gebhart/patrepeval huggingface dataset:
Depth‐consistent P‐P and P‐S seismic image via joint velocity inversion (2001)

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2001Depth‐consistent P‐P and P‐S seismic image via joint velocity inversionAuthors: Yaohui ZhangLong Don PhamFernando NevesYaohui ZhangPGS Seres Division, 738 Highway 6 South, Suite 300, Houston, Texas 77079, Long Don PhamPGS Seres Division, 738 Highway 6 South, Suite 300, Houston, Texas 77079, and Fernando NevesPGS Seres Division, 738 Highway 6 South, Suite 300, Houston, Texas 77079https://doi.org/10.1190/1.1816766 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Permalink: https://doi.org/10.1190/1.1816766FiguresReferencesRelatedDetails SEG Technical Program Expanded Abstracts 2001ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2001 Pages: 2135 publication data© 2001 Copyright © 2001 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished: 03 Jan 2005 CITATION INFORMATION Yaohui Zhang, Long Don Pham, and Fernando Neves, (2001), "Depth‐consistent P‐P and P‐S seismic image via joint velocity inversion," SEG Technical Program Expanded Abstracts : 841-844. https://doi.org/10.1190/1.1816766 Plain-Language Summary PDF DownloadLoading ...
PET imaging of brain acetylcholinesterase using [<sup>11</sup>C]CP‐126,998, a brain selective enzyme inhibitor (2002)

PET and [(11)C]CP-126,998, an N-benzylpiperidinebenzisoxazole, were used to image brain acetylcholinesterase (AChE) distribution in healthy controls before and after administration of 5 mg donepezil p.o., a reversible AChE inhibitor. Logan plots were used to compute distribution volumes (V(T)). The V(T) of [(11)C]CP-126,998 was highest in the basal ganglia and cerebellum and lowest in the cerebral cortex, thalamus, amygdala, and hippocampus. The regional V(T) values correlated well with AChE concentration measured in vitro. Donepezil, given 4 h before PET scanning, induced a substantial inhibition of [(11)C]CP-126,998 binding (43-62%) in all brain regions when compared to the baseline PET study. The results of this study indicate that PET imaging of [(11)C]CP-126,998 may be useful in quantifying the distribution of regional brain AChE. This new PET radiotracer may potentially be employed in the diagnosis and treatment of patients with disorders of cholinergic neurotransmission, such as Alzheimer's disease.
A practical method for numerical evaluation of solutions of partial differential equations of the heat-conduction type (1947)

This paper is concerned with methods of evaluating numerical solutions of the non-linear partial differential equation where subject to the boundary conditions A, k, q are known constants. Equation (1) is of the type which arises in problems of heat flow when there is an internal generation of heat within the medium; if the heat is due to a chemical reaction proceeding at each point at a rate depending upon the local temperature, the rate of heat generation is often defined by an equation such as (2).
Attentive motion sensor for mobile robotic applications (2011)

We present a compact vision sensor comprising a one-dimensional array of adaptive photo-receptors, spatio temporal feature extraction circuits, feature normalization circuits, and an attentional readout circuit that selects the most salient region in the feature map. The sensor comprises also digital input and output circuits for directly interfacing it to digital processing units, making it an ideal device for mobile robotic applications. We describe the sensor architecture and present experimental results measured from the fabricated chip. As we identified unexpected results from one of the computational stages, we compare the measured responses to circuit simulations and propose improvements for new revisions of the chip.
Enhanced resistive switching effect in Ag nanoparticle embedded BaTiO3 thin films (2013)

Ag nanoparticle (NP) embedded BaTiO3 (BTO) thin films on SrRuO3-coated SrTiO3 (STO) substrates are prepared by the integrated nanocluster beam deposition and laser-molecular beam epitaxy. Enhanced resistive switching, up to an ON/OFF ration of 104, has been achieved at low switching voltage (less than 1 V) without a forming voltage. These characteristics make such nanocomposite film very promising for application of low voltage non-volatile random access memory. The enhanced resistive switching effect may be attributed to the charge storage effect of the Ag nanoparticles and easy formation of Ag filament inside the BTO film.
Retro-Inverso Carbohydrate Mimetic Peptides with Annexin1-Binding Selectivity, Are Stable In Vivo, and Target Tumor Vasculature (2013)

Previous research suggests that carbohydrate mimetic peptide IF7 (IFLLWQR) has an excellent targeting property to annexin1 (Anxa1), a specific marker on the tumor endothelium. However, IF7 is susceptible to proteolysis and has a poor stability in vivo. We prepared a D-amino acid, reverse sequence peptide of IF7, designated RIF7, to confer protease resistance while retaining bioactivity. Experimental results indicate that RIF7 had significantly increased stability and an increased receptor binding affinity than IF7, and this new moiety may represent a clinically relevant vehicle for anticancer drugs.
Bacteriophage therapy: a potential solution for the antibiotic resistance crisis (2014)

The emergence of multiple drug-resistant bacteria has prompted interest in alternatives to conventional antimicrobials. One of the possible replacement options for antibiotics is the use of bacteriophages as antimicrobial agents. Phage therapy is an important alternative to antibiotics in the current era of drug-resistant pathogens. Bacteriophages have played an important role in the expansion of molecular biology and have been used as antibacterial agents since 1966. In this review, we describe a brief history of bacteriophages and clinical studies on their use in bacterial disease prophylaxis and therapy. We discuss the advantages and disadvantages of bacteriophages as therapeutic agents in this regard.
Efficient recursive algorithms for detection of abrupt changes in signals and control systems (1999)

This paper addresses a number of open problems concerning the generalized likelihood ratio (GLR) rules for online detection of faults and parameter changes in control systems. It is shown that with an appropriate choice of the threshold and window size, these GLR rules are asymptotically optimal. The rules are also extended to non-likelihood statistics that are widely used in monitoring adaptive algorithms for system identification and control by establishing Gaussian approximations to these statistics when the window size is chosen suitably. Recursive algorithms are developed for practical implementation of the procedure, and importance sampling techniques are introduced for determining the threshold of the rule to satisfy prescribed bounds on the false alarm rate.
Analysis of the Nucleus-Encoded and Chloroplast-Targeted Rieske Protein by Classic and Site-Directed Mutagenesis of Chlamydomonas (1999)

Three mutants of the alga Chlamydomonas reinhardtii affected in the nuclear PETC gene encoding the Rieske iron-sulfur protein 2Fe-2S subunit of the chloroplast cytochrome b(6)f complex have been characterized. One has a stable deletion that eliminates the protein; two others carry substitutions Y87D and W163R that result in low accumulation of the protein. Attenuated expression of the stromal protease ClpP increases accumulation and assembly into b(6)f complexes of the Y87D and W163R mutant Rieske proteins in quantities sufficient for analysis. Electron-transfer kinetics of these complexes were 10- to 20-fold slower than those for the wild type. The deletion mutant was used as a recipient for site-directed mutant petC alleles. Six glycine residues were replaced by alanine residues (6G6A) in the flexible hinge that is critical for domain movement; substitutions were created near the 2Fe-2S cluster (S128 and W163); and seven C-terminal residues were deleted (G171och). Although the 6G6A and G171och mutations affect highly conserved segments in the chloroplast Rieske protein, photosynthesis in the mutants was similar to that of the wild type. These results establish the basis for mutational analysis of the nuclear-encoded and chloroplast-targeted Rieske protein of photosynthesis.
<i>In situ</i> imaging and spectroscopy of single-wall carbon nanotube synthesis by laser vaporization (2000)

The synthesis of single-wall carbon nanotubes by Nd:YAG laser vaporization of a graphite/(Ni, Co) target is investigated by laser-induced luminescence imaging and spectroscopy of Co atoms, C2 and C3 molecules, and clusters at 1000 °C in flowing 500 Torr Ar. These laser-induced emission images under typical synthesis conditions show that the plume of vaporized material is segregated and confined within a vortex ring which maintains a ∼1 cm3 volume for several seconds. Using time-resolved spectroscopy and spectroscopic imaging, the time for conversion of atomic and molecular species to clusters was measured for both carbon (200 μs) and cobalt (2 ms). This rapid conversion of carbon to nanoparticles, combined with transmission electron microscopy analysis of the collected deposits, indicate that nanotube growth occurs over several seconds in a plume of mixed nanoparticles. By adjusting the time spent by the plume within the high-temperature zone using these in situ diagnostics, single-walled nanotubes of controlled length were grown at an estimated rate of 0.2 μm/s.
Model Predictive Control-Based Fast Charging for Vehicular Batteries (2011)

Battery fast charging is one of the most significant and difficult techniques affecting the commercialization of electric vehicles (EVs). In this paper, we propose a fast charge framework based on model predictive control, with the aim of simultaneously reducing the charge duration, which represents the out-of-service time of vehicles, and the increase in temperature, which represents safety and energy efficiency during the charge process. The RC model is employed to predict the future State of Charge (SOC). A single mode lumped-parameter thermal model and a neural network trained by real experimental data are also applied to predict the future temperature in simulations and experiments respectively. A genetic algorithm is then applied to find the best charge sequence under a specified fitness function, which consists of two objectives: minimizing the charging duration and minimizing the increase in temperature. Both simulation and experiment demonstrate that the Pareto front of the proposed method dominates that of the most popular constant current constant voltage (CCCV) charge method.
Analysis of the transcriptional program induced by Raf in epithelial cells (2001)

Activation of the Raf/MAP kinase pathway is a critical event in tumorigenesis induced by RAS and other oncogenes, a major role of this signaling system being the regulation of cellular transcription factors. To address the contribution of MAP kinase mediated transcriptional changes to the transformed phenotype, we used an inducible form of Raf to analyze early changes in the transcription of some 6000 genes following activation of the kinase in a normal human breast epithelial cell line. Of the more than 120 significant changes in mRNA level detected, genes promoting cell proliferation, invasiveness, and angiogenesis featured prominently. Some of the most strongly induced genes encoded growth factors of the EGF family: Autocrine activation of the EGF receptor was shown to be responsible for the ability of Raf activation to protect these cells from apoptosis induced by detachment of cells from extracellular matrix (anoikis), which is a critical component of the transformed phenotype.
A Novel Tricyclic Polyketide, Vanitaracin A, Specifically Inhibits the Entry of Hepatitis B and D Viruses by Targeting Sodium Taurocholate Cotransporting Polypeptide (2015)

For achieving better treatment and prevention of hepatitis B virus (HBV) infection, anti-HBV agents targeting a new molecule are in great demand. Although sodium taurocholate cotransporting polypeptide (NTCP) has recently been reported to be an essential host factor for HBV entry, there is a limited number of reports that identify new compounds targeting NTCP and inhibiting HBV entry. Here, from an uncharacterized chemical library, we isolated a structurally new compound, named vanitaracin A, which inhibited the process of entry of HBV and hepatitis D virus (HDV). This compound was suggested to directly interact with NTCP and inhibit its transporter activity. Importantly, vanitaracin A inhibited the entry of all HBV genotypes examined and of a clinically relevant nucleos(t)ide analog-resistant HBV isolate.
Magnets faults characterization for Permanent Magnet Synchronous Motors (2009)

Nowadays Permanent Magnet Synchronous Motor (PMSM) are an attractive alternative to induction machines for a variety of applications due to their higher efficiency, power density and wide constant power speed range. In this context the condition monitoring of magnets status is receiving more and more attention since is critical for industrial applications. This paper presents a characterization of rotor faults for such a motor due to local and uniform demagnetization by means of two dimensional (2-D) Finite Element Analysis (FEA) and proposes a new non-invasive method for their detection by means of a Fourier transform of the back-EMF. The proposed approach is then validated for three permanent magnet synchronous motors with different winding configurations.
Biochemical characterization, molecular cloning and expression of laccases – a divergent gene family – in poplar (1999)

The nature of the enzyme(s) involved in the dehydrogenative polymerization of lignin monomers is still a matter of debate. Potential candidates include laccases which have recently received attention due to their capacity to oxidize lignin monomers and close spatial and temporal correlation with lignin deposition. We have characterized two H2O2-independent phenoloxidases with approximate molecular masses of 90 kDa and 110 kDa from cell walls of Populus euramericana xylem that are capable of oxidizing coniferyl alcohol. The 90-kDa protein was purified to apparent homogeneity and extensively characterized at the biochemical and structural levels. To our knowledge, this is the first report of a plant laccase purified to homogeneity from a lignifying tissue of an angiosperm. The cDNA clones corresponding to the 90-kDa and 110-kDa proteins, lac90 and lac110, were obtained by a PCR-based approach using specific oligonucleotides derived from peptide sequences. Sequence analysis indicated that lac90 and lac110 encoded two distinct laccases. In addition, heterologous screening using an Acer pseudoplatanus laccase cDNA enabled us to obtain three additional cDNAs (lac1, lac2, lac3) that did not correspond to lac90 and lac110. The five laccase cDNAs correspond to a highly divergent multigene family but Northern analysis with gene-specific probes indicated that all of the genes are exclusively and abundantly expressed in stems. These results highlight the polymorphism of plant laccases by an integrated biochemical and molecular approach, and provide the tools that will enable us to clearly determine the function of these enzymes in plants by molecular and genetic approaches.
Analogues of Human Calcitonin - II. Influence of Modifications in Amino Acid Positions 1, 8 and 22 on Hypocalcemic Activity in the Rat (1975)

The calcitonin analogues [Val8] -HCT and [Tyr22] -HCT, each with a single modification, and [Val8, Tyr22] -HCT and [Bmp1, Val8] -HCT, with two replaced amino acids were compared with synthetic human calcitonin (HCT) in respect of their hypocalcemic effects in the rat. The introduction of either valine in place of methionine in position 8 or of tyrosine for phenylalanine in position 22 of the HCT molecule yielded analogues 4 to 5 times as potent and nearly twice as long-acting as HCT. The doubly substituted peptide [Val8, Tyr22] -HCT displayed properties closely similar to those of [Val8] -HCT and [Tyr22] -HCT. The analgoue [Bmp1, Val8] -HCT, with a deaminated cysteine residue at the N-terminus, was about 6 times more potent than HCT and slightly longer-acting than [Val8] -HCT.
Illumination distribution from brightness in shadows: Adaptive estimation of illumination distribution with unknown reflectance properties in shadow regions (1999)

This paper describes a new method for estimating the illumination distribution of a real scene from a radiance distribution inside shadows cast by an object in the scene. First, the illumination distribution of the scene is approximated by discrete sampling of an extended light source. Then the illumination distribution of the scene is estimated from a radiance distribution inside shadows cast by an object of known shape onto another object in the scene. Instead of assuming any particular reflectance properties of the surface inside the shadows, both the illumination distribution of the scene and the reflectance properties of the surface are estimated simultaneously, based on iterative optimization framework. In addition, this paper introduces an adaptive sampling of the illumination distribution of a scene. Rather than using a uniform discretization of the overall illumination distribution, we adaptively increase sampling directions of the illumination distribution based on the estimation at the previous iteration. Using the adaptive sampling framework, we are able to estimate overall illumination more efficiently by using fewer sampling directions. The proposed method is effective for estimating an illumination distribution even under a complex illumination environment.
Interaction of human fibrinogen with staphylococci: presence of a binding region on normal and abnormal fibrinogen variants and fibrinogen derivatives (1978)

Abstract Human fibrinogen interacts with pathogenic staphylococci, causing their clumping through an unexplained mechanism. We attempted to characterize the interaction between the staphylococcal fibrinogen receptor(s) and the binding region on the fibrinogen molecule by employing binding studies and the clumping reaction. Binding studies revealed that the Aα chain of human fibrinogen possesses a high affinity for staphylococci, the affinity of the Bβ chain is somewhat less, and the γ chain has no apparent affinity. The binding region seems located on the C-terminal portion of the Aα and Bβ chains because (1) its function is gradually destroyed by progressive degradation with plasmin and (2) neither purified fragment E nor the N-terminal disulfide knot binds to staphylococci. These findings were supported by experiments with abnormal variants of fibrinogen. Fibrinogen Detroit, with a defect in the N-terminal part of the Aα chain, retained full clumping reactivity toward the staphylococcal receptor, as did fibrinogen Paris I, which manifests a defect in the C-terminal portion of the γ chain. After reduction and carboxymethylation, fibrinogen retained its ability to bind to staphylococci; however, the clumping reactivity was lost, suggesting that disulfide bonds contribute not to the binding properties of fibrinogen but only to its ability to clump. The clumping reaction occurred in the presence of diisopropylfluorophosphate at a concentration that inactivated staphylocoagulase and thrombin, indicating that the clumping reaction does not depend on the enzymatic activity of a serine protease type. Other factors, such as pH, chelators, polyanions, and detergents, were examined for their influence on the clumping reaction. The existence of a binding region(s) for staphylococci provides a basis for their use in measurement of normal and abnormal variants of human fibrinogen and its derivatives.
Pulmonary Complications of Acute Spinal Cord Injuries (1987)

The records of 123 consecutive patients admitted with spinal cord injury were examined for the presence of pulmonary complications. Forty-nine had tetraplegia and 23 had paraplegia; the remainder suffered a variety of neurological deficits. Multiple injuries were encountered in 36 patients. Fifty-three pulmonary complications were noted in 44 (35.7%) patients. The most common problems were atelectasis and pneumonia. There were 22 (18%) deaths. Fourteen deaths were related to pulmonary complications. The mean age of patients who died was 52 +/- 13 (SE) compared to 28 +/- 12 for survivors. A mean forced vital capacity (FVC) of 1127 +/- 410 cc in patients suffering respiratory difficulties compared to a FVC of 1865 +/- 85 cc in patients without complications (P less than 0.001). Oxygenation (PaO2 90 +/- 19 torr) was normal in patients without respiratory problems and was abnormal in patients developing problems (PaO2 76 +/- 30 torr; P less than 0.05). Twenty patients were treated with a rotating bed. The complication rate of patients on the bed was only 10%. In conclusion, respiratory problems remain a significant cause of morbidity and mortality in spinal cord injury. The forced vital capacity, blood oxygen tension, and age are predictors of pulmonary complications. The use of a multidisciplinary approach and a rotating bed may minimize these problems.
Changes in phenylpropanoid metabolites associated with homology‐dependent silencing of phenylalanine ammonia‐lyase and its somatic reversion in tobacco (2001)

Gene silencing of phenylalanine ammonia‐lyase (PAL) in transgenic tobacco ( Nicotiana tabacum L.) is manifested phenotypically by reduced growth, altered leaf morphology, and reduced levels of phenylpropanoid compounds. Here we report the rare event of somatic reversion from silencing to PAL over‐expression in tobacco harboring the bean PAL2 gene. This phenomenon allows the comparison of the effects of PAL under‐ and over‐expression in the same plant. A comparison of gene silenced and revertant tissues reveals striking differences in lignin content and monomer composition, and both qualitative and quantitative differences in soluble and cell wall bound phenylpropanoid compounds in the recovered sector.