gebhart/patrepeval huggingface dataset:
CBE grown 1.5 mu m GaInAsP-InP surface emitting lasers (1993)

GaInAsP-InP surface-emitting (SE) lasers have been fabricated using chemical beam epitaxy (CBE) and their lasing characteristics investigated. A threshold current of 2.6 mA was obtained under 77 K CW operation for a device with an improved GaInAsP contact layer having 0.1- mu m thickness and relatively low hole concentration (1x10/sup 19/ cm/sup -3/) to reduce the optical loss. A hybrid mirror consisting of a semiconductor distributed Bragg reflector (DBR) and Si-SiO/sub 2/ multilayers is introduced. Threshold current as low as 1.7 mA was obtained at 77 K CW operation, the lowest values at 77 K for long-wavelength SE lasers ever reported. Near-room-temperature pulsed operation was also obtained for both structures.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Multigigabit transmission through rain in a dual polarization frequency reuse system: an experimental study (1993)

An experimental terrestrial link was set up for the purpose of evaluating very-high-data-rate communications in dual-polarization frequency reuse systems. Possible applications are in the field of satellite communications. Two 3.2-Gb/s signals using staggered quadriphase shift keying (SQPSK) were transmitted on opposite senses of circular polarization over a 7-km path located in Crane rain region D3. Performance degradation of the demodulator as a function of cross-polarization discrimination (XPD) was evaluated and found to closely match simulation predictions. However, the relationship between XPD and rain attenuation was found to be more complex than thought previously, displaying a relatively slowly varying hysteresis effect as well as significant interactions with characteristics of the receive antenna. The latter effect suggests that careful control of antenna characteristics may be required if such high-data-rate techniques are to be employed in space-ground links.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
On the Flexoelectric Effects in Solid Dielectrics: Theories and Applications (2007)

Abstract We propose here a modified phenomenological model for the flexoelectric effects in solid dielectrics. These effects have been investigated from the viewpoint of equilibrium thermodynamics, and the mathematical expressions of their coupling coefficients are given. Finally, the possibilities of fabricating a new kind of flexoelectric piezoelectric composites by exploiting the flexoelectric charge separation mechanism are discussed. Keywords: Flexoelectric effect Acknowledgment The research reported here was sponsored by the Defence Advanced Research Projects Agency (DARPA) under grant No. N00014-05-1-0898.
Galileo Probe Heat Shield Ablation Experiment (1997)

Covers advancements in spacecraft and tactical and strategic missile systems, including subsystem design and application, mission design and analysis, materials and structures, developments in space sciences, space processing and manufacturing, space operations, and applications of space technologies to other fields.
An analytic model for the response of a CZT detector in diagnostic energy dispersive x‐ray spectroscopy (2006)

A CdZnTe detector (CZTD) can be very useful for measuring diagnostic x-ray spectra. The semiconductor detector does, however, exhibit poor hole transport properties and fluorescence generation upon atomic de-excitations. This article describes an analytic model to characterize these two phenomena that occur when a CZTD is exposed to diagnostic x rays. The analytical detector response functions compare well with those obtained via Monte Carlo calculations. The response functions were applied to 50, 80, and 110 kV x-ray spectra. Two 50 kV spectra were measured; one with no filtration and the other with 1.35 mm Al filtration. The unfiltered spectrum was numerically filtered with 1.35 mm of Al in order to see whether the recovered spectrum resembled the filtered spectrum actually measured. A deviation curve was obtained by subtracting one curve from the other on an energy bin by bin basis. The deviation pattern fluctuated around the zero line when corrections were applied to both spectra. Significant deviations from zero towards the lower energies were observed when the uncorrected spectra were used. Beside visual observations, the exposure obtained using the numerically attenuated unfiltered beam was compared to the exposure calculated with the actual filtered beam. The percent differences were 0.8% when corrections were applied and 25% for no corrections. The model can be used to correct diagnostic x-ray spectra measured with a CdZnTe detector.
The effect of silver ions on the respiratory chain of <i>Escherichia coli</i> (1974)

Silver ions inhibited the oxidation of glucose, glycerol, fumarate, succinate, D- and L-lactate, and endogenous substrates by intact cell suspensions of Escherichia coli. Silver ions reacted with the respiratory chain at two levels. The site most sensitive to inhibition was located between the b-cytochromes and cytochrome a 2 . The second level of inhibition was in the NADH and succinate dehydrogenase regions of the respiratory chain, and was situated on the substrate side of the flavin components.
RGD-human serum albumin conjugates as efficient tumor targeting probes (2009)

4 Objectives Cyclic arginine-glycine-aspartate (RGD) peptides and their derivatives have been intensively studied as tumor targeting probes. One major drawback, however, is their short blood circulation half-lives, which greatly compromises their targeting efficacy. Methods Cyclic peptide, c(RGDyK), together with an organic dye (IRDye800 or Cy5.5) were covalently conjugated onto HSA. The conjugates were subjected to in vitro cell staining, in vivo NIRF imaging, ex vivo NIRF imaging and histological studies to evaluate their feasibility as tumor imaging probes. As a control, RAD peptide was also coupled with HSA and labeled with IRDye800 for in vivo imaging. Results The HSA-RGD-IRDye800 exhibited integrin αvβ3-specific binding in cell staining experiment. In vivo NIR fluorescence imaging showed higher tumor accumulation and tumor/background contrast of HSA-RGD-IRDye800 over RGD-IRDye800. The integrin specificity of HSA-RGD-IRDye800 is confirmed by both successful inhibition of tumor uptake in the presence of c(RGDyK) and the inability to accumulate in integrin positive tumors by RAD-HAS-IRDye800. Histological examination revealed initial tumor vascular binding and eventually both tumor vasculature and tumor cell integrin binding in vivo. Conclusions In summary, we successfully developed a RGD-based protein conjugate with prolonged circulation half-life for NIRF imaging of tumor integrin αvβ3 expression. The success of this study may be generalizable for other peptide-based probes to be conjugated with HSA for prolonged tumor contrast and improved pharmacokinetics.
Plant tRNA ligases are multifunctional enzymes that have diverged in sequence and substrate specificity from RNA ligases of other phylogenetic origins (2005)

Pre-tRNA splicing is an essential process in all eukaryotes. It requires the concerted action of an endonuclease to remove the intron and a ligase for joining the resulting tRNA halves as studied best in the yeast Saccharomyces cerevisiae. Here, we report the first characterization of an RNA ligase protein and its gene from a higher eukaryotic organism that is an essential component of the pre-tRNA splicing process. Purification of tRNA ligase from wheat germ by successive column chromatographic steps has identified a protein of 125 kDa by its potentiality to covalently bind AMP, and by its ability to catalyse the ligation of tRNA halves and the circularization of linear introns. Peptide sequences obtained from the purified protein led to the elucidation of the corresponding proteins and their genes in Arabidopsis and Oryza databases. The plant tRNA ligases exhibit no overall sequence homologies to any known RNA ligases, however, they harbour a number of conserved motifs that indicate the presence of three intrinsic enzyme activities: an adenylyltransferase/ligase domain in the N-terminal region, a polynucleotide kinase in the centre and a cyclic phosphodiesterase domain at the C-terminal end. In vitro expression of the recombinant Arabidopsis tRNA ligase and functional analyses revealed all expected individual activities. Plant RNA ligases are active on a variety of substrates in vitro and are capable of inter- and intramolecular RNA joining. Hence, we conclude that their role in vivo might comprise yet unknown essential functions besides their involvement in pre-tRNA splicing.
New soft-switching inverter for high efficiency electronic ballast with simple structure (1991)

A new electronic ballast is proposed for a fluorescent lamp using a high frequency inverter having zero-voltage and zero-current mixed switching poles to regulate the fluorescent lamp light power for high efficiency and long lamp life. The inverter circuit satisfies almost all of the requirements for starting, dimming and high light-output operation of the fluorescent lamp with a simpler scheme compared with the conventional electronic ballasts. Simulations and experiments are carried out for a FL40 fluorescent lamp drive using a 20 kHz operating frequency.
A context pattern induction method for named entity extraction (2006)

We present a novel context pattern induction method for information extraction, specifically named entity extraction. Using this method, we extended several classes of seed entity lists into much larger high-precision lists. Using token membership in these extended lists as additional features, we improved the accuracy of a conditional random field-based named entity tagger. In contrast, features derived from the seed lists decreased extractor accuracy.
Chemical structure of 1-O-(L-erythro-biopterin-2'-yl)-a-glucose isolated from a cyanobacterium Synechococcus sp. PCC 7942 (2001)

Abstract A pteridine glycoside in Synechococcus sp. PCC 7942, the structure of which had been tentatively identified as biopterin-glucoside, was isolated and characterized for its exact chemical structure by 2D-NMR spectroscopy. The determined structure is 1-0-(L-erythro-biopterin-2'-yl)-α-glucose. It is the first report on the occurrence of a biopterin-glucoside having a α-configured sugar directly attached at the pteridine ring. This result also supports that the previously purified UDP-glucose: BH 4 glucosyltransferase from Synechococcus sp. PCC 7942, which catalyzes the synthesis of BH 4 -glucoside from UDP-glucose and BH 4 , is a α-glucosyltransferase.
Semi-supervised boosting using visual similarity learning (2008)

The required amount of labeled training data for object detection and classification is a major drawback of current methods. Combining labeled and unlabeled data via semi-supervised learning holds the promise to ease the tedious and time consuming labeling effort. This paper presents a novel semi-supervised learning method which combines the power of learned similarity functions and classifiers. The approach capable of exploiting both labeled and unlabeled data is formulated in a boosting framework. One classifier (the learned similarity) serves as a prior which is steadily improved via training a second classifier on labeled and unlabeled samples. We demonstrate the approach on challenging computer vision applications. First, we show how we can train a classifier using only a few labeled samples and many unlabeled data. Second, we improve (specialize) a state-of-the-art detector by using labeled and unlabeled data.
In Situ Scanning Tunneling Microscopy of (Bi)sulfate, Oxygen, and Iodine Adlayers Chemisorbed on a Well-Defined Ru(001) Electrode Prepared in a Non-Ultrahigh-Vacuum Environment (2002)

This work shows that it is possible to prepare a well-defined Ru(001) surface by annealing in an airtight quartz cell purged continuously with hydrogen gas. Cyclic voltammograms obtained in 0.1 M hydrofluoric and perchloric acid solutions contain clear redox characteristics, owing to the interfacial events of hydrogen adsorption/desorption and formation/reduction of an oxygen adlayer. High-quality in situ scanning tunneling microscopy (STM) atomic imaging reveals the hexagonal lattice of the Ru(001) substrate in perchloric acid solutions at the onset of hydrogen evolution. Irreversible adsorption of the (bi)sulfate anions from 0.1 M sulfuric acid at −0.1 V (vs Ag/AgCl) renders a highly ordered structure, identified as (√3 × √7)oblique by in situ STM. This arrangement of (bi)sulfate anions is the same as those found at the (111) surfaces of Au, Pt, Rh, Pd, Ir, and Cu electrodes. Potential excursion to 0.4 V results in a well-ordered (2 × 2) oxygen adlayer at the expense of the (√3 × √7)oblique (bi)sulfate structure. Iodine atoms are adsorbed more strongly than the (bi)sulfate and oxygen adlayer species, irrespective of the potential. In situ STM imaging unveils three iodine adlattices, including (√3 × √3)R30°, (5 × √3)rect, and domain wall structures, as the potential is increased from −0.1 to 0.4 V. Oxidation of iodide to iodine atoms occurs at potentials more positive than 0.5 V to produce multiple layers of iodine adatoms at Ru(001).
Person Identification using Skeleton Information from Kinect (2013)

Abstract—In recent past the need for ubiquitous people identification has increased with the proliferation of human-robot interaction systems. In this paper we propose a methodology of recognizing persons from skeleton data using Kinect. First a half gait cycle is detected automatically and then features are calculated on every gait cycle. As part of new features, proposed in this paper, two are related to area of upper and lower body parts and twelve related to the distances between the upper body centroid and the centriods derived from different joints of upper limbs and lower limbs. Feature selection and classification is performed with connectionist system using Adaptive Neural Network (ANN). The recognition accuracy of the individual people using the proposed method is compared with the earlier methods proposed by Arian et. al and Pries et. al. Experimental results indicate that the proposed approach of simultaneous feature selection and classification is having better recognition accuracy compared to the earlier reported ones. Keywords-Person identification; gait recognition; adaptive artificial neural network(ANN); Kinect; connectionist system I.
Immunomagnetic Separation with Mediated Flow Injection Analysis Amperometric Detection of Viable <i>Escherichia coli</i> O157 (1998)

The coupling of an immunological separation (using immunomagnetic beads) with amperometric flow injection analysis detection of viable bacteria is presented. Using a solution containing Escherichia coli O157, the electrochemical response with two different mediators [potassium hexacyanoferrate(III) and 2,6-dichlorophenolindophenol] was evaluated in the FIA system. Antibody-derivatized Dynabeads were used to selectively separate E. coli O157 from a matrix. The kinetics and the capacity parameters regarding the attachment of bacteria to the immunobeads were studied. The immunomagnetic separation was then used in conjunction with electrochemical detection to measure the concentration of viable bacteria. A calibration curve of colony-forming units (cfu) against electrochemical response was obtained. The detection limit for this rapid microbiological method was 10(5) cfu mL-1, and the complete assay was performed in 2 h. Some advantages over ELISA methods are the direct detection of viable cells (and not total bacterial load) and the need for only one antibody (not enzyme-labeled), thus making the assay faster (only one washing step is necessary) and less expensive.
Sharp Toroidal Resonances in Planar Terahertz Metasurfaces (2016)

A toroidal dipole in metasurfaces provides an alternate approach for the excitation of high-Q resonances. In contrast to conventional multipoles, the toroidal dipole interaction strength depends on the time derivative of the surrounding electric field. A characteristic feature of toroidal dipoles is tightly confined loops of oscillating magnetic field that curl around the fictitious arrow of the toroidal dipole vector.
Effect of Some Polyvalent Cations on the Acidogenicity of Dental Plaque in vivo (1980)

The effect of different metal ions on the acidogenicity of dental plaque was investigated. It was found that mouthrinsing with 20 mM solutions of SnF2, ZnCl2, AlCl3 and FeCl3 inhibited the metabolic activity of dental plaque for periods up to several hours, whereas the same concentration of MgCl2 showed no such effect but on the contrary tended to increase the acid-formation potential. Sodium chloride (40 mM) had no measurable effect.
Study on a Surface-Motor Driven Precise Positioning System (1995)

A newly developed precise positioning system incorporating a surface-motor (SFM) drive unit is presented and its advantageous features, operation principles, electromagnetic drive force design, and some experimental results are described. The stage of our “SFM positioning system” is levitated on a base plate by three air bearing pads; being driven by three brushless-type linear DC motors in three degrees of freedom. The guidance and positioning of the stage’s planar motion are achieved via the simultaneous operation of three identical proportional-integral-derivative (PID) servo-control systems, each having a laser-interferometer position feedback loop. The electromagnetically produced drive forces are analyzed by employing magnetic permeability theory, with good correspondence being obtained between calculated and experimental results. Additionally discussed is the closed-loop dynamic behavior, including the motion caused by three axis-interference. Evaluations of experimental tests indicate that a positioning resolution of 10–20 nm and yaw angle accuracy less than ±0.08 µrad are successfully achieved for an x-y travel range of 10 mm.
Potentiation of the immune response in HIV-1+ individuals. (1996)

T cells from HIV-1+ individuals have a defect in mounting an antigen specific response. HIV-1 Tat has been implicated as the causative agent of this immunosuppression. We have previously shown that HIV-1 Tat inhibits antigen specific proliferation of normal T cells in vitro by binding to the accessory molecule CD26, a dipeptidase expressed on the surface of activated T cells. We now demonstrate that the defective in vitro recall antigen response in HIV-1 infected individuals can be restored by the addition of soluble CD26, probably by serving as a decoy receptor for HIV-1 Tat. The restored response is comparable to that of an HIV-1- individual, suggesting that early in HIV infection there is a block in the memory cell response, rather than deletion of these cells.
Effect of Turning Beans and Fermentation Method on the Acidity and Physical Quality of Raw Cocoa Beans (2010)

This study concerns the influence of turning and fermentation method on quality of ra w cocoa . Fermentation trials were conducted in wooden box, plastic box and in heaps with or not turning. Cocoa fermented in boxes during 4 days without stirring presented pH values above 5.0 while cocoa fermented in heaps presented pH 4.92. For fermentation with turnings, beans treated in wooden box were less acidic than beans fermented in plastic box, which recorded pH 4.75. Cocoa issued from all fermentations methods lasted 5 days without mixing presented pH above 5. Cocoa fermented in plastic box with turnings became acidic with pH 4.73 while acidity disappeared in beans fermented in heaps. A similar trend was observed in the titratable acidity of the dried beans. Cocoa fermented during 4 days without turnings presented a high percentage of purple beans nearly 40% whatever the method. Percentages of defective, slaty and mouldy beans were below 4% with or without turnings. Cocoa beans fermented with turnings recorded about 10% of defectives beans whatever the process. Percentage of purple beans decreased to about 12% for cocoa fermented in wooden box. Naturally, percentage of brown beans increased for cocoa fermented both in wooden box and in heaps. All the beans showed no sign insect damages, and negligible levels of internal molding whatever the turning and the methods of fermentation.
The Interdiffusion of Polymers (1990)

In contrast to interdiffusion in simple liquids, interdiffusion of polymeric chains is dominated by their intertanglement and their large size. These properties profoundly reduce both the molecular mobilities and the role of entropy in driving the mixing. The resulting diffusional processes have only recently been studied. Such studies reveal a wide spectrum of behavior ranging from accelerated interdiffusion (for strongly compatible chains) to its suppression below the critical point for phase separation. Effects that are still poorly understood include the initial disposition at interfaces of the chains' ends (through which diffusion proceeds by reptation) and the need for cooperative motion, which can strongly magnify local friction.
Detoxification system for inorganic arsenic: transformation of As2O3 into TMAO by vitamin B12 derivatives and conversion of TMAO into arsenobetaine (2008)

A new two-step synthetic pathway developed for the transformation of arsenic trioxide [iAs(III); As(2)O(3)] into arsenobetaine (AB; Me(3)As(+)CH(2)CO(2)(-)) involves treatment of iAs(III) with native B(12) or biomimetic B(12) in the presence of glutathione (GSH) to give TMAO with a high selectivity and a high conversion rate; subsequent treatment of TMAO with iodoacetic acid in the presence of GSH gives arsenobetaine.
Interaction of hydrophobic polymers with model lipid bilayers (2017)

The interaction of nanoscale synthetic materials with cell membranes is one of the key steps determining nanomaterials' toxicity. Here we use molecular simulations, with atomistic and coarse-grained resolution, to investigate the interaction of three hydrophobic polymers with model lipid membranes. Polymer nanoparticles made of polyethylene (PE), polypropylene (PP) and polystyrene with size up to 7 nm enter easily POPC lipid membranes, localizing to the membrane hydrophobic core. For all three materials, solid polymeric nanoparticles become essentially liquid within the membrane at room temperature. Still, their behavior in the membrane core is not the same: PP and PS disperse in the core of the bilayer, while PE shows a tendency to aggregate. We also examined the interaction of the polymers with heterogeneous membranes, consisting of a ternary lipid mixture exhibiting liquid-ordered/liquid-disordered phase separation. The behavior of the three polymers is markedly different: PP disfavors lipid phase separation, PS stabilizes it, and PE modifies the topology of the phase boundaries and causes cholesterol depletion from the liquid ordered phase. Our results show that different hydrophobic polymers have major effects on the properties of lipid membranes, calling for further investigations on model systems and cell membranes.