gebhart/patrepeval huggingface dataset:
The aerocapacitor: An electrochemical double-layer energy-storage device (1997)

The authors have applied unique types of carbon foams developed at Lawrence Livermore National Laboratory (LLNL) to make an {open_quotes}aerocapacitor{close_quotes}. The aerocapacitor is a high power-density, high energy-density, electrochemical double-layer capacitor which uses carbon aerogels as electrodes. These electrodes possess very high surface area per unit volume and are electrically continuous in both the carbon and electrolyte phase on a 10 nm scale. Aerogel surface areas range from 100 to 700 m{sup 2}/cc (as measured by BET analysis), with bulk densities of 0.3 to 1.0 g/cc. This morphology permits stored energy to be released rapidly, resulting in high power densities (7.5 kW/kg). Materials parameterization has been performed, and device capacitances of several tens of Farads per gram and per cm{sup 3} of aerogel have been achieved.
A General Method for Convergent Synthesis of Polycyclic Ethers Based on Suzuki Cross-Coupling:  Concise Synthesis of the ABCD Ring System of Ciguatoxin (1999)

A general method for convergent assembly of polyether structure has been developed based on palladium(0)-mediated Suzuki cross-coupling reaction of alkylboranes with cyclic ketene acetal phosphates. The present method allowed for coupling of medium-sized ether rings and thus a concise synthesis of the ABCD ring system of ciguatoxins has been achieved.
Experimental demonstration of vector E x vector B plasma divertor (1977)

The vector E x vector B drift due to an applied radial electric field in a tokamak with poloidal divertor can speed the flow of plasma out of the scrape-off region, and provide a means of externally controlling the flow rate and thus the width of the density fall-off. An experiment in the Wisconsin levitated toroidal octupole, using vector E x vector B drifts alone, demonstrates divertor-like behavior, including 70% reduction of plasma density near the wall and 40% reduction of plasma flux to the wall, with no adverse effects on confinement of the main plasma.
1,3-Halogen migration as an entry to aryl coppers from an unintuitive starting material (2014)

A copper(I) catalyzed 1,3-halogen migration/borylation migrates a bromine from an sp(2) carbon to a benzylic carbon with concomitant borylation of the aryl-bromine bond. This transformation proceeds via an aryl copper intermediate which can be accessed independently and then trapped with electrophiles. As such, copper-catalyzed 1,3-halogen migration provides unique and mild access to an aryl copper species that allows for rapid aromatic functionalization from an unconventional starting material.
Effect of bismuth content on the properties of Sr0.8BixTa1.2Nb0.9O9+y ferroelectric thin films (1999)

This study investigates the effect of bismuth content on the ferroelectric properties of Sr0.8BixTa1.2Nb0.9O9+y (SBTN, x=1.7, 2.0, 2.5, 2.7, 2.9, and 3.2) thin film capacitors. SBTN films are in situ grown on Pt/SiO2/Si substrates by using two-target off-axis radio-frequency magnetron sputtering at a substrate temperature of 600 °C. The films are crystallized with a high (115) diffraction intensity and exhibit a columnar microstructure. Experimental results indicate that the root mean square surface roughness of the film increases with an increase of the bismuth content. In addition, the ferroelectric properties of the films heavily rely on the bismuth content. Moreover, the 440-nm-thick Sr0.8Bi2.5Ta1.2Nb0.9O9+y films exhibit maximum remanent polarization (2Pr) of 52 μC/cm2 and minimum coercive field (2Ec) of 28 kV/cm at an applied voltage of 1.5 V. X-ray photoelectron spectral studies reveal that except for Bi+3, no lower valence state bismuth exists in the Sr0.8Bi2.5Ta1.2Nb0.9O9+y film and bismuth substituted in the strontium site still remains in its +3 valence state.
High spatial resolution time-of-flight imaging (2018)

Continuous wave time-of-flight (ToF) cameras have been rapidly gaining widespread adoption in many applications due to their cost effectiveness, simplicity, and compact size. However, the current generation of ToF cameras suffers from low spatial resolution due to physical fabrication limitations. In this paper, we propose an imaging architecture to achieve high spatial resolution ToF imaging using optical multiplexing and compressive sensing (CS). Our approach is based on the observation that, while depth is non-linearly related to ToF pixel measurements, a phasor representation of captured images results in a linear image formation model. We utilize this property to develop a CS-based technique that is used to recover high resolution 3D images. Based on the proposed architecture, we developed a prototype 1-megapixel compressive ToF camera that achieves as much as 4 x improvement in spatial resolution. We believe that our proposed architecture provides a simple and low-cost solution to improve the spatial resolution of ToF and related sensors.
Dynamic Assembly of Human Salivary Stem/Progenitor Microstructures Requires Coordinated α1β1 Integrin-Mediated Motility (2019)

A tissue engineering approach can provide replacement salivary gland structures to patients with hyposalivation disorders and xerostomia. Salivary human stem/progenitor cells (hS/PCs) were isolated from healthy regions of parotid glands of head and neck surgery patients, expanded, then encapsulated in biocompatible hyaluronate (HA)-based hydrogels. These bioactive hydrogels provide a surrogate territorial matrix suitable for the dynamic assembly, growth and reorganization of salivary gland components. This study examined the dynamics of salivary microstructure formation, growth, and reorganization using time-lapse imaging over 15 h. Immunofluorescence detection monitored production of individual basement membrane components forming around developing microstructures, and Ki67 assessed proliferation. Dynamic movements in hydrogels were quantified by measuring angular velocity (ω) of rotating salivary microstructures and changes in basement membrane architecture during microstructure growth. Integrin involvement in the dynamic reassembly was assessed using knockdown and inhibitor approaches. Single hS/PCs expanded over 5 days into spherical microstructures typically containing 3-10 cells. In larger macrostructures, proliferation occurred near the peripheral basement membrane that underwent growth-associated cycles of thinning and collapse. <i>De novo</i> secretion of laminin/collagen IV from reorganizing hS/PCs preceded that of perlecan/HSPG2. Microstructures routinely expressed β<sub>1</sub> integrin-containing complexes at basement membrane-associated regions and exhibited spontaneous and coordinated rotation during basement membrane maturation. β<sub>1</sub> integrin siRNA knockdown at the single-cell state prevented hS/PC microstructure growth. After microstructure formation, β<sub>1</sub> integrin knockdown reduced rotation and mean ω by 84%. Blockade of the α<sub>1</sub> integrin subunit (CD49a) that associates with β<sub>1</sub> reduced mean ω by 66%. Studies presented here show that initial hS/PC structure growth and basement membrane maturation depends on α<sub>1</sub>β<sub>1</sub>-integrin mediated signaling. Coordinated cellular motility during neotissue reorganization reminiscent of salivary gland acini was critically dependent both on hS/PC-secretion of laminin,collagen type-IV, and perlecan/HSPG2 and the force-driven interactions of α<sub>1</sub>β<sub>1</sub>-integrin activation. We conclude that α<sub>1</sub>β<sub>1</sub>-integrin plays a critical role in establishing human salivary gland coordinated structure and function, and that its activation in tissue engineered systems is essential to tissue assembly.
Site Selective C-H Functionalization of Mitragyna Alkaloids Reveals a Molecular Switch for Tuning Opioid Receptor Signaling Efficacy (2020)

<p>Mitragynine is the most abundant alkaloid component of the psychoactive plant material “kratom”, which according to numerous anecdotal reports shows efficacy in self-medication for pain syndromes, depression, anxiety, and substance use disorders. We developed a new synthetic method for selective functionalization of the unexplored C11 position of the mitragynine scaffold (C6 position in indole numbering) via the use of an indole-ethylene glycol adduct and subsequent iridium-catalyzed borylation. We discovered that C11 represents a key locant for fine-tuning opioid receptor signaling efficacy. In the 7-hydroxymitragynine (7OH) series, the high efficacy parent compound was transformed to an equipotent low efficacy agonist by introducing a fluorine substituent in this position (11-F-7OH), as demonstrated in vitro at both mouse and human mu opioid receptors (mMOR/hMOR) and in vivo in mouse analgesia tests after systemic administration. Low efficacy opioid agonists are of high interest as candidates for generating safer opioid medications with mitigated adverse effects.</p>
Temperature dependence of amorphous silicon solar cell PV parameters (2002)

The temperature behavior of amorphous silicon (a-Si) based solar cells was measured for cells made under different fabrication conditions and with different thermal and illumination histories. Amorphous silicon solar cells exhibit a complex temperature behavior that depends on processing history and cannot be characterized by a unique temperature coefficient as in the case of crystalline silicon solar cells. In general, a-Si solar cells exhibit relatively little temperature dependence once they are operating in an equilibrated state, but they will exhibit a relatively strong temperature dependence over short periods of time. Both the short-term temperature dependence and the stabilized output power depend on several factors such as the device configuration, the defect concentration in the i-layer, the thickness of the i-layer and the light soaking temperature.
A simple single switch electronic ballast for compact fluorescent lamps with passive power factor correction (PFC) and soft switching capability (2012)

This paper presents a simple, high power factor single switch electronic ballast for compact fluorescent lamp (CFL). Conventional CFLs on the market are not able to achieve the same power factor performance as the incandescent lamp does, which presents a significant problem for the utility with the gradual widespread use of CFL in the near future. In this paper, a single switch electronic ballast topology with passive power factor correction (PFC) is proposed. The PFC circuit is a valley fill circuit and the proposed single switch resonant inverter is able to achieve zero current switching. Detailed descriptions of the circuit operating principles are provided in this paper. Simulation and experimental results are given on a 13W CFL tube to highlight the merits of the proposed work.
Improving Perception in Time Delayed Teleoperation (2006)

Telerobotics has long struggled to provide realistic force feedback to the user, especially across substantial time delays. Wave variable based controllers provide stable force reflection at frequencies up to a few Hertz for typical communication delays; however, the bandwidth of human perception extends to a thousand Hertz. We address this problem by incorporating a force sensor at the slave end effector and creating an additional feedback path to provide high frequency force information to the user. We build this augmented feedback system on top of a normal wave variable controller, leveraging the separation of power flows provided by the wave variable formalism and building a fundamentally asymmetric controller that better matches the sensory capabilities of the human operator. To further improve the user’s perception of the slave site, we investigate the use of wave filters to compensate for wave reflections without introducing the excessive damping inherent to impedance matching. Both of these improvements are validated experimentally in a simple three degree of freedom teleoperator.
Continuous-Time Optimization of Time-Varying Cost Functions via Finite-Time Stability with Pre-Defined Convergence Time (2020)

In this paper, we propose a new family of continuous-time optimization algorithms for time-varying, locally strongly convex cost functions, based on discontinuous second-order gradient optimization flows with provable finite-time convergence to local optima. To analyze our flows, we first extend a well-know Lyapunov inequality condition for finite-time stability, to the case of arbitrary time-varying differential inclusions, particularly of the Filippov type. We then prove the convergence of our proposed flows in finite time. We illustrate the performance of our proposed flows on a quadratic cost function to track a decaying sinusoid.
Biocompatible and Biodegradable Copolymer Stabilizers for Hydrofluoroalkane Dispersions:  A Colloidal Probe Microscopy Investigation (2007)

In this work we investigate the ability of biodegradable and biocompatible lactide-based nonionic amphiphiles to stabilize a model drug (salbutamol base) dispersion in hydrofluoroalkane (HFA) propellant. A series of triblock copolymers of the type poly(lactide)-poly(ethylene glycol)-poly(lactide) (LA(m)EO(n)LA(m)) with varying molecular weight (MW) and % EO were synthesized. The cohesive forces between drug particles in liquid HFA in the presence of the amphiphiles were quantitatively determined by colloidal probe microscopy (CPM). The effect of cosolvent, oleic acid, and a nonionic triblock copolymer with the propylene oxide moiety as the HFA-phile was also investigated. CPM results show that the overall concentration, MW, surfactant tail (LA) length, and the ratio between the stabilizing LA moiety and the anchor EO group have a great impact on the drug cohesive forces. The CPM results in liquid HFA were correlated to the bulk physical stability of the drug suspensions in the propellant 1,1,1,2,3,3,3-heptafluoropropane (HFA227). The dispersions in HFA227 were significantly improved in the presence of LA(m)EO(n)LA(m), correlating well with the low cohesive forces determined by CPM. The applicability of LA-based amphiphiles might be extended to other suspension-based formulations provided a suitable headgroup is found. This study is relevant for the development of HFA-based dispersion pressurized metered-dose inhaler formulations.
Inhibition of Stat1-mediated gene activation by PIAS1 (1998)

STAT (signal transducer and activator of transcription) proteins are latent cytoplasmic transcription factors that become activated by tyrosine phosphorylation in response to cytokine stimulation. Tyrosine phosphorylated STATs dimerize and translocate into the nucleus to activate specific genes. Different members of the STAT protein family have distinct functions in cytokine signaling. Biochemical and genetic analysis has demonstrated that Stat1 is essential for gene activation in response to interferon stimulation. Although progress has been made toward understanding STAT activation, little is known about how STAT signals are down-regulated. We report here the isolation of a family of PIAS (protein inhibitor of activated STAT) proteins. PIAS1, but not other PIAS proteins, blocked the DNA binding activity of Stat1 and inhibited Stat1-mediated gene activation in response to interferon. Coimmunoprecipitation analysis showed that PIAS1 was associated with Stat1 but not Stat2 or Stat3 after ligand stimulation. The in vivo PIAS1-Stat1 interaction requires phosphorylation of Stat1 on Tyr-701. These results identify PIAS1 as a specific inhibitor of Stat1-mediated gene activation and suggest that there may exist a specific PIAS inhibitor in every STAT signaling pathway.
Blind estimation of reverberation time using deep neural network (2016)

In this paper, we propose a method to estimate reverberation time (T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">60</sub> ) from the observed reverberant speech signal using deep neural network (DNN). Reverberation of speech signal is a critical issue in speech processing as the reverberation results smearing of the sound characteristics in both temporal and spectral domain resulting unfavorable effects on the performance of speech processing algorithms. Employing room acoustic characteristics of a reverberant speech can enhance the performance of the speech processing system so that the blind estimation of reverberation time has been studied based on the numerical interpretation of reverberation. In this paper, we adopt the speech decay rate and its distribution for each frequency bin as input feature vectors of DNN. Complex relation between each input feature vector and each T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">60</sub> target label through multiple nonlinear hidden layers. We also introduce an approach to mitigate the computational complexity whilst maintaining rational performance.
Someone in Your Contact List: Cued Recall-Based Textual Passwords (2017)

Textual passwords remain the most commonly employed user authentication mechanism, and potentially will continue to be so for years to come. Despite the well-known security and usability issues concerning textual passwords, none of the numerous proposed authentication alternatives appear to have achieved a sufficient level of adoption to dominate in the foreseeable future. Password hints, consisting of a user generated text saved at the account setup stage, are employed in several authentication systems to help users to recall forgotten passwords. However, users are often unable to create hints that jog the memory without revealing too much information regarding the passwords themselves. We propose a rethink of password hints by introducing SỲNTHIMA, a novel cued recall-based textual password method that reveals no information regarding the password, requires no modifications to authentication servers, and requires no additional setup or registration steps. SỲNTHIMA makes use of users' contact lists, so that mapped password hints extracted from a user's contacts are automatically generated while the user is typing the password. We create formal models for relevant aspects of the password hint mechanism, define its threat model, and analyze the security and usability of SỲNTHIMA. We also present the results of an in-lab user study of SỲNTHIMA on 30 participants to evaluate its effectiveness and usability. The results demonstrate that SỲNTHIMA minimizes the number of incorrect login attempts and improves long-term password recall, with acceptable login times and positive user feedback. We summarize the lessons learned from the user study, with the hope of provoking further insights regarding the design of effective cued recall-based textual password schemes.
Automatic White Balance for Digital Still Cameras (2006)

In recent years digital cameras have captured the camera market. Although the factors that consumer consider is the quality of the photographs produced. White balance is one of the methods used to improve the quality of the photographs. The basic white balance methods are, however powerless to handle all possible situations in the captured scene. In order to improve the white balance we divide this problem in three steps-white object purification, white point detection, and white point adjustment. The proposed method basically solves the problem of detecting the white point very well. The experimental results show that the proposed method can achieve superior result in both objective and subjective evaluative terms. The complexity of the proposed system is acceptable. The propose method can be easily applied to digital cameras to obtain good results.
Theory of ferromagnetic hysteresis: evaluation of stress from hysteresis curves (1988)

A recent extension of the theory of ferromagnetic hysteresis to include the effects of a constant applied stress uses an effective field H/sub sigma / that depends on the stress and the rate of change of magnetostriction with magnetization. The extended theory is used here to derive a particularly simple expression for the variation with stress of the anhysteretic differential susceptibility at M=O, H=O. The theoretical prediction is compared with experimental results and shows excellent agreement. This expression forms the basis for a novel technique of evaluating stress in ferromagnetic steels.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Schizosaccharomyces pombe Cells Deficient in Triacylglycerols Synthesis Undergo Apoptosis upon Entry into the Stationary Phase (2003)

Triacylglycerols (TAG) are important energy storage molecules for nearly all eukaryotic organisms. In this study, we found that two gene products (Plh1p and Dga1p) are responsible for the terminal step of TAG synthesis in the fission yeast Schizosaccharomyces pombe through two different mechanisms: Plh1p is a phospholipid diacylglycerol acyltransferase, whereas Dga1p is an acyl-CoA:diacylglycerol acyltransferase. Cells with both dga1+ and plh1+ deleted (DKO cells) lost viability upon entry into the stationary phase and demonstrated prominent apoptotic markers. Exponentially growing DKO cells also underwent dramatic apoptosis when briefly treated with diacylglycerols (DAGs) or free fatty acids. We provide strong evidence suggesting that DAG, not sphingolipids, mediates fatty acids-induced lipoapoptosis in yeast. Lastly, we show that generation of reactive oxygen species is essential to lipoapoptosis.
Design of a Surgical Port for Minimally Invasive Beating-Heart Intracardial Procedures (2011)

Direct-access, minimally invasive, beating-heart intracardial procedures have the potential to replace many traditional surgical procedures requiring cardio-pulmonary bypass as long as micro-emboli are prevented from entering the cardiovascular system. A new surgical port was developed to introduce surgical instruments into chambers of the beating heart during minimally invasive, intracardial surgical procedures without allowing the introduction of micro-emboli 0.1 mm or larger in size. The design consists of an outer port body that is secured to the heart wall using a purse string suture and a series of inner tubular sleeves that form the interface between the port and the transecting instrument. The design enables rapid tool changes and accommodates a wide variety of instruments. The port uses a fluid purging system to dislodge and remove emboli from a surgical instrument. Laboratory and clinical tests show that the port adequately seals around a surgical instrument and prevents the introduction of emboli with diameters greater than 0.1 mm into the heart while minimizing hemorrhage.
From Finite to Infinite Volumes: Removal of Boundaries in Diffuse Wave Imaging (2006)

In this Letter, we present a method that removes the contribution of the boundaries on the measurements from highly scattering media, transforming the signals captured from a bounded medium to measurements that would have been obtained if no boundary were present. This approach opens new possibilities in tomographic imaging in diffuse media as it eliminates the need for explicitly modeling boundaries and significantly simplifies reconstruction requirements.
Multimodal three-dimensional imaging with isotropic high resolution using optical projection tomography (2009)

The optical projection tomography microscope (OPTM) is an optical microscope that acquires focus-invariant images from multiple views of single cells. Although the depth of field of the objective is short, it can be extended by scanning the objective's focal plane. This extended depth of field image is similar to a projection in conventional X-ray CT. Samples flow through a microcapillary tube filled with optical gel. Optical distortion is minimized by matching refractive index of optical gel and tube. Multiple projection images are taken by rotating the microcapillary tube with sub-micron mechanical precision. After these pseudoprojection images are further aligned, computed tomography methods are then applied to the images to create a 3D reconstruction with isometric resolution of 0.35 microns. Three-dimensional reconstructed images of fluorescent microspheres and cells are shown.