bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cost-effectiveness of Metered-Dose Inhalers for Asthma Exacerbations in the Pediatric Emergency Department
Authors: Doan Quynh , Shefrin Allan , Johnson David 
Published: April 2011

OBJECTIVE:
To compare the incremental cost and effects (averted admission) of using a metered-dose inhaler (MDI) against wet nebulization to deliver bronchodilators for the treatment of mild to moderately severe asthma in pediatric emergency departments (EDs).

METHODS:
We measured the incremental cost-effectiveness from the perspective of the hospital, by creating a model using outcome characteristics from a Cochrane systematic review comparing the efficacy of using MDIs versus nebulizers for the delivery of albuterol to children presenting to the ED with asthma. Cost data were obtained from hospitals and regional authorities. We determined the incremental cost-effectiveness ratio and performed probabilistic sensitivity analyses using Monte Carlo simulations.

RESULTS:
Using MDIs in the ED instead of wet nebulization may result in net savings of Can$154.95 per patient. Our model revealed that using MDIs in the ED is a dominant strategy, one that is more effective and less costly than wet nebulization. Probabilistic sensitivity analyses revealed that 98% of the 10 000 iterations resulted in a negative incremental cost-effectiveness ratio.
Sensitivity analyses around the costs revealed that MDI would remain a dominant strategy (90% of 10 000 iterations) even if the net cost of delivering bronchodilators by MDI was Can$70 more expensive than that of nebulized bronchodilators.

CONCLUSIONS:
Use of MDIs with spacers in place of wet nebulizers to deliver albuterol to treat children with mild-to-moderate asthma exacerbations in the ED could yield significant cost savings for hospitals and, by extension, to both the health care system and families of children with asthma.
A Systematic Review of Early Intensive Intervention for Autism Spectrum Disorders
Authors: Warren Zachary , McPheeters Melissa L. , Sathe Nila , Foss-Feig Jennifer H. , Glasser Allison , Veenstra-VanderWeele Jeremy 
Published: April 2011

CONTEXT:Early intensive behavioral and developmental interventions for young children with autism spectrum disorders (ASDs) may enhance developmental outcomes.OBJECTIVE:To systematically review evidence regarding such interventions for children aged 12 and younger with ASDs.METHODS:We searched Medline, PsycINFO, and ERIC (Education Resources Information Center) from 2000 to May 2010. Two reviewers independently assessed studies against predetermined inclusion/exclusion criteria. Two reviewers independently extracted data regarding participant and intervention characteristics, assessment techniques, and outcomes and assigned overall quality and strength-of-evidence ratings using predetermined criteria.RESULTS:Thirty-four unique studies met inclusion criteria. Seventeen studies were case series; 2 were randomized controlled trials. We rated 1 study as good quality, 10 as fair quality, and 23 as poor quality. The strength of the evidence overall ranged from insufficient to low. Studies of University of California Los Angeles/Lovaas–based interventions and variants reported clinically significant gains in language and cognitive skills in some children, as did 1 randomized controlled trial of an early intensive developmental intervention approach (the Early Start Denver Model). Specific parent-training approaches yielded gains in short-term language function and some challenging behaviors. Data suggest that subgroups of children displayed more prominent gains across studies, but participant characteristics associated with greater gains are not well understood.CONCLUSIONS:Studies of Lovaas-based approaches and early intensive behavioral intervention variants and the Early Start Denver Model resulted in some improvements in cognitive performance, language skills, and adaptive behavior skills in some young children with ASDs, although the literature is limited by methodologic concerns.
A Systematic Review of Secretin for Children With Autism Spectrum Disorders
Authors: Krishnaswami Shanthi , McPheeters Melissa L. , Veenstra-VanderWeele Jeremy 
Published: April 2011

CONTEXT:
As many as 1 in every 110 children in the United States has an autism spectrum disorder (ASD). Secretin is 1 of many medical treatments studied for treating the symptoms of ASDs, but there is currently no consensus regarding which interventions are most effective.

OBJECTIVE:
To systematically review evidence regarding the use of secretin in children with ASDs who are aged 12 years and younger.

METHODS:
We searched the Medline, PsycINFO, and ERIC (Education Resources Information Center) databases from 2000 to May 2010 and reference lists of included articles. Two reviewers independently assessed each study against predetermined inclusion/exclusion criteria. Two reviewers independently extracted data regarding participant and intervention characteristics, assessment techniques, and outcomes and assigned overall quality and strength-of-evidence ratings on the basis of predetermined criteria.

RESULTS:
Evidence from 7 randomized controlled trials supports a lack of effectiveness of secretin for the treatment of ASD symptoms including language and communication impairment, symptom severity, and cognitive and social skill deficits. No studies have resulted in significantly greater improvements in measures of language, cognition, or autistic symptoms when compared with placebo; study authors who reported improvement over time did so equally for both the intervention and placebo groups.

CONCLUSIONS:
Secretin has been studied extensively in multiple randomized controlled trials, and there is clear evidence that it lacks benefit. The studies of secretin included in this review uniformly point to a lack of significant impact of secretin in the treatment of ASD symptoms. Given the high strength of evidence for a lack of effectiveness, secretin as a treatment approach for ASDs warrants no further study.
Covalently interconnected and separated vanadosilicate shells
Authors: Wang Xiqu , Liu Lumei , Jacobson Allan J. 
Published: April 2011

ABSTRACTFour new compounds containing vanadosilicate clusters have been synthesized by hydrothermal reactions. The clusters are derived from the [V18O42] Keggin cluster by substitution of V=O caps by Si2O(O,OH)2 species. In Cs9[(V15Si6O46(OH)2Cl)(V2O4)](H2O)6.2, 1, the [V15Si6O46(OH)2] cluster shells are covalently interconnected by VO4 tetrahedra to form an infinite layer. In ((CH3)4N)4[V15Si6O42(OH)6(H2O)](H2O)20, 2, and ((CH3)4N)4(V(H2O)6)2/3 [V15Si6O42(OH)6 (H2O)](H2O), 3, separated [V15Si6O42(OH)6] cluster shells are interlinked by hydrogen bonds to form frameworks with wide channel systems. The separated cluster shell in ((CH3)4N)4((CH3)2NH2)((CH3)2NH) [V14Si8O42(OH)8(HCO2)] (H2O)4.7, 4, has four Si2O(OH)2 species in a tetrahedral configuration. The 2D structure of 1 and 0D structures of 2-4 complement the known 1D and 3D structures formed from such vanadosilicate shells.
The experimental determination of the onset of electrical and thermal conductivity percolation thresholds in carbon nanotube-polymer composites
Authors: Kim Byung-wook , Pfeifer Steven , Park Sung-Hoon , Bandaru Prabhakar R. 
Published: April 2011

ABSTRACTWe show evidence of electrical and thermal conductivity percolation in polymer based carbon nanotube (CNT) composites, which follow power law variations with respect to the CNT concentrations in the matrix. The experimentally obtained percolation thresholds, i.e., ~ 0.074 vol % for single walled CNTs and ~ 2.0 vol % for multi-walled CNTs, were found to be aspect ratio dependent and in accordance with those determined theoretically from excluded volume percolation theory. A much greater enhancement, over 10 orders of magnitude, was obtained in the electrical conductivity at the percolation threshold, while a smaller increase of ~ 100 % was obtained in the thermal conductivity values. Such a difference is qualitatively explained on the basis of the respective conductivity contrast between the CNT filler and the polymer matrix.
Nucleation of the electroactive phase of poly(vinylidene fluoride) by ferrite nanoparticles: surface versus size effects
Authors: Martins P. , Costa C. M. , Benelmekki M. , Lanceros-Mendez S. 
Published: April 2011

ABSTRACTMultiferroics and magnetoelectric materials show interesting scientific challenges and technnologial applications in sensors, acuators and data storage. In view of the fact that only a small number of materials show this kind of properties, exhaustive research activity is being pursued towards the development of new composite materials. Multiferroic nanocomposites films composed of piezoelectric poly(vinylidene fluoride) (PVDF) and magnetostrictive nanosize CoFe2O4, NiFe2O4 or NiZnFe2O4 ferrites were prepared by a solution method. Those ferrite nanoparticles have the ability to nucleate the electroactive β-phase of the polymer, providing in this way an easy route for the preparation of magnetoelectric particulate composites. The fact that the different nanoparticles promotes different amount of β-phase nucleation for different concentrations of nanoparticles indicates that filler size is not the most important parameter determining phase nucleation but the filler-matrix surface interaction. Further, when the polymer-ferrite surface interaction is modified through surfactation, the electroactive phase is not nucleated.
Self-Assembly of a Water-Soluble Tricyclic Heterocycle into J-Type Rosette Nanotubes
Authors: Borzsonyi Gabor , Beingessner Rachel L. , Yamazaki Takeshi , Cho Jae-Young , Myles Andrew J. , Kovalenko Andriy , Fenniri Hicham 
Published: April 2011

ABSTRACTThe synthesis and self-assembly of a water-soluble, tricyclic, self-complementary heterocycle that features the hydrogen bond donor-acceptor arrays of both guanine (G) and cytosine (C) juxtaposed between a pyridine ring is presented. In solution, this tricycle, which has been termed xK1, self-assembles into Rosette Nanotubes (RNTs) that have an inner diameter of 1.4 nm. Unlike the RNTs formed from the bicyclic congener K1, we demonstrate that xK1 with its extended ð system, forms a J-type RNT assembly determined through UV-Vis, CD and fluorescence spectroscopy experiments. This observation brings the possibility of developing electrically conducting RNTs for applications in the areas of photovoltaics and molecular wires.
Nano Patterning on Surfaces of 3-D Micro Structures by Means of Block Copolymer Self Assembly
Authors: Warisawa Shin’ichi , Mino Hiroyuki , Kometani Reo , Ishihara Sunao 
Published: April 2011

ABSTRACTIn this paper, we present the possibility of nano-scale patterning on surfaces of 3-D micro structures by means of block copolymer self assembly. We succeeded in forming vertical cylinders on the surfaces of the 3-D micro structures using dip-coat process with Au deposition instead of random copolymers. The material of 3-D structures fabricated by FIB-CVD was diamond-like carbon (DLC) due to selecting phenanthrene as a gas source. Since the surface energy of DLC is low, instead of PS-r-PMMA polymer brush, 100 nm-thick Au films were coated on the surfaces of 3-D structures. PS-b-PMMA (PS:PMMA = 50 kg/mol:21 kg/mol) was dip-coated on the Au coated surfaces and annealed. First, we prepared DLC 60° angled slope with size of 2.5 by 3 μm2. As a result, the vertical cylinders were formed in a similar way regardless of the places, i.e., top, middle and bottom on the slopes. vertical cylinders were formed regularly and densely on the entire slope. In order to investigate the effect of slope angle, we prepared 3-D micro structures with different angled slopes such as 70, 80 and 90°. There was no slope angle specific difference, and vertical cylinders were also formed on each slope.
Controlled Hydrothermal Synthesis of Complex Mixed Oxides Using Solution Redox Chemistry
Authors: Walton Richard I. , Sardar Kripasindhu , Playford Helen Y. , Modeshia Deena R. , Darton Richard J. , Fisher Janet , Thompsett David 
Published: April 2011

ABSTRACTWe present the results of a study of the solvothermal synthesis of mixed-metal cerium-containing oxides all prepared from CeCl3.7H2O at less than 250 ºC in single step reactions. The use of NaBiO3 in the presence of aqueous NaOH yields fluorite solid solutions Ce1-xBixO2-x/2 (x ≤ 0.6), whereas the use of either H2O2 or NaBrO3 as oxidant in the presence of TiF3 yields a Ce(IV) pyrochlore (Na0.33Ce0.67)2Ti2O7. With replacement of a fraction of the Ti reagent by Sn(IV) acetate, tin doping is possible in the pyrochlore. The materials have all been assessed for their use in catalysis by performing temperature programmed reduction (TPR) experiments under dilute hydrogen flow. The cerium-bismuth oxides show large and apparently reversible hydrogen uptake, but in situ powder X-ray diffraction shows that this is accompanied by phase separation into bismuth metal and CeO2 that occurs over 5 or more TPR cycles. In contrast, the cerium (IV) titanate pyrochlore shows reversible reduction at low temperature (150 ºC, after an activation step), which gives the material potential use as a precious metal support for catalysis: such as in the water-gas-shift reaction. Although Sn doping lowers the onset of reduction of the pyrochlore, consistent with an expanded lattice, the materials suffer from collapse to give SnO.
DLC-coated Substrate for Infrared Absorption Spectroscopy in Supercritical Water
Authors: Ube Takuji , Ishiguro Takashi 
Published: April 2011

ABSTRACTThe stability of several kinds of substrates, such as Corning #1737 glass, fused silica, synthetic silica, water free synthetic silica, zinc selenide, silicon, and diamond like carbon (DLC) coated Si in supercritical water (663K and 25MPa) were examined. Their reaction with the water was evaluated by using Fourier transform infrared (FT-IR) spectroscopy. As a result of the present experiment, it was found that DLC-coated Si is one of the most stable and useful substrates for IR spectroscopy in supercritical water.
Microstructural and Mechanical Properties of Polyester/Nanoclay Nanocomposites: Microstructure-Mixing Strategy Correlation
Authors: Dalir Hamid , Farahani Rouhollah D. , Nhim Vireya , Samson Benjamin , Lévesque Martin , Therriault Daniel 
Published: April 2011

ABSTRACTDifferent nanoclay mixing strategies using a three-roll mill and ultrasonication is proposed to obtain the desired polyester/nanoclay dispersion, intercalation, and exfoliation. The dispersion states of the modified nanoclay in polymer with 2, 4 and 6 wt% loading were characterized with X-ray diffraction, scanning electron microscopy (SEM), and low and high magnification transmission electron microscopy (TEM). The mechanical properties of the clay-reinforced polyester nanocomposites were a function of the nature and the content of the clay in the matrix. The nanocomposite containing 4 wt% modified Cloisite® 15A exhibits excellent improvement in modulus (by ~51%) and tensile strength (by ~12%) with a decrease in fracture strain (by ~26%) and fracture energy (by ~17%). These mechanical characteristic changes can be attributed to the dispersion, intercalation, and exfoliation of the nanoclays inside the polyester matrix.
Supercapacitor Based on Graphene – Polyaniline Nanocomposite Electrode
Authors: Gomez Humberto , Alvi Farah , Villalba Pedro , Ram Manoj. K. , Kumar Ashok 
Published: April 2011

ABSTRACTThis paper aims to investigate the concept of high power density and wider voltage window supercapacitors based on graphene-conducting polymer electrodes. The high conductivity, wider tunable potential window, stability of the electrode material in the doped form, faster charge transfer rate, and short charging times in graphene (G)-polyaniline (PANI) systems, contribute to the design and fabrication of high performance supercapacitors. Novel chemistries were used to synthesize a higher electronic conducting nanocomposite material based on graphene and polyaniline. The G-PANI nanocomposites were characterized, where an interesting structure was observed using different ratios of graphene with the aniline monomer. The G-PANI nanocomposite materials has shown the specific capacitance of 300 to 500 F/g at a current density of 0.1A/g. Based on the present experimental findings, it could be conclude that the G-PANI polymer nanocomposite supercapacitor technology could be transformative, and could surpass the existing technologies when the present synthesized novel material approach will be taken.
In-situ XRD and FIB microscopy studies of the dynamics of intermetallic phase formation in thin layer Cu/Sn films for low-temperature isothermal diffusion soldering
Authors: Etschmaier Harald , Novák Jiří , Eder Hannes , Hadley Peter 
Published: April 2011

ABSTRACTIn this contribution we report on the dynamics of the phase evolution in electrochemically deposited Sn thin films on copper coated substrates studied by in-situ X-ray diffraction (XRD) and Focused Ion Beam Microscopy (FIB). The data obtained is used to extract fundamental parameters such as the activation energy and the rate constant of the reaction. Results indicate that the formation of intermetallic phases in these thin layers, in which the grain size exceeds the layer thickness, is not limited by diffusion but rather by reaction kinetics.
Enhanced response characteristics of SnO2 thin film loaded with nanoscale catalytic clusters for Methane gas
Authors: Haridas Divya , Chowdhuri Arijit , Sreenivas K. , Gupta Vinay 
Published: April 2011

ABSTRACTIn recent years, an increase in usage of methane gas in household and automobile industry has been observed. Detection of methane is always a great cause of concern for safety at home or automobile industries, productions in mines and chemical factories. This paper reports the response characteristics of rf-sputtered SnO2 thin films (90 nm thin) loaded with nanoscale catalytic clusters for detection of methane. Ultrathin (8 nm) metal and metal-oxide catalysts (Pt, Ag, Ni, Pd, Au, NiO, Au2O3) clusters are loaded over the surface SnO2 thin film. The SnO2-Pd cluster structure is found to exhibit an enhanced response (97.2%) for 200 ppm of methane at a relatively low operating temperature (220oC). The enhanced response is shown to be primarily due to the dominant roles played by both Fermi level energy control mechanism and spillover mechanism.
Near white light emission from ZnO nanostructures
Authors: Brahma Sanjaya , Jaiswal P. , Nanda K. K. , Kukreja L. M. , Shivashankar S.A. 
Published: April 2011

ABSTRACTWe report white light emission from ZnO nanostructures in powder form, prepared by microwave irradiation-assisted chemical synthesis, in the presence of a structure directing agent. Determination of their crystallinity, actual shape, and orientation was made using X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and optical properties have been studied through photoluminescence (PL), measured using He-Cd laser (325 nm) as the excitation source. There is a noticeable variation in the luminescence correlated with variation of process parameters, such as microwave power, duration of irradiation, and the type/concentration of surfactants. The CIE (Commission Internationale l’Eclairage) diagram shows that the luminescence lies in yellow region of the color space. As the luminescence from the powder of ZnO lies in the yellow region, it is possible to produce white light from the powder of ZnO by using a blue laser as the excitation source.
Fabrication of Photovoltaic Devices using Novel Organic Polymer/Nanostructure Blends
Authors: Black David , Salaoru Iulia , Paul Shashi 
Published: April 2011

ABSTRACTOrganic photovoltaic devices offer a potentially cheap source of electrical power due to the relative ease of processing compared to silicon devices. Over the last decade the efficiency of these devices has improved significantly and the best devices are currently have >6% power conversion efficiency and ~100% quantum efficiency.A novel blend of ferroelectric nanostructures, poly(3-hexylthiophene) (P3HT) and [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM) has been used to fabricate hybrid organic and inorganic photovoltaic devices. These devices comprise a glass substrate coated with indium tin oxide (ITO) and an layer of PEDOT:PSS to form the first electrode. The active layer was deposited by spin coating and finally metallic top contacts have been added by thermal evaporation. The devices were characterized using standard current-voltage (IV) measurements under illuminated and dark conditions using an AM1.5 solar simulator and a source-voltage device and the results indicate a difference in efficiency compared to similar devices fabricated at the same time without the novel nanostructures. Additional UV-Vis measurements were used to determine the absorption characteristics of the active layers. The initial results suggest an improvement in the absorption of light in the visible region and higher open circuit voltages and short circuit currents compared to P3HT/PCBM alone.
Use of doped-YAG nanoparticles as down-converters for Photovoltaics
Authors: Raccurt Olivier , de Borniol Mervyn , Le Blevennec Gilles , Gerritsen Eric , Thony Philippe , Tebby Zoe 
Published: April 2011

ABSTRACTIncreasing solar cell efficiency by using spectral conversion is addressed in this article. To that purpose rare-earth doped YAG nanoparticles exhibiting down-conversion and quantum cutting properties have been prepared. These nanoparticles have been synthesized with different concentrations of dopants in order to optimize the luminescence and the quantum cutting efficiency. Results on the incorporation of selected material into the encapsulating layer of c-Si based PV-modules are also presented. The effect of down-conversion has been demonstrated through the increase of photocurrent of encapsulated silicon solar cells.
pO2 stability of Ba0.5Sr0.5Co0.8Fe0.2O3-δ
Authors: Wagner Stefan F. , Taufall Simon , Niedrig Christian , Götz Holger , Menesklou Wolfgang , Baumann Stefan , Ivers-Tiffée Ellen 
Published: April 2011

ABSTRACTThe mixed-conducting perovskite oxide Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), given its outstanding oxygen ionic and electronic transport properties, is considered a promising material composition for oxygen transport membranes (OTM) operated at high temperatures.Its long-term stability under operating conditions is, however, still an important issue. Although the incompatibility of BSCF with CO2-containing atmospheres can be avoided by appropriate means (oxyfuel processes in the absence of carbon dioxide), the thermal as well as the chemical stability of BSCF itself are still under thorough investigation.This work is focused on the stability of BSCF in the targeted temperature range for OTM applications (700…900 °C) and in atmospheres with low oxygen contents. Previous studies in literature suggest limited chemical stability below oxygen partial pressures pO2 of around 10-6 bar.By using a coulometric titration method based on a zirconia “oxygen pump” setup, precise control of the oxygen partial pressure pO2 between 1 bar and 10-18 bar was facilitated. Combining electrical measurements on dense ceramic bulk samples performed as a function of pO2 with an XRD phase composition study of single phase BSCF powders subjected to various pO2 treatments, an assessment of the chemical stability of BSCF is facilitated as a function of oxygen partial pressure. It could thus be shown that the pO2 stability limit is considerably lower than previously assumed in literature.