A potentially powerful information processing strategy in the brain is to take advantage of the temporal structure of neuronal spike trains. An increase in synchrony within the neural representation of an object or location increases the efficacy of that neural representation at the next synaptic stage in the brain; thus, increasing synchrony is a candidate for the neural correlate of attentional selection. We investigated the synchronous firing of pairs of neurons in the secondary somatosensory cortex (SII) of three monkeys trained to switch attention between a visual task and a tactile discrimination task. We found that most neuron pairs in SII cortex fired synchronously and, furthermore, that the degree of synchrony was affected by the monkey's attentional state. In the monkey performing the most difficult task, 35% of neuron pairs that fired synchronously changed their degree of synchrony when the monkey switched attention between the tactile and visual tasks. Synchrony increased in 80% and decreased in 20% of neuron pairs affected by attention.

Maintaining close proximity between the electrode array and the retinal surface is critical in developing a successful retinal implant. With the development of chronic electrode arrays that are stable and flush on the retinal surface, it is likely that the influence of other factors such as electrode size, retinal degeneration, and subject age will become more apparent. (ClinicalTrials.gov number, NCT00279500.).

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Quantum mechanics is compatible with scenarios where the relative order between two events can be indefinite. Here we show that two independent instances of a noisy process can behave as a perfect quantum communication channel when used in a coherent superposition of two alternative orders. This phenomenon occurs even if the original process has zero capacity to transmit quantum information. In contrast, perfect quantum communication does not occur when the message is sent directly from the sender to the receiver through a superposition of alternative paths, with an independent noise process acting on each path. The possibility of perfect quantum communication through independent noisy channels highlights a fundamental difference between the superposition of orders in time and the superposition of paths in space.

The high degree of microbial diseases and their multidrug resistant properties make the researchers to develop new class of antimicrobial agents. A modern and innovative approach of drug development is the use of metallic nanoparticles as new formulations of antimicrobial agents. In this study, microwave irradiated CaO nanoparticles (CaO-NPs) were used to determine their antimicrobial efficacy against gram negative and gram positive bacteria, as well as pathogenic yeast. The physiochemical properties of CaO-NPs were characterized by means of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). The nanoparticles consist of well dispersed agglomerates of grains with a narrow size distribution of 14-24 nm. The prepared CaO-NPs showed much higher antimicrobial activity against Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus epidermidis (MTCC 435) in comparision to Candida tropicalis (NCIM 3110). The minimum inhibitory concentration (MIC) value of CaO-NPs was found within the range of 2-8 mM for all the above tested strains. This bioactive nanoparticle also inhibits the biofilm formation and may have future applications cheap and non toxic as antimicrobial drug for skin care product development.

Antibacterial activity of hot aqueous and methanolic extracts prepared from six plants (Terminallia chebula, Terminallia bellerica, Phyllanthus emblica, Punica granatum, Lawsonia alba and Mikania micrantha) used in traditional folk medicines of India were screened against five pathogenic bacteria (Staphylococcus aureus MTCC 2940, Bacillus subtilis MTCC 441, Escherichia coli MTCC 739, Proteus vulgaris MTCC 426 and Enterobacter aerogenes MTCC 111). The highest antibacterial potentiality was exhibited by the methanolic leaf extract of T. chebula, followed by the aqueous fruit extract of T. bellerica. The leaf extract of T. chebula can be considered to be as equally potent as the most effective antibiotics, such as ciprofloxacin, gentamycin, kanamycin, ofloxacin and cephalexin. A sensitivity test performed with commonly used sensitivity test disks resulted in the appearance of multiple drug resistance phenotypes of the bacteria tested. A comparison of data in the inhibition zones of pathogenic bacteria showed that gentamycin, ofloxacin, kanamycin and tobramycin were effective against all of the bacterial strains tested.

Citation: Caspi A, Roy A, Dorn JD, Greenberg RJ. Retinotopic to spatiotopic mapping in blind patients implanted with the Argus II retinal prosthesis. Invest Ophthalmol Vis Sci. 2017;58:119-127. DOI:10.1167/ iovs.16-20398 PURPOSE. To quantify the precision of mapping from retinotopic (retina-centered) to spatiotopic (world-centered) coordinates in blind humans implanted with a retinal prosthesis device. Additionally, to demonstrate that an eye tracker can be calibrated on sightless patients based on the percept from a visual implant. METHODS.We directly activated epiretinal electrodes to create retinotopic stimuli and recorded the location of the percept at world-based coordinates. In contrast to normal Argus II use where stimulation is a function of the captured scene's image, in this research we directly controlled the waveform in each electrode and measured the percept's location using a trackable handheld marker. For eye tracking, pupil images were recorded with a timestamp synchronized to the stimulation and marker positions. RESULTS.Remapping of the measured world locations to the position of the electrodes on the retina is feasible by accounting for eye orientation at the onset of stimulation. Transformation of pupil images to the eye's orientation (i.e., eye tracker calibration) can be done by solving for the variables that minimize the spread of the remapped retinal electrode locations. After mapping to retinal coordinates based on eye positions, the measured precision of pointing was 28 to 38, which is comparable to open-loop pointing in sighted individuals.CONCLUSIONS. The brain accurately maps the artificial vision induced by a retinal prosthesis based on instantaneous gaze position. Remapping based on eye position is feasible and will increase visual stability in prosthetic vision.