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Petrology and geochemistry of the NWA 3368 Eucrite
We report the petrology and geochemistry of NWA 3368, a new non-cumulate, monomict eucrite breccia with a variety of clast sizes and a pink-tinted matrix. Analytical techniques include electron microprobe, INAA, and ICP-MS
Ultrasonographic-based predictive factors influencing successful return to racing after superficial digital flexor tendon injuries in flat racehorses: a retrospective cohort study in 469 Thoroughbred racehorses in Hong Kong
Background: Superficial digital flexor tendon (SDFT) injury is an important health and welfare concern in racehorses. It is generally diagnosed with ultrasonography, predictive ultrasonographic features have not been reported.
Objectives: To determine ultrasonographic features of forelimb SDFT injury at initial presentation in Thoroughbred racehorses, that could predict a successful return to racing (completing > or = 5 races).
Study Design: Retrospective cohort study.
Methods: Digitised ultrasonographic images of 469 horses with forelimb SDFT injuries from the Hong Kong Jockey Club (2003-2014) were evaluated, using a previously validated ultrasonographic scoring system. Six ultrasonographic parameters were evaluated (type and extent of the injury, location, echogenicity, cross-sectional area and longitudinal fiber pattern of the maximal injury zone (MIZ)), as well as horse signalment, retirement date and number of races before and after injury. Data was analysed by generalized linear regression with significance at P<0.05.
Results: Cases were divided in two groups: 1) For cases of SDFT tendonitis with core lesions, cross-sectional area at the MIZ was the most significant factor determining a successful return to racing (p=0.03). If the lesion was or > or = 50% this decreased to 11-16%. 2) For cases of SDFT tendonitis without a core lesion, longitudinal fiber pattern at the MIZ best predicted a successful return to racing (P=0.002); if the affected longitudinal fiber pattern was or = 75% this decreased to 14%.
Main Limitations: Prognostic information may not be applicable to other breeds/disciplines.
Conclusions: This is the first study to describe ultrasonographic features of forelimb SDFT injuries at initial presentation that were predictive of successful return to racing. The outcomes will assist with early, evidence-based decisions on prognosis in Thoroughbred racehorses
Nonequilibrium dynamics of random field Ising spin chains: exact results via real space RG
Non-equilibrium dynamics of classical random Ising spin chains are studied
using asymptotically exact real space renormalization group. Specifically the
random field Ising model with and without an applied field (and the Ising spin
glass (SG) in a field), in the universal regime of a large Imry Ma length so
that coarsening of domains after a quench occurs over large scales. Two types
of domain walls diffuse in opposite Sinai random potentials and mutually
annihilate. The domain walls converge rapidly to a set of system-specific
time-dependent positions {\it independent of the initial conditions}. We obtain
the time dependent energy, magnetization and domain size distribution
(statistically independent). The equilibrium limits agree with known exact
results. We obtain exact scaling forms for two-point equal time correlation and
two-time autocorrelations. We also compute the persistence properties of a
single spin, of local magnetization, and of domains. The analogous quantities
for the spin glass are obtained. We compute the two-point two-time correlation
which can be measured by experiments on spin-glass like systems. Thermal
fluctuations are found to be dominated by rare events; all moments of truncated
correlations are computed. The response to a small field applied after waiting
time , as measured in aging experiments, and the fluctuation-dissipation
ratio are computed. For ,
, it equals its equilibrium value X=1, though time
translational invariance fails. It exhibits for aging regime
with non-trivial , different from mean field.Comment: 55 pages, 9 figures, revte
On the application of population-based structural health monitoring in aerospace engineering
One of the major obstacles to the widespread uptake of data-based Structural Health Monitoring so far, has been the lack of damage-state data for the (mostly high-value) structures of interest. To address this issue, a methodology for sharing data and models between structures has been developed–Population-Based Structural Health Monitoring (PBSHM). PBSHM works on the principle that, if populations of structures are sufficiently similar, or share sections which can be considered similar, then data and models can be shared between them for use in diagnostic inference. The PBSHM methodology therefore relies on two key components: firstly, identifying whether structures are sufficiently similar for successful transfer of diagnostics; this is achieved by the use of an abstract representation of structures. Secondly, machine learning techniques are exploited to effectively transfer information between the structures in a way that improves damage detection and classification across the whole population. Although PBSHM has been conceived to deal with large and general classes of structures, much of the detailed developments presented so far have concerned bridges; the aim of this paper is to provide similarly detailed discussions in the aerospace context. The overview here will examine data transfer between aircraft components, as well as illustrating how one might construct an abstract representation of a full aircraft
Ultrasonographic-based predictive factors influencing successful return to racing after superficial digital flexor tendon injuries in flat racehorses: a retrospective cohort study in 469 Thoroughbred racehorses in Hong Kong
Background: Superficial digital flexor tendon (SDFT) injury is an important health and welfare concern in racehorses. It is generally diagnosed with ultrasonography, predictive ultrasonographic features have not been reported.
Objectives: To determine ultrasonographic features of forelimb SDFT injury at initial presentation in Thoroughbred racehorses, that could predict a successful return to racing (completing > or = 5 races).
Study Design: Retrospective cohort study.
Methods: Digitised ultrasonographic images of 469 horses with forelimb SDFT injuries from the Hong Kong Jockey Club (2003-2014) were evaluated, using a previously validated ultrasonographic scoring system. Six ultrasonographic parameters were evaluated (type and extent of the injury, location, echogenicity, cross-sectional area and longitudinal fiber pattern of the maximal injury zone (MIZ)), as well as horse signalment, retirement date and number of races before and after injury. Data was analysed by generalized linear regression with significance at P<0.05.
Results: Cases were divided in two groups: 1) For cases of SDFT tendonitis with core lesions, cross-sectional area at the MIZ was the most significant factor determining a successful return to racing (p=0.03). If the lesion was or > or = 50% this decreased to 11-16%. 2) For cases of SDFT tendonitis without a core lesion, longitudinal fiber pattern at the MIZ best predicted a successful return to racing (P=0.002); if the affected longitudinal fiber pattern was or = 75% this decreased to 14%.
Main Limitations: Prognostic information may not be applicable to other breeds/disciplines.
Conclusions: This is the first study to describe ultrasonographic features of forelimb SDFT injuries at initial presentation that were predictive of successful return to racing. The outcomes will assist with early, evidence-based decisions on prognosis in Thoroughbred racehorses
The emergence of the cortisol circadian rhythm in monozygotic and dizygotic twin infants: the twin-pair synchrony
OBJECTIVE: Studies on the influence of genetic factors on the ontogeny of cortisol circadian rhythm in infants are lacking. This study evaluated the influence of twinning and the heritability on the age of emergence of salivary cortisol rhythm. DESIGN AND SUBJECTS: A longitudinal study was performed using salivary samples obtained during morning and night, at 2, 4, 8, 12, 16, 20 and 24 weeks of postnatal life in 34 infants, 10 monozygotic (MZ) and 7 dizygotic (DZ) twin pairs. Salivary cortisol was determined by radioimmunoassay (RIA). Zigosity was verified by DNA analysis of at least 13 short tandem repeat polymorphisms. Difference of the emergence of cortisol circadian rhythm, within each twin pair, the intraclass correlation coefficient and the heritability index (h(2)) were calculated. RESULTS: The mean (± SEM) age of emergence of salivary cortisol circadian rhythm was similar in MZ and DZ (7·8 ± 1·0 vs 7·4 ± 1·3 weeks). Seven pairs showed coincidence of the emergence of cortisol rhythm. Ten pairs were not coincident; among them the within-pair difference of emergence of salivary circadian rhythm was similar in both MZ and DZ groups. The intraclass correlation coefficients were rMZ = 0·60, P = 0·02; and rDZ = 0·65, P = 0·03, respectively. The heritability index (h(2)) was 0·21 (ns). CONCLUSIONS: Salivary circadian rhythm appeared at the same postnatal age in MZ and DZ twin infants. Although several physiological aspects might be involved, the heritability index, obtained in the present study, suggests less genetic than environmental impact on the age of the onset of the cortisol circadian rhythm. Our data also indicated that each twin-pair show synchrony because they probably shared prenatal and postnatal environmental synchronizers
Multilayered feed forward Artificial Neural Network model to predict the average summer-monsoon rainfall in India
In the present research, possibility of predicting average summer-monsoon
rainfall over India has been analyzed through Artificial Neural Network models.
In formulating the Artificial Neural Network based predictive model, three
layered networks have been constructed with sigmoid non-linearity. The models
under study are different in the number of hidden neurons. After a thorough
training and test procedure, neural net with three nodes in the hidden layer is
found to be the best predictive model.Comment: 19 pages, 1 table, 3 figure
Exact Occupation Time Distribution in a Non-Markovian Sequence and Its Relation to Spin Glass Models
We compute exactly the distribution of the occupation time in a discrete {\em
non-Markovian} toy sequence which appears in various physical contexts such as
the diffusion processes and Ising spin glass chains. The non-Markovian property
makes the results nontrivial even for this toy sequence. The distribution is
shown to have non-Gaussian tails characterized by a nontrivial large deviation
function which is computed explicitly. An exact mapping of this sequence to an
Ising spin glass chain via a gauge transformation raises an interesting new
question for a generic finite sized spin glass model: at a given temperature,
what is the distribution (over disorder) of the thermally averaged number of
spins that are aligned to their local fields? We show that this distribution
remains nontrivial even at infinite temperature and can be computed explicitly
in few cases such as in the Sherrington-Kirkpatrick model with Gaussian
disorder.Comment: 10 pages Revtex (two-column), 1 eps figure (included
Anomalous diffusion, Localization, Aging and Sub-aging effects in trap models at very low temperature
We study in details the dynamics of the one dimensional symmetric trap model,
via a real-space renormalization procedure which becomes exact in the limit of
zero temperature. In this limit, the diffusion front in each sample consists in
two delta peaks, which are completely out of equilibrium with each other. The
statistics of the positions and weights of these delta peaks over the samples
allows to obtain explicit results for all observables in the limit .
We first compute disorder averages of one-time observables, such as the
diffusion front, the thermal width, the localization parameters, the
two-particle correlation function, and the generating function of thermal
cumulants of the position. We then study aging and sub-aging effects : our
approach reproduces very simply the two different aging exponents and yields
explicit forms for scaling functions of the various two-time correlations. We
also extend the RSRG method to include systematic corrections to the previous
zero temperature procedure via a series expansion in . We then consider the
generalized trap model with parameter and obtain that the
large scale effective model at low temperature does not depend on in
any dimension, so that the only observables sensitive to are those
that measure the `local persistence', such as the probability to remain exactly
in the same trap during a time interval. Finally, we extend our approach at a
scaling level for the trap model in and obtain the two relevant time
scales for aging properties.Comment: 33 pages, 3 eps figure
Ethnicity and consumption: South Asian food shopping patterns in Britain 1947-75
Authors' draft version also available on University of Surrey e-print repository. Final version published by Sage and available at http://joc.sagepub.com/This article reviews the literature that explores the relationship between ethnic
identities and food consumption, with particular reference to business management
studies. It focuses on the food shopping practices of south Asians in Britain in the
period 1947 to 1975, to illustrate the need for more historically contextualized studies
that can provide a more nuanced exploration of any interconnections between ethnic
identity and shopping behaviour. The article draws on a reasonably long-standing
interest in ethnicity and consumption in marketing studies, and explores the
conceptual use of acculturation within this literature. The arguments put forward are
framed by recent interdisciplinary studies of the broader relationship between
consumption and identity, which stress the importance of contextualizing any
influence of ethnic identifications through a wider consideration of other factors
including societal status, gender and age, rather than giving it singular treatment. The
article uses a body of empirical research drawn from recent oral histories, to explore
how these factors informed everyday shopping practices among south Asians in Britain. It examines some of the shopping and wider food provisioning strategies
adopted by early immigrants on arrival in Britain. It considers the interaction between
the south Asian population and the changing retail structure, in the context of the
development of self-service and the supermarket. Finally, it demonstrates how age,
gender and socioeconomic status interacted with ethnic identities to produce
variations in shopping patterns
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