The Asian tiger mosquito, Aedes albopictus (Skuse), is an invasive species with substantial biting activity, high disease vector potential, and a global distribution that continues to expand. New ...Jersey, southern New York, and Pennsylvania are currently the northernmost boundary of established Ae. albopictus populations in the eastern United States. Using positive geographic locations from these areas, we modeled the potential future range expansion of Ae. albopictus in northeastern USA under two climate change scenarios. The land area with environmental conditions suitable for Ae. albopictus populations is expected to increase from the current 5% to 16% in the next two decades and to 43%-49% by the end of the century. Presently, about one-third of the total human population of 55 million in northeastern USA reside in urban areas where Ae. albopictus is present. This number is predicted to double to about 60% by the end of the century, encompassing all major urban centers and placing over 30 million people under the threat of dense Ae. albopictus infestations. This mosquito species presents unique challenges to public health agencies and has already strained the resources available to mosquito control programs within its current range. As it continues to expand into areas with fewer resources and limited organized mosquito control, these challenges will be further exacerbated. Anticipating areas of potential establishment, while planning ahead and gathering sufficient resources will be the key for successful public health campaigns. A broad effort in community sanitation and education at all levels of government and the private sector will be required until new control techniques are developed that can be applied efficiently and effectively at reasonable cost to very large areas.
•A review of techniques to gain information about atmospheric dispersion is presented.•Optimisation- and Bayesian inference-based estimation methods are summarised.•Mobile sensors provide an ideal ...platform for data gathering of atmospheric events.•The current limitations and recommendations for future research is discussed.
Understanding atmospheric transport and dispersal events has an important role in a range of scenarios. Of particular importance is aiding in emergency response after an intentional or accidental chemical, biological or radiological (CBR) release. In the event of a CBR release, it is desirable to know the current and future spatial extent of the contaminant as well as its location in order to aid decision makers in emergency response. Many dispersion phenomena may be opaque or clear, thus monitoring them using visual methods will be difficult or impossible. In these scenarios, relevant concentration sensors are required to detect the substance where they can form a static network on the ground or be placed upon mobile platforms. This paper presents a review of techniques used to gain information about atmospheric dispersion events using static or mobile sensors. The review is concluded with a discussion on the current limitations of the state of the art and recommendations for future research.
Aim Interest in species distribution models (SDMs) and related niche studies has increased dramatically in recent years, with several books and reviews being prepared since 2000. The earliest SDM ...studies are dealt with only briefly even in the books. Consequently, many researchers are unaware of when the first SDM software package (bioclim) was developed and how a broad range of applications using the package was explored within the first 8 years following its release. The purpose of this study is to clarify these early developments and initial applications, as well as to highlight bioclim's continuing relevance to current studies. Location Mainly Australia and New Zealand, but also some global applications. Methods We outline the development of the bioclim package, early applications (1984–1991) and its current relevance. Results bioclim was the first SDM package to be widely used. Early applications explored many of the possible uses of SDMs in conservation biogeography, such as quantifying the environmental niche of species, identifying areas where a species might be invasive, assisting conservation planning and assessing the likely impacts of climate change on species distributions. Main conclusions Understanding this pioneering work is worthwhile as bioclim was for many years one of the leading SDM packages and remains widely used. Climate interpolation methods developed for bioclim were used to create the WorldClim database, the most common source of climate data for SDM studies, and bioclim variables are used in about 76% of recent published MaxEnt analyses of terrestrial ecosystems. Also, some of the bioclim studies from the late 1980s, such as measuring niche (both realized and fundamental) and assessing possible impacts of climate change, are still highly relevant to key conservation biogeography issues.
Finding the location and strength of an unknown hazardous release is of paramount importance in emergency response and environmental monitoring; thus, it has been an active research area for several ...years known as source term estimation (STE). This paper presents a joint Bayesian estimation and planning algorithm to guide a mobile robot to collect informative measurements, allowing the source parameters to be estimated quickly and accurately. The estimation is performed recursively using Bayes' theorem, where uncertainties in the meteorological and dispersion parameters are considered and the intermittent readings from a low-cost gas sensor are addressed by a novel likelihood function. The planning strategy is designed to maximize the expected utility function based on the estimated information gain of the source parameters. Subsequently, this paper presents the first experimental result of such a system in turbulent, diffusive conditions, in which a ground robot equipped with the low-cost gas sensor responds to the hazardous source simulated by incense sticks. The experimental results demonstrate the effectiveness of the proposed estimation and search algorithm for STE based on the mobile robot and the low-cost sensor.
There is concern in Australia that droughts substantially increase the incidence of suicide in rural populations, particularly among male farmers and their families. We investigated this possibility ...for the state of New South Wales (NSW), Australia between 1970 and 2007, analyzing data on suicides with a previously established climatic drought index. Using a generalized additive model that controlled for season, region, and long-term suicide trends, we found an increased relative risk of suicide of 15% (95% confidence interval, 8%–22%) for rural males aged 30–49 y when the drought index rose from the first quartile to the third quartile. In contrast, the risk of suicide for rural females aged >30 y declined with increased values of the drought index. We also observed an increased risk of suicide in spring and early summer. In addition there was a smaller association during unusually warm months at any time of year. The spring suicide increase is well documented in nontropical locations, although its cause is unknown. The possible increased risk of suicide during drought in rural Australia warrants public health focus and concern, as does the annual, predictable increase seen each spring and early summer. Suicide is a complex phenomenon with many interacting social, environmental, and biological causal factors. The relationship between drought and suicide is best understood using a holistic framework. Climate change projections suggest increased frequency and severity of droughts in NSW, accompanied and exacerbated by rising temperatures. Elucidating the relationships between drought and mental health will help facilitate adaptation to climate change.
highlights•Cognitive search and source term estimation strategy for a mobile sensor is proposed.•Maximum entropy sampling principles are adopted to maximise the information gain.•The proposed ...Entrotaxis strategy shows faster search time than the existing methods.
This paper proposes a strategy for performing an efficient autonomous search to find an emitting source of sporadic cues of noisy information. We focus on the search for a source of unknown strength, releasing particles into the atmosphere where turbulence can cause irregular gradients and intermittent patches of sensory cues. Bayesian inference, implemented via the sequential Monte Carlo method, is used to update posterior probability distributions of the source location and strength in response to sensor measurements. Posterior sampling is then used to approximate a reward function, leading to the manoeuvre to where the entropy of the predictive distribution is the greatest. As it is developed based on the maximum entropy sampling principle, the proposed framework is termed as Entrotaxis. We compare the performance and search behaviour of Entrotaxis with the popular Infotaxis algorithm, for searching in sparse and turbulent conditions where typical gradient-based approaches become inefficient or fail. The algorithms are assessed via Monte Carlo simulations with simulated data and an experimental dataset. Whilst outperforming the Infotaxis algorithm in most of our simulated scenarios, by achieving a faster mean search time, the proposed strategy is also more computationally efficient during the decision making process.
Cohort study.
To investigate and critique different methods for aerobic exercise intensity prescription in adults with spinal cord injury (SCI).
University laboratory in Loughborough, UK.
Trained ...athletes were split into those with paraplegia (PARA; n = 47), tetraplegia (TETRA; n = 20) or alternate health condition (NON-SCI; n = 67). Participants completed a submaximal step test with 3 min stages, followed by graded exercise test to exhaustion. Handcycling, arm crank ergometry or wheelchair propulsion were performed depending on the sport of the participant. Oxygen uptake (V̇O
), heart rate (HR), blood lactate concentration (BLa) and ratings of perceived exertion (RPE) on Borg's RPE scale were measured throughout. Lactate thresholds were identified according to log-V̇O
plotted against log-BLa (LT
) and 1.5 mmol L
greater than LT
(LT
). These were used to demarcate moderate (<LT
), heavy (>LT
, < LT
) and severe (>LT
) exercise intensity domains.
Associations between percentage of peak V̇O
(%V̇O
) and HR (%HR
) with RPE differed between PARA and TETRA. At LT
and LT
, %V̇O
and %HR
were significantly greater in TETRA compared to PARA and NON-SCI (P < 0.05). The variation in %V̇O
and %HR
at lactate thresholds resulted in large variability in the domain distribution at fixed %V̇O
and %HR
.
Fixed %V̇O
and %HR
should not be used for aerobic exercise intensity prescription in adults with SCI as the method does not lead to uniform exercise intensity domain distribution.
ANUCLIM (Xu and Hutchinson, 2011) is a unique software package used to support the spatial modelling and mapping of environmental and natural resources. It has been extensively employed for ...scientific research, teaching and policy making across study areas at various spatial scales. The package enables users to readily interrogate estimated values, in point and grid form, of monthly, seasonal and annual mean climate variables from supplied elevation dependent monthly mean climate surfaces and an underlying digital elevation model (DEM). The climate surfaces have been derived by the ANUSPLIN package (Hutchinson, 2004) and support interrogation at sub-kilometre scale. A key strength of the ANUCLIM package is its ability to generate bioclimatic profiles from known species locations to predict and map species distributions, in current, projected future and past climates. It can also generate a comprehensive set of climate parameters and growth indices for modelling growth of crops and plants. The package currently has four programs, MTHCLIM, BIOCLIM, BIOMAP and GROCLIM. MTHCLIM is used to obtain estimates of monthly mean climate variables from supplied climate surfaces at specified points or grids. BIOCLIM, in conjunction with BIOMAP, is a bioclimatic prediction system based on the bioclimatic envelope method devised by Nix (1986). GROCLIM is used to generate plant growth indices based on a simplified model of plant growth response to light, thermal and water regimes (Nix, 1981). The latest version of ANUCLIM, Version 6.1, incorporates substantial upgrades. In particular, the package now allows each of its four component programs to systematically incorporate the impacts of projected climate change. These projected climate changes can be provided either as simple constants, or more commonly, as grids of broad scale changes as obtained from outputs of General Circulation Models (GCMs) under various emission scenarios. For Australia, such grids can be obtained from the OzClim website of CSIRO (2007). This enables the systematic investigation of the impacts of projected climate change on socio-environmental systems.
► ANUCLIM has been extensively employed for research, teaching and policy making. ► We substantially upgraded the ANUCLIM package to Version 6.1. ► ANUCLIM can now systematically incorporate projected climate change grids. ► ANUCLIM Version 6.1 is more robust and faster. ► ANUCLIM Version 6.1 has been used successfully in recent projects.
Multiple sclerosis (MS) has entered an era of immunomodulatory drug treatment, the impact of which on long-term disease progression remains controversial. The increasing use of these therapies has ...intensified our need to understand the true natural history of MS. The MS community is poised to establish whether the immunomodulatory drugs exhibit long-term benefits, with a suitable untreated natural history cohort likely the most practical and ethical comparator group. Thus, a thorough understanding of the natural history of MS is fundamental. In this review, we highlight recent advances in MS natural history over the last 5 years, with a focus on long-term population-based cohorts and factors associated with disease progression. Survival in MS has increased and longer times to irreversible disability have been reported in contemporary studies, indicating a slower accumulation of disability. Wide variation in the MS disease trajectory is evident within and between natural history studies, reflecting both methodologic considerations related to data collection and heterogeneity of disease activity. Recent publications have indicated that a younger age at disease onset is no longer indicative of a favorable outcome and further evidence supports the dissociation between relapses and long-term disability, although windows of opportunity may exist for some patients. We are now perhaps faced with our last chance to examine the true natural history of MS, so whether the reader is a practicing physician, health care provider, or researcher, or engaged in the pharmaceutical industry or in clinical trial design, recent advances in our understanding of the natural history of MS are of key significance.
Evidence exists that tree mortality is accelerating in some regions of the tropics
, with profound consequences for the future of the tropical carbon sink and the global anthropogenic carbon budget ...left to limit peak global warming below 2 °C. However, the mechanisms that may be driving such mortality changes and whether particular species are especially vulnerable remain unclear
. Here we analyse a 49-year record of tree dynamics from 24 old-growth forest plots encompassing a broad climatic gradient across the Australian moist tropics and find that annual tree mortality risk has, on average, doubled across all plots and species over the last 35 years, indicating a potential halving in life expectancy and carbon residence time. Associated losses in biomass were not offset by gains from growth and recruitment. Plots in less moist local climates presented higher average mortality risk, but local mean climate did not predict the pace of temporal increase in mortality risk. Species varied in the trajectories of their mortality risk, with the highest average risk found nearer to the upper end of the atmospheric vapour pressure deficit niches of species. A long-term increase in vapour pressure deficit was evident across the region, suggesting that thresholds involving atmospheric water stress, driven by global warming, may be a primary cause of increasing tree mortality in moist tropical forests.
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