1,967 research outputs found
Some aspects of the pathology and pathogenesis of bovine tuberculosis (and other published papers)
BOVINE TUBERCULOSIS:
(1) Introduction
(2) Pathogenesis of bovine tuberculosis as
based on abattoir records
(3) Distribution of the bronchial tree in
the bovine lung
(4) Bovine pulmonary tuberculosis -
(a) Primary infection; (b) Phthisis
(5) Tuberculosis of the bovine udder
(6) All outbreak of bovine tuberculosis due
to udder irrigation
(7) References.ABORTION IN SHEEP:
(1) Introduction
(2) Enzootic abortion in ewes. Reprint
(3) Developmental forms of the virus of
ovine enzootic abortion.
(4) Enzootic abortion in ewes and the
complement fixation test.
(5) Enzootic abortion in ewes.
Immunisation and infection experiments.
(6) Tick borne fever as a cause of abortion
in sheep.
(7) ReferencesMIISCELLANEOUS PUBLICATIONS:
(1) Bovine tuberculosis - incorporating a
review of John Francis' book.
(2) A field trial of M42 (D.D.T.) dip in
the control of sheep myiasis.
(3) A disease survey of Sourhope Farm
The Corporate-Consumer Power Dynamic Operating Behind the International Intellectual Property Regime: An Intractable Development Model with Uneven Results
The corporate-consumer power dynamic operating behind the international intellectual property regime has created a development model that perpetuates the hegemonic power of corporate elites and their governmental agents at the expense of developing nations. The inequity of the regime seems to be rooted in the paradoxical delegation of exclusive intellectual property rights to private corporate interests who dispense knowledge as a global public good. However, the inequality actually begins with the inception of knowledge itself and is the consequence of natural exclusivity over oneâs own thoughts and creations, including how those ideas are conveyed to the public sphere. The freedom to pool individual ideas and resources into corporate structures, combined with the propagation of consumerism, has led to remarkable innovations, but it has also facilitated the concentration of corporate power and the projection of that power abroad. Propelled by this power dynamic, multinational corporations have successfully lobbied for the international restriction of knowledge as a global public good, thereby frustrating attempts to promote a more equitable development model. Nevertheless, an understanding of how the corporate-consumer dynamic operates can help advance potential solutions to address the inequities, while at the same time retaining the beneficial aspects of the regime. By fostering an enlightened global citizenship that is more consistent with public works projects, a new corporate ethic may begin to acknowledge sustainable development goals and embrace a more equitable distribution of global public goods over the long term
Quantum spin glass in anisotropic dipolar systems
The spin-glass phase in the \LHx compound is considered. At zero transverse
field this system is well described by the classical Ising model. At finite
transverse field deviations from the transverse field quantum Ising model are
significant, and one must take properly into account the hyperfine
interactions, the off-diagonal terms in the dipolar interactions, and details
of the full J=8 spin Hamiltonian to obtain the correct physical picture. In
particular, the system is not a spin glass at finite transverse fields and does
not show quantum criticality.Comment: 6 pages, 2 figures, to appear in J. Phys. Condens. Matter
(proceedings of the HFM2006 conference
Genetic structure and history of Swiss maize ( Zea mays L. ssp. mays ) landraces
Between 1930 and 2003 with emphasis on the 1940s maize landraces (Zea mays L. ssp. mays) from all over Switzerland were collected for maintenance and further use in a new Swiss breeding program. The genetic relationship and diversity among these accessions stored in the Swiss gene bank is largely unknown. Our hypothesis was that due to the unique geographic, climatic, and cultural diversity in Switzerland a diverse population of maize landraces had developed over the past three centuries. The aims were to characterize the genetic diversity of the Swiss landraces and their genetic relationship with accessions from neighbouring regions as well as reviewing their history, collection, and maintenance. The characterization and grouping was based on analyses with ten microsatellite markers. Geographic, cultural, and climatic conditions explained a division in two distinct groups of accessions. One group consisted of landraces collected in the southern parts of Switzerland. This group was related to the Italian Orange Flints. The other group contained accessions from northern Switzerland which were related to Northern European Flints in particular German Flints. Historic evidence was found for a frequent exchange of landraces within the country resulting in a lack of region-specific or landrace-specific genetic groups. The relatively large separation between the accessions, indicated by high F ST (0.42), might be explained partly by a bottleneck during the collection and maintenance phase as well as by geographical and cultural separation of north and south of the country. Due to the high genetic diversity, the accessions here are a potential resource for broadening the European flint poo
'Hole-digging' in ensembles of tunneling Molecular Magnets
The nuclear spin-mediated quantum relaxation of ensembles of tunneling
magnetic molecules causes a 'hole' to appear in the distribution of internal
fields in the system. The form of this hole, and its time evolution, are
studied using Monte Carlo simulations. It is shown that the line-shape of the
tunneling hole in a weakly polarised sample must have a Lorentzian lineshape-
the short-time half-width in all experiments done so far should be
, the half-width of the nuclear spin multiplet. After a time
, the single molecule tunneling relaxation time, the hole width begins
to increase rapidly. In initially polarised samples the disintegration of
resonant tunneling surfaces is found to be very fast.Comment: 4 pages, 5 figure
Marine Evidence-based Sensitivity Assessment (MarESA) â A Guide
The Marine Evidence-based Sensitivity Assessment (MarESA) methodology was developed by the Marine Life Information Network (MarLIN) team at the Marine Biological Association of the UK. The following guide details the approach, its assumptions, and its application to sensitivity assessment.
The guide discusses:
⢠key terms used in sensitivity assessment;
⢠the definitions and terms used in the MarESA approach;
⢠its assumptions;
⢠the definition of resistance, resilience and sensitivity;
⢠the definition of pressures and their benchmarks;
⢠the step by step process by which the possible sensitivity of each feature (habitat, biotope or species) to each pressure is assessed;
⢠the interpretation and application of evidence to sensitivity assessments on a pressure by pressure basis; and
⢠limitations in the application of sensitivity assessments in management.
The MarESA methodology provides a systematic process to compile and assess the best available scientific evidence to determine each sensitivity assessment. The evidence used is documented throughout the process to provide an audit trail to explain each sensitivity assessment. Unlike other expert-based approaches, this means that the MarESA assessments can be repeated and updated.
The resultant 'evidence base' is the ultimate source of information for the application of the sensitivity assessments to management and planning decisions. The MarESA dataset and MarLIN website represent the largest review of the potential effects of human activities and natural events on the marine and coastal habitats of the North East Atlantic yet undertaken
Remarks on the k-error linear complexity of p(n)-periodic sequences
Recently the first author presented exact formulas for the number of 2âżn-periodic binary sequences with given 1-error linear complexity, and an exact formula for the expected 1-error linear complexity and upper and lower bounds for the expected k-error linear complexity, k >2, of a random 2âżn-periodic binary sequence. A crucial role for the analysis played the Chan-Games algorithm. We use a more sophisticated generalization of the Chan-Games algorithm by Ding et al. to obtain exact formulas for the counting function and the expected value for the 1-error linear complexity for pâżn-periodic sequences over Fp, p prime. Additionally we discuss the calculation of lower and upper bounds on the k-error linear complexity of pâżn-periodic sequences over Fp
Quantum Relaxation of Magnetisation in Magnetic Particles
At temperatures below the magnetic anisotropy energy, monodomain magnetic
systems (small particles, nanomagnetic devices, etc.) must relax quantum
mechanically. This quantum relaxation must be mediated by the coupling to both
nuclear spins and phonons (and electrons if either particle or substrate is
conducting. We analyze the effect of each of these couplings, and then combine
them. Conducting systems can be modelled by a "giant Kondo" Hamiltonian, with
nuclear spins added in as well. At low temperatures, even microscopic particles
on a conducting substrate (containing only spins) will have their
magnetisation frozen over millenia by a combination of electronic dissipation
and the "degeneracy blocking" caused by nuclear spins. Raising the temperature
leads to a sudden unblocking of the spin dynamics at a well defined
temperature. Insulating systems are quite different. The relaxation is strongly
enhanced by the coupling to nuclear spins. At short times the magnetisation of
an ensemble of particles relaxes logarithmically in time, after an initial very
fast decay; this relaxation proceeds entirely via the nuclear spins. At longer
times phonons take over, but the decay rate is still governed by the
temperature-dependent nuclear bias field acting on the particles - decay may be
exponential or power-law depending on the temperature. The most surprising
feature of the results is the pivotal role played by the nuclear spins. The
results are relevant to any experiments on magnetic particles in which
interparticle dipolar interactions are unimportant. They are also relevant to
future magnetic device technology.Comment: 30 pages, RevTex, e:mail , Submitted to J.Low
Temp.Phys. on 1 Nov. 199
Quantum Barkhausen Noise Induced by Domain Wall Co-Tunneling
Most macroscopic magnetic phenomena (including magnetic hysteresis) are
typically understood classically. Here, we examine the dynamics of a uniaxial
rare-earth ferromagnet deep within the quantum regime, so that domain wall
motion, and the associated hysteresis, is dominated by large-scale quantum
tunneling of spins, rather than classical thermal activation over a potential
barrier. The domain wall motion is found to exhibit avalanche dynamics,
observable as an unusual form of Barkhausen noise. We observe non-critical
behavior in the avalanche dynamics that only can be explained by going beyond
traditional renormalization group methods or classical domain wall models. We
find that this ``quantum Barkhausen noise'' exhibits two distinct mechanisms
for domain wall movement, each of which is quantum-mechanical, but with very
different dependences on an external magnetic field applied transverse to the
spin (Ising) axis. These observations can be understood in terms of the
correlated motion of pairs of domain walls, nucleated by co-tunneling of
plaquettes (sections of domain wall), with plaquette pairs correlated by
dipolar interactions; this correlation is suppressed by the transverse field.
Similar macroscopic correlations may be expected to appear in the hysteresis of
other systems with long-range interactions.Comment: 11 pages, 4 figure
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