverse individual histories must be innovative and creative in meeting the needs of older people as well as those of all family members.
Controlled precipitation conditions allow the formation of highly porous, spheroidal aggregates of hydrotalcite. The aggregate structure resembles a house-of-cards, being composed of interconnected thin plates. The aggregate size can vary over a range of about 1 to 60 μm by altering precipitation conditions such as mixing shear, temperature, addition rates and addition order. These materials are low in bulk density and highly absorptive. The aggregate structure is maintained during calcination. The micro and meso-pore size distribution is very similar to conventionally prepared hydrotalcite, but the macroporosity is dominated by the voids between spheroids. The characteristics of these aggregates point to potential applications in areas such as catalysis and separation.
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 i-layers of the middle and bottom cells in stable triple-junction amorphous silicon solar cells are composed of a-SiGe:H alloys which are graded in composition to enhance performance. We compare modeling and experimental results for three i-layer band gap grading schemes to determine the optimal profile. We find a good correlation between model trends and measured device parameters for all grading schemes. This is encouraging for the use of the model in predictive device design. We find that the highest white and red light performance do not necessarily have the same cell parameter set. Modeling and experiment indicate that thin cells without band gap profile and with suitably designed p/i and n/i buffer layers, have the best red light performance.
High deposition rates and good quality electrical properties and thickness uniformities over large areas are required for all three films (SiNx, a-Si:H and n+ a-Si:H) composing the thin film transistors (TFTs) for the AMLCD industry, while maintaining high tool up-time and low particle formation. Generally these conditions have been achieved for most single-panel multichamber PECVD systems; however, it has become increasingly apparent that a compromise is drawn between the TFT mobility and the deposition rate of the a-Si:H layer. Thus it becomes essential to clearly assess the industry requirements for both deposition rates as well as TFT performance for the different device structures used for AMLCDs, and to discover and control these underlying material properties.
The TEL VHF (40/60 MHz) PECVD system produces high quality, low defect density a- Si:H at deposition rates exceeding 1500 Å/min when analyzed by FTIR, CPM, photo and dark conductivity. Even though the low deposition rate a-Si:H exhibits very similar bulk properties, higher mobility TFTs are produced with a-Si:H deposited at lower RF power. Having both a high ion flux and low ion energy in the SiH4 discharge are likely the most critical conditions for controlling the a-Si:H quality and thus the TFT mobility. Increasing the RF frequency enhances both of these effects, as well as provides a higher deposition rate for a given power density and a higher power threshold for particle/powder formation. For these reasons it is likely a 40/60 MHz plasma will produce better performing TFTs for a given deposition rate when compared with a conventional 13.56 MHz system. Other process conditions such as diluting the SiH4 in H2 or Ar also seem to play an important role in the optoelectronic properties of the a-Si:H film and ultimately the TFT performance.
High deposition rates and good quality electrical properties and thickness uniformities over large areas are required for all three films (SiNx, a-Si:H and n+a-Si:H) composing the thin film transistors (TFTs) for the AMLCD industry, while maintaining high tool up-time and low particle formation. Generally these conditions have been achieved for most single-panel multichamber PECVD systems; however, it has become increasingly apparent that a compromise is drawn between the TFT mobility and the deposition rate of the a-Si:H layer. Thus it becomes essential to clearly assess the industry requirements for both deposition rates as well as TFT performance for the different device structures used for AMLCDs, and to discover and control these underlying material properties.
The TEL VHF (40/60 MHz) PECVD system produces high quality, low defect density a- Si:H at deposition rates exceeding 1500 Å/min when analyzed by FTIR, CPM, photo and dark conductivity. Even though the low deposition rate a-Si:H exhibits very similar bulk properties, higher mobility TFTs are produced with a-Si:H deposited at lower RF power. Having both a high ion flux and low ion energy in the SiH4 discharge are likely the most critical conditions for controlling the a-Si:H quality and thus the TFT mobility. Increasing the RF frequency enhances both of these effects, as well as provides a higher deposition rate for a given power density and a higher power threshold for particle/powder formation. For these reasons it is likely a 40/60 MHz plasma will produce better performing TFTs for a given deposition rate when compared with a conventional 13.56 MIHz system. Other process conditions such as diluting the SiH4 in H2 or Ar also seem to play an important role in the optoelectronic properties of the a-Si:H film and ultimately the TFT performance.