gebhart/patrepeval huggingface dataset:
Non-Axisymmetric Inflatable Pressure Structure (NAIPS) Full-Scale Pressure Test (2017)

Inflatable space structures have the potential to significantly reduce the required launch volume for large pressure vessels required for exploration applications including habitats, airlocks and tankage. In addition, mass savings can be achieved via the use of high specific strength softgoods materials, and the reduced design penalty from launching the structure in a densely packaged state. Large inclusions however, such as hatches, induce a high mass penalty at the interfaces with the softgoods and in the added rigid structure while reducing the packaging efficiency. A novel, Non-Axisymmetric Inflatable Pressure Structure (NAIPS) was designed and recently tested at NASA Langley Research Center to demonstrate an elongated inflatable architecture that could provide areas of low stress along a principal axis in the surface. These low stress zones will allow the integration of a flexible linear seal that substantially reduces the added mass and volume of a heritage rigid hatch structure. This paper describes the test of the first full-scale engineering demonstration unit (EDU) of the NAIPS geometry and a comparison of the results to finite element analysis.
An investigation into the applicability of the wavelet transform to digital stereo image matching (2002)

Stereo vision systems require the stereo images to be automatically matched. Multiresolution matching techniques have been applied to the matching problem. The wavelet transform, which produces a representation which is intermediate between a spatial and a frequency representation, can be viewed as a multiresolution decomposition technique. The lack of shift invariance of the wavelet transform restricts its applicability in stereo image matching. An hierarchical image matching technique is described which can use a Gaussian or a wavelet image pyramid. The results of using the two image pyramids are compared to evaluate the applicability of the wavelet transform. The results indicate that neither the wavelet pyramid or the Gaussian pyramid have an advantage over the other. However, it also indicates that the wavelet transform can be applied to digital stereo image matching.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The role of DNA hypermethylation in human neoplasia (2000)

Cancer development and progression is dictated by a series of alterations in genes such as oncogenes, tumor suppressor genes, DNA repair genes, and others. DNA methylation is an epigenetic modification that is profoundly altered in most cancers. Recently, hypermethylation of CpG-rich areas located in the promoter of genes (CpG islands) has been shown to be commonly implicated in silencing tumor suppressor genes in cancer. By cloning and characterizing a large number of such CpG islands hypermethylated in colon cancer, we found that two processes explain most of these events. Age-related CpG island methylation in a subset of cells in normal tissues, followed by intensification of methylation in cancer cells explains the majority of hypermethylation events in colon cancer and may provide a mechanistic link between aging and cancer formation. Most of the other CpG islands methylated in colon cancer can be explained by a newly described phenotype, the CpG island methylator phenotype (CIMP) which results in multiple methylation events in a subset of cancers. CIMP accounts for the majority of sporadic colon cancers characterized by microsatellite instability, as well as most tumors with k-ras mutations. Understanding further the factors that lead to, and modulate, aberrant methylation in cancer may provide novel avenues for prevention and treatment of this disease.
Improved Method for Numerical Solutions of the General Incompressible Fluid Film Lubrication Problem (1967)

A numerical analysis for determining performance characteristics of hydrodynamic, hydrostatic, or hybrid bearings with arbitrary clearance distribution is presented. Solution of the Reynolds lubrication equation for incompressible fluids is achieved by formation of coefficient matrices that act upon column vectors of the pressures progressively from one boundary to the other without requiring an iterative scheme. Multiple recesses are handled by component solutions. The external supply system is included and solved for an arbitrary type of individual recess compensation and supply circuit network. Sample results are indicated.
Turbine under Gulf Stream (TUGS) overview of an energy source potential (1994)

The authors present the details of a turbine under the Gulf Stream (TUGS) proposal submitted to the Advance Research Projects Agency (ARPA) under the Technology Reinvestment Project (TRP). The project is to design, build, and deploy the prototypes necessary to demonstrate the economic and technical feasibility of generating electric power from the Gulf Stream. The project is based in part on new generator designs and emerging materials technologies that significantly enhance the likelihood of success. Presented is the initial design, economic, and maintenance assumptions. The design, economic and maintenance assumptions are to be thoroughly tested, evaluated and refined during the course of the project. To be fully successful, the project shall demonstrate the technology and produce prototype turbines which can be mass produced and sold with service support to a wide variety of customers worldwide.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Regeneration of power in hybrid vehicles (2003)

Regeneration is one of the important sources of improving fuel efficiency. When designing the drive train of a hybrid vehicle, special attention must be given to this effect. We analyse the effect of regeneration of the braking energy on the design of the electrical motors and of the battery system. We consider a light urban vehicle and a bus to cover the whole spectrum of possible hybrid vehicles. Induction and permanent magnet synchronous traction motors are designed for both vehicles. We compare and analyse the consequences of their design on the regeneration. The battery behaviour is also considered with the various motors. It is shown that the choice of the motors has little effect on the recuperation and that effective recuperation can be obtained relatively easily if the motors and the braking system are adequately designed and matched. The conclusion is valid practically for all types of hybrid drive trains (series, parallel and series-parallel hybrids).
Perovskite seeding growth of formamidinium-lead-iodide-based perovskites for efficient and stable solar cells (2018)

Formamidinium-lead-iodide (FAPbI<sub>3</sub>)-based perovskites with bandgap below 1.55 eV are of interest for photovoltaics in view of their close-to-ideal bandgap. Record-performance FAPbI<sub>3</sub>-based solar cells have relied on fabrication via the sequential-deposition method; however, these devices exhibit unstable output under illumination due to the difficulty of incorporating cesium cations (stabilizer) in sequentially deposited films. Here we devise a perovskite seeding method that efficiently incorporates cesium and beneficially modulates perovskite crystallization. First, perovskite seed crystals are embedded in the PbI<sub>2</sub> film. The perovskite seeds serve as cesium sources and act as nuclei to facilitate crystallization during the formation of perovskite. Perovskite films with perovskite seeding growth exhibit a lowered trap density, and the resulting planar solar cells achieve stabilized efficiency of 21.5% with a high open-circuit voltage of 1.13 V and a fill factor that exceeds 80%. The Cs-containing FAPbI<sub>3</sub>-based devices show a striking improvement in operational stability and retain 60% of their initial efficiency after 140 h operation under one sun illumination.
An adaptive autonomous network congestion controller (2002)

This paper introduces a network congestion controller that operates autonomously and asynchronously on the basis of very basic measurements available at the sources. Convergence of the algorithm for a fixed offered load under reasonable assumptions is proven.
A 79-GHz Adaptive-Gain and Low-Noise UWB Radar Receiver Front-End in 65-nm CMOS (2016)

A 79-GHz adaptive-gain and low-noise ultra-wideband radar receiver RF front-end integrated circuit in 65-nm CMOS is presented in this paper. The receiver consists of an adaptive-gain low-noise amplifier (AGLNA) and a g m-boosted sub-harmonic mixer (SHM). The proposed AGLNA controls the gain with adaptive biased circuits, which lowers the gain as the received signal power increases to provide wide dynamic range to the radar receiver without any external controls. We analyzed the input impedance of a cascode amplifier with a parallel resonant inductor, which improves the noise figure. The proposed g m-boosted SHM uses a transformer-based feedback network with NMOS bleeding circuits to provide a high conversion gain. The SHM was designed to use a differential local oscillator (LO) signal to have a simple structure and operate at low LO power. The measured conversion gain range was from 16 to -7.5 dB with a received power range from -45 to -5 dBm at 79.5 GHz. The measured noise figure was 10.5 dB and the measured 2LO-to-RF isolation was 70 dB. The chip area is 0.47×1.23 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .
Free Magnetic Induction in Nuclear Quadrupole Resonance (1955)

The free precession of an ensemble of nuclear quadrupole moments in an axial electric field gradient is studied by the pulsed nuclear induction method. A quantum-mechanical analysis describes the free precession and spin echo signals which result from the application of single and double pulses of radio-frequency field at the condition of zero-field quadrupole resonance. Beat modulation effects exhibited by free precession signals in a small constant external magnetic field are predicted by analysis. An alternative semiclassical description of quadrupole precession is given, which is analogous to the macroscopic nuclear induction equations of Bloch. Theory is verified by observation of free precession signals of chlorine in NaCl${\mathrm{O}}_{3}$.
The Characterization of Biologically Available Strontium Isotope Ratios for the Study of Prehistoric Migration (2002)

Strontium isotope analysis of bone and tooth enamel from prehistoric human skeletons is an important new technique used to address questions regarding migration. Two problems arise in such investigations: (1) levels of strontium isotope ratios in local bedrock, soil, water, plants and animals are variable; and (2) a range of values in human bone and enamel data make it difficult to distinguish some migrants from locals. Analysis of the bones of small animals provides a robust measure of local strontium isotope ratios and a reliable, if conservative, means for determining confidence limits for distinguishing migrants. Data from various geographical areas are presented here in a discussion of variability in strontium isotope values. Examples are provided using modern and prehistoric materials. We conclude with the recommendation that studies involving strontium isotope analysis should incorporate small animal samples for comparative purposes whenever possible.
Plant responses to sulphur deficiency and the genetic manipulation of sulphate transporters to improve S‐utilization efficiency (2000)

Decreased inputs of S have increased the incidence of S-deficiency in crops, resulting in decreased yields and quality. Remediation by fertilizer application is not always successful because this often results in an uneven supply of S. The ability to respond to S-deficiency stress varies between crops and this is a target for the genetic improvement of S-utilization efficiency. Improved capture of resources, the accumulation of greater reserves of S and improved mechanisms for the remobilization of these reserves are required. It is an inability to over-accumulate S and subsequently, effectively remobilize S-reserves, which restricts optimum S-use efficiency. Genetic manipulation of the transporters and their expression will contribute to overcoming these limitations. Control of gene expression limits excess uptake and activity of the assimilatory pathway: the endogenous expression of sulphate transporters is regulated by S-supply, with negative regulation from reduced S-containing compounds and positive regulation by O-acetylserine, the C/N skeleton precursor of cysteine. Constitutive expression of the transporter will remove this control and may enable the accumulation of sulphate reserves. Sulphate in the vacuole and other pools of reduced sulphur, such as glutathione or protein may be remobilized under S-limiting conditions. Low efficiencies of these remobilization processes, particularly the remobilization of vacuolar sulphate, suggest that the transporters involved in the remobilization are a target for modification. Transporters are involved in facilitating the multiple trans-membrane transport steps between uptake of sulphate from the soil solution, and delivery to the site of reduction in the chloroplast or plastid. A gene family has been identified and phylogenetic relationships based on primary sequence information indicate multiple sub-groups. Groups which are expressed in roots, in shoots and in both tissue types are postulated, however, the functional roles for these groups and the identification of transporters involved in recycling remain to be confirmed.
The Ov20 Protein of the Parasitic Nematode Onchocerca volvulus (1997)

Ov20 is a major antigen of the parasitic nematode Onchocerca volvulus, the causative agent of river blindness in humans, and the protein is secreted into the tissue occupied by the parasite. DNA encoding Ov20 was isolated, and the protein was expressed in Escherichia coli. Fluorescence-based ligand binding assays show that the protein contains a high affinity binding site for retinol, fluorescent fatty acids (11-((5-dimethylaminonaphthalene-1-sulfonyl)amino)undecanoic acid, dansyl-DL-alpha-aminocaprylic acid, and parinaric acid) and, by competition, oleic and arachidonic acids, but not cholesterol. The fluorescence emission of dansylated fatty acids is significantly blue-shifted upon binding in comparison to similarly sized beta-sheet-rich mammalian retinol- and fatty acid-binding proteins. Secondary structure prediction algorithms indicate that a alpha-helix predominates in Ov20, possibly in a coiled coil motif, with no evidence of beta structures, and this was confirmed by circular dichroism. The protein is highly stable in solution, requiring temperatures in excess of 90 degrees C or high denaturant concentrations for unfolding. Ov20 therefore represents a novel class of small retinol-binding protein, which appears to be confined to nematodes. The retinol binding activity of Ov20 could possibly contribute to the eye defects associated with onchocerciasis and, because there is no counterpart in mammals, represents a strategic target for chemotherapy.
Removal of the effect of Compton scattering in 3-D whole body positron emission tomography by Monte Carlo (2002)

A Monte Carlo technique has been developed to simulate and correct for the effect of Compton scatter in 3-D acquired PET whole body imaging. The method utilizes the attenuation corrected and normalized, 3-D reconstructed image volume as the source intensity distribution for a photon-tracking Monte Carlo simulation. It is assumed that the number of events in each pixel of the image represents the isotope concentration at that location in the body. The history of each annihilation photon's interactions in the scattering media is followed. The edges and average attenuation coefficients of the various scattering media are determined using a segmented image volume derived from a short transmission scan. The sinograms for the scattered and unscattered photon pairs are generated in a simulated 3-D PET acquisition. The calculated scatter contribution is used to correct the original data set. The method is general and can be applied to any scanner configuration or geometry. In its current form the simulation requires 20 hours on a Sparc10 when every pixel in a 89-plane, 128/spl times/128 pixel, 3-D acquired (CTI 961, two bed positions) image volume is sampled, and roughly 1 hour when 16 pixels (4/spl times/4) are grouped as a single pixel. Here, the authors present results of the scatter correction method using a 3-D acquired human study of the thorax as input.
Performance and Reporting of Clinical Breast Examination: A Review of the Literature (2004)

Clinical breast examination (CBE) seeks to detect breast abnormalities or evaluate patient reports of symptoms to find palpable breast cancers at an earlier stage of progression, when treatment is more effective and treatment options are greater than for later stage disease. Evidence suggests that, for some women, CBE can be an important complement to mammography in the earlier detection of breast cancer; CBE identifies some cancers missed by mammography and provides an important screening tool among women for whom mammography is not recommended or women who do not receive high-quality screening mammography according to recommended guidelines. But CBE performance and reporting approaches are inconsistent. Health care providers indicate that they are not confident in their CBE skills and would welcome training. Studies demonstrate that training can enhance CBE performance, measured in terms of execution of CBE components and accuracy. This literature review provides evidence to the extent that it is available, to support the specific recommendations of Saslow, et al. for optimizing CBE performance and reporting and to guide further research on CBE performance characteristics, reporting systems, barriers to high-quality CBE performance, and training.
Polymerase chain reaction detection of 8 putative periodontal pathogens in subgingival plaque of gingivitis and advanced periodontitis lesions (1996)

A 16S rRNA-based polymerase chain reaction (PCR) detection method was used to determine the prevalence of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia. Prevotella nigrescens and Treponema denticola in subgingival specimens of 50 advanced periodontitis, 50 adult gingivitis and 50 pediatric gingivitis subjects. The optimal PCR conditions were determined for each study species. Agarose gel electrophoresis of PCR products from each study species revealed a single band of the predicted size. Restriction enzyme digestion of amplicons confirmed the specificity of the amplification. PCR detection limits were in the range of 25-100 cells. No cross-reactivity with other oral micro-organisms or nonspecific amplification was observed. The prevalence by PCR in advanced periodontitis, adult gingivitis and pediatric gingivitis subjects was 30%, 14% and 14% for A. actinomycetemcomitans, 86%, 18% and 8% for B. forsythus, 74%, 52% and 78% for C. rectus, 80%, 70% and 66% for E. corrodens, 70%, 10% and 14% for P. gingivalis, 58%, 12% and 18% for P. intermedia, 52%, 20% and 22% for P. nigrescens, and 54%, 16% and 16% for T. denticola, respectively. The prevalence was higher in the advanced periodontitis group than in both adult gingivitis and pediatric gingivitis for A. actinomycetemcomitans, B. forsythus, P. gingivalis, P. intermedia, P. nigrescens and T. denticola at P < 0.01, and for E. corrodens at P < 0.05. The prevalence of C. rectus was significantly higher in the advanced periodontitis group than in the adult gingivitis group at P < 0.01. Matching results between PCR and culture occurred in 28% (B. forsythus) to 71% (A. actinomycetemcomitans) of the samples; the major discrepancy occurred in the PCR-positive/culture-negative category. Matching results between PCR and DNA probe methods were found in 84% of the subjects (B. forsythus) and 70% (P. gingivalis). Odds ratio analysis revealed statistically significant positive associations between 17 of the 28 possible combinations (P < 0.01). This study demonstrated the utility of a 16S rRNA-based PCR detection method for identifying important subgingival microorganisms. The results indicated a strong association between the study species and periodontitis. Several previously unreported symbiotic relationships were found between the 8 species tested.
Numerical Simulation of Turbulent Flames based on a Hybrid RANS/Transported-PDF Method and REDIM Method (2018)

A hybrid RANS/Transported-PDF model for the simulation of turbulent reacting flows based on automatically reduced mechanisms for the chemical kinetics (reaction-diffusion manifold, REDIM) is presented in this work. For modelling of turbulent reacting flows, chemistry is a key problem and affects largely the accuracy. The PDF method has been widely used since the chemical source term is in a closed form, without any modelling. Despite of this advantage of PDF method, detailed chemical kinetics is not desired due to its heavy computational effort. From this aspect, the detailed chemical kinetics is simplified by the reaction-diffusion manifold (REDIM) method. The hybrid RANS/Transported-PDF model based on REDIM reduced kinetics is applied to simulate the Sandia piloted Flame E, which has a moderate degree of local extinction. The numerical results are validated through comparison with experimental data and show good qualitative and quantitative agreements.
Multiuser Water-filling in the Presence of Crosstalk (2007)

Spectrum optimization is an important part of the design of interference-limited multiuser communication systems. While traditional water-filling provides a closed-form solution to the transmit optimization problem in a single-user system, the multiuser version of the problem often leads to nonconvex problem formulations which are difficult to solve. Motivated by high-speed parallel-link and digital subscriber line applications, this paper investigates two practical multiuser settings in which global or local optimal solutions to the multiuser spectrum optimization problems can be found efficiently. The first part of this paper considers a high-speed transmission system in which practical (but suboptimal) minimum-mean-squared-error linear equalizers (MMSE-LEs) are used at the receiver. The optimal single-user transmit spectrum in this case involves a modified water-filling solution. Surprisingly, such a modified water-filling spectrum can be shown to be near-optimal in a multiuser setting as well, if the direct-link and the crosstalk characteristics are symmetric and if crosstalk is reasonably small. Thus, for practical parallel-link systems using MMSE linear equalizers, the optimal single-user and multiuser spectra are nearly identical. The second part of this paper considers numerical techniques for solving a nonconvex multiuser rate maximization problem for digital subscriber line applications. A new ingredient in the proposed approach is a taxation scheme that takes into account the effect of interference between neighboring lines. This leads to a modified iterative water-filling algorithm which is capable of finding local optimum solutions to the multiuser spectrum optimization problem efficiently.