In vivo auditory nerve stimulation with visible light

Background: Infrared laser stimulation has been proposed as an innovative method to elicit an auditory nerve response. Most studies have focused on using long-wavelength infrared (>980nm) pulsed lasers with high water absorption coefficients. This paper sought to assess whether a short-wavelength laser (465nm) with an absorption coefficient as low as 10−3cm−1 would activate the auditory nerve and studied its potential mechanism. Method: Optical compound action potentials (OCAPs) were recorded when synchronous trigger laser pulses stimulate the cochlea before and after deafening, varying the pulse durations (from 800μs to 3600μs) and the amount of radiant energy (from 18.05mJ/cm2 to 107.91mJ/cm2). A thermal infrared imager was applied to monitor the temperature change of the guinea pig cochlea. Results: The results showed that pulsed laser stimulation at 465nm could invoke OCAPs and had a similar waveform compared to the acoustical compound action potentials. The amplitude of OCAPs had a positive correlation with the increasing laser peak power, while the latency of OCAPs showed a negative correlation. The imager data showed that the temperature in the cochlea rose quickly by about 0.3∘C right after stimulating the cochlea and decreased quickly back to the initial temperature as the stimulation ended. Conclusions: This paper demonstrates that 465-nm laser stimulation can successfully induce OCAPs outside the cochlea, and that the amplitude and latency of the invoked OCAPs are highly affected by laser peak power. This paper proposes that a photothermal effect might be the main mechanism for the auditory nerve response induced by short-wavelength laser stimulation

Task 28: Web Accessible APIs in the Cloud Trade Study

This study explored three candidate architectures for serving NASA Earth Science Hierarchical Data Format Version 5 (HDF5) data via Hyrax running on Amazon Web Services (AWS). We studied the cost and performance for each architecture using several representative Use-Cases. The objectives of the project are: Conduct a trade study to identify one or more high performance integrated solutions for storing and retrieving NASA HDF5 and Network Common Data Format Version 4 (netCDF4) data in a cloud (web object store) environment. The target environment is Amazon Web Services (AWS) Simple Storage Service (S3).Conduct needed level of software development to properly evaluate solutions in the trade study and to obtain required benchmarking metrics for input into government decision of potential follow-on prototyping. Develop a cloud cost model for the preferred data storage solution (or solutions) that accounts for different granulation and aggregation schemes as well as cost and performance trades

Basic Terra fusion product algorithm theoretical basis and data specifications

The basic Terra fusion product provides general atmospheric and surface research community a unique temporally-fused set of radiance measurements from all the Terra instruments, namely, the Moderate-resolution Imaging Spectroradiometer (MODIS), the Multi-angle Imaging SpectroRadiometer (MISR), the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), the Clouds and Earth’s Radiant Energy System (CERES), and the Measurements of Pollution in the Troposphere (MOPITT). This product contains (1) radiance values of IOFVs (pixels) for each spectral band at a native resolution for each instrument, (2) their quality flags associated with radiance values, (3) their latitude and longitude information at a native resolution, (4) time of observations, (5) instrument viewing geometry, and (6) solar position.NASA ACCESS program under contract NNX16AMO7AThis research is part of the Blue Waters sustained-petascale computing project, which is supported by the National Science Foundation (awards OCI-0725070 and ACI-1238993) and the state of Illinois. Blue Waters is a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications.The computations for this research also used the NSF-supported ROGER (Resourcing Open Geospatial Education and Research) cyberGIS supercomputer (Award#: 1429699).Ope

Origin, Maintenance and Fine-Scale Structure of 14-15 February 1992 Mesoscale Gravity Wave Observed During Storm-Fest

160 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1999.The gravity wave was generated behind the leading edge of an advancing dry surge moving over a warm frontal inversion. The dry surge, which had the characteristics of density current, originated as a foehn-like downslope flow over the Rocky Mountains of southern Colorado and New Mexico. The advancing dry surge provided a continuous energy source for both the mesoscale gravity wave and convection. Internal circulations within the dry surge created the mesoscale gravity wave while lifting of air ahead of the dry surge created a line of convection. There was no direct relationship between the convection and the mesoscale gravity wave in the sense that neither forced the other. Both were generated and maintained by the advancing dry surge. Deceleration within the dry surge led to a branched circulation within the flow, with the descending branch depressing the height of the warm frontal inversion creating the wave, and the ascending branch creating the dry surge head. Pressure and virtual potential temperature perturbations were generated by the advancing dry surge and associated convection. Strong horizontal perturbation pressure gradients were associated with both the abrupt deceleration of air near the leading edge of the dry surge and with the divergent flow at the top of the convective updraft. The virtual potential temperature perturbation was associated with the vertical gradient of pressure perturbation because the convection was weak. In the second phase, in central-eastern Missouri, the wave disturbance decoupled from, and moved ahead of the dry surge. Surface pressure and wind measurements suggest that the disturbance was a bore. The bore propagated into a region where wave-ducting was effective, allowing it to maintain its structure over a long distance.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Origin, Maintenance and Fine-Scale Structure of 14-15 February 1992 Mesoscale Gravity Wave Observed During Storm-Fest

160 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1999.The gravity wave was generated behind the leading edge of an advancing dry surge moving over a warm frontal inversion. The dry surge, which had the characteristics of density current, originated as a foehn-like downslope flow over the Rocky Mountains of southern Colorado and New Mexico. The advancing dry surge provided a continuous energy source for both the mesoscale gravity wave and convection. Internal circulations within the dry surge created the mesoscale gravity wave while lifting of air ahead of the dry surge created a line of convection. There was no direct relationship between the convection and the mesoscale gravity wave in the sense that neither forced the other. Both were generated and maintained by the advancing dry surge. Deceleration within the dry surge led to a branched circulation within the flow, with the descending branch depressing the height of the warm frontal inversion creating the wave, and the ascending branch creating the dry surge head. Pressure and virtual potential temperature perturbations were generated by the advancing dry surge and associated convection. Strong horizontal perturbation pressure gradients were associated with both the abrupt deceleration of air near the leading edge of the dry surge and with the divergent flow at the top of the convective updraft. The virtual potential temperature perturbation was associated with the vertical gradient of pressure perturbation because the convection was weak. In the second phase, in central-eastern Missouri, the wave disturbance decoupled from, and moved ahead of the dry surge. Surface pressure and wind measurements suggest that the disturbance was a bore. The bore propagated into a region where wave-ducting was effective, allowing it to maintain its structure over a long distance.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Photoacoustic effect invokes auditory response in infrared neuron stimulation

Infrared neuron stimulation is regarded as an innovative approach for stimulating cochleae in animals while the exact mechanism still remains unknown. In this paper, we studied compound action potentials of guinea pig cochleae with chronic or acute deafness. We recorded optical compound action potentials and analyzed stretched cochlear preparations by fluorescence microscopy. Photoacoustic signals were measured by hydrophone and microphone, respectively. In our experiment, we observed a switch response effect in vitro and in vivo experiments. Therefore, we proposed photoacoustic effect could invoke auditory response in infrared neuron stimulation

A photoacoustic imaging system with variable gain at different depths

We established a photoacoustic imaging (PAI) system that can provide variable gain at different depths. The PAI system consists of a pulsed laser with an optical parametric oscillator working at a 728nm wavelength and an imaging-acquisition-and-processing unit with an ultrasound transducer. A voltage-controlled attenuator was used to realize variable gain at different depths when acquiring PAI signals. The proof-of-concept imaging results for variable gain at different depths were achieved using specific phantoms. Both resolution and optical contrast obtained through the results of variable gain for a targeted depth range are better than those of constant gain for all depths. To further testify the function, we imaged the sagittal section of the body of in vivo nude mice. In addition, we imaged an absorption sample embedded in a chicken breast tissue, reaching a maximum imaging depth of ∼4.6cm. The results obtained using the proposed method showed better resolution and contrast than when using 50dB gain for all depths. The depth range resolution was ∼1mm, and the maximum imaging depth of our system reached ∼4.6cm. Furthermore, blood vessels can be revealed and targeted depth range can be selected in nude mice imaging

Probiotic as Adjuvant Significantly Improves Protection of the Lanzhou Trivalent Rotavirus Vaccine against Heterologous Challenge in a Gnotobiotic Pig Model of Human Rotavirus Infection and Disease

This preclinical study in the gnotobiotic (Gn) pig model of human rotavirus (HRV) infection and disease evaluates the effect of probiotic Lactobacillus rhamnosus GG (LGG) as a mucosal adjuvant on the immunogenicity and cross-protective efficacy of the Lanzhou live oral trivalent (G2, G3, G4) vaccine (TLV, aka LLR3). Gn pigs were immunized with three doses of TLV with or without concurrent administration of nine doses of LGG around the time of the first dose of the TLV vaccination, and were challenged orally with the virulent heterotypic Wa G1P[8] HRV. Three doses of TLV were highly immunogenic and conferred partial protection against the heterotypic HRV infection. LGG significantly enhanced the intestinal and systemic immune responses and improved the effectiveness of protection against the heterotypic HRV challenge-induced diarrhea and virus shedding. In conclusion, we demonstrated the immune-stimulating effects of probiotic LGG as a vaccine adjuvant and generated detailed knowledge regarding the cross-reactive and type-specific antibody and effector B and T cell immune responses induced by the TLV. Due to the low cost, ease of distribution and administration, and favorable safety profiles, LGG as an adjuvant has the potential to play a critical role in improving rotavirus vaccine efficacy and making the vaccines more cost-effective