gebhart/patrepeval huggingface dataset:
Experimental Study of the Nonlinear Dynamics of an Actively Q-Switched Ytterbium-Doped Fiber Laser (2012)

In this paper, a comprehensive experimental study of the dynamics of an actively Q-switched Yb-doped GTWave-based fiber laser is presented. It is shown that the appearance of the Q-switching regime in the laser is sensitive to both the repetition rate and the temporal width of the transparency window of an acousto-optical Q-switch modulator placed in the cavity. It is also shown that, at low repetition rates, a peculiar self-Q-switch regime induced by stimulated Brillouin scattering is observed in the laser, which interferes stochastically with the regular (true) active Q-switching mode. While increasing the Q-modulator repetition rate, the self-Q-switch pulsing steadily vanishes but the true Q-switching remains. The latter, however, becomes strongly subjected, while further increasing the Q-switch repetition rate, by the nonlinear laser dynamics effects. That is, the laser is allowed to operate at certain subharmonics of the repetition rate or in some specific regimes that occur at laser transients from one attractor to another. These transient regimes are characterized by alternating between pulse amplitude and energy, and pulse spacing or chaos, which is strongly influenced by the adjacent attractors' properties.
RANDGAN: Randomized Generative Adversarial Network for Detection of\n COVID-19 in Chest X-ray (2020)

COVID-19 spread across the globe at an immense rate has left healthcare\nsystems incapacitated to diagnose and test patients at the needed rate. Studies\nhave shown promising results for detection of COVID-19 from viral bacterial\npneumonia in chest X-rays. Automation of COVID-19 testing using medical images\ncan speed up the testing process of patients where health care systems lack\nsufficient numbers of the reverse-transcription polymerase chain reaction\n(RT-PCR) tests. Supervised deep learning models such as convolutional neural\nnetworks (CNN) need enough labeled data for all classes to correctly learn the\ntask of detection. Gathering labeled data is a cumbersome task and requires\ntime and resources which could further strain health care systems and\nradiologists at the early stages of a pandemic such as COVID-19. In this study,\nwe propose a randomized generative adversarial network (RANDGAN) that detects\nimages of an unknown class (COVID-19) from known and labelled classes (Normal\nand Viral Pneumonia) without the need for labels and training data from the\nunknown class of images (COVID-19). We used the largest publicly available\nCOVID-19 chest X-ray dataset, COVIDx, which is comprised of Normal, Pneumonia,\nand COVID-19 images from multiple public databases. In this work, we use\ntransfer learning to segment the lungs in the COVIDx dataset. Next, we show why\nsegmentation of the region of interest (lungs) is vital to correctly learn the\ntask of classification, specifically in datasets that contain images from\ndifferent resources as it is the case for the COVIDx dataset. Finally, we show\nimproved results in detection of COVID-19 cases using our generative model\n(RANDGAN) compared to conventional generative adversarial networks (GANs) for\nanomaly detection in medical images, improving the area under the ROC curve\nfrom 0.71 to 0.77.\n
Fate of Asphaltenes During Hydroprocessing of Heavy Petroleum Residues (2020)

Formation of coke like sediments or particulates is a serious problem in the hydroprocessing of heavy residues for high conversion. The sediments can cause both operability problems and rapid catalyst deactivation. The macromolecules of the heavy feedstocks such as asphaltenes are believed to contribute significantly to sediment formation and coke deposition. As part of an extensive research program on the factors which influence sludge or solids formation during residue hydroprocessing, we have examined the nature of changes that take place in the characteristics of the asphaltenic fraction of Kuwait vacuum residue under different operating conditions. The studies revealed that sediment formation is the result of reduction in solubilization efficiency of asphaltenes in the product medium compared with feedstock. Molecular size distribution of the product asphaltenes showed that operating at high temperatures enhanced depolymerization and fragmentation of asphaltenes to low molecular weight materials. A portion of the low molecular weight asphaltene fragments with relatively low H/C ratio resisted further cracking even at high temperatures and led to the formation of coke like sediments. Large pore catalysts were observed to reduce the problem of sediments formation. The role of catalyst pore size on asphaltenes conversion is discussed.160
Co-registration of articulographic and real-time magnetic resonance imaging data for multimodal analysis of rapid speech (2012)

We propose a method for co-registrating speech articulatory/acoustic data from two modalities that provide complementary advantages. Electromagnetic Articulography (EMA) provides high temporal resolution (100 samples/second in WAVE system) and flesh-point tracking, while real-time Magnetic Resonance Imaging, rtMRI, (23 frames/second) offers a complete midsagittal view of the vocal tract, including articulated structures and the articulatory environment. Co-registration was achieved through iterative alignment in the acoustic and articulatory domains. Acoustic signals were aligned temporally using Dynamic Time Warping, while articulatory signals were aligned variously by minimization of mean total error between articulatometry data and estimated corresponding flesh points and by using mutual information derived from articulatory parameters for each sentence. We demonstrate our method on a subset of the TIMIT corpus elicited from a male and a female speaker of American English, and illustrate the benefits of co-registered multi-modal data in the study of liquid and fricative consonant production in rapid speech. [Supported by NIH and NSF grants.]
H.264/AVC stream replacement technique for video watermarking (2008)

This paper describes a method for applying a watermark directly to an entropy coded H.264/AVC stream. This method can be applied when the stream, or at least the I-frames, is entropy coded with CAVLC. Most of the hard work goes into building an embedding table during an analysis stage. This table identifies small segments of data in the encoded stream that will be replaced. The table also provides alternative values for each segment. The embedding process involves replacing each identified segment with one of the alternative values from the table. The choice of alternative is informed by the payload to be embedded. The resulting bitstream is guaranteed to be compliant with the H.264/AVC standard.
On discrete alphabets for the two-user Gaussian interference channel with one receiver lacking knowledge of the interfering codebook (2014)

In multi-user information theory it is often assumed that every node in the network possesses all codebooks used in the network. This assumption is however impractical in distributed ad-hoc and cognitive networks. This work considers the two-user Gaussian Interference Channel with one Oblivious Receiver (G-IC-OR), i.e., one receiver lacks knowledge of the interfering cookbook while the other receiver knows both codebooks. We ask whether, and if so how much, the channel capacity of the G-IC-OR is reduced compared to that of the classical G-IC where both receivers know all codebooks. Intuitively, the oblivious receiver should not be able to jointly decode its intended message along with the unintended interfering message whose codebook is unavailable. We demonstrate that in strong and very strong interference, where joint decoding is capacity achieving for the classical G-IC, lack of codebook knowledge does not reduce performance in terms of generalized degrees of freedom (gDoF). Moreover, we show that the sum-capacity of the symmetric G-IC-OR is to within O(log(log(SNR))) of that of the classical G-IC. The key novelty of the proposed achievable scheme is the use of a discrete input alphabet for the non-oblivious transmitter, whose cardinality is appropriately chosen as a function of SNR.
Surfactants from fatty esters of polyalkoxylated polyol glycosides (1973)

Abstract The glycoside raw materials used to prepare the surfactants were mixtures produced directly from low cost starch and the polyols by transglycosidation. After alkoxylation with ethylene oxide and propylene oxide, the glycosides were transesterified by the methyl esters of various fatty acids to yield the final products. Monolaurates of the polyalkoxylated glycosides containing a combination of 8 mol ethylene oxide and 4 mol propylene oxide per mole of glycoside showed detergency in an alkaline formulation comparable to two commercial detergents. An advantage in this application is the potential for complete biodegradation because of the fatty ester carbohydrate structures. The two monolaurates of glycerol glycoside polyethers containing 4.8 and 8 mol propylene oxide, in particular, produced oil‐inwater emulsions of high stability.
3,3’’-Bis(saccharin-6-ylmethyl)-1,1’:3’,1’’-terphenyl – Precursor of A New Tetradendate Bis-bridging Ligand (2012)

The title compound (H 2 tpsac) was synthesized from 6-bromosaccharin and 3,3’’-bis(bromomethyl)- m-terphenyl. The ability of tpsac to serve as a tetradentate bis-bridging ligand was demonstrated by the formation of the dinuclear ruthenium(I,I) complexes [Ru 2 (CO) 5 (μ,μ-tpsac)] 2 , [Ru 2 (CO) 4 (μ,μ-tpsac)] n , [Ru 2 (CO) 4 (PPh 3 ) 2 (μ,μ-tpsac)], and [Ru 2 (CO) 5 (PPh 3 )(μ,μ-tpsac)]. An X-ray crystal structure analysis of [Ru 2 (CO) 4 (PPh 3 ) 2 (μ,μ-tpsac)] showed the head-to-tail (or 1,1) arrangement of the two saccharinate coordination sites.
TUG USAGE WITH IMPAIRED MANEUVERABILITY (1983)

Abstract : The investigations described in this report represent a second in a series of investigations planned at CAORF to study the effectiveness of tugs in restricted waterways and the variability in pilot operating procedures. One part of the previous study was concerned with the effectiveness of tugs in assisting an 80,000 DWT and a 250,000 DWT tanker following a complete failure with rudder amidships and a loss of engine power simultaneously, and just before entering a 45 degrees turn. Because such a combined failure is extremely severe and has a low probability of occurring, the present study aimed at more realistic failure conditions on a rudder failure (amidships), or no failure at all could occur at any of the four locations prior to the turn, or four locations in the turn. In addition, the failure could be followed by a recovery in a realistic time period, or no recovery at all. Twelve subjects took part in the experiment; six had tugs available and six had no tugs. They performed a total of 12 runs apiece, and experienced engine and rudder failures with and without recovery and at various locations in an order consistent with the statistical experiment design. The data from the experiment were examined qualitatively and selected performance measures were subjected to statistical analyses. Based on these practically useful observations, conclusions were drawn from both the non-failure and failure runs regarding pilot procedures with helm, engine and tug power in relationship to the type and location of the failure. (Author)
Increased photoconductivity lifetimes in GaAs nanowires via n-type and p-type shell doping (2016)

Reliable doping in GaAs nanowires is essential for the development of novel optoelectronic devices. Previously, GaAs nanowires have been shown to exhibit extremely short photoconductivity lifetimes of a few picoseconds due to their high surface recombination velocity, which is detrimental for nanowire devices, such as solar cells and nanowire lasers. Here, we show that, by exploiting engineered band-bending via selective doping, this parasitic surface recombination can be reduced. We utilise non-contact time-resolved terahertz spectroscopy to characterise the doping efficiency in n-type and p-type doped GaAs nanowire <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> and show high carrier concentrations of the order of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">18</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> . The carrier lifetimes were increased by an order of magnitude from 0.13ns for undoped to 3.8ns and 2.5ns for n-doped and p-doped GaAs nanowires respectively; showing that surface recombination is greatly suppressed as a result of shell doping. We also present a novel effect of p-doping in GaAs nanowires: a rapid decay in photoconductivity within 25ps after photoexcitation. This fast decay is attributed to rapid electron trapping at the nanowire surface due to doping related band bending. Thus, we demonstrate the advantages of selective doping for enhancement of desirable transport properties in GaAs nanowires, as well as highlighting terahertz spectroscopy as a reliable technique for characterising doped GaAs nanowires <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> .
Reversible photopadlocking on double-stranded DNA (2007)

We describe a highly efficient method for reversible photocircularization of oligonucleotide (ODN) on a double-stranded DNA template: 5-carboxyvinyl-2'-deoxyuridine-containing ODN was reversibly circularized around the target sequence of the double-stranded plasmid DNA resulting in formation of a catenated plasmid.
The potential role of lycopene for human health. (1997)

Lycopene is one of the major carotenoids in Western diets and is found almost exclusively in tomatoes and tomato products. It accounts for about 50% of carotenoids in human serum. Among the common dietary carotenoids lycopene has the highest singlet oxygen quenching capacity in vitro. Other outstanding features are its high concentration in testes, adrenal gland and prostate. In contrast to other carotenoids its serum values are not regularly reduced by smoking or alcohol consumption but by increasing age. Remarkable inverse relationships between lycopene intake or serum values and risk have been observed in particular for cancers of the prostate, pancreas and to a certain extent of the stomach. In some of the studies lycopene was the only carotenoid associated with risk reduction. Its role in cancer risk reduction still needs to be clarified. Patients with HIV infection, inflammatory diseases and hyperlipidemia with and without lipid lowering treatment may have depleted lycopene serum concentrations. Before embarking on large-scale human trials the distribution of lycopene and its biological functions need to be further evaluated.
An Investigation of Friction and Wear Behaviors of Polyimide/Attapulgite Hybrid Materials (2005)

Abstract Summary: PI/AT hybrid materials were prepared by blending of poly(amic acid) and purified AT as a type of fibrillar clays. The friction and wear behaviors of the PI hybrids were evaluated on a ball‐on‐disc wear tester. The particle size of AT in the hybrid containing 5 wt.‐% AT was about 10–100 nm in diameter and 100–1 000 nm in length. Tensile tests on the PI hybrids showed that the strength and the toughness of PI/AT hybrid materials were improved simultaneously when the content of AT was less than 5 wt.‐%. The friction coefficient and wear rate of the PI hybrids first decreased and then increased with increasing content of AT. The wear rate of the hybrid containing 3 wt.‐% AT was more than 6 times lower than that of pure PI. SEM examination of worn surfaces showed that type of wear changed from adhesive wear of pure PI into abrasive wear of the PI hybrids with adding AT to PI matrix. Debris analysis suggested that AT as filler inside the PI matrix could prevent the formation of bigger debris and a chemical reaction that occurred during the friction process of pure PI but not in the hybrids. A plot of the calculated wear rate versus filler content. magnified image A plot of the calculated wear rate versus filler content.
Interplay of electronic reconstructions, surface oxygen vacancies, and lattice distortions in insulator-metal transition ofLaAlO3/SrTiO3 (2015)

The mechanism responsible for the extraordinary interface conductivity of ${\mathrm{LaAlO}}_{3}$ on ${\mathrm{SrTiO}}_{3}$ and its insulator-metal transition remains controversial. Here, using density functional theory calculations, we establish a comprehensive and coherent picture that the interplay of electronic reconstructions, lattice distortions, and surface oxygen vacancies fully compensates the polarization potential divergence in ${\mathrm{LaAlO}}_{3}/{\mathrm{SrTiO}}_{3}$, explaining naturally the experimental observations under different conditions. While lattice distortions and a charge redistribution between LaO and ${\mathrm{AlO}}_{2}$ sublayers play a dominant role in the insulating state, a spontaneous appearance of 1/4 oxygen vacancies per ${\mathrm{AlO}}_{2}$ sublayer at the ${\mathrm{LaAlO}}_{3}$ surface accompanied by $0.5{e}^{\ensuremath{-}}$ charge transfer into the interface is responsible for interface conductivity and the discontinuous transition in ${\mathrm{LaAlO}}_{3}/{\mathrm{SrTiO}}_{3}$. Our model also explains properties of ${\mathrm{LaAlO}}_{3}/{\mathrm{SrTiO}}_{3}$ prepared with different growth conditions.
Efficient Gene Marking with a Clinical Gammaretrovirus Vector Expressing MGMTP140K in Baboons and Macaques (2008)

Abstract Using gene therapy to protect hematopoietic stem cells (HSC) from alkylating agents used in the treatment of malignant disease is an attractive strategy to alleviate prolonged neutropenia and thrombocytopenia that is dose-limiting. Both adult and pediatric patients with glioblastomas urgently need improved therapeutic strategies since even with aggressive treatment the median survival after diagnosis is approximately 12 months. Chemotherapy with the nitrosourea BCNU, the methylating agents procarbazine or temozolomide, and other alkylating agents is effective and can prolong survival but the therapeutic benefit is attenuated due to hematopoietic toxicity which limits dose-escalation of these drugs. We have previously demonstrated in the dog and non-human primate model efficient gene marking, in vivo selection and chemoprotection from temozolomide and BCNU following transplantation with MGMTP140K gene-modified cells. Thus, we wanted to explore the efficacy of autologous transplantation in macaques and baboons using cells gene-modified with an MLV-based gammaretrovirus vector developed for a pending clinical trial. This retroviral vector contains a myeloproliferative sarcoma virus LTR, negative control region deleted, dl587rev primer binding site (MND) vector backbone, which expresses MGMTP140K from the 5′ LTR promoter, and is pseudotyped with the gibbon ape leukemia virus (GALV) envelope produced from Phoenix-GALV packaging cells (PhGALV-MND.GRS.P140K c38). Following transduction the gene marking in pre-infusion colony forming units (CFUs) was 74.3% and 69.8% in the macaque and baboon respectively as determined by CFU-PCR. Intracellular MGMT-staining of cultured baboon cells 4 (76.4%) and 11 (89.9%) days after transduction confirmed high gene transfer levels. Both animals recovered neutrophil and platelet levels within expected time frames relative to historical controls and the average provirus copy number determined by real-time PCR approximately one month after transplantation was 0.14 and 0.72 in the macaque and baboon respectively. Retrovirus integration site analysis in the macaque 90 days after transplantation, and before chemotherapy, confirmed polyclonal hematopoietic reconstitution. There was no indication of progression to a pre-leukemic state. The macaque has been treated twice with O6-benzylguanine (O6BG) and BCNU and the gene marking has stably increased approximately 2.5-fold. Aside from transient elevated liver enzymes following O6BG/BCNU treatment no additional extra-hematopoietic toxicity has been observed. In summary, we have been able to achieve efficient polyclonal gene marking with MGMTP140K gene-modified cells using a vector designed for clinical application in both macaques and baboons and have preliminary evidence of in vivo selection in the macaque. We believe that these large animal studies closely reflect a clinical setting and will help to further improve clinical HSC gene therapy.
Effect of a Novel Catechol Copolymer on Cuticle Sclerotization by the American Cockroach (1987)

A new biologically active copolymer containing catechol and succinic acid has been synthesized. This polymer is highly soluble in water and stable at neutral (physiological) pH. An injection of the copolymer into the haemocoel of American cockroaches was lethal. Newly-ecdysed (molted) cockroaches could tolerate only 0.6 mg while interecdysial animals died after injection of 1 mg. The copolymer contains catechol with a free beta carbon which is similar in structure to the natural cuticle sclerotization (hardening) agents. Experiments show that the copolymer appears to bind cuticle protein precursors which could be related to the lethal effect of this agent.
Mitigating Anisotropic Changes in Classical Layered Oxide Materials by Controlled Twin Boundary Defects for Long Cycle Life Li-Ion Batteries (2022)

The classical layered NMC oxides LiNi<sub>x</sub>Mn<sub>y</sub>Co</sub>1–x–y</sub>O<sub>2</sub> (0 < (x,y) < 1) are promising high energy density cathodes for Li-ion batteries. However, their inherent structure instability at the highly delithiated state causes capacity degradation as cycling proceeds. Here, we report a mitigating strategy for addressing the capacity decay problem in multiple classical NMC materials through the design of controlled twin boundary defects. The radially aligned twin boundary defects are engineered in nanosized NMC cathodes through polyol synthesis. The crystallographic orientation of each subgrain rotates across the twin boundaries, and the particles have maximum exposure to the electrolyte with the (003) planes (which are more stable than other planes). Increased cation disorder and the formation of rocksalt-like phase are consistently observed along the twin boundaries through scanning transmission electron microscopy (STEM), acting as a rigid framework that mitigates anisotropic changes in NMC during cycling. Operando X-ray diffraction confirms this hypothesis as the degree of anisotropic changes is minimized in NMC with twin boundaries. The synthesized NMC materials with twin boundary defects exhibits enhanced electrochemical performance compared to the corresponding microsized materials with identical composition. The twin boundary defects engineering in NMC structure can effectively suppress the phase transformation and material degradation, serving as a novel and universal approach in designing stable intercalation compounds for high voltage long-cycle life Li-ion batteries.