gebhart/patrepeval huggingface dataset:
Variable threshold voltage keeper for contention reduction in dynamic circuits (2003)

A variable threshold voltage keeper circuit technique is proposed for simultaneous power reduction and speed enhancement of domino logic circuits. The threshold voltage of the keeper transistor is dynamically modified during circuit operation to reduce the contention current without sacrificing noise immunity. A four-bit multiple-output domino carry generator for a carry lookahead adder is designed with the proposed circuit technique. It is shown that the variable threshold voltage keeper circuit technique enhances the circuit evaluation speed by up to 60% while reducing power dissipation by 37% as compared to a standard domino logic circuit. It is also shown that the proposed domino logic circuit technique offers 20% higher noise immunity as compared to a standard domino circuit with the same evaluation delay characteristics.
Demonstration of a Titled-Pulse-Front Pumped Plane-Parallel Slab Terahertz Source (2019)

The study and control of materials with extremely strong THz fields [1, 2], or the acceleration and manipulation of electrons [3] and protons [4] are emerging applications which require THz sources with unprecedented parameters. Optical rectification of femtosecond pulses with tilted pulse front in lithium niobate (LN) [5] has become a standard technique for efficient THz generation. Conventionally [1, 5, 6], a prism-shaped LN crystal is used with a large wedge angle equal to the pulse-front tilt (63°). This results in a nonuniform pump propagation length across the beam, which lead to a spatially varying interaction length for THz generation. This negatively affects the THz beam quality and focusability, thereby limiting the achievable field strength. In order to provide uniform interaction length across large pump and THz beams, we have proposed a setup, where the nonlinear medium is a plane-parallel LN slab with an echelon structure on its input surface [7] (NLES, Fig. 1). Inside the LN slab, a segmented tilted pulse front is formed with an average tilt angle as required by phase matching.
Dendrimer nanotechnology for enhanced formulation and controlled delivery of resveratrol (2015)

In spite of its wide and beneficial pharmacological potential, resveratrol lags behind other compounds because of its comparatively less impressive pharmacokinetic profile. Resveratrol has very low oral bioavailability and, from a formulation perspective, it has low solubility in water, which leads to its poor absorption upon oral administration. Apart from low aqueous solubility, resveratrol has poor metabolic stability and instability at high pH, and is photosensitive. The pharmacokinetic and formulation‐related limitations of resveratrol can be controlled by entrapping the small resveratrol molecule inside highly water‐soluble poly(amidoamine) dendrimer nanostructures, which provide spherical architecture and polyvalency at the nanoscale level, thus leading to novel features. Dendrimer architecture is used to entrap resveratrol for enhancement of its solubility and stability in aqueous solution; they can be engineered to control pharmacokinetics and targeting for oral, mucosal, transdermal, or parenteral administration. Dendrimers have the potential to work as excipients with multifunctional capability by enhancing solubility, dissolution, stability, permeability, multiple drug/cosmetic entrapment, controlled delivery, bioavailability, and efficacy of drugs.
A Flow-Through, Hybrid Magnetic-Field-Gradient, Rotating Wall Device for Magnetic Colloidal Separations (2000)

A 2.0 cm internal diameter 1 m long, axially-rotating horizontal glass tube, with four axially located repeating hybrid magnetic units, is used as part of a flow-through, colloidal magnetic affinity separation device. Each magnetic unit consists of an alternating current solenoid surrounding the chamber followed by four azimuthally distributed permanent magnets that rotate with the chamber. Experiments were carried out on a model feed system consisting of a mixture of 1.0 μm diameter biotinylated latex beads (targets) and 9.7 μm diameter nonfunctionalized latex beads (nontargets) at a 1:1 number ratio. Streptavidin labeled magnetic particles (2.8 μm diameter polystyrene - Dynabeads) at a number concentration of ˜3 x 106 beads/mL were used as the separation vehicles. Two feed flow rates of 12 and 35 mL/min were used until a total of 600 mL of sample were processed for each. At the low rate we achieved a capture efficiency of 60 ± 4% and a separation factor of 18.2 ± 1.2 with 95 ± 4% purity. For the higher flow rate the capture efficiency was 40 ± 4% and the separation factor was 18.6 ± 1.5 with 87 ± 4% purity. A single stage batch process, where a total of 10 mL of feed was processed at identical feed and magnetic bead concentrations required ˜2 hours, produced a capture efficiency of 42 ± 4% and a separation factor of 3.8 ± 1 with 79 ± 4% purity. Three batch stages (2 hours processing time per stage) were required to surpass the capture efficiency of the flow-through device at the smaller flow rate. Thus, this flow-through separation device can lead to a large increase in processing volume and reduced ’down’ time, compared to current batch processes, without loss of either efficiency or purity, potentially opening up magnetic colloidal separations for large scale applications.
Evaluating Immediate Benefits of Assisting Knee Extension With a Soft Inflatable Exosuit (2020)

Wearable robots such as powered exoskeletons and exosuits have been developed for gait assistance and rehabilitation. However, effects of knee extension assistance during the swing phase and initial stance of walking remains largely unknown. This work studies the changes in gait patterns for seven healthy participants and three impaired participants when knee extension in the swing and initial stance phases is assisted by a soft inflatable exosuit. The kinematics, surface electromyographic (sEMG) activity, and ground reaction forces (GRFs) for seven healthy participants during treadmill walking are recorded. Reductions in knee angle and sEMG activity of the quadriceps are observed. The knee angles, GRFs, spatiotemporal parameters, and compensatory gait patterns are studied for the three impaired participants for treadmill walking. Reductions in the knee angle, hip flexion, step length, and step time are observed. Compensatory gait patterns for the three participants varied for all participants. A timed up-and-go (TUG) test is also performed with the impaired participants during overground walking. A reduced TUG execution time is observed, indicating potential improvement in functional mobility. Overall, this work provides preliminary evidence on the benefits of a soft-exosuit in supporting healthy individuals and improving the rehabilitation of stroke survivors by assisting knee extension in the swing and initial stance phases.
COMPARING MR IMAGING PROPERTIES OF SPIRAL TRAJECTORIES USING THE SINGULAR SPECTRUM OF THE ANALYTICAL FOURIER BASIS CROSS-CORRELATION MATRIX (2007)

We compare fixed and variable density and randomized spiral trajectories for MR imaging in terms of PSF resolution and stopband ripple and noise amplification, with the singular value spectrum of the cross-correlation Fourier basis matrix as an analysis tool. We explain the rationale behind using that matrix and why its singular spectrum is meaningful. We show that the relative number of singular values above an easily determined threshold is an indicator of resolution, and the shape of the rest of the spectrum an indicator of noise vs. reconstruction accuracy tradeoffs.
Novel Gate Structure for High Voltage Light-Triggered Thyristor (1982)

This paper presents a novel gate structure for a high power light-triggered thyristor, which is easily fired with a light-triggering system consisting of a commercially available LED and optical fibers. The key features of the novel gate structure are its light sensitive area surface consisting of a central P-base portion, and its surrounding stepwise deep diffused N-emitter with more than 70% to 75% quantum efficiency. A 4 kV-1.5 kA directly light-triggered thyristor was developed using the novel gate structure as a first pilot thyristor for a newly developed multi-stage amplifying gate, satisfying excellent overall characteristics of 2.5 mW minimum light triggering power, 250 A/µs d i /d t capability and 1.5 kV/µs d v /d t capability, as well as high voltage turn-on testing from 4 kV rated full blocking voltage without d i /d t failure.
A flow-driven fast forwarding architecture for content centric networks (2015)

Content-centric Networking (CCN) promises significant advantages over the current Internet architecture by replacing its host-centric design with a content-centric one, and enabling in-network caching and name-based forwarding. However, despite its advantages, wire-speed forwarding in CCN remains a challenge, as CCN uses stateful forwarding and requires lookups on packets carrying hierarchically structured and variable-length content names. As a result, storage and computing requirements to support name-based forwarding in CCN typically determines the forwarding capacity. In this paper, to address the forwarding scalability concerns in CCN, we propose an overlay forwarding architecture that utilizes flow-driven adaptive forwarding and tradeoffs between flexibility and scalability. The proposed architecture exploits the correlations in user traffic to create active flow states in content routers to bypass the default CCN forwarding for future requests. We present an indepth study of the proposed architecture and provide demonstrative results on its performance proving its scalability and effectiveness.
Substituted Polypyridine Complexes of Cobalt(II/III) as Efficient Electron-Transfer Mediators in Dye-Sensitized Solar Cells (2002)

A number of cobalt complexes of substituted polypyridine ligands were synthesized and investigated as possible alternatives to the volatile and corrosive iodide/triiodide redox couple commonly used as an electron-transfer mediator in dye-sensitized solar cells (DSSCs). The extinction coefficients in the visible spectrum are on the order of 10(2) M(-1) cm(-1) for the majority of these complexes, diminishing competition with the light-harvesting dye. Cyclic voltammetric studies revealed a dramatic surface dependence of the heterogeneous electron-transfer rate, which is surprisingly different for gold, carbon, and platinum electrodes. DSSCs were assembled using a mediator that consisted of a mixture of Co(II) and Co(III) complexes in a 10:1 ratio. DSSCs containing these mediators were used to characterize incident photon-to-current conversion efficiency and photoelectrochemical responses. The best performing of these mediators were identified and subjected to further study. As suggested by electrochemical results, gold and carbon are superior cathode materials to platinum, and no evidence of corrosion on any cathode material was observed. Addition of lithium salts to the mediator solution resulted in a dramatic improvement in cell performance. The observed Li(+) effect is explained in terms of the recombination of injected electrons in the photoanode with the oxidized mediator. The best mediator, based on tris(4,4'-di-tert-butyl-2,2'-dipyridyl)cobalt(II/III) perchlorate, resulted in DSSCs exhibiting efficiencies within 80% of that of a comparable iodide/triiodide-mediated DSSC. Due to the commercial availability of the ligand and the simplicity with which the complex can be made, this new mediator represents a nonvolatile, noncorrosive, and practical alternative as an efficient electron-transfer mediator in DSSCs.
All-Digital RF Phase-Locked Loops Exploiting Phase Prediction (2014)

This paper presents an all-digital phase-locked loop (ADPLL) architecture in a new light that allows it to significantly save power through complexity reduction of its phase locking and detection mechanisms. The predictive nature of the ADPLL to estimate next edge occurrence of the reference clock is exploited here to reduce the timing range and thus complexity of the fractional part of the phase detection mechanism as implemented by a time-to-digital converter (TDC) and to ease the clock retiming circuit. In addition, the integer part, which counts the DCO clock edges, can be disabled to save power once the loop has achieved lock. It can be widely used in fields of fractional-N frequency multiplication and frequency/phase modulation. The presented principles and techniques have been validated through extensive behavioral simulations as well as fabricated IC chips.
Linearization of electro-optic modulators by a cascade coupling of phase-modulating electrodes (1991)

Theoretical predictions and experimental results on two slightly different kinds of linearized optical modulators for use in wideband analog transmission is presented. Both modulators are based on a cascade coupling of phase-modulated parallel wave guide sections. In both cases, 95 dB suppression of the 3rd harmonic of a single test tone with an optical modulation depth of 20% is theoretically obtained. Some initial experimental results are presented for both modulators.
Investigations on the robustness of particle separation in multi-color magnetic particle imaging (2015)

Many applications of magnetic particle imaging (MPI) would benefit from the ability to distinguish different types of particles that are measured simultaneously. For instance, using “multi-color” MPI [1], a catheter marked with one type of particles could be visualized in a different color than the surrounding blood marked with a second type of particles.
Enhancement of biomolecular detection sensitivity by surface plasmon resonance ellipsometry (2005)

We present the application of ellipsometry to the phase measurement of surface plasmon resonance (SPR) in biomolecular detection. In this configuration, the phase measurement gives a large enhancement of detection sensitivity in comparison to traditional SPR techniques. In this work, the experimental setup for SPR ellipsometry is based on both custom-built rotating analyzer ellipsometer and an imaging ellipsometer which are equipped with a SPR-cell and a flow system, respectively. We investigate the adequate thickness of the gold layer used for SPR cell and the resolution of the phase detection using two ellipsometric methods under the SPR condition. The rotating analyzer method yields higher sensitivity sufficient to detect changes in the effective thickness of biomolecular layers of less than 1 pm. In comparison to conventional SPR the simultaneous measurement of ellipsometric parameters, Δ and ψ, yields more information which is useful for quantitative analysis based on fitting theoretical solutions to experimental results.
Overcoming Barriers in Polycarbonate Synthesis: A Streamlined Approach for the Synthesis of Cyclic Carbonate Monomers (2021)

Accessing cyclic carbonate monomers on a large scale is critical for the development of any new carbonate-based materials platform. The synthesis of carbonate monomers can be a challenging and tedious endeavor requiring multiple synthetic steps and purifications. To address this, we report a drastically improved process for the synthesis of carbonate monomers via a two-step route that avoids the use of hazardous triphosgene or chloroformate reagents. This process enables rapid access to a broad array of functional groups on the carbonate monomer and the monomers generated from the procedure can readily be polymerized via ring-opening polymerization.
Major Challenges and Opportunities in Silicon Solar Panel Recycling (2020)

This paper examines three recycling scenarios for silicon panels: panel reuse, component extraction, and material extraction. Recycling process sequences, recycling technologies, and potential revenues for different scenarios are discussed. The main conclusions of the paper include: 1) separation of silicon cells from glass is a critical technology; 2) low-concentration silver and lead must be recovered from silicon panels; 3) markets outside the solar industry for the recovered silicon should be explored; and 4) cell efficiency standardization can improve the recyclability of silicon panels.
Novel insecticidal peptides fromTegenaria agrestis spider venom may have a direct effect on the insect central nervous system (1998)

Fractionation of venom from an agelenid spider, Tegenaria agrestis, resulted in the isolation of a family of three peptides with potent insecticidal activity. These peptide toxins, TaITX-1, -2, and -3, whose sequences were revealed from cloned cDNAs, each consist of 50 amino acid residues, six of which are cysteines. They appear to be amidated at their C-termini and exhibit greater than 90% sequence identity. Unlike other reported spider toxins, the TaI toxins are processed from precursors containing no propeptide sequences. In lepidopteran larvae and corn rootworm beetles, the insecticidal Tegenaria toxins caused an unusual excitatory symptomatology with 50% paralytic doses ranging from 0.23 to 2.6 nmol/g. In a series of electrophysiological experiments performed in house fly larvae, these toxins caused an elevated rate of firing from central nervous system neurons. No significant effects were found when any peripheral sensory or motor systems were examined. Thus, it appears that the TaI toxins may act in a fashion not previously reported for insecticidal peptide toxins; they may act directly on the insect central nervous system.
Appearance Harmonization for Single Image Shadow Removal (2016)

Shadows often create unwanted artifacts in photographs, and removing them can be very challenging. Previous shadow removal methods often produce de-shadowed regions that are visually inconsistent with the rest of the image. In this work we propose a fully automatic shadow region harmonization approach that improves the appearance compatibility of the de-shadowed region as typically produced by previous methods. It is based on a shadow-guided patch-based image synthesis approach that reconstructs the shadow region using patches sampled from non-shadowed regions. The result is then refined based on the reconstruction confidence to handle unique image patterns. Many shadow removal results and comparisons are show the effectiveness of our improvement. Quantitative evaluation on a benchmark dataset suggests that our automatic shadow harmonization approach effectively improves upon the state-of-the-art.
Circulating Levels and Molecular Distribution of the Acid-Labile (<i>α</i>) Subunit of the High Molecular Weight Insulin-Like Growth Factor-Binding Protein Complex* (1990)

A RIA is described for the acid-labile (alpha) subunit of the high mol wt insulin-like growth factor (IGF)-binding protein complex, a glycoprotein of approximately 85,000 daltons (approximately 85K) which combines with the GH-dependent binding protein (BP-53 or IGFBP-3) and IGF-I or IGF-II to form the complex. The assay shows relative specificity for higher primate species. Whereas amniotic fluid, cerebrospinal fluid, and seminal plasma contain virtually no immunoreactive alpha-subunit, the protein is easily detectable in 0.5-microL serum samples. Serum alpha-subunit levels are markedly age dependent, rising over 5-fold from birth to puberty, then remaining relatively constant throughout adulthood. In 170 children, there was a strong association between alpha-subunit and IGFBP-3 levels. Mean alpha-subunit levels (+/- SD) in adults were 24.2 +/- 4.7 mg/L in 93 normal subjects, 54.1 +/- 15.5 mg/L in 12 acromegalics, 6.5 +/- 4.8 mg/L in 10 GH-deficient subjects, and 31.5 +/- 5.7 mg/L in 18 third term pregnant women. In serum fractionated by gel chromatography, alpha-subunit appeared as a broad 100-150K peak. After depleting serum samples of IGFBP-3 by immunoaffinity chromatography, approximately one third of alpha-subunit remained, in a peak of about 100K, suggesting that two thirds of the total alpha-subunit in serum is present in the approximately 150K complex, and one third is uncomplexed. Development of this RIA for alpha-subunit will allow further study of regulation of the GH-dependent complex.
Embedding and characterization of fiber‐optic and thin‐film sensors in metallic structures (2004)

It is often important to acquire information such as temperature and strain values from metallic tools and structures in situ . With embedded sensors, structures are capable of monitoring parameters at critical locations not accessible to ordinary sensors. To embed sensors in the functional structures, especially metallic structures, layered manufacturing is a methodology capable of rapidly and economically integrating sensors during the production of tooling or structural components. Embedding techniques for both fiber‐optic sensors and thin‐film sensors have been developed.
Properties of Pb-Doped Bi-Sr-Ca-Cu-O Superconductors Prepared by the Intermediate Pressing Process (1989)

Effects of an intermediate press process on the microstructure and superconducting properties of the Pb-doped Bi-Sr-Ca-Cu-O system have been studied. Samples were made by sintering uniaxially pressed pellets after the conventional pellet-sintering process. Highly textured microstructure with strong (001) reflections was confirmed by X-ray diffraction and SEM. A short sintering time was sufficient to form only the high- T c phase. By this intermediate pressing and sintering process, J c was much increased and the magnetic field dependence of J c was also improved. The highest J c achieved was 3560 A/cm 2 at 0 T and 77.3 K.
<title>Errors caused by nearly parallel optical elements in a laser Fizeau interferometer utilizing strictly coherent imaging</title> (1997)

Most commercial laser Fizeau interferometers employ a rotating diffuser on an intermediate image plane. The image formed on this plane is relayed to the detector using incoherent imaging, eliminating potential interference effects from elements after the diffuser. Systems requiring high spatial frequency resolution cannot employ the diffuser or incoherent relay system to the degradation they cause to the system transfer function.With strictly coherent imaging, however, nearly parallel optical elements such as the CCD cover glass will produce interference fringes. Though these elements are common path, fringes will be visible in the phase measurements unless one of several specific conditions are met. This paper explores the theory behind the formation of these fringes and examines cases where this error may be eliminated. Theoretical calculations are compared with actual measurements taken on a laser Fizeau interferometer. The errors evident in the final phase measurements may be minimized with proper coating of the system optics, sufficient wedge in the elements, or removal of the nearly parallel elements from the system.
Multidimensional benzobisoxazole rigid-rod polymers. II. Processing, characterization, and morphology (1997)

A high-torque rheometer was used to facilitate the polycondensation of 4-[5-amino-6-hydroxybenzoxazol-2-yl]benzoic acid (ABA) with trimesic acid and 1,3,5,7-tetrakis(4-carboxylatophenyl)adamantane to yield two- and three-dimensional benzobisoxazole polymers, respectively. Although the resultant polymer dopes exhibited improved homogeneity compared to polymer dopes previously prepared in glassware, improved polymer solution viscosities were not achieved. Fibers spun from the two- and three-dimensional polymers did not show a significant increase in compressive strength compared to fibers of the linear or one-dimensional benzobisoxazole polymer derived from the homopolymerization of ABA. Morphological studies of the polymer fibers and films by wide-angle X-ray scattering and scanning electron microscopy strongly indicated more lateral disorder and a more isotropic character for the three-dimensional structures compared to the one-dimensional structures. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3457–3466, 1997