gebhart/patrepeval huggingface dataset:
Automated scalable segmentation of neurons from multispectral images (2016)

Reconstruction of neuroanatomy is a fundamental problem in neuroscience. Stochastic expression of colors in individual cells is a promising tool, although its use in the nervous system has been limited due to various sources of variability in expression. Moreover, the intermingled anatomy of neuronal trees is challenging for existing segmentation algorithms. Here, we propose a method to automate the segmentation of neurons in such (potentially pseudo-colored) images. The method uses spatio-color relations between the voxels, generates supervoxels to reduce the problem size by four orders of magnitude before the final segmentation, and is parallelizable over the supervoxels. To quantify performance and gain insight, we generate simulated images, where the noise level and characteristics, the density of expression, and the number of fluorophore types are variable. We also present segmentations of real Brainbow images of the mouse hippocampus, which reveal many of the dendritic segments.
[Prehospital thrombolysis in the acute phase of myocardial infarction. Apropos of cases handled by the mobile intensive care unit,Argenteuil (Val-d'Oise) from 1988 to 1991]. (1993)

We have studied prehospital thrombolytic therapy in acute myocardial infarction administered by the mobile intensive care unit of the Argenteuil hospital (Val d'Oise), between 1988 and 1991, after having detailed the protocol used. Our results confirm the effectiveness of thrombolysis, showing a rapid improvement of pain and ST segment in 50% of cases. There is a significant saving of time between pain and thrombolysis when the treatment is started during the prehospital phase. At present, in accordance with Isis 3 study results, Streptokinase is the drug of choice with rtPA being reserved for cases with contraindications for Streptokinase.
Microwave-excited microplasma thruster: a numerical and experimental study of the plasma generation and micronozzle flow (2008)

A microplasma thruster of the electrothermal type has been developed using azimuthally symmetric microwave-excited microplasmas. The plasma source was ∼2 mm in diameter and ∼10 mm long, and operated at around atmospheric pressures; the micronozzle was a converging–diverging type, having a throat ∼0.2 mm in diameter and ∼1 mm long. Numerical and experimental results with Ar demonstrated that this miniature electrothermal thruster gives a thrust of >1 mN, a specific impulse of ∼100 s and a thrust efficiency of ∼10% at a microwave power of <10 W.
Effect of Surface Roughness on Adhesion and Friction of Microfibers in Side Contact (2008)

A multi-scale mathematical model is used to study the effect of surface roughness on the adhesion and friction of microfibers engaged in side contact. Results are compared to closed-form analytic approximations derived from linear elastic contact mechanics.
Transcriptome analysis reveals a comprehensive insect resistance response mechanism in cotton to infestation by the phloem feeding insect Bemisia tabaci (whitefly) (2016)

The whitefly (Bemisia tabaci) causes tremendous damage to cotton production worldwide. However, very limited information is available about how plants perceive and defend themselves from this destructive pest. In this study, the transcriptomic differences between two cotton cultivars that exhibit either strong resistance (HR) or sensitivity (ZS) to whitefly were compared at different time points (0, 12, 24 and 48 h after infection) using RNA-Seq. Approximately one billion paired-end reads were obtained by Illumina sequencing technology. Gene ontology and KEGG pathway analysis indicated that the cotton transcriptional response to whitefly infestation involves genes encoding protein kinases, transcription factors, metabolite synthesis, and phytohormone signalling. Furthermore, a weighted gene co-expression network constructed from RNA-Seq datasets showed that WRKY40 and copper transport protein are hub genes that may regulate cotton defenses to whitefly infestation. Silencing GhMPK3 by virus-induced gene silencing (VIGS) resulted in suppression of the MPK-WRKY-JA and ET pathways and lead to enhanced whitefly susceptibility, suggesting that the candidate insect resistant genes identified in this RNA-Seq analysis are credible and offer significant utility. Taken together, this study provides comprehensive insights into the cotton defense system to whitefly infestation and has identified several candidate genes for control of phloem-feeding pests.
Collision energy dependence of the HD(ν′=2) product rotational distribution of the H+D2 reaction in the range 1.30–1.89 eV (2004)

An experimental and theoretical investigation of the collision energy dependence of the HD(nu' = 2,j') rotational product state distribution for the H + D2 reaction in the collision energy range of Ecol = 1.30-1.89 eV has been carried out. Theoretical results based on time-dependent and time-independent quantum mechanical methods agree nearly perfectly with each other, and the agreement with the experiment is good at low collision energies and very good at high collision energies. This behavior is in marked contrast to a previous report on the HD(nu' = 3,j') product state rotational distribution [Pomerantz et al., J. Chem. Phys. 120, 3244 (2004)] where a systematic difference between experiment and theory was observed, especially at the highest collision energies. The reason for this different behavior is not yet understood. In addition, this study employs Doppler-free spectroscopy to resolve an ambiguity in the E, F-X resonantly enhanced multiphoton ionization transition originating from the HD(nu' = 2,j' = 1) state, which is found to be caused by an accidental blending with the transition coming from the HD(nu' = 1,j' = 14) state.
ABY 3 (2018)

Machine learning is widely used to produce models for a range of applications and is increasingly offered as a service by major technology companies. However, the required massive data collection raises privacy concerns during both training and prediction stages. In this paper, we design and implement a general framework for privacy-preserving machine learning and use it to obtain new solutions for training linear regression, logistic regression and neural network models. Our protocols are in a three-server model wherein data owners secret share their data among three servers who train and evaluate models on the joint data using three-party computation (3PC). Our main contribution is a new and complete framework ($\textABY ^3$) for efficiently switching back and forth between arithmetic, binary, and Yao 3PC which is of independent interest. Many of the conversions are based on new techniques that are designed and optimized for the first time in this paper. We also propose new techniques for fixed-point multiplication of shared decimal values that extends beyond the three-party case, and customized protocols for evaluating piecewise polynomial functions. We design variants of each building block that is secure against \em malicious adversaries who deviate arbitrarily. We implement our system in C++. Our protocols are up to \em four orders of magnitude faster than the best prior work, hence significantly reducing the gap between privacy-preserving and plaintext training.
Experimental demonstration of a distributed antenna array pre-synchronized for retrodirective transmission (2016)

We describe the key ideas behind our implementation of a distributed antenna array fully pre-synchronized for retrodirective transmission to an external receiver. In our implementation, a number of wireless transceivers in a network use a sequence of simple in-band wireless message exchanges to calibrate themselves so that these transceivers can obtain their channel gains to an external receiver using reciprocity simply by observing a single incoming transmission from that receiver without any channel feedback or other cooperation from the receiver. Some notable features of our implementation are as follows: (a) it automatically calibrates and corrects for unknown channel gains, oscillator offsets and drifts between the array nodes as well as the effect of non-reciprocal RF hardware; (b) it is fully wireless and endogenous i.e., does not use any wired backhaul connections or side channels including GPS; and (c) it uses simple signal processing on a standard and widely available software-defined radio platform based on off-the-shelf hardware and open-source software. Also, to the best of our knowledge, this is the first ever demonstration of a pre-synchronized distributed array, and thus our implementation serves as a proof-of-concept and allows for the development of more advanced distributed array techniques building on this capability.
Precoder Design With Incomplete Feedback for Joint Transmission (2015)

A centralized coordinated multipoint downlink joint transmission in a frequency division duplex system requires channel state information (CSI) to be fed back from the cell-edge users to their serving BS, and aggregated at the central coordination node for precoding, so that interference can be mitigated. The control signals comprising of CSI and the precoding weights can easily overwhelm the backhaul resources. Relative thresholding has been proposed to alleviate the burden; however, this is at the cost of reduction in throughput. In this paper, we propose utilizing the long-term channel statistics comprising of pathloss and shadow fading in the precoder design to model the statistical interference for the unknown CSI. In this regard, a successive second-order cone programming (SSOCP)-based precoder for maximizing the weighted sum rate is proposed. The accuracy of the solution obtained is bounded with the branch and bound technique. An alternative optimization framework via weighted mean square error minimization is also derived. Both these approaches provide an efficient solution close to the optimal, and also achieve efficient backhauling, in a sense that the precoding weights are generated only for the active links. For comparison, a stochastic approach based on particle swarm optimization is also considered.
Fe–N–C Boosts the Stability of Supported Platinum Nanoparticles for Fuel Cells (2022)

The poor durability of Pt-based nanoparticles dispersed on carbon black is the challenge for the application of long-life polymer electrolyte fuel cells. Recent work suggests that Fe- and N-codoped carbon (Fe-N-C) might be a better support than conventional high-surface-area carbon. In this work, we find that the electrochemical surface area retention of Pt/Fe-N-C is much better than that of commercial Pt/C during potential cycling in both acidic and basic media. <i>In situ</i> inductively coupled plasma mass spectrometry studies indicate that the Pt dissolution rate of Pt/Fe-N-C is 3 times smaller than that of Pt/C during cycling. Density functional theory calculations further illustrate that the Fe-N-C substrate can provide strong and stable support to the Pt nanoparticles and alleviate the oxide formation by adjusting the electronic structure. The strong metal-substrate interaction, together with a lower metal dissolution rate and highly stable support, may be the reason for the significantly enhanced stability of Pt/Fe-N-C. This finding highlights the importance of carbon support selection to achieve a more durable Pt-based electrocatalyst for fuel cells.
Additive manufacture of complex 3D Au-containing nanocomposites by simultaneous two-photon polymerisation and photoreduction (2017)

The fabrication of complex three-dimensional gold-containing nanocomposite structures by simultaneous two-photon polymerisation and photoreduction is demonstrated. Increased salt delivers reduced feature sizes down to line widths as small as 78 nm, a level of structural intricacy that represents a significant advance in fabrication complexity. The development of a general methodology to efficiently mix pentaerythritol triacrylate (PETA) with gold chloride hydrate (HAuCl<sub>4</sub>∙3H<sub>2</sub>O) is reported, where the gold salt concentration is adjustable on demand from zero to 20 wt%. For the first-time 7-Diethylamino-3-thenoylcoumarin (DETC) is used as the photoinitiator. Only 0.5 wt% of DETC was required to promote both polymerisation and photoreduction of up to 20 wt% of gold salt. This efficiency is the highest reported for Au-containing composite fabrication by two-photon lithography. Transmission Electron Microscopy (TEM) analysis confirmed the presence of small metallic nanoparticles (5.4 ± 1.4 nm for long axis / 3.7 ± 0.9 nm for short axis) embedded within the polymer matrix, whilst X-ray Photoelectron Spectroscopy (XPS) confirmed that they exist in the zero valent oxidation state. UV-vis spectroscopy defined that they exhibit the property of localised surface plasmon resonance (LSPR). The capability demonstrated in this study opens up new avenues for a range of applications, including plasmonics, metamaterials, flexible electronics and biosensors.
Gas phase synthesis of non-bundled, small diameter single-walled carbon nanotubes with near-armchair chiralities (2015)

We present a floating catalyst synthesis route for individual, i.e., non-bundled, small diameter single-walled carbon nanotubes (SWCNTs) with a narrow chiral angle distribution peaking at high chiralities near the armchair species. An ex situ spark discharge generator was used to form iron particles with geometric number mean diameters of 3–4 nm and fed into a laminar flow chemical vapour deposition reactor for the continuous synthesis of long and high-quality SWCNTs from ambient pressure carbon monoxide. The intensity ratio of G/D peaks in Raman spectra up to 48 and mean tube lengths up to 4 μm were observed. The chiral distributions, as directly determined by electron diffraction in the transmission electron microscope, clustered around the (n,m) indices (7,6), (8,6), (8,7), and (9,6), with up to 70% of tubes having chiral angles over 20°. The mean diameter of SWCNTs was reduced from 1.10 to 1.04 nm by decreasing the growth temperature from 880 to 750 °C, which simultaneously increased the fraction of semiconducting tubes from 67% to 80%. Limiting the nanotube gas phase number concentration to ∼105 cm−3 prevented nanotube bundle formation that is due to collisions induced by Brownian diffusion. Up to 80% of 500 as-deposited tubes observed by atomic force and transmission electron microscopy were individual. Transparent conducting films deposited from these SWCNTs exhibited record low sheet resistances of 63 Ω/□ at 90% transparency for 550 nm light.
Variability of glenohumeral positioning and bone-to-tendon marker length measurements in repaired rotator cuffs from longitudinal computed tomographic imaging (2020)

Apparent tendon retraction of 5 mm or more, when measured as the distance from a tendon marker's day of surgery location to its new location on a volumetrically registered longitudinal CT scan, may be considered above the usual range of measurement variation. Tendon retraction measured using implanted radiopaque tendon markers offers an objective and sufficiently reliable means for quantifying the commonly expected changes in structural healing following rotator cuff repair.
Hydrogen and Oxygen Evolution on Boron‐Doped Diamond Electrodes (1996)

The evolution of hydrogen and oxygen was studied on diamond electrodes containing approximately 1021 boron atom/cm3. Voltammetry showed a wide potential window [−1.25 to +2.3 V vs. standard hydrogen electrode (SHE)] without significant water decomposition. This window was much narrower for poor quality diamond films with appreciable sp2 content. A redox couple observed at +1.7 V indicates oxidation of the diamond surface prior to oxygen evolution. The extent of surface oxidation increased with sp2 content. Anodic polarization made the diamond surface hydrophilic; x‐ray photoelectron spectroscopy showed an increase in oxygen coverage and the presence of carbon‐oxygen bonds. The estimated capacitance of the interface ranged from 0.05 μF/cm2 for high quality diamond to 5 μF/cm2 for low quality diamond. Preliminary measurements of the exchange current densities for oxygen and hydrogen evolution indicated slow kinetics compared to metals or highly oriented pyrolytic graphite.
Helminth egg derivatives as pro-regenerative immunotherapies (2022)

Abstract The immune system is increasingly recognized as an important regulator of tissue repair. We developed a regenerative immunotherapy from the helminth Schistosoma mansoni soluble egg antigen (SEA) to stimulate production of interleukin (IL)-4 and other type 2-associated cytokines without negative infection-related sequelae. The regenerative SEA (rSEA) applied to a murine muscle injury induced accumulation of IL-4 expressing T helper cells, eosinophils, and regulatory T cells, and decreased expression of IL-17A in gamma delta (γδ) T cells, resulting in improved repair and decreased fibrosis. Encapsulation and controlled release of rSEA in a hydrogel further enhanced type 2 immunity and larger volumes of tissue repair. The broad regenerative capacity of rSEA was validated in articular joint and corneal injury models. These results introduce a new regenerative immunotherapy approach using natural helminth-derivatives. One-Sentence Summary Helminth-derived soluble egg antigen regenerative immunotherapies promote tissue repair in multiple injury models.
Modeling of Negative Streamer Propagation in a Weak Uniform Electric Field (2003)

The results of numerical simulations of negative streamers in air at atmospheric pressure in a weak and uniform electric field are presented. Streamer development was considered between a protrusion on a plane cathode and a plane anode separated by a distance of 3.3 cm. The region with an enhanced field near the protrusion tip, where streamer inception took place, was ~0.3 cm long and the propagation region with a uniform background field covered ~3 cm of the gap length. The parameters of the streamers were studied for different magnitudes of the background field strength: 5, 6, 7 and 8 kV/cm at constant magnitude of the field strength at the tip of the protrusion aiming to determine minimal field required for stable propagation. Internal and integral characteristics of streamers developing in different background fields are discussed and analyzed. 1.
ICF target diagnostics on PBFA II (invited) (1992)

Particle Beam Fusion Accelerator II is a light-ion fusion accelerator that is presently capable of irradiating a 6-mm-diam sphere with ∼50 kJ of 5.5-MeV protons in ∼15 ns. An array of particle and x-ray diagnostics fielded on proton Inertial Confinement Fusion target experiments quantifies the incident particle beam and the subsequent target response. An overview of the ion and target diagnostic setup and capabilities will be given in the context of recent proton beam experiments aimed at studying soft x-ray emission from foam-filled targets and the hydrodynamic response of exploding-pusher targets. Ion beam diagnostics indicate ∼100 kJ of proton beam energy incident within a 1.2-cm radius of the center of the diode with an azimuthal uniformity which varied between 6% and 29%. Foam-filled target temperatures of 35 eV and closure velocities of 4 cm/μs were measured.
Carbon Dioxide Separation with Supported Ionic Liquid Membranes (2007)

A practical form of CO2 capture at water-gas shift conditions in the IGCC process could serve the dual function of producing a pure CO2 stream for sequestration and forcing the equilibrium-limited shift reaction to completion enriching the stream in H2. The shift temperatures, ranging from the low temperature shift condition of 260°C to the gasification condition of 900°C, limit capture options by diminishing associative interactions which favor removal of CO2 from the gas stream. Certain sorption interactions, such as carbonate formation, remain available but generally involve exceptionally high sorbent regeneration energies that contribute heavily to parasitic power losses. Carbon dioxide selective membranes need only establish an equilibrium between the gas phase and sorption states in order to transport CO2, giving them a potential energetic advantage over other technologies. Supported liquid membranes take advantage of high, liquid phase diffusivities and a solution diffusion mechanism similar to that observed in polymeric membranes to achieve superior permeabilities and selectivites. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high CO2 solubility relative to light gases such as H2, are excellent candidates for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of ionic liquids including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide in supported ionic liquid membranes for the capture of CO2 from streams containing H2. In a joint project, researchers at the University of Notre Dame synthesized and characterized ionic liquids, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Improvements to the ionic liquid and support have allowed testing of these supported ionic liquid membranes at temperatures up to 300°C without loss of support mechanical stability or degradation of the ionic liquid. Substantial improvements in selectivity have also been observed at elevated temperature with the best membrane currently achieving optimum performance at 75°C.
On-Policy Reinforcement Learning via Ensemble Gaussian Processes with Application to Resource Allocation (2021)

Reinforcement learning (RL) is an interactive decisionmaking tool with well documented merits for resource allocation tasks in uncertain environments, such as those emerging with Internet-of-Things. While they can attain state-of-the-art performance in several application domains, RL using deep neural networks can be less attractive when the training datasets involved are prohibitively large. Aiming at sample efficiency, this contribution adopts nonparametric value function models using Gaussian processes (GPs). Relying on the temporal-difference update rule, a novel GP-SARSA approach is developed, where the action selection is guided by Thompson sampling to balance exploration and exploitation. Targeting also computational scalability, the advocated approach leverages random features that replace GP-SARSA's nonparametric function learning with a parametric approximate model. Adaptation to unknown dynamics is accomplished through an ensemble (E) of GP-SARSA learners, whose weights are updated in a data-driven fashion. Performance of the proposed (E)GP-SARSA is evaluated on a practical resource allocation problem.
Influence of the Surfactant Concentration on Miniemulsion Polymerization for the Preparation of Hybrid Nanoparticles (2012)

Abstract The surfactant concentration in miniemulsion polymerization is a very important parameter. At surfactant concentrations lower than a critical value, coalescence of monomer droplets changes their size, whereas concentrations too high lead to the formation of micelles and micellar nucleation in the polymerization step. Inorganic particles dispersed in the monomer phase, with the goal to produce hybrid particles, influence the surfactant concentration needed as shown in this contribution. Values for the ideal surfactant concentration have been determined for different combinations of particles and surfactant. Underlying mechanisms for the required adjustment of surfactant concentration are discussed.