7,150 research outputs found
The South Island dairy lameness group project
Lameness is an important issue wherever dairy production occurs. It is consistently
placed after infertility and mastitis in the top three cow health issues for farmers both
internationally and in New Zealand (NZ). It has been a commonly held view in the South Island (SI)
industry that there is more lameness here than in the North Island (NI), and that the problem has
been growing in recent years. There are strong opinions in the SI industry suggesting there are
important local influences on lameness.
This is often explained in reference to differences between the NI and SI climate, herds,
and management. The current SI herd has a cluster of features linked to the recent history of
dairying here. In the past 15 years there has been strong expansion of the NZ dairy industry into
the SI, where cheaper land and the availability of extensive, dependable irrigation have enabled
a sustained increase in the number of dairy farms and cows (Anonymous, 2006). Despite the
obvious similarities of grass based dairying between the NI and SI, there are several observed
differences. The average farm in the SI has a greater herd size and greater per cow and per
hectare production, and this high production is particularly pronounced in some regions (eg.
Canterbury). Over the period of expansion there has often been emphasis on increasing herd
size, which can reduce options around culling of cows. Many SI farms are conversions and
irrigation along with intensive, recent pasture refurbishment are common features. Pasture
management is often a top tier priority, and very intensive systems, to increase utilisation and
maintain high quality (high energy, low fibre) across the season are commonplace. In addition,
the long daylight hours and cooler nights are thought to promote higher sugar content in the
pastures.
Against that background, the origins of the most common and longstanding explanations
within the SI industry for high lameness - particularly the role of nutrition - can be better
understood. In brief summary, the popular idea of the influence of nutrition, the high energy and
low fibre pastures are thought to induce rumen dysfunction resulting in secondary weakness in
the hooves
Rumen function and lameness in South Island cows
A large part of the rumen research we use here in NZ is drawn from work done overseas, routinely on cows fed lots of grain, while there is perishingly
little hard data on the high production, grass based rumens that are the direction NZ dairy appears to
be heading in. Despite this, or maybe because of this, there are a considerable number of loud and
strong opinions around rumen function here in NZ, and particularly about the high producing cow.
Although it seems there are a lot of issues around rumen function spoken about, in reality there is just
one central theme that is most commonly discussed, and this is just recycled in different forms. This
paper will look at what we know, and don’t know, about rumen function in grass based dairy cows
under NZ conditions, and outline the results of the three years of rumen research on the Lincoln
University Dairy Farm (LUDF), and what this tells us about the role of the rumen in lameness here in
the South Island
Dominant BIN1-related centronuclear myopathy (CNM) revealed by lower limb myalgia and moderate CK elevation
We report a BIN1-related CNM family with unusual clinical phenotype. The proband, a 56-year-old man suffered of lower limbs myalgia since the age of 52. Clinical examination showed short stature, mild symmetric eyelid ptosis without ophthalmoplegia, scapular winging and Achilles tendon retraction. A muscle weakness was not noted. CK levels were up to 350 UI/L. Deltoid muscle biopsy showed nuclear centralization and clustering, deep sarcolemmal invaginations and type 1 fiber hypotrophy. Whole body MRI revealed fatty infiltration of posterior legs compartments, lumbar paraspinal and serratus muscles. Myotonic dystrophy type1 and 2, Pompe disease and MTM1 and DNM2-related CNM were ruled out. By sequencing BIN1, we identified a heterozygous pathogenic mutation [c.107C > A (p.A36E)], and we demonstrate that the mutation strongly impairs the membrane tubulation property of the protein. One affected sister carried the same mutation. Her clinical examination and muscle MRI revealed a similar phenotype. Our findings expand the clinical and genetic spectrum of the autosomal dominant CNM associated with BIN1 mutations
INTRODUCTION
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70110/2/PFLDAS-12-5-iii-1.pd
A real delivery problem dealt with Monte Carlo techniques
[EN] In this paper we use Monte Carlo Techniques to deal with a real world delivery problem of a food company in Valencia (Spain). The problem is modeled as a set of 11 instances of the well known Vehicle Routing Problem, VRP, with additional time constraints. Given that VRP is a NP-hard problem, a heuristic algorithm, based on Monte Carlo techniques, is implemented. The solution proposed by this heuristic algorithm reaches distance and money savings of about 20% and 5% respectively.This research was partially supported by MICINN, Project MTM2013-43540-P and by UPV, Project Programa de Apoyo a la Investigación y Desarrollo de la UPV PAID-06-12.S577181Fernández de Córdoba, P., L.M. García-Raffi and J.M. Sanchis Llopis (1998), A heuristic algorithm based on Monte Carlo methods for the Rural Postman Problem.Computers and Op. Research,25, No. 12, pp. 1097–1106, 1998.Fernández de Córdoba, P. and L.M. García-Raffi, E. Nieto and J.M. Sanchis Llopis (1999a), Aplicación de técnicas Monte Carlo a un problema real de Rutas de Vehículos.Anales de Ingeniería, Colombia. In press.Fernández de Córdoba, P., L.M. García-Raffi and J.M. Sanchis Llopis (1999b), A Constructive Parallel Algorithm based on Monte Carlo techniques for Routing Problems, Submitted toParallel Computers.Laporte, G. (1992), The Vehicle Routing Problem: an overview of exact and approximate algorithms,European Journal of Operations Research,59, 345.Laporte, G., M. Desrochers and Y. Nobert (1985), “Optimal Routing under Capacity and Distance Restrictions.Operations Research,33, pp. 1050–1073.Laporte G. and Y. Nobert (1987), Exact algorithms for The Vehicle Routing Problem,Surveys in Combinatorial Optimization (S. Martello, G. Laporte, M. Minoux and C. Ribeiro Eds.). North-HollandAmsterdamMayado, A. (1998), Organización de los itinerarios de la flota de camiones de reparto de una sociedad cooperativa. Optimización mediante técnicas de simulación Monte Carlo. Proyecto Fin de Carrera. E.T.S.I.I. Universidad Politécnica de Valencia
Environment of the submillimeter-bright massive starburst HFLS3 at z∼6.34
We describe the search for Lyman break galaxies (LBGs) near the submillimeter-bright starburst galaxy HFLS3 at z = 6.34 and a study on the environment of this massive galaxy during the end of reionization. We performed two independent selections of LBGs on images obtained with the Gran Telescopio Canarias (GTC) and the Hubble Space Telescope (HST) by combining nondetections in bands blueward of the Lyman break and color selection. A total of 10 objects fulfilling the LBG selection criteria at z > 5.5 were selected over the 4.54 and 55.5 arcmin^2 covered by our HST and GTC images, respectively. The photometric redshift, UV luminosity, and star formation rate of these sources were estimated with models of their spectral energy distribution. These z ~ 6 candidates have physical properties and number densities in agreement with previous results. The UV luminosity function at z ~ 6 and a Voronoi tessellation analysis of this field show no strong evidence for an overdensity of relatively bright objects (m_(F105W) < 25.9) associated with HFLS3. However, the overdensity parameter deduced from this field and the surface density of objects cannot exclude definitively the LBG overdensity hypothesis. Moreover, we identified three faint objects at less than 3'' from HFLS3 with color consistent with those expected for z ~ 6 galaxies. Deeper data are needed to confirm their redshifts and to study their association with HFLS3 and the galaxy merger that may be responsible for the massive starburst
Impacts of misalignment effects on the Muon Spectrometer Performance
The ATLAS detector, currently being installed at CERN, is designed to exploit the full potential of the LHC, identifying and providing highly accurate energy and momentum measurements of particles emerging from the LHC protonproton collisions with a centre-of-mass energy at 14 TeV, starting in 2007. High-momentum final-state muons are among the most promising signatures at the LHC, thanks to a high-resolution Muon Spectrometer with standalone triggering and momentum measurement. As well known, muons interact primarily trough their electromagnetic charge, but since they are 200 times more massive than the electrons they are less affected by the electric fields of the nuclei they encounter. Muons with an energy of more than a few GeV penetrate the calorimeter and can reach the Muon Spectrometer, which consists out of more than 1.200 single drift-tubes chambers. The correct alignment of the ATLAS Muon Spectrometer is crucial to ensure its design performance. This note documents the first attempt at using various misaligned Muonspectrometer layouts to study their impacts Muon Spectrometer performance
Compliance error compensation in robotic-based milling
The paper deals with the problem of compliance errors compensation in
robotic-based milling. Contrary to previous works that assume that the
forces/torques generated by the manufacturing process are constant, the
interaction between the milling tool and the workpiece is modeled in details.
It takes into account the tool geometry, the number of teeth, the feed rate,
the spindle rotation speed and the properties of the material to be processed.
Due to high level of the disturbing forces/torques, the developed compensation
technique is based on the non-linear stiffness model that allows us to modify
the target trajectory taking into account nonlinearities and to avoid the
chattering effect. Illustrative example is presented that deals with
robotic-based milling of aluminum alloy
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