gebhart/patrepeval huggingface dataset:
Robust detection of atrial fibrillation for a long term telemonitoring system (2005)

We present a method to automatically detect atrial fibrillation (AF) for ambulatory monitoring with arbitrary lead placements. We aim for robust AF detection in the face of significant muscle artifact and potentially changing morphology. Our approach is based on the variance of R-R intervals since the QRS spike is the most prominent feature of an ambulatory ECG and the least confounded by muscle noise. Specifically, we use the morphology-independent QRS detector wqrs to compute R-R intervals and variance and then smooth the resulting classifications for further robustness. Experiments on the MIT-BIH AF database (AFDB) show our AF detection algorithm has sensitivity 0.96 with specificity 0.89 which is sufficient for AF screening
High Power Demonstration of a 100 kW Nested Hall Thruster System (2019)

The XR-100 team successfully completed high power system testing of a Nested Hall Thruster system made up of the X3 Nested Hall Thruster, a modular Power Processing Unit, and a 5 valve Mass Flow Controller as the culmination of work performed under a NASA NextSTEP program. The test campaign attained several key firsts, including highest directly measured thrust of an electric propulsion (EP) string, highest demonstrated current of an EP string, and highest power operation of an EP string at thermal equilibrium published to date. Most importantly, the XR-100 system testing demonstrated that a 100 kW-class Nested Hall Thruster system has comparable performance and behavior to current state-of-the-art mid power Hall Thrusters, validating that the heritage technology can be scaled up to 100+ kW
Abstract 2558: VEGF-dependent suppression of prostaglandin transporter (PGT) expression in Kras mutant human bronchial epithelial cells (2012)

Abstract Prostaglandin transporters are expressed in cyclooxygenase-positive cells and provide the dominant mechanisms for transport of prostaglandins (PG) across the cell membrane. Specifically, the prostaglandin transporter PGT, expressed in many cell types including lung epithelia, is responsible for the uptake of prostaglandin E2 (PGE2) for intracellular metabolism and degradation by 15-prostaglandin dehydrogenase (15-PGDH). The regulation of prostaglandin transporters has not been fully explored in lung cancer. We hypothesize that loss of PGT expression is important in lung carcinogenesis and its loss may be enhanced in the presence of common mutations in premalignant bronchial epithelial cells and non-small cell lung cancer (NSCLC). Our preliminary studies show that PGT expression (protein and mRNA) and 15-PGDH are significantly downregulated in Kras mutant human bronchial epithelial cells (HBEC) and in NSCLC. It is well known that Kras mutant cancers are associated with increased production of VEGF, an important factor in tumor angiogenesis. In HBEC, we found significantly higher VEGF levels in Kras mutants compared to vector controls (2242 versus 628 pg/mg, p = 0.04). We proposed that VEGF modulates PGT expression and tested our hypothesis by treating HBEC and NSCLC with human recombinant VEGF. PGT expression is downregulated with exogenous VEGF treatment and neutralizing VEGF production (neutralizing VEGF antibody) prevented the loss of PGT expression. The MEK1/2 inhibitor PD98059 upregulated PGT expression in HBEC Kras. Our results suggest Kras mutation is associated with loss of PGT expression and may be dependent on VEGF production. Modulation of PGT expression may be important in lung carcinogenesis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2558. doi:1538-7445.AM2012-2558
Use of a multigrid technique to study effects of limited sampling of heterogeneity on transport prediction (1987)

Reliable ground water transport prediction requires accurate spatial and temporal characterization of a hydrogeologic system. However, cost constraints and the desire to maintain site integrity by minimizing drilling can restrict the amount of spatial sampling that can be obtained to resolve the flow parameter variability associated with heterogeneities. This study quantifies the errors in subsurface transport predictions resulting from incomplete characterization of hydraulic conductivity heterogeneity. A multigrid technique was used to simulate two-dimensional flow velocity fields with high resolution. To obtain these velocity fields, the finite difference code MGRID, which implements a multigrid solution technique, was applied to compute stream functions on a 256-by-256 grid for a variety of hypothetical systems having detailed distributions of hydraulic conductivity. Spatial variability in hydraulic conductivity distributions was characterized by the components in the spectrum of spatial frequencies. A low-pass spatial filtering technique was applied to the base case hydraulic conductivity distribution to produce a data set with lower spatial frequency content. Arrival time curves were then calculated for filtered hydraulic conductivity distribution and compared to base case results to judge the relative importance of the higher spatial frequency components. Results indicate a progression from multimode to single-mode arrival time curves as the numbermore » and extent of distinct flow pathways are reduced by low-pass filtering. This relationship between transport predictions and spatial frequencies was used to judge the consequences of sampling the hydraulic conductivity with reduced spatial resolution. 22 refs., 17 figs.« less
Copper‐Mediated CC Cross‐Coupling Reaction of Monocarba‐closo‐dodecaborate Anion for the Synthesis of Functional Molecules (2013)

Kreuzkupplungen am Kohlenstoff-Eckzentrum eines Monocarba-closo-dodecaborats ermöglichen die effiziente Einführung verschiedener Arylgruppen und anderer über sp2/sp-hybridisierte Kohlenstoffzentren gebundener Substituenten. Ein Kupfer(I)-Komplex erleichtert die Umsetzung mit zahlreichen Elektrophilen bei Raumtemperatur. Die Reaktion lieferte eine Reihe C-arylierter Carboran-Anionen (siehe Bild; B grün, C blau), darunter auch an Androgen-Rezeptoren bindende Substanzen und solche mit mesogenen Eigenschaften. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
1H and 19F NMR chemical shifts for hydrogen bond strength determination: Correlations between experimental and computed values (2022)

1H and 19F NMR methods based on chemical shift measurements of different hydrogen bond donors used for quantifying hydrogen bond strength were analyzed and compared. The extracted values from these different methods are shown to be highly correlated with each other and with several experimental and ab initio computed quantities characterizing hydrogen bond formation. The titration method based on 19F NMR spectroscopy was performed for detecting and quantifying the formation of very weak hydrogen bond complexes such as those involving fluorine atoms as hydrogen bond acceptors. This approach represents a powerful and reliable method for studying and characterizing these complexes that, although weak, are very relevant.
Optical waveguides having flattened high order modes (2023)

A deterministic methodology is provided for designing optical fibers that support field-flattened, ring-like higher order modes. The effective and group indices of its modes can be tuned by adjusting the widths of the guide's field-flattened layers or the average index of certain groups of layers. The approach outlined here provides a path to designing fibers that simultaneously have large mode areas and large separations between the propagation constants of its modes.
Automatic Curriculum Design for Object Transportation Based on Deep Reinforcement Learning (2021)

This paper presents an automatic curriculum learning (ACL) method for object transportation based on deep reinforcement learning (DRL). Previous studies on object transportation using DRL have a sparse reward problem that an agent receives a rare reward for only the transportation completion of an object. Generally, curriculum learning (CL) has been used to solve the sparse reward problem. However, the conventional CL methods should be manually designed by users, which is difficult and tedious work. Moreover, there were no standard CL methods for object transportation. Therefore, we propose an ACL method for object transportation in which human intervention is unnecessary at the training step. A robot automatically designs curricula itself and iteratively trains according to the curricula. First, we define the difficult level of object transportation using a map, which is determined by the predicted travelling distance of an object and the existence of obstacles and walls. In the beginning, a robot learns the object transportation at an easy level (i.e., travelling distance is short and there are less obstacles around), then learns a difficult task (i.e., the long travelling distance of an object is required and there are many obstacles around). Second, training time also affects the performance of object transportation, and thus, we suggest an adaptive determining method of the number of training episodes. The number of episodes for training is adaptively determined based on the current success rate of object transportation. We verified the proposed method in simulation environments, and the success rate of the proposed method was 14% higher than no-curriculum. Also, the proposed method showed 63% (maximum) and 14% (minimum) higher success rates compared with the manual curriculum methods. Additionally, we conducted real experiments to verify the gap between simulation and practical results.
Novel Technology for Bio-diesel Production from Cooking and Waste Cooking Oil by Microwave Irradiation (2015)

In the transitional process, acid or base catalysts are common technology to produce bio-diesel from waste cooking oil; however, the catalysts only can be use one time. Highly reaction time is requirement for the transitional technology. For improvement these concern issues, this study applied a novel technology to create bio-diesel product from cooking oil and waste cooking oil by microwave irritation. The microwave irradiation can provide strong power and reach reaction temperature in a short time. The SrO catalyst is a heterogeneous catalyst which is not dissolution into any liquid solution therefore, it can be recycling and reusing again. In this research, the optimum conditions were using commercial SrO, 40 to 180 seconds reaction time, around 80oC reaction temperature, 6 methanol to oil ratio, and 1000W microwave power output. 99% and 93% biodiesel conversion efficiency for cooking oil and waste cooking oil were reached within in these conditions. The determined specifications of obtained biodiesel according to ASTM D6751 and EN14214 standards were in accordance with the required limits. As a conclusion, the present study indicates that derived fuel promises being an alternative for diesel, and could be used in engines without a major modification due to its qualifications.
On the Double-Inflection Characteristic of the Continuous-Wave AM/AM in Class-F−1 Power Amplifiers (2018)

This letter investigates the impact of open second-harmonic impedance on the static amplitude-to-amplitude modulation (AM/AM) characteristic of class-F <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> power amplifiers (PAs). The phenomenon of double gain compression in harmonically tuned PAs is analyzed for the first time. The study starts with presenting a theoretical postulation explaining the occurrence of inflection points in AM/AM profiles of class-F <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> PAs. Thereafter, a simplified mathematical model providing closed-form expressions for predicting the locations of output power levels of the first and second AM/AM inflection points is presented. For practical validation, an active load-pull system is used to synthesize class-F <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> load conditions using a 0.7-mm NXP GaN die at a frequency of 2.6 GHz. The gain curve profile varies quite significantly as a function of second harmonic load reactance and it has been measured to capture the AM/AM inflection phenomenon at low power levels. Under class-F <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> harmonic loading conditions at 28 and 48 V, the active load-pull measurements demonstrate the phenomenon of AM/AM inflection and agree well with the mathematical analysis presented in this letter.
Structure-Based Design of β-Lactamase Inhibitors. 1. Synthesis and Evaluation of Bridged Monobactams (1998)

Bridged monobactams are novel, potent, mechanism-based inhibitors of class C beta-lactamases, designed using X-ray crystal structures of the enzymes. They stabilize the acyl-enzyme intermediate by blocking access of water to the enzyme-inhibitor ester bond. Bridged monobactams are selective class C beta-lactamase inhibitors, with half-inhibition constants as low as 10 nM, and are less effective against class A and class B enzymes (half-inhibition constants > 100 microM) because of the different hydrolysis mechanisms in these classes of beta-lactamases. The stability of the acyl-enzyme complexes formed with class C beta-lactamases (half-lives up to 2 days were observed) enabled determination of their crystal structures. The conformation of the inhibitor moiety was close to that predicted by molecular modeling, confirming a simple reaction mechanism, unlike those of known beta-lactamase inhibitors such as clavulanic acid and penam sulfones, which involve secondary rearrangements. Synergy between the bridged monobactams and beta-lactamase-labile antibiotics could be observed when such combinations were tested against strains of Enterobacteriaceae that produce large amounts of class C beta-lactamases. The minimal inhibitory concentration of the antibiotic of more than 64 mg/L could be decreased to 0.25 mg/L in a 1:4 combination with the inhibitor.
Enhanced mass resolution in a quadrupole ion trap (1993)

Abstract The versatility of the quadrupole ion trap as a mass spectrometer in which the mass resolution may be varied over a wide range has been demonstrated. Mass resolution of 0.8 × 10 7 and 1.2 × 10 7 have been obtained for ions of m / z 414 and m / z 614, respectively, well in excess of the normal value of 3 m , where m is the mass of ion. At the highest mass resolution, peak‐widths at half‐maximum are but 52 × 10 −6 u. While it has been shown previously that enhanced mass reslution in the quadrupole ion trap can be achieved by reduction of the mass scanning rate, the range of mass resolutions reported here were achieved by reducing the mass scanning rate, in stages, by an overall factor of ca 5.5 × 10 4 .
Phosphorescent Ir(iii) complexes with both cyclometalate chromophores and phosphine-silanolate ancillary: concurrent conversion of organosilane to silanolate (2013)

Ir(III) metal complexes with general formula [(C^N)2Ir(P^SiO)], where (C^N)H is 2-phenylisoquinoline (1), 2-phenylpyridine (2) or 2-(2,4-difluorophenyl)pyridine (3), and (P^SiO)H is an organosilanolate ancillary chelate with either diphenylsilyl (a) or dimethylsilyl (b) substituent, were synthesized, among which the structure of 3a was also confirmed using single-crystal X-ray diffraction analyses. These complexes exhibit bright phosphorescence in the region of 489-632 nm in solution at room temperature, showing the first successful example of using organosilanolate as an ancillary chelate. For application, organic light emitting diodes (OLEDs) using phosphors 3a and 3b doped in N,N'-dicarbazolyl-3,5-benzene (mCP) exhibited a maximum brightness of 50,800 cd m(-2) at 800 mA cm(-2) (12 V) with η(ext) of 10.1% and a brightness of 45,900 cd m(-2) at 700 mA cm(-2) (14.5 V) with η(ext) of 10.2%, respectively.
Abstract B65: High levels of expression of P-glycoprotein/multidrug resistance protein result in resistance to vintafolide (2015)

Abstract Targeting surface receptors overexpressed on cancer cells is one way to specifically treat cancer versus normal cells. Vintafolide (EC145), which consists of folate linked to a cytotoxic small molecule, desacetylvinblastine hydrazide (DAVLBH), takes advantage of the overexpression of folate receptor (FR) on cancer cells. Once bound to FR, vintafolide enters the cell by endocytosis, and the reducing environment of the endosome cleaves the linker, releasing DAVLBH to destabilize microtubules. Vintafolide has shown efficacy and improved tolerability compared to DAVLBH in FR-positive preclinical models. As the first FR-targeting drug to reach the clinic, vintafolide has achieved favorable responses in Phase II clinical trials in FR-positive ovarian and lung cancer. However, some FR-positive patients in these clinical trials do not respond to vintafolide. We sought to identify potential biomarkers of resistance to aid in the future development of this and other FR-targeting drugs. Here, we confirm in both in vitro and in vivo preclinical models that high P-glycoprotein (P-gp) expression was the strongest predictor of resistance to DAVLBH in a panel of 359 cancer cell lines. Furthermore, targeted delivery of DAVLBH via the FR as in vintafolide fails to overcome P-gp mediated efflux of DAVLBH as seen in FR-expressing engineered cell lines and in vivo models. Therefore, we suggest that patients whose tumors express high levels of P-gp be excluded from future clinical trials for vintafolide as well as other FR-targeted therapeutics bearing a P-gp substrate. Citation Format: Amy D. Guertin, Jennifer O'Neil, Alexander Stoeck, Joseph A. Reddy, Razvan Cristescu, Brian B. Haines, Marlene C. Hinton, Ryan Dorton, Alicia Bloomfield, Melissa Nelson, Marilynn Vetzel, Serguei Lejnine, Michael Nebozhyn, Theresa Zhang, Andrey Loboda, Kristen L. Picard, Emmett V. Schmidt, Isabelle Dussault, Christopher P. Leamon. High levels of expression of P-glycoprotein/multidrug resistance protein result in resistance to vintafolide. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B65.
Tracking performance of least-squares algorithms in time-varying ocean channels (2000)

Adaptive least-squares algorithms are widely used to estimate the state of or compensate for the effects of time-varying acoustic channels in the ocean environment. A special case of such time-varying channels is those through which the signals emitted by moving sources propagate. Current methods of characterizing the tracking behavior of these adaptive algorithms are limited to cases where the algorithm accurately models the time-varying behavior of the channel or for which this behavior has a particularly simple form. A new technique is presented which allows the performance of adaptive least-squares algorithms to be characterized for more general classes of channel fluctuations. The technique shows that the performance can be interpreted in terms of model mismatch. New applications enabled by the technique are presented. [Work supported by ONR.]
Breast Cancer Tissue Sub-Region Classification from Second Harmonic Generation Imagery via Machine Learning (2021)

Cancer treatment involves complex decision-making processes. A better understanding of recurrence risk at diagnosis, as well as prediction of treatment response (e.g., to choose the most cost-effective treatment path in an informed manner) are needed to produce the best possible outcomes at the patient level. Prior work shows that the forward/backward (F/B) ratio calculated from Second Harmonic Generation (SHG) imagery can be indicative of risk of recurrence if relevant tissue sub-regions are selected. The choice of which sub-regions to image is currently made by human experts, which is subjective and labor intensive. In this paper, we investigate machine learning methods to automatically identify tissue sub-regions that are most relevant to the prediction of breast cancer recurrence. We formulate the task as a multi-class classification problem and use support vector machine (SVM) classifiers as the inference engine. Given the limited amount of data available, we focus on exploring the feature extraction stage. To that end, we evaluate methods leveraging handcrafted features, deep features extracted from pre-trained models, as well as features extracted via transfer learning. The results show a steady trend of improvement on the classification accuracy as the features become more data-driven and customized to the task at hand. This is an indication that having larger amounts of labeled data could be beneficial for improving automated methods of classification. The best results achieved, using features learned via transfer learning from ResNet-101, correspond to 85% accuracy in a 3-class problem and 94% accuracy in a binary classification problem.
Effect of Autoclave Cure Temperature, Pressure, and Time on the Glass Transition Temperature and the Degree of Cure of Epoxy Film Adhesive Joints (2022)

Abstract This study investigates the effect of autoclave curing variables on the glass transition temperature of and the degree of cure and strength of epoxy film adhesive single lap joints (SLJs) under static tensile shear loading. Studied autoclave variables include the cure temperature, cure pressure, temperature, and pressure ramp rates on the glass transition temperature as well as the cure time duration. Test joints are made of Aluminum substrates that are autoclave-bonded using epoxy film adhesive (AF163-2k). For each variable combination of the autoclave process, the corresponding glass transition temperature of cured Epoxy film adhesive is obtained using Dynamic Mechanical Analysis (DMA-Q800). Test data are generated for both baseline joints [uncycled] as well as for joints that have been heat-cycled in an environmental chamber after initial autoclave bonding. Results show a strong correlation between the autoclave process variable combinations and the corresponding glass transition temperature bond strength, and the failure mode of test joints.