The cultural embeddedness of professional service purchasing-A comparative study of German and Swedish companies

Research on professional service purchasing generally takes a culturally universalistic approach, implicitly assuming the generalizability of research findings and normative models to different cultural contexts. However, research in related disciplines points to the influence of national culture on managers' decisions, thereby questioning the culturally universalistic approach. The purpose of this paper is to explore differences in professional service purchasing in different cultural contexts. Based on a survey of large organizations, we analyze how the purchasing process for a specific type of professional services - management consulting services - is organized in two cultural contexts (i.e. Germany and Sweden). The results indicate that organizations in Germany and Sweden differ in the way they approach key aspects of the purchasing process. These differences are discussed in relation to two central cultural dimensions - uncertainty avoidance and masculinity-femininity - in which Germany and Sweden take very different positions. It is proposed that uncertainty avoidance mainly influences the first steps in the purchasing process (specify, select and contract) whereas masculinity-femininity mainly influences the remaining steps (order, expedite and evaluate). The paper contributes to the purchasing and supply management literature by empirically illustrating differences in purchasing practices in different cultural contexts and developing theory-driven propositions for the influence of national culture on the professional service purchasing process

Developmental origin and maintenance of distinct testicular macrophage populations

International audienceTesticular macrophages (tM phi) are the principal immune cells of the mammalian testis. Beyond classical immune functions, they have been shown to be important for organogenesis, spermatogenesis, and male hormone production. In the adult testis, two different macrophage populations have been identified based on their distinct tissue localization and morphology, but their developmental origin and mode of homeostatic maintenance are unknown. In this study, we use genetic lineage-tracing models and adoptive transfer protocols to address this question. We show that embryonic progenitors give rise to the interstitial macrophage population, whereas peritubular macrophages are exclusively seeded postnatally in the prepuberty period from bone marrow (BM)-derived progenitors. As the proliferative capacity of interstitial macrophages declines, BM progenitors also contribute to this population. Once established, both the peritubular and interstitial macrophage populations exhibit a long life span and a low turnover in the steady state. Our observations identify distinct developmental pathways for two different tM phi populations that have important implications for the further dissection of their distinct roles in organ homeostasis and testicular function

Characterisation of Genome-Wide PLZF/RARA Target Genes

The PLZF/RARA fusion protein generated by the t(11;17)(q23;q21) translocation in acute promyelocytic leukaemia (APL) is believed to act as an oncogenic transcriptional regulator recruiting epigenetic factors to genes important for its transforming potential. However, molecular mechanisms associated with PLZF/RARA-dependent leukaemogenesis still remain unclear

Macrophage origin and self-renewal

International audienceno abstrac

Creating a blood line from human skin.

International audienceABSTRACT : A recent study has generated blood cell progenitors with therapeutic potential by direct lineage conversion of human fibroblasts, thus circumventing reprogramming to pluripotent stem cells

Mutations of brainstem transcription factors and central respiratory disorders.

Several pathologies, such as central hypoventilation syndrome, central sleep apnea and cases of sudden infant death syndrome, involve defects in central breathing control. On a cellular and molecular level these disorders remain poorly defined and mechanistically not understood. A complex network of distinct brainstem neurons coordinates respiratory rhythm generation and modulation, which traditionally has been mapped by anatomical, physiological and pharmacological techniques. Recently, targeted gene inactivation of several transcription factors in mice was found to affect the development of specific groups of brainstem neurons and result in distinct respiratory phenotypes. These mutants promise a higher precision in the analysis of central breathing control and new diagnostic perspectives for respiratory syndromes, as indicated by the recent discovery of corresponding mutations in humans

Integration of cytokine and transcription factor signals in hematopoietic stem cell commitment.

International audienceIn the predominant model of hematopoietic stem cell differentiation lineage commitment is thought to be initiated by stochastic variation in the balance of lineage determining transcription factors, whereas cytokines have been seen in a purely permissive role of stimulating selective survival and proliferation of the down stream progeny. Recent observations, however, indicate that cytokines can also directly instruct cell fate change in uncommitted stem and progenitor cells by activating lineage determining transcription factors. We review the historic and recent evidence for instructive cytokine signaling and propose a model that integrates cytokine signaling and transcription factor activity in the initial decision making process, where the sensitivity to external instructive signals can be modulated by internal threshold setters. In contrast to a rigid stochastic explanation of lineage commitment this view allows for receptiveness of the hematopoietic stem cell to its environment and exposes lineage commitment as dependent on both instructive signals and cell intrinsically controlled sensitivity to external cues