gebhart/patrepeval huggingface dataset:
Self-crossed field ion sources (1974)

To obtain an intense ion beam from various kinds of materials, a new PIG type ion source without external magnetic field has been designed and operating characteristics have been studied. In an ordinary type of ion source, voltages are applied to electrodes such as the anode, filament, and extractor under the crossed magnetic field. If a spiral filament or anode is used and heavy DC current flows through the electrode keeping the potential relationship between the filament, anode, and extractor electrodes constant, a magnetic field due to the heavy current can be used effectively for the ionization of materials. Since the magnetic field produced by the electrode system is crossed with an electric field, a new PIG type ion source is obtained which may be called a self-crossed field ion source. Basically, two types of the self-crossed field ion source are proposed. One is the outer filament coil type in which the crossed field is constructed from filament current; the other is an outer helical anode type constructed from spiral anode current. Since the self-crossed ion source has a simple and compact structure without an external magnetic coil, the source is suitable to operate under high temperature and to introducemore » microwave or RF power. To get an intense ion beam, these ion source units can operate in parallel. Therefore, many new application fields can be expected. (auth)« less
Recent Norway rats studies using warfarin (1998)

Warfarin resistance in the Norway rat (Rattus norvegicus) has been studied over the past 30 years. To determine the status of this resistance phenomenon wild Norway rats were collected from Colorado and Chicago, Illinois. As reported previously, warfarin resistance in the Chicago area exceeds 50%, while rats from Colorado remain very susceptible to warfarin. The theory that true genetic resistance may not exist was examined, implying that geographic variation in intestinal flora contribute to the rapid degradation of warfarin after ingestion, along with production of sufficient Vitamin K in the bacteria to reverse the effect of warfarin. Antibiotics in combination were tested with warfarin and demonstrated that efficacy in the laboratory can be increased by using the combination in a bait form.
Identification of a Species Specific Regulatory Site in Human Pancreatic Cholesterol Esterase (1995)

All mammalian pancreatic cholesterol esterases (CEase) bind to membrane-associated heparin at a single site on the intestinal brush border membrane with a dissociation constant of 100 nM. While the enzyme is bound to the membrane, the activity of the human and bovine enzymes is enhanced 2-fold when compared to the activity of the enzyme in solution. On the other hand, soluble heparin potently inhibits the human CEase-catalyzed hydrolysis of cholesterol oleate with an IC50 of 2 x 10(-4) mg/mL, a value that is about 10(4) times more potent than that found with the bovine enzyme. The C-terminal portion of the human enzyme contains 16 proline-rich repeats of 11 amino acids each, while that from other species contains only a few of these repeat units. To determine if the unique human C-terminus is responsible for this inhibition, two chimeras containing either the human N-terminus (residues 1-445) and the bovine C-terminus (residues 446-557), HB, or the bovine N-terminus (residues 1-445) and the human C-terminus (residues 446-722), BH, were prepared. The cholesterol oleate hydrolytic activity of these chimeras was similar to that for the recombinant human and bovine enzymes. Importantly, each chimera was inhibited by heparin with IC50 values of 0.03 and 0.1 mg/mL for HB and BH, respectively. These intermediate IC50 values indicate that human CEase has two structural regions that contribute to is unique inhibition by this sulfated glycosaminoglycan, and these could regulate cholesterol uptake in humans.
Analyzing the suitability of web applications for a single-user to multi-user transformation (2013)

Multi-user web applications like Google Docs or Etherpad are crucial to efficiently support collaborative work (e.g. jointly create texts, graphics, or presentations). Nevertheless, enhancing single-user web applications with multi-user capabilities (i.e. document synchronization and conflict resolution) is a time-consuming and intricate task since traditional approaches adopting concurrency control libraries (e.g. Apache Wave) require numerous scattered source code changes. Therefore, we devised the Generic Collaboration Infrastructure (GCI) [8] that is capable of converting single-user web applications non-invasively into collaborative ones, i.e. no source code changes are required. In this paper, we present a catalog of vital application properties that allows determining if a web application is suitable for a GCI transformation. On the basis of the introduced catalog, we analyze 12 single-user web applications and show that 6 are eligible for a GCI transformation. Moreover, we demonstrate (1) the transformation of one qualified application, namely, the prominent text editor TinyMCE, and (2) showcase the resulting multi-user capabilities. Both demo parts are illustrated in a dedicated screencast that is available at http://vsr.informatik.tu-chemnitz.de/demo/TinyMCE/.
Efficient quantitative phase microscopy using programmable annular LED illumination (2017)

In this work, we present an efficient quantitative phase imaging (QPI) approach using programmable annular LED illumination. As a new type of coded light source, the LED array provides flexible illumination control for noninterferometric QPI based on a traditional microscopic configurations. The proposed method modulates the transfer function of system by changing the LED illumination pattern, which provides noise-robust response of transfer function and achieves twice resolution limit of objective NA. The quantitative phase can be recovered from slightly defocused intensity images through inversion of transfer function. Moreover, the weak object transfer function (WOTF) of axis-symmetric oblique source is derived, and the noise-free and noisy simulation results validate the predicted theory. Finally, we experimentally confirm accurate and repeatable performance of our method by imaging calibrated phase samples and cellular specimens with different NA objectives.
High-contrast positive resists for e-beam mask making (1998)

The five major requirements for electron beam resists for chrome mask fabrication include high resolution, high speed, RIE etch resistance, thermal bake insensitivity, and long coated plate shelf life. High speed, high resolution and good RIE resistance are common attributes of chemically amplified resists (CAR) used primarily for Deep UV lithography. However, the environmental susceptibility to airborne amines, need for a long coated plate shelf life and the requirement for 140 Celsius postexpose bake (PEB) of some CAR or fundamental challenges of these families of resist for practical Cr lithography. We have been developing a series of fast amplified e beam resists which exhibit do not require PEB bake and are tolerant of airborne contaminants. The shelf life attributes of both negative and positive chemically amplified resists was examined and found to be susceptible to absorption of moisture. Some of the acid generators hydrolyzed in the dried films and led to changes in resist sensitivity or dark film loss. Long term film stability of CAR coated plates can be promoted by using hydrophobic solvents, stable acid generators, and most effectively by storage under anhydrous conditions.
Effect of voltage sags on adjustable speed drives-a critical evaluation and an approach to improve its performance (1999)

In this paper, a critical evaluation of the effect of voltage sags on adjustable speed drives (ASDs) is presented. In particular the DC-link voltage variation under voltage sag and its dependence on source impedance, DC-link inductance and output load is computed. It is shown that for larger source impedance, the DC-link voltage variation under a voltage sag is also large and increases the susceptibility of an ASD and may result in a nuisance trip. The results from the analysis are plotted in per unit quantities and serve as a design guide to assess ASD performance for a variety of sags. In order to improve the performance of ASDs, this paper proposes an integrated boost converter approach. This approach provides ridethrough to critical ASD load during voltage sags without any additional energy storage device. Upon detection of a voltage sag the boost converter operates with suitable duty ratio and maintains the DC-link voltage within acceptable limits. This prevents nuisance tripping and facilitates continuous operation of critical ASD load at rated torque. The proposed integrated boost converter does not introduce any additional semiconductors in the series path of the power flow and is low in cost. A commercially available 480 V, 22 kVA ASD is modified with the integrated boost converter approach and details are discussed. Analysis, simulation and experimental performance of the ridethrough approach are presented.
Presence of Multiple Functional Polyadenylation Signals and a Single Nucleotide Polymorphism in the 3′ Untranslated Region of the Human Serotonin Transporter Gene (1999)

The human serotonin transporter (hSERT) gene is a candidate for involvement in the aetiology of affective disorders. In humans, multiple transcripts of the gene have been detected by northern blot analysis of brain and other tissues. We performed 3' rapid amplification of cDNA ends to identify the common sites of polyadenylation in hSERT mRNA from human JAR cells and whole blood. Two major polyadenylation sites were identified: one 567 bp downstream of the stop codon, consistent with the usage of the polyadenylation signal AATGAA, and a second site 690 bp downstream of the stop codon. The putative polyadenylation signal upstream of this site contained a single nucleotide polymorphism (AG/TTAAC). However, allelic variation at this site did not influence polyadenylation site usage, and there were no significant differences in the abundance of the two alleles of this polymorphism between 329 control subjects, 158 individuals with major depression, and 130 individuals with bipolar affective disorder. This single nucleotide polymorphism in the 3' untranslated region of the hSERT gene should provide a useful genetic marker in the evaluation of hSERT as a candidate gene influencing susceptibility to mood disorders.
Total Synthesis of the Potent Microtubule-Stabilizing Agent (+)-Discodermolide (2003)

The total synthesis of the potent microtubule-stabilizing, antimitotic agent (+)-discodermolide is described. The convergent synthetic strategy takes advantage of the diastereoselective alkylation of a ketone enolate to establish the key C15-C16 bond. The synthesis is amenable to preparation of gram-scale quantities of (+)-discodermolide and analogues.
Ambiguity-function generation using passive optical τ-shift technique (1980)

A new technique of optical spatial integration is presented. Its key feature lies in the utilization of one-dimensional input-data transducers to create the two-dimensional ambiguity map through an optical architecture in which the τ axis is passively created.
High-resolution X-ray diffraction with no sample preparation (2017)

It is shown that energy-dispersive X-ray diffraction (EDXRD) implemented in a back-reflection geometry is extremely insensitive to sample morphology and positioning even in a high-resolution configuration. This technique allows high-quality X-ray diffraction analysis of samples that have not been prepared and is therefore completely non-destructive. The experimental technique was implemented on beamline B18 at the Diamond Light Source synchrotron in Oxfordshire, UK. The majority of the experiments in this study were performed with pre-characterized geological materials in order to elucidate the characteristics of this novel technique and to develop the analysis methods. Results are presented that demonstrate phase identification, the derivation of precise unit-cell parameters and extraction of microstructural information on unprepared rock samples and other sample types. A particular highlight was the identification of a specific polytype of a muscovite in an unprepared mica schist sample, avoiding the time-consuming and difficult preparation steps normally required to make this type of identification. The technique was also demonstrated in application to a small number of fossil and archaeological samples. Back-reflection EDXRD implemented in a high-resolution configuration shows great potential in the crystallographic analysis of cultural heritage artefacts for the purposes of scientific research such as provenancing, as well as contributing to the formulation of conservation strategies. Possibilities for moving the technique from the synchrotron into museums are discussed. The avoidance of the need to extract samples from high-value and rare objects is a highly significant advantage, applicable also in other potential research areas such as palaeontology, and the study of meteorites and planetary materials brought to Earth by sample-return missions.
Space–Time Trellis Codes Based on Channel-Phase Feedback (2006)

Space-time coding (STC) has been proposed recently for multiple-antenna wireless communication systems. Most of the proposed STC schemes use the assumption that either no channel-state information, or the channel mean/covariance information, is available at the transmitter. In this paper, we propose a new STC scheme for a closed-loop transmission system, where quantized channel-phase information is available at the transmitter. A new performance criterion is derived for the quasi-static fading channel. This design criterion is then used to construct a new class of space-time trellis codes (STTCs). The proposed code construction is based on the concatenation of a standard multiple trellis-coded modulation outer code with an inner code. The inner code is selected from a series of inner codes using the channel-phase feedback. The series of inner codes are constructed based on the systematic set partitioning of several classes of space-time signal designs. Simulation results show significant performance improvement over the other STTCs in the literature. In addition, the proposed coding scheme enjoys low peak-to-average-power ratio, simple decoding, and power-efficient low-cost implementation
Thin‐Layer Chromatographic Enantiomeric Resolution via Ligand Exchange (1984)

Racemic amino acids can be resolved straightforwardly and rapidly using thinlayer chromatography. Decisive in this respect is that the TLC plates are impregnated with the chiral selector 1. The method also enables the determination of the enantiomeric purity of amino acids.
T cell epitopes derived from autoantigens are selected differently than those from exogenous antigens (130.15) (2010)

Abstract We have established a novel minimalist cell-free MHC class II antigen-processing system for identifying immunodominant epitopes from protein antigens. The system constitutes HLA-DR1, HLA-DM (DM) and three cathepsins. This system not only identifies the immunogenic epitopes from complex protein antigens, but also provides insight to the mechanism of immunodominance. Understanding of how these immunogenic epitopes are selected certainly provides better strategies for developing effective peptide vaccine designs and therapies against infectious diseases, cancer, autoimmune diseases and allergy. Using our cell-free system, and based on the source of the antigens categorized as exogenous antigens versus autoantigens, we find that both DM and cathepsins are crucial in regulating the selection of immunodominant epitopes. Three types of determinants are generated: first, non-dominant epitopes that are sensitive to both DM mediated dissociation, and cathepsins digestion. These epitopes were eliminated immediately from peptide repertoire. Second, T cell epitopes derived from the exogenous antigen are DM resistant and cathepsin sensitive. Third, T cells epitopes derived from an antoantigen that are sensitive to DM mediated dissociation, but resistant to cathepsin digestion. This shows that generation of immunodominant epitopes is regulated differently depending on the source of proteins antigens.
Distributed RankBoost Acceleration Using FPGA and MPI for Web Relevance Ranking (2008)

Web search engine ranks web pages according to their relevance to user queries, which is critical for the success of commercial search engines. Rank Boost algorithm is promising in Web relevance ranking area, while its computation complexity makes our existing implementations (including single node software-based implementation and a FPGA-based accelerator) too slow to reflect the dynamics of the Web. Moreover, previous implementations can not handle the huge web-scale data. As such, in this paper, we present the RankBoost implementation on a MPI-based distributed FPGA-based accelerators. Our results show that the combination of the coarse parallel efficiency of distributed system and the fine parallel efficiency of reconfigurable hardware accelerators can significantly increase the computing performance.
Fluorescence optical tomography using independent component analysis to detect small targets in turbid media (2005)

A new approach for optical fluorescence tomographic imaging of targets in a turbid medium that uses the independent component analysis (ICA) from information theory is presented. Fluorescence signals from targets embedded in a turbid medium are measured on the boundary of the medium using a multi-source excitation and a multi-detector acquisition scheme. Differences between excitation and fluorescence wavelengths enable sensitive, minimal-background signal acquisition. ICA of the fluorescence signal on the medium boundary sorts out the embedded ob-jects, and their locations are obtained from Green’s function analysis based on any appropriate light propagation model. Fluorescence tomographic imaging experiments were carried out using Intralipid-10% suspension in water contained in a 50-mm thick rectangular transparent plastic cell as the turbid medium, and small glass spheres containing indocyanine green (ICG) solution as fluorescent targets. The near-infrared (NIR) fluorescence was excited using 785 nm light, and monitored over a narrow band around 830 nm. The transport mean free paths at 785 nm and 830 nm were 1.01 mm and 1.14 mm, respectively. The approach could image and determine the position of an ICG filled sphere of radius as small as 4 mm. It is applicable to small objects, different medium geometries, and amenable to near real time imaging applications.
Ferromagnetic-ferromagnetic tunneling and the spin filter effect (1994)

Tunneling characteristics of a ferromagnetic-antiferromagnetic-ferromagnetic (FM-AFM-FM) thin film tunnel junction were studied in high magnetic fields with a view to investigate magnetic coupling by the tunneling process. Gd2O3, a stable oxide which undergoes antiferromagnetic ordering below about 3.9 K, was chosen as the tunnel barrier between the ferromagnetic electrodes Gd and permalloy. Tunnel characteristics showed as much as 32% decrease in junction resistance in an applied field of 20 T, below 4.2 K. The resistance behavior as a function of H can be explained by two different effects: firstly, the change in tunnel conductance due to change in the relative magnetization of the two FM electrodes in low H; secondly, the spin filter effect in high fields, due to the exchange splitting of the Gd2O3 conduction band.
Acoustic obstructive sleep apnea detection (2009)

Obstructive sleep apnea (OSA) is a common respiratory disorder during sleep, in which the airways are collapsed and impair the respiration. Apnea is s cessation of airflow to the lungs which lasts at least for 10s. The current gold standard method for OSA assessment is full night polysomnography (PSG); however, its high cost, inconvenience for patients and immobility have persuaded researchers to seek simple and portable devices to detect OSA. In this paper, we report on developing a new system for OSA detection and monitoring, which only requires two data channels: tracheal breathing sounds and the blood oxygen saturation level (S(a)O(2)). A fully automated method was developed that uses the energy of breathing sounds signals to segment the signals into sound and silent segments. Then, the sound segments are classified into breath, snore (if exists) and noise segments. The S(a)O(2) signal is analyzed to find the rises and drops in the S(a)O(2) signal. Finally, a fuzzy algorithm was developed to use this information and detect apnea and hypopnea events. The method was evaluated on the data of 40 patients simultaneously with full night PSG study, and the results were compared with those of the PSG. The results show high correlation (96%) between our system and PSG. Also, the method has been found to have sensitivity and specificity values of more than 90% in differentiating simple snorers from OSA patients.
Three-dimensional reconstruction of microcalcification clusters from two mammographic views (2001)

Classification of benign/malignant microcalcification clusters is a major diagnostic challenge for radiologists. Clinical studies have revealed that the shape of the cluster, and the spatial distribution of individual microcalcifications within it, are important indicators of its malignancy. However, mammographic images of clustered microcalcifications confound their three-dimensional (3-D) distribution with image projection and breast compression. This paper presents a novel model-based method for reconstructing microcalcification clusters in 3-D from two mammographic views (cranio-caudal and medio-lateral oblique--"shoulder to the opposite hip" or lateral-medio). We develop a 3-D breast representation and a parameterised breast compression model which constraints geometrically the possible 3-D positions of a calcification in a two-dimensional image. Corresponding calcifications in the two views are matched using an estimate of the calcification volume. Both the geometric constraint and the matching criterion are utilized in the final reconstruction step to build the 3-D reconstructed clusters. Validation experiments are described using 30 clusters to verify the individual steps of the model, and results consistent with known ground truth are obtained. Some of the approximations in the model and future work are discussed in the concluding section.
Malware provenance: code reuse detection in malicious software at scale (2016)

Detecting code reuse in software has applications in malicious code analysis and in malware code search and retrieval, but is complicated by the lack of available source code. In this paper, we examine the methods for detecting similarity using the First Byte instruction block normalization approach proposed previously, but examine the performance and characteristics of the proposed Locality Sensitive Hashing (LSH) scheme for search and retrieval. We demonstrate that our approach allows for the construction of new super signatures without the availability of the original malware input and that signatures from constituent malware blocks can be used to construct signatures of malware variants. We compare our approach with other projects that propose a similar method and show the effectiveness of our approach with regards to a known malware dataset. Experimental results show that our approach is advantageous in detection accuracy and comparison time.
Digital PWM controller and current estimator for a low-power switching converter (2002)

This paper describes design and implementation of a digital controller for an experimental low-power converter in a battery-powered system with power management. Multiple operating modes are used to maintain high efficiency over wide ranges of input voltages and loads. A current estimation technique to perform load-dependent mode switching is proposed and tested. A digital PID regulator design example is described, with emphasis on practical limitations imposed by the fixed-point arithmetic and the delay due to sampling and processing.