Conduction Block in the Peripheral Nervous System in Experimental Allergic Encephalomyelitis

Experimental Allergic Encephalomyelitis (EAE) has been widely studied as a model of multiple sclerosis, a central nervous system (CNS) disease of unknown aetiology. The clinical features of both EAE and multiple sclerosis provide the only guide to the progress and severity of these diseases, and are used to assess the response to treatment. In such comparisons the clinical features of EAE are assumed to be due to lesions in the CNS, but in this disease there is also histological evidence of damage to the peripheral nervous system (1-8). However, the functional consequences of such peripheral lesions have been entirely ignored. To examine this, we have studied nerve conduction in rabbits with EAE. We report here that most of the large diameter afferent fibres are blocked in the region of the dorsal root ganglion and at the dorsal root entry zone, thus accounting for the loss of tendon jerks and also, through the severe loss of proprioceptive information, the ataxia of thse animals. We conclude that whenever clinical comparisons are made between EAE and multiple sclerosis, the pathophysiology associated with histological damage of the peripheral nervous system must be taken into account

The Pathophysiology of Acute Experimental Allergic Encephalomyelitis in the Rabbit

Clinical, histological and electrophysiological studies were performed on rabbits with acute experimental allergic encephalomyelitis (EAE). The clinical features were similar to those previously described, with the notable exception of the new findings of areflexia, respiratory slowing and hypothermia. The histological findings were also similar to those previously reported, with inflammatory demyelinating lesions both in the central and peripheral nervous system, especially the dorsal root ganglia. Electrophysiological studies performed one to nine days after the onset of neurological signs demonstrated conduction block in a high proportion of the large diameter afferents in the lumbosacral and thoracic dorsal root ganglia. Single fibre studies with spike-triggered averaging confirmed the conduction block in the dorsal root ganglia. That the conduction block was due to demyelination was indicated by slowing of conduction in large diameter fibres, normal conduction in unmyelinated fibres and the specific effects of temperature and of the potassium channel blocking agent, 4-aminopyridine. These conduction abnormalities in the peripheral nervous system, focused on the dorsal root ganglia, account for the postural disturbance, hypotonia, ataxia and areflexia in rabbits with EAE. Such conduction block is likely to mask the expression of any lesions of the central nervous system that alone could produce similar signs. The implications of these findings for the human demyelinating diseases are discussed

Effects of Process Variables and Size Scale on Solidification Microstructure in Laser-Based Solid Freeform Fabrication of Ti-6Al-4V

Mechanical Engineerin

Incoherent dynamics in neutron-matter interaction

Coherent and incoherent neutron-matter interaction is studied inside a recently introduced approach to subdynamics of a macrosystem. The equation describing the interaction is of the Lindblad type and using the Fermi pseudopotential we show that the commutator term is an optical potential leading to well-known relations in neutron optics. The other terms, usually ignored in optical descriptions and linked to the dynamic structure function of the medium, give an incoherent contribution to the dynamics, which keeps diffuse scattering and attenuation of the coherent beam into account, thus warranting fulfilment of the optical theorem. The relevance of this analysis to experiments in neutron interferometry is briefly discussed.Comment: 15 pages, revtex, no figures, to appear in Phys. Rev.

Loss of redundant gene expression after polyploidization in plants

Based on chromosomal location data of genes encoding 28 biochemical systems in allohexaploid wheat,Triticum aestivum L. (genomes AABBDD), it is concluded that the proportions of systems controlled by triplicate, duplicate, and single loci are 57%, 25%, and 18% respectively

Photon Shot Noise Dephasing in the Strong-Dispersive Limit of Circuit QED

We study the photon shot noise dephasing of a superconducting transmon qubit in the strong-dispersive limit, due to the coupling of the qubit to its readout cavity. As each random arrival or departure of a photon is expected to completely dephase the qubit, we can control the rate at which the qubit experiences dephasing events by varying \textit{in situ} the cavity mode population and decay rate. This allows us to verify a pure dephasing mechanism that matches theoretical predictions, and in fact explains the increased dephasing seen in recent transmon experiments as a function of cryostat temperature. We investigate photon dynamics in this limit and observe large increases in coherence times as the cavity is decoupled from the environment. Our experiments suggest that the intrinsic coherence of small Josephson junctions, when corrected with a single Hahn echo, is greater than several hundred microseconds.Comment: 5 pages, 4 figures; includes Supporting Online Material of 6 pages with 5 figure

Plasticity reveals hidden resistance to extinction under climate change in the global hotspot of salamander diversity

Extinction rates are predicted to rise exponentially under climate warming, but many of these predictions ignore physiological and behavioral plasticity that might buffer species from extinction. We evaluated the potential for physiological acclimatization and behavioral avoidance of poor climatic conditions to lower extinction risk under climate change in the global hotspot of salamander diversity, a region currently predicted to lose most of the salamander habitat due to warming. Our approach integrated experimental physiology and behavior into a mechanistic species distribution model to predict extinction risk based on an individual’s capacity to maintain energy balance with and without plasticity. We assessed the sensitivity of extinction risk to body size, behavioral strategies, limitations on energy intake, and physiological acclimatization of water loss and metabolic rate. The field and laboratory experiments indicated that salamanders readily acclimatize water loss rates and metabolic rates in ways that could maintain positive energy balance. Projections with plasticity reduced extinction risk by 72% under climate warming, especially in the core of their range. Further analyses revealed that juveniles might experience the greatest physiological stress under climate warming, but we identified specific physiological adaptations or plastic responses that could minimize the lethal physiological stress imposed on juveniles. We conclude that incorporating plasticity fundamentally alters ecological predictions under climate change by reducing extinction risk in the hotspot of salamander diversity

An analytic expression for the electronic correlation term of the kinetic functional

We propose an analytic formula for the non-local Fisher information functional, or electronic kinetic correlation term, appearing in the expression of the kinetic density functional. Such an explicit formula is constructed on the basis of well-founded physical arguments and a rigorous mathematical prescription

A proteomic approach for the rapid, multi-informative and reliable identification of blood

Blood evidence is frequently encountered at the scene of violent crimes and can provide valuable intelligence in the forensic investigation of serious offences. Because many of the current enhancement methods used by crime scene investigators are presumptive, the visualisation of blood is not always reliable nor does it bear additional information. In the work presented here, two methods employing a shotgun bottom up proteomic approach for the detection of blood are reported; the developed protocols employ both an in solution digestion method and a recently proposed procedure involving immobilization of trypsin on hydrophobin Vmh2 coated MALDI sample plate. The methods are complementary as whilst one yields more identifiable proteins (as biomolecular signatures), the other is extremely rapid (5 minutes). Additionally, data demonstrate the opportunity to discriminate blood provenance even when two different blood sources are present in a mixture. This approach is also suitable for old bloodstains which had been previously chemically enhanced, as experiments conducted on a 9-year-old bloodstain deposited on a ceramic tile demonstrate