gebhart/patrepeval huggingface dataset:
Decatenating activity of Escherichia coli DNA gyrase and topoisomerases I and III during oriC and pBR322 DNA replication in vitro. (1994)

oriC and pBR322 DNA replication, reconstituted with purified replication proteins, has been used to study the functional activities of Escherichia coli topoisomerase I, DNA gyrase, and topoisomerase III during the final stages of DNA replication. In the oriC system, DNA gyrase-catalyzed decatenation of daughter DNA molecules was very inefficient, whereas topoisomerase III could catalyze complete decatenation. In the pBR322 DNA replication system, almost all the daughter DNA molecules could be decatenated by DNA gyrase alone in the absence of salt. Decatenation by DNA gyrase in the pBR322 system was completely inhibited, without a concomitant inhibition of DNA synthesis, by the addition of physiological concentrations of salt. Topoisomerase III, however, could decatenate all of the daughter DNA molecules in the pBR322 system, even in the presence of high concentrations of salt. A similar effect could not be observed in the oriC system, because the addition of salt inhibited DNA synthesis. Topoisomerase I was incapable of catalyzing decatenation under any conditions examined in either the oriC or pBR322 replication system. The addition of topoisomerase I to the replication systems resulted only in an inhibition of DNA synthesis.
On the cost of caching locator/ID mappings (2007)

Very recent activities in the IETF and in the Routing Research Group (RRG) of the IRTG focus on defining a new Internet architecture, in order to solve scalability issues related to interdo-main routing. The approach that is being explored is based on the separation of the end-systems' addressing space (the identifiers) and the routing locators' space. This separation is meant to alleviate the routing burden of the Default Free Zone, but it implies the need of distributing and storing mappings between identifiers and locators on caches placed on routers. In this paper we evaluate the cost of maintaining these caches when the distribution mechanism is based on a pull model. Taking as a reference the LISP protocol, we base our evaluation on real Netflow traces collected on the border router of our campus network. We thoroughly analyze the impact of the locator/ID separation, and related cost, showing that there is a trade-off between the dynamism of the mapping distribution protocol, the demand in terms of bandwidth, and the size of the caches.
Definition of a specific interaction between the early T lymphocyte activation 1 (Eta-1) protein and murine macrophages in vitro and its effect upon macrophages in vivo. (1990)

The Eta-1 gene specifies a secreted product of activated T cells and is associated with genetic resistance to infection by an obligate intracellular bacterium. Previous studies have suggested that eta-1 might affect the ability of macrophages to migrate to the site of bacterial infection and/or to inhibit intracellular bacterial growth. We therefore examined the interaction of eta-1 with macrophages in vitro and in vivo. We find that macrophages express approximately 10(4) eta-1 receptors/cell and each receptor has a Kd of approximately 5 x 10(-10) M. The subsequence of eta-1 containing an RGD motif is required for binding because a synthetic peptide containing the eta-1 RGD domain inhibited protein attachment to macrophages. We also found that subcutaneous inoculation of mice with eta-1 resulted in a cellular infiltrate comprised primarily of macrophages. We propose that the interaction between eta-1 and its receptor on macrophages results in a change in macrophage physiology resulting in accumulation of these cells at extravascular sites.
Compensation for the effect of cylinder friction in the pressure feedback control of the nip load on a paper center winder (2002)

This paper describes the development of a control method for paper center winder. The control method includes pressure feedback control of the nip load between the paper roll and the backing roll based on an electrohydraulic servo system. In pressure feedback control of the nip load, the set points for pressure are calculated using a continuous function which is fitted between the target points calculated in the definition of the winding cycle. The cylinder friction is compensated for by a function which takes into account the effects of viscous friction, static friction, Coulomb's friction and cylinder load pressure on the frictional force. The functioning of the control method has been verified experimentally using equipment containing the functions of a paper center winder.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Click-Like Reactions with the Inert HCB<sub>11</sub>Cl<sub>11</sub><sup>–</sup>Anion Lead to Carborane-Fused Heterocycles with Unusual Aromatic Character (2013)

The chlorinated carba-closo-dodecaborate anion HCB11Cl11(-) is an exceptionally stable molecule and has previously been reported to be substitutionally inert at the B-Cl vertices. We present here the discovery of base induced cycloaddition reactions between this carborane anion and organic azides that leads to selective C and B functionalization of the cluster. A single crystal X-ray diffraction study reveals bond lengths in the heterocyclic portion of the ring that are shortened, which suggests electronic delocalization. Molecular orbital analysis of the ensuing heterocycles reveals that two of the bonding orbitals of these systems resemble two of the doubly occupied π-MOs of a simple 5-membered Hückel-aromatic, even though they are entangled in the carborane skeleton. Nucleus independent chemical shift analysis indicates that both the carborane cluster portion of the molecule and the carborane fused heterocyclic region display aromatic character. Computational methods indicate that the reaction likely follows a stepwise addition cyclization pathway.
Inactivation of<i>sll1556</i>in<i>Synechocystis</i>Strain PCC 6803 Impairs Isoprenoid Biosynthesis from Pentose Phosphate Cycle Substrates In Vitro (2004)

In cyanobacteria many compounds, including chlorophylls, carotenoids, and hopanoids, are synthesized from the isoprenoid precursors isopentenyl diphosphate (IPP) and dimethylallyl diphosphate. Isoprenoid biosynthesis in extracts of the cyanobacterium Synechocystis strain PCC 6803 grown under photosynthetic conditions, stimulated by pentose phosphate cycle substrates, does not appear to require methylerythritol phosphate pathway intermediates. The sll1556 gene, distantly related to type 2 IPP isomerase genes, was disrupted by insertion of a Kanr cassette. The mutant was fully viable under photosynthetic conditions although impaired in the utilization of pentose phosphate cycle substrates. Compared to the parental strain the Deltasll1556 mutant (i) is deficient in isoprenoid biosynthesis in vitro with substrates including glyceraldehyde-3-phosphate, fructose-6-phosphate, and glucose-6-phosphate; (ii) has smaller cells (diameter ca. 13% less); (iii) has fewer thylakoids (ca. 30% less); and (iv) has a more extensive fibrous outer wall layer. Isoprenoid biosynthesis is restored with pentose phosphate cycle substrates plus the recombinant Sll1556 protein in the Deltasll1556 supernatant fraction. IPP isomerase activity could not be demonstrated for the purified Sll1556 protein under our in vitro conditions. The reduction of thylakoid area and the effect on outer wall layer components are consistent with an impairment of isoprenoid biosynthesis in the mutant, possibly via hopanoid biosynthesis. Our findings are consistent with an alternate metabolic shunt for biosynthesis of isoprenoids.
Synthesis and Antibacterial Activity of New Diaryldiamines (2012)

Several new quinolines and quinazolines ( 4, 10, 13 ) have been synthesized from cheap and readily available chemicals through a series of simple chemical transformations. Most of the synthesized compounds have been evaluated for antibacterial activity against Gram positive and Gram negative strains. Some of the synthesized compounds displayed interesting activity but not very promising for further development.
Doppler radar characteristics of precipitation at vertical incidence (1973)

A comprehensive review and extension of the theoretical bases for the measurement of the characteristics of rain and snow with vertically pointing Doppler radar are presented. The drop size distribution in rain can be computed from the Doppler spectrum, provided that the updraft can be estimated, but difficulties are involved in the case of snow. Doppler spectra and their moments are computed for rain by using various power law relations of fall speed υ versus particle diameter D and an exponential fit to the actual fall speed data. In the former case, there is no sharp upper bound to the spectra and all the spectral moments increase with rainfall rate R without limit; in the latter case, there is a sharp upper bound of the spectra corresponding to the limiting terminal velocity of raindrops, and the spectral moments approach an asymptote. Accordingly, the power laws are useful approximations over only limited ranges of precipitation rate. A comparison of theoretical and experimental mean Doppler velocity 〈υ〉 as a function of radar reflectivity factor Z shows that the empirical relation 〈υ〉 = 2.6 Z 0.107 of J. Joss and A. Waldvogel seems to be the only practical relation; even so, the scatter in 〈υ〉 is about ±1 m sec −1 . This is also the kind of error to be expected in measuring updraft speeds by present methods. Such updraft errors result in unacceptably large errors in the drop number concentration estimated from Doppler spectra. In the absence of updrafts the mean Doppler velocity 〈υ〉 is uniquely related to Λ, the slope of the exponential drop size distribution. Simultaneous measurements of Z and 〈υ〉 can then be used to estimate N 0 , Λ, D 0 , M , and R , where N 0 is the intercept of the exponential drop size distribution at D = 0, D 0 is the median volume diameter, and M is the liquid‐water content.
Determining shear‐wave transverse isotropy from borehole stoneley waves (2001)

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2001Determining shear‐wave transverse isotropy from borehole stoneley wavesAuthors: X. M. TangX. M. TangBaker Atlas, Houstonhttps://doi.org/10.1190/1.1816612 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Permalink: https://doi.org/10.1190/1.1816612FiguresReferencesRelatedDetails SEG Technical Program Expanded Abstracts 2001ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2001 Pages: 2135 publication data© 2001 Copyright © 2001 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 03 Jan 2005 CITATION INFORMATION X. M. Tang, (2001), "Determining shear‐wave transverse isotropy from borehole stoneley waves," SEG Technical Program Expanded Abstracts : 341-344. https://doi.org/10.1190/1.1816612 Plain-Language Summary PDF DownloadLoading ...
IMPROVED COUPLING TO INFRARED WHISKER DIODES BY USE OF ANTENNA THEORY (1970)

It is shown that the dependence of the output of a whisker diode on its orientation in the polarized beam of an infrared laser can be explained on the basis of simple long-wire antenna theory. Outstanding improvements in coupling the diode to the radiation field can result when this fact is utilized in applications.
Block Spread OFDMA with STC MIMO for Improved Frequency and Spatial Diversity over Broadband Wireless Access Uplink (2010)

A novel combination of block spread orthogonal frequency division multiple access (BS-OFDMA) with space-time coded multiple input multiple output (STC MIMO) scheme is proposed for broadband wireless access uplink transmission. Using complex exponential spreading sequences, the block spreading technique can efficiently generate precoded OFDMA signal to exploit frequency diversity. An Alamouti STC MIMO encoding technique is incorporated with the block spreading to achieve further spatial diversity. The performance of the proposed STC-BS-OFDMA system using minimum mean squared error equalization is analyzed, and a closed-form asymptotical bit error rate expression is derived. Simulation results are also given to demonstrate the improved diversity performance as compared with other OFDMA schemes. The proposed techniques are well suited for future broadband wireless access systems such as 3G LTE and 4G.
Triangular Units as a Bias Detergent for Students of Physics (1955)

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Hydrides formed from intermetallic compounds of two transition metals: a special class of ternary alloys (1982)

The authors review available experimental information on the existence, thermodynamic stability and physical properties of hydrides formed by the absorption of hydrogen gas in intermetallic compounds of two transition metals. The emphasis is on stability. It is shown that empirical models for the stability of ternary hydrides can be reconciled with ideas based on the results of band structure calculations of (binary) metallic hydrides. It is concluded that metallic hydrides can be looked upon as alloys of metallic hydrogen. In addition to the thermodynamic properties of ternary metallic hydrides the authors discuss experimental information on electronic properties (magnetic, super-conductivity, band structure features) and on crystallographic and metallurgical properties (neutron scattering, nuclear and electron spin resonance, Mossbauer spectroscopy, diffusion). Applications are briefly reviewed.
Diffraction grating scanners using polysilicon micromotors (1999)

This paper describes polysilicon micromotors with single and pyramidal diffraction grating elements fabricated on the polished surface of large-area rotors for optical scanning applications. While taking full advantage of planar processing, such scanners have high-quality scan profiles, good efficiency, meter working distances, and multiple out of plane beam diffraction orders. Chemical-mechanical polishing was used to reduce the 5-/spl mu/m-thick polysilicon rotors' average surface roughness from 420 /spl Aring/ to below 17 /spl Aring/, with less than 1500-/spl Aring/ film removal, improving the optical performance of the gratings as well as the definition, delineation, and side wall quality of the device features. Self-assembled monolayers (SAM) were found to improve the overall micromotor's dynamic performance. SAM-coated scanners could operate at voltages as low as 15 V and maximum operational speeds of 5200 rpm. The gratings were tested optically at 633-nm wavelength and were verified to have spatial periods of 1.80 and 3.86 /spl mu/m, closely matching their design values. Stepping and continuous mode dynamic operation of the scanners was demonstrated with visible diffraction orders at meter distances away.
GATA Transcription Factors Regulate the Expression of the Human Eosinophil-derived Neurotoxin (RNase 2) Gene (2009)

The transcription factors GATA-1 and GATA-2 have been implicated in promoting differentiation of eosinophilic leukocytes. In this study, we examined the roles of GATA-1 and GATA-2 in activating transcription of the secretory ribonuclease, the eosinophil-derived neurotoxin (EDN/RNase 2). Augmented expression of both GATA-1 and GATA-2 was detected in eosinophil promyelocyte HL-60 clone 15 cells in response to biochemical differentiation with butyric acid. Deletion or mutation of one or both of the two consensus GATA-binding sites in the extended 1000-bp 5' promoter of the EDN gene resulted in profound reduction in reporter gene activity. Antibody-augmented electrophoretic mobility shift and chromatin immunoprecipitation analyses indicate that GATA-1 and GATA-2 proteins bind to both functional GATA consensus sequences in the EDN promoter. Interestingly, RNA silencing of GATA-1 alone had no impact on EDN expression; silencing of GATA-2 resulted in diminished expression of EDN, and also diminished expression of GATA-1 in both butyric acid-induced HL-60 clone 15 cells and in differentiating human eosinophils derived from CD34(+) hematopoietic progenitors. Likewise, overexpression of GATA-2 in uninduced HL-60 clone 15 cells resulted in augmented transcription of both EDN and GATA-1. Taken together, our data suggest that GATA-2 functions directly via interactions with the EDN promoter and also indirectly, via its ability to regulate the expression of GATA-1 in differentiating eosinophils and eosinophil cell lines.
Radial partition immunoassay applied to automated quantification of human choriogonadotropin with use of two monoclonal antibodies. (1986)

We describe a novel application of radial partition immunoassay to quantification of human choriogonadotropin (hCG). In this "sandwich"-type assay, two monoclonal antibodies, specific for different sites on the intact molecule are used. The solid phase consists of tabs of glass-fiber filter paper containing a pre-immobilized antibody specific for the alpha subunit of hCG. The patient's sample is first applied directly to the central "reaction zone" of the tab, allowing hCG to bind to the solid-phase antibody. Then a buffered solution containing enzyme-labeled Fab' fragments of a monoclonal antibody specific for the beta subunit of hCG is applied, initiating "sandwich" formation. Finally, a wash buffer containing a fluorogenic substrate is applied, eluting unbound conjugate to the tab periphery. Bound enzyme conjugate is quantified by measuring the rate of increase in fluorescence. Rates are converted to clinical units by comparison with a stored calibration curve. Elapsed time from sample application to results is less than 8 min. Specific performance characteristics of this assay are reported.
Zafirlukast Metabolism by Cytochrome P450 3A4 Produces an Electrophilic α,β-Unsaturated Iminium Species That Results in the Selective Mechanism-Based Inactivation of the Enzyme (2005)

Zafirlukast is a leukotriene antagonist indicated for the treatment of mild to moderate asthma, but the drug has been associated with occasional idiosyncratic hepatotoxicity. Structurally, zafirlukast is similar to 3-methylindole because it contains an N-methylindole moiety that has a 3-alkyl substituent on the indole ring. The results presented here describe the metabolic activation of zafirlukast via a similar mechanism to that described for 3-methylindole. NADP(H)-dependent biotransformation of zafirlukast by hepatic microsomes from rats and humans afforded a reactive metabolite, which was detected as its GSH adduct. Mass spectrometry and NMR data indicated that the GSH adduct was formed by the addition of GSH to the methylene carbon between the indole- and methoxy-substituted phenyl rings of zafirlukast. The formation of this reactive metabolite in human liver microsomes was shown to be exclusively catalyzed by CYP3A enzymes. Evidence for in vivo metabolic activation of zafirlukast was obtained when the same GSH adduct was detected in bile of rats given an iv or oral dose of the drug. On the basis of results with model peroxidases and of the structures of product alcohols from incubations containing H2(18)O, it appeared that zafirlukast underwent dehydrogenation by two sequential one-electron oxidations. In addition, zafirlukast proved to be a mechanism-based inhibitor of CYP3A4 activity in human liver microsomes and in microsomes containing cDNA-expressed CYP3A4. The enzyme inhibitory property of zafirlukast was selective for this enzyme among all of the P450 enzymes that were tested in human liver microsomes. The inactivation was characterized by a K(I) of 13.4 microM and k(inact) of 0.026 min(-1). In summary, zafirlukast dehydrogenation to an electrophilic alpha,beta-unsaturated iminium intermediate may be associated with idiosyncratic hepatotoxicity and/or cause drug-drug interactions through inactivation of CYP3A4.
Silicon-resonator-based, 3&#x00B5;A real-time clock with &#x00B1;5ppm frequency accuracy (2009)

This paper bridges the gap with the demonstration of a generic ultra-low power thermal compensation concept applied to a low frequency piezoelectric AIN-driven silicon resonator [1 ] that can be used to implement both a RTC and a reference for a MEMS-based frequency synthesizer architecture eliminating the need for any other bulky reference.
Improvement of accuracy in digital holography by use of multiple holograms (2006)

Speckle pattern decorrelation reduces the accuracy of interferometric shape and deformation measurements. We introduce a technique for the reduction of speckle noise in digital holography. The method is not based on classical filtering techniques such as median filters. Instead it utilizes the shift theorem of the Fourier transform. For this method several holograms of the same object under test are recorded. The reconstruction leads to a set of object wave fields with different speckle patterns. A proper averaging procedure, taking into account the properties of the wrapped phases, leads to an improvement of the accuracy in the resulting phase difference. The theory of the applied method is described and our first results for technical components with an improvement of accuracy up to 1/57 of the wavelength are presented.
Pädagogische Absichten und ihre Aushandlung – eine symboltheoretische Skizzierung des sozialpädagogischen Handlungsraums (2008)

Gegenstand der folgenden Betrachtung ist die Mikroanalyse einer (sozial-) pädagogischen Interaktionssequenz aus einer Beratungsstelle. Ausgangspunkt ist die Annahme, dass professionelle Handlungsentwürfe nicht 1:1 von der ratsuchenden Klientel übernommen werden. Erkenntnisleitend ist die Frage, "wie" sich der wechselseitige Aushandlungsprozess zwischen den Akteur/inn/en gestaltet. Um diese Frage beantworten zu können, wähle ich einen psychoanalytisch orientierten Zugang (Tiefenhermeneutik). Mein Fokus liegt auf Handlungsmustern, die entweder unterhalb der Sprachpraxis liegen oder zwischen den Zeilen in metaphorischen Formen ausgeführt werden. Ausgehend von Inszenierungen der Klientel, die teilweise den Rahmen des pädagogischen Handlungsraums sprengen, werden sinnlich-symbolische Entwürfe konstruiert, die schließlich in sprachlich gefasste Äußerungen transformiert und erst dann im Beratungskontakt kommuniziert werden können. Den wechselseitigen Aushandlungsprozess fasse ich als Symbolbildungsprozess. Die gebildeten Konstruktionsformen werden in einem Stufenmodell nachgezeichnet und bedingen die spezifische Intermediarität des sozialpädagogischen Handlungsraums. URN: urn:nbn:de:0114-fqs0801523
Prominent and Persistent Extraneural Infection in Human PrP Transgenic Mice Infected with Variant CJD (2008)

Our findings emphasize the possibility that human-to-human transmission of vCJD might produce alternative neuropathological phenotypes and that lymphoid tissue examination of CJD cases classified as sporadic might reveal an infection by vCJD-type prions. They also provide evidence for the strong propensity of this agent to establish long-lasting, subclinical vCJD infection of lymphoreticular tissues, thus amplifying the risk for iatrogenic transmission.
Solvent Fractionation of Lignin (2014)

Lignin is a highly abundant source of renewable carbon that can be considered as a valuable sustainable source of biobased materials. The major issues for the commercial production of value added high performance lignin products are lignin’s physical and chemical heterogenities. To overcome these problems, a variety of procedures have been developed to produce pure lignin suitable for high performace applications such as lignin-derived carbon materials. However, most of the isolation procedures affect lignin’s properties and structure. In this chapter, a short review of the effect of solvent fractionation on lignin’s properties and structure is presented.