gebhart/patrepeval huggingface dataset:
Generation of a functional and durable vascular niche by the adenoviral <i>E4ORF1</i> gene (2008)

Vascular cells contribute to organogenesis and tumorigenesis by producing unknown factors. Primary endothelial cells (PECs) provide an instructive platform for identifying factors that support stem cell and tumor homeostasis. However, long-term maintenance of PECs requires stimulation with cytokines and serum, resulting in loss of their angiogenic properties. To circumvent this hurdle, we have discovered that the adenoviral E4ORF1 gene product maintains long-term survival and facilitates organ-specific purification of PECs, while preserving their vascular repertoire for months, in serum/cytokine-free cultures. Lentiviral introduction of E4ORF1 into human PECs (E4ORF1(+) ECs) increased the long-term survival of these cells in serum/cytokine-free conditions, while preserving their in vivo angiogenic potential for tubulogenesis and sprouting. Although E4ORF1, in the absence of mitogenic signals, does not induce proliferation of ECs, stimulation with VEGF-A and/or FGF-2 induced expansion of E4ORF1(+) ECs in a contact-inhibited manner. Indeed, VEGF-A-induced phospho MAPK activation of E4ORF1(+) ECs is comparable with that of naive PECs, suggesting that the VEGF receptors remain functional upon E4ORF1 introduction. E4ORF1(+) ECs inoculated in implanted Matrigel plugs formed functional, patent, humanized microvessels that connected to the murine circulation. E4ORF1(+) ECs also incorporated into neo-vessels of human tumor xenotransplants and supported serum/cytokine-free expansion of leukemic and embryonal carcinoma cells. E4ORF1 augments survival of PECs in part by maintaining FGF-2/FGF-R1 signaling and through tonic Ser-473 phosphorylation of Akt, thereby activating the mTOR and NF-kappaB pathways. Therefore, E4ORF1(+) ECs establish an Akt-dependent durable vascular niche not only for expanding stem and tumor cells but also for interrogating the roles of vascular cells in regulating organ-specific vascularization and tumor neo-angiogenesis.
A unified framework for semantics and feature based relevance feedback in image retrieval systems (2000)

The relevance feedback approach to image retrieval is a powerful technique and has been an active research direction for the past few years. Various ad hoc parameter estimation techniques have been proposed for relevance feedback. In addition, methods that perform optimization on multi-level image content model have been formulated. However, these methods only perform relevance feedback on the low-level image features and fail to address the images' semantic content. In this paper, we propose a relevance feedback technique, iFind, to take advantage of the semantic contents of the images in addition to the low-level features. By forming a semantic network on top of the keyword association on the images, we are able to accurately deduce and utilize the images' semantic contents for retrieval purposes. The accuracy and effectiveness of our method is demonstrated with experimental results on real-world image collections.
A photonic beamformer for a transmitting phased array antenna using WDM and a programmable photonic processor (2023)

This work presents a novel transmitting-side photonic beamformer (PBF) based on our previously presented microwave photonic signal processor. This new transmitting-side PBF architecture takes advantage of well-established optical techniques, like wavelength-division multiplexing, coherent detection, and programmable optical filtering. A full analytical description of the system is derived, and an experimental demonstration is showcased. Results demonstrate the beam-steering capabilities of the proposed beamformer. The applicability of this transmitting-side PBF in the context of satellite communications is discussed.
Algebraic filters for filtered backprojection (2017)

<p>\n\tComputed Tomography (CT) is an imaging technique that is used to calculate the interior of an object using X-rays under multiple projection angles. A well-known application is medical imaging with a CT-scanner. The reconstruction methods can roughly be divided into two categories: analytical reconstruction methods and algebraic reconstruction methods (ARMs). An example of an algorithm from the first category is Filtered Backprojection (FBP). This method has a high computational efficiency and it performs well in cases with many equiangularly distributed projection angles and high signal-to-noise ratio. ARMs require in general more computation time. They are more robust with respect to noise and can handle few projection angles or a limited angular range better. In this dissertation, the new algorithm Algebraic filter – Filtered Backprojection (AF-FBP) is introduced, which uses an ARM to create filters that can be used in FBP. The reconstruction quality of AF-FBP approximates that of the corresponding (locally) linear ARM, while the reconstructions are obtained with the computational efficiency of FBP. In cases with a small number of different scanning geometries, using AF-FBP enables the reconstruction of images of relatively high quality for few projection angles, limited angular range, or low signal-to-noise ratio.</p>
Micro-cathode thruster for cube satellite propulsion (2012)

Summary form only given. Recently a new device namely micro-cathode arc thruster (μCAT) based on vacuum arc discharge has been developed for the spacecraft propulsion application <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> . The μCAT is a micro-Newton level thrust device that employs a magnetic field and is suited for the long-time operation of micro-thruster for the nano-satellite propulsion such as Cubesats <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2, 3</sup> . We report on experimental measurements of thruster performance characteristics and plasma properties inside and outside of thruster channel. In particular, effect of a magnetic field is studied. The cathode spot motion inside of the thruster channel and the cathode material consumption rate depend significantly the magnetic field applied. It is found that the rotation speed (B=0.3T) is about 100m/s which is 5 time more than that at B=0T. Experiment results show that the magnetic field leads a 3 times (B=0.3) increase of cathode material consumption rate (B=0T), which is the key for increasing thrust. It is also found that the magnetic field increases the total ion output by a factor of 50. The ion velocity increased by factor of two with the magnetic field applied. During the pulse thrust was measured to be about 9 mN at B=0.3T. The efficiency of μCAT has been studied based on the thruster impulse and cathode mass consumption rate measurement results. It is found that over 90% of ions have been fully accelerated with magnetic field applied.
Multiple object detection by sequential monte carlo and Hierarchical Detection Network (2010)

In this paper, we propose a novel framework for detecting multiple objects in 2D and 3D images. Since a joint multi-object model is difficult to obtain in most practical situations, we focus here on detecting the objects sequentially, one-by-one. The interdependence of object poses and strong prior information embedded in our domain of medical images results in better performance than detecting the objects individually. Our approach is based on Sequential Estimation techniques, frequently applied to visual tracking. Unlike in tracking, where the sequential order is naturally determined by the time sequence, the order of detection of multiple objects must be selected, leading to a Hierarchical Detection Network (HDN). We present an algorithm that optimally selects the order based on probability of states (object poses) within the ground truth region. The posterior distribution of the object pose is approximated at each step by sequential Monte Carlo. The samples are propagated within the sequence across multiple objects and hierarchical levels. We show on 2D ultrasound images of left atrium, that the automatically selected sequential order yields low mean detection error. We also quantitatively evaluate the hierarchical detection of fetal faces and three fetal brain structures in 3D ultrasound images.
<title>Signal, noise, and readout considerations in the development of amorphous silicon photodiode arrays for radiotherapy and diagnostic x-ray imaging</title> (1991)

Recent advances in the fabrication of sensors and transistors from hydrogenated amorphous silicon are allowing the creation of flat panel, large area, radiation-damage-resistant arrays for radiotherapy and diagnostic imaging. A straightforward application of available a-Si:H technology involves the configuration of photodiode sensors coupled with field effect transistors into regular 2-dimensional pixel patterns. While the specifications of the array design must be tailored to the demands of the imaging application, the design is at the same time constrained by various array parameters. Considerations affecting choices for these parameters and how they relate to the signal, noise, and readout properties of radiotherapy arrays are presented and some initial data reported. Implications for a-Si:H diagnostic imagers are discussed.
Aircraft Hydraulic System Leakage Detection and Servicing Recommendations Method (2014)

Aircraft hydraulic systems are composed of several components connected and distributed along the aircraft. Monitoring leakage of these components are time-consuming tasks, and often cover only some parts of the system. The objective of this work is to present a method to estimate hydraulic leakage and recommend maintenance and servicing tasks using aircraft standard sensors such as fluid temperature and reservoir level.The proposed method was tested using several aircraft operating data with different levels of degradation (external leakages) and the results were analyzed in order to evaluate its precision on estimating leakage. Results showed the capability to detect leakage although uncertainties must be considered when evaluating maintenance interventions.
Time-Shifted Streaming in a Peer-to-Peer Video Multicast System (2009)

We propose a peer-to-peer (P2P) streaming system that allows users to individually pause and resume a live video stream as well as to view video that was streamed before the particular user joined the session. Such time-shifted streaming can be provided by caching a portion of the video stream at each peer and serving it asynchronously. We analyze the availability of video contents in the P2P overlay using a Poisson model of peer arrival. We also discuss fast prefetching, which reduces video disruption due to peer churn and also allows peers to disseminate content more quickly, thus reducing server bandwidth requirement. We extend the Stanford Peer-to-Peer Multicast (SPPM) protocol to support time-shifted streaming. The overlay is constructed by selecting parent nodes that are expected to most effectively support fast prefetching. Extensive network experiments show that fast prefetching effectively supports time-shifted streaming with reduced server load.
Azobenzene-based solar thermal energy storage enhanced by gold nanoparticles for rapid, optically-triggered heat release at room temperature (2020)

The energy storage and heat release of this STF sample can be controlled completely using light alone at room temperature.
Learning the Dependency Structure of Latent Factors (2012)

In this paper, we study latent factor models with dependency structure in the la-tent space. We propose a general learning framework which induces sparsity on the undirected graphical model imposed on the vector of latent factors. A novel latent factor model SLFA is then proposed as a matrix factorization problem with a special regularization term that encourages collaborative reconstruction. The main benefit (novelty) of the model is that we can simultaneously learn the lower-dimensional representation for data and model the pairwise relationships between latent factors explicitly. An on-line learning algorithm is devised to make the model feasible for large-scale learning problems. Experimental results on two synthetic data and two real-world data sets demonstrate that pairwise relationships and latent factors learned by our model provide a more structured way of exploring high-dimensional data, and the learned representations achieve the state-of-the-art classification performance. 1
First-trimester vaginal microbiome diversity: A potential indicator of preterm delivery risk (2017)

Preterm birth is a leading cause of global neonate mortality. Hospitalization costs associated with preterm deliveries present a huge economic burden. Existing physical/biochemical markers for predicting preterm birth risk are mostly suited for application at mid/late pregnancy stages, thereby leaving very short time (between diagnosis and delivery) for adopting appropriate intervention strategies. Recent studies indicating correlations between pre/full-term delivery and the composition of vaginal microbiota in pregnant women have opened new diagnostic possibilities. In this study, we performed a thorough meta-analysis of vaginal microbiome datasets to evaluate the utility of popular diversity and inequality measures for predicting, at an early stage, the risk of preterm delivery. Results indicate significant differences (in diversity measures) between 'first-trimester' vaginal microbiomes obtained from women with term and preterm outcomes, indicating the potential diagnostic utility of these measures. In this context, we introduce a novel diversity metric that has significantly better diagnostic ability as compared to established diversity measures. The metric enables 'early' and highly accurate prediction of preterm delivery outcomes, and can potentially be deployed in clinical settings for preterm birth risk-assessment. Our findings have potentially far reaching implications in the fight against neonatal deaths due to preterm birth.
PN code acquisition using signed-rank-based nonparametric detectors in DS/SS systems (2001)

In this paper, signed-rank based nonparametric detectors are used for pseudonoise (PN) code acquisition in direct-sequence spread-spectrum (DS/SS) systems. We first derive the locally optimum rank (LOR) detector and then propose the locally suboptimum rank (LSR) and modified signed-rank (MSR) detectors using approximate score functions. We compare the single-dwell scheme without the verification mode using the proposed LSR and MSR detectors with that using the conventional squared-sum (SS) and modified sign (MS) detectors. From the simulation results, it is shown that the proposed LSR and MSR detectors perform better than the MS detector by about 2-3 dB and are nearly optimum.
A compact fiber-to-waveguide coupler based on angled slots (2005)

We present a compact grating coupler, consisting of slanted air slots, for coupling from single-mode fiber to InP-based waveguides. The theoretical coupling efficiency is better than 50% and first fabrication experiments are promising. (2 pages)
Synthesis of Novel N4-Hydrocytidine Analogs as Potential Anti-SARS-CoV-2 Agents (2022)

Coronavirus disease 2019 (COVID-19) is an emerging global pandemic with severe morbidity and mortality caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Molnupiravir, an ester prodrug form of <i>N</i><sup>4</sup>-hydroxycytidine (NHC), was recently emergency-use approved for the treatment of early SARS-CoV-2 infections. Herein, we report the synthesis and evaluation of a series of novel NHC analogs.
Design and modeling of communications system for interoperable positive train control (2010)

Positive train control (PTC) provides a critical safety backup for train operations to protect against the consequences of human error. With the Rail Safety Improvement Act of 2008 mandating positive train control for most North American railroads, railroad community efforts are underway to develop an interoperable PTC communications system over a 220 MHz network. A robust, reliable, and interoperable communications system is one the most vital components to the success of the PTC technology. This paper presents the design and modeling of a 220 MHz interoperable PTC system. The paper introduces a communication protocol that is designed to efficiently meet PTC communications needs within the available 220 MHz spectrum. The paper also presents simulation system architecture for analyzing the performance of the 220 MHz PTC system. Extensive simulations are conducted to evaluate the system performance and validate the design.
Orthogonal processing: A new strategy for organic electronics (2011)

The concept of chemical orthogonality has long been practiced in the field of inorganic semiconductor fabrication, where it is necessary to deposit and remove a layer of photoresist without damaging the underlying layers. However, these processes involving light sensitive polymers often damage organic materials, preventing the use of photolithography to pattern organic electronic devices. In this article we show that new photoresist materials that are orthogonal to organics allow the fabrication of complex devices, such as hybrid organic/inorganic circuitry and full-colour organic displays. The examples demonstrate that properly designed photoresists enable the fabrication of organic electronic devices using existing infrastructure.
Simultaneous transducers for data-parallel XML parsing (2008)

Though XML has gained significant acceptance in a number of application domains, XML parsing can still be a vexing performance bottleneck. With the growing prevalence of multicore CPUs, parallel XML parsing could be one option for addressing this bottleneck. Achieving data parallelism by dividing the XML document into chunks and then independently processing all chunks in parallel is difficult, however, because the state of an XML parser at the first character of a chunk depends potentially on the characters in all preceding chunks. In previous work, we have used a sequential preparser implementing a preparsing pass to determine the document structure, followed by a parallel full parse. The preparsing is sequential, however, and thus limits speedup. In this work, we parallelize the preparsing pass itself by using a simultaneous finite transducer (SFT), which implicitly maintains multiple preparser results. Each result corresponds to starting the preparser in a different state at the beginning of the chunk. This addresses the challenge of determining the correct initial state at beginning of a chunk by simply considering all possible initial states simultaneously. Since the SFT is finite, the simultaneity can be implemented efficiently simply by enumerating the states, which limits the overhead. To demonstrate effectiveness, we use an SFT to build a parallel XML parsing implementation on an unmodified version of libxml2, and obtained good scalability on both a 30 CPU Sun E6500 machine running Solaris and a Linux machine with two Intel Xeon L5320 CPUs for a total of 8 physical cores.
Method For The Production Of Polyunsaturated Fatty Acids (Patent CA 2510462 A1) (2004)

The present invention relates to an improved process for the specific production of poly-unsaturated omega-3 and omega-6 fatty acids and a process for the production of triglycerides having an increased content of unsaturat ed fatty acids, in particular omega-3 and omega-6 fatty acids having at least t wo double bonds and a 20 or 22 carbon atom chain length. The invention relates to the produc-tion of a transgenic organism, preferably a transgenic plant or a transgenic microorganism, hav-ing an increased content of fatty acids, oils or lipids containing C20- or C22- fatty acids with a delta-5, 7, 8, 10 double bond, respectively due to the expression of a delta-8-desaturase and a delta -9- elon-gase from organisms such as plants preferably Algae like Isochrysis galbana or Euglena gracilis. In addition the invention relates to a process for the production of poly unsaturated fatty acids such as Eicosapentaenoic, Arachidonic, Docosapentaenoic or Docosahexaenoic acid through the co- expression of a delta -8-desaturase, a delta-9-elongase and a delta-5 desaturase in organisms such as microorganisms or plants.The invention additionally relates to the use of specific nucleic acid sequences encoding for the aforementioned proteins with delta-8-desaturase-, delta-9-elongase- or delta-5-desaturase-activity, nucleic acid constructs, vectors and organisms containing said nucleic acid sequences. The invention further relates to unsaturated fatty acids and triglycerides having an increased content of at least 1 % by weight of unsaturated fatty acids and use thereof.\n\n
Reaction-Based Fluorescent Probes for Selective Imaging of Hydrogen Sulfide in Living Cells (2011)

Hydrogen sulfide (H(2)S) is emerging as an important mediator of human physiology and pathology but remains difficult to study, in large part because of the lack of methods for selective monitoring of this small signaling molecule in live biological specimens. We now report a pair of new reaction-based fluorescent probes for selective imaging of H(2)S in living cells that exploit the H(2)S-mediated reduction of azides to fluorescent amines. Sulfidefluor-1 (SF1) and Sulfidefluor-2 (SF2) respond to H(2)S by a turn-on fluorescence signal enhancement and display high selectivity for H(2)S over other biologically relevant reactive sulfur, oxygen, and nitrogen species. In addition, SF1 and SF2 can be used to detect H(2)S in both water and live cells, providing a potentially powerful approach for probing H(2)S chemistry in biological systems.
Making Activated Carbon for Storing Gas (2005)

Solid disks of microporous activated carbon, produced by a method that enables optimization of pore structure, have been investigated as means of storing gas (especially hydrogen for use as a fuel) at relatively low pressure through adsorption on pore surfaces. For hydrogen and other gases of practical interest, a narrow distribution of pore sizes <2 nm is preferable. The present method is a variant of a previously patented method of cyclic chemisorption and desorption in which a piece of carbon is alternately (1) heated to the lower of two elevated temperatures in air or other oxidizing gas, causing the formation of stable carbon/oxygen surface complexes; then (2) heated to the higher of the two elevated temperatures in flowing helium or other inert gas, causing the desorption of the surface complexes in the form of carbon monoxide. In the present method, pore structure is optimized partly by heating to a temperature of 1,100 C during carbonization. Another aspect of the method exploits the finding that for each gas-storage pressure, gas-storage capacity can be maximized by burning off a specific proportion (typically between 10 and 20 weight percent) of the carbon during the cyclic chemisorption/desorption process.
Compaction-based test generation using state and fault information (2002)

Presents a new test generation procedure for sequential circuits using newly-traversed state information and newly-detected fault information obtained between successive iterations of vector compaction. Two types of technique are considered. One is based on which new states a sequential circuit is driven into, and the other is based on the new faults that are detected in the circuit between consecutive iterations of vector compaction. These data modify an otherwise random selection of vectors to bias vector sequences that cause the circuit to reach new states and cause previously undetected faults to be detected. The biased vectors, when used to extend the compacted test set, provide an intelligent selection of vectors. The extended test set is then compacted. Repeated applications of state and fault analysis, vector generation and compaction produce significantly high fault coverage using relatively small computing resources. We obtained improvements in terms of higher fault coverage, fewer vectors for the same coverage, or smaller numbers of iterations and time required, consistently for several benchmark circuits.