13,749 research outputs found
Randomised positive control trial of NSAID and antimicrobial treatment for calf fever caused by pneumonia
One hundred and fifty-four preweaning calves were followed between May and October 2015. Calves were fitted with continuous monitoring temperature probes (TempVerified FeverTag), programmed so a flashing light emitting diode (LED) light was triggered following six hours of a sustained ear canal temperature of ≥39.7°C. A total of 83 calves (61.9 per cent) developed undifferentiated fever, with a presumptive diagnosis of pneumonia through exclusion of other calf diseases. Once fever was detected, calves were randomly allocated to treatment groups. Calves in group 1 (NSAID) received 2 mg/kg flunixin meglumine (Allevinix, Merial) for three consecutive days and group 2 (antimicrobial) received 6 mg/kg gamithromycin (Zactran, Merial). If fever persisted for 72 hours after the initial treatment, calves were given further treatment (group 1 received antimicrobial and group 2 received NSAID). Calves in group 1 (NSAID) were five times more likely (P=0.002) to require a second treatment (the antimicrobial) after 72 hours to resolve the fever compared with the need to give group 2 (antimicrobial) calves a second treatment (NSAID). This demonstrates the importance of ongoing monitoring and follow-up of calves with respiratory disease. However, of calves with fever in group 1 (NSAID), 25.7 per cent showed resolution following NSAID-only treatment with no detrimental effect on the development of repeated fever or daily live weight gain. This suggests that NSAID alone may be a useful first-line treatment, provided adequate attention is given to ongoing monitoring to identify those cases that require additional antimicrobial treatment
Self-contained Kondo effect in single molecules
Kondo coupling of f and conduction electrons is a common feature of
f-electron intermetallics. Similar effects should occur in carbon ring
systems(metallocenes). Evidence for Kondo coupling in Ce(C8H8)2 (cerocene) and
the ytterbocene Cp*2Yb(bipy) is reported from magnetic susceptibility and
L_III-edge x-ray absorption spectroscopy. These well-defined systems provide a
new way to study the Kondo effect on the nanoscale, should generate insight
into the Anderson Lattice problem, and indicate the importance of this
often-ignored contribution to bonding in organometallics.Comment: 4 pages, 5 figures (eps
Future of Public Parks: Policy, Practice and Research
On Thursday 13th July 2017, the University of Leeds hosted a major one-day national conference entitled ‘The Future of Public Parks’ at The British Academy in London. The conference was generously sponsored by the Leeds Social Sciences Institute and idverde, with support from The Parks Alliance, Historic England and Groundwork. Some 79 delegates participated in a lively and engaging event which drew together innovative thinking and learning from policy, practice and research on ways to maximise the value of parks as public assets in the twenty-first century, and to consider challenges that threaten the sustainability of public parks in the future.
The event brought together academics from diverse disciplines, funding bodies, policy-makers and practitioners from the across the public, voluntary and private sectors. At a time when the future of public parks is both in the balance and in the national spotlight, the presenters and delegates explored important issues and challenges that inform diverse models of park management whether local authorities, trusts, charities or private sector. These included questions about health and well-being, social and educational use, community involvement and strategies for generating income. The conference provided a timely opportunity to foster a research-informed, policy and practice-orientated dialogue about park futures and offered a platform for advancing public debate in light of the findings and recommendations of the Communities and Local Government Select Committee Inquiry. Importantly, it provided a unique opportunity for multi-disciplinary, inter-professional and cross-sectoral debate that enabled delegates to explore common questions, mutual strategies and shared interest in promoting the social role and value of public parks
Universal Dynamic Conductivity and Quantized Visible Opacity of Suspended Graphene
We show that the optical transparency of suspended graphene is defined by the
fine structure constant, alpha, the parameter that describes coupling between
light and relativistic electrons and is traditionally associated with quantum
electrodynamics rather than condensed matter physics. Despite being only one
atom thick, graphene is found to absorb a significant (pi times alpha=2.3%)
fraction of incident white light, which is a consequence of graphene's unique
electronic structure. This value translates into universal dynamic conductivity
G =e^2/4h_bar within a few percent accuracy
Quantifying structural damage from self-irradiation in a plutonium superconductor
The 18.5 K superconductor PuCoGa5 has many unusual properties, including
those due to damage induced by self-irradiation. The superconducting transition
temperature decreases sharply with time, suggesting a radiation-induced Frenkel
defect concentration much larger than predicted by current radiation damage
theories. Extended x-ray absorption fine-structure measurements demonstrate
that while the local crystal structure in fresh material is well ordered, aged
material is disordered much more strongly than expected from simple defects,
consistent with strong disorder throughout the damage cascade region. These
data highlight the potential impact of local lattice distortions relative to
defects on the properties of irradiated materials and underscore the need for
more atomic-resolution structural comparisons between radiation damage
experiments and theory.Comment: 7 pages, 5 figures, to be published in PR
Spaces Apart: Public Parks and the Differentiation of Space in Leeds, 1850-1914
While the Victorian ideal of the public park is well understood, we know less of how local governors sought to realize this ideal in practice. This article is concerned with park-making as a process – contingent, unstable, open – rather than with parks as outcomes – determined, settled, closed. It details how local governors bounded, designed and regulated park spaces to differentiate them as ‘spaces apart’ within the city, and how this programme of spatial governance was obstructed, frustrated and diverted by political, environmental and social forces. The article also uses this historical analysis to provide a new perspective on the future prospects of urban parks today
P and T Violation From Certain Dimension Eight Weinberg Operators
Dimension eight operators of the Weinberg type have been shown to give
important contributions to CP violating phenomena, such as the electric dipole
moment of the neutron. In this note we show how operators related to these (and
expected to occur on equal footing) can give rise to time-reversal violating
phenomena such as atomic electric dipole moments. We also estimate the induced
parity violating phenomena such as small ``wrong'' parity admixtures in atomic
states and find that they are negligible. Uses harvmac.tex and epsf.tex; one
figure submitted as a uuencoded, compressed EPS file.Comment: 6 pages, EFI-92-5
Quenched Chiral Perturbation Theory for Vector Mesons
We develop quenched chiral perturbation theory for vector mesons made of
light quarks, in the limit where the vector meson masses are much larger than
the pion mass. We use this theory to extract the leading nonanalytic dependence
of the vector meson masses on the masses of the light quarks. By comparing with
analogous quantities computed in ordinary chiral perturbation theory, we
estimate the size of quenching effects, observing that in general they can be
quite large. This estimate is relevant to lattice simulations, where the
mass is often used to set the lattice spacing.Comment: 18 pages, 8 figures, uses REVTeX and epsf.st
Application of Waste Glass Powder as a Partial Cement Substitute towards more Sustainable Concrete Production
Use of waste materials in concrete is now a global trend for efficient waste management so as to achieve a sustainable green environment and with the added advantages of preserving the natural resources as well as producing a better performing concrete. This study examined the properties of concrete containing ground waste glass powder (GP) as partial replacement for cement. The waste glass was finely grounded into powder and the morphology imagery of the powder materials was carried out using scanning electron microscopy (SEM). Moreover, the chemical composition of the glass powdered material was determined using X-ray fluorescence (XRF). Laboratory tests were carried out to determine the strength activity index, workability, split tensile and compressive strength properties of the concrete with 0%, 15%, 18%, 21%, 24%, 27% and 30% partial replacement of cement with the ground waste glass powder. The results showed that the oxides composition of the glass powder meets the requirements for pozzolanic material, while the SEM morphology shows materials of amorphous flaky solid masses, and based on the 28-day strength activity index, concrete containing 21% cement replacement shows a higher strength index above the recommended 75%. It was also observed that workability of the concrete reduced with increase in percentage glass content while significant improvement of the compressive strength of the concrete was achieved at 21% cement replacement, after which a decrease in strength with increasing percentage glass content was observed. The revealed results were confirmed by the microstructural examination using SEM showing a denser concrete at 21% cement replacement but increase porosity as the glass content increases. However, a decrease in split tensile strength was observed with increasing glass content. The results clearly showed that it is possible to produce moderate strength sustainable concrete for structural application using 20% glass powder as cement replacement
Direct Observation of High-Temperature Polaronic Behavior In Colossal Magnetoresistive Manganites
The temperature dependence of the electronic and atomic structure of the
colossal magnetoresistive oxides (x = 0.3, 0.4) has
been studied using core and valence level photoemission, x-ray absorption and
emission, and extended x-ray absorption fine structure spectroscopy. A dramatic
and reversible change of the electronic structure is observed on crossing the
Curie temperature, including charge localization and spin moment increase of
Mn, together with Jahn-Teller distortions, both signatures of polaron
formation. Our data are also consistent with a phase-separation scenario.Comment: 5 pages, 4 figures, revte
- …