gebhart/patrepeval huggingface dataset:
On the Efficient Estimation of Min-Entropy (2020)

The min-entropy is a widely used metric to quantify the randomness of generated random numbers in cryptographic applications; it measures the difficulty of guessing the most likely output. An important min-entropy estimator is the compression estimator of NIST Special Publication (SP) 800-90B, which relies on Maurer's universal test. In this paper, we propose two kinds of min-entropy estimators to improve computational complexity and estimation accuracy by leveraging two variations of Maurer's test: Coron's test (for Shannon entropy) and Kim's test (for Renyi entropy). First, we propose a min-entropy estimator based on Coron's test. It is computationally more efficient than the compression estimator while maintaining the estimation accuracy. The secondly proposed estimator relies on Kim's test that computes the Renyi entropy. This estimator improves estimation accuracy as well as computational complexity. We analytically characterize the bias-variance tradeoff, which depends on the order of Renyi entropy. By taking into account this tradeoff, we observe that the order of two is a proper assignment and focus on the min-entropy estimation based on the collision entropy (i.e., Renyi entropy of order two). The min-entropy estimation from the collision entropy can be described by a closed-form solution, whereas both the compression estimator and the proposed estimator based on Coron's test do not have closed-form solutions. By leveraging the closed-form solution, we also propose a lightweight estimator that processes data samples in an online manner. Numerical evaluations demonstrate that the first proposed estimator achieves the same accuracy as the compression estimator with much less computation. The proposed estimator based on the collision entropy can even improve the accuracy and reduce the computational complexity.
Method for leveling the signal-to-noise ratio in multichannel functional near-infrared spectroscopy (2017)

The difference in signal-to-noise ratio (SNR) within functional near-infrared spectroscopic (fNIRS)-measurement channels makes it difficult to compare the significance of the signal amplitude in an individual channel against the baseline or against signals in other channels. The difference in SNR mainly originates from the difference in light loss due to the hair coverage or the optode–scalp contact. During the initial calibration of most commercial fNIRS equipment, the detected signals in different channels are differently amplified such that the system effectively utilizes a dynamic range for measurement. While different amplification rates among the channels realize almost equal signal intensities, they also differently amplify the detection noises. This results in different apparent noises in the fNIRS signals between channels. In order to level the SNRs in all the measurement channels, the system needs to equalize the light intensities received by the detectors instead of changing the signal amplification rates. To realize this novel procedure for leveling the SNR among the channels, we developed an fNIRS system equipped with an optical attenuator at each source and detector. A systematic procedure for modulating the attenuators to level SNR over all channels was mathematically formulated, and the procedure was examined using an optical phantom with a surface covered with air.
Polymer latexes for cell-resistant and cell-interactive surfaces (2000)

Novel polymer latexes were prepared that can be applied in several ways for the control and study of cell behavior on surfaces. Acrylic latexes with glass transitions ranging from -30 to 100 degrees C were synthesized by dispersion polymerization in a water and alcohol solution using an amphiphilic comb copolymer as a stabilizing agent. The comb had a poly(methyl methacrylate) backbone and hydrophilic poly(ethylene glycol) (PEG) side chains, which served to stabilize the dispersion and create a robust hydrophilic coating on the final latex particles. The end groups of the comb stabilizer can be selectively functionalized to obtain latex particles with a controlled density of ligands tethered to their surfaces. Latexes were prepared with adhesion peptides (RGD) linked to the surface of the acrylic beads to induce attachment and spreading of cells. Coalesced films obtained from the RGD-bearing latex particles promoted attachment of WT NR6 fibroblasts, while films from unmodified latex particles were resistant to these cells. Additionally, RGD-linked beads were embedded in cell-resistant comb polymer films to create cell-interactive surfaces with discrete clustered-ligand domains. Cell attachment and morphology were seen to vary with the surface density of the RGD-bearing latex beads.
Area x‐ray beam equalization for digital angiography (1999)

An area beam equalization technique has been investigated in order to generate patient-specific compensating filters for digital angiography. An initial image was used to generate the compensating filter, which was fabricated using a deformable compensating material, containing CeO2, and an array of square pistons. The CeO2 attenuator thicknesses were calculated using the gray level information from the initial unequalized image. The array of pistons was pressed against a uniform thickness of attenuating material to generate a filter for x-ray beam equalization. The filter was subsequently inserted into the x-ray beam for the final equalized radiograph. It was positioned close to the focal spot (magnification of 8.0) in order to minimize edge artifacts from the filter. The equalization of x-ray transmission across the field exiting from the object significantly improved the image quality by preserving local contrast throughout the image. The contrast-to-noise ratio (CNR) in the equalized images was increased-by up to fivefold. Phantom studies indicate that equalized images using a relatively small array of pistons (e.g., 8 x 8) produce significant improvement in image quality with negligible perceptible artifacts. Animal studies showed that beam equalization significantly improved fluoroscopic and angiographic image quality. X-ray beam equalization produced an image with a relatively uniform scatter-glare intensity and it reduced the scatter-glare fraction in the previously underpenetrated region of the image from 0.65 to 0.50. Also, x-ray tube loading due to the mask assembly itself was negligible. In conclusion, area beam equalization reduces the scatter-glare fraction and significantly improves CNR in the previously underpenetrated region of the image.
3D salt‐flank imaging with transmitted arrival VSP data (2009)

PreviousNext No AccessSEG Technical Program Expanded Abstracts 20093D salt‐flank imaging with transmitted arrival VSP dataAuthors: Mark A. RobertsBrian E. HornbyFrancis RollinsMark A. RobertsBP, Brian E. HornbyBP, and Francis RollinsBPhttps://doi.org/10.1190/1.3255734 SectionsSupplemental MaterialAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract A 3D wave‐equation migration algorithm has been developed to image salt flanks with transmitted arrival VSP data. A precise knowledge of the salt flank location is often essential for accurate resource estimates and optimal well planning. The traditional salt‐proximity survey provides a poorly constrained line in 3D space. In this abstract we develop a method to image the full salt surface by utilizing long‐offset walk‐away and 3D VSP datasets that are frequently acquired for imaging purposes. The method has been successfully demonstrated on a real data example.Permalink: https://doi.org/10.1190/1.3255734FiguresReferencesRelatedDetailsCited ByVelocity model building for single-offset VSP data via deformable-layer tomography: A Texas salt dome exampleYukai Wo, Jingjing Zong, Hao Hu, Hua-Wei Zhou, and Robert R. Stewart10 June 2021 | GEOPHYSICS, Vol. 86, No. 4Delineating salt boundaries using 3D DAS-VSP acquired inside salt in the Gulf of MexicoY. Li, Y. Duan, T. Chen, and D. Johnson10 August 2019Reverse time migration of transmitted wavefields for salt boundary imagingChris Willacy and Maksym Kryvohuz12 February 2019 | GEOPHYSICS, Vol. 84, No. 2Imaging above an extended-reach horizontal well using converted shear waves and a rig sourceJakob B. U. Haldorsen, W. Scott Leaney, Richard T. Coates, Steen A. Petersen, Helge Ivar Rutledal, and Kjetil A. Festervoll4 February 2013 | GEOPHYSICS, Vol. 78, No. 2Salt flank imaging with side reflectionsZhiyong Jiang, Brian Hornby, and James Brewton8 August 2011 SEG Technical Program Expanded Abstracts 2009ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2009 Pages: 4338 publication data© 2009 Copyright © 2009 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished: 14 Oct 2009 CITATION INFORMATION Mark A. Roberts, Brian E. Hornby, and Francis Rollins, (2009), "3D salt‐flank imaging with transmitted arrival VSP data," SEG Technical Program Expanded Abstracts : 4129-4133. https://doi.org/10.1190/1.3255734 Plain-Language Summary PDF DownloadLoading ...
2112 Study on Disc Vibration in Critical Number of Rotations (2005)

DVD disc vibration at the critical number of rotations was examined to determine its cause and identify a means of reducing it. Disc vibration at the critical number of rotations is considered the vibration mode of a DVD disc, and the position of this vibration mode is always the same for a DVD drive. The relative inclination between the optical head and disc increases with the vibration. This paper describes the stabilization of the disc in a DVD recording system during high-speed rotation of the disc. The top cover of the drive is equipped with a disc vibration control structure that controls the (0,2)-(0,4) vibration modes of the disc at the critical number of rotations, thereby reducing the relative inclination between the optical head and disc significantly.
Modeling the Impact of Service Level Agreements During Service Engagement (2014)

One of the key promises of IT strategic outsourcing is to deliver greater IT service management through lower cost. However, this raises a critical question: How can one predict the service delivery cost that will deliver the promised service level agreements (SLAs)? This is particularly challenging since such prediction is mostly needed during the service engagement phase where the SLAs and the delivery cost are negotiated, and the detailed service modeling data are not available. In this paper, we propose a modeling framework that uses queueing-model-based approaches to estimate the impact of SLAs on the delivery cost. We further propose a set of approximation techniques to address the complexity of service delivery and an optimization model to predict the delivery cost subject to service-level constraints and service stability conditions. We demonstrate the applicability of the proposed methodology using data from a large IT service delivery environment.
A Novel Liquid Silazane Precursor to Silicon Nitride. (1982)

The reaction of dichlorosilane, H2SiCl2, with gaseous ammonia in dichloromethane or diethyl ether solution results in formation of a silazane oil containing silicon, hydrogen, and nitrogen in good yield. This ammonolysis product can be pyrolyzed in a nitrogen atmosphere (temperature to 1150 C) to give alpha-Si3N4 in about 70% yield. The ceramic product formed has a relatively porous, fine-grained microstructure with some cracks and blisters.
Image collapsing concentrators. Interim scientific report No. 2 (1980)

A cylindrical Fresnel-type lens has been designed and ray traced that focuses approximately to lines over a 60/sup 0/ elevation angle interval. Forty stepped prism facets are configured on the inside surface of the lens, and the lens outer surface can be well approximated by a smooth circular arc. Especially contoured cylindrical subreflectors are described for concentrating the broad image fields of the lens onto a narrow fixed shelf. These image collapsing subreflectors also compensate for focal shortening with azimuth angle incidence variations over nearly a +-60/sup 0/ sector. Ray tracing on the lens and subreflector provide approximate energy distributions on the absorber shelf over the large acceptance angle intervals. The expected performance characteristics of a solar concentrator using the curved lens with facets on the inside surface are compared with a concentrator employing a straight stepped prism lens with facets cut on the outer lens surface.
Integrating the markers Pan I and haemoglobin with the genetic linkage map of Atlantic cod (Gadus morhua) (2010)

The genetic linkage map presented here incorporates the marker Pan I, together with multiple Hb loci, and integrates genetic linkage data produced by two different research groups. This represents a useful resource to further explore if Pan I and Hbs or other genes underlie quantitative trait loci (QTL) for temperature sensitivity/tolerance or other phenotypes.
Wide-field whole eye OCT system with demonstration of quantitative retinal curvature estimation (2018)

Current conventional clinical OCT systems image either only the anterior or the posterior eye during a single acquisition. This localized imaging limits conventional OCT's use for characterizing global ocular morphometry and biometry, which requires knowledge of spatial relationships across the entire eye. We developed a "whole eye" optical coherence tomography system that simultaneously acquires volumes with a wide field-of-view for both the anterior chamber (14 x 14 mm) and retina (55°) using a single source and detector. This system was used to measure retinal curvature in a pilot population and compared against curvature of the same eyes measured with magnetic resonance imaging.
The essential and non-essential genes of Bovine herpesvirus 1 (2008)

Bovine herpesvirus 1 (BoHV-1) is an economically important pathogen of cattle associated with respiratory and reproductive disease. To further develop BoHV-1 as a vaccine vector, a study was conducted to identify the essential and non-essential genes required for in vitro viability. Random-insertion mutagenesis utilizing a Tn5 transposition system and targeted gene deletion were employed to construct gene disruption and gene deletion libraries, respectively, of an infectious clone of BoHV-1. Transposon insertion position and confirmation of gene deletion were determined by direct sequencing. The essential or non-essential requirement of either transposed or deleted open reading frames (ORFs) was assessed by transfection of respective BoHV-1 DNA into host cells. Of the 73 recognized ORFs encoded by the BoHV-1 genome, 33 were determined to be essential and 36 to be non-essential for virus viability in cell culture; determining the requirement of the two dual copy ORFs was inconclusive. The majority of ORFs were shown to conform to the in vitro requirements of BoHV-1 homologues encoded by human herpesvirus 1 (HHV-1). However, ORFs encoding glycoprotein K (UL53), regulatory, membrane, tegument and capsid proteins (UL54, UL49.5, UL49, UL35, UL20, UL16 and UL7) were shown to differ in requirement when compared to HHV-1-encoded homologues.
Synthesis of 1,6-Disubstituted 4,5,6,7-Tetrahydropyrazolo[3,4-c]pyridin-7-one Derivatives and Evaluation of Their Anticancer Activity (2012)

Promising anticancer compounds of the type 1,6-disubstituted 4,5,6,7-tetrahydropyrazolo[3,4-c]pyridin-7-ones were identified. The target compounds were readily synthesized in a large scale via a sequence of reactions starting from the commercially available primary amines. Their in vitro anti-proliferative activity has been evaluated on prostate (DU-145), colon (HT-29 and HCT-116) and melanoma (A375P) human cancer cell lines. The relationships between the structure and the anticancer activity, covering all tested cancer cell lines, revealed that the compound 5c with 2,4-dimethylphenyl substituent at <TEX>$R^2$</TEX> was the most potent with the <TEX>$IC_{50}$</TEX> values in the range as low as 0.16 to <TEX>$0.40{\mu}M$</TEX>.
Retinoic acid receptor gamma: specific immunodetection and phosphorylation. (1991)

Synthetic peptides corresponding to cDNA-deduced amino acid sequences unique to the human and mouse retinoic acid receptor gamma 1 (hRAR-gamma 1 and mRAR-gamma 1, respectively) were used to generate anti-RAR-gamma 1 antibodies. Four mAbs were selected, which were directed against peptides found in region A1 (Ab1 gamma (A1)), region F (Ab2 gamma (mF) and Ab4 gamma (hF)) and region D2 (Ab5 gamma (D2)). These antibodies specifically immunoprecipitated and recognized by Western blotting RAR-gamma 1 proteins in COS-1 cells transfected with expression vectors containing the RAR-gamma 1 cDNAs. They all reacted with both human and mouse RAR-gamma 1 proteins, except Ab4 gamma (hF) that was specific for hRAR-gamma 1. Rabbit polyclonal antibodies, directed against a peptide from the mRAR-gamma 1 F region were also obtained (RP gamma (mF)) and found to be specific for mouse RAR-gamma 1 protein. Furthermore, in gel retardation/shift assays the antibodies specifically retarded the migration of complexes obtained with a RA response element (RARE). Antibodies raised against regions D2 and F also recognized the RAR-gamma 2 isoform which differs from RAR-gamma 1 only in the A region. On the other hand, antibodies directed against the A1 region of RAR-gamma 1 (Ab1 gamma (A1)) only reacted with the RAR-gamma 1 protein. The antibodies characterized here allowed us to detect the presence of mRAR-gamma 1 and gamma 2 isoforms in mouse embryos and F9 embryonal carcinoma cells nuclear extracts. They were also used to demonstrate that the mRAR-gamma 1 protein can be phosphorylated and that the phosphorylation occurs mainly in the NH2-terminal A/B region.
High isolation, planar filters using EBG substrates (2001)

The concept of electromagnetic bandgaps (EBGs) has been utilized to develop a high-quality filter that can be integrated monolithically with other components due to a reduced height, planar design. Coupling adjacent defect elements in a periodic lattice creates a filter characterized by its ease of fabrication, high-Q performance, high-port isolation, and integrability to planar or 3-D circuit architectures. The filter proof of concept has been demonstrated in a metallo-dielectric lattice. The measured and simulated results of 2-, 3-, and 6-pole filters are presented at 10.7 GHz.
Electrorheological fluids: structures and mechanisms (2007)

Electrorheology denotes the control of a colloid's flow properties through an electric field. We delineate the basic characteristics of electrorheological (ER) fluids, and show that the use of an effective dielectric constant concept can yield quantitative predictions. In particular, the ground state structure, the structural transition that occurs under crossed electric and magnetic fields, the high-field yield stress and its variation with particle size are all in good agreement with the experiments. The recently discovered giant electrorheological effect, owing its origin to molecular dipoles, is described and contrasted with the conventional ER effect that arises from induced polarization effects.
Design and development of a self-contained personal electrostatic bioaerosol sampler (PEBS) with a wire-to-wire charger (2017)

Here, we present a concept of a personal electrostatic bioaerosol sampler (PEBS), which is an open channel collector consisting of a novel wire-to-wire particle charger and a collection section housing a double-sided and removable metal collection plate and two quarter-cylinder ground electrodes. The charger consists of a tungsten wire (25.4 mm long and 0.076 mm in diameter) connected to high voltage and positioned in the center of the charging section (a cylinder 50.8 mm long and 25.4 mm in diameter); a ring of stainless steel wire 0.381 mm in diameter surrounds the hot electrode at its midpoint and is grounded. The newly designed wire-to-wire charger produces lower ozone concentrations compared to traditional wire-to-plate or wire-to-cylinder charger designs. The particles captured on the collection plate are easily eluted using water or other fluids. The sampler was iteratively optimized for optimum charging and collection voltages, and collection electrode geometry. When tested with polystyrene latex particles ranging from 0.026 µm to 3.1 µm in diameter and 10 L/min collection flow rate, the sampler's collection efficiency was approximately 70%–80% at charging and collection voltages of +5.5 kV and −7 kV, respectively. The PEBS showed this collection efficiency at sampling times ranging from 10 min to 4 h. Preliminary tests with Bacillus atrophaeus bacterial cells and fungal spores of Penicillium chrysogenum showed similar collection efficiency. The use of a unique wire-to-wire charger resulted in ozone production below 10 ppb. Due to low ozone emissions, this sampler will allow maintaining desirable physiological characteristics of the collected bioaerosols, leading to a more accurate sample analysis.© 2017 American Association for Aerosol Research
An approach for reverse engineering of relational databases (1994)

he rationale for reengineering is straightforward: new software is
Human pluripotent stem cell-derived brain pericyte-like cells induce blood-brain barrier properties (2018)

ABSTRACT Brain pericytes play an important role in the formation and maintenance of the neurovascular unit (NVU), and their dysfunction has been implicated in central nervous system (CNS) disorders. While human pluripotent stem cells (hPSCs) have been used to model other components of the NVU including brain microvascular endothelial cells (BMECs), astrocytes, and neurons, cells having brain pericyte-like phenotypes have not been described. In this study, we generated neural crest stem cells (NCSCs), the embryonic precursor to forebrain pericytes, from human pluripotent stem cells (hPSCs) and subsequently differentiated NCSCs to brain pericyte-like cells. The brain pericyte-like cells expressed marker profiles that closely resembled primary human brain pericytes, and they self-assembled with endothelial cells to support vascular tube formation. Importantly, the brain pericyte-like cells induced blood-brain barrier (BBB) properties in BMECs, including barrier enhancement and reduction of transcytosis. Finally, brain pericyte-like cells were incorporated with iPSC-derived BMECs, astrocytes, and neurons to form an isogenic human NVU model that should prove useful for the study of the BBB in CNS health, disease, and therapy.