Portable Laboratory Research Articles

Evaluation of a research hearing aid for audiological testing

Objective Open-source hearing aid (HA) research tools provide avenues for testing new audiological concepts. This study compared a wearable research HA (RHA) – the “Portable Hearing Laboratory” – to a high-end commercial HA (CHA) in terms of aided outcome. Using this RHA, it also evaluated a fitting approach based on non-individualised gain presets. Design Using a randomised repeated-measures design, participants completed speech recognition and speech quality assessments under unaided and several aided (RHA and CHA with omnidirectional and directional microphone settings) conditions. Furthermore, two approaches for prescribing amplification were evaluated with the RHA: (1) a preset approach based on non-verified clinical gain targets calculated for three standard audiograms, and (2) a best-practice approach based on individually prescribed and verified clinical gain targets. Study sample Fifteen adults aged 50–78 years with symmetrical, mild-to-moderate sensorineural hearing losses. Results The RHA and CHA gave similar audibility, speech recognition in quiet and in noise, and speech quality ratings in quiet and in noise. Relative to the best-practice approach, the preset approach resulted in less audibility but similar speech recognition in quiet and in noise. Conclusion The RHA appears suited for testing new audiological concepts such as preset-based approaches to HA fitting.

Effective Surveillance of Water Quality in Recirculating Aquaculture Systems through the Application of Intelligent Biosensors

Water quality (WQ) is the paramount element influencing fish well-being and productivity in aquaculture farming systems. The survival of fish is mostly reliant on the aquatic environment that sustains them. Consequently, it is vital to possess a comprehensive awareness of the WQ prerequisites for the fish. Optimal WQ in Recirculating Aquaculture Systems (RAS) is essential for cultivating species' effective development and survival. Currently, no laws dictate the parameters to be monitored in RAS, leaving each farmer to choose which parameters to monitor. Historically, WQ measurements have been assessed at certain intervals using portable sensors and laboratory tests, which may be labor-intensive. This study proposes an Effective Surveillance of Water Quality (ESWQ) in RAS using Intelligent Biosensors (IBS). This study examines essential water characteristics (temperature, pH, calcium, magnesium, and Dissolved Oxygen (DO)) for RAS and evaluates the IBS for monitoring these factors. This research provides a potential solution for RAS using IBS, which would enhance ESWQ aspects, facilitate data-driven decision-making, and enable more rapid adaptation to evolving RAS situations.

Utilizing Insects as Bioindicators: An Approximation for Conservation in Urban Lentic Ecosystems in Central Chile.

This study considered using insect families as bioindicators to establish the health status of an ecosystem of lentic bodies. The water quality in urban lentic bodies in the Metropolitan Region, Chile, was evaluated from aquatic insect family assemblages and physicochemical variables for conserving aquatic life. Evaluations were carried out in parallel at four sampling stations of three water bodies (Batuco Wetland, Carén Lagoon, and Chada Reservoir) in a 2-3-year series, spring (2015, 2017, and 2018) and fall (2016 and 2018), with three replicates. Families were randomly sampled and aquatic insects were identified; abundance and richness differences were compared with non-parametric tests. Physicochemical variables were measured using portable multiparametric and laboratory chemical analyses to determine the water quality. A Canonical Correspondence Analysis was applied for insect families and the physical-chemical variable. In order to categorize the health of these water bodies based on aquatic insect composition and abundance, the Family Biotic Index (FBI), British Biological Monitoring Work Party (BMWP), and Stream Invertebrate Grade Number-Average Level (SIGNAL), adapted for Chile by Figueroa et al. (2007), were calculated. The eudominant insect families were Corixidae and Chironomidae in Batuco, Chironomidae and Corixidae in Carén, and Corixidae in Chada. Baetidae was dominant in Carén and Chada. The water bodies were classified in descending order of water quality by Chilean physicochemical standards: Chada > Carén > Batuco. The TSS (total suspended solids), phosphorus, and electrical conductivity were strongly positively correlated and negatively associated with dissolved oxygen. The TSS level was the most significant influential factor. The BMWP value and the SIGNAL differed from the FBI, but the first was more restrictive, contributing to the conservation of these ecosystems. Based on the nitrogen and phosphorus levels in the water bodies, all of them were eutrophic. Given the ecosystem diversity and complexity, studies should delve deeper into wetlands to establish methods that contribute to determining water quality, using insect families as bioindicators and physicochemical variables.

Comparative Investigation of Mobile Portable Complex System Functional and Laboratory Diagnostics with Stationary Equipment

The aim of the current study is to evaluate the effectiveness of using mobile portable complex system functional and laboratory diagnostics in patients compared to stationary equipment. The scientific study examined the results of functional and laboratory diagnostics of 123 patients who were at JSC NSMC at the time of diagnosis and treatment. The study covered a 1-year period from January 2023 to December 2023. Patients were divided into two groups: 1 group  - 63 patients, who were diagnosed using expert stationary equipment of NNMC; 2 group- 60 patients who were diagnosed using the mobile portable complex Health Examination System HES-7 (Konsung Technology; 2023). Results: Laboratory diagnostics were performed in 63 (100%) patients of the 1<sup>st</sup> group and in 60 (100%) patients of 2<sup>nd</sup> group. The compared groups had the same characteristics, for instance anaemia was detected in 4 (6.35%) patients of first group and in 5 (8.33%) patients of the second group. Mortality was not observed in the compared groups. According to all data obtained minor differences in diagnostic findings were found (1 to 6%). In addition, HES-7 demonstrated quite accurate functional analysis: electrocardiography, pulse oximetry, and spirography. Conclusion: The use of the digital mobile complex of functional and laboratory diagnostics Health Examination System HES-7 is safe and can be effectively used in primary health care settings by experienced nursing staff.

Dual-Mode Fluorescent/Intelligent Lateral Flow Immunoassay Based on Machine Learning Algorithm for Ultrasensitive Analysis of Chloroacetamide Herbicides.

Given the harmful effect of pesticide residues, it is essential to develop portable and accurate biosensors for the analysis of pesticides in agricultural products. In this paper, we demonstrated a dual-mode fluorescent/intelligent (DM-f/DM-i) lateral flow immunoassay (LFIA) for chloroacetamide herbicides, which utilized horseradish peroxidase-IgG conjugated time-resolved fluorescent nanoparticle probes as both a signal label and amplification tool. With the newly developed LFIA in the DM-f mode, the limits of detection (LODs) were 0.08 ng/mL of acetochlor, 0.29 ng/mL of metolachlor, 0.51 ng/mL of Propisochlor, and 0.13 ng/mL of their mixture. In the DM-i mode, machine learning (ML) algorithms were used for image segmentation, feature extraction, and correlation analysis to obtain multivariate fitted equations, which had high reliability in the regression model with R2 of 0.95 in the range of 2 × 102-2 × 105 pg/mL. Importantly, the practical applicability was successfully validated by determining chloroacetamide herbicides in the corn sample with good recovery rates (85.4 to 109.3%) that correlate well with the regression model. The newly developed dual-mode LFIA with reduced detection time (12 min) holds great potential for pesticide monitoring in equipment-limited environments using a portable test strip reader and laboratory conditions using ML algorithms.

Control-Lab-in-a-Box: Bridging the Gap between Control Theory and Engineering Practice

Traditional control engineering teaching methods heavily rely on abstract mathematical concepts, often leaving students puzzled about real-world applications. Common simulation tools, such as MATLAB and Simulink provide a good visual demonstration but don't necessarily bridge the gap between theory and application. The proposed ‘lab-in-a-box’ approach offers a tangible method for students to connect control theory with a practical control engineering experience. The literature has observed a shift towards such portable labs, given the advancements in compact computing devices such as Raspberry Pi and Arduino boards in electronics and control teaching. The primary goal of these labs is to deliver an authentic engineering experience with essential hardware. Evaluation of this method, through the student module evaluation questionnaire (MEQ), revealed a significant increase in student satisfaction after its introduction. While the results are promising, challenges remain, such as the initial set-up of the kits. However, the ‘lab-in-a-box’ is found to be a valuable tool in control engineering education, bridging the gap between theoretical and practical understanding. An on-going development includes updating of the kits to match future engineering challenges and needs, e.g., electrification and autonomy of vehicles.

Effect of pedestrian trampling on aeolian sand dynamics on beach surfaces: An experimental study

Wind tunnel experiments and measurements with the Portable In-Situ Wind Erosion Laboratory (PI-SWERL) were conducted to investigate the effect footprints on a sandy beach have on aerodynamic roughness, physical roughness, and the wind erosion threshold. Footprints parallel and footprints perpendicular to the wind were tested, for bare feet and walking shoes, for a lighter (63 kg) and a heavier (75 kg) person. The data were compared to a flat undisturbed surface, which served as control. Results show that footprints have a significant effect on aerodynamic roughness and on the wind erosion threshold. Aerodynamic roughness is higher, and the wind erosion threshold lower, for footprints parallel to the wind compared to footprints perpendicular to the wind, for footprints produced with bare feet compared to footprints produced by walking shoes, and for footprints made by a heavier person compared to footprints made by a lighter person. The differences with an undisturbed flat surface, for which aerodynamic roughness is small and the wind erosion threshold high, were found to be substantial. Of the measured physical roughness parameters of the footprints, surface area of the imprint showed the highest correlation with aerodynamic roughness. The effect of the volume and the average depth of the imprint on aerodynamic roughness was much smaller or even not statistically significant. The PI-SWERL measurements also suggested that on dry sandy surfaces foot imprints may rapidly disintegrate, even when the wind is only slightly above the erosion threshold. This study shows that when wind erosion models are used to describe and predict the initial phase of wind erosion on sandy beaches, the process of trampling with footprints should at least be considered.

On-Demand, Contact-Less and Loss-Less Droplet Manipulation via Contact Electrification.

While there are many droplet manipulation techniques, all of them suffer from at least one of the following drawbacks - complex fabrication or complex equipment or liquid loss. In this work, a simple and portable technique is demonstrated that enables on-demand, contact-less and loss-less manipulation of liquid droplets through a combination of contact electrification and slipperiness. In conjunction with numerical simulations, a quantitative analysis is presented to explain the onset of droplet motion. Utilizing the contact electrification technique, contact-less and loss-less manipulation of polar and non-polar liquid droplets on different surface chemistries and geometries is demonstrated. It is envisioned that the technique can pave the way to simple, inexpensive, and portable lab on a chip and point of care devices.

Air monitoring by nanopore sequencing.

While the air microbiome and its diversity are essential for human health and ecosystem resilience, comprehensive air microbial diversity monitoring has remained rare, so that little is known about the air microbiome's composition, distribution, or functionality. Here we show that nanopore sequencing-based metagenomics can robustly assess the air microbiome in combination with active air sampling through liquid impingement and tailored computational analysis. We provide fast and portable laboratory and computational approaches for air microbiome profiling, which we leverage to robustly assess the taxonomic composition of the core air microbiome of a controlled greenhouse environment and of a natural outdoor environment. We show that long-read sequencing can resolve species-level annotations and specific ecosystem functions through de novo metagenomic assemblies despite the low amount of fragmented DNA used as an input for nanopore sequencing. We then apply our pipeline to assess the diversity and variability of an urban air microbiome, using Barcelona, Spain, as an example; this randomized experiment gives first insights into the presence of highly stable location-specific air microbiomes within the city's boundaries, and showcases the robust microbial assessments that can be achieved through automatable, fast, and portable nanopore sequencing technology.

Benefit of Hearing-Aid Amplification and Signal Enhancement for Speech Reception in Complex Listening Situations.

A major goal of hearing-device provision is to improve communication in daily life. However, there is still a large gap between the user's daily-life aided listening experience and hearing-aid benefit as assessed with established speech reception measurements in the laboratory and clinical practice. For a more realistic assessment, hearing-aid provision needs to be tested in suitable acoustic environments. In this study, using virtual acoustics, we developed complex acoustic scenarios to measure speech-intelligibility and listening-effort benefit obtained from hearing-aid amplification and signal enhancement strategies. Measurements were conducted using the participants' own devices and a research hearing aid, the Portable Hearing Laboratory (PHL). On the PHL, in addition to amplification, a monaural and a binaural directional filter, as well as a spectral filter were employed. We assessed the benefit from different signal enhancement strategies at the group and the individual level. At the group level, signal enhancement including directional filtering provided a higher hearing-aid benefit in challenging acoustic scenarios in terms of speech intelligibility compared to amplification alone or combined with spectral filtering. However, no difference between monaural and binaural signal enhancement occurred. On an individual level, we found large differences in hearing-aid benefit between participants. While some benefitted from signal-enhancement algorithms, others benefitted from amplification alone, but additional signal enhancement had a detrimental effect. This shows the importance of an individual selection of signal enhancement strategies as a part of the hearing-aid fitting process.

ElectrochemCap: an integrated detection for loop-mediated isothermal amplification reactions.

Loop-mediated isothermal amplification (LAMP) of genetic materials has emerged as a powerful molecular biology technique with great potential to be a standard point-of-care (POC) technique. This method has found several applications, but it still presents challenges for its direct on-site application, particularly in terms of integrated reaction and detection systems and the risk of carryover contamination. In this work, we propose an innovative solution - an electrochemical microcentrifuge tube cap (ElectrochemCap) based on a screen-printed electrode, a 3D printed adapter and an adhesive layer - which integrates the amplification reaction and its subsequent electrochemical detection in a single device. The design, fabrication, and electrochemical characterization of the ElectrochemCap are reported here, demonstrating its suitability for LAMP detection. Rapidly emerging technologies, such as 3D printing or xurography, are the basis of a prototype that has been validated for the detection of SARS-CoV-2 using reverse transcription LAMP (RT-LAMP), achieving results comparable to those obtained by gold-standard RT-qPCR. Moreover, we have explored the versatility of the ElectrochemCap presenting several additional designs (for containers with different volumes, shapes and materials, as well as multiplexed approaches), expanding its potential applications. Overall, the ElectrochemCap represents an affordable, versatile, and marketable innovation for integrated quantitative electrochemical detection, with enormous possibilities in bioelectroanalytical procedures and portable laboratory setups.

In situ metagenomics: A platform for rapid sequencing and analysis of metagenomes in less than one day.

We present here a complete system for metagenomic analysis that allows performing the sequencing and analysis of a medium-size metagenome in less than one day. This unprecedented development was possible due to the conjunction of state-of-the-art experimental and computational advances: a portable laboratory suitable for DNA extraction and sequencing with nanopore technology; the powerful metagenomic analysis pipeline SqueezeMeta, capable to provide a complete analysis in a few hours and using scarce computational resources; and tools for the automatic inspection of the results via a graphical user interface, that can be coupled to a web server to allow remote visualization of data (SQMtools and SQMxplore). We have tested the feasibility of our approach in the sequencing of the microbiota associated to volcanic rocks in La Palma, Canary Islands. Also, we did a two-day sampling campaign of marine waters in which the results obtained on the first day guided the experimental design of the second day. We demonstrate that it is possible to generate metagenomic information in less than one day, making it feasible to obtain taxonomic and functional profiles fast and efficiently, even in field conditions. This capacity can be used in the further to perform real-time functional and taxonomic monitoring of microbial communities in remote areas.

Rapid and sensitive on-site detection of SARS-CoV-2 RNA from environmental surfaces using portable laboratory devices.

Monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA on inanimate surfaces plays a crucial role in environmental surveillance, enabling the indirect detection of infected individuals and facilitating rapid infection control responses. However, developing a practical on-site, end-to-end method for detection remains a challenge. In this study, we established protocols for on-site detection of SARS-CoV-2 RNA on surfaces using two portable laboratory devices: The PicoGene PCR1100 and Bento Lab. Test particles comprised of inactivated viral particles containing partial sequences of SARS-CoV-2, type 1 poliovirus, coxsackie virus A16, and norovirus genogroups I and II were applied to reference materials as simulated contaminants. The direct detection method with the PicoGene PCR1100 achieved a recovery efficiency of 35.1% for the dried reference material. Furthermore, the Bento Lab, equipped with a microcentrifuge for on-site RNA purification, successfully detected a low concentration of inactivated SARS-CoV-2 reference standard. The recovery efficiency of the on-site RNA purification method on plastic, stainless steel, glass, and polyvinyl chloride surfaces ranged from 15.5% to 21.2%. Through the combination of these portable devices, SARS-CoV-2 RNA was detected within 1 h of swab sampling. This study contributes to the on-site risk assessment of infectious diseases by enabling the rapid detection of viral genomes. IMPORTANCE This study presents the development of a highly sensitive on-site method for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA on various surfaces, including doorknobs and tables. Identifying SARS-CoV-2 RNA on these surfaces can be crucial in guiding decision-making for implementing non-pharmaceutical interventions, such as zoning strategies, improving ventilation, maintaining physical distancing, and promoting increased hand hygiene practices. Moreover, the on-site detection system can facilitate the swift initiation of mitigation responses in non-laboratory settings, including long-term care facilities and schools. The protocols established in this study offer a comprehensive approach for achieving both sensitivity and rapidity in on-site SARS-CoV-2 RNA detection. Furthermore, since the RT-qPCR assay serves as the gold standard for detecting viral RNAs, the developed protocol holds potential for application to other viruses, including enteroviruses and noroviruses.

B-216 Development of a Point-of-care Multiplexed Room Temperature Stable Environmental Toxin Test

Abstract Background Hememics™ Biosensor System (HBS) is a platform technology enabling antigen and molecular testing in the field. The system consists of a reader, HemBox™, and a biosensing chip, HemChip™. The HemBox™ is a battery-operated, cell phone size with Bluetooth and WIFI module that can be integrated into the Health Management System. The biosensing chips can be programed with bio-receptors to detect pathogens in less than 5 min. This study presents performance characteristics of HBS as a rapid POC to detect toxins from environmental samples. Methods The testing protocol consists of insert a HemChip™ into the HemBox™ and mixing the sample with the buffer and apply a drop of this mixture to the chip. In less than 5 min, results are displayed on the screen of HemBox™ or transmitted to user’s cellphone via Bluetooth. Samples were prepared by spiking solutions of mud, serum, vegetable wash, and milk with Staphylococcal enterotoxin B (SEB) and ricin. Results HemChip™ was functionalized to recognize Ricin and SEB targets. For testing, these targets were mixed in various matrix. To achieve statistical significance, each sample tested represented a minimum of 10 data points. Conclusion Hememics™ Biosensor System (HBS) is designed to be the ultimate Portable Lab Diagnostics for field use. The ability to test for environmental toxins in the field is significant because it allows for quick and on-site detection of potentially harmful substances. Our biosensor system also eliminates the need for sample processing, collection and transportation, which can take significant time and resources. The results of field testing can be available almost immediately, allowing for prompt action to be taken in the case of high toxin levels.

On-site detection and laboratory verification of the presence of nerve agent biomarkers using dried blood spots

The analysis of biomedical samples is important for the investigation of the alleged exposure to chemical warfare agents. The present study aims to use dried blood spots for portable detection and laboratory verification of organophosphate poisoning. After in-vitro incubation of blood with Novichok A-230, A-232 and A-234 and sarin, a volume of 25 and 50 µL was spotted on a protein saver card. Subsequently, the dried spots were extracted and analyzed by a mobile cholinesterase test kit. In addition, butyrylcholinesterase (BChE) was isolated and digested by pepsin followed by analysis with liquid chromatography tandem mass spectrometry (LC-MS/MS). The fluoride-activated samples were analyzed by gas chromatography tandem mass spectrometry (GC–MS/MS) and LC-MS/MS. It was found that the CWA induced cholinesterase inhibition was remarkably stable in dried blood spots. Even after at least one month storage under ambient conditions, the same linear reduction was visible as function of nerve agent exposure. Additionally, nonapeptide adducts were identified by LC-MS/MS one month after exposure. Also, intact Novichok nerve agents and regenerated sarin were observed by GC–MS/MS. In addition to the stability of the sample, important benefits of the proposed method include the less invasive sample collection and safer and easier shipping and storage conditions. In conclusion, this study shows the feasibility of using on-site detection and state-of-the-art laboratory analysis of dried blood spots for unambiguous verification of nerve agent exposure.

A simple and economical fire test setup for examining the fire retardancy/extinguishing ability of water additive fire‐retardant materials on class A fires

AbstractA portable lab scale test setup (1 × 1 × 0.72 m3) with apparatus and procedure has been illustrated to test the fire extinguishability of fire retardant materials (FRMs) as water additives on class A fires. The main objective was to use selected commercial, eco‐friendly FRM powders such as hydroxides, carbonates, and clays as water additive‐based fire extinguishing agents for suppressing solid fires. FRM powders, namely, Mg(OH)2, Ca(OH)2, CaCO3, and MMT‐Clay were added to water and were mist sprayed on a wooden fire (class A) to test their fire‐suppressing ability. A comparison involving tests with only water (without any additives) was also recorded. The solutions made with FRM additives in water showed promising results in suppressing the fire in comparison to systems with only water as an extinguishing agent. Heat sink materials, such as hydroxides and clays depicted commendable performances in retarding the burning process and almost doubled the capability of fire suppression with low loading. Their heat‐absorbing nature resisted the increase in temperature and slowed down the burning process causing an increase in the total burning time of the crib and avoiding reignition. Whereas, carbonates (CaCO3) showed a faster flame out by the release of CO2 gas, which diluted the oxygen content in the surroundings. The article concludes with a discussion of the requirements for the ideal water mist additive‐based fire extinguishing agent and a recommendation that future work include validation of the laboratory‐scale method based on a comparison with full‐scale suppression data for the same additives.

Desain dan Implementasi Modul Kit Laboratorium Mikrokontroler AT89S52 dengan Single PCB, Portable dan Prospektif

This study aims to design and implement a new design of a single PCB, portable and prospective laboratory kit module. The laboratory kits made are easy to assemble, with relatively small dimensions. and suitable for use in laboratories with limited experimental space and funds. The objectives of this research are (a) creating a microcontroller trainer by creating a series of minimum systems, inputs, outputs, Analog Digital Converter (ADC), (b) system programming using the Keil C51 IDE, (c) measuring and testing trainer performance. The research method starts from making a physical trainer, programming the microcontroller and measuring circuit performance. Pulse width modulation (PWM) of DC motors and the direction of rotation of the motor can be controlled using a potentiometer. The wave that is obtained when the motor is at full speed is in the form of a straight line with a voltage of 9.12 V, while when the motor is at half-full speed, a PWM pulse wave is obtained with a voltage of 4.35 V. The test is carried out based on student practicum work on each input circuit, and the output results are all applications tested successfully as expected.

Comparing Unmanned Aerial Multispectral and Hyperspectral Imagery for Harmful Algal Bloom Monitoring in Artificial Ponds Used for Fish Farming

This work aimed to assess the potential of unmanned aerial vehicle (UAV) multi- and hyper-spectral platforms to estimate chlorophyll-a (Chl-a) and cyanobacteria in experimental fishponds in Brazil. In addition to spectral resolutions, the tested platforms differ in the price, payload, imaging system, and processing. Hyperspectral airborne surveys were conducted using a push-broom system 276-band Headwall Nano-Hyperspec camera onboard a DJI Matrice 600 UAV. Multispectral airborne surveys were conducted using a global shutter-frame 4-band Parrot Sequoia camera onboard a DJI Phantom 4 UAV. Water quality field measurements were acquired using a portable fluorometer and laboratory analysis. The concentration ranged from 14.3 to 290.7 µg/L and from 0 to 112.5 µg/L for Chl-a and cyanobacteria, respectively. Forty-one Chl-a and cyanobacteria bio-optical retrieval models were tested. The UAV hyperspectral image achieved robust Chl-a and cyanobacteria assessments, with RMSE values of 32.8 and 12.1 µg/L, respectively. Multispectral images achieved Chl-a and cyanobacteria retrieval with RMSE values of 47.6 and 35.1 µg/L, respectively, efficiently mapping the broad Chl-a concentration classes. Hyperspectral platforms are ideal for the robust monitoring of Chl-a and CyanoHABs; however, the integrated platform has a high cost. More accessible multispectral platforms may represent a trade-off between the mapping efficiency and the deployment costs, provided that the multispectral cameras offer narrow spectral bands in the 660–690 nm and 700–730 nm ranges for Chl-a and in the 600–625 nm and 700–730 nm spectral ranges for cyanobacteria.

Portable hearing laboaratory for developping and evaluating novel hearing aid algorithms

We report here on the further development of our portable hearing aid research platform achived in Phase III NIDCD project R44DC016247. We also report on a large number of academic studies using the platform around the world. The project builds on the openMHA distribution for ARM processors included in an optimized Linux system developed in our other project R01DC015429. Thus we provide a complete wearable software-hardware fast hearing aid device needed for development of new innovative solutions for assisted hearing. We refer to this device as the PHL, short for Portable Hearing Laboratory. Throught the project we have followed the requirement that the platform should be “acoustically perfect.” That is able to transmit and process signals without audible distortion or noise beyond what is required to compensate for hearing loss. Any new sophisticated algorithms (such as those based on the AI) if run on a platform of inferior quality will adapt for that inferior structire and fail to capitalize on the reach processing capabilities of the modern hearing aids. We also report on a family of devices that can be used either with PHL or with other processors to provide supperior sound; such as bunaural BTE multimicrophone headsets. Last but not least we will present new devices connecting these auxiliary devices to powefull desktop computers for laboratory studies.

Synchronization of ear-EEG and audio streams in a portable research hearing device.

Recent advancements in neuroscientific research and miniaturized ear-electroencephalography (EEG) technologies have led to the idea of employing brain signals as additional input to hearing aid algorithms. The information acquired through EEG could potentially be used to control the audio signal processing of the hearing aid or to monitor communication-related physiological factors. In previous work, we implemented a research platform to develop methods that utilize EEG in combination with a hearing device. The setup combines currently available mobile EEG hardware and the so-called Portable Hearing Laboratory (PHL), which can fully replicate a complete hearing aid. Audio and EEG data are synchronized using the Lab Streaming Layer (LSL) framework. In this study, we evaluated the setup in three scenarios focusing particularly on the alignment of audio and EEG data. In Scenario I, we measured the latency between software event markers and actual audio playback of the PHL. In Scenario II, we measured the latency between an analog input signal and the sampled data stream of the EEG system. In Scenario III, we measured the latency in the whole setup as it would be used in a real EEG experiment. The results of Scenario I showed a jitter (standard deviation of trial latencies) of below 0.1 ms. The jitter in Scenarios II and III was around 3 ms in both cases. The results suggest that the increased jitter compared to Scenario I can be attributed to the EEG system. Overall, the findings show that the measurement setup can time-accurately present acoustic stimuli while generating LSL data streams over multiple hours of playback. Further, the setup can capture the audio and EEG LSL streams with sufficient temporal accuracy to extract event-related potentials from EEG signals. We conclude that our setup is suitable for studying closed-loop EEG & audio applications for future hearing aids.