Retention mechanism divergence of a mixed mode stationary phase for high performance liquid chromatography

Mixed mode stationary phases utilize secondary retention mechanisms to add a dimensionality to the surface of high performance liquid chromatography (HPLC) adsorbents. This approach was used by several authors to improve the separation performance of single dimension separations. We explored the magnitude of these secondary interactions by performing an off-line two-dimensional (2D)-HPLC separation with a Scherzo SM-C18 column of a β-lactoglobulin tryptic digest with a mobile phase pH of 7 in the first dimension and 2 in the second. Mechanism divergence was determined using the peak capacity and a geometric approach to factor analysis, to measure the correlation. This separation was repeated with a C18 stationary phase as a control. It was found that the C18 column had a correlation coefficient of 0.784, smaller than the mixed mode column, 0.884. This indicated that the retention mechanisms of the C18 column were more divergent under these two pH environments than the mixed mode column. However, the SM-C18 still provided alternative selectivity of the peptides to that of the C18 and could be considered as a good alternative for further 2D-HPLC separations.

Skin friction coefficient on a yarn package surface in ring spinning

The skin friction coefficient on the surface of a rotating yarn package affects the power required to drive the package. This paper examines the relationship between the skin friction coefficient on the package surface and its diameter and rotating speed, based on the fundamentals of aerodynamics and the experimental results of power consumption. Skin friction coefficients on the surfaces of an airplane, car top, and yarn package are discussed. The results indicate that the skin friction coefficient on the package surface without hairiness depends on the package diameter and spindle speed only. The skin friction coefficient on the yarn package surface is about three times that on the top surface of a car, and is about twenty times that on an airplane surface. The power consumed to overcome skin friction drag is more than that consumed to drive the spindle if the spindle speed is very slow. However, the situation reverses when the spindle speed is fast.

Influence of the geometry of an immersed steel workpiece on mass transfer coefficient in a chemical heat treatment fluidised bed

The mass transfer during carburising in a fluidised bed and in a steel workpiece has been studied experimentally in this work. This involved carburising experiment in an electrically heated fluidised bed at 900–970°C with natural gas and air as the atmosphere. A steel workpiece was designed to provide a range of carbon transfer surfaces of different geometries in the fluidised bed, and the carbon transfer coefficient was measured at these surfaces. The carbon transfer coefficient was determined from the carbon distribution within the diffusion layer of the sample. An empirical relationship of the carbon potential as a function of carburising atmosphere, bed temperature and fluidising velocity was determined, based on the understanding of the mass transfer mechanism and analysis of the experimental results.

Application of bending under tension test to determine the effect of tool radius and the contact pressure on the coefficient of friction in sheet metal forming

To quantify the frictional behaviour in sheet forming operations, several laboratory experiments which simulate the real forming conditions are performed. The Bending Under Tension Test is one such experiment which is often used to represent the frictional flow of sheet material around a die or a punch radius. Different mathematical representations are used to determine the coefficient of friction in the Bending Under Tension Test. In general the change in the strip thickness in passing over the die radius is neglected and the radius of curvature to thickness ratio is assumed to be constant in these equations. However, the effect of roller radius, sheet thickness and the surface pressure are also omitted in some of these equations. This work quantitatively determined the effect of roller radius and the tooling pressure on the coefficient of friction. The Bending Under Tension Test was performed using rollers with different radii and also lubricants with different properties. The tool radii were found to have a direct influence in the contact pressure. The effect of roller radius on friction was considerable and it was observed that there is a clear relationship between the contact pressure and the coefficient of friction.

Retention of allied health professionals in the south-west of Victoria

The article reports on the research studies about the role of the allied health professionals in primary and preventive health care in Victoria. The studies shows that allied health practice in rural areas provide information on the strategies to maintain the health workforce. The results of the final report regarding the allied workforce issues in south-west Victoria was discussed. The details about the participants, methods and results of the survey regarding the retention of allied health professionals in south-west Victoria.

A conceptual model for recruitment and retention : allied health workforce enhancement in Western Victoria, Australia

Attracting and retaining allied health professionals in rural areas is a recognised problem in both Australia and overseas. Predicted increases in health needs will require strategic actions to enhance the rural workforce and its ability to deliver the required services. A range of factors in different domains has been associated with recruitment and retention in the allied health workforce. For example, factors can be related to the nature of the work, the personal needs, or the way an organisation is led. Some factors cannot be changed (eg geographical location of extended family) whereas others can be influenced (eg education, support, management styles). Recruitment and retention of allied health professionals is a challenging problem that deserves attention in all domains and preparedness to actively change established work practices, both individually as well as collectively, in order to cater for current and predicted health needs. Changes to enhance workforce outcomes can be implemented and evaluated using a cyclic model. The Allied Health Workforce Enhancement Project of the Greater Green Triangle University Department of Rural Health (GGT UDRH) is working towards increasing the number of allied health professionals in the south west of Victoria. Based on themes identified in the literature, an interactive model is being developed that addresses recruitment and retention factors in three domains: (1) personal or individual; (2) organisation; and (3) community.

Engagement and retention of participants in a physical activity website

Background: Websites have the potential to deliver enhanced versions of targeted and tailored physical activity programs to large numbers of participants. We describe participant engagement and retention with a stage-based physical activity website in a workplace setting. Methods:  We analyzed data from participants in the website condition of a randomized trial designed to test the efficacy of a print- vs. website-delivered intervention. They received four stage-targeted e-mails over 8 weeks, with hyperlinks to the website. Both objective and self-reported website use data were collected and analyzed. Results: Overall, 327 were randomized to the website condition and 250 (76%) completed the follow-up survey. Forty-six percent (n = 152) visited the website over the trial period. A total of 4,114 hits to the website were recorded. Participants who entered the site spent on average 9 min per visit and viewed 18 pages. Website use declined over time; 77% of all visits followed the first e-mail. Conclusions: Limited website engagement, despite the perceived usefulness of the materials, demonstrates possible constraints on the use of e-mails and websites in delivering health behavior change programs. In the often-cluttered information environment of workplaces, issues of engagement and retention in website-delivered programs require attention.

Relationship marketing, audience retention and performing arts organisation viability

Marketing strategy in performing arts organisations has become particularly important in the increasingly competitive environment in which the arts operate. Since the late 1980s there has been a necessary shift in focus to audience development away from product development. This change in focus is being encouraged to ensure the long-term viability of performing arts organisations (PAOs) and micro-economic reform. While government reports have recommended strategies aimed at building audience based recognition, this is an expensive approach for many PAOs and does not produce short term returns. Little attention has been paid to building enduring relationships with existing audiences as a way if having a more dramatic impact on PAOs' long-term viability. This paper explores this theme through relationship marketing and the implication of retaining existing audiences. The paper identifies the changing cultural environment which has led to the importance if marketing. It then explains the concepts if relationship marketing and its pertinence to PAOs' viability by presenting a loyalty ladder. The structure is modelled as a dynamic conceptualisation of the relationships (audience and organisation) to assist arts managers to decide whether to focus their efforts on catching or keeping customers to maximise earned income.

Carburising and carbon transfer coefficient in a fluidised bed furnance

The carburising of a steel workpiece with complex geometry in a fluidised bed hasbeen studied experimentally. This involved carburising experiment in an electrically heated fluidised bed at 900 - 970°C with natural gas and air as the atmosphere. The carbon transfer coefficient at the workpiece surface and diffusivity within the workpiece were determined from the carbon distribution within the diffusion layer of the sample. A reverse method and the Levenberg-Marquardt algorithm were used in the calculations. The methodology of the reverses method to extract the carbon transfer coefficient and diffusivity is also discussed in some detail.

Retention of essential amino acids during extrusion of protein and reducing sugars

This research investigates the retention of essential amino acid profiles of products during the extrusion of proteins and reducing sugars. Animal proteins (egg and milk protein at 10 and 30% levels) and reducing sugars (fructose and galactose at 0, 2, and 8% levels), with pregelatinized wheat flour, were extruded at 110 and 125 °C product temperatures and feed moistures of 19 and 23.5% for egg protein and 13.75 and 16% for milk protein. The nutritional property analyzed was essential amino acid retention, and sugar retention was also considered to understand the relationship of sugars with retention of amino acids. Lysine showed the lowest retention (up to 40%) of all the essential amino acids. Retention of other essential amino acids varied from 80 to 100% in most situations. Apart from lysine,  tryptophan, threonine, and methionine were found to be significantly changed (P < 0.05) with processing conditions. Increased protein and sugar levels resulted in a significant degradation of lysine. Greater lysine retention was found at a lower temperature and higher feed moisture. Results of sugar retention also showed similar patterns. The products made from fructose had greater lysine retention than products made from galactose with any type of protein. The outcomes of this research suggested that the combination of milk protein and fructose at a lower temperature and higher feed moisture is most favorable for developing high-protein extruded products.