65 research outputs found

    Assessing availability and greenhouse gas emissions of lignocellulosic biomass feedstock supply – case study for a catchment in England

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    © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.Feedstocks from lignocellulosic biomass (LCB) include crop residues and dedicated perÂŹennial biomass crops. The latter are often considered superior in terms of climate change mitigation potential. Uncertainty remains over their availability as feedstocks for biomass provision and the net greenhouse gas emissions (GHG) during crop production. Our objective was to assess the optimal land allocation to wheat and Miscanthus in a specific case study located in England, to increase bioÂŹmass availability, improve the carbon balance (and reduce the consequent GHG emissions), and miniÂŹmally constrain grain production losses from wheat. Using soil and climate variables for a catchment in east England, biomass yields and direct nitrogen emissions were simulated with validated process-based models. A ‘Field to up-stream factory gate’ life-cycle assessment was conducted to estimate indirect management-related GHG emissions. Results show that feedstock supply from wheat straw can be supplemented beneficially with LCB from Miscanthus grown on selected low-quality soils. In our study, 8% of the less productive arable land area was dedicated to Miscanthus, increasing total LCB provision by about 150%, with a 52% reduction in GHG emission per ton LCB delivered and only a minor effect on wheat grain production (−3%). In conclusion, even without considering the likely carbon sequestration in impoverished soils, agriculture should embrace the opportunities to provide the bioeconomy with LCB from dedicated, perennial crops.Peer reviewe

    Perspectives on a ‘Sit Less, Move More’ Intervention in Australian Emergency Call Centres

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    Background: Prolonged sitting is associated with increased risk of chronic diseases. Workplace programs that aim to reduce sitting time (sit less) and increase physical activity (move more) have targeted desk-based workers in corporate and university settings with promising results. However, little is known about 'move more, sit less' programs for workers in other types of jobs and industries, such as shift workers. This formative research examines the perceptions of a 'sit less, move more' program in an Australian Emergency Call Centre that operates 24 hours per day, 7 days per week.  Methods: Participants were employees (N = 39, 72% female, 50% aged 36-55 years) recruited from Emergency Services control centres located in New South Wales, Australia. The 'sit less, move more' intervention, consisting of emails, posters and timer lights, was co-designed with the management team and tailored to the control centre environment and work practices, which already included electronic height-adjustable sit-stand workstations for all call centre staff. Participants reported their perceptions and experiences of the intervention in a self-report online questionnaire, and directly to the research team during regular site visits. Questionnaire topics included barriers and facilitators to standing while working, mental wellbeing, effects on work performance, and workplace satisfaction. Field notes and open-ended response data were analysed in an iterative process during and after data collection to identify the main themes.  Results: Whilst participants already had sit-stand workstations, use of the desks in the standing position varied and sometimes were contrary to expectations (e.g, less tired standing than sitting; standing when experiencing high call stress). Participants emphasised the "challenging" and "unrelenting" nature of their work. They reported sleep issues ("always tired"), work stress ("non-stop demands"), and feeling mentally and physically drained due to shift work and length of shifts. Overall, participants liked the initiative but acknowledged that their predominantly sitting habits were entrenched and work demands took precedence.  Conclusions: This study demonstrates the low acceptability of a 'sit less, move more' program in shift workers in high stress environments like emergency call centres. Work demands take priority and other health concerns, like poor sleep and high stress, may be more salient than the need to sit less and move more during work shifts

    Integrating Communities of Practice in Technology Development Projects

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    Technology development projects usually benefit when knowledge and expertise are drawn from a variety of sources, including potential users. Orchestrating the involvement of people from disparate groups is a crucial task for project managers. It requires finding a balance between differentiation, when teams work in isolation, and integration, when groups come together to exchange knowledge. This article argues that a “community of practice” perspective can help project managers to achieve this balance, by drawing attention to the assumptions, interests, skills, and formal and tacit knowledge of the different groups involved. Successful integration can be achieved by ensuring that the developing technology is comprehensible to all the groups concerned, and making sure that it satisfies their various interests

    Tor1/Sch9-Regulated Carbon Source Substitution Is as Effective as Calorie Restriction in Life Span Extension

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    The effect of calorie restriction (CR) on life span extension, demonstrated in organisms ranging from yeast to mice, may involve the down-regulation of pathways, including Tor, Akt, and Ras. Here, we present data suggesting that yeast Tor1 and Sch9 (a homolog of the mammalian kinases Akt and S6K) is a central component of a network that controls a common set of genes implicated in a metabolic switch from the TCA cycle and respiration to glycolysis and glycerol biosynthesis. During chronological survival, mutants lacking SCH9 depleted extracellular ethanol and reduced stored lipids, but synthesized and released glycerol. Deletion of the glycerol biosynthesis genes GPD1, GPD2, or RHR2, among the most up-regulated in long-lived sch9Δ, tor1Δ, and ras2Δ mutants, was sufficient to reverse chronological life span extension in sch9Δ mutants, suggesting that glycerol production, in addition to the regulation of stress resistance systems, optimizes life span extension. Glycerol, unlike glucose or ethanol, did not adversely affect the life span extension induced by calorie restriction or starvation, suggesting that carbon source substitution may represent an alternative to calorie restriction as a strategy to delay aging

    A Microarray-Based Genetic Screen for Yeast Chronological Aging Factors

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    Model organisms have played an important role in the elucidation of multiple genes and cellular processes that regulate aging. In this study we utilized the budding yeast, Saccharomyces cerevisiae, in a large-scale screen for genes that function in the regulation of chronological lifespan, which is defined by the number of days that non-dividing cells remain viable. A pooled collection of viable haploid gene deletion mutants, each tagged with unique identifying DNA “bar-code” sequences was chronologically aged in liquid culture. Viable mutants in the aging population were selected at several time points and then detected using a microarray DNA hybridization technique that quantifies abundance of the barcode tags. Multiple short- and long-lived mutants were identified using this approach. Among the confirmed short-lived mutants were those defective for autophagy, indicating a key requirement for the recycling of cellular organelles in longevity. Defects in autophagy also prevented lifespan extension induced by limitation of amino acids in the growth media. Among the confirmed long-lived mutants were those defective in the highly conserved de novo purine biosynthesis pathway (the ADE genes), which ultimately produces IMP and AMP. Blocking this pathway extended lifespan to the same degree as calorie (glucose) restriction. A recently discovered cell-extrinsic mechanism of chronological aging involving acetic acid secretion and toxicity was suppressed in a long-lived ade4Δ mutant and exacerbated by a short-lived atg16Δ autophagy mutant. The identification of multiple novel effectors of yeast chronological lifespan will greatly aid in the elucidation of mechanisms that cells and organisms utilize in slowing down the aging process

    Effects of calorie restriction on life span of microorganisms

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    Calorie restriction (CR) in microorganisms such as budding and fission yeasts has a robust and well-documented impact on longevity. In order to efficiently utilize the limited energy during CR, these organisms shift from primarily fermentative metabolism to mitochondrial respiration. Respiration activates certain conserved longevity factors such as sirtuins and is associated with widespread physiological changes that contribute to increased survival. However, the importance of respiration during CR-mediated longevity has remained controversial. The emergence of several novel metabolically distinct microbial models for longevity has enabled CR to be studied from new perspectives. The majority of CR and life span studies have been conducted in the primarily fermentative Crabtree-positive yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, but studies in primarily respiratory Crabtree-negative yeast and obligate aerobes can offer complementary insight into the more complex mammalian response to CR. Not only are microorganisms helping characterize a conserved cellular mechanism for CR-mediated longevity, but they can also directly impact mammalian metabolism as part of the natural gut flora. Here, we discuss the contributions of microorganisms to our knowledge of CR and longevity at the level of both the cell and the organism

    Genome-Wide Screen in Saccharomyces cerevisiae Identifies Vacuolar Protein Sorting, Autophagy, Biosynthetic, and tRNA Methylation Genes Involved in Life Span Regulation

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    The study of the chronological life span of Saccharomyces cerevisiae, which measures the survival of populations of non-dividing yeast, has resulted in the identification of homologous genes and pathways that promote aging in organisms ranging from yeast to mammals. Using a competitive genome-wide approach, we performed a screen of a complete set of approximately 4,800 viable deletion mutants to identify genes that either increase or decrease chronological life span. Half of the putative short-/long-lived mutants retested from the primary screen were confirmed, demonstrating the utility of our approach. Deletion of genes involved in vacuolar protein sorting, autophagy, and mitochondrial function shortened life span, confirming that respiration and degradation processes are essential for long-term survival. Among the genes whose deletion significantly extended life span are ACB1, CKA2, and TRM9, implicated in fatty acid transport and biosynthesis, cell signaling, and tRNA methylation, respectively. Deletion of these genes conferred heat-shock resistance, supporting the link between life span extension and cellular protection observed in several model organisms. The high degree of conservation of these novel yeast longevity determinants in other species raises the possibility that their role in senescence might be conserved

    School Effects on the Wellbeing of Children and Adolescents

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    Well-being is a multidimensional construct, with psychological, physical and social components. As theoretical basis to help understand this concept and how it relates to school, we propose the Self-Determination Theory, which contends that self-determined motivation and personality integration, growth and well-being are dependent on a healthy balance of three innate psychological needs of autonomy, relatedness and competence. Thus, current indicators involve school effects on children’s well-being, in many diverse modalities which have been explored. Some are described in this chapter, mainly: the importance of peer relationships; the benefits of friendship; the effects of schools in conjunction with some forms of family influence; the school climate in terms of safety and physical ecology; the relevance of the teacher input; the school goal structure and the implementation of cooperative learning. All these parameters have an influence in promoting optimal functioning among children and increasing their well-being by meeting the above mentioned needs. The empirical support for the importance of schools indicates significant small effects, which often translate into important real-life effects as it is admitted at present. The conclusion is that schools do make a difference in children’s peer relationships and well-being

    ICAR: endoscopic skull‐base surgery

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