gebhart/patrepeval huggingface dataset:
A Semi-Digital Delay-Locked Loop Using an Analog-Based Finite State Machine (2004)

This brief describes a low-power full-rate semi-digital delay-locked loop (DLL) architecture using an analog-based finite state machine (AFSM) and a polyphase filter. The AFSM architecture uses low-power analog blocks to map high-frequency loop feedback information to low frequency, thus reducing the total power required for digital signal processing and for the macro as a whole. The polyphase filter generates full-rate multiphase outputs for a phase rotator, hence a reference clock of the semi-digital DLL can be generated by any reference source including a phase-locked loop with an LC voltage-controlled oscillator. The prototype semi-digital DLL in 0.12-/spl mu/m CMOS exhibits less than 10/sup -12/ bit error rate at 3.2 Gb/s consuming 60 mW.
Highly Enantioselective Azadiene Diels—Alder Reactions Catalyzed by Chiral N‐Heterocyclic Carbenes. (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.
Single-electron tunneling force spectroscopy of an individual electronic state in a nonconducting surface (2006)

A tunneling spectroscopy technique to measure the energy level of an electronic state in a completely nonconducting surface is demonstrated. Spectroscopy is performed by electrostatic force detection of single-electron tunneling between a scanning probe and the state as a function of an applied voltage. An electronic state near the surface of a SiO2 film is found 5.5±0.2eV below the conduction band edge. A random telegraph signal, caused by sporadic back-and-forth single-electron tunneling, is observed as the probe Fermi level passes through the state energy.
Transcytosis in the blood–cerebrospinal fluid barrier of the mouse brain with an engineered receptor/ligand system (2015)

Crossing the blood-brain and the blood-cerebrospinal fluid barriers (BCSFB) is one of the fundamental challenges in the development of new therapeutic molecules for brain disorders because these barriers prevent entry of most drugs from the blood into the brain. However, some large molecules, like the protein transferrin, cross these barriers using a specific receptor that transports them into the brain. Based on this mechanism, we engineered a receptor/ligand system to overcome the brain barriers by combining the human transferrin receptor with the cohesin domain from Clostridium thermocellum, and we tested the hybrid receptor in the choroid plexus of the mouse brain with a dockerin ligand. By expressing our receptor in choroidal ependymocytes, which are part of the BCSFB, we found that our systemically administrated ligand was able to bind to the receptor and accumulate in ependymocytes, where some of the ligand was transported from the blood side to the brain side.
Molecular Characterization of the Heparin-Dependent Transduction Domain on the Capsid of a Novel Adeno-Associated Virus Isolate, AAV(VR-942) (2008)

A new adeno-associated virus (AAV), referred to as AAV(VR-942), has been isolated as a contaminant of adenovirus strain simian virus 17. The sequence of the rep gene places it in the AAV serotype 2 (AAV2) complementation group, while the capsid is only 88% identical to that of AAV2. High-level AAV(VR-942) transduction activity requires cell surface heparan sulfate proteoglycans, although AAV(VR-942) lacks residues equivalent to the AAV2 R585 and R588 amino acid residues essential for mediating the interaction of AAV2 with the heparan sulfate proteoglycan receptor. Instead, AAV(VR-942) uses a distinct transduction region. This finding shows that distinct domains on different AAV isolates can be responsible for the same activities.
Bacteria Identification by Phage Induced Impedance Fluctuation Analysis (BIPIF) (2010)

We present a new method for detecting and identifying bacteria by measuring impedance fluctuations (impedance noise) caused by ion release by the bacteria during phage infestation. This new method significantly increases the measured signal strength and reduces the negative effects of drift, material aging, surface imperfections, 1/f potential fluctuations, thermal noise, and amplifier noise. Comparing BIPIF with another well-known method, bacteria detection by SEnsing of Phage Triggered Ion Cascades (SEPTIC), we find that the BIPIF algorithm is easier to implement, more stable and significantly more sensitive (by several orders of magnitude). We project that by using the BIPIF method detection of a single bacterium will be possible.
Measurement of end-systolic pressure-volume relations by intra-aortic balloon occlusion. (1989)

A new situ technique has been developed for measuring peak end-systolic elastance, Emax, that does not alter intrinsic or reflex-stimulated cardiac contractility. Afterload is varied by the inflation of an intra-aortic balloon catheter positioned in the ascending aorta. Balloon inflation is timed to interrupt ventricular ejection transiently at different times during the ejection phase, therefore, producing contraction at different ventricular volumes. Simultaneous measurement of left ventricular pressure and aortic flow during the occlusion sequence allows pressure versus ejected volume loops to be generated, from which the end-systolic pressure-volume relation is determined. End-systolic pressure-volume relation (ESPVR) was measured in six anesthetized Dorsett sheep with normal and enhanced contractile states. ESPVR was analyzed using both linear and nonlinear techniques. Although nonlinear components were seen in ESPVR, for the pressure-volume data range produced by the transient occlusions, linear approximations of ESPVR fit the end-systolic data points well. In the normal state, Emax, the slope of the linear ESPVR, was 1.01-5.08 mm Hg/ml in animals with body weights of 23-32 kg. After epinephrine infusion, Emax increased from 3.07 +/- 1.49 to 5.79 +/- 1.97 mm Hg/ml, which is consistent with previous investigations. Linear and nonlinear volume intercepts had a small increase with positive inotropic stimulation. Furthermore, serial measurements of Emax tracked cardiac function in depressed hearts with rapidly changing contractility.
Semisolid Casting of Magnesium Alloy AZ91D using Inclined Cooling Plate (2002)

To obtain an ingot of AZ91D magnesium alloy containing granular primary crystals of magnesium in the cast structure, we performed semisolid casting using an inclined cooling plate. In this casting process, molten metal is flown onto the inclined cooling plate to induce the primary magnesium crystal nucleation on the cooling plate. The molten metal containing the primary magnesium crystals which is flown onto the inclined cooling plate is cast in a preheated mold, where the crystals grow into grains. Factors which affect the cast structures are pouring temperature, the angle of the incline, and the length of the cooling plate. Under optimal conditions, an ingot of fine grains is obtained. Next, under optimal conditions of mold casting, we performed continuous casting along a horizontal direction, and we obtained a billet with a diameter of about 40 mm and a length of about 600 mm. All of the cast structures obtained were composed of fine grains.
Seebeck difference - temperature sensors integrated into smart power technologies (2009)

In this work, difference - temperature (ΔT) sensors based on the Seebeck effect integrated into a common drain smart power MOSFET technology are presented. The sensors generate a voltage signal proportional to the ΔT. The highest Seebeck coefficient measured was 0.92 mV/K. This result was achieved with a p - doped silicon and n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> - doped poly silicon Seebeck ΔT sensor. Power MOSFETs with embedded Seebeck ΔT sensors are, to our knowledge, demonstrated for the first time.
Word line pulsing technique for stability fault detection in sram cells (2006)

Stability testing of SRAMs has been time consuming. This paper presents a new programmable DFT technique for detection of stability and data retention faults in SRAM cells. The proposed technique offers extended flexibility in setting the weak overwrite test stress, which allows to track process changes without time-consuming post-silicon design iterations. Moreover, it does not introduce extra circuitry in the SRAM array and surpasses the data retention test in test time and detection capability
Using arrays of air-filled resonators to attenuate low frequency underwater sound (2014)

This paper investigates the acoustic behavior of underwater air-filled resonators that could potentially be used in an underwater noise abatement system. The resonators are similar to Helmholtz resonators without a neck, consisting of underwater inverted air-filled cavities with combinations of rigid and elastic wall members, and they are intended to be fastened to a framework to form a stationary array surrounding a noise source, such as a marine pile driving operation, a natural resource production platform, or an air gun array, or to protect a receiving area from outside noise. Previous work has demonstrated the potential of surrounding low frequency sound sources with arrays of large stationary encapsulated bubbles that can be designed to attenuate sound levels over any desired frequency band and with levels of reduction up to 50 dB [Lee and Wilson, Proceedings of Meeting on Acoustics 19, 075048 (2013)]. Open water measurements of underwater sound attenuation using resonators were obtained during a set of lake experiments, where a low-frequency electromechanical sound source was surrounded by different arrays of resonators. The results indicate that air-filled resonators are a potential alternative to using encapsulated bubbles for low frequency underwater noise mitigation. [Work supported by AdBm Technologies.]
Osmium-Catalyzed Dihydroxylation of Olefins Using Dioxygen or Air as the Terminal Oxidant (2000)

The osmium-catalyzed dihydroxylation of various olefins using molecular oxygen or air as the stoichiometric oxidant is reported. Aromatic olefins yield the corresponding diols in good to excellent chemoselectivities under optimized pH conditions (pH = 10.4−12.0). Air can be used under moderate pressures (3−9 bar) instead of dioxygen as the reoxidant. By increasing the oxygen content of the solution, it is possible to achieve highly efficient conversion at low catalyst amount (catalyst/substrate = 1:4000). Tri- and tetrasubstituted olefins are oxidized at pH > 11 to give the corresponding 1,2-diols in good to very good yields without requiring the addition of sulfonamides or other hydrolysis agents. Studies of the dihydroxylation of functionalized olefins demonstrate that the reaction conditions tolerate a variety of functional groups. In the presence of dihydroquinine or dihydroquinidine derivatives (Sharpless ligands), asymmetric dihydroxylations occur with lower enantioselectivities than tose of the classical K3[Fe(CN)6] reoxidation system.
CarbAcineto NP Test for Rapid Detection of Carbapenemase-Producing Acinetobacter spp (2014)

Multidrug-resistant Acinetobacter baumannii isolates, particularly those that produce carbapenemases, are increasingly reported worldwide. The biochemically based Carba NP test, extensively validated for the detection of carbapenemase producers among Enterobacteriaceae and Pseudomonas spp., has been modified to detect carbapenemase production in Acinetobacter spp. A collection of 151 carbapenemase-producing and 69 non-carbapenemase-producing Acinetobacter spp. were tested using the Carba NP test and a modified Carba NP protocol (the CarbAcineto NP test) in this study. The CarbAcineto NP test requires modified lysis conditions and an increased bacterial inoculum compared to those of the original Carba NP test. The Carba NP test detects metallo-β-lactamase producers but failed to detect the production of other carbapenemase types among Acinetobacter spp. In contrast, the newly designed CarbAcineto NP test, which is rapid and reproducible, detects all types of carbapenemases with a sensitivity of 94.7% and a specificity of 100%. This cost-effective technique offers a reliable and affordable technique for identifying carbapenemase production in Acinetobacter spp., which is a marker of multidrug resistance in those species. Its use will facilitate the recognition of these carbapenemases and prevent their spread.
Bottlenecks for metabolic engineering of isoflavone glycoconjugates in<i>Arabidopsis</i> (2002)

In view of their perceived chemopreventive activities against hormone-dependent cancers, cardiovascular disease, and postmenopausal ailments, there is considerable interest in engineering plants to contain isoflavone phytoestrogens. However, attempts to date have only resulted in low levels of isoflavone accumulation in non-legumes. Introducing soybean isoflavone synthase (IFS) into Arabidopsis thaliana leads to accumulation of low levels of genistein glycosides. Leaves of wild-type A. thaliana contain high levels of similar conjugates of the flavonols quercetin and kaempferol, which could be increased by threefold on introduction of an alfalfa chalcone isomerase transgene. Levels of genistein were not increased by expressing both IFS and alfalfa chalcone isomerase, but levels of flavonol conjugates were reduced to a greater extent than could be accounted for by flux into isoflavone. Introduction of IFS into the tt6 / tt3 double mutant blocked in flavonol, and anthocyanin synthesis resulted in high levels of genistein. The bottleneck for constitutive isoflavone production in Arabidopsis is, therefore, competition for flavanone between IFS and endogenous flavonol synthesis, and the flavonol pathway is reciprocally but disproportionately affected by IFS.
Microcavity plasma devices and arrays: a new realm of plasma physics and photonic applications (2005)

The confinement of low temperature, non-equilibrium plasmas to cavities having characteristic spatial dimensions <1 mm is providing new avenues of inquiry for plasma science. Not only is a previously unexplored region of parameter space now accessible, but the interaction of the plasma with its material boundaries raises fascinating questions and opportunities. Other scientific issues that come to the fore include scaling relationships and the collisional processes that become prevalent in a high pressure environment. The general characteristics of microplasmas, as well as several emerging applications, are briefly described here. With regard to the latter, emphasis will be placed on photonics and, specifically, the demonstration of large (500 × 500) arrays of microcavity plasma devices in Si, the observation of photodetection in the visible, near-infrared and ultraviolet by a microplasma, and the measurement of optical gain in the blue (λ ~ 460 nm) from a linear array of microplasmas in a ceramic structure.
Objective measures for speech quality assessment in wireless communications (2002)

Automatic assessment of speech quality is one of the most important problems in mobile communication. The primary goal of this article is to find an objective measure that accurately predicts user acceptance of speech signals recorded under varying noise conditions and channel impairments as well as signals subjected to various noise suppression/signal enhancement techniques. We report some preliminary results on correlation studies between several output-based/input-output-based objective measures and subjective scores. We propose to use these results to design a non-linear model for predicting the subjective quality using several simple objective measures.
A small, portable gas chromatograph-quadrupole mass spectrometer for on-site analysis (1994)

Gas chromatography-mass spectrometry (GC-MS) is the analytical tool of choice for the exact identification of unknown organic chemicals in environmental samples. Capillary gas chromatography, combined with the specific identification capabilities of mass spectrometry, allows the rapid and complete characterization of individual compounds in complex mixtures. As the technology has developed, many manufacturers have offered bench-top MS systems that provide a variety of analytical capabilities. Many instruments have been promoted as ``detectors for gas chromatography.`` More recently, manufacturers have offered integrated packages that can be transported to the field to provide analytical capabilities previously available only in the laboratory. The demonstrated field utility of these field-transportable units has triggered an interest in smaller, lighter weight, and more portable instruments. However, the current weight (>100 lb), large size, and laboratory-based power consumption requirements of these units is viewed as a liability by some potential field instrument users. Over the past several years, the interest in field-deployable instruments has resulted in research and development into smaller GC-MS systems designed with limited applications. While the development of these instruments is certainly worthwhile, a reliable and robust GC-MS instrument that clearly addresses the field-deployable needs for all environmental sampling and analysis would have considerable utility. We have developed portable instruments with analytical performance characteristics similar to those obtained with bench-top instruments. The current instrument, developed at LLNL and described here, was originally designed for use by on-site inspection teams supporting the Chemical Weapons Convention (CWC). The portability and expanded capabilities of this integrated instrument now make it a useful tool for environmental monitoring and on-site analysis studies.
The Enterococcus faecalis MSCRAMM ACE Binds Its Ligand by the Collagen Hug Model (2007)

We have determined the crystal structure of the ligand binding segment of the Enterococcus faecalis collagen binding MSCRAMM ACE (microbial surface components recognizing adhesive matrix molecules adhesin of collagen from enterococci). This segment is composed of two subdomains, N(1) and N(2), each adopting an IgG-like fold and forming a putative collagen binding surface at the interface between the two subdomains. This structure is very similar to that recently reported for CNA, the collagen binding MSCRAMM of Staphylococcus aureus, for which a unique ligand binding mechanism called the Collagen Hug was proposed. We suggest that ACE binds collagen by a similar mechanism and present the first biochemical evidence for this binding model. Replacing residues in the putative collagen binding trench of ACE N(2) with Ala residues affected collagen binding. A closed conformation of ACE stabilized by an engineered disulfide bond is unable to bind collagen. Finally, the importance of the residues in the N(2) extension in stabilizing the MSCRAMM-ligand complex is demonstrated by selected point and truncation mutations.
<title>Multifractal analysis of radiographic bone structure in osteoporosis</title> (1993)

We are developing noninvasive methods to evaluate bone structure in osteoporosis as demonstrated on conventional radiographs of the spine. One of these methods involves the estimation of fractal dimension of vertebral bodies in the spine of osteoporotic patients with fracture(s) elsewhere in the spin compared to patients without spine fracture. Fractal dimension was estimated using a surface 'area' method based on pixel gray level 'heights'. Analysis of the data by this method suggested a multifractal model of bone structure yielding two fractal dimensions for each case. The ability of these fractal dimensions to distinguish between cases with fracture elsewhere in the spine from those with no spine fracture was evaluated using receiver operating characteristic (ROC) curve analysis. An Az value of 0.87 using one of these fractal dimensions was significantly better than the Az of 0.60 using bone mass measurements for the same patients. The results suggest a possible value of a method using fractal dimension method for the improved prediction of fracture risk in osteoporosis patients.
Area-Selective Atomic Layer Deposition Patterned by Electrohydrodynamic Jet Printing for Additive Manufacturing of Functional Materials and Devices (2020)

There is an increasing interest in additive nanomanufacturing processes, which enable customizable patterning of functional materials and devices on a wide range of substrates. However, there are relatively few techniques with the ability to directly 3D print patterns of functional materials with sub-micron resolution. In this study, we demonstrate the use of additive electrohydrodynamic jet (e-jet) printing with an average line width of 312 nm, which acts as an inhibitor for area-selective atomic layer deposition (AS-ALD) of a range of metal oxides. We also demonstrate subtractive e-jet printing with solvent inks that dissolve polymer inhibitor layers in specific regions, which enables localized AS-ALD within those regions. The chemical selectivity and morphology of e-jet patterned polymers towards binary and ternary oxides of ZnO, Al<sub>2</sub>O<sub>3</sub>, and SnO<sub>2</sub> were quantified using X-ray photoelectron spectroscopy, atomic force microscopy, and Auger electron spectroscopy. This approach enables patterning of functional oxide semiconductors, insulators, and transparent conducting oxides with tunable composition, Å-scale control of thickness, and sub-μm resolution in the <i>x-y</i> plane. Using a combination of additive and subtractive e-jet printing with AS-ALD, a thin-film transistor was fabricated using zinc-tin-oxide for the semiconductor channel and aluminum-doped zinc oxide as the source and drain electrical contacts. In the future, this technique can be used to print integrated electronics with sub-micron resolution on a variety of substrates.
Low Core Loss Characteristics of MnMgZn Ferrite with Substituted CuO. (1997)

The effects of substitutive CuO for MgO on the core loss characteristics of MnMgZn ferrite were studied with reference to the initial permeability, microstructure, and conductivity. Superior core loss was achieved by CuO 2-5 mol % subsititution in MnMgZn ferrite. Subsititution of CuO is effective in reducing both hysteresis and eddy current losses. This improvement can be correlated with uniformly sized grains and high resistivity. High resistivity attained by CuO substitution in MnMgZn ferrite reduced core loss at high frequencies.
The Role of the Substrate Surface Morphology and Water in Growth of Vertically Aligned Single-Walled Carbon Nanotubes (2008)

Growth of high quality, vertically aligned single-walled carbon nanotubes (carpets) is achieved using a rapid insertion hot filament chemical vapor deposition (HF-CVD) technique. The effect of the substrate morphology on growth is explored by comparing carpets grown on epitaxially polished MgO substrates to those grown on "as-cut", macroscopically rough MgO substrates. Depending on the substrate morphology, we observe differences in both the overall carpet morphology as well as the diameter distribution of nanotubes grown in the carpet based on optical measurements. In addition, we explore the role of water in the growth of carpets on MgO and the conventional Al2O3 coated Si substrates. We find that the addition of a small amount of water is beneficial to the growth rates of the SWNT carpets, enhancing the growth rates by up to eight times.