216 research outputs found

    Effects of Age on Meiosis in Budding Yeast

    Get PDF
    In humans, the frequency with which meiotic chromosome mis-segregation occurs increases with age. Whether age-dependent meiotic defects occur in other organisms is unknown. Here, we examine the effects of replicative aging on meiosis in budding yeast. We find that aged mother cells show a decreased ability to initiate the meiotic program and fail to express the meiotic inducer IME1. The few aged mother cells that do enter meiosis complete this developmental program but exhibit defects in meiotic chromosome segregation and spore formation. Furthermore, we find that mutations that extend replicative life span also extend the sexual reproductive life span. Our results indicate that in budding yeast, the ability to initiate and complete the meiotic program as well as the fidelity of meiotic chromosome segregation decrease with cellular age and are controlled by the same pathways that govern aging of asexually reproducing yeast cells.National Institutes of Health (U.S.) (Grant number GM62207)National Science Foundation (U.S.). (Grant number MCB-0342285)Howard Hughes Medical Institute. Investigato

    Playing projects: identifying flow in the 'lived experience'

    Get PDF
    The purpose of this paper is to contribute to the 'lived experience' of projects discourse. The research study uses an arts-based research method (musical improvisation on a xylophone and/or glockenspiel) to access the participant's perception of their experience of managing a project. Participants are then asked to explain their improvisation and therefore their experience. Key findings were that participants described their 'lived experience' of project managing as having 'ups and downs', including challenges and issues, and as experiencing variations in emotions over the project lifecycle. Csikszentmihalyi's flow theory is used to show that these 'lived experience' findings support a Heideggerian paradigm and personal perspective of what a project is. Projectness is not a characteristic of the activity itself. A project is a personal phenomenon defined in terms of the relationship between the individual or organisation and activity. It is dependent on capability versus the challenge presented by the activity

    Electroluminescent Characteristics of DBPPV–ZnO Nanocomposite Polymer Light Emitting Devices

    Get PDF
    We have demonstrated that fabrication and characterization of nanocomposite polymer light emitting devices with metal Zinc Oxide (ZnO) nanoparticles and 2,3-dibutoxy-1,4-poly(phenylenevinylene) (DBPPV). The current and luminance characteristics of devices with ZnO nanoparticles are much better than those of device with pure DBPPV. Optimized maximum luminance efficiencies of DBPPV–ZnO (3:1 wt%) before annealing (1.78 cd/A) and after annealing (2.45 cd/A) having a brightness 643 and 776 cd/m2at a current density of 36.16 and 31.67 mA/cm2are observed, respectively. Current density–voltage and brightness–voltage characteristics indicate that addition of ZnO nanoparticles can facilitate electrical injection and charge transport. The thermal annealing is thought to result in the formation of an interfacial layer between emissive polymer film and cathode

    Integrating Phosphorylation Network with Transcriptional Network Reveals Novel Functional Relationships

    Get PDF
    Phosphorylation and transcriptional regulation events are critical for cells to transmit and respond to signals. In spite of its importance, systems-level strategies that couple these two networks have yet to be presented. Here we introduce a novel approach that integrates the physical and functional aspects of phosphorylation network together with the transcription network in S.cerevisiae, and demonstrate that different network motifs are involved in these networks, which should be considered in interpreting and integrating large scale datasets. Based on this understanding, we introduce a HeRS score (hetero-regulatory similarity score) to systematically characterize the functional relevance of kinase/phosphatase involvement with transcription factor, and present an algorithm that predicts hetero-regulatory modules. When extended to signaling network, this approach confirmed the structure and cross talk of MAPK pathways, inferred a novel functional transcription factor Sok2 in high osmolarity glycerol pathway, and explained the mechanism of reduced mating efficiency upon Fus3 deletion. This strategy is applicable to other organisms as large-scale datasets become available, providing a means to identify the functional relationships between kinases/phosphatases and transcription factors

    Big data innovation and diffusion in projects teams: Towards a conflict prevention culture

    Get PDF
    Despite the enormous literature on how team conflicts can be managed and resolved, this study diverges, by examining factors that facilitate conflict prevention culture in project teams, especially when introducing Big Data Technology. Relying on findings from relevant literatures and focus group discussions, 28 attributes for embedding conflict prevention culture were identified and put together in questionnaire survey. Series of statistical tests including reliability analysis and exploratory factor-analysis. The results identified five critical success factors for entrenching the culture of conflict prevention in project teams introducing big data driving innovations. The five-factor solution include “building effective relationship”, “effective project communications”, “project team efficacy”, “pro-active conflict management approach” and “effectual project documentation”. Result of this study presents a Conceptual framework for effective management of human resource in relation to conflict prevention among project teams, as an effective strategy for facilitating seamless adoption and diffusion of big data innovation in organisations

    Fetal microglial phenotype in vitro carries memory of prior in vivo exposure to inflammation

    Get PDF
    Objective. Neuroinflammation in utero may result in life-long neurological disabilities. The molecular mechanisms whereby microglia contribute to this response remain incompletely understood. Methods. Lipopolysaccharide (LPS) or saline were administered intravenously to non-anesthetized chronically instrumented near-term fetal sheep to model fetal inflammation in vivo. Microglia were then isolated from in vivo LPS and saline (naĂŻve) exposed animals. To mimic the second hit of neuroinflammation, these microglia were then re-exposed to LPS in vitro. Cytokine responses were measured in vivo and subsequently in vitro in the primary microglia cultures derived from these animals. We sequenced the whole transcriptome of naĂŻve and second hit microglia and profiled their genetic expression to define molecular pathways disrupted during neuroinflammation.Results. In vivo LPS exposure resulted in IL-6 increase in fetal plasma 3 h post LPS exposure. Even though not histologically apparent, microglia acquired a pro-inflammatory phenotype in vivo that was sustained and amplified in vitro upon second hit LPS exposure as measured by IL-1ÎČ response in vitro and RNAseq analyses. While NFKB and Jak-Stat inflammatory pathways were up regulated in naĂŻve microglia, heme oxygenase 1 (HMOX1) and Fructose-1,6-bisphosphatase (FBP) genes were uniquely differentially expressed in the second hit microglia. Microglial calreticulin/LRP genes implicated in microglia-neuronal communication relevant for the neuronal development were up regulated in second hit microglia.Discussion. We identified a unique HMOX1down and FBPup phenotype of microglia exposed to the double-hit suggesting interplay of inflammatory and metabolic pathways as a memory of prior inflammatory insult. These findings suggest new therapeutic targets for early postnatal intervention to prevent brain injury
    • 

    corecore