Model-based prediction of optogenetic sound encoding in the human cochlea by future optical cochlear implants

When hearing fails, electrical cochlear implants (eCIs) partially restore hearing by direct stimulation of spiral ganglion neurons (SGNs). As light can be better confined in space than electrical current, optical CIs (oCIs) provide more spectral information promising a fundamental improvement of hearing restoration by cochlear implants. Here, we turned to computer modelling for predicting the outcome of optogenetic hearing restoration by future oCIs in humans. We combined three-dimensional reconstruction of the human cochlea with ray-tracing simulation of emission from LED or laser-coupled waveguide emitters of the oCI. Irradiance was read out at the somata of SGNs. The irradiance values reached with waveguides were about 14 times higher than with LEDs, at the same radiant flux of the emitter. Moreover, waveguides outperformed LEDs regarding spectral selectivity. oCIs with either emitter type showed greater spectral selectivity when compared to eCI. In addition, modeling the effects of the source-to-SGN distance, orientation of the sources and impact of scar tissue further informs the development of optogenetic hearing restoration

Live Demonstration: Multiplexing AER Asynchronous Channels over LVDS Links with Flow-Control and Clock- Correction for Scalable Neuromorphic Systems

In this live demonstration we exploit the use of a serial link for fast asynchronous communication in massively parallel processing platforms connected to a DVS for realtime implementation of bio-inspired vision processing on spiking neural networks

Astrin regulates Aurora-A localization

Alterations in the expression and activity of the centrosomal kinase, Aurora-A/STK15, affect genomic stability, disrupt the fidelity of centrosome duplication, and induce cellular transformation. A mitotic spindle-associated protein, astrin/DEEPEST, was identified as an Aurora-A interacting protein by a two-hybrid screen. Astrin and Aurora-A co-express at mitosis and co-localize to mitotic spindles. RNAi-mediated depletion of astrin abolishes the localization of Aurora-A on mitotic spindles and leads to a moderate mitotic cell cycle delay, which resembles the mitotic arrest phenotypes in siAurora-A treated cells. However, depletion of Aurora-A does not affect astrin localization, and co-depletion of both astrin and Aurora-A causes a mitotic arrest phenotype similar to depletion of siAurora-A alone. These results suggest that astrin acts upstream of Aurora-A to regulate its mitotic spindle localization

The Dwarf Novae of Shortest Period

We present observations of the dwarf novae GW Lib, V844 Her, and DI UMa. Radial velocities of H-alph yield orbital periods of 0.05332 +- 0.00002 d (= 76.78 m) for GW Lib and and 0.054643 +- 0.000007 d (= 78.69 m) for V844 Her. Recently, the orbital period of DI UMa was found to be only 0.054564 +- 0.000002 d (= 78.57 m) by Fried et al. (1999), so these are the three shortest orbital periods among dwarf novae with normal-abundance secondaries. GW Lib has attracted attention as a cataclysmic binary showing apparent ZZ Ceti-type pulsations of the white dwarf primary. Its spectrum shows sharp Balmer emission flanked by strong, broad Balmer absorption, indicating a dominant contribution by white-dwarf light. Analysis of the Balmer absorption profiles is complicated by the unknown residual accretion luminosity and lack of coverage of the high Balmer lines. Our best-fit model atmospheres are marginally hotter than the ZZ Ceti instability strip, in rough agreement with recent ultraviolet results from HST. The spectrum and outburst behavior of GW Lib make it a near twin of WZ Sge, and we estimate it to have a quiescent V absolute magnitude 12. Comparison with archival data reveals proper motion of 65 +- 12 mas/yr. The mean spectrum of V844 Her is typical of SU UMa dwarf novae. We detected superhumps in the 1997 May superoutburst with superhump period = 0.05597 +- 0.00005 d. The spectrum of DI UMa appears normal for a dwarf nova near minimum light. These three dwarf novae have nearly identical short periods but completely dissimilar outburst characteristics. We discuss possible implications.Comment: Accepted for publication in Publications of the Astronomical Society of the Pacific; 16 pages, 6 figure

SMS texts on corruption help Ugandan voters hold elected councillors accountable at the polls

Many politicians manipulate information to prevent voters from holding them accountable; however, mobile text messages may make it easier for nongovernmental organizations to credibly share information on official corruption that is difficult for politicians to counter directly. We test the potential for texts on budget management to improve democratic accountability by conducting a large (n = 16,083) randomized controlled trial during the 2016 Ugandan district elections. In cooperation with a local partner, we compiled, simplified, and text-messaged official information on irregularities in local government budgets. Verified recipients of messages that described more irregularities than expected reported voting for incumbent councillors 6% less often; verified recipients of messages conveying fewer irregularities than expected reported voting for incumbent councillors 5% more often. The messages had no observable effect on votes for incumbent council chairs, potentially due to voters\u27 greater reliance on other sources of information for higher profile elections. These mixed results suggest that text messages on budget corruption help voters hold some politicians accountable in settings where elections are not free and fair

Information about service provision in Uganda is insufficient to affect voting behaviour

The quality of service provision in Uganda varies greatly across regions and between villages, and yet evidence suggests citizens’ are unable to assess these differences. A research experiment used SMS messages about public services to help Ugandans make informed voting decisions, but it found no effect on voting outcomes. Here is why information alone is sometimes insufficient to affect political behaviour

Individualized text messages about public services fail to sway voters: evidence from a field experiment on Ugandan elections

Mobile communication technologies can provide citizens access to information that is tailored to their specific circumstances. Such technologies may therefore increase citizens' ability to vote in line with their interests and hold politicians accountable. In a large-scale randomized controlled trial in Uganda (n = 16,083), we investigated whether citizens who receive private, timely, and individualized text messages by mobile phone about public services in their community punished or rewarded incumbents in local elections in line with the information. Respondents claimed to find the messages valuable and there is evidence that they briefly updated their beliefs based on the messages; however, the treatment did not cause increased votes for incumbents where public services were better than expected nor decreased votes where public services were worse than anticipated. The considerable knowledge gaps among citizens identified in this study indicate potential for communication technologies to effectively share civic information. Yet the findings imply that when the attribution of public service outcomes is difficult, even individualized information is unlikely to affect voting behavior

The Optical System for the Large Size Telescope of the Cherenkov Telescope Array

The Large Size Telescope (LST) of the Cherenkov Telescope Array (CTA) is designed to achieve a threshold energy of 20 GeV. The LST optics is composed of one parabolic primary mirror 23 m in diameter and 28 m focal length. The reflector dish is segmented in 198 hexagonal, 1.51 m flat to flat mirrors. The total effective reflective area, taking into account the shadow of the mechanical structure, is about 368 m$^2$. The mirrors have a sandwich structure consisting of a glass sheet of 2.7 mm thickness, aluminum honeycomb of 60 mm thickness, and another glass sheet on the rear, and have a total weight about 47 kg. The mirror surface is produced using a sputtering deposition technique to apply a 5-layer coating, and the mirrors reach a reflectivity of $\sim$94% at peak. The mirror facets are actively aligned during operations by an active mirror control system, using actuators, CMOS cameras and a reference laser. Each mirror facet carries a CMOS camera, which measures the position of the light spot of the optical axis reference laser on the target of the telescope camera. The two actuators and the universal joint of each mirror facet are respectively fixed to three neighboring joints of the dish space frame, via specially designed interface plate.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589