The two-spin model of a tracking chamber: a phase-space perspective

We study the dynamics of classical localization in a simple, one-dimensional model of a tracking chamber. The emitted particle is represented by a superposition of Gaussian wave packets moving in opposite directions, and the detectors are two spins in fixed, opposite positions with respect to the central emitter. At variance with other similar studies, we give here a phase-space representation of the dynamics in terms of the Wigner matrix of the system. This allows a better visualization of the phenomenon and helps in its interpretation. In particular, we discuss the relationship of the localization process with the properties of entanglement possessed by the system.

Usual or unusual presentations of Dirofilaria repens in two sibling dogs: a case report

This study describes two different manifestations of Dirofilaria repens infection in sibling dogs with microfilaremia. Dog 1, asymptomatic, harbored a gravid female of D. repens on the parietal layer of tunica vaginalis of one testicle and showed a marked circulating eosinophilia (3.3·103/μL). Both testicles were normal in shape and size without any gross lesions. Dog 2 had a pyotraumatic dermatitis. The cases were confirmed by PCR and sequencing. The sequences obtained showed 100% identity with those of D. repens isolated from human scrotum in Croatia. The treatment with moxidectin 2.5% and imidacloprid 10%/kg was effective in eliminating microfilariae after just one application, as demonstrated by negative modified Knott’s tests and PCR analyses of blood samples. This status was maintained during the post-treatment observation period. The classical localization of D. repens in dogs is in subcutaneous tissues, within nodules or free; however, it can also occur with some frequency in testicles, as described in humans. The infection can be associated with circulating eosinophilia or pyotraumatic dermatitis, as reported in this study. Thus, in endemic areas, it is advisable to carefully inspect the removed testicles at neutering since parasite localization can take place without any macroscopic changes. Moreover, in the case of circulating eosinophilia or pyotraumatic dermatitis, investigations should include modified Knott’s test and PCR to ensure that D. repens is not the cause of these alterations. Rapid and sensitive tests for the early detection of infected animals would help to prevent or limit the spread of this zoonosis.

Novel Strategies for Glutamate Clearance in the Glia-Deprived Synaptic Hub of C. elegans

Brain function requires the ability to form neuronal circuits that mediate focused and accurate communication. Since the vast majority of brain synapses use Glutamate (Glu) as their neurotransmitter, unintended spillover of Glu between adjacent synapses is a critical challenge. To ensure accurate neurotransmission and avert synaptic mix-up, specialized Glu Transporters (GluTs) clear the synapse of released Glu. While classical views of neuronal morphology and physiology depict isolated spiny synapses enwrapped by GluT-expressing glia, in reality, a considerable portion of synapses are flat, glial coverage in some parts of the brain is rather sparse, and extracellular space is larger than previously estimated. This suggests that diffusion in interstitial fluids might have an important role in Glu clearance in these synapses. To understand basic principles of Glu clearance in flat-, glia-deprived synapses, we study the physiology of neuronal circuits in the C. elegans nerve ring, the nematode’s aspiny synaptic hub. We use behavioral assays, Ca2+ imaging, and iGluSnFR to follow synaptic activity in intact animals. We find that synapses in a nociceptive avoidance circuit are dramatically affected by distal GluTs, while an adjacent chemoattraction circuit is controlled by proximal GluTs. We also find that pharyngeal pulsatility and mobility, which could agitate interstitial fluids, are critical for synaptic physiology. We therefore conclude that robust Glu clearance in the nematode is provided differentially by distal and proximal GluTs, aided by agitation of interstitial fluids. Such principles might be informative in determining additional factors that contribute to robust Glu clearance in other neuronal systems.Significance StatementThe nervous system depends on faithful relay of information without inadvertent mixing of signals between neuronal circuits. Classical views of the nervous system depict isolated synapses, enwrapped by glia that express neurotransmitter-transporters. However, this view is incomplete, since many synapses are flat, deprived of glia, and exposed to a larger-than-expected extracellular space. We use optogenetic tools to investigate glutamate clearance strategies in the aspiny and glia-deprived synaptic hub of intact nematodes. We find a division of labor among Glutamate transporters: while some transporters display classical localization near the synapses, others are distal, and cooperate with agitation of interstitial fluids to prevent glutamate accumulation. These novel principles might contribute to synaptic clearance in higher animals, affecting normal neuronal physiology and disease.

An Algorithm of Mobile Robot Node Location Based on Wireless Sensor Network

In the wireless sensor network, there is a consistent one-to-one match between the information collected by the node and the location of the node. Therefore, it attempts to determine the location of unknown nodes for wireless sensor networks. At present, there are many kinds of node localization methods. Because of the distance error, hardware level, application environment and application costs and other factors, the positioning accuracy of various node positioning methods is not in complete accord. The objective function is established and algorithm simulation experiments are carried out to make a mobile ronot node localization. The experimnettal results showed that the proposed algorithm can achieve higher localization precision in fewer nodes. In addition, the localization algorithm was compared with the classical localization algorithm. In conclusion, it is verified that the localization algorithm proposed in this paper has higher localization accuracy than the traditional classical localization algorithm when the number of nodes is larger than a certain number

QUANTUM NETWORK MODELS AND CLASSICAL LOCALIZATION PROBLEMS

A review is given of quantum network models in class C which, on a suitable 2d lattice, describe the spin quantum Hall plateau transition. On a general class of graphs, however, many observables of such models can be mapped to those of a classical walk in a random environment, thus relating questions of quantum and classical localization. In many cases it is possible to make rigorous statements about the latter through the relation to associated percolation problems, in both two and three dimensions.