gebhart/patrepeval huggingface dataset:
In vivo Magnetic Resonance Imaging of Tumor Protease Activity (2014)

Increased expression of cathepsins has diagnostic as well as prognostic value in several types of cancer. Here, we demonstrate a novel magnetic resonance imaging (MRI) method, which uses poly-L-glutamate (PLG) as an MRI probe to map cathepsin expression in vivo, in a rat brain tumor model. This noninvasive, high-resolution and non-radioactive method exploits the differences in the CEST signals of PLG in the native form and cathepsin mediated cleaved form. The method was validated in phantoms with known physiological concentrations, in tumor cells and in an animal model of brain tumor along with immunohistochemical analysis. Potential applications in tumor diagnosis and evaluation of therapeutic response are outlined.
Potential of cannabidiol for the treatment of viral hepatitis (2017)

Cannabidiol exhibited <i>in vitro</i> activity against viral hepatitis C. <b>Abbreviations Used</b>: CB2: Cannabis receptor 2, CBD: Cannabidiol, DNA: Deoxyribonucleic acid, HBV: Hepatitis B virus, HCV: Hepatitis C virus, HIV/AIDS: Human immunodeficiency virus/acquired immune deficiency syndrome, HSC: Hepatic stellate cells, MTS: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium, PCR: Polymerase chain reaction.
Phosphorylation and destabilization of human period I clock protein by human casein kinase Iε (2000)

Period (PER), a central component of the circadian clock in Drosophila, undergoes daily oscillation in abundance and phosphorylation state. Here we report that human casein kinase I epsilon (hCKI epsilon) can phosphorylate human PER I (hPER I). Purified recombinant hCKI epsilon (but not a kinase negative mutant of hCKI epsilon, hCKI epsilon-K38R) phosphorylated hPER I in vitro. When co-transfected with wild-type hCKI epsilon, in 293T cells, hPER I showed a significant increase in phosphorylation as evidenced by a shift in molecular mass. Furthermore, phosphorylation of hPER I by hCKI epsilon caused a decrease in protein stability in hPER I. Whereas phosphorylated hPER I had a half-life of approximately 12 h, unphosphorylated hPER I remained stable in the cell for > 24 h. hPER I protein could also be co-immunoprecipitated with transfected hCKI epsilon as well as endogenous hCKI epsilon, indicating physical association between hPER I and hCKI epsilon proteins in vivo.
UV screen progenitors. Thermally labile urethane derivatives of hydroxyphenylbenzotriazoles and hydroxybenzophenones (1978)

Abstract UV‐curable formulations do not UV cure when hydroxybenzophenone or hydroxyphenylbenzotriazole UV screens are added to them. Reaction of these UV screens with alkyl or aryl isocyanates gives urethane derivatives in high yields. These derivatives do not impede UV cures when they are incorporated in UV‐curable formulations at relatively high levels (3%–5%). After completion of the UV cure, the urethane derivatives are catalytically decomposed by heating to regenerate the corresponding UV screen within the cured coating.
Flue Gas Recirculation in a Gas Turbine: Impact on Performance and Operational Behavior (2011)

The rigorous reduction of greenhouse gas emissions in the upcoming decades is only achievable with contribution from the following strategies: production efficiency, demand reduction of energy and carbon dioxide (CO2) capture from fossil fueled power plants. Since fossil fueled power plants contribute largely to the overall global greenhouse gas emissions (> 25% [1]), it is worthwhile to capture and store the produced CO2 from those power generation processes. For natural-gas-fired power plants, post-combustion CO2 capture is the most mature technology for low emissions power plants. The capture of CO2 is achieved by chemical absorption of CO2 from the exhaust gas of the power plant. Compared to coal fired power plants, an advantage of applying CO2 capture to a natural-gas-fired combined cycle power plant (CCPP) is that the reference cycle (without CO2 capture) achieves a high net efficiency. This far outweighs the drawback of the lower CO2 concentration in the exhaust. Flue Gas Recirculation (FGR) means that flue gas after the HRSG is partially cooled down and then fed back to the GT intake. In this context FGR is beneficial because the concentration of CO2 can be significantly increased, the volumetric flow to the CO2 capture unit will be reduced, and the overall performance of the CCPP with CO2 capture is increased. In this work the impact of FGR on both the Gas Turbine (GT) and the Combined Cycle Power Plant (CCPP) is investigated and analyzed. In addition, the impact of FGR for a CCPP with and without CO2 capture is investigated. The fraction of flue gas that is recirculated back to the GT, need further to be cooled, before it is mixed with ambient air. Sensitivity studies on flue gas recirculation ratio and temperature are conducted. Both parameters affect the GT with respect to change in composition of working fluid, the relative humidity at the compressor inlet, and the impact on overall performance on both GT and CCPP. The conditions at the inlet of the compressor also determine how the GT and water/steam cycle are impacted separately due to FGR. For the combustion system the air/fuel-ratio (AFR) is an important parameter to show the impact of FGR on the combustion process. The AFR indicates how close the combustion process operates to stoichiometric (or technical) limit for complete combustion. The lower the AFR, the closer operates the combustion process to the stoichiometric limit. Furthermore, the impact on existing operational limitations and the operational behavior in general are investigated and discussed in context of an operation concept for a GT with FGR.
Formation of Hierarchically Organized Zeolites by Sequential Intergrowth (2013)

Make intergrowth, not war! Hierarchically organized MFI zeolites with micro-, meso-, and macroporosity (see scheme) in one structure were made by sequential intergrowth by using a simple organic structure-directing agent (OSDA) without meso- or macroporogens. The use of an OSDA that imperfectly fits the zeolite framework generated very thin zeolite plates with 90° rotational intergrowth.
Y-Junction semiconductor laser arrays: Part I--Theory (1987)

A general formulation for the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Y</tex> -junction semiconductor laser array is developed and analytic solutions are obtained for the important special case of identical waveguides. Modal thresholds, resonances, near-field, and far-field patterns are derived for the array modes. We show that the minimum threshold mode has identical modal intensities (except in the outermost waveguides) and the modal amplitudes are all in-phase. Thus the dominant mode radiates in a centered, narrow, single-lobe beam. Because the injected charges are utilized uniformly and efficiently, the mode is predicted to remain stable above threshold. All other array modes are shown to resonate at the same wavelength as the dominant mode, hut at increased thresholds.
Testing For Parasitic Lasing With Controlled Retroreflection (1993)

Controlled-retroreflection technique provides new capability to test safely for parasitic oscillations in laser. Continuously variable reflector adjusted continuously over dynamic range of about 3 decades by rotation of quarter-wave plate about optical axis. Neutral-density filter establishes maximum reflectivity. By selection of neutral-density filters and continuous adjustment, reflector made to have any reflectivity from about 1 down to 10 to the negative 8th power.
Investigation of the lectin-like binding domains in pertussis toxin using synthetic peptide sequences. Identification of a sialic acid binding site in the S2 subunit of the toxin. (1992)

Synthetic peptides corresponding to selected sequences in the S2 and S3 subunits of pertussis toxin were prepared and evaluated for their ability to inhibit the binding of biotinylated pertussis toxin and three biotinylated sialic acid specific plant lectins to fetuin and asialofetuin. The screening results indicated that two regions in the S2 subunit corresponding to amino acids 78-98 and 123-154 inhibited pertussis toxin binding to fetuin at submillimolar concentrations, while S3 sequences corresponding to amino acids 87-108 and 134-154 inhibited pertussis toxin-biotin binding to asialofetuin albeit with lower affinity. These results confirm earlier findings, which suggest that the S2 subunit is responsible for binding sialylated glycoconjugates. This was further confirmed by the ability of S2 peptides to inhibit the binding of the lectins from Maackia amurensis and wheat germ to fetuin. Two additional peptides from the S2 subunit of pertussis toxin corresponding to sequences 9-23 and 1-23 were found to contain within their sequences a 6-amino acid fragment which has strong homology with a sequence in wheat germ agglutinin that has been shown to be a component of the sialic acid binding site as determined by x-ray crystallography. One of these sequences from S2 (9-23) was biotinylated and evaluated for its ability to bind to carbohydrate. Through a series of experiments using fetuin, asialofetuin, asialoagalactofetuin, and simple saccharides, the biotinylated peptide was shown to bind with high affinity to sialic acid-containing glycoconjugates indicating that these sequences within the S2 subunit of pertussis toxin also play an important role in binding sialic acid.
Investigation on a bar detector with 3D position decoding scheme (2005)

Simulation studies were performed to find optimum design parameters for a bar detector allowing 3D position decoding of impinging gamma rays. This design incorporates surface treatment, system geometry, photo-sensors, scintillators, and a more robust positioning algorithm. The bar detector simulated consists of a long scintillation crystal, ranged from 5 cm to 20 cm, with a relatively small cross section (4times4 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), coupled to two photo sensors, one on each end. Statistical based positioning scheme has been developed to improve positioning accuracy. The method maps event characterization vectors to the associated position based on chi square error. Our simulation shows that a 5cm long bar detector can achieve ~1mm FWHM spatial resolution for a 511 keV gamma photon. The performance improvement of the new positioning scheme over a linear estimator were over 70%. Grounded surface with reflector found to be the most optimum surface condition with respect to the steepest and linear correlation of photo sensor signals. Experimental measurements are in progress to validate the simulation results
CXC Chemokine Ligand 12 (Stromal Cell-Derived Factor 1α) and CXCR4-Dependent Migration of CTLs toward Melanoma Cells in Organotypic Culture (2005)

Studies in experimental animal models have demonstrated that chemokines produced by tumor cells attract chemokine receptor-positive T lymphocytes into the tumor area, which may lead to tumor growth inhibition in vitro and in vivo. However, in cancer patients, the role of chemokines in T lymphocyte trafficking toward human tumor cells is relatively unexplored. In the present study, the role of chemokines and their receptors in the migration of a melanoma patient's CTL toward autologous tumor cells has been studied in a novel organotypic melanoma culture, consisting of a bottom layer of collagen type I with embedded fibroblasts followed successively by a tumor cell layer, collagen/fibroblast separating layer, and, finally, a top layer of collagen with embedded fibroblasts and T cells. In this model, CTL migrated from the top layer through the separating layer toward tumor cells, resulting in tumor cell apoptosis. CTL migration was mediated by chemokine receptor CXCR4 expressed by the CTL and CXCL12 (stromal cell-derived factor 1alpha) secreted by tumor cells, as evidenced by blockage of CTL migration by Abs to CXCL12 or CXCR4, high concentrations of CXCL12 or small molecule CXCR4 antagonist. These studies, together with studies in mice indicating regression of CXCL12-transduced tumor cells, followed by regression of nontransduced challenge tumor cells, suggest that CXCL12 may be useful as an immunotherapeutic agent for cancer patients, when transduced into tumor cells, or fused to anti-tumor Ag Ab or tumor Ag.
Synthesis and Characterization of Biodegradable Cationic Poly(propylene fumarate-<i>c</i><i>o</i>-ethylene glycol) Copolymer Hydrogels Modified with Agmatine for Enhanced Cell Adhesion (2002)

We synthesized positively charged biodegradable hydrogels by cross-linking of agmatine-modified poly(ethylene glycol)-tethered fumarate (Agm-PEGF) and poly(propylene fumarate-co-ethylene glycol) (P(PF-co-EG)) to investigate the effect of the guanidino groups of the agmatine on hydrogel swelling behavior and smooth muscle cell adhesion to the hydrogels. The weight swelling ratio of these hydrogels at pH 7.0 increased from 279 +/- 4 to 306 +/- 7% as the initial Agm-PEGF content increased from 0 to 200 mg/g of P(PF-co-EG), respectively. The diffusional exponents, n, during the initial phase of water uptake were independent of the initial Agm-PEGF content and were determined to be 0.66 +/- 0.08, 0.71 +/- 0.07, and 0.60 +/- 0.05 for respective initial Agm-PEGF contents of 0, 100, and 200 mg/g. The heat of fusion of water present in the hydrogels increased from 214 +/- 11 to 254 +/- 4 J/g as the initial Agm-PEGF content increased from 0 to 200 mg/g. The number of adherent smooth muscle cells increased dose-dependently from 15 +/- 6 to 75 +/- 7% of the initial seeding density as the initial Agm-PEGF content increased from 0 to 200 mg/g. These results suggest that the incorporation of the guanidino groups of agmatine into P(PF-co-EG) hydrogels increases the hydrogel free water content and the total water content of the hydrogels and also enhances cell adhesion to the hydrogels.
Surface Characterization of Virulent <i>Treponema pallidum</i> (1980)

Characterization of the surface of Treponema pallidum was accomplished by [(125)I]lactoperoxidase-catalyzed iodination of intact organisms and sensitive radioimmunoprecipitation and gel electrophoresis technology. At least 11 outer membrane proteins with molecular weights ranging from 89,000 (89K) to 20K were identified, and all elicited high titers of antibody in experimentally infected rabbits. Proteins of 89.5K, 29.5K, and 25.5K previously implicated as ligands involved in attachment (J. B. Baseman and E. C. Hayes, J. Exp. Med. 151:573-586, 1980) were found to reside on the treponemal surface. Low levels of the 89.5K treponemal protein were released by high salt concentrations, whereas the remaining comigrating material was neither radioiodinated nor released with selective detergents. Other lower-molecular-weight (60K, 45K, and 30K) surface proteins were extracted with octyl glucoside detergent, suggesting their hydrophobic interaction with the external membrane. The molecular organization of surface proteins was studied by employing the cross-linker dithiobis(succinimidyl)-propionate, and data suggested the presence of a highly fluid envelope resulting in random collisions by the surface proteins. The biological function of the treponemal outer envelope proteins was evaluated using, as the indicator system, adherence of T. pallidum to monolayer cultures of eucaryotic cells. Trypsin treatment of motile, freshly harvested organisms decreased the extent of surface parasitism to normal rabbit testicular cells, reinforcing the idea of the proteinaceous nature and role of treponemal ligands for attachment. Other data supported functional and antigenic relatedness among the implicated ligands. Finally, brief periodate treatment of human epithelial (HEp-2) and normal rat testicular cells as well as casein-elicited rabbit peritoneal macrophages significantly reduced the extent of treponemal parasitism, suggesting a role of specific host membrane molecules as mediators of attachment.
On-chip surface-enhanced Raman spectroscopy (SERS)-linked immuno-sensor assay (SLISA) for rapid environmental-surveillance of chemical toxins (2015)

The increasing threat of an intentional (attack) or accidental release of toxins, in particular chemical toxins, including chemical warfare agents (CWAs) and toxic industrial chemicals (TICs) has increased public fear. The major problem in such attacks/accidents is to detect toxins present in very low levels. Indeed, several detection techniques are currently being used for the same. However, none of them meet the most critical requirements of a RISE (Rapid, Inexpensive, Simple and Effective) detect-to-protect class of biosensors. To address this critical demand our group has developed a prototype lab-on-a-chip (LOC) using a colloidal silver-based, surface-enhanced Raman spectroscopy (SERS)-linked immuno-sensor assay (SLISA). The LOC-SLISA was tested for the measurement of RAD54, a stress-marker protein expressed by yeast in response to hydrogen peroxide (H2O2), a toxin in the EPA priority list of chemical toxins. We found SLISA has good correlation in accuracy with the traditional ELISA technique and outperforms the latter by being rapid and easy-to-use. SLISA is more sensitive, provides qualitative information on immuno-sensor’s chemical characterization and antigen-antibody binding, and allows direct detection with minimal or no chance of uncertainty, which is a stringent limitation of all label-based biosensor technologies including ELISA. For translational significance of our work, we correlated our results to U.S. EPA (environmental protection agency) defined risk exposure guideline levels of H2O2 to validate the commercial potential of our on-chip SLISA. The label-free, cell-based and RISE detection offered by SERS can allow development of biomedical and environmental sensor technology (BEST) needed for direct, rapid and continuous monitoring of human health and environment
Evaluating Treatment Methods for Enhancing Microfracture Conductivity in Tight Formations (2013)

Abstract Most microfractures generated within a complex fracture network return to a closed state soon after the release of hydraulic pressure, unless propping agent has been successfully placed inside these fractures. However, particle size and proppant density control the success of such placement. This paper presents the results of a laboratory study that demonstrates and quantifies the effectiveness of methods for enhancing and sustaining the conductivity of microfractures in tight formations. This study examines the conductivity performance of placing microproppant particulates compared to performing an acid fracturing treatment in a created fracture. Various shale core samples were obtained and split along the core length to create artificial fracture faces. Before placement of microproppant into the fracture, the split core fracture faces were first treated with an aqueous-based surface modification agent (ASMA) solution that creates tacky sites to capture any proppant exposed to the treated surface and to mitigate proppant settling. This was then followed by exposure to microproppant slurry. The core halves were then reassembled for core flow testing under closure stress. An acid fracturing treatment administered through the split core fracture involved injection of a sequence of materials that slowly releases organic acid and inorganic acid to etch fracture faces, forming gaps or channels within the fractures, by allowing acid to efficiently dissolve the solid structures on the split core fracture faces. The experimental results are presented by examining the reliability of ASMA treatments to mitigate proppant settling. A permeability comparison of the fractured cores, with and without treatment with ASMA and proppant slurry, demonstrates a dramatic increase to permeability in the treated cores. Permeability measurements of acidized split cores also demonstrate a drastic improvement compared to those of untreated split cores, indicating the importance of maintaining acid activity to maximize fracture etching effectiveness.
A Convenient Laboratory Preparation of Cyanogen (1990)

Abstract A convenient laboratory scale preparation of cyanogen has been developed. This new method generates cyanogen from the pyrolysis of diacetyl-glyoxime which can be easily prepared from glyoxime.
A thermally robust phase change memory by engineering the Ge/N concentration in (Ge, N)<inf>x</inf>Sb<inf>y</inf>Te <inf>z</inf> phase change material (2012)

Phase change memory (PCRAM) is an ideal embedded memory due to its simple BEOL process and low voltage operation. Industrial and automotive applications of PCRAM, however, have not been realized because of poor high temperature properties of the conventional Ge <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> Sb <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> Te <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> phase-change material [1–3]. We have previously reported a special Ge <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf> Sb <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</inf> Te <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">z</inf> material along the Ge and Sb <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> Te <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> tie line that showed superior high temperature performance. In this work we have further enhanced our previous “golden” material by incorporating nitrogen and engineering the Ge/N concentration. In order to rapidly explore a range of new materials a fast method to test retention behavior by laser melt-quenching is adopted which yields retention data on blanket films consistent with device results. A new material with special Ge/N concentration with excellent high temperature retention is discovered. The new material demonstrated nearly 100% yield in a 256 Mb test chip after 160 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sup> C, 84 hrs baking, with projected 10-year retention at 120 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sup> C. (> 9,000 years at 85 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sup> C.)
Further Studies on the Acceleration Sensitivity of Quartz Resonators (1983)

Abstract : Further studies on the acceleration sensitivity of quartz resonators have been performed. These studies have included conventional AT, strip AT, GT, IT, AK, and SC-cut resonators. No significant differences have been found in the best achievable acceleration sensitivities of the various cuts. The dependence of the acceleration sensitivity of 4-point mounted SC-cut resonators on design parameters and operating conditions has been investigated. These parameters include blank geometry, angle of cut, mounting orientation, temperature, drive current, and overtone. No significant systematic variation of acceleration sensitivity has been found as a function of any of these parameters except overtone for the same resonator.