gebhart/patrepeval huggingface dataset:
Power Efficient Multiple Voltage Stimulation for Implantable Retinal Prosthesis (2005)

Electrical stimulation of retinal neurons has been identified as a form of visual prosthesis to restore vision in blind patients affected by Retinitis Pigmentosa (RP) and Age-related Macular Degeneration (AMD). Experiments on a successful prosthetic device in a chronically implanted patient indicate that the threshold current varies depending on the retinal region. Power can be saved by reducing the stimulus current in these sites. Further power savings can be obtained by reducing the supply voltage for these sites. This paper proposes a multiple voltage scheme in a retinal stimulator for reducing the power dissipation. An analysis of power dissipation is performed that helps to identify the stimulus range where maximum power savings is possible. A prototype retinal microstimulator IC is fabricated in CMOS technology that is capable of delivering 600/spl mu/A bi-phasic pulses. The performance of the chip is verified under multiple voltages and measurement results of the chip are presented.
Radiation effects on ferroelectric thin-film memories: Retention failure mechanisms (1989)

Ferroelectric thin-film (200–350 nm) memories were fabricated and tested. Two materials were used as memory cells: potassium nitrate (KNO3) and lead zirconate titanate (PbZr0.54Ti0.46O3, usually abbreviated as PZT). These devices were tested as arrays deposited either by thermal evaporation (in the case of KNO3) or sputtered films (PZT). Fully packaged devices were tested to determine switching speed and polarization (switched charge) as functions of temperature and applied voltage. Radiation hardness was also tested for both dose rate and total dose. The switching kinetics were investigated in considerable detail and found to confirm the theory of Ishibashi. The dimensionality of domain growth for the switching process in KNO3 lowers from 2.3 before irradiation to 1.6 after 0.5 Mrad. For PZT rad hardness exceeds 5 Mrad total dose and 2×1011 rad/s. A surprising result was that the hysteresis curves for all of the PZT samples became more symmetric after 5 Mrad irradiation; this is interpreted as a destruction of internal biasing fields. All PZT memories continued to function after 5 Mrad, but 2 out of 8 of those stored under short-circuited conditions failed to retain information. An explanation of the retention failure of the short-circuited cells is given in terms of space-charge and well-known electret effects.
Outdoor Path Labeling Using Polynomial Mahalanobis Distance (2006)

Autonomous robot navigation in outdoor environments remains a challenging and unsolved problem. A key issue is our ability to identify safe or navigable paths far enough ahead of the robot to allow smooth trajectories at acceptable speeds. Colour or texture-based labeling of safe path regions in image sequences is one way to achieve this far field prediction. A challenge for classifiers identifying path and nonpath regions is to make meaningful comparisons of feature vectors at pixels or over a window. Most simple distance metrics cannot use all the information available and therefore the resulting labeling does not tightly capture the visible path. We introduce a new Polynomial Mahalanobis Distance and demonstrate its ability to capture the properties of an initial positive path sample and produce accurate path segmentation with few outliers. Experiments show the method's effectiveness for path segmentation in natural scenes using both colour and texture feature vectors. The new metric is compared with classifications based on Euclidean and standard Mahalanobis distance and produces superior results.
Ligand substitution photochemistry of monosubstituted derivatives of tungsten hexacarbonyl (1977)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLigand substitution photochemistry of monosubstituted derivatives of tungsten hexacarbonylR. Marc. Dahlgren and Jeffrey I. ZinkCite this: Inorg. Chem. 1977, 16, 12, 3154–3161Publication Date (Print):December 1, 1977Publication History Published online1 May 2002Published inissue 1 December 1977https://pubs.acs.org/doi/10.1021/ic50178a034https://doi.org/10.1021/ic50178a034research-articleACS PublicationsRequest reuse permissionsArticle Views460Altmetric-Citations55LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Large Diode Sensitivity of CoFeB/MgO/CoFeB Magnetic Tunnel Junctions (2010)

We report on rf current-induced excitation of the ferromagnetic resonance in CoFeB/MgO/CoFeB magnetic tunnel junctions under a perpendicular magnetic field. By choosing an appropriate external field and using an Fe-rich CoFeB free layer, the effective precession of the free layer could be excited. In a measurement of homodyne detection, a large dc output voltage of 180 µV was obtained when an rf signal power of -25 dBm was applied. The sensitivity of this junction, as an rf rectifier, reaches about 170 mV/mW (280 mV/mW after impedance matching correction), which is the same order compared with that of a Schottky diode operated at room temperature.
Power pedal as a man-machine synergy effector &#x2014; Bipedal walking with human skill and robot power &#x2014; (2008)

We have proposed the concept of Man-Machine Synergy Effectors. These are high-performance tools for human use, which are realized by introducing robot technology. It becomes possible to perform conventionally impossible tasks by human alone or robot alone, because the system synergizes better assets of both parties. In this paper, the concept of Man-Machine Synergy Effector is described. Then, the Power Pedal is introduced as a prototype of Man-Machine Synergy Effector for human lower extremities, which amplifies human leg power intuitively.
Putative Synthetic Cannabinoids MEPIRAPIM, 5F-BEPIRAPIM (NNL-2), and Their Analogues Are T-Type Calcium Channel (CaV3) Inhibitors (2022)

Synthetic cannabinoid receptor agonists (SCRAs) are a large and growing class of new psychoactive substances (NPSs). Two recently identified compounds, MEPIRAPIM and 5F-BEPIRAPIM (NNL-2), have not been confirmed as agonists of either cannabinoid receptor subtype but share structural similarities with both SCRAs and a class of T-type calcium channel (Ca<sub>V</sub>3) inhibitors under development as new treatments for epilepsy and pain. In this study, MEPIRAPIM and 5F-BEPIRAPIM and 10 systematic analogues were synthesized, analytically characterized, and pharmacologically evaluated using <i>in vitro</i> cannabinoid receptor and Ca<sub>V</sub>3 assays. Several compounds showed micromolar affinities for CB<sub>1</sub> and/or CB<sub>2</sub>, with several functioning as low potency agonists of CB<sub>1</sub> and CB<sub>2</sub> in a membrane potential assay. 5F-BEPIRAPIM and four other derivatives were identified as potential Ca<sub>V</sub>3 inhibitors through a functional calcium flux assay (>70% inhibition), which was further confirmed using whole-cell patch-clamp electrophysiology. Additionally, MEPIRAPIM and 5F-BEPIRAPIM were evaluated <i>in vivo</i> using a cannabimimetic mouse model. Despite detections of MEPIRAPIM and 5F-BEPIRAPIM in the NPS market, only the highest MEPIRAPIM dose (30 mg/kg) elicited a mild hypothermic response in mice, with no hypothermia observed for 5F-BEPIRAPIM, suggesting minimal central CB<sub>1</sub> receptor activity.
A Loss and Queuing-Delay Controller for Router Buffer Management (2006)

Active queue management (AQM) in routers has been proposed as a solution to some of the scalability issues associated with TCP’s pure end-to-end approach to congestion control. However, beyond congestion control, controlling queues in routers is important because unstable router queues can cause poor application performance. Existing AQM schemes explicitly try to control router queues by probabilistically dropping (or marking) packets. We argue that while controlling router queues is important, this control needs to be tempered by a consideration of the overall lossrate at the router. Solely attempting to control queue length can induce loss-rates that have as negative an effect on application and network performance as the large queues that existing AQM schemes were trying to avoid. Thus controlling queue length without regard to loss-rate can be counterproductive. In this work we demonstrate that by jointly controlling queue length and loss-rate, both network and application performance are improved. We present a novel AQM design that attempts to simultaneously optimize queue length and loss-rate. Our algorithm, called loss and queuing delay control (LQD), is a control theoretic scheme that explicitly treats loss-rate as a control parameter. LQD is shown to provide stable control analytically and is evaluated empirically by comparing its performance against other control theoretic AQM designs (PI and REM). The results of evaluation in a laboratory testbed under realistic traffic mixes and loads show that LQD results in lower overall loss rates and that applications see lower average queue lengths than with PI or REM.
Neutral hip position for the oblique lumbar interbody fusion (OLIF) approach increases the retroperitoneal oblique corridor (2020)

The retroperitoneal oblique corridors of L2 to L5 were significantly increased when the hip is in the neutral position, while the psoas cross-sectional area and anterior thickness were minimized in this position. Surgeons might benefit from a neutral position of the left hip in the oblique lateral lumbar interbody fusion (OLIF) procedure. In conclusion, the retroperitoneal oblique corridors of L2 to L5 were significantly increased when the hip is in the neutral position, while the psoas cross-sectional area and anterior thickness were minimized in this position. Surgeons might benefit from a neutral position of the left hip in the oblique lateral lumbar interbody fusion procedure.
On the Blistering of Al2O3 Passivation Layers for Si Solar Cells (2011)

Blister-free Al2O3-based surface passivation stacks for p-type Si passivated emitter and rear cells (PERCs) are developed. Measuring the blistering area and effective surface recombination velocity, it is shown that using (i) an Al2O3 layer ≤ 10 nm and (ii) out-gassing this Al2O3 film above 600 °C prior to capping is necessary. These blister-free Al2O3-based stacks are implemented as rear surface passivation for p-type Si PERC: 148.25 cm2 screen-printed cells with an average efficiency of 19.0 % have been made. There is an obvious gain in open circuit voltage of 5 mV compared to SiOx passivated PERC, thanks to enhanced rear surface passivation.
Single-Cell RNA Sequencing in Human Retinal Degeneration Reveals Distinct Glial Cell Populations (2020)

Degenerative diseases affecting retinal photoreceptor cells have numerous etiologies and clinical presentations. We clinically and molecularly studied the retina of a 70-year-old patient with retinal degeneration attributed to autoimmune retinopathy. The patient was followed for 19 years for progressive peripheral visual field loss and pigmentary changes. Single-cell RNA sequencing was performed on foveal and peripheral retina from this patient and four control patients, and cell-specific gene expression differences were identified between healthy and degenerating retina. Distinct populations of glial cells, including astrocytes and Müller cells, were identified in the tissue from the retinal degeneration patient. The glial cell populations demonstrated an expression profile consistent with reactive gliosis. This report provides evidence that glial cells have a distinct transcriptome in the setting of human retinal degeneration and represents a complementary clinical and molecular investigation of a case of progressive retinal disease.
Thermal Deoxygenation of syn‐15, 16‐Dioxo‐1,6 : 8,13‐bismethano[14]annulene to the Pyrene Isomer Dicyclohepta[cd,gh]pentalene (Azuleno[2,1,8‐ija]azulene) (1984)

A unique reaction takes place in the pyrolysis of the diketone 1. The formation of the pyrene isomer 2 (60%) can hardly be explained other than in terms of via a 1,2-dioxetane; thus, this reaction would be the reverse of the oxidative cleavage of electron-rich double bonds with singlet oxygen. In addition, 30% anthracene is obtained by the expected stepwise decomposition of 1 via a norcaradienone derivative.
Fuel wall film effects on premixed flame propagation, quenching and emission (2018)

The formation of fuel wall film is a primary cause for efficiency loss and emissions of unburnt hydrocarbons and particulate matters in direct injection engines, especially during cold start. When a premixed flame propagates toward a wall film of liquid fuel, flame structure and propagation could be fundamentally affected by the vaporization flux and the induced thermal and concentration stratifications. It is, therefore, of both fundamental and practical significance to investigate the consequent effect of a wall film on flame quenching. In this work, the interaction of a laminar premixed flame and a fuel wall film has been studied based on one-dimensional direct numerical simulation with detailed chemistry and transport. The mass and energy balance at the wall film interface have been implemented as boundary condition to resolve vaporization. Parametric studies are further conducted with various initial temperatures of 600–800 K, pressures of 7–15 atm, fuel film and wall temperatures of 300–400 K. By comparing the cases with an isothermal dry wall, it is found that the existence of a wall film always promotes flame quenching and causes more emissions. Although quenching distance can vary significantly among conditions, the local equivalence ratio at quenching is largely constant, suggesting the dominant effects of rich mixture and rich flammability limit. By further comparing constant volume and constant pressure conditions, it is observed that pressure and boiling point variation dominate the vaporization boundary layer development and flame quenching, which further suggests that increased pressure during compression stroke in engines can significantly suppress film vaporization. Emissions of unburnt hydrocarbon, soot precursor and low-temperature products before and after flame quenching are also investigated in detail. The results lead to useful insights on the interaction of flame propagation and wall film in well-controlled simplified configurations and shed light on the development of wall film models in three-dimensional in-cylinder combustion simulation.
Printed Graphene Electrochemical Biosensors Fabricated by Inkjet Maskless Lithography for Rapid and Sensitive Detection of Organophosphates (2018)

Solution phase printing of graphene-based electrodes has recently become an attractive low-cost, scalable manufacturing technique to create in-field electrochemical biosensors. Here, we report a graphene-based electrode developed via inkjet maskless lithography (IML) for the direct and rapid monitoring of triple-O linked phosphonate organophosphates (OPs); these constitute the active compounds found in chemical warfare agents and pesticides that exhibit acute toxicity as well as long-term pollution to soils and waterways. The IML-printed graphene electrode is nano/microstructured with a 1000 mW benchtop laser engraver and electrochemically deposited platinum nanoparticles (dia. ∼25 nm) to improve its electrical conductivity (sheet resistance decreased from ∼10 000 to 100 Ω/sq), surface area, and electroactive nature for subsequent enzyme functionalization and biosensing. The enzyme phosphotriesterase (PTE) was conjugated to the electrode surface via glutaraldehyde cross-linking. The resulting biosensor was able to rapidly measure (5 s response time) the insecticide paraoxon (a model OP) with a low detection limit (3 nM), and high sensitivity (370 nA/μM) with negligible interference from similar nerve agents. Moreover, the biosensor exhibited high reusability (average of 0.3% decrease in sensitivity per sensing event), stability (90% anodic current signal retention over 1000 s), longevity (70% retained sensitivity after 8 weeks), and the ability to selectively sense OP in actual soil and water samples. Hence, this work presents a scalable printed graphene manufacturing technique that can be used to create OP biosensors that are suitable for in-field applications as well as, more generally, for low-cost biosensor test strips that could be incorporated into wearable or disposable sensing paradigms.
First Principle Study of Electronic and Non-Linear Optical (NLO) Properties of Triphenylamine Dyes: Interactive Design Computation of New NLO Compounds (2015)

In this study, density functional theory and time-dependent density functional theory are used to determine how the size of p-conjugated system influences the absorption spectra and non-linear optical (NLO) properties of dyes. Double and triple bonds, as well the benzene rings, are used in conjugated systems. The results of the theoretical computation show that the absorption spectra are gradually broadened and red-shifted with increases in the conjugation length. Theoretical examination of the NLO properties was performed on the key parameters of polarizability and hyperpolarizability. A notable increase in the non-linear optical response was observed with an increase in the conjugation length of the p-spacer.
Haptic Interface on Measured Data for Epidural Simulation (2012)

This paper presents a haptic device with 3D computer graphics as part of a high fidelity medical epidural simulator development program. The haptic device is used as an input to move the needle in 3D, and also to generate force feedback to the user during insertion. A needle insertion trial was conducted on a porcine cadaver to obtain force data. The data generated from this trial was used to recreate the feeling of epidural insertion in the simulator. The interaction forces have been approximated to the resultant force obtained during the trial representing the force generated by the haptic device. The haptic device is interfaced with the 3D graphics for visualization. As the haptic stylus is moved, the needle moves on the screen and the depth of the needle tip indicates which tissue layer is being penetrated. Different forces are generated by the haptic device for each tissue layer as the epidural needle is inserted. As the needle enters the epidural space, the force drops to indicate loss of resistance.
Cell sorting by endocytotic capacity in a microfluidic magnetophoresis device (2011)

Magnetically labelled cells are finding a wealth of applications for in vitro analysis as well as in vivo treatments. Sorting of cells into subpopulations based on their magnetite loading is an important step in such procedures. Here, we study the sorting of monocytes and macrophages which internalise nanoparticles to different extents based on their endocytotic capacity. Macrophages featured a high endocytotic activity and were found to internalise between 4 and 60 pg of iron per cell. They were successfully sorted into five subpopulations of narrow iron loading distributions via on-chip free-flow magnetophoresis, thus demonstrating the potential of sorting of relatively similarly loaded cells. Monocytes featured a low endocytotic capacity and took on 1 to 4 pg of iron per cell. Mixtures of monocytes and macrophages were successfully sorted within the free-flow magnetophoresis chip and good purity (>88%), efficacy (>60%) and throughput (from 10 to 100 cells s(-1)) could be achieved. The introduced method constitutes a viable tool for studies of endocytotic capacity and sorting/selection of cells based on this functionality.
Modeling variable‐speed pump operations for target hydraulic characteristics (2009)

Conventional hydraulic models can be used to analyze operational scenarios for a variable‐speed pump (VSP) delivering target hydraulic characteristics of either the fixed hydraulic head or the desired pump flow. However, modelers must repeatedly adjust relative speed factors for achieving the target hydraulic performance, which can be a time‐consuming task. A new solution method has been developed for directly calculating the required VSP speed to provide a fixed hydraulic head. However, this method needs to be extended as a generic modeling approach for practical applications. This article presents an enhanced VSP solution method that extends the previously developed VSP hydraulic network solver to automatically calculate the relative pump‐speed coefficient for attaining the prescribed hydraulic head or pumping the preferred amount of flow. Using this improved method, engineers can model not only a single VSP but also multiple VSPs with rule‐based logic controls. This allows the target control head to be specified at any location or for the target flow to be specified for VSPs of different capacities. The extended method provides a flexible, robust modeling approach for engineers to analyze a variety of VSP configurations in water and wastewater collection systems.
Treatment of Genetic Diseases With CRISPR Genome Editing (2022)

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