Procedures for analysis of strain transfer in the acetabular region in vitro

The failure of acetabular cups via loosening, migration or fracture is partially related to the stress distribution existing in the acetabular region. The complexity of the investigation of these stresses demands the application of a variety of model testing techniques involving combined embedded strain gauging, finite element analysis, transmission and reflective photoelasticity and crack propagation studies. The application of these procedures are described and the difficulties of obtaining representative loadings and restraints are commented upon.     

Correlation of vibrational intensity with fluorescence lifetimes in π conjugated polymers

A series of novel pi (π) conjugated polymers, originating from the archetypical Polyphenylene vinylene, in which the phenyl units are successively replaced by the larger naphthyl and anthryl acene units, were previously found to have a well-defined relationship between their relative fluorescence yields and their vibrational characteristics, as determined by Raman spectroscopy. In this study the Strickler-Berg equation is used to probe the influence of continual substitution of higher order acene units into the conjugated backbone in terms of the variation of the radiative and non-radiative rates. The deconvolution of the radiative and non-radiative rates enables the correlation of the reduction of the Raman intensity and concomitant increase in the fluorescence yield with the reduction of the non-radiative rate. This confirms that the reduction of the non-radiative rate is the dominant process introduced by the vibrational confinement originating from systematic substitution of higher order acene units into the polymer backbone.     

Carbohydrate type and amount alter intravascular processing and catabolism of plasma lipoproteins in guinea pigs

To test the effects of exchanging dietary complex and simple carbohydrate for fat calories on lipoprotein metabolism, guinea pigs were fed two different fat/carbohydrate ratios: 2.5∶58% (w/w) or 25∶29% (w/w) with either sucrose or starch as the carbohydrate source. Animals fed high-fat had higher plasma low-density lipoprotein (LDL) and hepatic cholesterol concentrations than animals fed low-fat diets (P<0.01). The cholesteryl ester content per particle was higher, and the number of triacylglycerol (TAG) molecules was lower in very low density lipoprotein (VLDL) and LDL from animals fed high-fat diets. Intake of high-fat/sucrose resulted in higher plasma LDL concentrations than intake of high-fat/starch, and animals fed low-fat/starch had the highest plasma TAG concentrations associated with VLDL particles containing more TAG molecules, as well as a TAG-enriched LDL. The activity of plasma lecithin cholesteryl:acyl transferase (LCAT) was highest in animals fed high-fat/sucrose, and heart lipoprotein lipase (LPL) activity was higher in animals fed high-fat diets. Hepatic apoprotein B/E (apo B/E) receptor number (B_max) was increased 21% with low-fat diets (P<0.01). These results suggest that the hypercholesterolemia induced by high-fat and by sucrose intake are associated with a higher plasma LCAT activity which results in a cholesteryl ester-enriched VLDL which, by the action of LPL, might be more readily converted to LDL through the delipidation cascade leading to downregulation of hepatic apo B/E receptors. The hypertriglyceridemia associated with low-fat intake may result from increased production of VLDL TAG, which would explain the increased TAG content and the higher TAG/CE ratio of VLDL from animals fed the low-fat/starch diet.     

Evaluation of diamond films by nuclear magnetic resonance and Raman spectroscopy

The quality of chemically vapor deposited diamond films was assessed in terms of sp²/sp³ content as determined by solid-state nuclear magnetic resonance (NMR) and Raman spectroscopy. While the results of the two techniques are in qualitative agreement, only the NMR spectra yield quantitative values for the sp²/sp³ ratio. Only sp³ carbon was observed in the NMR spectra of very high quality hot-filament, microwave plasma, and d.c. arc-jet chemically vapor deposited films. As expected, Raman spectroscopy is extremely sensitive to sp² bonded carbon, identifying small amounts below the detection limit of the NMR spectrometer. Comparison of the two techniques, however, indicates that Raman spectroscopy may be so sensitive to sp² bonded carbon that sp³ bonded carbon in films containing as much as 90% sp³ bonded material may remain undetected. NMR linewidths indicate that the sp³ carbon in such material shows more disorder than that found in high-quality polycrystalline films.     

It's the Thought that Counts: The Mediating Effects of Information Processing in Virtual Team Decision Making

Abstract

Previous research shows that although collaboration technology can improve the exchange of information during team decision making, one of the challenges is that this better discussion often does not lead to better decisions. In this paper, we investigate the impact of individual information processing on team decision making. We investigated the effects of two types of collaboration technology when participants were either the member of a team majority or a team minority. There was little impact due to the majority/minority, but the use of collaboration technology that required users to categorize the comments they received from others resulted in increased information processing, which in turn led to better decisions and more satisfied participants.     

Power up! Using Digital Gaming Techniques to Enhance Library Instruction

ABSTRACT

Incorporating digital gaming into education is an increasingly popular topic in academia. Educators’ views of digital gaming (e.g., computer, video, and online games) have shifted from categorizing these games as an entertaining, yet pedagogically void activity to a promising medium that engages students in the learning process. With over 70% of college students enthusiastically playing digital games, educators are tapping into digital gaming as an effective means to teach millennials problem solving and communication skills. This article investigates gamer characteristics, motivational and engaging aspects of digital games, and the parallels between gaming and the information retrieval process. The authors build on this information to present approaches to incorporate digital gaming techniques into the library classroom since it is not feasible for all libraries to create instructional digital games.     

Precarious employment, working hours, work-life conflict and health in hotel work

Precarious or temporary work is associated with adverse outcomes including low control over working hours, work-life conflict and stress. The rise in precarious employment is most marked in the service sector but little research has been done on its health effects in this sector. This study compares permanent and temporary workers in the hotel industry, where working hours are highly variable. Survey data from 150 workers from eight 3-Star hotels in urban and regional areas around Sydney were analyzed. Forty-five per cent were male and 52 per cent were female. Fifty four per cent were permanent full-time and 46 per cent were temporary workers. The effects of employment status on perceived job security, control over working hours, and work-life conflict are investigated using PLS-Graph 3.0. The effects of control over working hours, on work-life conflict and subsequent health outcomes are also explored. Temporary workers perceived themselves as less in control of their working hours, than permanent workers (β = .27). However, they also reported lower levels of work intensity (β = .25) and working hours (β = .38). The effects of low hours control (β = .20), work intensity (β = .29), and excessive hours (β = .39) on work-life conflict (r² = .50), and subsequent health effects (r² = .30), are illustrated in the final structural equation model.     

Inexact graph matching based on kernels for object retrieval in image databases

In the framework of online object retrieval with learning, we address the problem of graph matching using kernel functions. An image is represented by a graph of regions where the edges represent the spatial relationships. Kernels on graphs are built from kernel on walks in the graph. This paper firstly proposes new kernels on graphs and on walks, which are very efficient for graphs of regions. Secondly we propose fast solutions for exact or approximate computation of these kernels. Thirdly we show results for the retrieval of images containing a specific object with the help of very few examples and counter-examples in the framework of an active retrieval scheme.     

Correlations between flaw tolerance and reliability in zirconia

Interrelations between flaw tolerance and reliability in Y-TZP, Ce-TZP and Mg-PSZ ceramics are investigated. Indentation-strength tests indicate an enhanced flaw tolerance with increasing R-curve behaviour from tetragonal martensite transformation. The Weibull modulus of unindented specimens increases with the enhanced tolerance. However, even the most tolerant zirconias show persistent scatter in strength, implying that variability in material microstructure may be as important a factor in reliability evaluation in these materials as variability in flaw size.