gebhart/patrepeval huggingface dataset:
Synthesis and Physical Properties of Highly Sulfonated Polyaniline (1996)

Sulfonated polyaniline (SPAN) is a self-doped conducting polymer. It has a high water solubility and a novel pH-dependent DC conductivity that is of interest for fundamental science and also for applications in such areas as rechargeable battery and pH control technologies. We report here the extensive characterization and details of synthesis of a new form of sulfonated polyaniline (LEB-SPAN) which shows novel or significantly improved chemical and physical properties. LEB-SPAN has a high sulfur to nitrogen ratio (S/N) of ∼0.75, 50% larger than that previously reported for EB-SPAN, S/N ∼0.50. This change in composition leads to significant alteration of the properties including an order of magnitude increase in the room temperature DC conductivity to ∼1 S·cm-1, nearly double the solubility in water, and a completely different pH dependence of the oxidation potential (E1/2). For LEB-SPAN the DC conductivity is unaffected by pH over the range 0 ≤ pH ≤ 14, strikingly different from the behavior of both parent polyaniline and EB-SPAN which become insulating for pH ≥3 and ≥7.5, respectively. Temperature-dependent DC conductivity and EPR measurements for LEB-SPAN reveal a lower activation energy for the conductivity and a higher density of states at the Fermi energy as compared with EB-SPAN. The dramatic differences in the pH dependence of the DC conductivity, cyclic voltammetry (CV), FTIR, and UV−vis results for LEB-SPAN and EB-SPAN are shown to be a consequence of the much higher S/N ratio in LEB-SPAN. We propose and describe a novel quasi-random oxidation model for the electrochemical oxidation of polyaniline and its derivatives at the microscopic level. This model quantitatively describes many of the phenomena and physical properties found in the polyanilines including the origin of the defect states and the in situ EPR signal during CV potential scans. Also the statistical nature of this model suggests its general applicability to the oxidation process of other conducting polymers. Computer simulations based on this model are presented and show good agreement with the in situ EPR/CV data reported earlier. In addition, other models are proposed to interpret the reported experimental differences in the pH dependence of E1/2 among LEB-SPAN, EB-SPAN, and its parent polyaniline samples. Mechanisms for the new sulfonation route are proposed.
Internal magnetostriction observed by X-ray diffraction in iron (2005)

A new technique to observe the internal mode of the magnetostriction with sufficient sensitivity using X-ray diffraction was developed. As a result, the antisymmetry part of the diffraction intensity change was proportional to a flipping ratio of an X-ray magnetic diffraction (XMD). This technique using X-rays has the potential to simultaneously investigate magnetostriction together with XMD at local coextensive specimen volumes.
An Empirical Model for Specularity Prediction with Application to Dynamic Retexturing (2016)

Specularities, which are often visible in images, may be problematic in computer vision since they depend on parameters which are difficult to estimate in practice. We present an empirical model called JOLIMAS: JOint LIght-MAterial Specularity, which allows specularity prediction. JOLIMAS is reconstructed from images of specular reflections observed on a planar surface and implicitly includes light and material properties which are intrinsic to specularities. This work was motivated by the observation that specularities have a conic shape on planar surfaces. A theoretical study on the well known illumination models of Phong and Blinn-Phong was conducted to support the accuracy of this hypothesis. A conic shape is obtained by projecting a quadric on a planar surface. We showed empirically the existence of a fixed quadric whose perspective projection fits the conic shaped specularity in the associated image. JOLIMAS predicts the complex phenomenon of specularity using a simple geometric approach with static parameters on the object material and on the light source shape. It is adapted to indoor light sources such as light bulbs or fluorescent lamps. The performance of the prediction was convincing on synthetic and real sequences. Additionally, we used the specularity prediction for dynamic retexturing and obtained convincing rendering results. Further results are presented as supplementary material.
Thermoacoustic tomography using integrating detectors (2005)

Thermoacoustic (optoacoustic, photoacoustic) tomography is an emerging technology for imaging semitransparent objects, like soft biological tissue. Thermoacoustics combines the advantages of pure optical imaging with those of ultrasound imaging. In optical imaging the contrast is usually high, but the image resolution is poor because of the diffuse nature of light propagation. In ultrasonic imaging, the contrast between structures with similar acoustic properties (e.g. different soft tissue constituents) is low, but the spatial resolution is high because of the relatively unhindered propagation of ultrasonic waves. Due to the conversion of absorbed electromagnetic radiation into sound waves, thermoacoustics is able to generate images that at the same time have optical contrast and ultrasonic resolution. A novel measurement setup using integrating detectors is proposed and demonstrated by reconstructing the cross section of a grape. The use of integrating detectors to obtain time-retarded projections of optical absorption along surfaces parallel to the detector surface is quite different to current approaches and has important advantages. It avoids the problem of piezoelectric detectors to obtain adequate detection sensitivity when using the acoustically small element sizes required for "conventional" imaging reconstruction algorithms. Another advantage is that the reconstruction can be achieved via the inverse Radon Transform. Thus, many of the existing reconstruction methods (e.g. those using sparse data sets) developed for computerized tomography are directly applicable enabling the progress in this area to be rapid and integrating detectors may become widely adopted.
Compatibilized and dynamically vulcanized thermoplastic elastomer blends of poly(butylene terephthalate) and ethylene propylene diene rubber (1992)

Abstract Compatibilized and dynamically vulcanized thermoplastic elastomer blends of poly(butylene terephthalate) (PBT) and ethylene propylene diene terpolymer (EPDM) can be prepared by using an EPDM rubber that contains reactive epoxy groups. During melt mixing the epoxy groups react with PBT endgroups to form graft copolymer. The compatibilized blends can be dynamically vulcanized by conventional vulcanization agents for EPDM such as peroxides or by vulcanization agents that react with residual epoxy groups on the EPDM such as diamines. This paper describes the effects of compatibilization and dynamic vulcanization on microstructure and mechanical properties.
A hybrid algorithm for randoms variance reduction (2009)

We describe a new algorithm for randoms variance reduction in positron emission tomography (PET) that makes use of both delayed coincidence data and separately measured, coarsely sampled, detector singles event rates. The algorithm has been tested on 2D data for several phantom studies. We find that it gives randoms estimates nearly as precise as a fan-sum algorithm, but with low bias. The amount of bias depends on how accurately the singles data represents the actual structure of the singles. With 12 samples per detector ring on a clinical PET scanner, maximum local bias for a clinically realistic phantom is ±2%, but can be twice this much for highly asymmetric objects.
A novel one transistor resistance-gate nonvolatile memory (2016)

For the first time, we propose a one transistor resistance-gate nonvolatile memory (RG-NVM) which comprises a simple MIM structure on top of the transistor gate while readout is taken from the transistor V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> or I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> , similar to that of flash memory. A bilayer MIM is preferable for quality performance. The program/erase operation of the memory is made by the edge-tunneling between source/drain and the top gate. Results demonstrated that this memory exhibits good endurance, retention, and can solve the sneak path issues of conventional crossbar ReRAM.
Azimuthal Fourier Coefficient Elastic Inversion (2012)

Summary The benefits of using azimuthal Fourier Coefficients to estimate fracture properties has been proven theoretically and illustrated on real dataset. The 2 nd Fourier Coefficient provides a biased estimate of the anisotropic gradient but using a combination of Fourier Coefficients removes that bias, along with estimating an unambiguous symmetry axis. The azimuthal elastic inversion can be modified to invert Fourier Coefficients rather than azimuthal angle stacks in order to estimate fracture parameters. The main advantage of using this alternative data space is to reduce the cross-talk between the fracture and isotropic background parameters. For quality control purpose, the results obtained from the azimuthal elastic inversion can be easily transformed to the anisotropic gradient for comparison with other methods such as the near offset Ruger equation or other reflectivity approaches and these comparisons are illustrated on real dataset. The azimuthal elastic inversion provides layer properties that are easier to relate to the geology than interface properties.
Novel, electrolyte solutions comprising fully inorganic salts with high anodic stability for rechargeable magnesium batteries (2013)

Herein the first inorganic magnesium salt solution capable of highly reversible magnesium electrodeposition is presented. Synthesized by acid-base reaction of MgCl2 and Lewis acidic compounds such as AlCl3, this salt class demonstrates upwards of 99% Coulombic efficiency, deposition overpotential of <200 mV, and anodic stability of 3.1 V.
Motion camera based on a custom vision sensor and an FPGA architecture (1998)

A digital camera for custom focal plane arrays was developed. The camera allows the test and development of analog or mixed-mode arrays for focal plane processing. The camera is used with a custom sensor for motion detection to implement a motion computation system. The custom focal plane sensor detects moving edges at the pixel level using analog VLSI techniques. The sensor communicates motion events using the event-address protocol associated to a temporal reference. In a second stage, a coprocessing architecture based on a field programmable gate array (FPGA) computes the time-of-travel between adjacent pixels. The FPGA allows rapid prototyping and flexible architecture development. Furthermore, the FPGA interfaces the sensor to a compact PC computer which is used for high level control and data communication to the local network. The camera could be used in applications such as self-guided vehicles, mobile robotics and smart surveillance systems. The programmability of the FPGA allows the exploration of further signal processing like spatial edge detection or image segmentation tasks. The article details the motion algorithm, the sensor architecture, the use of the event- address protocol for velocity vector computation and the FPGA architecture used in the motion camera system.
Feasibility and Challenge of Quantitative Cement Evaluation with LWD Sonic (2013)

Abstract Cementing is an essential part of well construction as it supports the casing and provides hydraulic sealing. Quantitative cement evaluation is becoming increasingly important in the industry to verify well integrity and zonal isolation. Such information has historically been obtained with a wireline tool, acquiring data at ultrasonic or sonic frequencies. The most common log providing information on cement bond quality is the cement bond log (CBL), which relies on the amplitude of the casing arrival to determine the quality of cement bonding to the casing and in some applications to the formation. Although logging while drilling (LWD) sonic technology has progressed rapidly in recent years the established service from an LWD sonic tool that provides cement information is only top of cement (TOC), and it indicates only the presence or absence of cement behind the casing. Since the major structural part of the tool is a rigid steel collar, there is significant acoustic propagation along the collar. It is technically difficult to separate the casing signal from the one traveling in the collar as these two propagations have similar speed and frequency content. When the cement is poorly bonded to the casing, the casing amplitude can be far larger than the collar arrival. However, if the cement is well-bonded, most of the casing signal energy is dissipated into the cement, and the casing amplitude at a receiver a certain distance from the transmitter tends to be similar or even smaller than the collar arrival. In such cases, the measured signal loses sensitivity to cement bonding. However, it is challenging to establish a relationship between the respective amplitudes of the collar and casing as it depends upon many factors such as the acoustic impedance of the cement and the casing size. We explore the feasibility of quantitative cement evaluation with a conventional LWD sonic tool. Finite-difference method (FDM) modeling over a wide range of conditions was conducted to quantify the relationship between casing amplitude and collar arrival. Results indicate that quantitative cement evaluation is feasible with existing LWD sonic tools, depending upon the bonding value. This study also provided information for comparisons between conventional wireline cement evaluation methods and LWD-derived CBL.
Synthesis of 13‐(Substituted benzyl) Berberine and Berberrubine Derivatives as Antifungal Agents. (2006)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Azatoxin Is a Mechanistic Hybrid of the Topoisomerase II-Targeted Anticancer Drugs Etoposide and Ellipticine (1997)

One approach to broadening the diversity of topoisomerase II-targeted anticancer agents is to generate novel compounds by combining structural elements of drugs known to stimulate enzyme-mediated DNA cleavage. The first agent to emerge from such a rational drug design is azatoxin, a hybrid drug that fuses chemical structures from etoposide and ellipticine. Since these drugs differ significantly in their structural and mechanistic attributes, azatoxin may preferentially retain the functional properties of one of these two drugs, behave as a hybrid molecule, or act as a novel pharmacophore. Therefore, the properties of azatoxin were characterized to determine relationships between its mechanism of action and those of its parent compounds. Azatoxin, like etoposide, binds to DNA in a nonintercalative fashion. However, similar to ellipticine, the drug has no effect on enzyme-mediated DNA religation and apparently stimulates scission primarily by enhancing cleavage complex formation. Depending on the species of topoisomerase II examined, the cleavage potency of azatoxin resembles that of either of its chemical parents. Furthermore, out of 43 DNA cleavage sites analyzed, approximately 90% of those induced by azatoxin are shared with either etoposide, ellipticine, or both drugs. Finally, competition studies indicate that azatoxin interacts with topoisomerase II in the enzyme domain utilized by etoposide and ellipticine. Taken together, these results strongly suggest that azatoxin is a mechanistic hybrid of its parent compounds and shares functional properties with both drugs.
Hierarchical Clustering using Auto-encoded Compact Representation for Time-series Analysis (2021)

Getting a robust time-series clustering with best choice of distance measure and appropriate representation is always a challenge. We propose a novel mechanism to identify the clusters combining learned compact representation of time-series, Auto Encoded Compact Sequence (AECS) and hierarchical clustering approach. Proposed algorithm aims to address the large computing time issue of hierarchical clustering as learned latent representation AECS has a length much less than the original length of time-series and at the same time want to enhance its performance.Our algorithm exploits Recurrent Neural Network (RNN) based under complete Sequence to Sequence(seq2seq) autoencoder and agglomerative hierarchical clustering with a choice of best distance measure to recommend the best clustering. Our scheme selects the best distance measure and corresponding clustering for both univariate and multivariate time-series. We have experimented with real-world time-series from UCR and UCI archive taken from diverse application domains like health, smart-city, manufacturing etc. Experimental results show that proposed method not only produce close to benchmark results but also in some cases outperform the benchmark.
Development of a Novel Wireless Multi-Channel Stethograph System for Monitoring Cardiovascular and Cardiopulmonary Diseases (2021)

Abstract A multi-channel stethograph system was designed and developed as an electronic auscultation system for graphic recording of heart, lung and trachea (HLT) sounds non-invasively through a set of 16 acoustic sensors. The multi-channel stethograph system was fabricated by placing 16 microphone based acoustic sensor in a CNC machined Delrin® housing cases that are covered using diaphragms. Among the 16 acoustic sensors, 14 were positioned in a memory foam pad and 2 were placed directly on the heart and trachea to acquire sounds simultaneously from the lungs, heart and trachea. The sounds acquired from the 16 acoustic sensors were processed through a custom designed and fabricated 16-channel PCB for signal conditioning. A National Instruments (NI) 9205 data acquisition device (DAQ) along with a NI 9191 wireless chassis was used to acquire and wirelessly transmit the data from the 16-channel PCB to a Wi-Fi enabled device such as a PC/tablet. A custom LabVIEW program was developed on a Wi-Fi enabled PC/tablet to record the data from the DAQ. In addition, a MATLAB program was developed to convert the recorded data from the acoustic sensors into 16 audio files (for audio playback) and plot the waveforms in time and frequency domain as well as spectrogram for visual examination of any abnormal patterns in inhalation and exhalation. This provides critical information on the presence of wheezes, crackles and rhonchi sounds as well as abnormal heartbeat and respiration rate which helps in analyzing the condition of heart and lungs. The graphically displayed HLT sounds will help physicians in the clinical diagnosis and monitoring of lung and heart disorders, particularly chronic obstructive pulmonary disease (COPD), asthma, pneumonia, and congestive heart failure by providing objective evidence.
A Multiparty Videoconferencing System Over an Application-Level Multicast Protocol (2007)

Increased speeds of PCs and networks have made media communications possible on the Internet. Today, the need for desktop videoconferencing is experiencing robust growth in both business and consumer markets. However, the synchronous delivery of high-volume media content is still a big challenge under a current heterogeneous Internet environment. In this paper, we present a multiparty videoconferencing system based on a peer-to-peer (P2P) solution. The contribution of our paper is twofold. On the one hand, we design an application-level multicast scheme which intends to tolerate the heterogeneity in videoconferencing applications. Design tradeoffs are analyzed and our decisions are made based on extensive experimentation. On the other, we design a five-layer architecture for implementing a multiparty videoconferencing system. This architecture makes a clear-cut distinction between different functional modules and therefore provides rich flexibility in feature adaptation. We believe that our work can be a helpful reference in other efforts on building desktop videoconferencing systems.
An Artificial Neuron Founded on Resistive Switching of Mott Insulators (2017)

Narrow-gap Mott insulators exhibit under electric field a resistive switching related to the formation of a conducting filamentary path made of metastable metallic domains. When this effect is non-volatile it can be used to build up a new type of Resistive Random Access Memory called Mott memory. But we show here that when the resistive switching remains volatile it is of great interest for neuromorphic applications different than artificial synapses implemented by the so-called Memristors. Specifically, we show that under electric field the dynamics of the creation and destruction of the metastable metallic domains implement the three basic functions Leaky Integrate and Fire of artificial neurons. The central result of the present work is therefore to demonstrate that a simple two terminal device made of Mott insulator can be considered as an analogue of an artificial Leaky Integrate and Fire neuron.
44.2: Super‐High‐Resolution FLC Display Based on Field Sequential Color Method with Low Driving Voltage (2003)

Abstract We investigated the effect of a storage capacitor (Cs) on the driving voltage in ferroelectric liquid crystal (FLC) displays by which a TFT array drives the FLCs. The addition of Cs enabled a decrease in the driving voltage. When spontaneous polarization (Ps) was large, the decrease in the driving voltage was larger than when Ps was small. We were able to use 5V as the driving voltage of an FLC display. According to the prototype we built based on the field sequential color (FSC) method, we were able to achieve the characteristics of super‐high‐resolution (318 ppi), high‐speed response (300 μs), and high color purity (greater than the NTSC standard).
A Very Simple, Highly Stereoselective and Modular Synthesis of Ferrocene-Based P-Chiral Phosphine Ligands (2006)

A very simple, highly stereoselective and modular synthesis of ferrocene-based P-chiral phosphine ligands has been developed. On the basis of this new methodology, several new families of ferrocene-based phosphine ligands have been prepared coupling chirality at phosphorus with other, more standard stereogenic features. The introduction of P-chirality into ferrocene-based phosphine ligands enhances the enantioselective discrimination produced by the corresponding Rh catalyst when a matching among the planar chirality, carbon chirality, and the chirality of phosphorus is achieved.
Segmentation and Probabilistic Registration of Articulated Body Models (2006)

There are different approaches to pose estimation and registration of different body parts using voxel data. We propose a general bottom-up approach in order to segment the voxels into different body parts. The voxels are first transformed into a high dimensional space which is the eigenspace of the Laplacian of the neighbourhood graph. We exploit the properties of this transformation and fit splines to the voxels belonging to different body segments in eigenspace. The boundary of the splines is determined by examination of the error in spline fitting. We then use a probabilistic approach to register the segmented body segments by utilizing their connectivity and prior knowledge of the general structure of the subjects. We present results on real data, containing both simple and complex poses. While we use human subjects in our experiment, the method is fairly general and can be applied to voxel-based registration of any articulated or non-rigid object composed of primarily 1-D parts