gebhart/patrepeval huggingface dataset:
Thermoplastic interpenetrating polymer networks of a triblock copolymer elastomer and an lonomeric plastic. II. Mechanical behavior (1981)

Abstract Thermoplastic interpenetrating polymer networks, IPN's, are defined as combinations of two physically crosslinked polymers. A styrene‐b‐ethylene‐co‐butylene‐b‐styrene (SEBS) triblock elastomer was combined with an ionomer prepared from a random copolymer of styrene, methacrylic acid, and isoprene (90/10/1 by volume), and subsequently neutralized. Two subclasses of the thermoplastic IPN's were identified. A sequential polymerization method yielded the chemically blended thermoplastic IPN's (CBT IPN's). Melt blending of the separately synthesized polymers produced the mechanically blended thermoplastic IPN's (MBT IPN's). Stress‐strain and Rheovibron characterization revealed that the CBT IPN's exhibited greater tensile strength and higher elongation at break, but lower moduli than the MBT IPN materials of the same overall composition. Analysis of moduli data with the theories of Takayanagi, Davies, Budiansky, and Kerner disclosed more equal dual phase continuity for the MBT IPN's than the CBT IPN's at each composition. The low modulus of the more rubbery CBT IPN compositions was attributed to a decrease in the effective chain end‐to‐end distance between crosslinks in the elastomeric (EB) center block, brought about by the synthetic method.
A new miniaturised multi-axis force/torque sensors based on optoelectronic technology and simply-supported beam (2016)

This paper presents a methodology for the development of a multi-axis force/torque sensor based on optoelectronic technology. The advantages of using this sensing principle are the low manufacturing costs, the simple fabrication, and the immunity to electrical noise. The force/ torque sensor makes use of six optical sensors: each sensor measures the displacement of a reflective surface that moves integrally with a simply-supported beam. The proposed mechanical structure allows for a variety of shapes on the mechanical structure to be easily adaptable to many robot applications. In this paper, we present a five-axis force/torque sensor based on this optoelectronic principle. To measure force/torque components, two identical three-DoF force/torque sensor structures (comprised of three beams) are mounted on top of each other. Photo sensors and mirrors are fixed inside the structure to measure the six beam deflections. In this paper, we describe the sensor structure, design, fabrication, calibration, and verify our sensor development methodology.
Stereoscopic images quality assessment by jointly evaluating image quality and depth perception (2012)

Objective quality evaluation of stereoscopic images is useful in three-dimensional television application, and it is difficult to establish a reasonable relationship between objective evaluation and quality score. In this paper, a new stereoscopic image quality assessment method is proposed. In the method, stereoscopic features are first extracted to describe perceptual attributes of image quality and depth perception by singular value decomposition. Then, the relationship between stereoscopic features and quality score is established by using support vector regression. Finally, the objective evaluation values are tested on the symmetric database. Experimental results show that the proposed is more effective in quantifying image quality, compared with other two relevant quality evaluation metrics.
Domain-Specific Image Analysis for Cervical Neoplasia Detection Based on Conditional Random Fields (2011)

This paper presents a domain-specific automated image analysis framework for the detection of pre-cancerous and cancerous lesions of the uterine cervix. Our proposed framework departs from previous methods in that we include domain-specific diagnostic features in a probabilistic manner using conditional random fields. Likewise, we provide a novel window-based performance assessment scheme for 2D image analysis which addresses the intrinsic problem of image misalignment. Image regions corresponding to different tissue types are indentified for the extraction of domain-specific anatomical features. The unique optical properties of each tissue type and the diagnostic relationships between neighboring regions are incorporated in the proposed conditional random field model. The validity of our method is examined using clinical data from 48 patients, and its diagnostic potential is demonstrated by a performance comparison with expert colposcopy annotations, using histopathology as the ground truth. The proposed automated diagnostic approach can support or potentially replace conventional colposcopy, allow tissue specimen sampling to be performed in a more objective manner, and lower the number of cervical cancer cases in developing countries by providing a cost effective screening solution in low-resource settings.
Quasi-Phasematched Optical Parametric Oscillators in Lithium Niobate Waveguides as Sources of Widely Tunable Infrared Coherent Radiation (1995)

Efficient, low power, compact sources of tunable coherent near and mid-infrared wavelength radiation are necessary for many applications, including communications, spectroscopy, and process monitoring. Nonlinear optical frequency conversion that shifts laser diode outputs to the desired wavelength has attracted significant attention as a means to meet these requirements. Optical parametric oscillators (OPOs) offer near or mid-infrared wavelengths with extremely wide tunability while requiring only a single pump laser. An OPO is a resonant device which divides short-wavelength pump radiation into a pair of longer-wavelength signal and idler waves. Because of the large circulating signal (and sometimes idler) fields, overall energy conversion efficiency is much larger than that of single-pass interactions such as difference frequency generation (DFG). Because parametric gain increases with pump power while cavity losses generally remain fixed, a minimum pump power is required so that round-trip gain exceeds round-trip loss. One current challenge for OPOs is reducing the oscillation threshold to levels attainable with diode lasers.
Replication of <i>Vibrio cholerae</i> classical CTX phage (2017)

The toxigenic classical and El Tor biotype <i>Vibrio cholerae</i> serogroup O1 strains are generated by lysogenization of host-type-specific cholera toxin phages (CTX phages). Experimental evidence of the replication and transmission of an El Tor biotype-specific CTX phage, CTX-1, has explained the evolution of <i>V. cholerae</i> El Tor biotype strains. The generation of classical biotype strains has not been demonstrated in the laboratory, and the classical biotype-specific CTX phage, CTX-cla, is considered to be defective with regard to replication. However, the identification of atypical El Tor strains that contain CTX-cla-like phage, CTX-2, indicates that CTX-cla and CTX-2 replicate and can be transmitted to <i>V. cholerae</i> strains. The replication of CTX-cla and CTX-2 phages and the transduction of El Tor biotype strains by various CTX phages under laboratory conditions are demonstrated in this report. We have established a plasmid-based CTX phage replication system that supports the replication of CTX-1, CTX-cla, CTX-2, and CTX-O139. The replication of CTX-2 from the tandem repeat of lysogenic CTX-2 in Wave 2 El Tor strains is also presented. El Tor biotype strains can be transduced by CTX phages in vitro by introducing a point mutation in <i>toxT</i>, the transcriptional activator of the <i>tcp</i> (toxin coregulated pilus) gene cluster and the cholera toxin gene. This mutation also increases the expression of cholera toxin in El Tor strains in a sample single-phase culture. Our results thus constitute experimental evidence of the genetic mechanism of the evolution of <i>V. cholerae</i>.
Radially variable reflectivity output coupler of novel design for unstable resonators (1987)

An output coupler with radially variable reflectivity, based on a Fabry-Perot interferometer made of two suitable spherical mirrors, is proposed. Application to a pulsed Nd:YAG laser with an unstable resonator has produced diffraction-limited output beams with energy up to 300 mJ.
Immersion Meta-Lenses at Visible Wavelengths for Nanoscale Imaging (2017)

Immersion objectives can focus light into a spot smaller than what is achievable in free space, thereby enhancing the spatial resolution for various applications such as microscopy, spectroscopy, and lithography. Despite the availability of advanced lens polishing techniques, hand-polishing is still required to manufacture the front lens of a high-end immersion objective, which poses major constraints for lens design. This limits the shape of the front lens to spherical. Therefore, several other lenses need to be cascaded to correct for spherical aberration, resulting in significant challenges for miniaturization and adding design complexity for different immersion liquids. Here, by using metasurfaces, we demonstrate liquid immersion meta-lenses free of spherical aberration at various design wavelengths in the visible spectrum. We report water and oil immersion meta-lenses of various numerical apertures (NA) up to 1.1 and show that their measured focal spot sizes are diffraction-limited with Strehl ratios of approximately 0.9 at 532 nm. By integrating the oil immersion meta-lens (NA = 1.1) into a commercial scanning confocal microscope, we achieve an imaging spatial resolution of approximately 200 nm. These meta-lenses can be easily adapted to focus light through multilayers of different refractive indices and mass-produced using modern industrial manufacturing or nanoimprint techniques, leading to cost-effective high-end optics.
Oocydin A, a chlorinated macrocyclic lactone with potent anti- oomycete activity from Serratia marcescens (1999)

A unique chlorinated macrocyclic lactone, termed oocydin A, was isolated from a strain of Serratia marcescens growing as an epiphyte on Rhyncholacis pedicillata, an aquatic plant native to the Carrao river of the Venezuelan-Guyanan region of South America. The lactone has a molecular mass of 470 Da, and contains one atom of chlorine, a carboxyl group and a tetrahydrofuran ring internal to a larger macrocyclic ring. MICs of approximately 0.03 microg ml(-1) were noted for oocydin A against such phytopathogenic oomycetes as Pythium ultimum, Phytophthora parasitica, Phytophthora cinnamomi and Phytophthora citrophora. With regard to the true fungi, oocydin A had either minimal or no effect against certain Fungi Imperfecti (including several pathogens of humans), two ascomycetes and a basidiomycete. Oocydin A may have potential as an antimycotic in agricultural applications and especially for crop protection.
Cell-penetrating peptides derived from Clostridium difficile TcdB2 and a related large clostridial toxin (2017)

<i>Clostridium difficile</i> TcdB (2366 amino acid residues) is an intracellular bacterial toxin that binds to cells and enters the cytosol where it glucosylates small GTPases. In the current study, we examined a putative cell entry region of TcdB (amino acid residues 1753-1851) for short sequences that function as cell-penetrating peptides (CPPs). To screen for TcdB-derived CPPs, a panel of synthetic peptides was tested for the ability to enhance transferrin (Tf) association with cells. Four candidate CPPs were discovered, and further study on one peptide (PepB2) pinpointed an asparagine residue necessary for CPP activity. PepB2 mediated the cell entry of a wide variety of molecules including dextran, streptavidin, microspheres, and lentivirus particles. Of note, this uptake was dramatically reduced in the presence of the Na<sup>+</sup>/H<sup>+</sup> exchange blocker and micropinocytosis inhibitor amiloride, suggesting that PepB2 invokes macropinocytosis. Moreover, we found that PepB2 had more efficient cell-penetrating activity than several other well-known CPPs (TAT, penetratin, Pep-1, and TP10). Finally, Tf assay-based screening of peptides derived from two other large clostridial toxins, TcdA and TcsL, uncovered two new TcdA-derived CPPs. In conclusion, we have identified six CPPs from large clostridial toxins and have demonstrated the ability of PepB2 to promote cell association and entry of several molecules through a putative fluid-phase macropinocytotic mechanism.
Quick-Actuating Closure And Handling System (1991)

Quick-actuating closure and handling system developed for containers, particularly for high-pressure vessels or shells entered frequently. Features simplicity in design and operation, saving of time, monitoring of leakage, and safety. Another significant feature, use of conical surfaces to engage effectively shear blocks in locked position to provide necessary preload and to transmit internal-pressure load directly to pressure vessel. Designed to impart proper radial movement to shear blocks, based on space available for longitudinal travel of screwjacks. Adaptable to many applications; used for such containers as autoclaves, vacuum chambers, and wide variety of specialized vessels requiring frequent entry and closure.
<title>Quantum cryptographic entangling probe implementation</title> (2005)

For a general entangling probe attacking the BB84 protocol in quantum key distrobution, I show that the simplest quantum circuit representing the optimal entangling probe, and yielding the maximum information gain on the pre-privacy-amplified key, consisting of a single CNOT gate in which the control qubit consists of two polarization-basis states of the signal, the target qubit consists of two probe-photon polarization basis states, and the initial state of the probe is set by the error rate induced by the probe. A method is determined for measuring the appropriate correlated state of the probe. Finally, a possible implementation of the entangling probe is described. the device is a simple special-purpose quantum cryptography.
Binary La-Pd oxide catalyst and method of making the catalyst (1993)

A low-cost catalyst is described having high temperature stability and high three-way automotive exhaust gas catalyst activity at such high temperatures, comprising: (a) an outer catalytic coating of binary La-Pd oxide selected from the group consisting of La[sub 2]Pd[sub 2]O[sub 5] and La[sub 4]PdO[sub 7], calcined and supported on a catalyst-supporting substrate, said oxide being present in an amount to provide 15-150 g of Pd per cubic foot of the substrate.
Effects of Intermittent Interleukin‐2 Therapy on Plasma and Tissue Human Immunodeficiency Virus Levels and Quasi‐Species Expression (2000)

To characterize the effects of intermittent interleukin (IL)-2 therapy on human immunodeficiency virus (HIV), 11 patients underwent detailed virological evaluation during a year of IL-2 therapy. Six patients showed a >0.5 log increase in plasma HIV during at least 1 IL-2 cycle, with 2 experiencing an increase in >50% of cycles. Three of the remaining 5 patients had a >0.5 log decrease during at least 1 IL-2 cycle, and the remaining patients exhibited <0.5 log changes. No changes in lymphoid (tonsil) levels of HIV were seen during the year. Quasi-species analysis in a separate cohort demonstrated that the virus induced by IL-2 most commonly resembled pre-IL-2 plasma quasi species. Thus, intermittent IL-2 does not result in sustained increases in either plasma or tissue levels of HIV and does not result in sustained expression of a previously silent quasi species.
Polymerization of <i>n</i>-Butyl Acrylate by Atom Transfer Radical Polymerization. Remarkable Effect of Ethylene Carbonate and Other Solvents (1998)

Atom transfer radical polymerization (ATRP) of n-butyl acrylate with the homogeneous catalyst, CuIBr/4,4‘-di(5-nonyl)-2,2‘-bipyridine (dNbpy), in benzene, afforded well-defined poly(n-butyl acrylate) with predetermined molecular weights and low polydispersities, Mw/Mn = 1.1. The number-average molecular weight, Mn (measured by GPC and MALDI-TOFMS), was close to the theoretical molecular weight, predetermined by DPn = Δ[M]/[I]0. A similar polymerization in benzene using 2,2‘-bipyridine (bpy) as ligand instead of dNbpy displayed poor control, yielding a polymer whose molecular weight was higher than the theoretical value and demonstrating high polydispersity (Mw/Mn = 2.4). Several solvents were subsequently employed for the polymerizations with the CuIBr/bpy catalyst system. Good control of molecular weight and polydispersity were achieved using ethylene carbonate, and in this system the observed rate of polymerization was even faster than in bulk. The rate of polymerization with the CuIBr/bpy catalyst in ethylene carbonate was first order with respect to the catalyst concentration; a reduction in the concentration of the catalyst led to an increase in the polydispersity of the resulting polymer. Polydispersity decreased on addition of CuIIBr2 or by reducing the amount of ethylene carbonate used. The polymerization in ethylene carbonate with CuPF6/bpy catalyst gave results similar to those observed for the CuIBr/bpy catalyst system. The rapid rate of polymerization in ethylene carbonate was attributed to a monomeric structure of the CuIBr/bpy catalyst, as found for CuIPF6.
Optical quality of tilted spherical mirror unstable resonators. Technical report (1979)

A new class of resonators has recently been proposed which has the property of having different magnifications Mx and My in orthogonal directions perpendicular to the propagation direction; the most interesting cases are those with collimated output analagous to conventional confocal unstable resonators. The designs utilize spherical mirrors which are tilted substantially from the mirror normal. The conventional orientation requires the mirror normal to be along (or very nearly parallel to) the propagation direction. Use of spherical mirrors by this new class of resonators eliminates the difficulties of fabricating mirrors with more complex figures, which would otherwise be required to achieve the desired asymmetric magnification. The critical problem of keeping beam-quality degradation (aberrations) due to mirror tilt within acceptable limits has been examined experimentally and analytically. The results confirm the possibility of achieving acceptable small aberrations for large tilt angles (convex mirror tilt as large as 70 deg, corresponding to 140 deg beam deflection) to operation at infrared wavelengths.
Two factors secreted by the goldfish optic nerve induce retinal ganglion cells to regenerate axons in culture (1995)

Unlike mammals, lower vertebrates can regenerate an injured optic nerve and other pathways of the CNS throughout life. We report here that in dissociated cell culture, goldfish retinal ganglion cells regenerate their axons in response to two factors derived from the sheath cells of the optic nerve. Axogenesis factor 1 (AF-1) is a small peptide (700-900 Da) that is inactivated by treatment with proteinase K but heat stable. A second factor, AF-2, is a polypeptide of ca 12 kDa. In the absence of these factors, dissociated retinal cells remained viable in serum-free, defined media for at least a week but showed little outgrowth, as visualized using the vital dye 5,6-carboxyfluorescein diacetate (5,6-CFDA). The addition of AF-1 induced up to 25% of cells in culture to extend processes > 75 microns in length by 6 d; AF-2 had a lesser but highly significant effect. To verify that neurite outgrowth was from retinal ganglion cells per se, we applied the lipophilic dye 4-Di-10-ASP to the optic tectum and allowed it to diffuse up the optic nerve for several days before culturing the retina. A far greater percentage of cells containing the dye showed axonal outgrowth than was observed from the overall cell population, indicating that ganglion cells are selective targets of the factors. The effects of AF-1 or AF-2 were not secondary to enhanced viability, since neither overall cell survival nor the number of retinal ganglion cells remaining in culture after 6 d was affected by the presence of the factors. The activity of AF-1 and AF-2 was not mimicked by several defined factors tested over a broad concentration range, for example, NGF, BDNF, NT-3, CNTF, taurine, retinoic acid, acidic or basic fibroblast growth factors. The concentration of AF-1 is considerably higher in CM than in optic nerve homogenates, suggesting that it is actively secreted; AF-2 has a similar concentration intra- and extracellularly. Insofar as AF-1 and AF-2 derive from cells of the optic nerve and act upon retinal ganglion cells, they are likely to be important in inducing optic nerve regeneration in vivo.
Cell Penetration Properties of a Highly Efficient Mini Maurocalcine Peptide (2013)

Maurocalcine is a highly potent cell-penetrating peptide isolated from the Tunisian scorpion Maurus palmatus. Many cell-penetrating peptide analogues have been derived from the full-length maurocalcine by internal cysteine substitutions and sequence truncation. Herein we have further characterized the cell-penetrating properties of one such peptide, MCaUF1-9, whose sequence matches that of the hydrophobic face of maurocalcine. This peptide shows very favorable cell-penetration efficacy compared to Tat, penetratin or polyarginine. The peptide appears so specialized in cell penetration that it seems hard to improve by site directed mutagenesis. A comparative analysis of the efficacies of similar peptides isolated from other toxin members of the same family leads to the identification of hadrucalcin's hydrophobic face as an even better CPP. Protonation of the histidine residue at position 6 renders the cell penetration of MCaUF1-9 pH-sensitive. Greater cell penetration at acidic pH suggests that MCaUF1-9 can be used to specifically target cancer cells in vivo where tumor masses grow in more acidic environments.
Reduction of timing jitter in a Q-Switched Nd:YAG laser by direct bleaching of a Cr4+:YAG saturable absorber (2009)

A method for optical triggering of a Q-switched Nd:YAG laser by direct bleaching of a Cr:YAG saturable absorber is described. This method involves the bleaching of a thin sheet of the saturable absorber from a direction orthogonal to the lasing axis using a single laser diode bar, where the Cr:YAG transmission increased from a non-bleached value of 47% to a bleached value of 63%. For steady state operation of a passively Q-switched laser (PRF=10 Hz), the pulse-to-pulse timing jitter showed approximately 12X reduction in standard deviation, from 241 nsec for free running operation to 20 nsec with optical triggering.
An Asymptotic Approach to Parallel Equalization of Filter Bank Based Multicarrier Signals (2013)

A novel equalization structure for filter bank based multicarrier (FBMC) based modulations is proposed in this paper. The equalizer architecture is derived by assuming that the number of carriers is asymptotically large, and it consists of multiple parallel stages that are linearly combined on a per-subcarrier basis. The traditional single-tap per-subcarrier equalizer is obtained as a special case of the proposed architecture when the number of stages is fixed to one. An analytical characterization of the output signal to noise plus distortion ratio is provided, which can be used in practice to fix the number of parallel stages of the equalizer in order to obtain a certain performance level at the minimum complexity. Both simulations and analytical predictions indicate that high performance gains can be obtained with respect to more conventional FBMC equalization approaches. Furthermore, the proposed architecture is also shown to present important advantages in terms of computational complexity when compared with classical FBMC equalization architectures.