3,442 research outputs found
Defining Landscape Resistance Values in Least-Cost Connectivity Models for the Invasive Grey Squirrel: A Comparison of Approaches Using Expert-Opinion and Habitat Suitability Modelling
Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM) in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a leastcost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a leastcost approach to mapping ecological networks.This project was funded by the Forestry Commission GB and the National School of Forestry at the University of Cumbria. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Working Together: Volume 1. Secondary analysis of the Labour Force Survey to map the numbers and characteristics of the occupations working within Social Care, Childcare, Nursing and Education
Using GPS telemetry to validate least-cost modeling of gray squirrel ( Sciurus carolinensis) movement within a fragmented landscape
In Britain, the population of native red squirrels Sciurus vulgaris has suffered population declines and local extinctions. Interspecific resource competition and disease spread by the invasive gray squirrel Sciurus carolinensis are the main factors behind the decline. Gray squirrels have adapted to the British landscape so efficiently that they are widely distributed. Knowledge on how gray squirrels are using the landscape matrix and being able to predict their movements will aid management. This study is the first to use global positioning system (GPS) collars on wild gray squirrels to accurately record movements and land cover use within the landscape matrix. This data were used to validate Geographical Information System (GIS) least-cost model predictions of movements and provided much needed information on gray squirrel movement pathways and network use. Buffered least-cost paths and least-cost corridors provide predictions of the most probable movements through the landscape and are seen to perform better than the more expansive least-cost networks which include all possible movements. Applying the knowledge and methodologies gained to current gray squirrel expansion areas, such as Scotland and in Italy, will aid in the prediction of potential movement areas and therefore management of the invasive gray squirrel. The methodologies presented in this study could potentially be used in any landscape and on numerous species
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The non-receptor tyrosine kinase ACK: regulatory mechanisms, signalling pathways and opportunities for attACKing cancer
Activated Cdc42-associated kinase or ACK, is a non-receptor tyrosine kinase and an effector protein for the small G protein Cdc42. A substantial body of evidence has accumulated in the past few years heavily implicating ACK as a driver of oncogenic processes. Concomitantly, more is also being revealed
regarding the signalling pathways involving ACK and molecular details of its
modes of action. Some details are also available regarding the regulatory
mechanisms of this kinase, including activation and regulation of its catalytic
activity, however a full understanding of these aspects remains elusive. This
review considers the current knowledge base concerning ACK and
summarises efforts and future prospects to target ACK therapeutically in
cancer.MR
Addressing environmental and atmospheric challenges for capturing high-precision thermal infrared data in the field of astro-ecology
Using thermal infrared detectors mounted on drones, and applying techniques
from astrophysics, we hope to support the field of conservation ecology by
creating an automated pipeline for the detection and identification of certain
endangered species and poachers from thermal infrared data. We test part of our
system by attempting to detect simulated poachers in the field. Whilst we find
that we can detect humans hiding in the field in some types of terrain, we also
find several environmental factors that prevent accurate detection, such as
ambient heat from the ground, absorption of infrared emission by the
atmosphere, obscuring vegetation and spurious sources from the terrain. We
discuss the effect of these issues, and potential solutions which will be
required for our future vision for a fully automated drone-based global
conservation monitoring system.Comment: Published in Proceedings of SPIE Astronomical Telescopes and
Instrumentation 2018. 8 pages, 3 figure
Screen time is associated with adiposity and insulin resistance in children
Higher screen time is associated with type 2 diabetes (T2D) risk in adults, but the association with T2D risk markers in children is unclear. We examined associations between self-reported screen time and T2D risk markers in children. Survey of 4495 children aged 9-10 years who had fasting cardiometabolic risk marker assessments, anthropometry measurements and reported daily screen time; objective physical activity was measured in a subset of 2031 children. Compared with an hour or less screen time daily, those reporting screen time over 3 hours had higher ponderal index (1.9%, 95% CI 0.5% to 3.4%), skinfold thickness (4.5%, 0.2% to 8.8%), fat mass index (3.3%, 0.0% to 6.7%), leptin (9.2%, 1.1% to 18.0%) and insulin resistance (10.5%, 4.9% to 16.4%); associations with glucose, HbA1c, physical activity and cardiovascular risk markers were weak or absent. Associations with insulin resistance remained after adjustment for adiposity, socioeconomic markers and physical activity. Strong graded associations between screen time, adiposity and insulin resistance suggest that reducing screen time could facilitate early T2D prevention. While these observations are of considerable public health interest, evidence from randomised controlled trials is needed to suggest causality. [Abstract copyright: Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Cluster observations of the midaltitude cusp under strong northward interplanetary magnetic field
We report on a multispacecraft cusp observation lasting more than 100 min. We
determine the cusp boundary motion and reveal the effect on the cusp size of the
interplanetary magnetic field (IMF) changing from southward to northward. The cusp
shrinks at the beginning of the IMF rotation and it reexpands at the rate of 0.40°
invariant latitude per hour under stable northward IMF. On the basis of plasma signatures
inside the cusp, such as counterstreaming electrons with balanced fluxes, we propose
that pulsed dual lobe reconnection operates during the time of interest. SC1 and
SC4 observations suggest a long-term regular periodicity of the pulsed dual reconnection,
which we estimate to be ~1–5 min. Further, the distances from the spacecraft to
the reconnection site are estimated on the basis of observations from three satellites. The
distance determined using SC1 and SC4 observations is ~15 RE and that determined
from SC3 data is ~8 RE. The large-scale speed of the reconnection site sunward motion is
~16 km s-1. We observe also a fast motion of the reconnection site by SC1, which
provides new information about the transitional phase after the IMF rotation. Finally, a
statistical study of the dependency of plasma convection inside the cusp on the IMF clock
angle is performed. The relationship between the cusp stagnation, the dual lobe
reconnection process, and the IMF clock angle is discussed
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Parents’ experiences of introducing toddlers to fruits and vegetables through repeated exposure, with and without prior visual familiarization to foods: evidence from daily diaries
While repeated exposure is an established method for inducing food acceptance in young children, little is known about parents’ experiences of repeatedly offering new or disliked foods at home. In this study, parents kept structured diary records during a 15-day period in which they offered their 2-year-old child daily tastes of one fruit and one vegetable. We explored how children’s acceptance of foods (measured in terms of willingness to taste, liking and intake) and the ease and enjoyment of the process for parents changed from the early (days 1-5) to middle (days 6-10) to later (days 11-15) phases of exposure. In addition, we explored whether prior visual familiarization to foods affected children’s behavior and/or parents’ experiences during exposure. Families were randomly assigned to look at a picture book about one to-be-exposed food for the two weeks prior to the exposure phase (‘fruit book’ and ‘vegetable book’ groups) or to a control group, who did not receive a book. Measures obtained from parents’ diary records revealed increases in willingness to taste and intake of vegetables and increased liking of both fruits and vegetables with greater exposure. Prior visual familiarization to vegetables further boosted children’s willingness to taste and liking of vegetables, and the ease and enjoyment of introducing these for parents. Children’s acceptance of foods and parents’ positivity during exposure predicted children’s liking and intake of foods 3 months later. Results confirm the potential for vegetable picture books to support parents in engaging with repeated exposure regimes and in successfully introducing vegetables into toddlers’ diets
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