1,686 research outputs found

### The Costs of Biosecurity at the Farm Level: the Case of Finnish Broiler

In the European Union, the animal health and food safety strategy includes managing biosecurity along the entire production chain. Farm-level biosecurity provides the foundation for this. However, the farm-level costs of preventive biosecurity have rarely been assessed. Yet many risk management practices are in place constantly regardless of whether there is a disease outbreak or not. We contribute towards filling this information gap by studying the costs incurred in preventive biosecurity by the Finnish poultry farms. In a preliminary analysis, we find that the cost of biosecurity is some 3.55 cents per bird for broiler producers and 75.7 cents per bird for hatching egg producers. The results indicate that work-time devoted to biosecurity represents some 8% of total work time on broiler farms and about 5% on breeder farms.Biosecurity, on-farm costs, poultry, Livestock Production/Industries,

### Isotope effect on superconductivity in Josephson coupled stripes in underdoped cuprates

Inelastic neutron scattering data for YBaCuO as well as for LaSrCuO indicate
incommensurate neutron scattering peaks with incommensuration $\delta(x)$ away
from the $(\pi,\pi)$ point. $T_c(x)$ can be replotted as a linear function of
the incommensuration for these materials. This linear relation implies that the
constant that relates these two quantities, one being the incommensuration
(momentum) and another being $T_c(x)$ (energy), has the dimension of velocity
we denote $v^*$: $k_B T_c(x) = \hbar v^* \delta(x)$. We argue that this
experimentally derived relation can be obtained in a simple model of Josephson
coupled stripes. Within this framework we address the role of the $O^{16} \to
O^{18}$ isotope effect on the $T_c(x)$. We assume that the incommensuration is
set by the {\em doping} of the sample and is not sensitive to the oxygen
isotope given the fixed doping. We find therefore that the only parameter that
can change with O isotope substitution in the relation $T_c(x) \sim \delta(x)$
is the velocity $v^*$. We predict an oxygen isotope effect on $v^*$ and expect
it to be $\simeq 5%$.Comment: 4 pages latex file, 2 eps fig

### Universal Amplitude Ratios in the Ising Model in Three Dimensions

We use a high-precision Monte Carlo simulation to determine the universal
specific-heat amplitude ratio A+/A- in the three-dimensional Ising model via
the impact angle \phi of complex temperature zeros. We also measure the
correlation-length critical exponent \nu from finite-size scaling, and the
specific-heat exponent \alpha through hyperscaling. Extrapolations to the
thermodynamic limit yield \phi = 59.2(1.0) degrees, A+/A- = 0.56(3), \nu =
0.63048(32) and \alpha = 0.1086(10). These results are compatible with some
previous estimates from a variety of sources and rule out recently conjectured
exact values.Comment: 17 pages, 5 figure

### Multivariable Christoffel-Darboux kernels and characteristic polynomials of random hermitian matrices

We study multivariable Christoffel-Darboux kernels, which may be viewed as reproducing kernels for antisymmetric orthogonal polynomials, and also as correlation functions for products of characteristic polynomials of random Hermitian matrices. Using their interpretation as reproducing kernels, we obtain simple proofs of Pfaffian and determinant formulas, as well as Schur polynomial expansions, for such kernels. In subsequent work, these results are applied in combinatorics (enumeration of marked shifted tableaux) and number theory (representation of integers as sums of squares)

### Identifying leverage points for strengthening adaptive capacity to climate change

Leverage points from systems research are increasingly important to understand how to support transformations towards sustainability, but few studies have considered leverage points in strengthening adaptive capacity to climate change. The existing literature mainly considers strengthening adaptive capacity as a steady and linear process. This article explores possibilities to fast track positive adaptive capacity trajectories of small-scale farmers in the Northern Region of Ghana. Leverage points were identified by triangulating data from semi-structured interviews with farmers (n=72), key informant interviews (n=7) and focus group discussions (FG1 n=17; FG2 n=20). The results present two ways to approach adaptation planning: 1) using four generic leverage points (gender equality, social learning, information and knowledge, and access to finance) or 2) combining the adaptive capacity and leverage point frameworks, thereby creating 15 associations. The generic points provide a set of topics as a starting point for policy and intervention planning activities, while the 15 associations support the identification of place-specific leverage points. Four benefits of using leverage points for adaptive capacity in adaptation planning were identified: guidance on where to intervene in a system, ability to deal with complex systems, inclusion of both causal and teleological decision-making, and a possibility to target deep, transformative change. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Peer reviewe

### The Vertex-Face Correspondence and the Elliptic 6j-symbols

A new formula connecting the elliptic $6j$-symbols and the fusion of the
vertex-face intertwining vectors is given. This is based on the identification
of the $k$ fusion intertwining vectors with the change of base matrix elements
from Sklyanin's standard base to Rosengren's natural base in the space of even
theta functions of order $2k$. The new formula allows us to derive various
properties of the elliptic $6j$-symbols, such as the addition formula, the
biorthogonality property, the fusion formula and the Yang-Baxter relation. We
also discuss a connection with the Sklyanin algebra based on the factorised
formula for the $L$-operator.Comment: 23 page

### An (inverse) Pieri formula for Macdonald polynomials of type C

We give an explicit Pieri formula for Macdonald polynomials attached to the
root system C_n (with equal multiplicities). By inversion we obtain an explicit
expansion for two-row Macdonald polynomials of type C.Comment: 31 pages, LaTeX, to appear in Transformation Group

### Evaluation of shared genetic susceptibility loci between autoimmune diseases and schizophrenia based on genome-wide association studies.

BACKGROUND: Epidemiological studies have documented higher than expected comorbidity (or, in some cases, inverse comorbidity) between schizophrenia and several autoimmune disorders. It remains unknown whether this comorbidity reflects shared genetic susceptibility loci. AIMS: The present study aimed to investigate whether verified genome wide significant variants of autoimmune disorders confer risk of schizophrenia, which could suggest a common genetic basis. METHODS: Seven hundred and fourteen genome wide significant risk variants of 25 autoimmune disorders were extracted from the NHGRI GWAS catalogue and examined for association to schizophrenia in the Psychiatric Genomics Consortium schizophrenia GWAS samples (36,989 cases and 113,075 controls). RESULTS: Two independent loci at 4q24 and 6p21.32-33 originally identified from GWAS of autoimmune diseases were found genome wide associated with schizophrenia (1.7 × 10(-8 )≥( )p ≥ 4.0 × 10(-21)). While these observations confirm the existence of shared genetic susceptibility loci between schizophrenia and autoimmune diseases, the findings did not show a significant enrichment. CONCLUSION: The findings do not support a genetic overlap in common SNPs between autoimmune diseases and schizophrenia that in part could explain the observed comorbidity from epidemiological studies

### SOS model partition function and the elliptic weight functions

We generalize a recent observation [arXiv:math/0610433] that the partition
function of the 6-vertex model with domain-wall boundary conditions can be
obtained by computing the projections of the product of the total currents in
the quantum affine algebra $U_{q}(\hat{\mathfrak{sl}}_{2})$ in its current
realization. A generalization is proved for the the elliptic current algebra
[arXiv:q-alg/9703018,arXiv:q-alg/9601022]. The projections of the product of
total currents are calculated explicitly and are represented as integral
transforms of the product of the total currents. We prove that the kernel of
this transform is proportional to the partition function of the SOS model with
domain-wall boundary conditions.Comment: 21 pages, 5 figures, requires iopart packag

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