210 research outputs found

    Earth’s Natural Heritage’

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    For professionals tasked with managing protected areas, it is imperative that they have a broad understanding of the intrinsic natural values of our planet. In this chapter we provide this overview. We describe some of Earth’s natural processes, and its exceptional geodiversity and biodiversity. Then we briefly introduce, at a global scale, the impacts that humans are having on Earth’s natural heritage early in the 21st Century. This helps to emphasise why protected areas of all types, including government, non-government, private, indigenous and community conserved areas (ICCAs), are needed and why the efforts of each individual manager or ranger working in support of their local protected area or protected area system is so critical. Fundamentally it is the sum total of these individual and local conservation efforts that is contributing to the retention of life on Earth.JRC.H.5-Land Resources Managemen

    Resilience and young people's brain structure, function and connectivity: A systematic review

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    Although negative early life experiences are associated with an increased risk of developing psychopathology, some individuals exposed to childhood adversity demonstrate psychological resilience. Little is known about the neural correlates of resilience, especially in young people. To address this gap, we conducted a systematic review of neuroimaging studies of resilience in youth. The PubMed, Web of Science, Scopus, and PsycINFO databases were searched; 5,482 studies were identified. Following title/abstract screening, and full reading of the remaining articles, 22 studies based on 19 unique datasets were included. We found preliminary evidence that resilience is associated with structural, functional, and connectivity differences in young people, as assessed using structural and functional MRI and diffusion tensor imaging methods. Despite heterogeneity in definitions/assessment of resilience and a limited number of studies, the neuroimaging literature suggests some convergence across modalities regarding brain regions linked to resilience (especially the prefrontal cortex). Future studies would benefit from adopting longitudinal designs, broader conceptualisations of resilience that capture the impact of adversity exposure, and a dimensional approach to psychopathology

    An ecophysiological study of the effects of changes in salinity and temperature on the distribution of Macrobrachium Petersi (Hilgendorf) in the Keiskamma river and estuary

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    Summary: The distribution of adult, juvenile, post larval and larval Macrobrachium petersi (Hilgendorf) was studied in relation to temperature and salinity in the Keiskamma river and estuary from May 1979 to May 1981. M. petersi is a subtropical species, which confined activity of all stages in the field to the summer months. Variable freshwater discharge and tidal effects determined the salinity and temperature profiles in the middle and upper reaches of the Keiskamma estuary. Thus, a dry 1979/80 summer and a wet 1980/81 summer markedly influenced the abundance and distribution of adult M. petersi in the river and estuary respectively. Adult M. petersi migrate to the estuary under flooding conditions and upstream in response to elevated salinities. Although M. petersi has nine larval stages only a preponderance of stage I were caught in the field. These portray a distinct nocturnal and diurnal distribution pattern which is influenced by salinity, especially under stratified conditions. After flooding the larvae show an affinity for salt front regions and reach these by remaining in the water column on the ebbing tide. A substantial drop in abundance downstream from the salt front suggests that the larvae loose their planktonic phase which is an effective retention mechanism, and confines larval development to the middle and upper reaches of the estuary. Post larvae were caught towards the end of the 1981 breeding season which indicates that complete larval development takes place in the estuary. A post larval migration to freshwater, which reaches a peak in February and March, was monitored. Thus both the freshwater and estuarine environments form an inseparable link in the life cycle of M. petersi. The distribution of stage I larvae in the Keiskamma estuary suggested that salinity played a role in development. The fact that other larval stages were not found emphasised the necessity for a quantitative laboratory investigation to determine the importance of salinity in the developmental history of M. petersi larvae and post larvae. However, the modifying influence of temperature could not be ignored so a multivariable approach was adopted. This, together with a surface response technique, aided the interpretation of the effect of a variety of combinations of salinity and temperature on ecdysis to stage II, larval survival and requirements for metamorphosis to post larvae. It was estimated that the minimum salinity requirement for complete larval development, within a temperature range from 18 to 30⁰C was 8%₀, although ecdysis to stage II and metamorphosis to post larvae could occur in salinities less than this value. Despite the euryhalinity of the larvae, the behaviour of adult M. petersi to an increase in salinity and the affinity of stage I larvae to salt front regions restricted development to the upper reaches of the estuary. This is discussed as an adaptation which not only ensures retention within the estuary but favours recruitment to the adult population in freshwater. The osmoregulatory patterns of larval, post larval, juvenile and adult M. petersi correlated with their distribution. These were approximated by a cubic polynomial which enabled the different patterns to be compared. The larval stages investigated (I, II, V & IX) displayed a remarkable capacity to regulate which was strongest in stage I as these could regulate in both freshwater and 35%₀. The ability to regulate in freshwater was lost hereafter but regained in the post larvae, which also regulated in 35%₀. Juveniles (caught at the ebb and flow) displayed a similar regulatory pattern to the adults and "hyposmoconformed" in salinities beyond the isosmotic point as the need to regulate in 35%₀ was no longer necessary. The osmoregulatory capacity of M. petersi larvae in relation to other decapod larvae is discussed. Marine transport of the euryhaline larval and post larval stages accounts for the distribution of M. petersi along the South African coastline. However, south of 31°S latitude the sea-surface temperature decreases abruptly. This region coincides with the southern limit of the distribution of M. petersi. Although larval M. petersi can tolerate high salinity (35%₀) in combination with low temperature, the post larvae cannot, which is likely to account for their restricted southern distribution. The genus Macrobrachium are in the process of invading freshwater. The possible course that this might have taken has been discussed in the light of available evidence as well as the findings of this study

    New politics and old party persistence : party adaptation in Australia, Britain, and the United States

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    Over the past three decades the notion that western party-systems remain frozen has been challenged by the apparent onset of post-industrial trends which threaten the support base of old political parties. In particular, scholars rejecting the freezing proposition have identified a rise in aggregate electoral volatility, a decline in group voting loyalties and the emergence of a New Politics. This study argues that the party systems of Australia, Britain and the United States remain characterised by aggregate electoral stability, despite a weakening in the extent to which electoral choice is structured by long-term political predispositions. In addition long-term electoral stability has occurred despite considerable social and attitudinal changes with the potential to alter significantly the underlying balance of party support. Through the use of national election studies collected between the mid 1960s and early 1990s in each country, it is argued that the adaptive strategies of political parties represent an intervening variable in the extent to which societal change is translated into electoral change. The study concludes that the so-called dealigning trends, such as the decline of group voting loyalties and the emergence of a New Politics, are an outcome, in part, of the strategic decisionmaking of old party leaders seeking to preserve their party's long-term persistence. The extent to which parties succeed or fail is not a system determined factor, but rather an outcome of the ability of a party organisation to adapt to societal changes which threaten its traditional support base

    Monitoring health in smart homes using simple sensors.

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    We consider use of an ambient sensor network, installed in Smart Homes, to identify low level events taking place which can then be analysed to generate a resident's profile of activities of daily living (ADLs). These ADL profiles are compared to both the resident's typical profile and to known 'risky' profiles to support evidence-based interventions. Human activity recognition to identify ADLs from sensor data is a key challenge, a windowbased representation is compared on four existing datasets. We find that windowing works well, giving consistent performance. We also introduce FITsense, which is building a Smart Home environment to specifically identify increased risk of falls to allow interventions before falls occurs

    Representing temporal dependencies in human activity recognition.

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    Smart Homes offer the opportunity to perform continuous, long-term behavioural and vitals monitoring of residents, which may be employed to aid diagnosis and management of chronic conditions without placing additional strain on health services. A profile of the resident’s behaviour can be produced from sensor data, and then compared over time. Activity Recognition is a primary challenge for profile generation, however many of the approaches adopted fail to take full advantage of the inherent temporal dependencies that exist in the activities taking place. Long Short Term Memory (LSTM) is a form of recurrent neural network that uses previously learned examples to inform classification decisions. In this paper we present a variety of approaches to human activity recognition using LSTMs and consider the temporal dependencies that exist in binary ambient sensor data in order to produce case-based representations. These LSTM approaches are compared to the performance of a selection of baseline classification algorithms on several real world datasets. In general, it was found that accuracy in LSTMs improved as additional temporal information was presented to the classifier

    Representing temporal dependencies in smart home activity recognition for health monitoring.

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    Long term health conditions, such as fall risk, are traditionally diagnosed through testing performed in hospital environments. Smart Homes offer the opportunity to perform continuous, long-term behavioural and vitals monitoring of residents, which may be employed to aid diagnosis and management of chronic conditions without placing additional strain on health services. A profile of the resident’s behaviour can be produced from sensor data, and then compared overtime. Activity Recognition is a primary challenge for profile generation, however many of the approaches adopted fail to take full advantage of the inherent temporal dependencies that exist in the activities taking place. Long Short Term Memory (LSTM) is a form of recurrent neural network that uses previously learned examples to inform classification decisions. In this paper we present a variety of approaches to human activity recognition using LSTMs which consider the temporal dependencies present in the sensor data in order to produce richer representations and improved classification accuracy. The LSTM approaches are compared to the performance of a selection of base line classification algorithms on several real world datasets. In general, it was found that accuracy in LSTMs improved as additional temporal information was presented to the classifier

    TOWARDS PRACTICAL MODELING OF INTEGRAL-ABUTMENT BRIDGES UNDER LONGITUDINAL LOAD

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    Abstract: Bridges with integral or semi-integra

    Soliton bound states in semiconductor disk laser

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    We report what we believe is the first demonstration of a temporal soliton bound state in semiconductor disk laser. The laser was passively mode-locked using a quantum dot based semiconductor saturable absorber mirror (QD-SESAM). Two mode-locking regimes were observed where the laser would emit single or closely spaced double pulses (soliton bound state regime) per cavity round-trip. The pulses in soliton bound state regime were spaced by discrete, fixed time duration. We use a system of delay differential equations to model the dynamics of our device
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