gebhart/patrepeval huggingface dataset:
Synthesis, antiproliferative, and antiviral activity of certain 4-aminopyrrolo[2,3-d]pyridazine nucleosides: an entry into a novel series of adenosine analogs (1992)

The preparation of novel heterocyclic base modified adenosine analogues, the 4-aminopyrrolo[2,3-d]pyridazine nucleosides, is described. Crucial to their successful preparation was the use of the pyrrole glycoside intermediates 3-cyano-2-formyl-1-(2,3,5-tri-O-benzyl-beta-D-ribofuranosyl)pyrrole (11) and 3-cyano-2-formyl-1-(2,3,5-tri-O-benzyl-beta-D-arabinofuranosyl)pyrrole (17). Treatment of 11 and 17 with hydrazine dihydrochloride followed by treatment with boron trichloride provided 4-amino-1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazine (2) and 4-amino-1-beta-D-arabinofuranosylpyrrolo[2,3-d]pyridazine (3), respectively. 4-Amino-3-bromo-1-beta-D-ribofuranosylpyrrolo[2,3-d]-pyridazine (4) was prepared by a bromination of 4-amino-1-(2,3,5-tri-O-benzyl-beta-D-ribofuranosyl)pyrrolo[2,3-d]pyri daz ine (12) and subsequent removal of the benzyl groups with boron trichloride. Compounds 2-4 were evaluated for antiproliferative and antiviral activity. The tubercidin analogue (2) and its arabinosyl derivative (3) were virtually inactive in all assays. In contrast, the 3-bromo analogue 4 inhibited growth of L1210 and H. Ep. 2 cells. Compound 4 was also active against human cytomegalovirus and herpes simplex virus type 1, but the antiviral activity was not completely separated from cytotoxicity.
Mechanical reliability, thermal stability and thermoelectric performance of the transition-metal nitride CrN (2020)

The mechanical reliability and thermal stability of thermoelectric materials are often the most neglected, while they will greatly affect the reliability and performance of thermoelectric devices when used in extreme environments. In this study, a nanostructured chromium nitride (CrN) thermoelectric material with a ZT value ∼0.12, exhibiting both high mechanical reliability and thermal stability, was prepared using a simple chemical method. Its hardness, reaching 7.21 GPa, is much higher than that of most other traditional thermoelectric materials. Thermogravimetric analysis shows that CrN remains stable at 873 K. Moreover, friction and wear tests demonstrate the high wear resistance and low friction coefficient (∼0.42) of CrN. The high thermal stability and good mechanical properties are expected to offer a wide range of opportunities for the thermoelectric application of CrN in some extreme environments, such as collision avoidance systems and outer space.
Planar catadioptric stereo: geometry and calibration (2003)

By using mirror reflections of a scene, stereo images can be captured with a single camera (catadioptric stereo). Single camera stereo provides both geometric and radiometric advantages over traditional two camera stereo. In this paper we discuss the geometry and calibration of catadioptric stereo with two planar mirrors and show how the relative orientation, the epipolar geometry and the estimation of the focal length are constrained by planar motion. In addition, we have implemented a real-time system which demonstrates the viability of stereo with mirrors as an alternative to traditional two camera stereo.
Electrochemical Separation of Hydrogen Sulfide from Natural Gas (1990)

Abstract An electrochemical process has been developed for the removal of H2S from contaminated natural gas. Removals as high as 80.7% have been achieved from a simulated process gas (2000 ppm H2S). H2S is removed by reduction to the sulfide ion and hydrogen gas at the cathode. The sulfide ion migrates to the anode through a molten electrolyte suspended in an inert ceramic matrix. Once at the anode it is oxidized to elemental sulfur and swept away for condensation in an inert gas stream. No materials are required beyond initial electrolyte membrane installation; the H2S is converted in one step to elemental sulfur making it an economically attractive process both from the lack of raw materials and the lack of any solvent regeneration.
Rigid, Specific, and Discrete Gold Nanoparticle/Antibody Conjugates (2006)

A general method of rigid, specific labeling of proteins with gold clusters has been devised. The method relies on the conjugation of a glutathione monolayer-protected gold cluster (MPC) with a single chain Fv antibody fragment (scFv), mutated to present an exposed cysteine residue. Efficient formation of a gold−thiolate bond between the MPC and scFv depends on activation of the gold cluster by chemical oxidation. Once formed, the MPC−scFv conjugate is treated with a reductant to quench cluster reactivity. The procedure has been performed with an MPC with an average Au71 core and an scFv directed against a tetrameric protein, the influenza neuraminidase. A complex of the MPC−scFv conjugate with the neuraminidase was isolated, and the presence of four gold clusters was verified by cryoelectron microscopy.
<i>Bacillus thuringiensis</i> §-Endotoxin Expressed in Transgenic <i>Nicotiana tabacum</i> Provides Resistance to Lepidopteran Insects (1987)

The crystal proteins, or section sign-endotoxins, of Bacillus thuringiensis are specifically lethal to Lepidopteran insects. We utilized a truncated and modified portion of a cloned crystal protein gene to construct a chimeric gene capable of expression in plant cells. Using an Agrobacterium tumefaciens binary vector system, we then transferred the chimeric toxin gene into tobacco (Nicotiana tabacum cv Havana 425) cells and regenerated recombinant plants. One to several copies per cell of the toxin gene are routinely present in the recombinant plants. Hybridization experiments demonstrated that these plants had a new RNA species of the size expected for the truncated toxin mRNA, and a polypeptide having the mobility expected for the truncated toxin was detected by immunoblotting. Significant variation was found in the levels of toxin-specific RNA expression between different recombinants, but the levels of hybridizing RNA in transformants correlated with the level of toxicity demonstrated against Manduca sexta (tobacco hornworm), and other Lepidopteran insects. The recombinant genes were transmitted to progeny and resistance to insects was maintained, thus demonstrating that the introduction of toxin genes into plants may be a practical method of providing protection against certain insect pests.
A Ligand-Directed Approach to Activity-Based Sensing: Developing Palladacycle Fluorescent Probes that Enable Endogenous Carbon Monoxide Detection (2020)

Carbon monoxide (CO) is an emerging gasotransmitter and reactive carbon species with broad anti-inflammatory, cytoprotective, and neurotransmitter functions along with therapeutic potential for the treatment of cardiovascular diseases. The study of CO chemistry in biology and medicine relative to other prominent gasotransmitters such as NO and H2S remains challenging, in large part due to limitations in available tools for the direct visualization of this transient and freely diffusing small molecule in complex living systems. Here we report a ligand-directed activity-based sensing (ABS) approach to CO detection through palladium-mediated carbonylation chemistry. Specifically, the design and synthesis of a series of ABS probes with systematic alterations in the palladium-ligand environment (e.g., sp3-S, sp3-N, sp2-N) establish structureactivity relationships for palladacycles to confer selective reactivity with CO under physiological conditions. These fundamental studies led to the development of an optimized probe, termed Carbon Monoxide Probe-3 Ester Pyridine (COP3E-Py), which enables imaging of CO release in live cell and brain settings, including monitoring of endogenous CO production that triggers presynaptic dopamine release in fly brains. This work provides a unique tool for studying CO in living systems and establishes the utility of a synthetic methods approach to activity-based sensing using principles of organometallic chemistry
Continuous On-Line Measurement of Lignin Concentration in Wood Pulp (2010)

We are working toward the development of an instrument for the continuous, on-line measurement of the lignin concentration in wood pulp. The instrument is based on laser induced fluorescence of the wood pulp and is to be used as a primary sensor for both feedback control of the pulping and feedforward control of bleaching. We report here the results of a series of laboratory tests that characterized the fluorescence properties of wood pulp and demonstrated a correlation between various fluorescence functions and the Kappa number of the pulps as determined by TAPPI Procedure T236.
Conjugated linoleic acid and the control of cancer and obesity (1999)

The effects of conjugated linoleic acid (CLA) in animals are reviewed. In most of the CLA preparations that have been investigated to date for biological activity, two CLA isomers are present in about equal concentrations: cis-9,trans-11 CLA, and trans-10,cis-12 CLA. The occurrence of these isomers in foods and their production by rumen microorganisms are discussed. Potential mechanisms of action as regards the effects of CLA on cancer and body composition are reviewed, including recent evidence that body composition changes are produced by the trans-10,cis-12 CLA isomer. Evidence is presented indicating that CLA may modulate cellular response to tumor necrosis factor-alpha (TNF-alpha). The mechanistic implications of this finding are considered.
Dynamic Plasmonic Pixels (2018)

We demonstrate spectral, spatial, and temporal control of plasmonically generated color through alignment of Au nanorods by an applied electric field. Tailoring the nanorod aspect ratio enables operation across the visible and near-infrared spectrum.
Microwave-enhanced infrared thermography (1998)

No single sensor modality will solve the problem of detecting small, buried objects in soil in the presence of typical clutter. Techniques involving fusion of data from multiple sensors can improve detection statistics. At the next level of complexity is multi-modal sensing in which an excitation with one modality is detected by another. Here we consider one such example, microwave heating of the soil followed by infrared imaging. The technique promises to produce signatures of buried objects which have contrast with respect to the surrounding soil in (1) absorption at the microwave frequency resulting in a change in the amount of energy absorbed, (2) dielectric constant resulting in alteration of the field distribution in the soil, or (3) thermal properties resulting in changes in the heat distribution. Indirect detection may be possible, through changes in the microwave or thermal properties of the soil caused by disturbance during placement of the object, or caused by changes in the soil properties resulting from alterations in water content caused by the object. We discuss wavelength selection, expected sensitivity, and techniques for enhancement of the signal, as well as overall system requirements, and will show some preliminary results.
Detecting cracks in teeth using ultrasonic excitation and infrared imaging (2001)

We describe a new technique, Thermosonics, that can be used to detect cracks in teeth. This technique was initially invented and developed for finding cracks in industrial and aerospace applications. The thermosonics technique employs a single short pulse (typically tens of milliseconds) of ultrasound excitation combined with infrared imaging. Ultrasonic waves vibrate the target material. This vibration causes rubbing and clapping between faying surfaces of any cracks which are present, resulting in a temperature rise around the cracks. An infrared camera is used to image the temperature distribution during and after the ultrasound excitation. Thus, cracks in teeth can be detected. Although this technique is still under development, it shows promise for clinical use by dentists.
On the write energy of non-volatile resistive crossbar arrays with selectors (2018)

Crossbar arrays based on non-volatile resistive devices such as resistive RAM and phase change memory have become an important technology due to the applications to memory systems. The energy consumption of integrated circuits has become a primary issue due to thermal constraints in high performance systems and limited battery time in mobile and IoT applications. In this paper, the energy efficiency of a crossbar array of a one-selector-one-resistor (1S1R) configuration during a write operation is explored for the V/2 and V/3 bias schemes. The characteristics that affect the most energy efficient bias scheme are demystified. The write energy of a crossbar array is modeled in terms of the array size, number of selected cells, and the nonlinearity factor. For a specific array size and selector technology, the number of selected cells during a write operation can affect the choice of bias scheme. Moreover, the effect of leakage current due to partially biased unselected cells is explored.
Active CMOS Array Sensor for Time-Resolved Fluorescence Detection (2006)

Surface-based sensing assays based on fluorescence-based detection have become commonplace for both environmental and biomedical diagnostics. Traditional array scanners are expensive, large, and complex instruments. This paper describes the design of an active CMOS biosensor substrate for fluorescence-based assays that enables time-gated, time-resolved fluorescence spectroscopy without the need for an external reader. The array is sensitive to photon densities as low as 1.15times10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> /cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , has a dynamic range of over 74 dB, and has subnanosecond timing resolution. Sensitivity is achieved through subsampling and averaging
Studies of acoustic-electric feed-throughs for power transmission through structures (2006)

There are numerous engineering design problems where the use of wires to transfer power and communicate data thru the walls of a structure is prohibitive or significantly difficult that it may require a complex design. Using physical feedthroughs in such systems may make them susceptible to leakage of chemicals or gasses, loss of pressure or vacuum, as well as difficulties in providing adequate thermal or electrical insulation. Moreover, feeding wires thru a wall of a structure reduces the strength of the structure and makes the structure prone to cracking due to fatigue that can result from cyclic loading and stress concentrations. One area that has already been identified to require a wireless alternative to electrical feedthroughs would be the container of any Mars Sample Return Mission, which would need wireless sensors to sense a pressure leak and to avoid potential contamination. The idea of using elastic or acoustic waves to transfer power was suggested recently by [Y. Hu, et al., July 2003]. This system allows for the avoidance of cabling or wiring. The technology is applicable to the transfer of power for actuation, sensing and other tasks inside any sealed container or vacuum/pressure vessel. An alternative approach to the modeling presented previously [Sherrit et al., 2005] used network analysis to solve the same problem in a clear and expandable manner. Experimental tests on three different designs of these devices were performed. The three designs used different methods of coupling the piezoelectric element to the wall. In the first test the piezoelectric material was bolted using a backing structure. In the second test the piezoelectric was clamped after the application of grease. Finally the piezoelectric element was attached using a conductive epoxy. The mechanical clamp with grease produced the highest measured efficiency of 53% however this design was the least practical from a fabrication viewpoint. The power transfer efficiency of conductive epoxy joint was 40% and the stress bolts (12%). The experimental results on a variety of designs will be presented and the thermal and non-linear issues will be discussed.
A Low Overhead, Within-a-Cycle Adaptive Clock Stretching Circuit With Wide Operating Range in 40-nm CMOS (2017)

Adaptive voltage frequency scaling (AVFS) techniques based on in-situ timing monitoring can mitigate the excessive timing margin caused by process, voltage and temperature (PVT) variations. However, they usually adjust the frequency by clock gating, clock half-division, or phase locked loop configuration, which cause large performance loss or need a long lock time. Thus, a compact structured adaptive clock stretching circuit is proposed here for very rapid frequency adjustment. It is very useful for AVFS systems by stretching the clock cycle with only within-a-cycle response time. The proposed architecture generates multi-phase clocks through a series of delay elements and continuously picks an appropriate phase clock to form a stretched clock. It also uses a process voltage temperature monitor to adjust the phase clock selection and makes this circuit suitable under PVT variations. Fabricated in 40-nm CMOS process, it only occupies a core area of 85* <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$83~{\mu }\text{m}^{2}$ </tex-math></inline-formula> . Measurements show that it can stretch the clock cycle immediately upon the stretch signal with within-a-cycle response time. It has a wide voltage range from 0.43 V to 1.1 V, with power consumptions of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$38.2~{\mu }\text{W}$ </tex-math></inline-formula> at 0.43 V/10 MHz and 4.55 mW at 1.1 V/1.2 GHz. Plus, it can provide configurable stretch amounts for the AVFS system. Thus, it can provide a within-a-cycle, low overhead frequency adjustment solution for AVFS systems.
Adaptive adjustment of receiver for distorted digital signals (1984)

The paper presents the results of an initial feasibility study into a novel technique for the adaptive adjustment of the receiver in a digital data-transmission system, operating with additive noise and severe inter-symbol interference in the received signal. The technique is an iterative process and can be used for the adjustment of the linear feedforward transversal filter that is employed ahead of a near-maximum-likelihood detector, and at the same time for the estimation of the sampled impulse response of the channel and filter, to give the information on the received signal needed by the detector. The latter two operations are equivalent to the adjustment of the feedforward and feedback transversal filters, respectively, in the corresponding nonlinear (decision-feedback)equaliser. The equaliser is, of course, a degenerate form of a near-maximum-likelihood detector, being obtained when the latter is reduced to its simplest possible form. The adaptive system operates directly on the estimate of the sampled impulse response of the channel, that must be provided at the receiver, and it requires no other input signals. It employs a root-finding algorithm that determines some of the roots (zeros) of the z-transform of the sampled impulse response of the channel. It then uses a knowledge of these roots to determine the tap gains of the linear feedforward transversal filter and to form an estimate of the sampled impulse response of the channel and filter. The technique can exploit the high tolerance to signal distortion of a near-maximum-likelihood detector in order to reduce the amount of processing of the received signal that is carried out by the adaptive filter to a level appreciably below that required by a conventional nonlinear equaliser. Thus a more cost-effective design of the receiver can be obtained. The paper describes the method of operation of two versions of the adaptive system and presents the results of computer-simulation tests over four different channels, showing both the rate and accuracy of convergence of the iterative process in each case.
Using latent class analysis to model prescription medications in the measurement of falling among a community elderly population (2013)

In conclusion the LCA method was effective at finding relevant subgroups within a heterogenous at-risk population for falling. This study demonstrated that LCA offers researchers a valuable tool to model medical data.
The Bin Area Method: A Computationally Efficient Technique for Analysis of Ventricular and Atrial Intracardiac Electrograms (1990)

Recent studies have reported a significant false positive rate in delivery of therapy by implantable antitachycardia devices utilizing detection algorithms based on sustained high rate. More selective decision schemes for the recognition of life-threatening arrhythmias have been recently proposed that use analysis of the intrinsic electrogram rather than rate alone. Morphological discrimination of abnormal electrograms using correlation waveform analysis (CWA) has been proposed as an effective method of intracardiac electrogram analysis, but its computational demands limit its use in implantable devices. A new method for intracardiac electrogram analysis, the bin area method (BAM), was created to detect abnormal cardiac conduction with computational requirements of one-half to one-tenth those of CWA. Like CWA, BAM is a template matching method that is sensitive to conduction changes revealed in the electrogram morphology and is independent of amplitude and baseline fluctuations. Performance of BAM and CWA were compared using bipolar right ventricular and right atrial electrode recordings from 47 patients undergoing clinical cardiac electrophysiology studies. Nineteen patients had 31 distinct monomorphic ventricular tachycardias (VTs) induced (group I), thirteen patients had paroxysmal bundle branch block of supraventricular origin (BBB) induced (group II), and 19 patients had retrograde atrial activation during right ventricular overdrive pacing (group III). (One patient was common to all three groups, and two patients were common to groups II and III.) Using the ventricular electrogram, both BAM and CWA distinguished VT from sinus rhythm in 28/31 (90%) cases, and BBB from Normal Sinus Rhythm (NSR) in 13/13 (100%) patients. Using the atrial electrogram, both BAM and CWA distinguished anterograde from retrograde atrial activation in 19/19 (100%) patients. BAM achieves similar performance to CWA with significantly reduced computational demands, and may make real-time analysis of intracardiac electrograms feasible for implantable pacemakers and antitachycardia devices.
The potential protective immune responses to synthetic peptides containing conserved epitopes of Porphyromonas gingivalis fimbrial protein (1994)

The immunodominant and T-cell epitopes within the fimbrial subunit protein (fimbrilin) of Porphyromonas gingivalis strain 381 were analysed by multi-pin peptide synthesis technology. Six regions with immunodominant epitopes within a sequence of 337 amino acids that reacted with the serum of patients with adult periodontitis were detected. T cells from mice immunised with P. gingivalis fimbriae exhibited proliferative responses to P. gingivalis fimbriae or to six 10-mer synthetic peptides from the amino-acid sequence of the fimbrillin. Three synthetic peptides that contained the regions responsible for the immunodominant epitopes as well as those which coincided with a T-cell epitope of P. gingivalis fimbrial molecules--FP38 (142-161), FP381(202-221) and FP381(216-243)--were selected and synthesised. When guinea-pigs were immunised with fimbriae or one of the three synthetic peptide segments and an adjuvant in Freund's incomplete adjuvant, enhanced production of the antigen-specific IgG antibodies was induced in the serum of the animals. Furthermore, of the three synthetic peptides tested, FP381(202-221) produced the greatest protective immune response in guinea-pigs infected with P. gingivalis and this was more effective than the native fimbrial protein.