gebhart/patrepeval huggingface dataset:
Hybrid Metal-Graphene Plasmons for Tunable Terahertz Optoelectronics (2015)

Among its many outstanding properties, graphene supports terahertz surface plasma waves -- sub-wavelength charge density oscillations connected with electromagnetic fields that are tightly localized near the surface[1,2]. When these waves are confined to finite-sized graphene, plasmon resonances emerge that are characterized by alternating charge accumulation at the opposing edges of the graphene. The resonant frequency of such a structure depends on both the size and the surface charge density, and can be electrically tuned throughout the terahertz range by applying a gate voltage[3,4]. The promise of tunable graphene THz plasmonics has yet to be fulfilled, however, because most proposed optoelectronic devices including detectors, filters, and modulators[5-10] desire near total modulation of the absorption or transmission, and require electrical contacts to the graphene -- constraints that are difficult to meet using existing plasmonic structures. We report here a new class of plasmon resonance that occurs in a hybrid graphene-metal structure. The sub-wavelength metal contacts form a capacitive grid for accumulating charge, while the narrow interleaved graphene channels, to first order, serves as a tunable inductive medium, thereby forming a structure that is resonantly-matched to an incident terahertz wave. We experimentally demonstrate resonant absorption near the theoretical maximum in readily-available, large-area graphene, ideal for THz detectors and tunable absorbers. We further predict that the use of high mobility graphene will allow resonant THz transmission near 100%, realizing a tunable THz filter or modulator. The structure is strongly coupled to incident THz radiation, and solves a fundamental problem of how to incorporate a tunable plasmonic channel into a device with electrical contacts.
MIXED VALENCE COPPER OXIDES: RELATIONSHIPS BETWEEN CRYSTAL CHEMISTRY AND SUPERCONDUCTIVITY (1988)

The influence of different factors — mixed valence of copper, coordination of this element, low dimensionality of the structure, phase transition and non-stoichiometry — upon superconductivity is analyzed for the two families of higher T c superconductors La 2 CuO 4 and YBa 2 Cu 3 O 7 -type.
Quest for Controlled Combustion Engines (1988)

<div class="htmlview paragraph">Upon ‘harnessing the fire’ by the early pioneers, the quest for controlled combustion provided the major incentive for progress in engine technology. At first this involved primarily the problem of knock and later that of pollutant emissions. It appears that both can be solved by treating the engine cylinder not only as a source of power but also as a controllable chemical reactor. The principal concept whereby this can be accomplished involves multi-point ignition combined with charge dilution and stratification. Means for this purpose include jet ignition, product recirculation, and chemical additives. The most suitable for the realization of this concept is a direct injection two-stroke engine.</div>
Fast tunable laser based on Fabry-Perot lasers with optical injection (2004)

We have proposed and experimentally demonstrated a new tunable laser structure, which is based on Fabry-Perot (FP) lasers with external lightwave injection. The wavelength tuning can be obtained by adjusting the bias currents of FP lasers. The wavelength tuning time of <2 ns, 3.3-nm tuning range, and the side-mode suppression ratio (SMSR) of >19 dB have been achieved experimentally. In addition, the SMSR performance has also been investigated. This tunable laser has the advantage of simple architecture, potentially low cost, data direct modulation, and fast wavelength tuning, and is expected to benefit the applications of fast wavelength tuning.
Abstract WP107: Optogenetic Stimulation of Human Neural Stem Cell Grafts In Ischemic Brain (2013)

Optogenetically engineered neural stem cells (NSCs) provide a targeted approach to probe the role of neural circuits NSC-based cell therapy in experimental stroke models. A large body of work provides evidence that the therapeutic benefits of NSC grafts are mediated by replacement of cells lost to injury or disease and by secretion of neurotrophic and regenerative factors. Currently the potential of the grafted cells to modulate local circuits and to modify motor performances in animal model of ischemic brain injury is not well understood. This study explores whether optogenetic stimulation of NSC grafts will modulate neural differentiation and integration into the local circuitry. We isolated multipotent NSCs from human embryonic stem cells. The NSCs were transduced with lentiviral vectors carrying the channelrodopsin-2 (ChR2) gene fused with enhanced yellow fluorescent protein (ChR2-EYFP) under the EF1alpha promoter. The ChR2 expression and response of the NSC progeny to blue light stimulation (470 nm) was confirmed in vitro. To test the function of these cells in stroke model, Sprague Dawley rats were subjected to middle cerebral artery occlusion (65 minutes). One week later, immunosuppressed rats received transplantation of NSCs (2 x 105) into the ischemic boundary zone in the striatum. Chronic optogenetic stimulation of the grafted cells was carried out daily after transplantation for 1 month. Five animal groups were established: vehicle, vehicle with stimulation, NSC transplant with chronic stimulation, NSC transplant without chronic stimulation and NSC with control (non-ChR2) vector. Animals in all groups were tested weekly for their motor performance through testing spontaneous forelimb use during lateral exploratory movement and the vibrissae-elicited forelimb-placing test. Preliminary results suggest that animals that received chronic stimulation showed an enhanced sensorimotor performance in comparison to animals that did not receive stimulation. The effects of long-term optogenetically-controlled stimulation of the grafted cells on the cellular differentiation and functional recovery in animals with ischemic brain injury will be presented.
Automatic detection of plagiarized spoken responses (2014)

This paper addresses the task of automatically detecting plagiarized responses in the context of a test of spoken English proficiency for non-native speakers. A corpus of spoken responses containing plagiarized content was collected from a high-stakes assessment of English proficiency for non-native speakers, and several text-to-text similarity metrics were implemented to compare these responses to a set of materials that were identified as likely sources for the plagiarized content. Finally, a classifier was trained using these similarity metrics to predict whether a given spoken response is plagiarized or not. The classifier was evaluated on a data set containing the responses with plagiarized content and non-plagiarized control responses and achieved accuracies of 92.0% using transcriptions and 87.1% using ASR output (with a baseline accuracy of 50.0%).
Vector Quantization of Channel Information in Linear Multi-User MIMO Systems (2006)

In this paper, we propose a new vector quantization (VQ) algorithm for encoding channel state information feedback in multiple antenna, multi-user systems operating on flat fading channels with rich scattering. We consider an approach where the receiver chooses an instantaneous throughput maximizing modulation matrix from a finite set of predefined matrices (codewords). The codebook of modulation matrices is constructed based on joint optimization of the dominant channel eigenmodes of users and separate quantization of power levels. The proposed algorithm is very flexible and can be used in a variety of system configurations, including varying number of receiver antennas and frequency selective channels. We implement the proposed algorithm on flat fading MIMO channels and show the influence of the feedback rate on system capacity. We demonstrate that, even with low feedback rate, the ergodic capacity of the proposed system closely approaches the theoretic capacity of the system with perfect channel state information at the transmitter.
High-sensitivity scatterometer with a bidirectional ring laser (2003)

We present a technique for the absolute measurement of very low-level scattering. The method is absolute in that it relies on fundamental physics and does not require calibration against standards maintained by the National Institute of Standards. In a bi-directional mode-locked ring laser, a difference in longitudinal mode frequency between the two senses of circulation of the intracavity pulses can be measured as a beat note between the corresponding outputs. A very small amount of light backscattered by a sample (located at the pulse crossing) from one sense of circulation into the other, causes the beat note to vanish. The threshold in mode frequency difference that causes locking is a measure of the scattering amplitude.
Prevention of early renal disease, dyslipidaemia and lipid peroxidation in STZ-diabetic rats by LR-9 and LR-74, novel AGE inhibitors (2005)

Both compounds can inhibit the progression of renal disease and also prevent dyslipidaemia in type-1 diabetic animals. These compounds may have an additional beneficial effect as an antioxidant against lipid peroxidation, and thus may provide alternative therapeutic options for the treatment of various diabetic macrovascular complications.
Strong Higher-Order Fiber Bragg Gratings Written with an Amplitude Mask (1997)

Reflective Bragg gratings have been written in optical fibers using UV induced index changes. Initial work used a standing wave interference pattern set up by light launched down the fiber core. 1 The more versatile techniques of side-writing using bulk interferometric fringes 2 and phase-masks 3 followed. The field of phase-mask-written Bragg gratings in germano-silicate fibers has matured with the use of specially designed high-photosensitivity fiber and hydrogen loading. 4 While gratings written with these methods can be precisely tailored in spectral shape, bandwidth and strength, a precise mask, a coherent laser, and very stable alignment during the exposure are needed. Multiple grating applications, including weak pump-diode stabilizers, fiber laser mirrors, and grating sensors may not require the high precision gratings produced with the phase mask method, but would benefit from an inexpensive mass production technique. In this paper we demonstrate an amplitude mask exposure technique to create strong higher order Bragg reflectors with minimal optics.
Deactivation of Z-selective olefin metathesis catalyst via 1,2-sulfide shift (2018)

Since the advent of olefin metathesis, stereoselective olefin metathesis catalysts have been sought after for use in academic and industrial applications. The most recently reported Ru-complex for Z-selective olefin metathesis features a catechothiolate ligand, and this catalyst has been shown to be esp. useful in ring-opening metathesis polymn. and ringopening-cross metathesis. However, this catalyst is prone to deactivation, as the electron-rich sulfur in the catechodithiolate ligand is susceptible to undergo a 1,2-shift to the neighboring electrophilic alkylidene, which effectively deactivates the catalyst. Hoveyda et al. used electroneg. groups on the dithiolate ligand to diminish the rate of the proposed isomerization and thus favor olefin metathesis towards high-value Z-allylic alc. products. However, a deeper\nstudy of the mechanism of deactivation and a further anal. of the electronic structure is necessary in order to understand the deactivation pathway and tune the catalyst to disfavor this 1,2-shift. Guided by expts., we present a computational study of the reaction pathway and present results on the electronic nature of the catalytically active species. We study the propensity for the catalytic species to undergo deactivation by analyzing the altered electronic structure that results from substrate coordination and alkylidene substitution. This work serves as grounds for understanding the reactivity of this new class of Ru-complexes and we propose design principles for further development of these catalysts for academic and industrial use.
Enduring toxicity of transgenic <i>Anabaena</i> PCC 7120 expressing mosquito larvicidal genes from <i>Bacillus thuringiensis</i> ssp. <i>israelensis</i> <sup>†</sup> (2003)

Persistence of biological control agents against mosquito larvae was tested under simulated field conditions. Mosquito larvicidal activity of transgenic Anabaena PCC 7120 expressing cry4Aa, cry11Aa and p20 from Bacillus thuringiensis ssp. israelensis was greater than B. thuringiensis ssp. israelensis primary powder (fun 89C06D) or wettable powder (WP) (Bactimos products) when either mixed with silt or exposed to sunlight outdoors. Reduction of Bactimos primary powder toxicity was at least 10-fold higher than Anabaena's after mixing with silt. In outdoors experiments, Bactimos WP remained toxic (over 30% mortality of 3rd instar Aedes aegypti larvae) for 2-4 days only, while transgenic Anabaena's toxicity endured 8-21 days.
Dual targeting of salt inducible kinases and CSF1R uncouples bone formation and bone resorption (2021)

Abstract Bone formation and resorption are typically coupled, such that the efficacy of anabolic osteoporosis treatments may be limited by bone destruction. The multi-kinase inhibitor YKL-05-099 potently inhibits salt inducible kinases (SIKs) and may represent a promising new class of bone anabolic agents. Here we report that YKL-05-099 increases bone formation in hypogonadal female mice without increasing bone resorption. Postnatal mice with inducible, global deletion of SIK2 and SIK3 show increased bone mass, increased bone formation, and, distinct from the effects of YKL-05-099, increased bone resorption. No cell-intrinsic role of SIKs in osteoclasts was noted. In addition to blocking SIKs, YKL-05-099 also binds and inhibits CSF1R, the receptor for the osteoclastogenic cytokine M-CSF. Modeling reveals that YKL-05-099 binds to SIK2 and CSF1R in a similar manner. Dual targeting of SIK2/3 and CSF1R induces bone formation without concomitantly increasing bone resorption and thereby may overcome limitations of most current anabolic osteoporosis therapies.
Detection and Rectification of Distorted Fingerprints (2015)

Elastic distortion of fingerprints is one of the major causes for false non-match. While this problem affects all fingerprint recognition applications, it is especially dangerous in negative recognition applications, such as watchlist and deduplication applications. In such applications, malicious users may purposely distort their fingerprints to evade identification. In this paper, we proposed novel algorithms to detect and rectify skin distortion based on a single fingerprint image. Distortion detection is viewed as a two-class classification problem, for which the registered ridge orientation map and period map of a fingerprint are used as the feature vector and a SVM classifier is trained to perform the classification task. Distortion rectification (or equivalently distortion field estimation) is viewed as a regression problem, where the input is a distorted fingerprint and the output is the distortion field. To solve this problem, a database (called reference database) of various distorted reference fingerprints and corresponding distortion fields is built in the offline stage, and then in the online stage, the nearest neighbor of the input fingerprint is found in the reference database and the corresponding distortion field is used to transform the input fingerprint into a normal one. Promising results have been obtained on three databases containing many distorted fingerprints, namely FVC2004 DB1, Tsinghua Distorted Fingerprint database, and the NIST SD27 latent fingerprint database.
The Uranium from Seawater Program at the Pacific Northwest National Laboratory: Overview of Marine Testing, Adsorbent Characterization, Adsorbent Durability, Adsorbent Toxicity, and Deployment Studies (2016)

The Pacific Northwest National Laboratory (PNNL) is evaluating the performance of adsorption materials to extract uranium from natural seawater. Testing consists of measurements of the adsorption of uranium and other elements from seawater as a function of time using flow-through columns and a recirculating flume to determine adsorbent capacity and adsorption kinetics. The amidoxime-based polymer adsorbent AF1, produced by Oak Ridge National Laboratory (ORNL), had a 56-day adsorption capacity of 3.9 ± 0.2 g U/kg adsorbent material, a saturation capacity of 5.4 ± 0.2 g U/kg adsorbent material, and a half-saturation time of 23 ± 2 days. The ORNL AF1 adsorbent has a very high affinity for uranium, as evidenced by a 56-day distribution coefficient between adsorbent and solution of log KD,56day = 6.08. Calcium and magnesium account for a majority of the cations adsorbed by the ORNL amidoxime-based adsorbents (61% by mass and 74% by molar percent), uranium is the fourth most abundant element adsorbed by mass and seventh most abundant by molar percentage. Marine testing at Woods Hole Oceanographic Institution with the ORNL AF1 adsorbent produced adsorption capacities 15% and 55% higher than those observed at PNNL for column and flume testing, respectively. Variations in competing ions may be the explanation for the regional differences. Hydrodynamic modeling predicts that a farm of adsorbent materials will likely have minimal effect on ocean currents and removal of uranium and other elements from seawater when farm densities are <1800 braids/km2. A decrease in uranium adsorption capacity of up to 30% was observed after 42 days of exposure because of biofouling when the ORNL braided adsorbent AI8 was exposed to raw seawater in a flume in the presence of light. No toxicity was observed with flow-through column effluents of any absorbent materials tested to date. Toxicity could be induced with some non-amidoxime based absorbents only when the ratio of solid absorbent to test media was increased to part per thousand levels. Thermodynamic modeling of the seawater−amidoxime adsorbent was performed using the geochemical modeling program PHREEQC. Modeling of the binding of Ca, Mg, Fe, Ni, Cu, U, and V reveal that when binding sites are limited (1 × 10–8 binding sites/kg seawater), vanadium heavily outcompetes other ions for the amidoxime sites. In contrast, when binding sites are abundant, Mg and Ca dominate the total percentage of metals bound to the sorbent.
A <sup>3</sup>He<sup>++</sup> Radio-Frequency Quadrupole Accelerator for Positron Emission Tomography (1990)

The feasibility of using a radio-frequency quadrupole (RFQ) accelerator to accelerate 3He++for use in positron emission tomography (PET) is shown. The 3He++ RFQ is extremely lightweight in comparison to a cyclotron, but can nevertheless produce all four radioisotopes of interest (18F, 13N, 15O, and 11C) in more than adequate quantities. Due to the neutron-poor nature of 3He++, the desired positron emitters can be produced from naturally abundant target isotopes. In addition, target reactions and collisions with the accelerating structure produce relatively small numbers of neutrons compared to proton and deuteron systems. This yields two economic advantages. Enriched 13C, 15N, and 18O target materials are not required. Also, the shielding requirements are reduced considerably, and there is no need for radiation shielding around the accelerator. This reduced shielding results in a factor of 8 reduction in total facility shielding weight compared to a proton/deuteron cyclotron facility. The order of magnitude reduction in facility weight, the virtual elimination of the accelerator weight, and the relative lack of residual induced activity gives rise to the possibility of a radiopharmaceutical production system that is less expensive than present systems and may ultimately be transportable. Such a system could make PET imaging technology far more accessible geographically and financially than it is at present.
Nlog N dual shuffle-exchange network with error-correcting routing (1994)

Describes a dual shuffle-exchange switching network (DSN) that makes use of the principle of error-correcting routing. For motivation, parallels are drawn between error-correcting routing in switching and error-correcting coding in transmission. Based on a novel error-correcting and self-routing algorithm, the authors show by analysis and simulation that the DSN can achieve the Shannon's lower bound Nlog N on switch complexity while satisfying four desirable criteria: 1) self-routing property; 2) no queueing of packets at the inputs or inside the switch; 3) arbitrarily small packet-loss probability; 4) close-to-100% throughput. Different implementations of the basic DSN concept and their trade-offs are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A time-varying subjective quality model for mobile streaming videos with stalling events (2015)

Over-the-top mobile video streaming is invariably influenced by volatile network conditions which cause playback interruptions (stalling events), thereby impairing users' quality of experience (QoE). Developing models that can accurately predict users' QoE could enable the more efficient design of quality-control protocols for video streaming networks that reduce network operational costs while still delivering high-quality video content to the customers. Existing objective models that predict QoE are based on global video features, such as the number of stall events and their lengths, and are trained and validated on a small pool of <i>ad hoc </i>video datasets, most of which are not publicly available. The model we propose in this work goes beyond previous models as it also accounts for the fundamental effect that a viewer's recent level of satisfaction or dissatisfaction has on their overall viewing experience. In other words, the proposed model accounts for and adapts to the recency, or hysteresis effect caused by a stall event in addition to accounting for the lengths, frequency of occurrence, and the positions of stall events - factors that interact in a complex way to affect a user's QoE. On the recently introduced LIVE-Avvasi Mobile Video Database, which consists of 180 distorted videos of varied content that are afflicted solely with over 25 unique realistic stalling events, we trained and validated our model to accurately predict the QoE, attaining standout QoE prediction performance.
Gradientless Propulsion and State Switching of Bubble Domains (1976)

We investigate a class of phenomena which we call bubble automotion whereby a bubble or a bubble lattice is propelled by a time‐modulated field which is homogeneous rather than by locally applied field gradients. Linear translation of certain kinds of bubbles occurs when bias modulation Hb+hz(t) having certain amplitudes and large ∣dhz/dt∣ is superimposed on a steady in‐plane field Hip which is less than Hb. Pulsed hz excitations produce characteristic automotion vectors that can uniquely distinguish for the first time among certain wall states (S,L,P) having a common winding number S but different arrangements of L Bloch lines and P Bloch points. A pair of S=1 bubbles we call σ+ and σ−, translate typically one micron per pulse in opposite directions orthogonal to Hip, i.e., parallel to ±Hb⇒ × Hip⇒. A model consistent with our measurements has the static configurations (1,2,0)+ and (1,2,0)− where the ± refers both to the direction of automotion and the two arrangements (N+, S−) and (N−,S+) of Bloch line polarity and sense of twist. The automotion arises because the translational coercive force couples to motions of the wall radius and the Bloch lines. Unichiral bubbles χ±=(100)± of either handedness (±) do not automote. Excitations outside the range for automotion can cause changes in wall structure. We show how to switch at will among σ−, +, χ− and χ+ states.