119 research outputs found
Comparing Traditional and Integrative Learning Methods in Organizational Training Programs
Previous research and anecdotal reports have suggested that when certain teaching approaches are utilized, students not only learn more, but also experience greater satisfaction with the training process. This study examined the effects of Integrative Learning-based (IL) training relative to lecture-based training. Employees enrolled in a three-day Manufacturing Resource Planning training course were randomly assigned to either IL or traditional training. Subjects reacted more favorably to IL-based training. Trained subjects performed significantly better than those in a no-treatment control group but no differences were noted between training interventions
Understanding the role of promoters in catalysis: operando XAFS/DRIFTS study of CeO<sub>x</sub>/Pt/Al<sub>2</sub>O<sub>3</sub> during CO oxidation
A combined operando XAFS/DRIFTS study on CeOx/Pt/Al2O3 catalysts has been performed during CO oxidation and provides insights into the changes in nanoparticle structure and adsorbed species during the reaction profile. The onset of CO2 formation is shown to be concurrent with a rapid re-oxidation of the Pt nanoparticles, evidenced by XAFS spectroscopy, and the loss of bridge bonded CO adsorbed on Pt, as shown by simultaneous DRIFTS acquisition. The continued appearance of linear bound CO on the catalyst surface is shown to remain long after catalytic light off. The interaction of Pt and CeOx is evidenced by the improved performance towards CO oxidation, compared to the non-CeOx modified Pt/Al2O3, and changes in the CO adsorption properties on Pt previously linked to Pt-CeO2 interfaces
Comparing traditional and integrative learning methods in organizational training programs.
Hydrostability and Scaling Up Molecular Sieve Silica (MSS) Membranes for H2/CO Separation in Fuel Cell Systems
MSS membranes are a good candidate for CO cleanup in fuel cell fuel processing systems due to their ability to selectively permeate H2 over CO via molecular sieving. Successfully scaled up tubular membranes were stable under dry conditions to 400°C with H2 permeance as high as 2 x 10-6 mol.m-2.s^-1.Pa^-1 at 200 degrees C and H2/CO selectivity up to 6.4, indicating molecular sieving was the dominant mechanism. A novel carbonised template molecular sieve silica (CTMSS) technology gave the scaled up membranes resilience in hydrothermal conditions up to 400 degrees C in 34% steam and synthetic reformate, which is required for use in fuel cell CO cleanup systems
On the effect of metal loading on the reducibility and redox chemistry of ceria supported Pd catalysts
The effect of Pd loading on the redox characteristics of a ceria support was examined using in situ Pd K-edge XAS, Ce L3-edge XAS and in situ X-ray diffraction techniques. Analysis of the data obtained from these techniques indicates that the onset temperature for the partial reduction of Ce(IV) to Ce(III), by exposure to H2, varies inversely with the loading of Pd. Whilst the onset and completion temperatures of the reduction of Ce(IV) to Ce(III) are different, both samples yield the same maximal fraction of Ce(III) formation independent of Pd loading. Furthermore, the partial reduction of Ce is found to be concurrent with the reduction of PdO and demonstrated that the presence of metallic Pd is necessary for the reduction of the CeO2 support. Upon passivation by room temperature oxidation, a full oxidation of the reduced ceria support was observed. However, only a mild surface oxidation of Pd was identified. The mild passivation of the Pd is found to lead to a highly reactive sample upon a second reduction by H2. The onset of the reduction of Pd and Ce has been demonstrated to be independent of the Pd loading after a mild passivation with both samples exhibiting near room temperature reduction in the presence of H2
Impact of Bio-alcohol Fuels Combustion on Particulate Matter (PM) Morphology from Efficient Gasoline Direct Injection Engines
G-protein αq gene expression plays a role in alcohol tolerance in Drosophila melanogaster
Ethanol is a psychoactive substance causing both short- and long-term behavioural changes in humans and animal models. We have used the fruit fly Drosophila melanogaster to investigate the effect of ethanol exposure on the expression of the Gαq protein subunit. Repetitive exposure to ethanol causes a reduction in sensitivity (tolerance) to ethanol, which we have measured as the time for 50% of a set of flies to become sedated after exposure to ethanol (ST50). We demonstrate that the same treatment that induces an increase in ST50 over consecutive days (tolerance) also causes a decrease in Gαq protein subunit expression at both the messenger RNA and protein level. To identify whether there may be a causal relationship between these two outcomes, we have developed strains of flies in which Gαq messenger RNA expression is suppressed in a time- and tissue-specific manner. In these flies, the sensitivity to ethanol and the development of tolerance are altered. This work further supports the value of Drosophila as a model to dissect the molecular mechanisms of the behavioural response to alcohol and identifies G proteins as potentially important regulatory targets for alcohol use disorders
Structure of Nano-sized CeO2 Materials: Combined Scattering and Spectroscopic Investigations
The structure of several nano‐sized ceria, CeO2, systems was investigated using neutron and X‐ray diffraction and X‐ray absorption spectroscopy. Whilst both diffraction and total pair distribution functions (PDFs) revealed that in all of the samples the occupancy of both Ce4+ and O2− are very close to the ideal stoichiometry, the analysis using Reverse Monte Carlo technique revealed significant disorder around oxygen atoms in the nano‐sized ceria samples in comparison to the highly crystalline NIST standard. In addition, the analysis revealed that the main differences observed in the pair correlations from various X‐ray and neutron diffraction techniques were attributable to the particle size of the CeO2 prepared by the reported three methods. Furthermore, detailed analysis of the Ce L3‐ and K‐edge EXAFS data support this finding; in particular the decrease in higher shell coordination numbers with respect to the NIST standard, is attributed to differences in particle size
Effectiveness of a Regional Prepregnancy Care Program in Women With Type 1 and Type 2 Diabetes: Benefits beyond glycemic control
OBJECTIVE: To implement and evaluate a regional prepregnancy care program in women with type 1 and type 2 diabetes. RESEARCH DESIGN AND METHODS: Prepregnancy care was promoted among patients and health professionals and delivered across 10 regional maternity units. A prospective cohort study of 680 pregnancies in women with type 1 and type 2 diabetes was performed. Primary outcomes were adverse pregnancy outcome (congenital malformation, stillbirth, or neonatal death), congenital malformation, and indicators of pregnancy preparation (5 mg folic acid, gestational age, and A1C). Comparisons were made with a historical cohort (n = 613 pregnancies) from the same units during 1999-2004. RESULTS: A total of 181 (27%) women attended, and 499 women (73%) did not attend prepregnancy care. Women with prepregnancy care presented earlier (6.7 vs. 7.7 weeks; P < 0.001), were more likely to take 5 mg preconception folic acid (88.2 vs. 26.7%; P < 0.0001) and had lower A1C levels (A1C 6.9 vs. 7.6%; P < 0.0001). They had fewer adverse pregnancy outcomes (1.3 vs. 7.8%; P = 0.009). Multivariate logistic regression confirmed that in addition to glycemic control, lack of prepregnancy care was independently associated with adverse outcome (odds ratio 0.2 [95% CI 0.05-0.89]; P = 0.03). Compared with 1999-2004, folic acid supplementation increased (40.7 vs. 32.5%; P = 0.006) and congenital malformations decreased (4.3 vs. 7.3%; P = 0.04). CONCLUSIONS: Regional prepregnancy care was associated with improved pregnancy preparation and reduced risk of adverse pregnancy outcome in type 1 and type 2 diabetes. Prepregnancy care had benefits beyond improved glycemic control and was a stronger predictor of pregnancy outcome than maternal obesity, ethnicity, or social disadvantage
Calorimetric Investigation of Copper Binding in the N-Terminal Region of the Prion Protein at Low Copper Loading: Evidence for an Entropically Favorable First Binding Event
Although
the Cu<sup>2+</sup>-binding sites of the prion protein have been well
studied when the protein is fully saturated by Cu<sup>2+</sup>, the
Cu<sup>2+</sup>-loading mechanism is just beginning to come into view.
Because the Cu<sup>2+</sup>-binding modes at low and intermediate
Cu<sup>2+</sup> occupancy necessarily represent the highest-affinity
binding modes, these are very likely populated under physiological
conditions, and it is thus essential to characterize them in order
to understand better the biological function of copper–prion
interactions. Besides binding-affinity data, almost no other thermodynamic
parameters (e.g., Δ<i>H</i> and Δ<i>S</i>) have been measured, thus leaving undetermined the enthalpic and
entropic factors that govern the free energy of Cu<sup>2+</sup> binding
to the prion protein. In this study, isothermal titration calorimetry
(ITC) was used to quantify the thermodynamic parameters (<i>K</i>, Δ<i>G</i>, Δ<i>H</i>, and <i>T</i>Δ<i>S</i>) of Cu<sup>2+</sup> binding to
a peptide, PrP(23–28, 57–98), that encompasses the majority
of the residues implicated in Cu<sup>2+</sup> binding by full-length
PrP. Use of the buffer <i>N</i>-(2-acetomido)-aminoethanesulfonic
acid (ACES), which is also a well-characterized Cu<sup>2+</sup> chelator,
allowed for the isolation of the two highest affinity binding events.
Circular dichroism spectroscopy was used to characterize the different
binding modes as a function of added Cu<sup>2+</sup>. The <i>K</i><sub>d</sub> values determined by ITC, 7 and 380 nM, are
well in line with those reported by others. The first binding event
benefits significantly from a positive entropy, whereas the second
binding event is enthalpically driven. The thermodynamic values associated
with Cu<sup>2+</sup> binding by the Aβ peptide, which is implicated
in Alzheimer’s disease, bear striking parallels to those found
here for the prion protein
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