gebhart/patrepeval huggingface dataset:
Dispersion and Field Analysis of a Microstrip Meander-Line Slow-Wave Structure (1974)

A structure which is important as an example of a spatially periodic medium for microwave propagation is analyzed theoretically, with rigorous consideration of its partial dielectric composition, symmetry properties; and field configuration relating to its use for electron-wave interaction in a crossed-field amplifier (CFA). The analysis is carried out in a quasi-TEM approximation, leading to determination of a complex potential function within the unit cell and the associated normal-mode parameters: effective dielectric constant, phase velocity, and characteristic impedance, as functions of phase per cell and mode symmetry. With imposition of meander-line boundary conditions, solutions of the characteristic equation for the dispersion law of the structure are computed, including the influence of the inhomogeneous dielectric-vacuum construction of microstrip. Agreement with the observed phase and stopband features of a representative structure is very good. Power distribution and group velocity are calculated, and an interaction impedance, representing the coupling between the RF field and an electron beam for estimation of CFA performance is also calculated. The method lends itself to detailed computations, including the effects of structural features of practical slow-wave circuits.
Efficient UC-Secure Authenticated Key-Exchange for Algebraic Languages. (2012)

Authenticated Key Exchange (AKE) protocols enable two parties to establish a shared, cryptographically strong key over an insecure network using various authentication means, such as cryptographic keys, short (i.e., lowentropy) secret keys or credentials. In this paper, we provide a general framework, that encompasses several previous AKE primitives such as (Verifier-based) Password-Authenticated Key Exchange or Secret Handshakes, we call LAKE for Language-Authenticated Key Exchange. We first model this general primitive in the Universal Composability (UC) setting. Thereafter, we show that the Gennaro-Lindell approach can efficiently address this goal. But we need smooth projective hash functions on new languages, whose efficient implementations are of independent interest. We indeed provide such hash functions for languages defined by combinations of linear pairing product equations. Combined with an efficient commitment scheme, that is derived from the highly-efficient UC-secure Lindell’s commitment, we obtain a very practical realization of Secret Handshakes, but also Credential-Authenticated Key Exchange protocols. All the protocols are UC-secure, in the standard model with a common reference string, under the classical Decisional Linear assumption.
Novel method for converting digital Fresnel hologram to phase-only hologram based on bidirectional error diffusion (2013)

We report a novel and fast method for converting a digital, complex Fresnel hologram into a phase-only hologram. Briefly, the pixels in the complex hologram are scanned sequentially in a row by row manner. The odd and even rows are scanned from opposite directions, constituting to a bidirectional error diffusion process. The magnitude of each visited pixel is forced to be a constant value, while preserving the exact phase value. The resulting error is diffused to the neighboring pixels that have not been visited before. The resulting novel phase-only hologram is called the bidirectional error diffusion (BERD) hologram. The reconstructed image from the BERD hologram exhibits high fidelity as compared with those obtained with the original complex hologram.
A DOA Based Speaker Diarization System for Real Meetings (2008)

This paper presents a speaker diarization system that estimates who spoke when in a meeting. Our proposed system is realized by using a noise robust voice activity detector (VAD), a direction of arrival (DOA) estimator, and a DOA classifier. Our previous system utilized the generalized cross correlation method with the phase transform (GCC-PHAT) approach for the DOA estimation. Because the GCC-PHAT can estimate just one DOA per frame, it was difficult to handle speaker overlaps. This paper tries to deal with this issue by employing a DOA at each time-frequency slot (TFDOA), and reports how it improves diarization performance for real meetings / conversations recorded in a room with a reverberation time of 350 ms.
Solvothermal Synthesis of Platinum Alloy Nanoparticles for Oxygen Reduction Electrocatalysis (2012)

Platinum alloy nanoparticles show great promise as electrocatalysts for the oxygen reduction reaction (ORR) in fuel cell cathodes. We report here on the use of N,N-dimethylformamide (DMF) as both solvent and reductant in the solvothermal synthesis of Pt alloy nanoparticles (NPs), with a particular focus on Pt-Ni alloys. Well-faceted alloy nanocrystals were generated with this method, including predominantly cubic and cuboctahedral nanocrystals of Pt(3)Ni, and octahedral and truncated octahedral nanocrystals of PtNi. X-ray diffraction (XRD) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), coupled with energy dispersive spectroscopy (EDS), were used to characterize crystallite morphology and composition. ORR activities of the alloy nanoparticles were measured with a rotating disk electrode (RDE) technique. While some Pt(3)Ni alloy nanoparticle catalysts showed specific activities greater than 1000 μA/cm(2)(Pt), alloy catalysts prepared with a nominal composition of PtNi displayed activities close to 3000 μA/cm(2)(Pt), or almost 15 times that of a state-of-the-art Pt/carbon catalyst. XRD and EDS confirmed the presence of two NP compositions in this catalyst. HAADF-STEM examination of the PtNi nanoparticle catalyst after RDE testing revealed the development of hollows in a number of the nanoparticles due to nickel dissolution. Continued voltage cycling caused further nickel dissolution and void formation, but significant activity remained even after 20,000 cycles.
Lichen-Like Symbiosis 600 Million Years Ago (2005)

The fossil record of fungi and lichens is scarce. Here we report the discovery of lichen-like fossils, involving filamentous hyphae closely associated with coccoidal cyanobacteria or algae, preserved in marine phosphorite of the Doushantuo Formation (between 551 and 635 million years old) at Weng'an, South China. These fossils indicate that fungi developed symbiotic partnerships with photoautotrophs before the evolution of vascular plants.
Synthesis of 3-Methyl Isoquinolines (1953)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of 3-Methyl IsoquinolinesT. R. Govindachari and B. R. PaiCite this: J. Org. Chem. 1953, 18, 10, 1253–1262Publication Date (Print):October 1, 1953Publication History Published online1 May 2002Published inissue 1 October 1953https://pubs.acs.org/doi/10.1021/jo50016a004https://doi.org/10.1021/jo50016a004research-articleACS PublicationsRequest reuse permissionsArticle Views262Altmetric-Citations10LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Specific interaction of camptothecin, a topoisomerase I inhibitor, with guanine residues of DNA detected by photoactivation at 365 nm (1993)

Camptothecin-induced DNA photolesions were examined after UVA irradiation at 365 nm. DNA single-strand breaks were induced both in supercoiled and in relaxed SV40 DNA. In uniquely end-labeled human c-myc DNA, camptothecin-induced cleavage occurred exclusively at guanines and was markedly enhanced by hot piperidine treatment. Runs of polyguanines were the most cleaved, especially in their 5' flank. Primer extension experiments in the absence of piperidine treatment confirmed these results and did not show additional lesions. We found that synthetic single-stranded oligonucleotides were more reactive than duplex oligonucleotides. In addition, an excess of dideoxyguanosine triphosphates competed for camptothecin-induced DNA photolesions. Therefore, camptothecin stacking in DNA grooves is more likely than genuine drug intercalation. Groove shielding with sodium or magnesium reduced camptothecin-induced photodamage while minor groove occupancy with spermine extended damages. Photolesion mechanisms were investigated using scavengers. In aerobic conditions, the most effective scavengers were thiourea, sodium azide, and catalase. Protection by superoxide dismutase was weak, and mannitol was ineffective. In anaerobic conditions, lesions were more extensive. Taken together, these results show that photoactivated camptothecin interacts specifically and intimately with guanines. This finding is consistent with preferential stimulation of topoisomerase I cleavage at sites that bear a guanine at their 5'-DNA terminus [Jaxel, C., et al. (1991) J. Biol. Chem. 266, 1465-1469] and with the camptothecin stacking model at topoisomerase I DNA cleavage sites.
Gain calibrating nonuniform image-array data using only the image data (1991)

An algorithm is developed for calibrating the spatial nonuniformity of image-array (CCD-type) detectors. Like other techniques this approach uses multiple, spatially displaced images. In circumstances where high-precision flat fields are not available by other means (i.e., sky flats) this technique is advantageous as it uses the data frames for gain calibration even when the array images extended, nonuniform, sources. Numerical experiments and direct observations with intrinsically uniform and quite nonuniform detectors show that this algorithm is useful when data frames are crowded with sources - circumstance where 'median filtering' flatfielding techniques often fail. The algorithm described is robust and efficiently uses information from multiple data frames to determine pixel gain variations, using visible and IR array observations of extended sources.
Hemodynamic assessment of pulmonary hypertension (2011)

There has been significant progress in our understanding of the pathobiology, epidemiology and prognosis of pulmonary vascular disease and, over the past few years, there has been an explosion of clinical therapeutic trials for pulmonary arterial hypertension (PAH). The increasing number of different conditions now associated with PAH and the appearance of new diagnostic techniques have led to a need for a systematic diagnostic approaches and a new disease classification, which has resulted in notable improvements in the quality and efficacy of clinical care. We appreciate traditional resting right heart catheterization techniques (which still remain the gold standard for diagnosing PAH and managing patients on therapy) and look forward to novel invasive techniques (e.g. intravascular ultrasound) that add greatly to our understanding of right ventricle and pulmonary circulation, and for the interpretation of data from clinical trials as well.
Increased intestinal permeability in patients with inflammatory bowel disease. (2004)

Intestinal permeability can be measured by the sugar absorption test. This test is based on determining the ratio of the urinary excretion of a large and a small carbohydrate after oral administration. The aim of this study was to determine which combination of carbohydrates used in the test gives the highest correlation with disease activity in inflammatory bowel disease. 26 patients with Crohn's disease, 21 patients with ulcerative colitis and 27 healthy control subjects were included in the study. The patients with inflammatory bowel disease had either minimal or highly active disease or were in remission. Two disaccharides (lactulose: L, and cellobiose: C) and two smaller carbohydrates (rhamnose:R, and mannitol:M) were given orally and the urinary excretion was measured by high pressure liquid chromatography followed by pulsed amperometric electrochemical detection on a gold electrode. The ratios C/R, L/R, C/M and L/M were used as indicators for intestinal permeability. - There were no side effects of oral sugar administration. All patients tolerated the test well. Lactulose, rhamnose and cellobiose concentrations are easily be measured in the urine whereas mannitol measurement requires the use of an anion exchanger. This produced inconsistent results. Patients with Crohn's disease or with ulcerative colitis had increased permeability indices in comparison to healthy controls, even in remission. The L/R ratio gave a better differentiation between the healthy controls and patients with active disease than the other agents. Changes in disease activity are best reflected by use of cellobiose/rhamnose excretion quotient.
Analysis of error in reconstruction of two-dimensional signals from irregularly spaced samples (1987)

We consider the problem of estimating a band-limited two-dimensional (2-D) signal based on a finite set of irregularly spaced samples. We derive the minimum mean-squared error estimator of the form of a sum of weighted interpolating functions that are identical in shape but are centered at the irregularly spaced sample points, and show that this estimator is identical to the minimum energy band-limited interpolator that has been previously obtained by others. The relation between the mean-squared error and the set of irregularly spaced sampling points is studied using the minimax principle. The maximum of the mean-squared error over a class of signals is minimized by proper choice of the set of sampling points. Three criteria for evaluating the performance of the sampling point set are derived. From a candidate group of sets of irregularly spaced sampling points, these criteria may be used to select that point set which is optimal for recovery over a class of signals.
Exploring alternative treatments for<i>Helicobacter pylori</i>infection (2014)

Helicobacter pylori (H. pylori) is a successful pathogen that can persist in the stomach of an infected person for their entire life. It provokes chronic gastric inflammation that leads to the development of serious gastric diseases such as peptic ulcers, gastric cancer and Mucosa associated lymphoid tissue lymphoma. It is known that these ailments can be avoided if the infection by the bacteria can be prevented or eradicated. Currently, numerous antibiotic-based therapies are available. However, these therapies have several inherent problems, including the appearance of resistance to the antibiotics used and associated adverse effects, the risk of re-infection and the high cost of antibiotic therapy. The delay in developing a vaccine to prevent or eradicate the infection has furthered research into new therapeutic approaches. This review summarises the most relevant recent studies on vaccine development and new treatments using natural resources such as plants, probiotics and nutraceuticals. In addition, novel alternatives based on microorganisms, peptides, polysaccharides, and intragastric violet light irradiation are presented. Alternative therapies have not been effective in eradicating the bacteria but have been shown to maintain low bacterial levels. Nevertheless, some of them are useful in preventing the adverse effects of antibiotics, modulating the immune response, gastroprotection, and the general promotion of health. Therefore, those agents can be used as adjuvants of allopathic anti-H. pylori eradication therapy.
A Micromechanical Parallel-Class Disk-Array Filter (2007)

A method for realizing a high-order on-chip filter response that combines two fourth-order (i.e., two-pole) micro-mechanically-coupled MEMS-based disk-array sub-filters in a parallel configuration has been used to demonstrate a 163-MHz eighth-order (i.e., four-pole) bandpass filter with a 0.16%-bandwidth insertion loss of 2.73 dB, a 20 dB shape factor of only 1.78, and a termination impedance of only 4 kOmega, which is considerably smaller (i.e., better) than that achievable by a parallel combination of single disk resonators. The key to achieving such performance is the use of two capacitively-transduced disk-array composite sub-filters instead of the usual two stand-alone resonators used in previous parallel filter renditions. Here, the use of 275 mum times 360 mum sub-filters, each comprised of coupled radial-contour mode disk arrays, allows a combining of in-phase outputs to substantially raise output currents towards a 50times reduction in motional impedance versus that of a single disk resonator under the same operating conditions. This then lowers the termination impedance required by the overall filter, facilitating the ease with which other components can match to it, and thereby alleviating one of the primary drawbacks of capacitively-transduced micromechanical filters. By utilizing more than 128 disks and mechanical links, the 560 mum x 360 mum filter of this work comprises a true medium-scale integrated (MSI) mechanical circuit on a chip.
Stereoselective Synthesis of Highly Substituted γ-Lactams by the [3+2] Annulation of α-Siloxy Allylic Silanes with Chlorosulfonyl Isocyanate (2006)

[reaction: see text] A stereoselective synthesis of gamma-lactams by the [3+2] annulation of alpha-siloxy allylic silanes with N-chlorosulfonyl isocyanate (ClSO(2)NCO) was developed. The use of these allylic silanes allowed for further diastereoselective substitution of the resultant N,O-acetal to give highly substituted gamma-lactams. Oxidation of the silyl group afforded access to complex beta-hydroxy-gamma-lactams.
Expression of B7.1 in a MUC1‐expressing mouse mammary epithelial tumour cell line inhibits tumorigenicity but does not induce autoimmunity in <i>MUC1</i> transgenic mice (1999)

The MUC1 epithelial mucin, which is overexpressed and aberrantly glycosylated in breast and other carcinomas, is also expressed on the apical surface of most normal glandular epithelial cells. Since clinical trials evaluating the efficacy of MUC1-based vaccines have been initiated in breast cancer patients, it is important to address the question of whether an effective immune response to the cancer associated mucin can be generated without inducing autoimmunity. Since non-classic cytotoxic T lymphocyte (CTL) responses to MUC1 have been reported, it is also relevant to examine the role of costimulatory molecules in the effective presentation of MUC1 based antigens. We have therefore looked at the effect of expressing B7.1 on the tumorigenicity of a MUC1 expressing mammary epithelial cell line (410.4) in a transgenic mouse expressing MUC1 on its normal glandular epithelial tissues. Coexpression of B7.1 with MUC1 in 410. 4 cells resulted in a dramatic inhibition of tumour growth which depended on the activity of CD4+ and CD8+ T cells. The epithelial tissues in the transgenic mice able to reject the B7.1, MUC1-expressing tumours showed no evidence of degeneration and the mice survived their normal life span. The results demonstrate that an immune response to the MUC1 antigen can be induced in MUC1 transgenic mice and that presentation of the antigen, whether directly or by cross-priming, is markedly enhanced by coexpression of B7.1.
Compression Moulding of Polypropylene Foams and Their Properties (2008)

Compression moulding was used to produce polypropylene foams using azodicarbonamide as a chemical blowing agent. The morphology of the foams is reported in terms of cell size, cell density, and skin thickness using 1.5, 2, 2.5 and 3% of blowing agent. The resulting foams were characterized mechanically in terms of tensile and flexural moduli and comparison with mechanical models was made to predict foam performance. In general, mechanical properties, cell density, skin thickness and foam density decreased, while cell size increased with increasing amount of blowing agent. It was also found that simple mechanical models based solely on foam density and skin thickness were not able to correctly predict all the experimental data. For better prediction, foam density profile must be used.
SMQT-based Tone Mapping Operators for High Dynamic Range Images (2013)

In this paper, tone mapping operations based on the nonlinear successive Mean Quantization Transform (SMQT) are proposed in order to convert high dynamic range images to low dynamic range images. A SMQTbased tone mapping applied on the luminance channel is derived as well as a SMQT-based method working directly on all RGB channels. Both methods are compared to other state-of-the-art methods and produce visually similar results. The processing speeds of the SMQT-based methods are discussed and found to be some of the fastest reported on a single CPU. Furthermore, additional improvement regarding the processing speed and its impact on image quality is investigated.
Growth and characterization of direct mid-IR laser materials (Invited Paper) (2005)

Rare earth doped ternary lead salts are being studied for use as mid-IR laser materials. We summarize progress at the Naval Research Labs on the production and evaluation of this important class of solid-state laser.
Heat Transfer to Blood Flow in a Small Tube (2008)

Blood flow in a small tube (30-1000 mum) can be successfully modeled by the two-fluid model. The fully developed, constant heat flux convective heat transfer problem is studied. The velocity and temperature profiles are determined in closed form. Formulas for friction-factor-Reynolds number product, axial temperature gradient, and Nusselt number are found.
Insect-Microbe Mutualism without Vertical Transmission: a Stinkbug Acquires a Beneficial Gut Symbiont from the Environment Every Generation (2007)

The broad-headed bug Riptortus clavatus (Heteroptera: Alydidae) possesses a number of crypts at a posterior midgut region, which house a dense population of a bacterial symbiont belonging to the genus Burkholderia. Although the symbiont is highly prevalent (95 to 100%) in the host populations, the symbiont phylogeny did not reflect the host systematics at all. In order to understand the mechanisms underlying the promiscuous host-symbiont relationship despite the specific and prevalent association, we investigated the transmission mode and the fitness effects of the Burkholderia symbiont in R. clavatus. Inspection of eggs and a series of rearing experiments revealed that the symbiont is not vertically transmitted but is environmentally acquired by nymphal insects. The Burkholderia symbiont was present in the soil of the insect habitat, and a culture strain of the symbiont was successfully isolated from the insect midgut. Rearing experiments by using sterilized soybean bottles demonstrated that the cultured symbiont is able to establish a normal and efficient infection in the host insect, and the symbiont infection significantly improves the host fitness. These results indicated that R. clavatus postnatally acquires symbiont of a beneficial nature from the environment every generation, uncovering a previously unknown pathway through which a highly specific insect-microbe association is maintained. We suggest that the stinkbug-Burkholderia relationship may be regarded as an insect analogue of the well-known symbioses between plants and soil-associated microbes, such as legume-Rhizobium and alder-Frankia relationships, and we discuss the evolutionary relevance of the mutualistic but promiscuous insect-microbe association.