115 research outputs found

    Integration of production and financial models to analyse the financial impact of livestock diseases: a case study of Schmallenberg virus disease on British and French dairy farms

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    AIMS AND OBJECTIVES: The aim of the study was to investigate and compare the financial impact of Schmallenberg disease for different dairy production types in the United Kingdom and France. MATERIALS AND METHODS: Integrated production and financial models for dairy cattle were developed and applied to Schmallenberg virus (SBV) disease in a British and French context. The five main production systems that prevail in these two countries were considered. Their respective gross margins measuring the holding's profitability were calculated based on public benchmarking, literature and expert opinion data. A partial budget analysis was performed within each production model to estimate the impact of SBV in the systems modelled. Two disease scenarios were simulated: low impact and high impact. RESULTS: The model gross margin obtained per cow space and year ranged from £1014 to £1484 for the UK and from £1037 to £1890 for France depending on the production system considered. In the UK, the net SBV disease costs in £/cow space/year for an average dairy farm with 100 milking spaces were estimated between £16.3 and £51.4 in the high-impact scenario and between £8.2 and £25.9 in the low-impact scenario. For France, the net SBV disease costs in £/cow space/year ranged from £19.6 to £48.6 in the high-impact scenario and £9.7 to £22.8 in the low-impact scenario, respectively. CONCLUSION: The study illustrates how the combination of production and financial models allows assessing disease impact taking into account differing management and husbandry practices and associated price structures in the dairy sector. It supports decision-making of farmers and veterinarians who are considering disease control measures as it provides an approach to estimate baseline disease impact in common dairy production systems in the UK and France

    Formalin-induced behavioural hypersensitivity and neuronal hyperexcitability are mediated by rapid protein synthesis at the spinal level

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    Background: The mammalian target of rapamycin ( mTOR) is a key regulator of mRNA translation whose action can be inhibited by the drug rapamycin. Forms of long-term plasticity require protein synthesis and evidence indicates that mRNA in dendrites, axon terminals and cell bodies is essential for long-term synaptic plasticity. Specific to pain, shifts in pain thresholds and responsiveness are an expression of neuronal plasticity and this likely contributes to persistent pain. We investigated this by inhibiting the activity of mTOR with rapamycin at the spinal level, of rats that were subjected to the formalin test, using both behavioural and electrophysiological techniques.Results: For in vivo electrophysiology, Sprague Dawley rats were fully anaesthetised and single-unit extracellular recordings were obtained from lamina V wide dynamic range (WDR) dorsal horn spinal neurones at the region where input is received from the hind paw. Neuronal responses from naive rats showed that rapamycin-sensitive pathways were important in nociceptive-specific C-fibre mediated transmission onto WDR neurones as well mechanically-evoked responses since rapamycin was effective in attenuating these measures. Formalin solution was injected into the hind paw prior to which, rapamycin or vehicle was applied directly onto the exposed spinal cord. When rapamycin was applied to the spinal cord prior to hind paw formalin injection, there was a significant attenuation of the prolonged second phase of the formalin test, which comprises continuing afferent input to the spinal cord, neuronal hyperexcitability and an activated descending facilitatory drive from the brainstem acting on spinal neurones. In accordance with electrophysiological data, behavioural studies showed that rapamycin attenuated behavioural hypersensitivity elicited by formalin injection into the hind paw.Conclusion: We conclude that mTOR has a role in maintaining persistent pain states via mRNA translation and thus protein synthesis. We hypothesise that mTOR may be activated by excitatory neurotransmitter release acting on sensory afferent terminals as well as dorsal horn spinal neurones, which may be further amplified by descending facilitatory systems originating from higher centres in the brain

    2,6-Diamino­pyridinium tetra­phenyl­borate–1,2-bis­(5,7-dimethyl-1,8-naphthyridin-2-yl)diazene (1/1)

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    In the title compound, C5H8N3 +·C24H20B−·C20H18N6, the 1,2-bis­(5,7-dimethyl-1,8-naphthyridin-2-yl)diazene mol­ecule is essentially planar (r.m.s. deviation = 0.0045 Å) and aligned in nearly coplanar manner with the 2,6-diamino­pyridinium ion, making a dihedral angle of 5.19 (5)°. The diamino­pyridine mol­ecule is protonated on the central pyridine N atom and the B atom bears the counter-charge. The amine groups of the diamino pyridinium cation form intra­molecular N—H⋯N hydrogen bonds, resulting in linear and bent inter­actions with the naphthyridine ring system

    To the Theory of Ferrohydrodynamic Circulating Flow Induced by Running Magnetic Field

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    We present results of theoretical modeling of macroscopic circulating flow induced in a drop of ferrofluid by oscillating running magnetic field. The drop is placed in a narrow flat channel filled by a nonmagnetic liquid. The aim of this work is development of a scientific basis for a progressive method of address drug delivery to thrombus clots in blood vessels with the help of the magnetically induced circulation flow. Our results show that the oscillating running field allows inducing the carrier fluid flow with velocity amplitude 1–10 cm/s. This is the range of values, presenting interest from the point of view of the drug delivery. © 2020, EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature

    Field-induced circulation flow in magnetic fluids

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    In this paper, we present results of a theoretical study of circulation flow in ferrofluids under the action of an alternating inhomogeneous magnetic field. The results show that the field with the amplitude of about 17 kA m−1 and angular frequency 10 s−1 can induce mesoscopic flow with a velocity amplitude of about 0.5 mm s−1. This mechanism can be used for intensification of drag delivery in blood vessels. © 2020 The Author(s) Published by the Royal Society. All rights reserved.Agence Nationale de la Recherche, ANRMinistry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2020-005119-31-90003, 18-08-00178, 20-02-00022Data accessibility. This article has no additional data. Authors’ contributions. P.K. and G.V.-D.: the physical idea of the study. A.Z.: mathematical model. A.M. and M.R.-M.: calculations. Competing interests. We declare we have no competing interests. Funding. The work was supported by the Russian Fund of Basic Researches, projects 18-08-00178, 19-31-90003 and 20-02-00022; by the programme of the Ministry of Education and Science of the Russian Federation, project FEUZ-2020-0051; by French ‘Agence Nationale de la Recherche’, Project Future Investments UCA JEDI, No. ANR-15-IDEX-01 (projects ImmunoMag and MagFilter) and by the private company Axlepios Biomedicals

    Europe Needs Consistent Teaching of the Economics of Animal Health

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    The prevalence of meat consumption dictates that there is a global need for people educated in animal health economics. Since there are limited resources available for animal health surveillance, as well as the control and prevention of diseases, people skilled in animal health science with a deep understanding of economics and the allocation of scarce resources are required to enable consumer to access safe, value-added meat product

    Kinetics of field-induced phase separation of a magnetic colloid under rotating magnetic fields

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    This paper is focused on the experimental and theoretical study of the phase separation of a magnetic nanoparticle suspension under rotating magnetic fields in a frequency range, 5 Hz ≤ ν ≤ 25 Hz, relevant for several biomedical applications. The phase separation is manifested through the appearance of needle-like dense particle aggregates synchronously rotating with the field. Their size progressively increases with time due to the absorption of individual nanoparticles (aggregate growth) and coalescence with neighboring aggregates. The aggregate growth is enhanced by the convection of nanoparticles toward rotating aggregates. The maximal aggregate length, Lmax ∝ ν-2, is limited by fragmentation arising as a result of their collisions. Experimentally, the aggregate growth and coalescence occur at a similar timescale, ∼1 min, weakly dependent on the field frequency. The proposed theoretical model provides a semi-quantitative agreement with the experiments on the average aggregate size, aggregation timescale, and size distribution function without any adjustable parameter. © 2020 Author(s).We are grateful to Dr. A. Bee and Dr. D. Talbot from PHENIX laboratory at Sorbonne University (Paris, France) for providing us with the parent ferrofluid. P.K. acknowledges the French “Agence Nationale de la Recherche,” Project Future Investments UCA JEDI, Grant No. ANR-15-IDEX-01 (projects ImmunoMag and MagFilter) and the private company Axlepios Biomedical for financial support, and J.Q.C. acknowledges the financial support of UCA JEDI and Axlepios Biomedical through the PhD fellowship. A.Z. thanks the Russian Science Foundation, Project No. 20-12-00031, for financial support

    Nonlinear theory of macroscopic flow induced in a drop of ferrofluid

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    We present results of theoretical modelling of macroscopic circulating flow induced in a cloud of ferrofluid by an oscillating magnetic field. The cloud is placed in a cylindrical channel filled by a nonmagnetic liquid. The aim of this work is the development of a scientific basis for a progressive method of addressing drug delivery to thrombus clots in blood vessels with the help of the magnetically induced circulation flow. Our results show that the oscillating field can induce, inside and near the cloud, specific circulating flows with the velocity amplitude about several millimetres per second. These flows can significantly increase the rate of transport of the molecular non-magnetic impurity in the channel. This article is part of the theme issue 'Transport phenomena in complex systems (part 1)'. © 2021 The Author(s).Agence Nationale de la Recherche, ANR: ANR-15-IDEX-01; Russian Science Foundation, RSF: 20-12-00031Data accessibility. Source code and numerical data has been provided as electronic supplementary material. Authors’ contributions. A.Y.Z. and P.K. were involved in problem statement and development of the mathematical model. D.C., M.R.M. and G.V.D. were involved in analytical and numerical calculations. Competing interests. We declare we have no competing interests Funding. A.Z. and D.C. thanks the Russian Science Foundation, project 20-12-00031, for the financial support. P.K. and M.R.M. thank the funding of French ‘Agence Nationale de la Recherche’, Project Future Investments UCA JEDI, No. ANR-15-IDEX-01 (projects ImmunoMag and MagFilter) and by the private company Axlepios Biomedical

    Spinal trigeminal neurons demonstrate an increase in responses to dural electrical stimulation in the orofacial formalin test

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    Primary headaches are often associated with pain in the maxillofacial region commonly classified under the term “orofacial pain” (OFP). In turn, long-lasting OFP can trigger and perpetuate headache as an independent entity, which is able to persist after the resolution of the main disorder. A close association between OFP and headache complicates their cause and effect definition and leads to misdiagnosis. The precise mechanisms underlying this phenomenon are poorly understood, partly because of the deficiency of research-related findings. We combined the animal models of OFP and headache—the orofacial formalin test and the model of trigeminovascular nociception—to investigate the neurophysiological mechanisms underlying their comorbidity. In anesthetized rats, the ongoing activity of single convergent neurons in the spinal trigeminal nucleus was recorded in parallel to their responses to the electrical stimulation of the dura mater before and after the injection of formalin into their cutaneous receptive fields. Subcutaneous formalin resulted not only in the biphasic increase in the ongoing activity, but also in an enhancement of neuronal responses to dural electrical stimulation, which had similar time profile. These results demonstrated that under tonic pain in the orofacial region a nociceptive signaling from the dura mater to convergent trigeminal neurons is significantly enhanced apparently because of the development of central sensitization; this may contribute to the comorbidity of OFP and headache
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