Lineage tracing studies have revealed that transcription factors play a cardinal role in pancreatic development, differentiation and function. Three transitions define pancreatic organogenesis, differentiation and maturation. In the primary transition, when pancreatic organogenesis is initiated, there is active proliferation of pancreatic progenitor cells. During the secondary transition, defined by differentiation, there is growth, branching, differentiation and pancreatic cell lineage allocation. The tertiary transition is characterized by differentiated pancreatic cells that undergo further remodeling, including apoptosis, replication and neogenesis thereby establishing a mature organ. Transcription factors function at multiple levels and may regulate one another and auto-regulate. The interaction between extrinsic signals from non-pancreatic tissues and intrinsic transcription factors form a complex gene regulatory network ultimately culminating in the different cell lineages and tissue types in the developing pancreas. Mutations in these transcription factors clinically manifest as subtypes of diabetes mellitus. Current treatment for diabetes is not curative and thus, developmental biologists and stem cell researchers are utilizing knowledge of normal pancreatic development to explore novel therapeutic alternatives. This review summarizes current knowledge of transcription factors involved in pancreatic development and b-cell differentiation in rodents.

Flooding responses in Sporobolus virginicus (L.) Kunth., a perennial C grass, propagated from plants collected on the fringes of a mangrove swamp, were examined in a glasshouse study over 42 days. Flooding significantly reduced soil redox potential, induced adventitious root development, shifted resource allocation from below- to above-ground components without affecting total biomass accumulation and significantly decreased below-ground/above-ground biomass ratios. Although soil waterlogging significantly increased alcohol dehydrogenase activity (ADH) after 30 h, significant increase in central air space by 45-50% of the cross-sectional stem area eliminated root hypoxia, and ADH activity decreased to levels equivalent to drained controls after 42 days. In addition, flooded plants exhibited significantly higher carbon dioxide assimilation rates but similar relative growth rates (RGR) to drained controls. The results indicate that S. virginicus responds to water-logging by a combination of metabolic, morphological and anatomical mechanisms, which may account for its widespread distribution in coastal lagoons, estuaries and marshes.

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Managers are faced with the dilemma of either positioning their employees to compete against or to collaborate with each other within the organisation. Internal competition can motivate individuals and teams to strive to be the best and in so doing result in continuous incremental performance improvements. In contrast, internal collaboration can result in effective problem solving through knowledge sharing and innovation. This study investigated the key factors that drive the adoption of internal competition and internal collaboration, the consequences of implementing each approach, how levels of internal competition and internal collaboration vary at different management levels and whether a viable hybrid combination of both management approaches is possible. A qualitative exploratory study by in-depth interview was conducted with twenty senior executives. A hybrid model was developed from these research findings, which confirms that while the two management approaches have different outcomes there is an optimal way of combining them to allow managers to optimise the performance of their staff and the organisation.

This paper presents and assesses a simple model designed to quantify the desiccation sensitivity or degree of recalcitrance of the seeds of Trichilia dregeana, Ekebergia capensis and Quercus robur based on water content, water loss, and intensity and duration of water stress.

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