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Subglacial sediments have the potential to reveal information about the controls on glacier flow, changes in ice-sheet history and characterise life in those environments. Retrieving sediments from beneath the ice, through hot water drilled access holes at remote field locations, present many challenges. Motivated by the need to minimise weight, corer diameter and simplify assembly and operation, British Antarctic Survey, in collaboration with UWITEC, developed a simple mechanical percussion corer. At depths over 1000 m however, manual operation of the percussion hammer is compromised by the lack of clear operator feedback at the surface. To address this, we present a new auto-release-recovery percussion hammer mechanism that makes coring operations depth independent and improves hammer efficiency. Using a single rope tether for both the corer and hammer operation, this modified percussion corer is relatively simple to operate, easy to maintain, and has successfully operated at a depth of >2130 m.
The Eating Assessment in Toddlers FFQ (EAT FFQ) has been shown to have good reliability and comparative validity for ranking nutrient intakes in young children. With the addition of food items (n 4), we aimed to re-assess the validity of the EAT FFQ and estimate calibration factors in a sub-sample of children (n 97) participating in the Growing Up Milk – Lite (GUMLi) randomised control trial (2015–2017). Participants completed the ninety-nine-item GUMLi EAT FFQ and record-assisted 24-h recalls (24HR) on two occasions. Energy and nutrient intakes were assessed at months 9 and 12 post-randomisation and calibration factors calculated to determine predicted estimates from the GUMLi EAT FFQ. Validity was assessed using Pearson correlation coefficients, weighted kappa (κ) and exact quartile categorisation. Calibration was calculated using linear regression models on 24HR, adjusted for sex and treatment group. Nutrient intakes were significantly correlated between the GUMLi EAT FFQ and 24HR at both time points. Energy-adjusted, de-attenuated Pearson correlations ranged from 0·3 (fibre) to 0·8 (Fe) at 9 months and from 0·3 (Ca) to 0·7 (Fe) at 12 months. Weighted κ for the quartiles ranged from 0·2 (Zn) to 0·6 (Fe) at 9 months and from 0·1 (total fat) to 0·5 (Fe) at 12 months. Exact agreement ranged from 30 to 74 %. Calibration factors predicted up to 56 % of the variation in the 24HR at 9 months and 44 % at 12 months. The GUMLi EAT FFQ remained a useful tool for ranking nutrient intakes with similar estimated validity compared with other FFQ used in children under 2 years.
Life course research embraces the complexity of health and disease development, tackling the extensive interactions between genetics and environment. This interdisciplinary blueprint, or theoretical framework, offers a structure for research ideas and specifies relationships between related factors. Traditionally, methodological approaches attempt to reduce the complexity of these dynamic interactions and decompose health into component parts, ignoring the complex reciprocal interaction of factors that shape health over time. New methods that match the epistemological foundation of the life course framework are needed to fully explore adaptive, multilevel, and reciprocal interactions between individuals and their environment. The focus of this article is to (1) delineate the differences between lifespan and life course research, (2) articulate the importance of complex systems science as a methodological framework in the life course research toolbox to guide our research questions, (3) raise key questions that can be asked within the clinical and translational science domain utilizing this framework, and (4) provide recommendations for life course research implementation, charting the way forward. Recent advances in computational analytics, computer science, and data collection could be used to approximate, measure, and analyze the intertwining and dynamic nature of genetic and environmental factors involved in health development.
Person-centred care is recognized as best practice in dementia care. The purpose of this study was to evaluate the effectiveness of a stakeholder engagement practice change initiative aimed at increasing the provision of person-centred mealtimes in a residential care home (RCH). A single-group, time series design was used to assess the impact of the practice change initiative on mealtime environment across four time periods (pre-intervention, 1-month, 3-month, and 6-month follow-up). Statistically significant improvements were noted in all mealtime environment scales by 6 months, including the physical environment (z = -3.06, p = 0.013), social environment (z = -3.69, p = 0.001), relationship and person-centred scale (z = -3.51, p = 0.003), and overall environment scale (z = -3.60, p = 0.002). This practice change initiative, which focused on enhancing stakeholder engagement, provided a feasible method for increasing the practice of person-centred care during mealtimes in an RCH through the application of supportive leadership, collaborative decision making, and staff engagement.
Jamie Gundry’s dramatic image of a white-tailed eagle (Haliaeetus albicilla) on the cover of this book reflects the twisting changes in fortune experienced by this species, with a revival that can be attributed to a successful interplay of science, policy and practice. White-tailed eagles were historically much more widely distributed than they are today (Yalden, 2007), once breeding across much of Europe, but by the early twentieth century the species was extinct across much of western and southern Europe. The main cause of its decline was persecution by farmers and shepherds, who considered the eagles a threat to their livestock, but, along with other raptors, white-tailed eagles were also seriously affected by DDT in the 1960s and 1970s, which had disastrous effects on the breeding success of remaining populations.
In the Anthropocene, when our environment is changing rapidly and the windows of opportunity for action to prevent further biodiversity loss are narrow, conservation researchers are increasingly encouraged to think and operate beyond the traditional approaches of producing peer-reviewed papers and presenting results to other members of the research community. Indeed, the perception that researchers belong in their ivory tower, from which they deliver evidence for others to interpret, disseminate and use in decision-making, is thankfully now widely recognised as outdated. The rise of fake news, a deliberate lack of consideration for scientific evidence, and changes to the ways of assessing the value of researchers’ work probably all play a role in supporting this shift in perception. Moreover, for many researchers, the prospect of their work ‘making a difference’ and having an impact on wider society is at least as great a motivation for doing research as generating new knowledge, however interesting that may be.
Conservation research is essential for advancing knowledge but to make an impact scientific evidence must influence conservation policies, decision making and practice. This raises a multitude of challenges. How should evidence be collated and presented to policymakers to maximise its impact? How can effective collaboration between conservation scientists and decision-makers be established? How can the resulting messages be communicated to bring about change? Emerging from a successful international symposium organised by the British Ecological Society and the Cambridge Conservation Initiative, this is the first book to practically address these questions across a wide range of conservation topics. Well-renowned experts guide readers through global case studies and their own experiences. A must-read for practitioners, researchers, graduate students and policymakers wishing to enhance the prospect of their work 'making a difference'. This title is also available as Open Access on Cambridge Core.
A sphere sinking through a chemical gradient drags fluid with it, deforming the gradient. The sphere leaves a trail of gradient enhancement that persists longer than the velocity disturbance in the Reynolds
$10^{-2}\leqslant Re\leqslant 10^{2}$
, Froude
$10^{-1}\leqslant Fr\leqslant 10^{3}$
and Péclet
$10^{2}<Pe\leqslant 10^{6}$
regime considered here. We quantify the enhancement of the gradient and the diffusive flux in the trail of disturbed chemical left by the passing sphere using a combination of numerical simulations and scaling analyses. When
$Fr$
is large and buoyancy forces are negligible, dragged isosurfaces of chemical form a boundary layer of thickness
$\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}$
around the sphere with diameter
$l$
. We derive the scaling
$\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}/l\sim \mathit{Pe}^{-1/3}$
from the balance of advection and diffusion in the chemical boundary layer. The sphere displaces a single isosurface of chemical a maximum distance
$\mathit{L}_{Def}$
that increases as
$\mathit{L}_{Def}/l\sim l/\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}\sim \mathit{Pe}^{1/3}$
. Increased flux through the chemical boundary layer moving with the sphere is described by a Sherwood number,
$Sh\sim l/\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}\sim \mathit{Pe}^{1/3}$
. The gradient enhancement trail extends much farther than
$\mathit{L}_{Def}$
as displaced isosurfaces slowly return to their original positions through diffusion. In the reference frame of a chemical isosurface moving past the sphere, a new quantity describing the Lagrangian flux is found to scale as
$\mathit{M}\sim (\mathit{L}_{Def}/l)^{2}\sim \mathit{Pe}^{2/3}$
. The greater
$\mathit{Pe}$
dependence of
$\mathit{M}$
versus
$Sh$
demonstrates the importance of the deformation trail for determining the total flux of chemical in the system. For
$\mathit{Fr}\geqslant 10$
, buoyancy forces are weak compared to the motion of the sphere and the preceding results are retained. Below
$\mathit{Fr}=10$
, an additional Froude dependence is found and
$l/\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}\sim Sh\sim Re^{1/6}Fr^{-1/6}Pe^{1/3}$
. Buoyancy forces suppress gradient deformation downstream, resulting in
$\mathit{L}_{Def}/l\sim Re^{-1/3}Fr^{1/3}Pe^{1/3}$
and
$\mathit{M}\sim Re^{-1/3}Fr^{1/3}Pe^{2/3}$
. The productivity of marine plankton – and therefore global carbon and oxygen cycles – depends on the availability of microscale gradients of chemicals. Because most plankton exist in the fluids regime under consideration, this work describes a new mechanism by which sinking particles and plankton can stir weak ambient chemical gradients a distance
$\mathit{L}_{Def}$
and increase chemical flux in the trail by a factor of
$\mathit{M}$
.
This study investigated metabolic, endocrine, appetite and mood responses to a maximal eating occasion in fourteen men (mean: age 28 (sd 5) years, body mass 77·2 (sd 6·6) kg and BMI 24·2 (sd 2·2) kg/m2) who completed two trials in a randomised crossover design. On each occasion, participants ate a homogenous mixed-macronutrient meal (pizza). On one occasion, they ate until ‘comfortably full’ (ad libitum) and on the other, until they ‘could not eat another bite’ (maximal). Mean energy intake was double in the maximal (13 024 (95 % CI 10 964, 15 084) kJ; 3113 (95 % CI 2620, 3605) kcal) compared with the ad libitum trial (6627 (95 % CI 5708, 7547) kJ; 1584 (95 % CI 1364, 1804) kcal). Serum insulin incremental AUC (iAUC) increased approximately 1·5-fold in the maximal compared with ad libitum trial (mean: ad libitum 43·8 (95 % CI 28·3, 59·3) nmol/l × 240 min and maximal 67·7 (95 % CI 47·0, 88·5) nmol/l × 240 min, P < 0·01), but glucose iAUC did not differ between trials (ad libitum 94·3 (95 % CI 30·3, 158·2) mmol/l × 240 min and maximal 126·5 (95 % CI 76·9, 176·0) mmol/l × 240 min, P = 0·19). TAG iAUC was approximately 1·5-fold greater in the maximal v. ad libitum trial (ad libitum 98·6 (95 % CI 69·9, 127·2) mmol/l × 240 min and maximal 146·4 (95 % CI 88·6, 204·1) mmol/l × 240 min, P < 0·01). Total glucagon-like peptide-1, glucose-dependent insulinotropic peptide and peptide tyrosine–tyrosine iAUC were greater in the maximal compared with ad libitum trial (P < 0·05). Total ghrelin concentrations decreased to a similar extent, but AUC was slightly lower in the maximal v. ad libitum trial (P = 0·02). There were marked differences on appetite and mood between trials, most notably maximal eating caused a prolonged increase in lethargy. Healthy men have the capacity to eat twice the energy content required to achieve comfortable fullness at a single meal. Postprandial glycaemia is well regulated following initial overeating, with elevated postprandial insulinaemia probably contributing.
In 2018, the Alliance for Open Media (AOMedia) finalized its first video compression format AV1, which is jointly developed by the industry consortium of leading video technology companies. The main goal of AV1 is to provide an open source and royalty-free video coding format that substantially outperforms state-of-the-art codecs available on the market in compression efficiency while remaining practical decoding complexity as well as being optimized for hardware feasibility and scalability on modern devices. To give detailed insights into how the targeted performance and feasibility is realized, this paper provides a technical overview of key coding techniques in AV1. Besides, the coding performance gains are validated by video compression tests performed with the libaom AV1 encoder against the libvpx VP9 encoder. Preliminary comparison with two leading HEVC encoders, x265 and HM, and the reference software of VVC is also conducted on AOM's common test set and an open 4k set.