783 resultados para Dianne Hoff


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The possibility to compress analyte bands at the beginning of CE runs has many advantages. Analytes at low concentration can be analyzed with high signal-to-noise ratios by using the so-called sample stacking methods. Moreover, sample injections with very narrow initial band widths (small initial standard deviations) are sometimes useful, especially if high resolutions among the bands are required in the shortest run time. In the present work, a method of sample stacking is proposed and demonstrated. It is based on BGEs with high thermal sensitive pHs (high dpH/dT) and analytes with low dpK(a)/dT. High thermal sensitivity means that the working pK(a) of the BGE has a high dpK(a)/dT in modulus. For instance, Tris and Ethanolamine have dpH/dT = -0.028/degrees C and -0.029/degrees C, respectively, whereas carboxylic acids have low dpK(a)/dT values, i.e. in the -0.002/degrees C to+0.002/degrees C range. The action of cooling and heating sections along the capillary during the runs affects also the local viscosity, conductivity, and electric field strength. The effect of these variables on electrophoretic velocity and band compression is theoretically calculated using a simple model. Finally, this stacking method was demonstrated for amino acids derivatized with naphthalene-2,3-dicarboxaldehyde and fluorescamine using a temperature difference of 70 degrees C between two neighbor sections and Tris as separation buffer. In this case, the BGE has a high pH thermal coefficient whereas the carboxylic groups of the analytes have low pK(a) thermal coefficients. The application of these dynamic thermal gradients increased peak height by a factor of two (and decreased the standard deviations of peaks by a factor of two) of aspartic acid and glutamic acid derivatized with naphthalene-2,3-dicarboxaldehyde and serine derivatized with fluorescamine. The effect of thermal compression of bands was not observed when runs were accomplished using phosphate buffer at pH 7 (negative control). Phosphate has a low dpH/dT in this pH range, similar to the dK(a)/dT of analytes. It is shown that vertical bar dK(a)/dT-dpH/dT vertical bar >> 0 is one determinant factor to have significant stacking produced by dynamic thermal junctions.

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In a previous work [M. Mandaji, et al., this issue] a sample stacking method was theoretically modeled and experimentally demonstrated for analytes with low dpK(a)/dT (analytes carrying carboxylic groups) and BGEs with high dpH/dT (high pH-temperature-coefficients). In that work, buffer pH was modulated with temperature, inducing electrophoretic mobility changes in the analytes. In the present work, the opposite conditions are studied and tested, i.e. analytes with high dpK(a)/dT and BGEs that exhibit low dpH/dT. It is well known that organic bases such as amines, imidazoles, and benzimidazoles exhibit high dpK(a)/dT. Temperature variations induce instantaneous changes on the basicity of these and other basic groups. Therefore, the electrophoretic velocity of some analytes changes abruptly when temperature variations are applied along the capillary. This is true only if BGE pH remains constant or if it changes in the opposite direction of pK(a) of the analyte. The presence of hot and cold sections along the capillary also affects local viscosity, conductivity, and electric field strength. The effect of these variables on electrophoretic velocity and band stacking efficacy was also taken into account in the theoretical model presented. Finally, this stacking method is demonstrated for lysine partially derivatized with naphthalene-2,3-dicarboxaldehyde. In this case, the amino group of the lateral chain was left underivatized and only the alpha amino group was derivatized. Therefore, the basicity of the lateral amino group, and consequently the electrophoretic mobility, was modulated with temperature while the pH of the buffer used remained unchanged.

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Resistance to change has long been recognised as a critically important factor that can influence the success or otherwise of implementing any 'technological innovation. Information technology (IT) focused interventions, for example, business process re-engineering (BPR) and enterprise resource planning (ERP), are often quoted as examples of costly failures, with reported levels of dissatisfaction ·with strategic IT investments ranging from 20-70 percent and that employee resistance was to blame. The intention of this chapter is to rethink resistance. The author suggests that resistance remains to this day a complex, multifaceted phenomenon that continues to affect the outcomes of change, both negatively and positively. Although research has procured a solid understanding of resistance- and the benefits that can accrue to an organisation through its proper utilisation, it appears that the classical adversarial approach remains the dominant means ofmanaging resistance because such learning is not reflected in modern management techniques. The author concludes that as companies in every industry are now translating the power and possibilities 0/ e-business into strategic and operational realities, newapproaches in change managementare required to help organisations to understand the complex dynamics o/technological innovation and especially the multifaceted nature o/resistance.

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A business is a multifaceted organism; made up of mutually dependent employees whose connection to each other is largely dependant on their role within the entity. Being in a family is a very similar experience. So when family and business interact, managing both can be a challenge. This case study focuses on issues that contribute to a successful family business infrastructure, and the issues and trends that they identify as significant - for example, the importance of a succession plan within the family business environment.

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The internet revolution has affected everybody in some way. Technologies used in business range from telephones to industry-specific machinery. Mostly though, business technology has come to mean the internet. In literature concerning innovation and the adoption of technology in business, research invariably centres on small to medium businesses (SI'v1Es), as these can be defined reasonably easily. Statistics on family businesses are limited, however, because family businesses are so difficult to categorize and define.

The Australian Family Business Survey of 1993 (Institute of Chartered Accountants) determined that family business is the largest form of business ownership in Australia and represents 83% of all business enterprises, although Basu (2004) believes that over two thirds of all world-wide businesses are owned or managed by families and around half of all businesses in Australia are family businesses. The Australian Institute of Management (AIM) (2004) states that the wealth of family and private businesses is estimated at $3.6 trillion and that family firms generate 50 per cent of Australia's employment growth, account for 40 per cent of Australia's private sector output, and are a seed bed for innovation and the information of large companies.

The difficulty in defining a family business is heightened because family businesses can take many forms ranging from sole traders to private companies to public companies. Hence, when talking about family business, you could be referring to the sole trader dealing with organic produce to an IT organisation employing hundreds of staff. Basu (2004) thinks that while ordinarily, in non-family businesses, the business and family domains remain separate, the key distinctive characteristic of family businesses is that family members work together for economic purposes. In other words, the family is not merely a social unit but also an economic unit. Craig and Lindsay (2002) believe that family involvement in the business is what makes the family business different... researchers, however, cannot seem to agree as to what constitutes 'family involvement' in a business so that it can be defined as a family business and that family business is ... a business that is governed and/or managed with the intention to shape and pursue the vision of the business held by a dominant coalition that is controlled by members of the same family or a small number of families in a manner that is potentially sustainable across generations of the family or families.

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Managing the family business is a timely and thought provoking book that should encourage greater debate about where family businesses are going and what issues are paramount. The editors have made a consious attempt to invite and encourage academic and industry practitioners to contribute chapters.

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This chapter highlights and discusses entrepreneurial opportunities on the Internet. It provides a brief introduction to entrepreneurship, examines the characteristics of entrepreneurs, and talks about cyber entrepreneurs. It includes a case study which demonstrates the opportunities and challenges of cyber entrepreneurship. The case study illustrates the ease of setting up a business on the Internet by the younger generation with little capital and resource requirement. It highlights the fact that an intensive marketing campaign, perseverance, and some technical knowledge are important traits of cyber entrepreneurs. The other issues apparent from the case study are an opportunistic mindset, innovation, and the ability to create value where there was none before.

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The purpose of this paper is to use Kane's notion of the regulatory dialectic to analyse the changing nature of bank regulation in Australia. Throughout Australia's economic history, economic regulation of the Australian banking system has not been static but has responded to changes in technology, market forces, and the behaviour of regulated institutions. From this analysis, some inferences about general banking principles and policy can be made.

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Eucalyptus crenulata is a rare species known from only two populations. The Buxton Silver Gum Reserve was set aside in 1978 for the conservation of the species, but this objective may be compromised by changes in the integrity of the landscape immediately surrounding the Reserve. A time sequence of aerial photos and Geographic Information Systems technology has been used to identify patterns of landscape change, and aid in determining appropriate management strategies to minimize negative impacts caused by landscape fragmentation and habitat exposure

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The reduction of loss of lives and assets during bushfire is one of the primary aims or lire management agencies. Traditional fire mitigation strategies include strategic fire hreaks, static water points, management of ignition sources, rapid detection and local response, air attack, and fuel reduction burning. There have been few quantitative studies that assess the success or these strategies. We need to promote 'new' strategies more focused on human hehaviour and community preparedness.
DeJcndable space provides our best strategy for reducing losses during major bushfires. The size or the defendable space depends on the type of house to be defended, who is defending it, and the spatial context of the property. In the urban fi'inge, remnant vegetation on private property often has
high conservation values, and application of traditional mitigation strategies, as well as the vegetation modification required to achieve defendable space, may have significant impacts on conservation and biodiversity values.