Clonal expansion under the microscope: studying lymphocyte activation and differentiation using live-cell imaging

Clonal expansion of lymphocytes is a hallmark of vertebrate adaptive immunity. A small number of precursor cells that recognize a specific antigen proliferate into expanded clones, differentiate and acquire various effector and memory phenotypes, which promote effective immune responses. Recent studies establish a large degree of heterogeneity in the level of expansion and in cell state between and within expanding clones. Studying these processes in vivo, while providing insightful information on the level of heterogeneity, is challenging due to the complex microenvironment and the inability to continuously track individual cells over extended periods of time. Live cell imaging of ex vivo cultures within micro fabricated arrays provides an attractive methodology for studying clonal expansion. These experiments facilitate continuous acquisition of a large number of parameters on cell number, proliferation, death and differentiation state, with single-cell resolution on thousands of expanding clones that grow within controlled environments. Such data can reveal stochastic and instructive mechanisms that contribute to observed heterogeneity and elucidate the sequential order of differentiation events. Intercellular interactions can also be studied within these arrays by following responses of a controlled number of interacting cells, all trapped within the same microwell. Here we describe implementations of live-cell imaging within microwell arrays for studies of lymphocyte clonal expansion, portray insights already gained from these experiments and outline directions for future research. These tools, together with in vivo experiments tracking single-cell responses, will expand our understanding of adaptive immunity and the ways by which it can be manipulated

Relational bonds and loyalty : the bonds that tie

This paper explores the effect of financial, social and structural bonds on the loyalty of Arabic five star hotel guests. Three different measures of loyalty are used; attitudinal, behavioural and combined to identify how the three relational bonds affect loyalty. The results show that social and structural bonds increase all types of loyalty whereas financial bonds only increase attitudinal and combined loyalty. It is also found that bonds are perceived to be more important for high-loyal consumers as compared to low-loyal consumers. This all suggests that firms seeking to increase loyalty may need different strategies depending on the consumers being targeted.<br /

Exploring the links between relational bonds and customer loyalty : the case of loyal Arabic guests at five-star hotels

Relationship marketing aims to build and maintain relationships between customers and organizations. While building strong bonds is a key objective of relationship marketing, limited empirical attention has been paid to the role of relational bonds on enhancing loyalty. This study explores the impact of financial, social and structural bonds on consumer loyalty, using a sample of loyal Arabic hotel guests. The results of this study suggest that structural bonds increase loyalty, although financial and social bonds were not found to have a significant impact on loyalty.<br /

A backward glance of who and what marketing scholars have been researching 1977-2002

Despite the diversity of all those involved within the marketing discipline, all have a stake in maximizing the advancement of marketing knowledge. Without a specific analysis it is difficult to reflect on where a field has been or where it might be heading. The purpose of this chapter is to examine who and what marketing scholars have been researching over the period 1977&ndash;2002 using content analysis. This chapter provides longitudinal benchmarking of the &lsquo;&lsquo;inputs&rsquo;&rsquo; (authors and institutions) and &lsquo;&lsquo;outputs&rsquo;&rsquo; (articles) examining the marketing literature in the four major marketing journals: the Journal of Marketing, the Journal of Marketing Research, the Journal of Consumer Research, and the Journal of the Academy of Marketing Science.<br /

Effects of supersymmetric grand unification scale physics on Γ(b→sγ)\Gamma \left( b\to s\gamma\right)

Although calculations of the $b\rightarrow s\gamma$ rate in supersymmetric grand unified models have always either ignored the gluino mediated contribution or found it to be negligible, we show that taking universal supersymmetry breaking masses at the Planck scale, rather than at the gauge unification scale as is customary, leads to the gluino contribution being more significant and in fact sometimes even larger than the chargino mediated contributions when $\mu >0$ and $\tan{\beta}$ is of order 1. The impact is greatest felt when the gluinos are relatively light. Taking the universal boundary condition at the Planck scale also has an effect on the chargino contribution by increasing the effect of the wino and higgsino-wino mediated decays. The neutralino mediated contribution is found to be enhanced, but nevertheless it remains relatively insignificant.Comment: Title changed, final version as accepted for PRD, 12 pages, 6 Figures (Figs.2-6 included, uuencoded, epsf.tex

A life cycle stakeholder management framework for enhanced collaboration between stakeholders with competing interests

This is a postprint version of the Book Chapter. Information regarding the official publication is available from the link below - Copyright @ 2011 SpringerImplementation of a Life Cycle Sustainability Management (LCSM) strategy can involve significant challenges because of competing or conflicting objectives between stakeholders. These differences may, if not identified and managed, hinder successful adoption of sustainability initiatives. This article proposes a conceptual framework for stakeholder management in a LCSM context. The framework identifies the key sustainability stakeholder groups and suggests strategic ambiguity as a management tool to harness dysfunctional conflict into constructive collaboration. The framework is of practical value as it can be used as a guideline by managers who wish to improve collaboration with stakeholders along the supply chain. The article also fills a gap in the academic literature where there is only limited research on sustainability stakeholder management through strategic ambiguity

The LHC (CMS) Discovery Potential for Models with Effective Supersymmetry and Nonuniversal Gaugino Masses

We investigate squark and gluino pair production at LHC (CMS) with subsequent decays into quarks, leptons and LSP in models with effective supersymmetry where third generation of squarks is relatively light while the first two generations of squarks are heavy. We consider the general case of nonuniversal gaugino masses. Visibility of signal by an excess over SM background in (n \geq 2)jets + (m \geq 0)leptons + E^{miss}_T events depends rather strongly on the relation between LSP, second neutralino, gluino and squark masses and it decreases with the increase of LSP mass. We find that for relatively heavy gluino it is very difficult to detect SUSY signal even for light 3^{rd} generation squarks (m_{\tilde q_3}\le 1 TeV) if the LSP mass is closed to the 3^{rd} generation squark mass.Comment: 1 latex (35 pages), 4 eps (figures) file