gebhart/patrepeval huggingface dataset:
Digital down conversion in software radio terminals (2000)

The idea of software radio requires an expansion of digital signal processing towards the antenna. Hence, for converting the received signal to baseband, the need of efficient high speed digital down converters arises. In [1] digital down conversion was identified as one of the ’critical functionalities’ because it has to run at a relative high sample rate, and has to provide high resolution. The common approach for digital down conversion (DDC) is the so called ROM table approach where the samples of the input signal are multiplied with amplitude values of the sine- and cosine-function stored in ROM. To achieve high resolution this technique requires a large look-up table which means large chip area, high power consumption, lower speed, and increased costs. In this paper a CORDIC-based digital down converter is described. It enables to reduce the size of the look-up table considerably. Additionally to previous publications, this paper provides an overall worst case quantization error estimation that facilitates the dimensioning of the CORDIC-DDC. 1
Corroded Casing: Testing of Sealing Capability and Retrievability of a Swelling Elastomer Packer (2008)

Abstract Globally, many thousands of potentially productive oil and gas wells suffer internal corrosion due to H2S, CO2, and other produced gases and liquids. This limits their capability to provide a packer sealing area suitable for traditional mechanical production packers. Total E&P Qatar planned a recompletion using intelligent well technology in a well in which they expected to find some corrosion. Before initiating the recompletion, they investigated the use of alternative packer technology. Swelling elastomer packers have been used worldwide in many applications, but verification was required in this case to assess whether such packers would hold pressure in a corroded section of casing. In addition, testing was also was needed to assess whether the completion could be pulled in the event that it became necessary to retrieve the components from the well. A swellable packer with multiple cable feed-through was designed and manufactured to approximately two-thirds size of the originally specified packer. A sample of corroded casing, supplied by Total E&P Qatar, was used to build a test jig. The jig was equipped to simulate and record pressure, temperature, and other downhole conditions. Theoretical simulations were performed to assess the force required to overcome the anchoring forces applied by the swelled elastomer and were verified by a pull test. It is expected that with a reliable sealing mechanism for these older wells, technically and financially viable workovers and re-completions can be performed, thereby extending field life and adding to recoverable reserves. This paper describes the application and test procedures along with the verification and results of the testing performed.
The Attenuation of Sound Waves in Water by a Reverberation Method (1946)

Sound waves are set up in a spherical tank by a crystal driver attached to the tank wall. The pressure level is obtained by a crystal hydrophone mounted flush in the tank wall. The output of the hydrophone is amplified and applied to a high speed level recorder. Decay curves are obtained by stopping the source. The crystal source is energized by a band of thermal noise insuring that a number of modes of vibration will be excited simultaneously. The spherical enclosure minimizes the shear losses at the wall for radial modes of vibration. The air radiation losses are readily computed for these modes. The mass reactance of the tank wall greatly reduces the air radiation losses at 25 kilocycles. On the basis of preliminary data to be presented at the meeting, the method may prove of considerable value in the study of the effects of hydrosols on the attenuation of sound waves in water.
Optical Absorption Edge in GaAs and Its Dependence on Electric Field (1961)

Values of absorption constant covering the range 1 cm−1 to 104 cm−1 have been derived from transmission measurements made on single-crystal gallium arsenide. The absorption edge is very steep up to ∼4000 cm−1, where there is a knee beyond which the absorption increases relatively slowly with photon energy. The energy bands have been calculated using Kane's theory. From these a theoretical absorption curve has been obtained which shows very good agreement with the experimental data. Using semi-insulating material, it has been possible to measure the shift of the edge with applied electric field. The effect is small (∼200-μ ev shift for 5000-v/cm field) but is in good agreement with theory.
Enhancing Penicillin G Acylase Stability by Site-directed Mutagenesis. (2000)

To improve the stability of penicillin G acylase(PGA) from Bacillus megaterium, a three-dimensional model of B.megaterium PGA was constructed based on crystal structure of penicillin G acylase from E.coli using PMODELING program. The mutation of Lys at beta427 and 430 to Ala was predicted to enhance the stability of PGA in acidic or organic solvent environment. The results showed that 2 mutant PGA had similar specific activity and Km as the parent PGA. Their optimum pH dropped 0.5 pH units. The stability of Lys430Ala was enhanced obviously at pH 5.2. The half lives of Lys427Ala and Lys430Ala were improved by 60 % and 166 %, respectively, in comparison with the parent PGA.
QRS Detection Algorithm Using Savitzky-Golay Filter (2013)

Abstract: QRS part of an electrocardiogram (ECG) is physiologically important for cardiac disease detection and extraction of this waveform from the raw signal is an important part of ECG analysis. Pan Tompkins ’ algorithm of QRS detection is an established method for extraction of this part of ECG. In this paper, a modification has been done on Pan Tompkins ’ algorithm by using a Savitzky-Golay filter in place of the high pass filter and differentiator of Pan Tompkins’ algorithm. Then QRS detection of normal as well as diseased ECG has been done using both Pan Tompkins ’ algorithm and the modified algorithm developed in this work for comparison. Index Terms- electrocardiogram, QRS, Pan Tompkins’ algorithm, Savitzky-Golay filter
An object correlation and maneuver detection approach for space surveillance (2012)

Object correlation and maneuver detection are persistent problems in space surveillance and maintenance of a space object catalog. We integrate these two problems into one interrelated problem, and consider them simultaneously under a scenario where space objects only perform a single in-track orbital maneuver during the time intervals between observations. We mathematically formulate this integrated scenario as a maximum a posteriori (MAP) estimation. In this work, we propose a novel approach to solve the MAP estimation. More precisely, the corresponding posterior probability of an orbital maneuver and a joint association event can be approximated by the Joint Probabilistic Data Association (JPDA) algorithm. Subsequently, the maneuvering parameters are estimated by optimally solving the constrained non-linear least squares iterative process based on the second-order cone programming (SOCP) algorithm. The desired solution is derived according to the MAP criterions. The performance and advantages of the proposed approach have been shown by both theoretical analysis and simulation results. We hope that our work will stimulate future work on space surveillance and maintenance of a space object catalog.
Three stages of erythropoietic progenitor cell differentiation distinguished by a number of physical and biologic properties (1978)

Previous studies have shown that erythroid precursors at sequential stages of differentiation along the red cell pathway can be distinguished by differences in the size and maturation kinetics of the colonies to which they give rise in vitro. Using criteria based on these two parameters, it is thus possible to identify three distinct erythroid progenitor cell populations in the mouse, known as day 8 BFU-E, day 3 BFU-E, and CFU-E. These cell types have now been shown to differ in a number of other respects, including progenitor cell size, sensitivity to cycle-active agents, response to plethora, and effects of the W/Wv genotype. In addition, a comparison of the differences found between day 8 BFU-E and day 3 BFU-E on one hand and those distinguishing day 3 BFU-E and CFU-E on the other provides support for the view that early erythropoietic cell differentiation involves a series of changes that take place long before competence to synthesize hemoglobin becomes manifest.
Uranium ingot casting method with Uranium deposit in a Pyroprocessing (2010)

The uranium ingot casting process is one of the steps which consolidate uranium deposits produced by electrorefiner as an ingot form in a pryprocessing technique. This paper introduces new design concept of the ingot casting equipment and the performance test results of the lab-scale ingot casting equipment fabricated based on the design concept. Casting equipment produces the uranium ingot by pouring an uranium melt into a mold by tilting a melting crucible. Also it is equipped with a cup which is able to continuously feed uranium deposits into a melting crucible. The productivity could be significantly enhanced by introducing the continuous operation concept.
The Contribution of the Protestant Churches to Religious Liberty in Colonial America (1935)

While endeavouring to formulate these remarks I have come to suspect that there may possibly lurk in the title of my paper a misleading implication. The word “contribution” would seem to connote on the part of the Protestant churches a deliberate and concerted effort toward the triumph of religious liberty. Those of us who today prize ecclesiastical freedom would like to feel that our colonial ancestors of their own free will and choice undertook the march to liberty. Liberal-minded historians in particular are prone to sing the praises of this individual or that church for furthering this advance; they are inclined to gloss over or to apologize for the men and the institutions that hindered it.
New Strategies Using Handheld Augmented Reality and Mobile Learning-teaching Methodologies, in Architecture and Building Engineering Degrees (2013)

In this paper we present “ML-AR” Practice Modules, in the field of Architecture and Building Engineering. They are alternative to traditional courses which are taught over a semester, and adapted to the student learning flow. In this case we used a particular technology such as Hand Held Augmented Reality (HHAR), to overlap virtual models on real scenes. Experience was limited to specific groups within four areas of undergraduate and master. In each case, specific Mobile Learning (ML) practices have been carried out. Each experimental group (EG) has been able to visualize a virtual model created by them or their teachers, in order to evaluate an architectural proposal or a construction detail, on site, as part of their own learning process. Students without the required devices, still in the ordinary course, configured the control group, (CG). Virtual models generation and augmented scenes preview on site, provided evaluation tools for better assessment and knowledge of student's proposals prior to any intervention. In addition, tangible interaction and the abilitiy to modify and share their views also provided social skills and helped to create a self-formative process. Mobile devices and AR technology were used close to the students who show greater motivation and commitment in their didactic contents generation. Evaluation is based on academic performance improvement through study cases, by comparing the achievement of the overall objectives between the two groups (EG & GC). Relationship between performance and usability is also assessed. The experiments carried out confirmed our initial hypothesis, where Information and Communication Technologies (ICT) used in the web 3.0 environments, allow improving learning processes and reducing its temporality without previous experience at a very low cost. AR Technology in this area combined with Cloud computing development, creates a new paradigm of continuous training and self-learning though the use of AR technology.
Properties of <i>SEPT9</i> isoforms and the requirement for GTP binding (2004)

Members of the evolutionarily conserved septin family of genes are emerging as key components of several cellular processes including membrane trafficking, cytokinesis, and cell-cycle control events. SEPT9 has been shown to have a complex genomic architecture, such that up to 15 different isoforms are possible by the shuffling of five alternate amino termini and three alternate carboxy termini. Genomic and transcriptional alterations of SEPT9 have been associated with neoplasia. The present study has used a Sept9-specific antibody to determine the pattern of isoform expression in a range of tumour cell lines. Western blot analysis indicated considerable variation in the relative amounts and isoform content of Sept9. Immunofluorescence studies showed a range of patterns of cytoplasmic localization ranging from mainly particulate to mainly filamentous. Expression constructs were also generated for each amino terminal isoform to investigate the patterns of localization of individual isoforms and the effects on cells of ectopic expression. The present study shows that the epsilon isoform appears filamentous in this overexpression system while the remaining isoforms are particulate and cytoplasmic. Transient transfection of individual constructs into tumour cell lines results in cell-cycle perturbation with a G2/M arrest and dramatic growth suppression, which was greatest in cell lines with the lowest amounts of endogenous Sept9. Similar phenotypic observations were made with GTP-binding mutants of all five N-terminal variants of Sept9. However, dramatic differences were observed in the kinetics of accumulation of wild-type versus mutant septin protein in transfected cells. In conclusion, the present study shows that the expression patterns of Sept9 protein are very varied in a panel of tumour cell lines and the functional studies are consistent with a model of septin function as a component of a molecular scaffold that contributes to diverse cellular functions. Alterations in the levels of Sept9 protein by overexpression of individual isoforms can clearly perturb cellular behaviour and may thus provide a mechanistic explanation for observations of deranged septin expression in neoplasia.
Organoboron reagents and recent strategies in rhodium catalysed additions (2011)

The COOH terminus of decay accelerating factor (DAF) contains a signal that directs attachment of a glycophosphatidylinositol (GPI) membrane anchor in a process involving proteolytic removal of 17-31 COOH-terminal residues. Previous work suggested that two elements are required for anchor addition, a COOH-terminal hydrophobic domain (the GPI signal) and an element located NH2-terminal to it, postulated to be the cleavage/attachment site. Using [3H]ethanolamine (a component of the anchor) to tag the COOH terminus, we isolated and sequenced a COOH-terminal tryptic peptide, thereby identifying Ser-319 as the COOH-terminal residue attached to the GPI anchor. This indicates that a 28-residue peptide is removed during processing and localizes the cleavage/attachment site precisely to the region previously shown to be required for anchor attachment (between 10 and 20 residues NH2-terminal to the hydrophobic domain). Since DAF contains multiple cryptic cleavage/attachment sites, we used a GPI-linked human growth hormone-DAF fusion to study the structural requirements for cleavage/attachment. Our results show that while sequences immediately NH2-terminal to the attachment site are not required for anchor addition, deletion of Ser-319 abolishes both anchor attachment and transport to the cell surface. Systematic replacement of the attachment site serine with all possible amino acids indicated that alanine, aspartate, asparagine, glycine, or serine efficiently support GPI anchor attachment while valine and glutamate are partially effective. All other substitutions including cysteine (permitted at the attachment site in other GPI-anchored proteins) abolish both GPI anchor attachment and transport to the cell surface, resulting in accumulation of uncleaved fusion protein in internal compartments (endoplasmic reticulum and Golgi). These results support the general rule that the residue at the cleavage/attachment site must be small. Further, addition of a GPI anchor appears to be necessary for transport to the cell surface in transfected COS cells.
Inhibition of Neuroinflammation Prevents Injury to the Serotonergic Network After Hypoxia-Ischemia in the Immature Rat Brain (2010)

The phenotypic identities and characterization of neural networks disrupted after neonatal hypoxia-ischemia (HI) in the preterm brain remain to be elucidated. Interruption of the central serotonergic (5-hydroxytryptamine [5-HT]) system can lead to numerous functional deficits, many of which match those in human preterm neonates exposed to HI. How the central serotonergic network is damaged after HI and mechanisms underlying such injury are not known. We used a Postnatal Day 3 rat model of preterm HI and found parallel reductions in the 5-HT transporter expression, 5-HT levels and numbers of 5-HT-positive dorsal raphe neurons 1 week after insult. Post-HI administration of minocycline, an inhibitor of activated microglia, attenuated HI-induced damage to the serotonergic network. Minocycline effects seemed to be region specific, that is, where there was micro-glial activation and increases in tumor necrosis factor-α and inter-leukin 1β. The concurrent improvement in serotonergic outcomes suggests that inhibition of neuroinflammation prevented damage to the serotonergic neurons rather than affected the regulation of 5-HT or serotonin transporter. These data elucidate the mechanisms of serotonergic network injury in HI, and despite the known adverse effects associated with the use of minocycline in neonates, postinsult administration of minocycline may represent a novel approach to counter neuroinflammation and preserve the integrity of the central serotonergic network in the preterm neonate.
Yield trend estimation in the presence of non-constant technological change and weather effects (2012)

The application of yield time series in risk analysis prerequisites the estimation of technological trend which might be present in the data. In this paper, we show that in presence of highly volatile yield time series and non-constant technology, the consideration of the weather effect in the trend equation can seriously improve trend estimation results. We used ordinary least squares (OLS) and MM, a robust estimator. Our empirical analysis is based on weather data as well as farm-level and county-level yield data for a sample of grain-producing farms in Kazakhstan.
Using direct electrochemistry to probe rate limiting events during nitrate reductase turnover (2000)

Protein film voltammetry of NarGH catalysing nitrate reduction under steady state conditions provides information on events occurring within the enzyme during the catalytic cycle. In this discussion we have focused on exploring the ability of two simple catalytic schemes to reproduce the voltammetric response of NarGH; electron transfer to the enzyme's active site being described either by interfacial electron exchange (Scheme 1) or intramolecular electron delivery via the operation of an electron relay centre (Scheme 2). When the two electron reduced, catalytically competent active site of the enzyme is generated from the oxidised form in 'rapid', non-rate limiting steps of the catalytic cycle, the voltammetric behaviour of NarGH cannot be reproduced. Rather under all the conditions investigated, one electron reduction of the active site from a semi-reduced to a fully-reduced state is found to be crucial to progression through the enzyme's catalytic cycle. The catalytically relevant semi- and fully-reduced oxidation states of the NarGH active site are most likely to correspond to the Mo(V) and Mo(IV) states of the Mo(MGD)2 centre, respectively, although it is not possible to rule out the possibility that they correspond to molybdopterin based oxidation states as observed in other enzymes. We suggest that the rate of either conformational rearrangement within the semi-reduced active site or intramolecular electron delivery to the active site constitutes a defining feature in the catalytic cycle of NarGH and results in the napp approximately 1 appearance of the catalytic waveform.
Tessellation of plane with magnetic landmarks for pose control and global localisation (2010)

Proposed are regular tessellations of the plane environment where various patterns of magnetic landmarks are arranged in repeated configurations for fine pose tracking control and global localisation of mobile robots. Mobile robots sense the magnetic field with embedded magnetic Hall sensors and can recognise the pattern of the landmark. In the experiments, the accuracy of pose control of a mobile robot with 140 mm diameter is less than 0.5 mm in the position and less than 0.5° in the orientation. Also, the experimental results of landmark recognition demonstrate that the proposed method is suitable for a practical solution to the global localisation in engineered environments.
Effect of Omega-3 Fatty Acids, Lutein/Zeaxanthin, or Other Nutrient Supplementation on Cognitive Function (2015)

clinicaltrials.gov Identifier: NCT00345176.