gebhart/patrepeval huggingface dataset:
Nonlinear System Identification for Horn Loudspeakers (1996)

For small amplitudes the dominant nonlinear mechanisms in horn loudspeakers can be modeled by a special class of polynomial systems known as S M systems. This model is tested on a real horn loudspeaker, and unknown model parameters are determined by system identification. A novel identification technique is presented which is based on the partial measurement of the higher order system functions with a steady-state excitation signal. The amplitude and phase responses of the linear subsystems in the S M system are estimated from the system functions by linear regression. The results of the system identification give qualitative clues about the dominant nonlinearities as well as quantitative estimates of relevant parameters of the loudspeaker model. This information is valuable for improving the design of horn loudspeakers and for developing nonlinear correction filters to compensate for the nonlinearities in the loudspeaker and thus reduce the distortion in the radiated sound by preprocessing the electric input signal.
Fragment Based Drug Discovery: Practical Implementation Based on 19F NMR Spectroscopy (2011)

Fragment based drug discovery (FBDD) is a widely used tool for discovering novel therapeutics. NMR is a powerful means for implementing FBDD, and several approaches have been proposed utilizing (1)H-(15)N heteronuclear single quantum coherence (HSQC) as well as one-dimensional (1)H and (19)F NMR to screen compound mixtures against a target of interest. While proton-based NMR methods of fragment screening (FBS) have been well documented and are widely used, the use of (19)F detection in FBS has been only recently introduced (Vulpetti et al. J. Am. Chem. Soc.2009, 131 (36), 12949-12959) with the aim of targeting "fluorophilic" sites in proteins. Here, we demonstrate a more general use of (19)F NMR-based fragment screening in several areas: as a key tool for rapid and sensitive detection of fragment hits, as a method for the rapid development of structure-activity relationship (SAR) on the hit-to-lead path using in-house libraries and/or commercially available compounds, and as a quick and efficient means of assessing target druggability.
Hydrogen peroxide generated extracellularly by receptor–ligand interaction facilitates cell signaling (2005)

Reactive oxygen species (ROS) are key components of postreceptor intracellular signaling pathways; however, the role of ROS in signal initiation is uncertain. We discovered that receptor-ligand interaction caused the generation of hydrogen peroxide (H2O2). Using members of the hematopoietin receptor superfamily, as well as EGF receptor, we show that H2O2 is generated by specific receptor-ligand interaction in cells and in cell-free systems. With cognate ligand, the extracellular domain of the receptor was sufficient for H2O2 generation. We also found that production of H2O2 was diminished in a granulocyte-macrophage colony-stimulating factor receptor mutant unable to bind ligand. Exogenously added H2O2 induced signaling in the absence of ligand, whereas catalase and a membrane-bound peroxiredoxin inhibited ligand-dependent signaling. Our results suggest that H2O2 produced by receptor-ligand interaction is involved as a chemical mediator that facilitates cell signaling.
Ultrathin Planar Cavity Metasurfaces (2018)

An ultrathin planar cavity metasurface is proposed based on ultrathin film interference and its practicability for light manipulation in visible region is experimentally demonstrated. Phase of reflected light is modulated by finely adjusting the thickness of amorphous silicon (a-Si) by a few nanometers on an aluminum (Al) substrate via nontrivial phase shifts at the interfaces and interference of multireflections generated from the planar cavity. A phase shift of π, the basic requirement for two-level phase metasurface systems, can be accomplished with an 8 nm thick difference. For proof of concept, gradient metasurfaces for beam deflection, Fresnel zone plate metalens for light focusing, and metaholograms for image reconstruction are presented, demonstrating polarization-independent and broadband characteristics. This novel mechanism for phase modulation with ultrathin planar cavity provides diverse routes to construct advanced flat optical devices with versatile applications.
3D Simulation of Flapping Flags in a Uniform Flow by The Immersed Boundary Method (2007)

We present an immersed boundary (IB) method for 3D simulation of flappingflags in a uniform flow. The proposed formulation is manipulated on the basis of an efficient Navier-Stokes solver adopting the fractional step method and a staggered Cartesian grid system. A direct numerical method is developed to calculate the flag motion, with the elastic force treated implicitly. The fluid motion defined on an Eulerian grid and the flag motion defined on a Lagrangian grid are independently solved and the mass of flag is handled in a natural way. An additional momentum forcing is formulated from the flag motion equation in a way similar with the direct-forcing IB formulation and acts as the interaction force between the flag and ambient fluid. A series of numerical tests are performed and the present results are compared qualitatively and quantitatively with previous studies. The instantaneous flag motion is analyzed under different conditions and surrounding vortical structures are identified. The effects of physical parameters on the flapping frequency are studied.
Scanometric DNA Array Detection with Nanoparticle Probes* (2020)

A method for analyzing combinatorial DNA arrays using oligonucleotide-modified gold nanoparticle probes and a conventional flatbed scanner is described here. Labeling oligonucleotide targets with nanoparticle rather than fluorophore probes substantially alters the melting profiles of the targets from an array substrate. This difference permits the discrimination of 1446an oligonucleotide sequence from targets with single-nucleotide mismatches with a selectivity that is over three times that observed for fluorophore-labeled targets. In addition, when coupled with a signal amplification method based on nanoparticle-promoted reduction of silver(I), the sensitivity of this scanometric array detection system exceeds that of the analogous fluorophore system by two orders of magnitude.
The Virtual Naval Hospital: A Digital Library for Naval Primary Care Providers and Patients (1998)

The technical feasibility of delivering a digital library of medical information to the deckplates was proven. The digital library will realize its potential when satellite-based access to the Internet becomes available. In the interim, the digital library will also be distributed on CD-ROM.
In-depth distribution of ion irradiation defects evaluated by mobility of Al0.3Ga0.7As/GaAs two-dimensional electron gas (1992)

It has been found that the low-temperature (&amp;lt;100 K) mobility of two-dimensional electron gas is a sensitive and quantitative measure for ion irradiation defects. With this technique, the depth distribution of defects resulting from 10-keV Ar ion irradiation (projected range=8.8 nm) to doses of 0.3–6.78×1011/cm2 onto Al0.3Ga0.7As/GaAs heterostructures was evaluated at depth of 60–120 nm. The distribution, which was estimated by reciprocal of mobility, has been found to be exponential with a 1/e penetration length of 20 nm for irradiation temperatures of 85–90 K and 16 nm for room temperature. From this result, it is suggested that the cause of defect penetration in deep regions is the ion channeling.
Electrical Field Enhancement in Carbon Nanotube-Based Electron Field Cathodes (2010)

The problem of evaluating the field amplification factor in electron field emitters on the basis of carbon nanotubes (CNT) has been considered. The electrostatic problem of determination of the field amplification factor for CNTs having various structures of the tip, depending on the tilting angle in regard to the cathode plane as well as on the inter-electrode distance, has been resolved. The dependence of the field amplification factor for vertically aligned CNTs comprising an array on the intertube distance has been obtained. This dependence is used for evaluation of the optimal surface density of CNTs in the array providing the maximum emission current density. The current-voltage characteristic of an array calculated with taking into account the statistical spread of the orientation angle of CNTs is compared with that obtained recently with taking into account a spread in geometrical parameters of CNTs.
Electric Conduction in a Single GaN Nanocolumn (2012)

We study electric conduction of single GaN nanocolumns, which are synthesized by rf-plasma-assisted molecular beam epitaxy. We attach Ti/Al electrodes to a single GaN nanocolumn on SiO2/Si substrate by using photolithography, and we succeed in creating the ohmic contacts. We observe the nonlinear conduction at large currents and low temperatures. The temperature dependence of resistivity represents the activation-type one with an activation energy of about 11 meV due to donor levels at high temperatures. At low temperatures, it shows the Mott variable-range hopping conduction. We find a strong positive magnetoresistance effect at low temperatures. [DOI: 10.1380/ejssnt.2012.355]
Novel Machado-Joseph disease-modifying genes and pathways identified by whole-exome sequencing (2021)

Machado-Joseph disease (MJD/SCA3) is a neurodegenerative polyglutamine disorder exhibiting a wide spectrum of phenotypes. The abnormal size of the (CAG)n at ATXN3 explains ~55% of the age at onset variance, suggesting the involvement of other factors, namely genetic modifiers, whose identification remains limited. Our aim was to find novel genetic modifiers, analyse their epistatic effects and identify disease-modifying pathways contributing to MJD variable expressivity. We performed whole-exome sequencing in a discovery sample of four age at onset concordant and four discordant first-degree relative pairs of Azorean patients, to identify candidate variants which genotypes differed for each discordant pair but were shared in each concordant pair. Variants identified by this approach were then tested in an independent multi-origin cohort of 282 MJD patients. Whole-exome sequencing identified 233 candidate variants, from which 82 variants in 53 genes were prioritized for downstream analysis. Eighteen disease-modifying pathways were identified; two of the most enriched pathways were relevant for the nervous system, namely the neuregulin signaling and the agrin interactions at neuromuscular junction. Variants at PARD3, NFKB1, CHD5, ACTG1, CFAP57, DLGAP2, ITGB1, DIDO1 and CERS4 modulate age at onset in MJD, with those identified in CFAP57, ACTG1 and DIDO1 showing consistent effects across cohorts of different geographical origins. Network analyses of the nine novel MJD modifiers highlighted several important molecular interactions, including genes/proteins previously related with MJD pathogenesis, namely between ACTG1/APOE and VCP/ITGB1. We describe novel pathways, modifiers, and their interaction partners, providing a broad molecular portrait of age at onset modulation to be further exploited as new disease-modifying targets for MJD and related diseases.
geographies, yearnings, identities (2006)

This is a PDF version of the book geographies, yearnings, identities published by University of Chester / Fiesol e Arte ©Maggie Jackson &amp; Chris Bebbington 2006.
Tunable wavelength spacing multi-wavelength ring laser using programmable DGD module as intra-cavity filter (2004)

A multi-wavelength fibre laser whose channel spacing can be dynamically and continuously tuned is demonstrated experimentally. A novel programmable magneto-optic-based DGD module is used as the intra-cavity optical filter to control the wavelength spacing. Channel spacing tunable from 0.4 to 1.6 nm is achieved.
SleepMore (2022)

The availability of commercial wearable trackers equipped with features to monitor sleep duration and quality has enabled more useful sleep health monitoring applications and analyses. However, much research has reported the challenge of long-term user retention in sleep monitoring through these modalities. Since modern Internet users own multiple mobile devices, our work explores the possibility of employing ubiquitous mobile devices and passive WiFi sensing techniques to predict sleep duration as the fundamental measure for complementing long-term sleep monitoring initiatives. In this paper, we propose SleepMore, an accurate and easy-to-deploy sleep-tracking approach based on machine learning over the user's WiFi network activity. It first employs a semi-personalized random forest model with an infinitesimal jackknife variance estimation method to classify a user's network activity behavior into sleep and awake states per minute granularity. Through a moving average technique, the system uses these state sequences to estimate the user's nocturnal sleep period and its uncertainty rate. Uncertainty quantification enables SleepMore to overcome the impact of noisy WiFi data that can yield large prediction errors. We validate SleepMore using data from a month-long user study involving 46 college students and draw comparisons with the Oura Ring wearable. Beyond the college campus, we evaluate SleepMore on non-student users of different housing profiles. Our results demonstrate that SleepMore produces statistically indistinguishable sleep statistics from the Oura ring baseline for predictions made within a 5% uncertainty rate. These errors range between 15-28 minutes for determining sleep time and 7-29 minutes for determining wake time, proving statistically significant improvements over prior work. Our in-depth analysis explains the sources of errors.
Power of deep, all-exon resequencing for discovery of human trait genes (2009)

The ability to sequence cost-effectively all of the coding regions of a given individual genome is rapidly approaching, with the potential for whole-genome resequencing not far behind. Initiatives are currently underway to phenotype hundreds of thousands of individuals for major human traits. Here, we determine the power for de novo discovery of genes related to human traits by resequencing all human exons in a clinical population. We analyze the potential of the gene discovery strategy that combines multiple rare variants from the same gene and treats genes, rather than individual alleles, as the units for the association test. By using computer simulations based on deep resequencing data for the European population, we show that genes meaningfully affecting a human trait can be identified in an unbiased fashion, although large sample sizes would be required to achieve substantial power.
Verification of characteristic basis function method using fast far-field approximation (2016)

In this paper, we evaluate the fast far-field approximation (FaFFA) for the characteristic basis function method (CBFM). By adopting the FaFFA to the CBFM, impedance matrix calculation time can be accelerated. We calculate the radar cross section of the conductor plate with the use of FaFFA-CBFM, and compare the results with ordinary-CBFM. Both results are in good agreement, and FaFFA-CBFM is faster than the conventional method.
On the Mechanism of Reaction of Radicals with Tirapazamine (2007)

Ketyl radicals produced by photolysis of ketones or di-tert-butyl peroxide (DTBP) in alcohol solvents react rapidly with tirapazamine (TPZ). The acetone ketyl radical (ACOH) reacts with TPZ with an absolute second-order rate constant of (9.7 +/- 0.4) x 108 M-1 s-1. The reaction kinetics can be followed by monitoring the bleaching of TPZ absorption at 475 nm or the formation of a reaction product which absorbs at 320 and 410 nm. The ACOD radical reacts with TPZ in 2-propanol-OD with an absolute rate constant of (6.7 +/- 0.5) x 108 M-1 s-1, corresponding to a kinetic isotope effect (KIE) of 1.4. Deuteration of the radical on carbon (ACOH-d6) retards the reaction of the radical with TPZ even further (absolute rate constant = (4.8 +/- 0.04) x 108 M-1 s-1). This result corresponds to a KIE of 2.0. Radicals derived from dioxane and diisopropyl ether by flash photolysis of DTBP in ethereal solvent react with TPZ more slowly than do ketyl radicals. It is concluded that ketyl radicals react, in part, with TPZ in organic solvents by transfer of a hydrogen atom from the OH and CH3 groups of the ketyl radical to the oxygen atom at the N4 position of TPZ to form acetone or acetone enol and a radical derivative of TPZ (TPZH). The latter species absorbs at 320 and 405 nm, has a lifetime of hundreds of microseconds in alcohol solvents, and decays by disproportionation to form TPZ and a reduced heterocycle. The reduced heterocycle eventually forms a desoxytirapazamine by a polar mechanism. The results are supported by density functional theory calculations. It is proposed that dioxanyl radical will also react, in part, with TPZ by transfer of a hydrogen atom from the carbon adjacent to the radical center to the oxygen atom at the N4 position of TPZ. This produces the enol ether and the previously mentioned TPZH radical. It is further posited that ether radicals react a bit more slowly than ketyl radicals because they lack the second mode of hydrogen transfer (from the OH group) that is present in the ACOH radical. Our data are permissive of the possibility that ether radicals add to TPZ at a rate that is competitive with beta-hydrogen atom transfer.
An Event Horizon Imager (EHI) Mission Concept Utilizing Medium Earth Orbit Sub-mm Interferometry (2021)

Submillimeter interferometry has the potential to image supermassive black holes on event horizon scales, providing tests of the theory of general relativity and increasing our understanding of black hole accretion processes. The Event Horizon Telescope (EHT) performs these observations from the ground, and its main imaging targets are Sagittarius A<sup>*</sup> in the Galactic Center and the black hole at the center of the M87 galaxy. However, the EHT is fundamentally limited in its performance by atmospheric effects and sparse terrestrial (<i>u</i>,<i>v</i>)-coverage (Fourier sampling of the image). The scientific interest in quantitative studies of the horizon size and shape of these black holes has motivated studies into using space interferometry which is free of these limitations. Angular resolution considerations and interstellar scattering effects push the desired observing frequency to bands above 500 GHz.<br/>This paper presents the requirements for meeting these science goals, describes the concept of interferometry from Polar or Equatorial Medium Earth Orbits (PECMEO) which we dub the Event Horizon Imager (EHI), and utilizes suitable space technology heritage. In this concept, two or three satellites orbit at slightly different orbital radii, resulting in a dense and uniform spiral-shaped (<i>u</i>,<i>v</i>)-coverage over time. The local oscillator signals are shared via an inter-satellite link, and the data streams are correlated on-board before final processing on the ground. Inter-satellite metrology and satellite positioning are extensively employed to facilitate the knowledge of the instrument position vector, and its time derivative. The European space heritage usable for both the front ends and the antenna technology of such an instrument is investigated. Current and future sensors for the required inter-satellite metrology are listed. Intended performance estimates and simulation results are given.
System including a direct contact desublimating heat exchanger for reducing fouling (2023)

A process to prevent fouling using a desublimating heat exchanger is disclosed. An outlet stream from the desublimating heat exchanger may be split into a plurality of parallel streams. The parallel streams may be sent through other devices for performing a unit operation, and the devices for performing a unit operation may change the temperature of at least one of the parallel streams. Parallel streams of differing temperature may emerge from the devices for performing a unit operation. The parallel streams of differing temperature may be sent to a mixing chamber. A mixed stream of uniform temperature may emerge from the mixing chamber, and the mixed stream may be recycled back to the desublimating heat exchanger. The mixing chamber may be separate from the desublimating heat exchanger, or the parallel streams of differing temperature may be mixed in the desublimating heat exchanger.
The properties of resonant transmission in triple-barrier/double-quantum-well heterostructures (1992)

To understand the nature of resonant tunneling in triple-barrier/double-quantum-well structures, we have investigated the properties of transmission probability TT of such structures with use of the transfer-matrix method. The transfer matrix of the middle barrier is calculated to analyze the amplitude decay, the phase shift, and the coupling effects that are induced between the two quantum wells. The dependencies of TT and the splitting of the resonant peaks on the middle-barrier thickness, the well width, and the symmetry of the structures are calculated. The origin of the transmission resonance and the resonant condition for symmetric (equal well widths) and asymmetric structures are discussed. The variations of TT with the applied voltage are also analyzed. The calculation results lead to some suggestions on how to design triple-barrier structures with improved performance.
WormBase: a modern Model Organism Information Resource (2019)

WormBase (https://wormbase.org/) is a mature Model Organism Information Resource supporting researchers using the nematode Caenorhabditis elegans as a model system for studies across a broad range of basic biological processes. Toward this mission, WormBase efforts are arranged in three primary facets: curation, user interface and architecture. In this update, we describe progress in each of these three areas. In particular, we discuss the status of literature curation and recently added data, detail new features of the web interface and options for users wishing to conduct data mining workflows, and discuss our efforts to build a robust and scalable architecture by leveraging commercial cloud offerings. We conclude with a description of WormBase's role as a founding member of the nascent Alliance of Genome Resources.
What Defines Walkability: Walking Behavior Correlates (2019)

At one point in time, cities grew as compact and vibrant entities focused on the downtown. In these close-knit environments, residents had the ability to walk or bicycle to destinations due to the fact that they lived in close proximity to where they worked and entertained. However, as development patterns slowly changed, cities began to sprawl outward causing an automobile dominated society that has lead to a number of negative effects, including traffic congestion and increased sedentary lifestyles. Due to these problems, the city planning and public health professions are now supporting walkable communities that are designed to promote walking and bicycling to nearby destinations. However, the implementation of walkability in an environment has been hindered by the fact that planners and public health practitioners have not adequately determined what measurable variables define walkability. While a number of studies and reports have attempted to define walkability, there are few occasions when similarities exist. Further complicating the task of defining walkability is the difficulty that exists in identifying the strongest correlates of walking. The objective of this paper is to examine the literature focused on walkability and the walking behavior to decipher a compact list of proxy variables from those cited in research that can serve as a working definition of walkability. A synthesis of the literature will also determine if walkability actually produces an increase in walking, and whether this increase is for transportation or recreational purposes. As a result of the findings from these research questions and the literature reviewed in this paper, recommendations for future actions for planners are proposed to help improve the implementation of walkability in the built environment.