scholarly journals Hearing restoration by a low-weight power-efficient multichannel optogenetic cochlear implant system

Author(s):  
Lukasz Jablonski ◽  
Tamas Harczos ◽  
Bettina Wolf ◽  
Gerhard Hoch ◽  
Alexander Dieter ◽  
...  

In case of deafness, cochlear implants bypass dysfunctional or lost hair cells by direct electrical stimulation (eCIs) of the auditory nerve. However, spectral selectivity of eCI sound coding is low as the wide current spread from each electrode activates large sets of neurons that align to a place-frequency (tonotopic) map in the cochlea. As light can be better confined in space, optical cochlear implants (oCIs) promise to overcome this shortcoming of eCIs. This requires fine-grained, fast, and power-efficient real-time sound analysis and control of multiple microscale emitters. Here, we describe the development, characterisation, and application for hearing restoration of a preclinical low-weight and wireless LED-based multichannel oCI system and its companion eCI system. The head-worn oCI system enabled deafened rats to perform a locomotion task in response to acoustic stimulation proving the concept of multichannel optogenetic hearing restoration in rodents.

2008 ◽  
Vol 242 (1-2) ◽  
pp. 22-30 ◽  
Author(s):  
Kensall D. Wise ◽  
Pamela T. Bhatti ◽  
Jianbai Wang ◽  
Craig R. Friedrich

2020 ◽  
Author(s):  
Muhammad Roomi ◽  
Yaser Khan

<p>The ongoing search to contain and control the spread of COVID-19 disease focuses on discovering drugs or vaccines that can play an essential role in treating this contagious disease. This paper focuses on natural compounds that can play a vital role in the treatment of Covid-19. The study spans over the chemicals that have the potential to bind with the key residues of type II Transmembrane Protease Serine (TMPRSS2). TMPRSS2 can be termed as the catalyst that cleaves the spike glycoproteins of Sars-Cov-2, which causes the replication and spread of virus inside the human body by facilitating virus-cell fusions. Drugs like Camostat Mesylate, Aprotinin, and Rimantadine have been proposed as potential inhibitors of TMPRSS2. After screening large sets of phytochemicals and flavonoids extracted from plants, potential compounds have been tested, and a set of most effective and suitable compounds are chosen for further studies. These selected compounds are further analyzed in terms of binding with key residues as well as high binding affinity with TMPRSS2. The in silico analysis of possible chemical compounds is carried out by using docking, screening analysis, Molecular Dynamics, and Electrostatic Potential Simulations. Chemicals extracted from different plants are comparatively analyzed with drugs like Aprotinin, Camostat Mesylate, and Rimantadine.</p>


Author(s):  
E. J. de Waard

Decentralized, peer-to-peer command and control is a key principle of network-centric operations that has received a lot of scholarly attention. So far, robust networking, another principle, has remained rather underexposed in the academic debate. This chapter introduces theory on modular organizing to start a discourse on network robustness from an organizational design perspective. Above all, the chapter makes clear that the level of system decomposition influences the command and control process of composite military structures. When military organizations follow a fine-grained modularization approach, the structure of a task force deployed may become complex, asking for extra coordination mechanisms to achieve syntheses between the many contributing functional organizational components. In addition, it is argued that modularity's principle of near-decomposability has to be incorporated into the available mathematical models on network-centric operations. A point of concern, in this respect, is that the current modeling parameters make no clear distinction between the different types of actors—or nodes—in a military network structure, whereas in reality, technological, organizational, and human actors all live by their own specific rules.


Author(s):  
Qiang Guan ◽  
Nathan DeBardeleben ◽  
Sean Blanchard ◽  
Song Fu ◽  
Claude H. Davis IV ◽  
...  

As the high performance computing (HPC) community continues to push towards exascale computing, HPC applications of today are only affected by soft errors to a small degree but we expect that this will become a more serious issue as HPC systems grow. We propose F-SEFI, a Fine-grained Soft Error Fault Injector, as a tool for profiling software robustness against soft errors. We utilize soft error injection to mimic the impact of errors on logic circuit behavior. Leveraging the open source virtual machine hypervisor QEMU, F-SEFI enables users to modify emulated machine instructions to introduce soft errors. F-SEFI can control what application, which sub-function, when and how to inject soft errors with different granularities, without interference to other applications that share the same environment. We demonstrate use cases of F-SEFI on several benchmark applications with different characteristics to show how data corruption can propagate to incorrect results. The findings from the fault injection campaign can be used for designing robust software and power-efficient hardware.


2020 ◽  
Vol 47 (11) ◽  
pp. 947-964 ◽  
Author(s):  
Carina L. Gargalo ◽  
Isuru Udugama ◽  
Katrin Pontius ◽  
Pau C. Lopez ◽  
Rasmus F. Nielsen ◽  
...  

AbstractThe biomanufacturing industry has now the opportunity to upgrade its production processes to be in harmony with the latest industrial revolution. Technology creates capabilities that enable smart manufacturing while still complying with unfolding regulations. However, many biomanufacturing companies, especially in the biopharma sector, still have a long way to go to fully benefit from smart manufacturing as they first need to transition their current operations to an information-driven future. One of the most significant obstacles towards the implementation of smart biomanufacturing is the collection of large sets of relevant data. Therefore, in this work, we both summarize the advances that have been made to date with regards to the monitoring and control of bioprocesses, and highlight some of the key technologies that have the potential to contribute to gathering big data. Empowering the current biomanufacturing industry to transition to Industry 4.0 operations allows for improved productivity through information-driven automation, not only by developing infrastructure, but also by introducing more advanced monitoring and control strategies.


Author(s):  
Gillian Robyn Kerr ◽  
Seppo Tuomi ◽  
Alida Müller

Cochlear implantation is an expensive but effective lifelong intervention for individuals with a severe-to-profound hearing loss. The primary aim of this study was to survey the short- and long-term costs of cochlear implantation. Individuals (N=154) using cochlear implants obtained from the University of Stellenbosch-Tygerberg Hospital Cochlear Implant Unit in Cape Town, South Africa were surveyed using a questionnaire and patient record review. The questionnaire used a combination of closed and open-ended questions to gather both quantitative and qualitative information. Costs were categorised as short- and long-term costs. All costs were converted to constant rands (June 2010) using the Consumer Price Index to allow for comparison in real terms over time. In the first 10 years of implantation the average estimated costs incurred by adults totalled R379 626, and by children R455 225. The initial purchase of the implant system was the most substantial cost, followed by upgrading of the processor. Travel and accommodation costs peaked in the first 2 years. On average the participants spent R2 550 per year on batteries and spares. Rehabilitation for children cost an average of R7 200. Insurance costs averaged R4 040 per year, and processor repairs R3 000 each. In addition to the upfront expense of obtaining the cochlear implant system, individuals using a cochlear implant in South Africa should be prepared for the long-term costs of maintenance, accessing the unit, support services and additional costs associated with use. Knowledge of these costs is important to ensure that individuals are successful users of their cochlear implants in the long term.


2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
S. Irving ◽  
L. Gillespie ◽  
R. Richardson ◽  
D. Rowe ◽  
J. B. Fallon ◽  
...  

Cochlear implants have provided hearing to hundreds of thousands of profoundly deaf people around the world. Recently, the eligibility criteria for cochlear implantation have been relaxed to include individuals who have some useful residual hearing. These recipients receive inputs from both electric and acoustic stimulation (EAS). Implant recipients who can combine these hearing modalities demonstrate pronounced benefit in speech perception, listening in background noise, and music appreciation over implant recipients that rely on electrical stimulation alone. The mechanisms bestowing this benefit are unknown, but it is likely that interaction of the electric and acoustic signals in the auditory pathway plays a role. Protection of residual hearing both during and following cochlear implantation is critical for EAS. A number of surgical refinements have been implemented to protect residual hearing, and the development of hearing-protective drug and gene therapies is promising for EAS recipients. This review outlines the current field of EAS, with a focus on interactions that are observed between these modalities in animal models. It also outlines current trends in EAS surgery and gives an overview of the drug and gene therapies that are clinically translatable and may one day provide protection of residual hearing for cochlear implant recipients.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Sheryl L. Chang ◽  
Nathan Harding ◽  
Cameron Zachreson ◽  
Oliver M. Cliff ◽  
Mikhail Prokopenko

Abstract There is a continuing debate on relative benefits of various mitigation and suppression strategies aimed to control the spread of COVID-19. Here we report the results of agent-based modelling using a fine-grained computational simulation of the ongoing COVID-19 pandemic in Australia. This model is calibrated to match key characteristics of COVID-19 transmission. An important calibration outcome is the age-dependent fraction of symptomatic cases, with this fraction for children found to be one-fifth of such fraction for adults. We apply the model to compare several intervention strategies, including restrictions on international air travel, case isolation, home quarantine, social distancing with varying levels of compliance, and school closures. School closures are not found to bring decisive benefits unless coupled with high level of social distancing compliance. We report several trade-offs, and an important transition across the levels of social distancing compliance, in the range between 70% and 80% levels, with compliance at the 90% level found to control the disease within 13–14 weeks, when coupled with effective case isolation and international travel restrictions.


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