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Clinical results with photovoltaic subretinal prosthesis (PRIMA) demonstrated restoration of sight via electrical stimulation of the interneurons in degenerated retina, with resolution matching the 100 μm pixel size. Since scaling the pixels below 75 μm in the current bipolar planar geometry will significantly limit the penetration depth of the electric field and increase stimulation threshold, we explore the possibility of using smaller pixels based on a novel 3-dimensional honeycomb-shaped design. We assessed the long-term biocompatibility and stability of these arrays in rats by investigating the anatomical integration of the retina with flat and 3D implants and response to electrical stimulation over lifetime - up to 32-36 weeks post-implantation in aged rats. With both flat and 3D implants, signals elicited in the visual cortex decreased after the day of implantation by more than 3-fold, and gradually recovered over the next 12-16 weeks. With 25 μm high honeycomb walls, the majority of bipolar cells migrate into the wells, while amacrine and ganglion cells remain above the cavities, which is essential for selective network-mediated stimulation of the retina. Retinal thickness and full-field stimulation threshold with 40 μm-wide honeycomb pixels were comparable to those with planar devices - 0.05 mW/mm 2 with 10 ms pulses. However, fewer cells from the inner nuclear layer migrated into the 20 μm-wide wells, and stimulation threshold increased over 12-16 weeks, before stabilizing at about 0.08 mW/mm 2 . Such threshold is still significantly lower than 1.8 mW/mm 2 with a previous design of flat bipolar pixels, confirming the promise of the 3D honeycomb-based approach to high resolution subretinal prosthesis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Daniel Palanker reports financial support was provided by National Institutes of Health. Daniel Palanker reports financial support was provided by U.S. Department of Defense. Daniel Palanker reports financial support was provided by Air Force Office of Scientific Research. Daniel Palanker reports a relationship with Pixium Vision that includes: consulting or advisory. Ted Kamins reports a relationship with Pixium Vision that includes: consulting or advisory. Daniel Palanker has patent licensed to Pixium Vision. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Objective. Optogenetics allows the manipulation of neural circuits in vivo with high spatial and temporal precision. However, combining this precision with control over a significant portion of the brain is technologically challenging (especially in larger animal models). Approach. Here, we have developed, optimised, and tested in vivo , the Utah Optrode Array (UOA), an electrically addressable array of optical needles and interstitial sites illuminated by 181 μ LEDs and used to optogenetically stimulate the brain. The device is specifically designed for non-human primate studies. Main results. Thinning the combined μ LED and needle backplane of the device from 300 μ m to 230 μ m improved the efficiency of light delivery to tissue by 80%, allowing lower μ LED drive currents, which improved power management and thermal performance. The spatial selectivity of each site was also improved by integrating an optical interposer to reduce stray light emission. These improvements were achieved using an innovative fabrication method to create an anodically bonded glass/silicon substrate with through-silicon vias etched, forming an optical interposer. Optical modelling was used to demonstrate that the tip structure of the device had a major influence on the illumination pattern. The thermal performance was evaluated through a combination of modelling and experiment, in order to ensure that cortical tissue temperatures did not rise by more than 1 °C. The device was tested in vivo in the visual cortex of macaque expressing ChR2-tdTomato in cortical neurons. Significance. It was shown that the UOA produced the strongest optogenetic response in the region surrounding the needle tips, and that the extent of the optogenetic response matched the predicted illumination profile based on optical modelling-demonstrating the improved spatial selectivity resulting from the optical interposer approach. Furthermore, different needle illumination sites generated different patterns of low-frequency potential activity., (Creative Commons Attribution license.)

Objective: Post-operative length of hospital stay (LOS) is a valuable measure for monitoring quality of care provision, patient recovery, and guiding hospital resource management. But the impact of patient ethnicity, socio-economic deprivation as measured by the indices of multiple deprivation (IMD), and pre-existing health conditions on LOS post-anterior cervical decompression and fusion (ACDF) is under-researched in public healthcare settings., Methods: From 2013 to 2023, a retrospective study at a single center reviewed all ACDF procedures. We analyzed 14 non-clinical predictors-including demographics, comorbidities, and socio-economic status-to forecast a categorized LOS: short (≤2 days), medium (2-3 days), or long (>3 days). Three machine learning (ML) models were developed and assessed for their prediction reliability., Results: 2033 ACDF patients were analyzed; 79.44 % had a LOS ≤ 2 days. Significant predictors of LOS included patient sex (HR:0.81[0.74-0.88], p < 0.005), IMD decile (HR:1.38[1.24-1.53], p < 0.005), smoking (HR:1.24[1.12-1.38], p < 0.005), DM (HR:0.70[0.59-0.84], p < 0.005), and COPD (HR:0.66, p = 0.01). Asian patients had the highest mean LOS (p = 0.003). Testing on 407 patients, the XGBoost model achieved 80.95 % accuracy, 71.52 % sensitivity, 85.76 % specificity, 71.52 % positive predictive value, and a micro F1 score of 0.715. This model is available at: https://acdflos.streamlit.app., Conclusions: Utilizing non-clinical pre-operative parameters such as patient ethnicity, socio-economic deprivation index, and baseline comorbidities, our ML model effectively predicts postoperative LOS for patient undergoing ACDF surgeries. Yet, as the healthcare landscape evolves, such tools will require further refinement to integrate peri and post-operative variables, ensuring a holistic decision support tool., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Optogenetics has transformed studies of neural circuit function, but remains challenging to apply to non-human primates (NHPs). A major challenge is delivering intense, spatiotemporally-precise, patterned photostimulation across large volumes in deep tissue. Such stimulation is critical, for example, to modulate selectively deep-layer corticocortical feedback circuits. To address this need, we have developed the Utah Optrode Array (UOA), a 10×10 glass needle waveguide array fabricated atop a novel opaque optical interposer, and bonded to an electrically addressable µLED array. In vivo experiments with the UOA demonstrated large-scale, spatiotemporally precise, activation of deep circuits in NHP cortex. Specifically, the UOA permitted both focal (confined to single layers/columns), and widespread (multiple layers/columns) optogenetic activation of deep layer neurons, as assessed with multi-channel laminar electrode arrays, simply by varying the number of activated µLEDs and/or the irradiance. Thus, the UOA represents a powerful optoelectronic device for targeted manipulation of deep-layer circuits in NHP models., (© 2024. The Author(s).)

Objective. Retinal prosthetics offer partial restoration of sight to patients blinded by retinal degenerative diseases through electrical stimulation of the remaining neurons. Decreasing the pixel size enables increasing prosthetic visual acuity, as demonstrated in animal models of retinal degeneration. However, scaling down the size of planar pixels is limited by the reduced penetration depth of the electric field in tissue. We investigated 3-dimensional (3d) structures on top of photovoltaic arrays for enhanced penetration of the electric field, permitting higher resolution implants. Approach. 3D COMSOL models of subretinal photovoltaic arrays were developed to accurately quantify the electrodynamics during stimulation and verified through comparison to flat photovoltaic arrays. Models were applied to optimize the design of 3D electrode structures (pillars and honeycombs). Return electrodes on honeycomb walls vertically align the electric field with bipolar cells for optimal stimulation. Pillars elevate the active electrode, thus improving proximity to target neurons. The optimized 3D structures were electroplated onto existing flat subretinal prostheses. Main results. Simulations demonstrate that despite exposed conductive sidewalls, charge mostly flows via high-capacitance sputtered iridium oxide films topping the 3D structures. The 24 μ m height of honeycomb structures was optimized for integration with the inner nuclear layer cells in the rat retina, whilst 35 μ m tall pillars were optimized for penetrating the debris layer in human patients. Implantation of released 3D arrays demonstrates mechanical robustness, with histology demonstrating successful integration of 3D structures with the rat retina in-vivo . Significance . Electroplated 3D honeycomb structures produce vertically oriented electric fields, providing low stimulation thresholds, high spatial resolution, and high contrast for pixel sizes down to 20 μ m. Pillar electrodes offer an alternative for extending past the debris layer. Electroplating of 3D structures is compatible with the fabrication process of flat photovoltaic arrays, enabling much more efficient retinal stimulation., (Creative Commons Attribution license.)

In patients blinded by geographic atrophy, a subretinal photovoltaic implant with 100 µm pixels provided visual acuity closely matching the pixel pitch. However, such flat bipolar pixels cannot be scaled below 75 µm, limiting the attainable visual acuity. This limitation can be overcome by shaping the electric field with 3-dimensional (3-D) electrodes. In particular, elevating the return electrode on top of the honeycomb-shaped vertical walls surrounding each pixel extends the electric field vertically and decouples its penetration into tissue from the pixel width. This approach relies on migration of the retinal cells into the honeycomb wells. Here, we demonstrate that majority of the inner retinal neurons migrate into the 25 µm deep wells, leaving the third-order neurons, such as amacrine and ganglion cells, outside. This enables selective stimulation of the second-order neurons inside the wells, thus preserving the intraretinal signal processing in prosthetic vision. Comparable glial response to that with flat implants suggests that migration and separation of the retinal cells by the walls does not cause additional stress. Furthermore, retinal migration into the honeycombs does not negatively affect its electrical excitability, while grating acuity matches the pixel pitch down to 40 μm and reaches the 27 μm limit of natural resolution in rats with 20 μm pixels. These findings pave the way for 3-D subretinal prostheses with pixel sizes of cellular dimensions.

Background: Some individuals adopt vegetarian or plant-based diets to improve their health. Observational evidence suggests diets composed of higher amounts of animal-source foods (ASFs) are associated with increased risk for disease and early mortality. In many of these studies, those who ate fewer animal-source foods reported fewer disease risk factors and unhealthy behaviors, which could indicate bias., Purpose: This study aims to examine the relationships between ASF consumption, health behaviors, and cardiovascular disease (CVD) prevalence in a population-representative sample of U.S. civilians controlling for confounders., Methods: Respondent data were collected from the National Health and Nutrition Examination Survey (NHANES) 2013-2016 collection years. Collected data included demographics, ASF intake, healthy lifestyle variables, body mass index, and blood lipids., Results: There was a higher proportion of those with CVD history who consumed red meat (61.3%; C.I. 41.7%-77.8%), but the proportion was lower for white (23.3%; C.I. 12.6%-39.0%) and processed meat (15.4%; C.I. 6.5%-32.3%). When adjusted for sex, the odds of CVD history increased for red meat compared to processed meat consumption (OR 2.95; C.I. 1.14-7.66). Unhealthy lifestyle increased the odds of CVD history by nearly 8-fold (OR 7.8; C.I. 3.44-17.7). Individual factors including age, smoking history, body mass index, and blood lipids, and demographic factors, including education level, race, and income, were also associated with increased odds for CVD history. ROC analysis revealed 77.2% AUC for CVD history classified by individual factors (BMI ≥30 kg/m**2, ≤ 30 min moderate physical activity, smoker, fiber intake ≤25 g, dental visit more than two years ago, and age above 60 years). Three or more factors moderately predicted CVD history when optimized for sensitivity (73.4%) and specificity (71%). Adjusted for sex, the relationship between CVD and moderate physical activity became stronger possibly reflecting lifestyle changes. Despite evidence of lifestyle changes, modifiable risk factors persisted in the CVD group. CVD diagnosis in males was substantially delayed compared to females concerning the sex-specific age cutoff associated with higher risk. The healthy lifestyle group was characterized by earlier CVD diagnosis and fewer overall risk factors compared to the unhealthy lifestyle group., Conclusion: CVD history was strongly associated with demographic, lifestyle, and dietary factors. Future research should focus on multidimensional models for disease risk stratification and prevention, including individual, behavioral, and sociodemographic factors., Competing Interests: None., (© 2023 The Authors.)

Localized stimulation of the inner retinal neurons for high-acuity prosthetic vision requires small pixels and minimal crosstalk from the neighboring electrodes. Local return electrodes within each pixel limit the crosstalk, but they over-constrain the electric field, thus precluding the efficient stimulation with subretinal pixels smaller than 55 μm. Here we demonstrate a high-resolution prosthetic vision based on a novel design of a photovoltaic array, where field confinement is achieved dynamically, leveraging the adjustable conductivity of the diodes under forward bias to turn the designated pixels into transient returns. We validated the computational modeling of the field confinement in such an optically-controlled circuit by in-vitro and in-vivo measurements. Most importantly, using this strategy, we demonstrated that the grating acuity with 40 μm pixels matches the pixel pitch, while with 20 μm pixels, it reaches the 28 μm limit of the natural visual resolution in rats. This method enables customized field shaping based on individual retinal thickness and distance from the implant, paving the way to higher acuity of prosthetic vision in atrophic macular degeneration., (© 2022. The Author(s).)

Objective. PRIMA, the photovoltaic subretinal prosthesis, restores central vision in patients blinded by atrophic age-related macular degeneration (AMD), with a resolution closely matching the 100 µ m pixel size of the implant. Improvement in resolution requires smaller pixels, but the resultant electric field may not provide sufficient stimulation strength in the inner nuclear layer (INL) or may lead to excessive crosstalk between neighboring electrodes, resulting in low contrast stimulation patterns. We study the approaches to electric field shaping in the retina for prosthetic vision with higher resolution and improved contrast. Approach. We present a new computational framework, Retinal Prosthesis Simulator (RPSim), that efficiently computes the electric field in the retina generated by a photovoltaic implant with thousands of electrodes. Leveraging the PRIMA clinical results as a benchmark, we use RPSim to predict the stimulus strength and contrast of the electric field in the retina with various pixel designs and stimulation patterns. Main results. We demonstrate that by utilizing monopolar pixels as both anodes and cathodes to suppress crosstalk, most patients may achieve resolution no worse than 48 µ m. Closer proximity between the electrodes and the INL, achieved with pillar electrodes, enhances the stimulus strength and contrast and may enable 24 µ m resolution with 20 µ m pixels, at least in some patients. Significance. A resolution of 24 µ m on the retina corresponds to a visual acuity of 20/100, which is over 4 times higher than the current best prosthetic acuity of 20/438, promising a significant improvement of central vision for many AMD patients., (© 2022 IOP Publishing Ltd.)

The relationship between reproducibility standard deviation and mass fraction in food analysis has been studied in compilations of statistics from collaborative trials and from proficiency tests. There was a broad tendency for both categories of statistics to follow the Horwitz function although systematic deviations from it were easily detected at both extremes of the mass fraction range (below 10 -7 and above 10 -2 ). The two compilations were found to have very similar properties over the whole range of mass fractions, that is from about 10 -10 (0.1 ppb) upwards. This similarity has implications for the determination of detection limit., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: We sought to determine the frequency, reasons for, and factors associated with energy drink consumption in adolescents with or without attention deficit hyperactivity disorder (ADHD)., Design: Anonymous surveys were completed by 115 adolescents and their parents prior to appointments at two separate outpatient clinics (pediatric and psychiatric) over a three-month period. Trained staff provided surveys to be completed by adolescents and their parents on a voluntary basis, and all data was self-reported. Care was given to ensure adolescents and their parents completed surveys independently from each other., Results: A total of 114 adolescent surveys and 100 parent surveys were included in analysis. There was a statistically significant association between parent and adolescent consumption of energy drinks. The mean number of energy drinks consumed in the past month was lower among adolescents than among parents. The most common reason among all respondents for energy drink consumption was to promote wakefulness., Conclusion: This survey found that adolescents with parents who consumed energy drinks were more likely to drink energy drinks themselves. Trends indicate that consumption of energy drinks is increasing in the adolescent population, with potential for serious adverse events resulting from high caffeine content, warranting the need for public health awareness., Competing Interests: DISCLOSURES: The author has no conflict of interest relevant to the content of this article., (Copyright © 2021. Matrix Medical Communications. All rights reserved.)

Objective. To restore central vision in patients with atrophic age-related macular degeneration, we replace the lost photoreceptors with photovoltaic pixels, which convert light into current and stimulate the secondary retinal neurons. Clinical trials demonstrated prosthetic acuity closely matching the sampling limit of the 100 μ m pixels, and hence smaller pixels are required for improving visual acuity. However, with smaller flat bipolar pixels, the electric field penetration depth and the photodiode responsivity significantly decrease, making the device inefficient. Smaller pixels may be enabled by (a) increasing the diode responsivity using vertical p-n junctions and (b) directing the electric field in tissue vertically. Here, we demonstrate such novel photodiodes and test the retinal stimulation in a vertical electric field. Approach. Arrays of silicon photodiodes of 55, 40, 30, and 20 μ m in width, with vertical p-n junctions, were fabricated. The electric field in the retina was directed vertically using a common return electrode at the edge of the device. Optical and electronic performance of the diodes was characterized in-vitro , and retinal stimulation threshold measured by recording the visually evoked potentials in rats with retinal degeneration. Main results. The photodiodes exhibited sufficiently low dark current (<10 pA) and responsivity at 880 nm wavelength as high as 0.51 A W -1 , with 85% internal quantum efficiency, independent of pixel size. Field mapping in saline demonstrated uniformity of the pixel performance in the array. The full-field stimulation threshold was as low as 0.057±0.029mW mm -2 with 10 ms pulses, independent of pixel size. Significance. Photodiodes with vertical p-n junctions demonstrated excellent charge collection efficiency independent of pixel size, down to 20 μ m. Vertically oriented electric field provides a stimulation threshold that is independent of pixel size. These results are the first steps in validation of scaling down the photovoltaic pixels for subretinal stimulation., (© 2021 IOP Publishing Ltd.)

Due to the shortage of occupational therapists (OTs) in Haiti and over 800,000 individuals with disabilities, most occupational therapy assessments and interventions are provided by OTs on short-term medical missions (STMMs). Learning which methods OT use to provide assessments and interventions during these STMMs is the first step to understanding how to facilitate follow-up and carry-over for clients and ensure longevity for STMMs in Haiti. This study used a cross-sectional, descriptive design to gather data on methods used by OTs. Thirty-three OTs, who travelled to Haiti on STMMs, completed a 16-question, online survey. The most common method provided by OTs was education to patients, caregivers, and local providers. Training of Haitian rehabilitation technicians was also prevalent. There was an association between the years of the OTs' clinical experience and the effort of OTs to train local providers, but this result was not statistically significant. Further research should be implemented on specific methods that can be used in the absence or shortage of Haitian OTs to ensure follow-up for Haitian clients. The sharing of data regarding OT methods on STMMs will promote evidence-based, client-centered, and cost-effective therapy to enhance effective client outcomes., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Sheelagh M. Schlegel and Kathleen Mathieson.)

In vivo electrophysiology is the gold standard technique used to investigate sub-second neural dynamics in freely behaving animals. However, monitoring cell-type-specific population activity is not a trivial task. Over the last decade, fiber photometry based on genetically encoded calcium indicators (GECIs) has been widely adopted as a versatile tool to monitor cell-type-specific population activity in vivo . However, this approach suffers from low temporal resolution. Here, we combine these two approaches to monitor both sub-second field potentials and cell-type-specific population activity in freely behaving mice. By developing an economical custom-made system and constructing a hybrid implant of an electrode and a fiber optic cannula, we simultaneously monitor artifact-free mesopontine field potentials and calcium transients in cholinergic neurons across the sleep-wake cycle. We find that mesopontine cholinergic activity co-occurs with sub-second pontine waves, called P-waves, during rapid eye movement sleep. Given the simplicity of our approach, simultaneous electrophysiological recording and cell-type-specific imaging provides a novel and valuable tool for interrogating state-dependent neural circuit dynamics in vivo ., (Copyright © 2020 Patel, McAlinden, Mathieson and Sakata.)

Purpose: The purpose of this quantitative comparative study was to examine the possible relationship between nicotine replacement therapy (NRT) and cardiac disorder risk by comparing the rates of cardiac disorder risk of NRT with cardiac disorder risk of non-replacement drugs among smokers seeking smoking cessation., Methods: The study used retrospective quantitative design, which involved the collection of secondary data from the adverse event reporting system (FAERS) database of the U.S Food and Drug Administration (FDA). Rates of cardiac disorder were compared between the NRT group and non- NRT (varenicline and bupropion) group. Statistical analyses involved using a 2x2 contingency table and logistic regression to calculate odds ratio (reporting odds ratio (ROR))., Results and Discussion: Unadjusted ROR was 0.45 (95% confidence interval [CI] 0.28, 0.70). With age and sex as confounding factors, the smokers in the NRT group still had lower odds of having cardiac disorder risk than the non-NRT group (adjusted ROR=0.44, 95% CI 0.28, 0.70)., Conclusion: Our study findings showed lower cardiac disorder risk with the NRT group compared to the non-NRT (varenicline and bupropion) group. While the study did not aim to undermine either using NRT or non-NRT for smoking cessation therapy to prevent smoking illness, the study results offer informed findings that could potentially improve current smoking cessation management using NRT intervention among smokers and enhance smokers' health outcome. Despite the negative signal detection of cardiac disorder risk with NRT as compared to non-NRT in final findings, we still recommend further research on the causal relationship between NRT and non-NRT and cardiac disorder risk., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: Retinal prostheses aim to restore sight by electrically stimulating the surviving retinal neurons. In clinical trials of the current retinal implants, prosthetic visual acuity does not exceed 20/550. However, to provide meaningful restoration of central vision in patients blinded by age-related macular degeneration (AMD), prosthetic acuity should be at least 20/200, necessitating a pixel pitch of about 50 µm or lower. With such small pixels, stimulation thresholds are high due to limited penetration of electric field into tissue. Here, we address this challenge with our latest photovoltaic arrays and evaluate their performance in vivo., Approach: We fabricated photovoltaic arrays with 55 and 40 µm pixels (a) in flat geometry, and (b) with active electrodes on 10 µm tall pillars. The arrays were implanted subretinally into rats with degenerate retina. Stimulation thresholds and grating acuity were evaluated using measurements of the visually evoked potentials (VEP)., Main Results: With 55 µm pixels, we measured grating acuity of 48  ±  11 µm, which matches the linear pixel pitch of the hexagonal array. This geometrically corresponds to a visual acuity of 20/192 in a human eye, matching the threshold of legal blindness in the US (20/200). With pillar electrodes, the irradiance threshold was nearly halved, and duration threshold reduced by more than three-fold, compared to flat pixels. With 40 µm pixels, VEP was too low for reliable measurements of the grating acuity, even with pillar electrodes., Significance: While being helpful for treating a complete loss of sight, current prosthetic technologies are insufficient for addressing the leading cause of untreatable visual impairment-AMD. Subretinal photovoltaic arrays may provide sufficient visual acuity for restoration of central vision in patients blinded by AMD.

High-resolution visual prostheses require small, densely packed pixels, but limited penetration depth of the electric field formed by a planar electrode array constrains such miniaturization. We present a novel honeycomb configuration of an electrode array with vertically separated active and return electrodes designed to leverage migration of retinal cells into voids in the subretinal space. Insulating walls surrounding each pixel decouple the field penetration depth from the pixel width by aligning the electric field vertically, enabling a decrease of the pixel size down to cellular dimensions. We demonstrate that inner retinal cells migrate into the 25 μm deep honeycomb wells as narrow as 18 μm, resulting in more than half of these cells residing within the electrode cavities. Immune response to honeycombs is comparable to that with planar arrays. Modeled stimulation threshold current density with honeycombs does not increase substantially with reduced pixel size, unlike quadratic increase with planar arrays. This 3-D electrode configuration may enable functional restoration of central vision with acuity better than 20/100 for millions of patients suffering from age-related macular degeneration.

We present an electrically addressable optrode array capable of delivering light to 181 sites in the brain, each providing sufficient light to optogenetically excite thousands of neurons in vivo , developed with the aim to allow behavioral studies in large mammals. The device is a glass microneedle array directly integrated with a custom fabricated microLED device, which delivers light to 100 needle tips and 81 interstitial surface sites, giving two-level optogenetic excitation of neurons in vivo . Light delivery and thermal properties are evaluated, with the device capable of peak irradiances > 80    mW / mm 2 per needle site. The device consists of an array of 181 80    μ m × 80    μ m 2 microLEDs, fabricated on a 150 - μ m -thick GaN-on-sapphire wafer, coupled to a glass needle array on a 150 - μ m thick backplane. A pinhole layer is patterned on the sapphire side of the microLED array to reduce stray light. Future designs are explored through optical and thermal modeling and benchmarked against the current device.

Objectives: This paper explores the relationship between speech therapy intensity and parent satisfaction with speech therapy (ST) in children with Phelan-McDermid Syndrome (P-MS), a rare genetic disorder. Methods: ST intensity (ST Dose [minutes per session])  ×  (ST Dose Frequency)  ×  (ST Length [years]) and parent satisfaction (modified PSQ-18) with ST were measured by online questionnaire. Non-parametric correlation, partial correlation, and linear regression calculations were performed. Results: Significant correlations between ST Dose and parent satisfaction were observed in the subscales of Time Spent with ST (r = .36, p < .05) and Accessibility and Convenience ( r  = .40, p  < .05) in children with P-MS controlling for child age. ST Dose was also a significant independent predictor of parent satisfaction with ST in specific subscales. Conclusion: Significant positive correlation and linear regression results indicate increases in ST Dose (minutes per session) represent a mechanism for increasing parent satisfaction with ST in children with P-MS., (© The British Society of Developmental Disabilities 2019.)

Objective: This study evaluated how Tactical Emergency Casualty Care (TECC) training prepared law enforcement officers (LEOs) with the tools necessary to provide immediate, on-scene medical care to successfully stabilize victims of trauma., Methods: This was a retrospective, de-identified study using a seven-item Fairfax County (Virginia USA) TECC After-Action Questionnaire and Arlington County (Virginia USA) police reports., Results: Forty-six encounters were collected from 2015 through 2016. Eighty-four percent (n=39) of the encounters were from TECC After-Action Questionnaires and 15% (n=7) were from police reports. The main injuries included 13% (n=6) arterial bleeds, 46% (n=21) mild/moderate bleeds, 37% (n=17) large wounds, 20% (n=9) penetrating chest wounds, and 13% (n=6) open abdominal wounds. One-hundred percent of officers reported success in stabilizing victim injuries. Seventy-four percent of officers (n=26) did not encounter problems caring for a patient while 26% (n=9) encountered a problem. Ninety-seven percent (n=37/38) answered Yes, the training was sufficient, and three percent (n=1) indicated it was OK., Conclusion: This is the most comprehensive study of TECC use among LEOs to date that supports the importance of TECC training for all LEOs in prehospital trauma care. Results of this study showed TECC training prepared LEOs with the operational tools necessary to provide immediate, on-scene medical care to successfully stabilize victims of trauma. Continuing to train increasing numbers of LEOs in TECC is key to saving the lives of victims of trauma in the future. RothschildHR, MathiesonK. Effects of Tactical Emergency Casualty Care training for law enforcement officers. Prehosp Disaster Med. 2018;33(5):495-500.

Objective: High-resolution prosthetic vision requires dense stimulating arrays with small electrodes. However, such miniaturization reduces electrode capacitance and penetration of electric field into tissue. We evaluate potential solutions to these problems with subretinal implants based on utilization of pillar electrodes., Approach: To study integration of three-dimensional (3D) implants with retinal tissue, we fabricated arrays with varying pillar diameter, pitch, and height, and implanted beneath the degenerate retina in rats (Royal College of Surgeons, RCS). Tissue integration was evaluated six weeks post-op using histology and whole-mount confocal fluorescence imaging. The electric field generated by various electrode configurations was calculated in COMSOL, and stimulation thresholds assessed using a model of network-mediated retinal response., Main Results: Retinal tissue migrated into the space between pillars with no visible gliosis in 90% of implanted arrays. Pillars with 10 μm height reached the middle of the inner nuclear layer (INL), while 22 μm pillars reached the upper portion of the INL. Electroplated pillars with dome-shaped caps increase the active electrode surface area. Selective deposition of sputtered iridium oxide onto the cap ensures localization of the current injection to the pillar top, obviating the need to insulate the pillar sidewall. According to computational model, pillars having a cathodic return electrode above the INL and active anodic ring electrode at the surface of the implant would enable six times lower stimulation threshold, compared to planar arrays with circumferential return, but suffer from greater cross-talk between the neighboring pixels., Significance: 3D electrodes in subretinal prostheses help reduce electrode-tissue separation and decrease stimulation thresholds to enable smaller pixels, and thereby improve visual acuity of prosthetic vision.

Subretinal prostheses aim at restoring sight to patients blinded by photoreceptor degeneration using electrical activation of the surviving inner retinal neurons. Today, such implants deliver visual information with low-frequency stimulation, resulting in discontinuous visual percepts. We measured retinal responses to complex visual stimuli delivered at video rate via a photovoltaic subretinal implant and by visible light. Using a multielectrode array to record from retinal ganglion cells (RGCs) in the healthy and degenerated rat retina ex vivo, we estimated their spatiotemporal properties from the spike-triggered average responses to photovoltaic binary white noise stimulus with 70-μm pixel size at 20-Hz frame rate. The average photovoltaic receptive field size was 194 ± 3 μm (mean ± SE), similar to that of visual responses (221 ± 4 μm), but response latency was significantly shorter with photovoltaic stimulation. Both visual and photovoltaic receptive fields had an opposing center-surround structure. In the healthy retina, ON RGCs had photovoltaic OFF responses, and vice versa. This reversal is consistent with depolarization of photoreceptors by electrical pulses, as opposed to their hyperpolarization under increasing light, although alternative mechanisms cannot be excluded. In degenerate retina, both ON and OFF photovoltaic responses were observed, but in the absence of visual responses, it is not clear what functional RGC types they correspond to. Degenerate retina maintained the antagonistic center-surround organization of receptive fields. These fast and spatially localized network-mediated ON and OFF responses to subretinal stimulation via photovoltaic pixels with local return electrodes raise confidence in the possibility of providing more functional prosthetic vision. NEW & NOTEWORTHY Retinal prostheses currently in clinical use have struggled to deliver visual information at naturalistic frequencies, resulting in discontinuous percepts. We demonstrate modulation of the retinal ganglion cells (RGC) activity using complex spatiotemporal stimuli delivered via subretinal photovoltaic implant at 20 Hz in healthy and in degenerate retina. RGCs exhibit fast and localized ON and OFF network-mediated responses, with antagonistic center-surround organization of their receptive fields.

Understanding the role of neurons in encoding and transmitting information is a major goal in neuroscience. This requires insight on the data-rich neuronal spiking patterns combined, ideally, with morphology and genetic identity. Electrophysiologists have long experienced the trade-offs between anatomically-accurate single-cell recording techniques and high-density multi-cellular recording methods with poor anatomical correlations. In this study, we present a novel technique that combines large-scale micro-electrode array recordings with genetic identification and the anatomical location of the retinal ganglion cell soma. This was obtained through optogenetic stimulation and subsequent confocal imaging of genetically targeted retinal ganglion cell sub-populations in the mouse. With the many molecular options available for optogenetic gene expression, we view this method as a versatile tool for matching function to genetic classifications, which can be extended to include morphological information if the density of labelled cells is at the correct level.

Purpose: Interprofessional education (IPE) has been shown to improve collaboration in the workforce, ultimately improving patient care. The purpose of this study was to evaluate physician assistant (PA) educators' attitudes toward IPE and interprofessional (IP) health care teams., Methods: An online survey was sent to 1198 PA educators. The survey assessed 3 domains: attitudes toward IPE, attitudes toward IP health care teams, and attitudes toward IP learning in the academic setting., Results: Most participants were involved in some form of IPE. Faculty attitudes were positive in all 3 domains but were more favorable toward IPE., Conclusions: The positive attitudes held by PA faculty members may change the way in which curricula are conceived and delivered, influencing IP collaboration of future health care providers.

Introduction: Health care access for medically underserved patients managing chronic conditions is challenging. While telemedicine can support patient education and engagement, the "digital divide" may be particularly problematic among the medically underserved. This study evaluated physical access to digital devices, use of e-mail and social media tools, and perceptions of telemedicine among American Indian (AI) patients with diabetes mellitus (DM)., Methods: Survey data were collected from AI patients with DM during teleophthalmology exams., Results: Eighty-eight percent of patients had access to digital device(s), 70% used e-mail, and 56% used social media. Younger age and greater education were positively associated with e-mail and social media use (p &lt; .05). Most (60%) considered telemedicine an excellent medium for health-related patient education., Discussion: American Indian patients with DM had access enabling patient education via telemedicine. Future work should examine patient technology preferences and effectiveness of technology-based education in improving outcomes among medically underserved populations.

Patients with complex medical conditions require collaboration among multiple health care providers, and dental hygienists must be prepared to communicate effectively with medical providers to provide comprehensive quality patient care. The aim of this study was to assess U.S. dental hygiene students' attitudes about interprofessional collaboration (IPC) and identify any differences based on age, year in program, and program location. Participants were limited to students enrolled in dental hygiene associate degree programs across the United States. In response to an email soliciting participation sent to all dental hygiene program directors, 504 students completed the Interdisciplinary Education Perception Scale (IEPS) online (response rate could not be calculated). The IEPS is a validated survey that measures attitudes about interprofessional collaboration. The majority of the respondents were female (97%) and under 30 years of age (74.6%). Their mean scores indicated positive attitudes about IPC. There were no statistically significant differences in scores by age (p=0.700) or program location (p=0.527). There were also no statistically significant differences between first- and second-year students for total mean scores (p=0.106); for the competency and autonomy subscale (p=0.125); and for the perception of actual cooperation subscale (p=0.890). There was a statistically significant difference between first- and second-year students on the perception of actual cooperation subscale, with first-year students scoring higher than second-year students (p=0.016). This study's findings of positive attitudes about IPC and that age and program location had little bearing on the responses suggest that associate degree dental hygiene students may welcome the interprofessional education that will prepare them for practice in the future.

Objective: To evaluate plasma-enhanced, chemically vapor deposited (PECVD) amorphous silicon carbide (α-SiC:H) as a protective coating for retinal prostheses and other implantable devices, and to study their failure mechanisms in vivo., Approach: Retinal prostheses were implanted in rats sub-retinally for up to 1 year. Degradation of implants was characterized by optical and scanning electron microscopy. Dissolution rates of SiC, SiN x and thermal SiO2 were measured in accelerated soaking tests in saline at 87 °C. Defects in SiC films were revealed and analyzed by selectively removing the materials underneath those defects., Main Results: At 87 °C SiN x dissolved at 18.3 ± 0.3 nm d(-1), while SiO2 grown at high temperature (1000 °C) dissolved at 0.104 ± 0.008 nm d(-1). SiC films demonstrated the best stability, with no quantifiable change after 112 d. Defects in thin SiC films appeared primarily over complicated topography and rough surfaces., Significance: SiC coatings demonstrating no erosion in accelerated aging test for 112 d at 87 °C, equivalent to about 10 years in vivo, can offer effective protection of the implants. Photovoltaic retinal prostheses with PECVD SiC coatings exhibited effective protection from erosion during the 4 month follow-up in vivo. The optimal thickness of SiC layers is about 560 nm, as defined by anti-reflective properties and by sufficient coverage to eliminate defects.

Controlling neural circuits is a powerful approach to uncover a causal link between neural activity and behaviour. Optogenetics has been widely adopted by the neuroscience community as it offers cell-type-specific perturbation with millisecond precision. However, these studies require light delivery in complex patterns with cellular-scale resolution, while covering a large volume of tissue at depth in vivo. Here we describe a novel high-density silicon-based microscale light-emitting diode (μLED) array, consisting of up to ninety-six 25 μm-diameter μLEDs emitting at a wavelength of 450 nm with a peak irradiance of 400 mW/mm(2). A width of 100 μm, tapering to a 1 μm point, and a 40 μm thickness help minimise tissue damage during insertion. Thermal properties permit a set of optogenetic operating regimes, with ~0.5 °C average temperature increase. We demonstrate depth-dependent activation of mouse neocortical neurons in vivo, offering an inexpensive novel tool for the precise manipulation of neural activity.

The purpose of this study was to survey health service workers regarding their radiation safety knowledge and practice. Participants were health service workers (n = 721) who received an anonymous online survey by email to test their radiation safety knowledge. A knowledge test of 15 questions was completed by 412 respondents. The overall average percent correct was 77.9%. Health physicists/medical physicists had the highest average percent score (93.5%), while physician assistants scored the lowest (60.0%). Of all the respondents, only 64.0% reported they participated in periodic radiation safety training at their place of employment. The most common topic selected where participants wanted additional training was in biological effects of radiation (41.0%). In conclusion, radiation safety training and education needs to be developed and planned effectively. Areas or specialties with poor radiation safety knowledge need to be addressed with corresponding safety measures.

Photovoltaic conversion of pulsed light into pulsed electric current enables optically-activated neural stimulation with miniature wireless implants. In photovoltaic retinal prostheses, patterns of near-infrared light projected from video goggles onto subretinal arrays of photovoltaic pixels are converted into patterns of current to stimulate the inner retinal neurons. We describe a model of these devices and evaluate the performance of photovoltaic circuits, including the electrode-electrolyte interface. Characteristics of the electrodes measured in saline with various voltages, pulse durations, and polarities were modeled as voltage-dependent capacitances and Faradaic resistances. The resulting mathematical model of the circuit yielded dynamics of the electric current generated by the photovoltaic pixels illuminated by pulsed light. Voltages measured in saline with a pipette electrode above the pixel closely matched results of the model. Using the circuit model, our pixel design was optimized for maximum charge injection under various lighting conditions and for different stimulation thresholds. To speed discharge of the electrodes between the pulses of light, a shunt resistor was introduced and optimized for high frequency stimulation.

Purpose: Prosthetic restoration of partial sensory loss leads to interactions between artificial and natural inputs. Ideally, the rehabilitation should allow perceptual fusion of the two modalities. Here we studied the interactions between normal and prosthetic vision in a rodent model of local retinal degeneration., Methods: Implantation of a photovoltaic array in the subretinal space of normally sighted rats induced local degeneration of the photoreceptors above the chip, and the inner retinal neurons in this area were electrically stimulated by the photovoltaic implant powered by near-infrared (NIR) light. We studied prosthetic and natural visually evoked potentials (VEP) in response to simultaneous stimulation by NIR and visible light patterns., Results: We demonstrate that electrical and natural VEPs summed linearly in the visual cortex, and both responses decreased under brighter ambient light. Responses to visible light flashes increased over 3 orders of magnitude of contrast (flash/background), while for electrical stimulation the contrast range was limited to 1 order of magnitude. The maximum amplitude of the prosthetic VEP was three times lower than the maximum response to a visible flash over the same area on the retina., Conclusions: Ambient light affects prosthetic responses, albeit much less than responses to visible stimuli. Prosthetic representation of contrast in the visual scene can be encoded, to a limited extent, by the appropriately calibrated stimulus intensity, which also depends on the ambient light conditions. Such calibration will be important for patients combining central prosthetic vision with natural peripheral sight, such as in age-related macular degeneration.

Purpose: To evaluate the contrast sensitivity of a degenerate retina stimulated by a photovoltaic subretinal prosthesis, and assess the impact of low contrast sensitivity on transmission of visual information., Methods: We measure ex vivo the full-field contrast sensitivity of healthy rat retina stimulated with white light, and the contrast sensitivity of degenerate rat retina stimulated with a subretinal prosthesis at frequencies exceeding flicker fusion (>20 Hz). Effects of eye movements on retinal ganglion cell (RGC) activity are simulated using a linear-nonlinear model of the retina., Results: Retinal ganglion cells adapt to high frequency stimulation of constant intensity, and respond transiently to changes in illumination of the implant, exhibiting responses to ON-sets, OFF-sets, and both ON- and OFF-sets of light. The percentage of cells with an OFF response decreases with progression of the degeneration, indicating that OFF responses are likely mediated by photoreceptors. Prosthetic vision exhibits reduced contrast sensitivity and dynamic range, with 65% contrast changes required to elicit responses, as compared to the 3% (OFF) to 7% (ON) changes with visible light. The maximum number of action potentials elicited with prosthetic stimulation is at most half of its natural counterpart for the ON pathway. Our model predicts that for most visual scenes, contrast sensitivity of prosthetic vision is insufficient for triggering RGC activity by fixational eye movements., Conclusions: Contrast sensitivity of prosthetic vision is 10 times lower than normal, and dynamic range is two times below natural. Low contrast sensitivity and lack of OFF responses hamper delivery of visual information via a subretinal prosthesis.

The function of a neural circuit is shaped by the computations performed by its interneurons, which in many cases are not easily accessible to experimental investigation. Here, we elucidate the transformation of visual signals flowing from the input to the output of the primate retina, using a combination of large-scale multi-electrode recordings from an identified ganglion cell type, visual stimulation targeted at individual cone photoreceptors, and a hierarchical computational model. The results reveal nonlinear subunits in the circuity of OFF midget ganglion cells, which subserve high-resolution vision. The model explains light responses to a variety of stimuli more accurately than a linear model, including stimuli targeted to cones within and across subunits. The recovered model components are consistent with known anatomical organization of midget bipolar interneurons. These results reveal the spatial structure of linear and nonlinear encoding, at the resolution of single cells and at the scale of complete circuits.

The increasing prevalence and risk of complications from diabetes necessitate patient participation and attentiveness to select appropriate foods, perform regular physical activity, and be active in diabetes management and self-maintenance. Diabetes is often largely asymptomatic; consequently, early diagnosis and treatment are necessary. Inmates are a unique population challenged by the increased prevalence of chronic conditions including diabetes. Diabetes standards for inmates contain diagnostic and treatment management guidelines that incorporate personal glucose monitoring for insulin users. In December 2009, the Federal Bureau of Prisons initiated a program to distribute glucose meters to insulin-dependent inmates to facilitate self-monitoring blood glucose. The purpose of this study was to evaluate the effect of these glucose meters on hemoglobin A1c levels., (© The Author(s) 2015.)

Loss of photoreceptors during retinal degeneration leads to blindness, but information can be reintroduced into the visual system using electrical stimulation of the remaining retinal neurons. Subretinal photovoltaic arrays convert pulsed illumination into pulsed electric current to stimulate the inner retinal neurons. Since required irradiance exceeds the natural luminance levels, an invisible near-infrared (915 nm) light is used to avoid photophobic effects. We characterized the thresholds and dynamic range of cortical responses to prosthetic stimulation with arrays of various pixel sizes and with different number of photodiodes. Stimulation thresholds for devices with 140 μm pixels were approximately half those of 70 μm pixels, and with both pixel sizes, thresholds were lower with 2 diodes than with 3 diodes per pixel. In all cases these thresholds were more than two orders of magnitude below the ocular safety limit. At high stimulation frequencies (>20 Hz), the cortical response exhibited flicker fusion. Over one order of magnitude of dynamic range could be achieved by varying either pulse duration or irradiance. However, contrast sensitivity was very limited. Cortical responses could be detected even with only a few illuminated pixels. Finally, we demonstrate that recording of the corneal electric potential in response to patterned illumination of the subretinal arrays allows monitoring the current produced by each pixel, and thereby assessing the changes in the implant performance over time., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Optogenetics has proven to be a revolutionary technology in neuroscience and has advanced continuously over the past decade. However, optical stimulation technologies for in vivo need to be developed to match the advances in genetics and biochemistry that have driven this field. In particular, conventional approaches for in vivo optical illumination have a limitation on the achievable spatio-temporal resolution. Here we utilize a sapphire-based microscale gallium nitride light-emitting diode (μLED) probe to activate neocortical neurons in vivo. The probes were designed to contain independently controllable multiple μLEDs, emitting at 450 nm wavelength with an irradiance of up to 2 W/mm(2). Monte-Carlo stimulations predicted that optical stimulation using a μLED can modulate neural activity within a localized region. To validate this prediction, we tested this probe in the mouse neocortex that expressed channelrhodopsin-2 (ChR2) and compared the results with optical stimulation through a fiber at the cortical surface. We confirmed that both approaches reliably induced action potentials in cortical neurons and that the μLED probe evoked strong responses in deep neurons. Due to the possibility to integrate many optical stimulation sites onto a single shank, the μLED probe is thus a promising approach to control neurons locally in vivo.

Patients with retinal degeneration lose sight due to the gradual demise of photoreceptors. Electrical stimulation of surviving retinal neurons provides an alternative route for the delivery of visual information. We demonstrate that subretinal implants with 70-μm-wide photovoltaic pixels provide highly localized stimulation of retinal neurons in rats. The electrical receptive fields recorded in retinal ganglion cells were similar in size to the natural visual receptive fields. Similarly to normal vision, the retinal response to prosthetic stimulation exhibited flicker fusion at high frequencies, adaptation to static images and nonlinear spatial summation. In rats with retinal degeneration, these photovoltaic arrays elicited retinal responses with a spatial resolution of 64 ± 11 μm, corresponding to half of the normal visual acuity in healthy rats. The ease of implantation of these wireless and modular arrays, combined with their high resolution, opens the door to the functional restoration of sight in patients blinded by retinal degeneration.