2,596 research outputs found

    No preference in female sika deer for conspecific over heterospecific male sexual calls in a mate choice context

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    Mating signals can be used both in contexts of species recognition and mate quality assessment. This study examines species recognition abilities in oestrous females presented with male mating calls from both conspecifics and closely related allopatric heterospecifics. Red deer and sika deer are naturally allopatric polygynous species capable of hybridization during sympatry. Male mating calls are sexually selected and differ greatly between species. Previous work indicated that most but not all oestrous red deer hinds prefer male mating calls from conspecifics over heterospecific sika deer. Using two-speaker playback experiments, we extend this examination by measuring the preference responses of oestrous sika deer hinds to these stimuli. We predicted that oestrous sika deer hinds will show little flexibility in behavioural responses and prefer conspecific calls over heterospecific calls, similar to those of red deer hinds. In contrast, sika deer hinds showed high levels of flexibility and no difference in overall preference behaviours, suggesting that vocal behaviour does not provide a solid barrier to hybridization in this species. The asymmetry in heterospecific preference responses between these species is discussed in relation to possible causation and hybridization patterns observed in free-ranging populations

    ADAR enzyme and miRNA story: A nucleotide that can make the difference

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    Adenosine deaminase acting on RNA (ADAR) enzymes convert adenosine (A) to inosine (I) in double-stranded (ds) RNAs. Since Inosine is read as Guanosine, the biological consequence of ADAR enzyme activity is an A/G conversion within RNA molecules. A-to-I editing events can occur on both coding and non-coding RNAs, including microRNAs (miRNAs), which are small regulatory RNAs of ~20-23 nucleotides that regulate several cell processes by annealing to target mRNAs and inhibiting their translation. Both miRNA precursors and mature miRNAs undergo A-to-I RNA editing, affecting the miRNA maturation process and activity. ADARs can also edit 3' UTR of mRNAs, further increasing the interplay between mRNA targets and miRNAs. In this review, we provide a general overview of the ADAR enzymes and their mechanisms of action as well as miRNA processing and function. We then review the more recent findings about the impact of ADAR-mediated activity on the miRNA pathway in terms of biogenesis, target recognition, and gene expression regulation

    How I treat myelodysplastic syndromes of childhood

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    Pediatric myelodysplastic syndromes (MDSs) are a heterogeneous group of clonal disorders with an annual incidence of 1 to 4 cases per million, accounting for less than 5% of childhood hematologic malignancies. MDSs in children often occur in the context of inherited bone marrow failure syndromes, which represent a peculiarity of myelodysplasia diagnosed in pediatric patients. Moreover, germ line syndromes predisposing individuals to develop MDS or acute myeloid leukemia have recently been identified, such as those caused by mutations in GATA2, ETV6, SRP72, and SAMD9/SAMD9-L. Refractory cytopenia of childhood (RCC) is the most frequent pediatric MDS variant, and it has specific histopathologic features. Allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of choice for many children with MDSs and is routinely offered to all patients with MDS with excess of blasts, to those with MDS secondary to previously administered chemoradiotherapy, and to those with RCC associated with monosomy 7, complex karyotype, severe neutropenia, or transfusion dependence. Immune-suppressive therapy may be a treatment option for RCC patients with hypocellular bone marrow and the absence of monosomy 7 or a complex karyotype, although the response rate is lower than that observed in severe aplastic anemia, and a relevant proportion of thesepatients will subsequently need HSCT for either nonresponse or relapse

    Do red deer hinds prefer stags that produce harsh roars in mate choice contexts?

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    Red deer stags give two types of roars during the breeding season, termed ‘common’ and ‘harsh’ roars. This study tested the hypothesis that the characteristic spectro-temporal structure of male harsh roars functions to directly attract females towards male callers during the breeding season. The results show that oestrous hinds look for longer towards speakers broadcasting sequences containing harsh roars, but do not preferentially approach or spend more time in close proximity to speakers broadcasting harsh roars over those broadcasting only common roars. While these observations confirm that the specific acoustic structure of male harsh roars functions to draw the attention of hinds, they are not consistent with the notion that these calls have an immediate impact on mate choice decisions by stimulating oestrous hinds to move towards male callers. Consequently, we suggest that intersexual selection through female mate choice is unlikely to be a major factor driving the evolution of male red deer harsh roars

    Impacts of forestation on water and soils in the Andes: What do we know?

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    POLICY BRIEF: This brief summarizes the findings of a systematic review on the impacts of forestation on water and soils in the Andes (detailed in Bonnesoeur et al., 2019). For each finding, we report the confidence level in the evidence found in the literature reviewed. Forestation impacts on water supply, hydrological regulation and soil erosion. The results of the synthesis also helped identify research gaps, which are described at the end

    Modularisation as enabler of circular economy in energy infrastructure

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    Existing energy infrastructure have a technical and/or economic lifecycle predetermined by the lifetime of certain components. In energy infrastructure, the residual lifetime of civil structure or other components with a longer life is usually wasted. Modular energy infrastructure can be reconfigurable decoupling the life of the infrastructure from their modules, and extending module and/or infrastructure lifecycle. Modularisation could become a cornerstone to enable circular economy (CE) and enhanced sustainability. Remarkably, despite the growing interest among policymakers, practitioners and academics in both CE and modularisation, there is a lack of knowledge about the link between CE and modularisation in energy infrastructure. Through a Systematic Literature Review, this paper derives the gap in knowledge regarding the link between CE and modularisation in energy infrastructure. This link is then investigated in other sectors identifying relevant implications such as reduction of construction waste and achievement of the closed-loop material cycle. Furthermore, the case of Yamal Liquefied Natural Gas project is used to compare and contrast two perspectives: “Traditional modularisation” and “Modular CE”. Lastly, the paper discusses existing policies, provides policy recommendations to foster “Modular CE” in energy infrastructure and suggests a research agenda

    Looking back to see the future: building nuclear power plants in Europe

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    The so-called ‘nuclear renaissance’ in Europe is promulgated by the execution of two large engineering projects involving the construction of two European Pressurized Reactors (EPRs) in Flamanville, France and Olkiluoto in Finland. As both projects have faced budget overruns and delays, this paper analyses their governance and history to derive lessons useful for the construction of future projects. Analysis indicates that the reasons for these poor outcomes are: overoptimistic estimations, first-of-a-kind (FOAK) issues and undervaluation of regulation requirements. These pitfalls have the potential to impact on many other engineering construction projects and highlight fruitful areas of further research into project performance

    Economics and finance of Small Modular Reactors: A systematic review and research agenda

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    The interest toward Small Modular nuclear Reactors (SMRs) is growing, and the economic competitiveness of SMRs versus large reactors is a key topic. Leveraging a systematic literature review, this paper firstly provides an overview of “what we know” and “what we do not know” about the economics and finance of SMRs. Secondly, the paper develops a research agenda. Several documents discuss the economics of SMRs, highlighting how the size is not the only factor to consider in the comparison; remarkably, other factors (co-siting economies, modularisation, modularity, construction time, etc.) are relevant. The vast majority of the literature focuses on economic and financial performance indicators (e.g. Levelized Cost of Electricity, Net Present Value, and Internal Rate of Return) and SMR capital cost. Remarkably, very few documents deal with operating and decommissioning costs or take a programme (and its financing) rather than a “single project/plant/site” perspective. Furthermore, there is a gap in knowledge about the cost-benefit analysis of the “modular construction” and SMR decommissioning

    A framework for the selection of the right nuclear power plant

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    Civil nuclear reactors are used for the production of electrical energy. In the nuclear industry vendors propose several nuclear reactor designs with a size from 35–45 MWe up to 1600–1700 MWe. The choice of the right design is a multidimensional problem since a utility has to include not only financial factors as levelised cost of electricity (LCOE) and internal rate of return (IRR), but also the so called “external factors” like the required spinning reserve, the impact on local industry and the social acceptability. Therefore it is necessary to balance advantages and disadvantages of each design during the entire life cycle of the plant, usually 40–60 years. In the scientific literature there are several techniques for solving this multidimensional problem. Unfortunately it does not seem possible to apply these methodologies as they are, since the problem is too complex and it is difficult to provide consistent and trustworthy expert judgments. This paper fills the gap, proposing a two-step framework to choosing the best nuclear reactor at the pre-feasibility study phase. The paper shows in detail how to use the methodology, comparing the choice of a small-medium reactor (SMR) with a large reactor (LR), characterised, according to the International Atomic Energy Agency (2006), by an electrical output respectively lower and higher than 700 MWe
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