1,539 research outputs found
Respiratory admissions linked to air pollution in a medium sized city of the UK:A case-crossover study
This study, from the Tayside Pollution Research Programme (TPRP), aims to investigate the effects of air pollution on respiratory hospital admissions in adults and children < 16 y of age, over a 14-year period, in Dundee, Scotland (population circa 148,270). We conducted a case-crossover study using routinely collected healthcare records from Ninewells Hospital, Dundee, Scotland from 2004 to 2017. Respiratory hospitalisation events were linked to daily nitric oxide gases (NOx, NO2, NO) extracted from publicly available data over this period. We used distributed lag models to allow for delayed effects of air pollutants up to 14 days. A total of 34,192 hospital admissions for a respiratory condition were included in this study (children = 9,501; adults = 24,691). Respiratory admissions in children were significantly associated with cumulative 14-day exposure to NOx (RR for a 10 µg m–3 increase in concentration 1.020; 95% confidence interval 1.010–1.031), NO2 (RR 1.086; 95% CI 1.036–1.139) and NO (RR 1.033; 95% CI 1.016–1.052). Similar estimates were observed for acute respiratory infection categories in children. Effects appeared to be somewhat delayed, with the largest estimates mostly observed around lag 6. No significant association was seen for respiratory admissions in adults. This study shows that both NO and NO2 are associated with increased respiratory hospital admissions in children < 16 y of age, and that much more should be done to improve and enforce the established legal NOx pollution limits in cities for the sake of our children’s health.</p
Genetic testing reveals some mislabeling but general compliance with a ban on herbivorous fish harvesting in Belize
Overfishing of herbivorous fishes is one of the primary causes of Caribbean coral reef decline. In Belize, herbivorous fishes comprised 28% of the catch from 2005 to 2008. In 2009, the Belize Fisheries Department implemented a national ban on herbivorous fish harvesting to mitigate high-macroalgal cover on much of the Belize Barrier Reef. However, compliance with this approach has not been evaluated. We assessed the proportion of herbivorous fish in local markets by genetically identifying fish fillets sold in five major towns in Belize from 2009 to 2011. We found that 5-7% of 111 fillets were identified as herbivorous fish and 32-51% were mislabeled. A 5-7% proportion of parrotfish in local markets suggests some ongoing parrotfish harvesting. However, our results suggest that the ban has reduced herbivorous fish harvesting and has the potential to help facilitate the restoration of coral reef ecosystems
Scaling analysis of a model Hamiltonian for Ce impurity in a cubic metal
We introduce various exchange interactions in a model Hamiltonian for
Ce ions in cubic symmetry with three configurations (,,).
With the impurity pseudo spin , our Hamiltonian includes: (i)
One-channel Anderson model; (ii) Two-channel Anderson
model; (iii) An unforseen one-channel Anderson model with a
non-trivial fixed point; (iv) Mixing exchange interaction between the
and the conduction electron partial wave states; (v)
Multiple conduction electron partial wave states. Using the third-order scaling
(perturbative renormalization group) analysis, we study stability of various
fixed points relevant to various exchange interactions for Ce ions in
cubic symmetry.Comment: 68 pages. 4 figures are available upon request from
[email protected] (revised
Dissipation in Dynamics of a Moving Contact Line
The dynamics of the deformations of a moving contact line is studied assuming
two different dissipation mechanisms. It is shown that the characteristic
relaxation time for a deformation of wavelength of a contact line
moving with velocity is given as . The velocity
dependence of is shown to drastically depend on the dissipation
mechanism: we find for the case when the dynamics is governed
by microscopic jumps of single molecules at the tip (Blake mechanism), and
when viscous hydrodynamic losses inside the moving
liquid wedge dominate (de Gennes mechanism). We thus suggest that the debated
dominant dissipation mechanism can be experimentally determined using
relaxation measurements similar to the Ondarcuhu-Veyssie experiment [T.
Ondarcuhu and M. Veyssie, Nature {\bf 352}, 418 (1991)].Comment: REVTEX 8 pages, 9 PS figure
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The small-scale manufacture of compound animal feed (ODNRI Bulletin No. 9)
This bulletin supersedes TDRI report G67 The small-scale manufacture of compound animal feed, which was first published in 1971. lt retains a similar format to G67, but the text has been extensively revised and expanded in the light of numerous enquiries dealt with by ODNRI on all aspects of feed production in the intervening years. lt is hoped that it will act as a technical and investment guide for those interested in initiating the production of compound animal feeds, as well as acting as a useful reference report for those already actively operating in this field. Chapter 1 describes the economic background to the industry; theoretical aspects of animal nutrition are dealt with in Chapter 2; these are related to the properties of the various raw materials used in feed production in Chapter 3. Chapter 4 describes the manufacturing process and examines the physical requirements for setting up plants at various scales of output, and Chapter 5 develops cost and return models for the plants described
The DIP-approach:Student-staff partnerships as a vital tool for learning developers and educators to develop academic [and digital] literacies
Student-staff partnerships can be used to support the development of contextualised digital learning and teaching practices. This can be done by shifting the focus from IT skills to addressing a priority in learning and teaching using a digital approach that is appropriate for that discipline. The development of a formal ‘Digital Innovation Partnership’ (DIP) scheme at the University of Leicester brings students’ digital confidence, perspectives and motivation to enhance learning and teaching. It also recognises the valuable contribution and expertise of student and staff participants. This draws on the academic literacies work of Lea and Street (1998; 2006) and digital literacies work of Sharpe and Beetham (2010) to appreciate that staff and students are developing social practices that are situated within a discipline and intertwined with social, cultural and political factors, power and identity.
The reasons for the success of the scheme are explored here, with recommendations for how the model can be applied more generally to educational design to support students’ academic literacies development
Establishment of marine protected areas alone does not restore coral reef communities in Belize
A variety of factors have caused the loss of corals and fishes on coral reefs, resulting in ecological, social, and economic consequences for reef ecosystems and the people who depend on them. A widely employed management action to restore reef communities is the implementation of marine protected areas (MPAs). We measured the effectiveness of the MPA network in Belize in promoting increases in fish and coral populations and identified key ecological and environmental factors that influence reef community structure and potentially protection success. From 2009 to 2013, we annually surveyed 16 reefs in Belize, including 8 MPA sites (where ex - tractive fishing is limited or prohibited) and 8 unprotected sites. At each site, we quantified the biomass of reef fishes, coral and macroalgal cover, and several biotic and abiotic variables that are known to affect reef inhabitants. High predatory reef fish and parrotfish biomass values were associated with high reef structural complexity and low wave exposure. Mean macroalgal cover was negatively associated with parrotfish biomass in 1 protected zone. However, mean macroalgal cover remained above 40% across all sites, and no change in coral cover was observed during the study. Our results indicate that fisheries restrictions alone do not lead to increases in coral cover even when successful for fishes. We speculate that both illegal and legal fishing may be compromising Belize's MPA network goals. Furthermore, we suggest that species composition as well as local environmental conditions play key roles in coral reef recovery and should be considered when evaluating management strategies
Automatic Structure Detection in Constraints of Tabular Data
Abstract. Methods for the protection of statistical tabular data—as controlled tabular adjustment, cell suppression, or controlled rounding— need to solve several linear programming subproblems. For large multi-dimensional linked and hierarchical tables, such subproblems turn out to be computationally challenging. One of the techniques used to reduce the solution time of mathematical programming problems is to exploit the constraints structure using some specialized algorithm. Two of the most usual structures are block-angular matrices with either linking rows (primal block-angular structure) or linking columns (dual block-angular structure). Although constraints associated to tabular data have intrin-sically a lot of structure, current software for tabular data protection neither detail nor exploit it, and simply provide a single matrix, or at most a set of smallest submatrices. We provide in this work an efficient tool for the automatic detection of primal or dual block-angular struc-ture in constraints matrices. We test it on some of the complex CSPLIB instances, showing that when the number of linking rows or columns is small, the computational savings are significant
Roughening Transition in a Moving Contact Line
The dynamics of the deformations of a moving contact line on a disordered
substrate is formulated, taking into account both local and hydrodynamic
dissipation mechanisms. It is shown that both the coating transition in contact
lines receding at relatively high velocities, and the pinning transition for
slowly moving contact lines, can be understood in a unified framework as
roughening transitions in the contact line. We propose a phase diagram for the
system in which the phase boundaries corresponding to the coating transition
and the pinning transition meet at a junction point, and suggest that for
sufficiently strong disorder a receding contact line will leave a
Landau--Levich film immediately after depinning. This effect may be relevant to
a recent experimental observation in a liquid Helium contact line on a Cesium
substrate [C. Guthmann, R. Gombrowicz, V. Repain, and E. Rolley, Phys. Rev.
Lett. {\bf 80}, 2865 (1998)].Comment: 16 pages, 6 encapsulated figure
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