gebhart/patrepeval huggingface dataset:
Recombination processes controlling the carrier lifetime in n−4H–SiC epilayers with low Z1/2 concentrations (2010)

The dominant recombination processes controlling the carrier lifetime in n-type 4H–SiC epitaxial layers grown with low concentrations of the Z1/2 defect (the dominant bulk lifetime killer), where Z1/2 no longer determines the lifetime, have been investigated by studying the variation in the carrier lifetime with temperature. The temperature dependent lifetimes were obtained primarily by low-injection photoluminescence decay for several low-Z1/2 epilayers over a wide temperature range. The results were fitted to simulations of the temperature dependent recombination rate, where bulk, surface and interface recombination was considered. No significant contribution from other bulk defects was observed, and upper limits to the bulk recombination rate were found to be consistent with the low Z1/2 concentrations measured in these materials. There was also no significant contribution from carrier capture at the epilayer/substrate interface, which is consistent with behavior expected at low injection for low-doped epilayers grown on n+ substrates. Corresponding high-injection measurements exhibited very different behavior, consistent with the surface/interface under flat-band conditions. Consequently, it is concluded that for low-Z1/2 materials, control of the carrier lifetime has not been transferred from Z1/2 to another bulk defect, but is instead dominated by surface and interface recombination. Simulations suggest that further enhancement of the total lifetime under the high injection conditions of a device structure would require very thick epilayers, effectively passivated surface and interface recombination and a further reduction in the remaining Z1/2 concentrations. The temperature dependence of the low-injection carrier lifetime was also found to provide a method to estimate the surface band bending and the surface defect density.
Data Mining in situ Gene Expression Patterns at Cellular Resolution (2006)

In the post-genomic era, large-scale efforts have begun to characterize the role of gene products. Several of these efforts aim to systematically discover the activity of all /spl sim/20,000 genes throughout functionally complex tissue specimens such as embryo and the mature brain. By applying a subdivision-based deformable model of the brain, we rapidly organize spatial gene expression data into a common coordinate system. Doing this enables powerful queries, comparisons, and associations of the data.
The effect of synbiotics and probiotics on the growth performance, gastrointestinal function and health status of turkeys (2021)

The aim of this study was to evaluate the growth performance, gastrointestinal function and health status of turkeys fed diets supplemented with synbiotic preparations, as compared with commercial probiotic feed additives. The experiment lasted for 15 weeks. The research material comprised 600 female BIG 6 turkeys (6 treatments, 5 replicates, 20 birds per replicate). The turkeys from the control group (I) received a diet without additives. Groups II and III received a basal diet with the addition of probiotic BioPlus 2B or Cylactin at 0.4 g/kg diet, respectively. In groups IV, V and VI turkeys were fed diets with synbiotic preparations S1 (<i>L. reuteri, L. plantarum, L. pentosus, S. cerevisiae</i> + inulin), S2 (<i>L. reuteri, L. plantarum, L. pentosus, S. cerevisiae, L. rhamnosus</i> + inulin) and S3 (<i>L. reuteri, L. plantarum, L. pentosus, S. cerevisiae, L. rhamnosus, L. paracasei</i> + inulin) at 0.5 g/kg diet, respectively. The following parameters were monitored: growth performance, carcass quality, the chemical composition of meat, the structure (length, weight, villus height, crypt depth) and functional parameters (pH, viscosity) of selected segments of the gastrointestinal tract, and the health status of birds (lysozyme, gamma-globulins, ceruloplasmin and total protein). Dietary supplementation with probiotics and synbiotics contributed to an increase in the final body weights of turkeys, a decrease in the feed conversion ratio and an increase in values of the European Production Efficiency Factor (<i>p</i> ≤ 0.05). Synbiotics improved the immune status of birds by increasing serum gamma-globulin levels and decreasing ceruloplasmin activity at 8<sup>th</sup> week of age (<i>p</i> ≤ 0.05). Synbiotics and probiotics also contributed to a decrease in crop and caecal pH (<i>p</i> ≤ 0.05). The analysed additives had no effect on carcass dressing percentage, carcass quality characteristics or the chemical composition of breast muscles. The tested synbiotics as well as commercial probiotics can be valuable feed additives, improving the growth performance and immune status of turkeys.
A comparison between temporal and subband minimum variance adaptive beamforming (2014)

This paper compares the performance between temporal and subband Minimum Variance (MV) beamformers for medical ultrasound imaging. Both adaptive methods provide an optimized set of apodization weights but are implemented in the time and frequency domains respectively. Their performance is evaluated with simulated synthetic aperture data obtained from Field II and is quantified by the Full-Width-Half-Maximum (FWHM), the Peak-Side-Lobe level (PSL) and the contrast level. From a point phantom, a full sequence of 128 emissions with one transducer element transmitting and all 128 elements receiving each time, provides a FWHM of 0.03 mm (0.14λ) for both implementations at a depth of 40 mm. This value is more than 20 times lower than the one achieved by conventional beamforming. The corresponding values of PSL are -58 dB and -63 dB for time and frequency domain MV beamformers, while a value no lower than -50 dB can be obtained from either Boxcar or Hanning weights. Interestingly, a single emission with central element #64 as the transmitting aperture provides results comparable to the full sequence. The values of FWHM are 0.04 mm and 0.03 mm and those of PSL are -42 dB and -46 dB for temporal and subband approaches. From a cyst phantom and for 128 emissions, the contrast level is calculated at -54 dB and -63 dB respectively at the same depth, with the initial shape of the cyst being preserved in contrast to conventional beamforming. The difference between the two adaptive beamformers is less significant in the case of a single emission, with the contrast level being estimated at -42 dB for the time domain and -43 dB for the frequency domain implementation. For the estimation of a single MV weight of a low resolution image formed by a single emission, 0.44 * 109 calculations per second are required for the temporal approach. The same numbers for the subband approach are 0.62 * 109 for the point and 1.33 * 109 for the cyst phantom. The comparison demonstrates similar resolution but slightly lower side-lobes and higher contrast for the subband approach at the expense of increased computation time.
Interleukin-1β (IL-1β), IL-1 receptor antagonist, and TNFα production in whole blood (1992)

The ability of an individual to mount defense responses to infection depend in part on the capacity to produce cytokines such as interleukin 1 (IL-1) and tumor necrosis factor (TNF). The specialized equipment, labor intensity, and sterile practice required for the standard in vitro evaluation of cytokine production can make such evaluation impractical in some clinical situations. We report a method for stimulating whole blood to produce cytokines that can be implemented in laboratories without tissue culture facilities and requires minimal sample preparation. IL-1 beta and TNF alpha production in whole blood samples was stimulated with endotoxin and/or phytohemagglutinin in standard EDTA-containing vacuum collection tubes. After incubation, plasma was removed and frozen for later assay. Comparison of this whole blood method with isolated mononuclear cell cultures indicated a significant correlation for IL-1 beta production (r = 0.746, P = 0.005). This technique also produced the newly described cytokine, IL-1 receptor antagonist. We conclude that the whole blood method is an acceptable alternative to isolated cell culture methods for measuring IL-1 beta in situations that preclude the standard in vitro approach.
Supplemental Methods from Effective Cancer Vaccine Platform Based on Attenuated <i>Salmonella</i> and a Type III Secretion System (2023)

&lt;p&gt;Supplemental Methods&lt;/p&gt;
The Nordic Tweet Stream: A Dynamic Real-Time Monitor Corpus of Big and Rich Language Data. (2018)

This article presents the Nordic Tweet Stream (NTS), a cross-disciplinarycorpus project of computer scientists and a group of sociolinguists interestedin language variability and in the global spread of English. Our research integratestwo types of empirical data: We not only rely on traditional structured corpusdata but also use unstructured data sources that are often big and rich inmetadata, such as Twitter streams. The NTS downloads tweets and associatedmetadata from Denmark, Finland, Iceland, Norway and Sweden. We first introducesome technical aspects in creating a dynamic real-time monitor corpus, andthe following case study illustrates how the corpus could be used as empiricalevidence in sociolinguistic studies focusing on the global spread of English tomultilingual settings. The results show that English is the most frequently usedlanguage, accounting for almost a third. These results can be used to assess howwidespread English use is in the Nordic region and offer a big data perspectivethat complement previous small-scale studies. The future objectives include annotatingthe material, making it available for the scholarly community, and expandingthe geographic scope of the data stream outside Nordic region.
Development of one-cell porcine embryos to the blastocyst stage in simple media. (1991)

Porcine embryos were flushed from mated donors and examined for cleavage stage. One- and two-cell embryos were randomly allotted to one of the five following in vitro treatments: M199 with Earle's salts, a modified Tyrode's medium (TL), TL supplemented with 10 mM N-2-hydroxyethyl-piperazine-N'-2-ethanesulfonic acid (HEPES) (TLH), TLH supplemented with 5.5 mM glucose (TLHG), or TLH supplemented with 5 mM glutamine (TLHGL). The bicarbonate concentration of TLH, TLHG, and TLHGL was 2 mM, compared with the 25 mM concentration in M199 and TL. Embryos in M199 and TL were incubated in 95% air:5% CO2 at 39 degrees C. Those in the remaining three treatments were incubated in air at 39 degrees C. Embryos incubated in TL and M199 did not develop past the four- to eight-cell stage, whereas the proportions of embryos developing to the compact morula or blastocyst stage by d 7 of culture in the other treatments were as follows: TLHG, 49.1%; TLHGL, 59.4%; TLH, 63.5% (P less than .005). These results indicate that porcine embryos can be cultured from the one-cell stage to blastocyst in a simple HEPES-buffered medium in air. The ability of porcine embryos to develop without supplemental CO2 may be an important finding for use in situations in which embryos must be transported for long periods before embryo transfer.
Holographic diffractive optical elements allow improvements in conduction laser welding of steels (2006)

Computer generated holographic elements have been successfully used as a novel beam delivery method in conduction limited laser welding 316L stainless steel using a 1.2kW CO2 laser. An ideal weld zone profile was thermally modelled to produce the desired thermal contours in the substrate. This was then utilised to fabricate a diffractive optical element (DOE), which returned the desired flux distribution specific to this operation. A number of completely bespoke beam irradiance distributions have been produced in this way. When compared to an equivalent Gaussian beam distribution, focussed using conventional lenses, significant improvements in weld quality are seen. Material migration, for example, is considerably reduced, as diffractives afford more control over the thermal gradient on the substrate surface. This means less material is drawn to the outer periphery of the weld, from the viscous melt pool. One of the most noteworthy advantage to using diffractive optics is the huge depth of field they provide, when compared to conventional lenses and Gaussian optics. The equivalent lens focal distance would be 460mm, giving a large depth of field regardless; and the resultant beam is composed of an array of diffracting planes, meaning an ever greater flexibility in usable focal range. The weld microstructures have been investigated using EBSD (Electron Back Scatter Diffraction) and EDS (Energy Dispersive Spectroscopy); and in 316L stainless steel, show substantial differences between Gaussian and diffractive welds. Gaussian beam weld microstructures in 316L stainless steel, tend to have much larger average grain sizes (up to approx. 2500% of substrate); moreover, the grains have a comparably smaller misorientation angle, meaning untreated Gaussian welds would be more susceptible to mechanical failure. The microstructural advantage to using diffractive optics to shape the laser beam are that the grain structure is on average, smaller (up to approx 1500% of substrate) and equiaxed, like that of the substrate, leading to better mechanical properties without the need for heat treatment.
Gamma ray spectroscopy and timing using LSO and PIN photodiodes (1995)

The high density, high light output, and short decay time of LSO (lutetium orthosilicate, Lu/sub 2/SiO/sub 5/:Ce) make it an attractive scintillator for gamma ray spectroscopy. The low cost, small size, high quantum efficiency, and ruggedness of silicon photodiodes make them attractive photodetectors for this same application, although their high noise (compared to a photomultiplier tube) reduces their appeal. In this work we measure the gamma ray energy resolution, timing accuracy, and conversion factor from gamma energy to number of electron-hole pairs produced with a 3/spl times/3/spl times/22 mm/sup 3/ LSO scintillator crystal read out with a 3/spl times/3 mm/sup 2/ silicon PIN photodiode. When the detector is excited with 511 keV photons, a photopeak centered at 1940 e/sup -/ with 149 keV fwhm is observed and a timing signal with 35 ns FWHM jitter is produced. When the detector is excited with 1275 keV photons, a photopeak centered at 4910 e/sup -/ with 149 keV FWHM is observed and a timing signal with 25 ns FWHM jitter is produced. While these performance measures are inferior to those obtained with photomultiplier tubes, they are acceptable for some applications.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Ultrafast Electron Injection:  Implications for a Photoelectrochemical Cell Utilizing an Anthocyanin Dye-Sensitized TiO2Nanocrystalline Electrode (1997)

A photoelectrochemical cell utilizing flavonoid anthocyanin dyes extracted from blackberries, along with colloidal TiO2 powder, is shown to convert sunlight to electrical power at an efficiency of 0.56% under full sun. Fluorescence quenching is observed for the excited state of the TiO2-adsorbed anthocyanin dye, cyanin, and the photocurrent spectrum correlates well with the optical absorption of the cyanin-sensitized TiO2 nanocrystalline film. The incident photon-to-current efficiency of 19% at the peak of the visible absorption band of the dye, the open-circuit voltages of 0.5−0.4 V, and short-circuit photocurrents of 1.5−2.2 mA/cm2 are remarkable for such a simple system and suggest efficient charge carrier injection. The ultrafast excited-state dynamics of cyanin in solution are compared with those of surface-adsorbed cyanin on TiO2 and ZrO2 colloids, as well as complexed with Al(III) ions. A transient absorption signal with a risetime of <100 fs for cyanin-sensitized TiO2 nanoparticles is assigned to electrons injected from the dye to TiO2. This signal is fit to a double-exponential decay with time constants of 0.52 and 67 ps. The 0.52 ps component is due to trapping of conduction band electrons or to fast direct recombination with the dye cation, while the 67 ps decay is attributed to trap state mediated indirect recombination. In contrast, stimulated emission with a 2.6 ps decay time is observed for cyanin in solution, cyanin on ZrO2, and cyanin complexed with Al(III) ions. When compared to the photon-to-current efficiency measured for the solar cell, the efficiency estimated from the injection and recombination rate constants suggests that electron recapture by the redox mediator and light screening mechanisms may limit the efficiency of the cell.
Noise Figure of an Active Antenna Array and Receiver System (2022)

Progress has been made in extending traditional antenna terms to complex phased array receivers, but a satisfactory definition for the noise figure of an active antenna and receiver system has not yet been given. This is particularly so for the case of a complex phased array with electronic gains in each signal path and beams formed using digital signal processing. We provide a simple definition for the active antenna and receiver noise figure, which is consistent with existing active antenna terms. The active antenna noise figure can be measured using the antenna Y-factor technique.
Platelets and Prostaglandins in Coronary Artery Disease (1983)

THE ROLE of platelets in the genesis of atherosclerosis and its manifestations has received considerable attention. Based on the recognition of platelet "hyperactivity" in patients with coronary artery disease, several platelet-suppressive drugs have been used in a large number of patients. The purpose of this article is to review the role of platelets, the mechanisms of platelet activation, and the results of platelet-inhibitory drug trials in patients with coronary artery disease. <h3>PLATELETS AND HEMOSTASIS</h3> Platelets, small disklike cells circulating in the blood, have a primary role in hemostasis. With stress to the endothelium and its subsequent disruption, platelets adhere to the subendothelial collagen. Circulating platelets are attracted to the adhering platelets, resulting in platelet aggregation and formation of a platelet thrombus. In this thrombus, RBCs, WBCs, and other components of blood are incorporated, resulting in an occlusive clot. On activation, platelets also release potent hormones, prostaglandins, polypeptides, and other vasoactive
Stochastic dynamic programming control policies for fuel efficient vehicle following (2013)

Stochastic control policies are developed for fuel-efficient following of a lead vehicle moving at a constant speed. Assuming that a lead vehicle is travelling at a specified speed and that the road grade is modeled stochastically, we solve numerically a Stochastic Dynamic Programming (SDP) problem to determine follower vehicle speed control policies subject to constraints on vehicle following distance. The cost function to which SDP is applied reflects fuel consumption, travel time and includes a penalty for distance constraint violation. A virtual testing environment based on CarSim is used for simulations and fuel economy assessment. We demonstrate the potential for fuel consumption improvements (over 5%) and examine properties of the speed control policy of the follower vehicle, including the emergent `pulse and glide' behavior. The policies do not require preview information of the route and of the road grade thereby providing a potentially simpler alternative to preview-based systems. The results complement our previous results on fuel efficient in traffic driving.
Alkyl Chains of Surface Ligands Affect Polytypism of CdSe Nanocrystals and Play an Important Role in the Synthesis of Anisotropic Nanoheterostructures (2010)

We show that the length of the alkyl chain of surface ligands can shift the equilibrium between the wurtzite and zinc blende polytypes of CdSe nanocrystals. In-situ wide-angle X-ray scattering measurements reveal that short-chain (e.g., propyl) phosphonic acids stabilize CdSe nanocrystals with the zinc blende phase whereas octadecylphosphonic acid stabilize nanocrystals with the wurtzite phase. We also demonstrate how this effect can be used to improve the shape selectivity in the synthesis of anisotropic CdSe/CdS and ZnSe/CdS nanoheterostructures.
Multi-digit Number Recognition from Street View Imagery using Deep Convolutional Neural Networks (2013)

Recognizing arbitrary multi-character text in unconstrained natural photographs is a hard problem. In this paper, we address an equally hard sub-problem in this domain viz. recognizing arbitrary multi-digit numbers from Street View imagery. Traditional approaches to solve this problem typically separate out the localiza-tion, segmentation, and recognition steps. In this paper we propose a unified ap-proach that integrates these three steps via the use of a deep convolutional neu-ral network that operates directly on the image pixels. We employ the DistBe-lief (Dean et al., 2012) implementation of deep neural networks in order to train large, distributed neural networks on high quality images. We find that the per-formance of this approach increases with the depth of the convolutional network, with the best performance occurring in the deepest architecture we trained, with eleven hidden layers. We evaluate this approach on the publicly available SVHN dataset and achieve over 96 % accuracy in recognizing complete street numbers. We show that on a per-digit recognition task, we improve upon the state-of-the-art, achieving 97.84 % accuracy. We also evaluate this approach on an even more challenging dataset generated from Street View imagery containing several tens of millions of street number annotations and achieve over 90 % accuracy. To further explore the applicability of the proposed system to broader text recognition tasks, we apply it to transcribing synthetic distorted text from a popular CAPTCHA ser-vice, reCAPTCHA. reCAPTCHA is one of the most secure reverse turing tests that uses distorted text as one of the cues to distinguish humans from bots. With the proposed approach we report a 99.8 % accuracy on transcribing the hardest cat-egory of reCAPTCHA puzzles. Our evaluations on both tasks, the street number recognition as well as reCAPTCHA puzzle transcription, indicate that at specific operating thresholds, the performance of the proposed system is comparable to, and in some cases exceeds, that of human operators. 1
Particle generation in a chemical vapor deposition/plasma-enhanced chemical vapor deposition interlayer dielectric tool (1998)

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998.
Design of Sulfonium Compounds as a Photo-acid Generator (2007)

Triarylsulfonium compounds with relatively higher reduction potentials by introduction of electron withdrawing groups and expansion of π-electron resonance were newly designed and synthesized. These sulfonium compounds exhibited high acid generation efficiency, which were cationic polymerization ability, by electron transfer induced photo-sensitization with dyes. The thermal stability of these compounds was investigated from a practical standpoint, and also the influence of the stability by varying the counter anion was examined. Further, these sulfonium compounds were applied to radical promoted cationic polymerization and infrared-dye induced photo-sensitization.
ChemInform Abstract: An Efficient Synthesis of Analogues of Unsymmetrical Archaeal Tetraether Glycolipids. (1998)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
THE PHYSIOLOGIC SUBTYPING OF SCHIZOPHRENIA: GENETIC APPROACHES (1992)

BLACKWOOD, D. H.R.*; MUIR, W. J.*; GLABUS, M.**; WALKER, M.*; ROXBOROUGH, H.*; SHARP, C.*; DUNAN, J.*Author Information