1,156 research outputs found

    Adaptation to climate in widespread eucalypt species

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    AbstractThe long term success of revegetation efforts will depend upon the planted species’ resilience to climate change. Many widespread species grow across a range of climatic conditions and, thus, may possess adaptations that could be utilised to improve climate resilience of restored ecosystems. Species can achieve a widespread distribution via two main mechanisms; (1) by diverging into a series of specialised populations, or (2) through high phenotypic plasticity. The extent to which populations are specialised or plastic in response to climate will determine the seed-sourcing strategy required for optimal restoration outcomes under a changing climate. We examined genetic divergence and phenotypic plasticity in two widespread Eucalyptus species (E. tricarpa in southeastern Australia, E. salubris in southwestern Australia), to determine the nature of adaptation to climate in these species, and whether genomic screening might be a useful tool to assess climate adaptation.We examined nine populations of each species across climate gradients and, for E. tricarpa, trees originating from the same populations were also studied in two common garden field trials. We characterised responses in functional traits relevant to climate adaptation, including leaf size, thickness, tissue density, and carbon isotope ratio (δ13C). Genetic variation was assessed with genome scans using DArTseq markers, and ‘outlier markers’ were identified as being linked to regions of the genome that are potentially under selection.Evidence of both plastic response and genetic specialisation for climate was found in both species, indicating that widespread eucalypts utilise a combination of both mechanisms for adaptation to spatial variation in climate. The E. tricarpa common garden data suggested high plasticity in most of the measured functional traits, and the extent of plasticity in some traits (e.g. leaf size and thickness) varied among provenances, suggesting genetic variation for plasticity itself. In E. salubris, most functional traits showed little variation across the gradient. However, water use efficiency appeared highly plastic, as determined from the strong correlation between δ13C and recent precipitation (R2 = 0.83). Both species showed spatial partitioning of genetic variation across the gradient, and data for E. salubris revealed two distinct lineages. The genome scans yielded 16,122 DArTseq markers for “Lineage 1” of E. salubris, of which 0.1% were potentially adaptive ‘outlier loci’, and 6,544 markers for E. tricarpa, of which 2.6% were outliers. Canonical Analysis of Principal Coordinates (CAP) analysis showed that the outlier markers were correlated with climatic variables, and some were also strongly correlated with functional traits. An ‘Aridity Index’ was also developed from the CAP analysis that has potential as a tool for environmental planners to use for matching seed sources to target climates.Widespread eucalypts are likely to possess a capacity to respond plastically to a changing climate to some extent, but selection of seed sources to match projected climate changes may confer even greater climate resilience. Further study of the mechanisms of plasticity in response to climate may improve our ability to assess climate adaptation in other species, and to determine optimal strategies for ecosystem restoration and management under climate change

    Error Correcting Codes and the Human Genome.

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    In this work, we study error correcting codes and generalize the concepts with a view toward a novel application in the study of DNA sequences. The author investigates the possibility that an error correcting linear code could be included in the human genome through application and research. The author finds that while it is an accepted hypothesis that it is reasonable that some kind of error correcting code is used in DNA, no one has actually been able to identify one. The author uses the application to illustrate how the subject of coding theory can provide a teaching enrichment activity for undergraduate mathematics

    Enterprise Resource Planning and Organizational Knowledge: Patterns of Convergence and Divergence

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    This paper describes a qualitative research project involving a case study that was analyzed using grounded theory and cognitive mapping. It contributes to a theory that describes the impact of enterprise resource planning (ERP) on organizational knowledge. ERP systems produce effects that make business knowledge become more focused or “convergent” from the perspective of the organization and more wide-ranging or “divergent” from the perspective of the individual. Other important effects include changes to the organization’s core competencies and changes in the risk profile regarding the loss of organizational knowledge

    Factors which could influence the development of adolescent depression

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    An investigation into the prevalence and causative factors of adolescent depression in the greater Johannesburg area was undertaken. Present-day South African socio-economic pressures together with the normal demands and difficulties of adolescence, led to an investigation into which factors were having a bearing on adolescent depression and whether more male than female adolescents were depressed. A literature study was done and major factors, which could potentially influence the development of depression, were identified. The results of the empirical investigation indicated that negative family relations and negative peer relations play a significant role in the development of adolescent depression. Other identified factors did not appear to have a statistically significant bearing on adolescent depression. No significant statistical difference was found between the prevalence or severity of male and female adolescent depression. Educational implications of the findings are discussed and guidelines are given to teachers and parents.Teacher EducationM.Ed. (Guidance and Counselling

    ARE WE ON THE WRONG TRACK AND SO DO MIS CURRICULA NEED TO BE REENGINEERED?

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    Extensive discussions and roundtables done by the panelists with tens of CIOs in recent years suggest that there is increased CIO concern about the depreciation in the perceived importance of MIS in the industry and a need therefore to adapt the curriculum of MIS and its place in the MBA program to what the industry needs. The panel will discuss this issue by first presenting the industry view of the issue based on CIO input and with it the need to reengineer the curriculum accordingly to tune it to what the industry, our clients, needs. The panel will then balance this perspective with a more cautious academic one. Practical steps academia can take will also be discussed

    ICIS 2011 Panel Report: Are We on the Wrong Track and Do MIS Curricula Need to Be Reengineered?

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    The discipline of MIS has been going through extensive soul searching in recent years. Part of that soul searching deals with the question of whether we are teaching our students the right material considering the emerging apparent rift, caused in part by new technologies, between what the industry needs and what we teach. This article summarizes a panel on this topic held at the 32nd meeting of the International Conference on Information Systems (ICIS) in Shanghai 2011. The objective of the panel was to contrast what industry tells us they need and we do not give them, as presented by Gefen and Ragowsky based on several years of CIO roundtables and interviews, with a “balanced head” perspective presented by some of the most respected leaders in our field. The panel attracted an audience of approximately 160 attendees who took an active role in the discussion. Rather surprisingly, disagreements among the panelists were not as pronounced as might have been expected, and the audience mostly supported the antagonist position. We present this summary to our colleagues in MIS in the hope of eliciting a continued discussion on this crucial issue

    Climate-adjusted provenancing: A strategy for climate-resilient ecological restoration

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    Investments in ecological restoration are estimated at $US 2 trillion per annum worldwide and are increasing rapidly (Cunningham, 2008; Williams et al., 2014). These investments are occurring in an environment of accelerated climate change that is projected to continue into the next century, yet they currently take little account of such change. This has significant implications for the long-term success of restoration plantings across millions of hectares, with germplasm used in current restoration efforts potentially poorly-adapted to future climates. New approaches that optimize the climate-resilience of these restoration efforts are thus essential (Breed et al., 2013; Williams et al., 2014; Havens et al., 2015)..

    Daytime site characterisation of La Palma, and its relation to night-time conditions

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    This paper presents preliminary daytime profiles taken using a Wide-Field Shack-Hartmann Sensor at the Swedish Solar Telescope (SST), La Palma. These are contrasted against Stereo-SCIDAR data from corresponding nights to assess the validity of the assumptions currently used for simulating the performances of possible Multi-Conjugate Adaptive Optics (MCAO) systems for future solar telescopes, especially the assumption that the structure of the high altitude turbulence is mostly similar between the day and the night. We find that for our data both the altitude and the strength of the turbulence differ between the day and the night, although more data is required to draw any conclusions about typical behaviour and conditions

    Prenatal maternal stress was not associated with birthweight or gestational age at birth during COVID-19 restrictions in Australia : the BITTOC longitudinal cohort study

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    Background: Various forms of prenatal maternal stress (PNMS) have been reported to increase risk for preterm birth and low birthweight. However, the associations between specific components of stress – namely objective hardship and subjective distress - and birth outcomes are not well understood. Aims: Here, we aimed to determine the relationship between birthweight and gestational age at birth and specific prenatal factors (infant gender and COVID-19 pandemic-related objective hardship, subjective distress, change in diet), and to determine whether effects of hardship are moderated by maternal subjective distress, change in diet, or infant gender. Materials and methods: As part of the Birth in the Time of COVID (BITTOC study), women (N = 2285) who delivered in Australia during the pandemic were recruited online between August 2020 and February 2021. We assessed objective hardship and subjective distress related to the COVID pandemic and restrictions, and birth outcomes through questionnaires that were completed at recruitment and two months post-partum. Analyses included hierarchical multiple regressions. Results: No associations between maternal objective hardship or subjective distress and gestational age at birth or birthweight were identified. Lower birthweight was significantly associated with female gender (adjusted β = 0.083, P < 0.001) and with self-reported improvement in maternal diet (adjusted β = 0.059, P = 0.015). Conclusions: In a socioeconomically advantaged sample, neither objective hardship nor subjective distress related to COVID-19 were associated with birth outcomes. Further research is warranted to understand how other individual factors influence susceptibility to PNMS and how these findings are applicable to women with lower socioeconomic status

    A parameterization of flow separation over subaqueous dunes

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    Flow separation plays a key role in the development of dunes, and modeling the complicated flow behavior inside the flow separation zone requires much computational effort. To make a first step toward modeling dune development at reasonable temporal and spatial scales, a parameterization of the shape of the flow separation zone over two-dimensional dunes is proposed herein, in order to avoid modeling the complex flow inside the flow separation zone. Flow separation behind dunes, with an angle-of-repose slip face, is characterized by a large circulating leeside eddy, where a separation streamline forms the upper boundary of the recirculating eddy. Experimental data of turbulent flow over two-dimensional subaqueous bed forms are used to parameterize this separation streamline. The bed forms have various heights and height to length ratios, and a wide range of flow conditions is analyzed. This paper shows that the shape of the flow separation zone can be approximated by a third-order polynomial as a function of the distance away from the flow separation point. The coefficients of the polynomial can be estimated, independent of flow conditions, on the basis of bed form shape at the flow separation point and a constant angle of the separation streamline at the flow reattachment point. \ud \u
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