13,283 research outputs found
Detection of abnormal recordings in Irish milk recorded data
peer-reviewedThe objective of this study was to detect abnormal recordings of milk yield, fat concentration and protein concentration in Irish milk-recorded data. The data consisted of 14,956 records from both commercial and experimental herds with 92% of the recordings recorded manually and the remainder recorded electronically. The method used in this paper was a modified version of the method employed by the Animal Improvement Programs Laboratory in Maryland, USA and conformed with the guidelines outlined by the International Committee of Animal Recording. The results illustrate the effectiveness of detecting abnormal recordings in Irish milk records. The method described in this paper, defines the upper and lower limits for each production trait and these limits along with the slope parameters were used to determine if a recording was abnormal or not. Three percent of milk yield recordings, 5% of fat concentration recordings and less than 1% of protein concentration recordings were found to be abnormal. The proportion of values declared abnormal in manually recorded and electronically recorded data were examined and found to be significantly different for fat concentration
Neutron Stars as Type-I Superconductors
In a recent paper by Link, it was pointed out that the standard picture of
the neutron star core composed of a mixture of a neutron superfluid and a
proton type-II superconductor is inconsistent with observations of a long
period precession in isolated pulsars. In the following we will show that an
appropriate treatment of the interacting two-component superfluid (made of
neutron and proton Cooper pairs), when the structure of proton vortices is
strongly modified, may dramatically change the standard picture, resulting in a
type-I superconductor. In this case the magnetic field is expelled from the
superconducting regions of the neutron star leading to the formation of the
intermediate state when alternating domains of superconducting matter and
normal matter coexist.Comment: 4 page
If you can't be with the one you love, love the one you're with: How individual habituation of agent interactions improves global utility
Simple distributed strategies that modify the behaviour of selfish individuals in a manner that enhances cooperation or global efficiency have proved difficult to identify. We consider a network of selfish agents who each optimise their individual utilities by coordinating (or anti-coordinating) with their neighbours, to maximise the pay-offs from randomly weighted pair-wise games. In general, agents will opt for the behaviour that is the best compromise (for them) of the many conflicting constraints created by their neighbours, but the attractors of the system as a whole will not maximise total utility. We then consider agents that act as 'creatures of habit' by increasing their preference to coordinate (anti-coordinate) with whichever neighbours they are coordinated (anti-coordinated) with at the present moment. These preferences change slowly while the system is repeatedly perturbed such that it settles to many different local attractors. We find that under these conditions, with each perturbation there is a progressively higher chance of the system settling to a configuration with high total utility. Eventually, only one attractor remains, and that attractor is very likely to maximise (or almost maximise) global utility. This counterintutitve result can be understood using theory from computational neuroscience; we show that this simple form of habituation is equivalent to Hebbian learning, and the improved optimisation of global utility that is observed results from wellknown generalisation capabilities of associative memory acting at the network scale. This causes the system of selfish agents, each acting individually but habitually, to collectively identify configurations that maximise total utility
Dark Matter and Dark Radiation
We explore the feasibility and astrophysical consequences of a new long-range
U(1) gauge field ("dark electromagnetism") that couples only to dark matter,
not to the Standard Model. The dark matter consists of an equal number of
positive and negative charges under the new force, but annihilations are
suppressed if the dark matter mass is sufficiently high and the dark
fine-structure constant is sufficiently small. The correct relic
abundance can be obtained if the dark matter also couples to the conventional
weak interactions, and we verify that this is consistent with particle-physics
constraints. The primary limit on comes from the demand that the
dark matter be effectively collisionless in galactic dynamics, which implies
for TeV-scale dark matter. These values are
easily compatible with constraints from structure formation and primordial
nucleosynthesis. We raise the prospect of interesting new plasma effects in
dark matter dynamics, which remain to be explored.Comment: 14 pages, 6 figures Updated equations and figure
Clinical audit of rectal cancer patient referrals for Papillon contact brachytherapy
AbstractBackground and purpose:Papillon treatment is a form of contact X-ray brachytherapy (CXB) which is used as an alternative to surgery for rectal cancer. This study aimed to audit patients who were referred for and treated with CXB over a 6-year period against guidelines derived from a critical review of the evidence base.Materials and methods:Patient demographics, tumour characteristics and outcome data were gathered for 31 patients referred for CXB. A critical review of the evidence identified consensus referral criteria and outcome data against which to audit patients.Results:Referral criteria were derived from six published studies. These applied to patients unfit for surgery or stoma-averse. All referred patients had a visible tumour or scar with a tumour size under 3 cm and sited less than 12 cm from the anal verge. Nodal status varied from N0 to N2, but there was no metastatic disease present. The audited cohort demonstrated demographic equivalence, while the initial clinical complete response and recurrence rates were also comparable.Conclusion:This audit confirmed the validity of referral and treatment protocols and should guide future referrals until evidence from ongoing studies becomes available. These findings should contribute to the development of robust national guidelines.</jats:sec
Minute-of-Arc Resolution Gamma ray Imaging Experiment—MARGIE
MARGIE (Minute-of-Arc Resolution Gamma-ray Imaging Experiment) is a large area(∼104 cm2), wide field-of-view (∼1 sr), hard X-ray/gamma-ray (∼20–600 keV) coded-mask imaging telescope capable of performing a sensitive survey of both steady and transient cosmic sources. MARGIE has been selected for a NASA mission-concept study for an Ultra Long Duration (100 day) Balloon flight. We describe our program to develop the instrument based on new detector technology of either cadmium zinc telluride (CZT) semiconductors or pixellated cesium iodide (CsI) scintillators viewed by fast-timing bi-directional charge-coupled devices (CCDs). The primary scientific objectives are to image faint Gamma-Ray Bursts (GRBs) in near-real-time at the low intensity (high-redshift) end of the logN-logS distribution, thereby extending the sensitivity of present observations, and to perform a wide field survey of the Galactic plane
MARGIE: A gamma-ray burst ultra-long duration balloon mission
We are designing MARGIE as a 100 day ULDB mission to: a) detect and localize gamma-ray bursts; and b) survey the hard X-ray sky. MARGIE will consist of one small field-of-view (FOV) and four large FOV coded mask modules mounted on a balloon gondola. The burst position will be calculated onboard and disseminated in near-real time, while information about every count will be telemetered to the ground for further analysis. In a 100-day mission we will localize ∼40 bursts with peak photon fluxes from 0.14 to ∼5 ph cm−2 s−1 using 1 s integrations; the typical localization resolution will be better than ∼2 arcminutes
Strain gradient induced polarization in SrTiO3 single crystals
Piezoelectricity is inherent only in noncentrosymmetric materials, but a
piezoelectric response can also be obtained in centrosymmetric crystals if
subjected to inhomogeneous deformation. This phenomenon, known as
flexoelectricity, affects the functional properties of insulators, particularly
thin films of high permittivity materials. We have measured
strain-gradient-induced polarization in single crystals of paraelectric
SrTiO as a function of temperature and orientation down to and below the
105 K phase transition. Estimates were obtained for all the components of the
flexoelectric tensor, and calculations based on these indicate that local
polarization around defects in SrTiO may exceed the largest ferroelectric
polarizations. A sign reversal of the flexoelectric response detected below the
phase transition suggests that the ferroelastic domain walls of SrTiO may
be polar.Comment: 4 pages, 3 figures, 1 tabl
Effect of Feeding L-Carnitine and Sunflower Seeds on CLA Content of Pasture-Fed Beef
Pasture finishing enhances levels of conjugated linoleic acids (CLA) in beef lipids (Shanta et al. 1997). CLA (e.g., C18:2 c9, t11), formed during biohydrogenation of polyunsaturated fatty acids (PUFA) in the rumen, can reduce the incidence of heart disease, cancer and obesity in humans. However, pasture finishing cattle can reduce carcass grade. Feeding pasture-fed cattle a high-grain diet for a short finishing period (~60 d) improves grades but may reduce lipid CLA levels. A feeding regime is required that maintains the positive nutritional attributes of pasture-fed beef and improves the meat grade. The objective of this study was to investigate the effects of adding sunflower seeds (SFS), a good source of PUFA (Mir et al. 2000), or carnitine, a vitamin-like compound shown to increase fat deposition and marbling in cattle, to finishing diets of pasture-fed cattle on lipid fatty acid profiles (FAP)
Spin Discrimination in Three-Body Decays
The identification of the correct model for physics beyond the Standard Model
requires the determination of the spin of new particles. We investigate to
which extent the spin of a new particle can be identified in scenarios
where it decays dominantly in three-body decays . Here we
assume that is a candidate for dark matter and escapes direct detection at
a high energy collider such as the LHC. We show that in the case that all
intermediate particles are heavy, one can get information on the spins of
and at the LHC by exploiting the invariant mass distribution of the two
standard model fermions. We develop a model-independent strategy to determine
the spins without prior knowledge of the unknown couplings and test it in a
series of Monte Carlo studies.Comment: 31+1 pages, 4 figures, 8 tables, JHEP.cls include
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