gebhart/patrepeval huggingface dataset:
Catabolite Repression of Tryptophanase in <i>Escherichia coli</i> (1971)

Catabolite repression of tryptophanase was studied in detail under various conditions in several strains of Escherichia coli and was compared with catabolite repression of beta-glactosidase. Induction of tryptophanase and beta-galactosidase in cultures grown with various carbon sources including succinate, glycerol, pyruvate, glucose, gluconate, and arabinose is affected differently by the various carbon sources. The extent of induction does not seem to be related to the growth rate of the culture permitted by the carbon source during the course of the experiment. In cultures grown with glycerol as carbon source, preinduced for beta-galactosidase or tryptophanase and made permeable by ethylenediaminetetraacetic acid (EDTA) treatment, catabolite repression of tryptophanase was not affected markedly by the addition of cAMP (3',5'-cyclic adenosine monophosphate). Catabolite repression by glucose was only partially relieved by the addition of cAMP. In contrast, under the same conditions, cAMP completely relieved catabolite repression of beta-galactosidase by either pyruvate or glucose. Under conditions of limited oxygen, induction of tryptophanase is sensitive to catabolite repression; under the same conditions, beta-galactosidase induction is not sensitive to catabolite repression. Induction of tryptophanase in cells grown with succinate as carbon source is sensitive to catabolite repression by glycerol and pyruvate as well as by glucose. Studies with a glycerol kinaseless mutant indicate that glycerol must be metabolized before it can cause catabolite repression. The EDTA treatment used to make the cells permeable to cAMP was found to affect subsequent growth and induction of either beta-galactosidase or tryptophanase much more adversely in E. coli strain BB than in E. coli strain K-12. Inducation of tryptophanase was reduced by the EDTA treatment significantly more than induction of beta-galactosidase in both strains. Addition of 2.5 x 10(-3)m cAMP appeared partially to reverse the inhibitory effect of the EDTA treatment on enzyme induction but did not restore normal growth.
<i>Kras</i>, <i>Egfr</i>, and <i>Tp53</i> Mutations in B6C3F1/N Mouse and F344/NTac Rat Alveolar/Bronchiolar Carcinomas Resulting from Chronic Inhalation Exposure to Cobalt Metal (2015)

Rodent lung tumors are morphologically similar to a subtype of human lung adenocarcinomas. The objective of this study was to evaluate Kirsten rat sarcoma oncogene homolog (Kras), epidermal growth factor receptor (Egfr), and tumor protein 53 (Tp53) mutations, which are relevant to human lung cancer, in cobalt metal dust (CMD)-induced alveolar/bronchiolar tumors of B6C3F1/N mice and F344/NTac rats. Kras mutations were detected in 67% (mice) and 31% (rats) of CMD-induced lung tumors and were predominantly exon 1 codon 12 G to T transversions (80% in mice and 57% in rats). Egfr mutations were detected in 17% (both mice and rats) of CMD-induced lung tumors and were predominantly in exon 20 with 50% G to A transitions (mice and rats). Tp53 mutations were detected in 19% (mice) and 23% (rats) of CMD-induced lung tumors and were predominant in exon 5 (mice, 69% transversions) and exon 6 (rats, all transitions). No mutations were observed for these genes in spontaneous lung tumors or normal lungs from untreated controls. Ames assay indicated that CMD is mutagenic in the absence but not in the presence of S9 mix. Thus, the mutation data (G to T transversions) and Ames assay results suggest that oxidative damage to DNA may be a contributing factor in CMD-induced pulmonary carcinogenesis in rodents.
Assembling Alternate Dye−Polyion Molecular Films by Electrostatic Layer-by-Layer Adsorption (1997)

Electrostatic alternate adsorption was successfully employed for low-molecular-weight dyes, leading to a large variety of dye−polyion layer-by-layer assemblies. The assembling process of individual dye−polyion layers of Congo Red (CR)−poly(diallyldimethylammonium chloride) (PDDA) was investigated by using a quartz crystal microbalance (QCM). The in-situ QCM measurement revealed that the dye adsorption occurred at a rate similar to that of conventional polyion adsorption. Successful assembly of the CR layer was confirmed also by increasing intensities in the UV adsorption. The molecular aggregation within the dye layer was inferred from the observed absorption shift in the case of CR−PDDA. Apparently, stable film formation is promoted by dye aggregation in the adsorbed layer, although the extent of film growth was independent of conceivable aggregation in the solution. Successive frequency decreases due to film growth were observed for other representative dyes under optimized conditions. Comparison of the film thickness estimated from QCM frequency shift with the molecular dimension of individual dyes suggests the formation of well-packed monomolecular dye layers that is affected by size, number of charge, and spatial orientation of dye molecules. The alternate layer-by-layer assembly is now extended from linear polyions to other macroions (proteins and inorganic plates) and charged small molecules. Advantages and disadvantages of the alternate assembly were discussed relative to those of the Langmuir−Blodgett technique.
STUDIES ON THE MACROLIDE ANTIBIOTIC YL-704 COMPLEX. III (1974)

New macrolide antibiotics YL-704 A1 and B1 were isolated from the culture broth of Streptomyces platensis subsp. malvinus MCRL 0388 and the structures of them were elucidated with physicochemical microanalyses including the mass spectrometry of their derivatives and the chemical degradation studies. The structure of the sixteen-membered aglycone was the same in YL-704 A1 and B1, while, the acyl groups of the sugar were isovaleryl and propionyl, respectively. Finally, dipropionyl YL-704 A1 was entirely identified with tripropionyl leucomycin A1.
Ship Shoal Block 91 Field, offshore Louisiana; discovery and development of a stratigraphic field (1987)

Abstract The Ship Shoal 91 field is a subtle stratigraphic play which consists of a seismic amplitude whose updip limits do not fit structure. The amplitude corresponds to both gas and oil in the Upper Miocene sand. To attempt to predict pay sand distribution accurately, several geologic models were defined as development drilling progressed. The models utilized self-potential curve shape, core, and seismic character analyses, combined with computer modeling studies, engineering data, and scanning electron microscope studies. Four geologic models evolved, ranging from a structural trap formed by small faults, to a stratigraphic pinchout of the pay sand, to a channel sand, and finally to a complex channel sand, resulting in the current model: a faulted stratigraphic trap.The development strategy for determining well locations also evolved, due to unexpected well results. The initial strategy was based on the presence of seismic amplitudes, until it became apparent that the amplitude alone is not a reliable hydrocarbon indicator. The revised strategy is based on complex attribute analysis, including the amplitude envelope and the weighted frequency.The discovery and development of this stratigraphic field required thorough integration of geology, geophysics, and engineering disciplines. The Ship Shoal 91 field demonstrates that complex stratigraphic fields are still of exploration interest and can be successfully developed by using an integrated approach.
High performance 1.3 μm vertical-cavity surface-emitting lasers with oxygen-implanted confinement regions and wafer-bonded mirrors (2002)

We show schematically the oxygen-implanted VCSELs. The devices consist of an oxygen implanted p-GaAs-AlGaAs (28 pairs) mirror, AlGaInAs-InP strain-compensated multiple quantum well (SC-MQW) cavity layers, and a top ZnSe/MgF (6 pairs) dielectric mirror.
Transformation optics and cloaking (2013)

Invisibility, a long sought-for speculation in science fiction, has been turned into reality in the laboratory through the use of a theoretical technique called Transformation Optics. The principles of transformation optics show that any desired smooth deformation of the electromagnetic field can be implemented exactly by an appropriately engineered metamaterial. All demonstrations of cloaking to date have had limitations, however, reflecting our technological inability to implement the transformation optics algorithm exactly. However, the scientific principles leading to perfect invisibility are now established, and practical improvements on the initial designs are now occurring very rapidly. Most recently, researchers have re-examined transformation optics to include time as well as space, describing and then implementing the concept of a cloak that hides events, a conceptual breakout that promises many new applications. This review describes the general ideas underlying transformation optics, and how the various types of cloak based on these ideas have been implemented practically to date.
Supercritical flow near an abrupt wall deflection (1994)

The supercritical flow near an abrupt wall deflection is investigated experimentally and by computer simulations. An extensive series of tests were conducted on a 500 mm wide flume with Froude number up to 8 and wall deflection angle up to 11.3°. A special inlet box was installed to provide smooth flow conditions at the flume entrance. By analyzing the experimental data, explicit expressions are derived for the height of the shock and the velocity ratio. Experimental results are presented in the form of universal plots of the shock surface and the two-dimensional velocity field. These may be utilized for engineering applications or for the verification of mathematical models. The flow field near a wall deflection was computed by using a two-dimensional flow model based on the numerical solution of steady, shallow-water equations by the MacCormack explicit finite-difference scheme. The computed and measured flow depths and flow velocities are compared and are found to be in satisfactory agreement where the assumption of hydrostatic pressure distribution is valid. Although the computer simulation can predict the location of the jump as well as its equilibrium depth, several features of the flow resulting from non-hydrostatic pressure distribution are not resolved properly.
Antiepileptic Drug Mechanisms of Action (1993)

Clinically used antiepileptic drugs (AEDs) decrease membrane excitability by interacting with ion channels or neurotransmitter receptors. Currently available AEDs appear to act on sodium channels, GABAA receptors, or calcium channels. Phenytoin, carbamazepine, and possibly valproate (VPA) decrease high-frequency repetitive firing of action potentials by enhancing sodium channel inactivation. Benzodiazepines and barbiturates enhance GABAA receptor-mediated inhibition. Ethosuximide and possibly VPA reduce a low-threshold calcium current. The mechanisms of action of AEDs currently under development are less clear. Lamotrigine may decrease sustained high-frequency repetitive firing. The mechanisms of action of felbamate are unknown. Gabapentin (GBP) appears to bind to a specific binding site in the central nervous system with a restricted regional distribution, but the identity of the binding site and the mechanism of action of GBP remain uncertain.
The Concentration of Synaptically Released Glutamate Outside of the Climbing Fiber–Purkinje Cell Synaptic Cleft (1999)

AMPA receptors and glutamate transporters expressed by cerebellar Bergmann glial cells are activated by neurotransmitter released from climbing fibers (). Based on anatomical evidence, this is most likely the result of glutamate diffusing out of the climbing fiber-Purkinje cell synaptic clefts (). We used the change in the EC50 of the Bergmann glia AMPA receptors produced by cyclothiazide (CTZ) to estimate the concentration of glutamate reached at the glial membrane. The decrease of the EC50 gives rise to a concentration-dependent potentiation of the AMPA receptor-mediated responses (). By comparing the increase in amplitude of the AMPA receptor response in the Bergmann glia (840 +/- 240%; n = 8) with the shift in the glutamate dose-response curve measured in excised patches (EC50, 1810 microM in control vs 304 microM in CTZ), we estimate that the extrasynaptic transmitter concentration reaches 160-190 microM. This contrasts with the concentration in the synaptic cleft, thought to rapidly rise above 1 mM, but is still high enough to activate glutamate receptors. These results indicate that the sphere of influence of synaptically released glutamate can extend beyond the synaptic cleft.
A high performance architecture for real-time signal processing and matrix operations (2003)

The authors present the block data flow architecture (BDFA) which is an alternative to the systolic array and the wavefront array for locally recursive algorithms such as those used for digital signal processing, image processing, and matrix operations. The BDFA retains the advantageous features of a systolic array or a waveform array, such as regularity, modularity, and local interconnection. However, it uses a data partitioning strategy in addition to an algorithm partitioning strategy to reduce the data dependency, to decrease the interprocessor communication requirements and to decrease the hardware complexity compared to systolic and wavefront arrays. The BDFA also uses block data processing and the block data flow paradigm to minimize system management overhead due to communication protocols. Thus, the processors in a BDFA operate efficiently to achieve a system with a high throughput and a high efficiency.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Superconducting Suspension for a Sensitive Accelerometer (1965)

Permanent magnet suspension over superconducting surface used as linear bearing for low level accelerometer
Subject-Specific p-FE Analysis of the Proximal Femur Utilizing Micromechanics-Based Material Properties (2008)

Novel subject-specific high-order finite element models of the human femur based on computer tomographic (CT) data are discussed with material properties determined by two different methods, empirically based and micromechanics based, both being determined from CT scans. The finite element (FE) results are validated through strain measurements on a femur harvested from a 54-year-old female. To the best of our knowledge, this work is the first to consider an inhomogeneous Poisson ratio and the first to compare results obtained by micromechanics-based material properties to experimental observations on a whole organ. We demonstrate that the FE models with the micromechanics-based material properties yield results which closely match the experimental observations and are in accordance with the empirically based FE models. Because the p-FE micromechanics-based results match independent experimental observations and may provide access to patient-specific distribution of the full elasticity tensor components, it is recommended to use a micromechanics-based method for subject-specific structural mechanics analyses of a human femur.
Performance of a novel selection diversity technique in an experimental TDMA system for digital portable radio communications (2003)

The authors present the measured average bit error and block error ratio performance of a coherent burst time-division multiple-access radio link in a simulated flat Rayleigh fading environment using a unique technique for implementing two-branch selection diversity. The link consists of a 500-kb/s quadrature amplitude modulation burst transmitter and a coherent receiver with a fast carrier recovery circuit. The receiver is switched between two signals which are corrupted by uncorrelated Rayleigh fading. If the transmitter is on before the actual data burst, received signal measurement and selection can be performed just before the reception of a data burst. This way, when data is to be demodulated, the receiver is already switched to the branch with the higher power. With this technique, the performance of selection diversity is achieved with only one receiver chain. Experimental results are presented showing link performance as functions of Rayleigh fading rate and the time delay between signal measurement/diversity selection and the actual data burst.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
An analysis of noise propagation in computed <i>T</i><sub>2</sub>, pseudodensity, and synthetic spin‐echo images (1986)

Methods are reviewed for estimating the transverse relaxation time T2 and the pseudodensity (PD) from spin-echo measurements acquired at an arbitrary set of echo times [TEi]. Least-squares fitting is applied to the logarithmically processed signals for the case in which the weights are proportional to the inverse of the logarithmically transformed signal variances (the minimum variance case). General formulas are derived for the estimated noise levels in the PD and T2 estimates due to the propagation of uncertainties in the original measurements. It is shown that the T2 and PD estimates are anticorrelated. Additionally, an expression is derived for the variance in a synthetic spin-echo signal subsequently formed from the PD and T2 estimates. It is shown that under many circumstances a signal synthesized at some echo time can have a signal-to-noise ratio superior to that in a signal directly acquired at that time. Experimental measurements made on phantoms match the theoretical predictions to a high degree.
A trajectory-based computational model for optical flow estimation (1995)

A new computational model for optical flow estimation is proposed. The proposed model utilizes trajectory information present in a multiframe spatio-temporal volume. Optical flow estimation is formulated as an optimization problem. The solution to this optimization problem yields a velocity field corresponding to smoothest and shortest trajectories of constant intensity points within the spatio-temporal volume. The approach is motivated by principles of inertia of motion and least action in physics and vision psychology. An analogy between a trajectory and a "thin wire" is discussed. A simple mechanism for handling trajectory discontinuities is also incorporated. The optimization problem is solved by stochastic relaxation techniques. Some experimental results and performance comparisons with two existing optical flow estimation techniques are presented to demonstrate the effectiveness of the proposed approach.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Synthesis, Characterization, and Activity Studies of Vanadia Supported on Zirconia and Phosphorus-Modified Zirconia (1999)

A series of catalysts with vanadia contents varying between 1 and 14 wt % were prepared by the wet impregnation technique on zirconia and phosphorus-modified zirconia. The catalysts were characterized by employing X-ray diffraction (XRD), electron spin resonance (ESR) spectroscopy, 51V, 31P, and 1H solid-state magic angle spinning nuclear magnetic resonance (MAS NMR), Fourier transform Raman spectroscopy (FT-Raman), diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), and Brunauer−Emmett−Teller (BET) surface area measurements. The activities of the catalysts were determined by an ethanol partial oxidation reaction. 51V solid-state NMR studies of both series of catalysts indicated the presence of tetrahedral vanadate species at lower loadings, and octahedrally coordinated vanadium species at higher concentrations. DRIFTS studies of the catalysts were in conformity with NMR studies as the vibrations corresponding to tetrahedral vanadate species were observed at low V2O5 loadings and at higher vanadia contents the vibrations corresponding to polymeric decavanadate species were seen. All of the XRD, ESR, 51V solid-state NMR, FT-Raman, and DRIFTS results indicated weaker interaction of vanadia with zirconia support upon phosphate modification. Activity studies were in agreement with spectroscopic data, as reflected in higher ethanol partial oxidation activities of the V2O5/ZrO2 catalysts.
Accurate density measurements of reference liquids by a magnetic suspension balance (2004)

A density measurement system with a magnetic suspension balance has been developed for accurate density measurements of reference liquids. In this system, the buoyancy force of a sample liquid acting on a sinker of silicon crystal is measured through a magnetic suspension coupling. For the accurate density measurements, the volume of the silicon sinker has been calibrated with a relative combined standard uncertainty of 1.4 × 10−6 by the pressure-of-floatation method in a manner that is traceable to the International System of Units. The temperature of the sample liquid is controlled within a fluctuation of less than 1 mK. The effect of the magnetic property of the sample liquid on the density measurement has been examined. Theoretical calculation of the magnetic interaction in the densimeter has clarified that the diamagnetic property of n-tridecane, if not corrected, will result in a relative systematic error of 60 × 10−6 in the density measurement. The densities of some candidates for the reference liquids, iso-octane, n-nonane, n-tridecane, water, 2,4-dichlorotoluene, 3,4-dichlorotoluene and bromobenzene have been measured. The relative combined standard uncertainty in the density measurement of bromobenzene has been estimated to be 6.7 × 10−6 at 20 °C under atmospheric pressure.
Autophagy, amyloidogenesis and Alzheimer disease (2007)

Autophagy is the sole pathway for organelle turnover in cells and is a vital pathway for degrading normal and aggregated proteins, particularly under stress or injury conditions. Recent evidence has shown that the amyloid beta peptide is generated from amyloid beta precursor protein (APP) during autophagic turnover of APP-rich organelles supplied by both autophagy and endocytosis. Abeta generated during normal autophagy is subsequently degraded by lysosomes. Within neurons, autophagosomes and endosomes actively form in synapses and along neuritic processes but efficient clearance of these compartments requires their retrograde transport towards the neuronal cell body, where lysosomes are most concentrated. In Alzheimer disease, the maturation of autophagolysosomes and their retrograde transport are impeded, which leads to a massive accumulation of ;autophagy intermediates' (autophagic vacuoles) within large swellings along dystrophic and degenerating neurites. The combination of increased autophagy induction and defective clearance of Abeta-generating autophagic vacuoles creates conditions favorable for Abeta accumulation in Alzheimer disease.
Experience with distant pathology demonstrations for clinicians in hospitals without local pathologists through the Swedish telepathology work station. (1995)

Conferences between pathologists and clinicians are routinely important at each hospital which has its own department of pathology. With the aid of telepathology, such conferences can be facilitated to provide results similar to those in hospitals with their own pathological service. Our Department serves the hospital in Motala, which is located 50 km west of Linköping. We now have telepathology conferences every second week with the surgeons and every second week with colleagues in internal medicine. The equipment we use is LabEye, which is produced by Innovativ Vision AB in Linköping. This equipment includes mouse pointers at both stations which are always visible in the images at both ends of the system. The quality of images received in Motala is very good, allowing discussion of details regarding the specimens, especially the cytological ones. Our experiences with these conferences have been very good.