Symmetric and asymmetric divisions are important for self-renewal and differentiation of stem cells during neurogenesis. Although cerebellar granule neurogenesis is controlled by sonic hedgehog (SHH) signaling, whether and how this process is mediated by regulation of cell division modes have not been determined. Here, using time-lapse imaging and cell culture from neuronal progenitor-specific ...

Reaching the limit of cell divisions, a phenomenon referred to as replicative aging, of the yeast Saccharomyces cerevisiae involves a progressive increase in the cell volume. However, the exact relationship between the number of cell divisions accomplished (replicative age), the potential for further divisions and yeast cell volume has not been investigated thoroughly. In this study an increase...

Introduction Stem cells in adult self-renewing tissues Haemopoiesis Epidermis Gastrointestinal epithelium General characteristics of stem cells Asymmetric divisions Predetermined asymmetry Yeast C. elegans What are the mechanisms of predetermined asymmetric divisions? Asymmetry without lineage involvement Stochastic events Stem cell heterogeneity Environmental regulation Conclusions What is the...

Like animals, plants use asymmetric cell divisions to create pattern and diversity. Due to a rigid cell wall and lack of cell migrations, these asymmetric divisions incur the additional constraints of being locked into their initial orientations. How do plants specify and carry out asymmetric divisions? Intercellular communication has been suspected for some time and recent developments identif...

We consider the transfer pricing decision for a multidivisional firm with an upstream division and multiple downstream divisions. The downstream divisions can independently determine their retail prices, and decide on whether or not they will purchase from the upstream division at negotiated transfer prices. To allocate the firm-wide profit between upstream and downstream divisions, we construc...

Cell divisions producing two daughter cells that adopt distinct fates are defined as asymmetric. In all organisms, ranging from bacteria to mammals, in which development has been studied extensively, asymmetric cell divisions generate cell diversity. Asymmetric cell divisions can be achieved by either intrinsic or extrinsic mechanisms (Fig. 1). Intrinsic mechanisms involve the preferential segr...

This paper studies optimal organization structures in multidivisional organizations with more than two divisions. The decisions of individual divisions need to be adapted to local conditions and also be coordinated. The needs for coordination are described by a coordination network. Information about local conditions is held by division managers who communicate strategically. Hierarchy is an or...

BACKGROUND Since the late 1980s, there has been evidence of an international trend towards more organised primary care. This has taken a number of forms including the emergence of primary care organisations. Underpinning such developments is an inherent belief in evidence that suggests that well-developed primary care is associated with improved health outcomes and greater cost-effectiveness wi...

A key feature of many adult stem cell lineages is that stem cell daughters destined for differentiation undergo several transit amplifying (TA) divisions before initiating terminal differentiation, allowing few and infrequently dividing stem cells to produce many differentiated progeny. Although the number of progenitor divisions profoundly affects tissue (re)generation, and failure to control ...