gebhart/patrepeval huggingface dataset:
Validity of the <i>t-plot</i> Method to Assess Microporosity in Hierarchical Micro/Mesoporous Materials (2014)

The t-plot method is a well-known technique which allows determining the micro- and/or mesoporous volumes and the specific surface area of a sample by comparison with a reference adsorption isotherm of a nonporous material having the same surface chemistry. In this paper, the validity of the t-plot method is discussed in the case of hierarchical porous materials exhibiting both micro- and mesoporosities. Different hierarchical zeolites with MCM-41 type ordered mesoporosity are prepared using pseudomorphic transformation. For comparison, we also consider simple mechanical mixtures of microporous and mesoporous materials. We first show an intrinsic failure of the t-plot method; this method does not describe the fact that, for a given surface chemistry and pressure, the thickness of the film adsorbed in micropores or small mesopores (< 10σ, σ being the diameter of the adsorbate) increases with decreasing the pore size (curvature effect). We further show that such an effect, which arises from the fact that the surface area and, hence, the free energy of the curved gas/liquid interface decreases with increasing the film thickness, is captured using the simple thermodynamical model by Derjaguin. The effect of such a drawback on the ability of the t-plot method to estimate the micro- and mesoporous volumes of hierarchical samples is then discussed, and an abacus is given to correct the underestimated microporous volume by the t-plot method.
Input Nyquist sampling suffices to identify and compensate nonlinear systems (1998)

Nonlinear systems usually cause spectral spreading resulting in an output signal bandwidth greater than that of the input signal. When identifying and compensating nonlinear systems by digital methods, it has been common practice to set the sampling frequency at the Nyquist rate of the output signal. This correspondence presents experimental evidence for the author's proposal that nonlinear systems can be identified and compensated at the lowest possible sampling rate: the Nyquist rate of the input signal.
WND TUNNEL TESTS OF THE UAG 92-170/SF SLOTTED FLAPPED WING SECTION (1994)

Wind tunnel tests have been carried out to determine the characteristics of the UAG92770/SF slotted flap wing section for use on variable geometry sailplanes. This wing section depends on a camber flap to obtain a wide range of operational lift coefficient, and would be mostly operated with the camber flap deflected up. Flap extended lift - drag characteristics of this wing section are comparable to slotted flapped version of the FX 67 VC 770/36 wing section used on the Sigma variable geometry sailplane. Drag coefficient for this wing section lies between that geometry sailplane using a slotted flapped wing section.
Hepatic gene therapy: efficient gene delivery and expression in primary hepatocytes utilizing a conjugated adenovirus-DNA complex. (1993)

Receptor-mediated endocytosis is an effective method for gene delivery into target cells. We have previously shown that DNA molecules complexed with asialoglycoprotein can be efficiently endocytosed by primary hepatocytes and the internalized DNA can be released from endosomes by the use of a replication-defective adenovirus. Because the DNA and virus enter target cells independently, activity enhancement requires high concentrations of adenoviral particles. In this study, adenoviral particles were chemically conjugated to poly(L-lysine) and bound ionically to DNA molecules. Quantitative delivery to primary hepatocytes was achieved with significantly reduced viral titer when the asialoorosomucoid-poly(L-lysine) conjugate was included in the complex. The conjugated adenovirus was used to deliver a DNA vector containing canine factor IX to mouse hepatocytes, resulting in the expression of significant concentrations of canine factor IX in the culture medium. The results suggest that receptor-mediated endocytosis coupled with an efficient endosomal lysis vector should permit the application of targeted and efficient gene delivery into the liver for gene therapy of hepatic deficiencies.
Minimal Size of Coffee Ring Structure (2010)

A macroscopic evaporating water droplet with suspended particles on a solid surface will form a ring-like structure at the pinned contact line due to induced capillary flow. As the droplet size shrinks, the competition between the time scales of the liquid evaporation and the particle movement may influence the resulting ring formation. When the liquid evaporates much faster than the particle movement, coffee ring formation may cease. Here, we experimentally show that there exists a lower limit of droplet size, D(c), for the successful formation of a coffee ring structure. When the particle concentration is above a threshold value, D(c) can be estimated by considering the collective effects of the liquid evaporation and the particle diffusive motion within the droplet. For suspended particles of size approximately 100 nm, the minimum diameter of the coffee ring structure is found to be approximately 10 microm.
Sub-millimeter wave signal generation and detection in CMOS (2009)

Feasibility of CMOS circuits operating at frequencies in the upper millimeter wave and low sub-millimeter frequency regions has been demonstrated. A 140-GHz fundamental mode VCO and a 324-GHz quadruple pushed VCO in 90-nm CMOS, a 410-GHz push-push VCO in 45-nm CMOS, and 180-GHz Schottky diode and 780-GHz plasma wave detectors in 130-nm CMOS have been demonstrated. With the continued scaling of MOS transistors, 1-THz CMOS circuits will be possible.
The LTR72 Mutant of Heat-Labile Enterotoxin of<i>Escherichia coli</i>Enhances the Ability of Peptide Antigens To Elicit CD4<sup>+</sup>T Cells and Secrete Gamma Interferon after Coapplication onto Bare Skin (2002)

Application of antigens with an adjuvant onto bare skin is a needle-free and pain-free immunization procedure that delivers antigens to the immunocompetent cells of the epidermis. We tested here the immunogenicity and adjuvanticity of two mutants of heat-labile enterotoxin (LT) of Escherichia coli, LTK63 and LTR72. Both mutants were shown to be immunogenic, inducing serum and mucosal antibody responses. The application of LTK63 and LTR72 to bare skin induced significant protection against intraperitoneal challenge with a lethal dose of LT. In addition, both LT mutants enhanced the capacity of peptides TT:830-843 and HA:307-319 (representing T-helper epitopes from tetanus toxin and influenza virus hemagglutinin, respectively) to elicit antigen-specific CD4(+) T cells after coapplication onto bare skin. However, only mutant LTR72 was capable of stimulating the secretion of high levels of gamma interferon. These findings demonstrate that successful skin immunization protocols require the selection of the right adjuvant in order to induce the appropriate type of antigen-specific immune responses in a selective and reliable way. Moreover, the use of adjuvants such the LTK63 and LTR72 mutants, with no or low residual toxicity, holds a lot of promise for the future application of vaccines to the bare skin of humans.
Kinetic Analyses of Parathyroid Hormone Clearance as Measured by Three Rapid Immunoassays during Parathyroidectomy (2002)

Automated methods are as suitable as the manual test. The preoperative baseline PTH is necessary but is insufficient for kinetic calculations.
Ground radiation antenna using magnetic coupling structure (2013)

In this paper, radiation performance of a ground radiation antenna using magnetic coupling structure is compared with a conventional planar inverted-F antenna (PIFA) in terms of the impedance bandwidth and radiation efficiency. The size of the proposed ground radiation antenna is 5 × 10 mm2, reduced up to approximately 50% while the impedance bandwidth is obtained as 560 MHz (2174~2734MHz), improved by approximately 300% compared to the PIFA. The size of the ground plane is 50 × 20 mm2, intended for USB dongle and headset applications.
Hydroxyapatite modified chitin as potential hard tissue substitute material (1997)

Calcium hydroxyapatite (HA) powder was incorporated into chitin solutions to form an intimate mixture. Upon casting of this mixture into molds of fixed dimensions with subsequent removal of solvent, HAs containing chitin flexible plates were produced. The amount of (HA) was varied from 10 to 50% by mass of HA. The elastic modulus, yield stress, and elongation to fracture, measured at a crosshead speed of 5 mm/min, of these HAs containing chitin flexible plates were evaluated. The amount of HA in the HA incorporated chitin was found to not significantly change the elastic modulus or elongation to fracture. However, a decrease in the maximum tensile stress with an increase in the HA content was found.
Messenger RNA levels of XPAC and ERCC1 in ovarian cancer tissue correlate with response to platinum-based chemotherapy. (1994)

Nucleotide excision repair is a DNA repair pathway that is highly conserved in nature, with analogous repair systems described in Escherichia coli, yeast, and mammalian cells. The rate-limiting step, DNA damage recognition and excision, is effected by the protein products of the genes ERCC1 and XPAC. We therefore assessed mRNA levels of ERCC1 and XPAC in malignant ovarian cancer tissues from 28 patients that were harvested before the administration of platinum-based chemotherapy. Cancer tissues from patients whose tumors were clinically resistant to therapy (n = 13) showed greater levels of total ERCC1 mRNA (P = 0.059), full length transcript of ERCC1 mRNA (P = 0.026), and XPAC mRNA (P = 0.011), as compared with tumor tissues from those individuals clinically sensitive to therapy (n = 15). In 19 of these tissues, the percentage of alternative splicing of ERCC1 mRNA was assessed. ERCC1 splicing was highly variable, with no difference observed between responders and nonresponders. The alternatively spliced species constituted 2-58% of the total ERCC1 mRNA in responders (median = 18%) and 4-71% in nonresponders (median = 13%). These data suggest greater activity of the DNA excision repair genes ERCC1 and XPAC in ovarian cancer tissues of patients clinically resistant to platinum compounds. These data also indicate highly variable splicing of ERCC1 mRNA in ovarian cancer tissues in vivo, whether or not such tissues are sensitive to platinum-based therapy.
Composition of Corn Steep Water during Steeping (1996)

Corn wet-milling generates large volumes of corn steep water, which is composed of kernel extractives, microbes (principally lactobacilli), numerous products of fermentation processes, and dissolved SO2. In order to understand better the process of steeping and the potential uses of corn steep water, its composition was analyzed and compared at various times during the steeping from four different industrial processes. Of particular interest were the analyses of corn steep water for carbohydrates, amino acids, polypeptides, fatty acids, and other organic compounds, hydrolytic enzymes, heavy metals, and inorganic ions. This study, together with an earlier analysis of corn steep water for myo-inositol phosphates (Hull and Montgomery, 1995), provides a basis for informed judgment of the nutritional and biotechnological value of corn steep water, an abundant byproduct of the corn wet-milling industry. Keywords: Corn steep water; compositional analysis; steeping
Promising Catalyst for Auto Exhaust (1971)

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Core−Shell Nanoporous Electrode for Dye Sensitized Solar Cells:  the Effect of the SrTiO<sub>3</sub> Shell on the Electronic Properties of the TiO<sub>2</sub> Core (2003)

A nanoporous TiO2 electrode coated with a thin SrTiO3 layer was synthesized for photoelectrochemical applications. Introduction of this core−shell electrode to a dye sensitized solar cell increased the open circuit photovoltage while reducing the short circuit photocurrent in comparison with a cell containing the standard noncoated TiO2 electrode. The photovoltage increases is more significant than the photocurrent reduction resulting in a 15% improvement of the overall conversion efficiency of the solar cell. The performance of the TiO2−SrTiO3 core−shell electrode in the dye sensitized solar cell was analyzed by several methods including photocurrent−voltage correlation, spectro-electrochemistry, dark current measurement, IPCE, and photovoltage spectroscopy. The results indicate that the SrTiO3 layer shifts the conduction band of the TiO2 in the negative direction rather than forming energy barrier at the TiO2/electrolyte interface as found for similar coating by other materials. The shift of the TiO2 bands is attributed to a surface dipole that is induced by the SrTiO3 coating.
Ambient backscatter (2013)

We present the design of a communication system that enables two devices to communicate using ambient RF as the only source of power. Our approach leverages existing TV and cellular transmissions to eliminate the need for wires and batteries, thus enabling ubiquitous communication where devices can communicate among themselves at unprecedented scales and in locations that were previously inaccessible. To achieve this, we introduce ambient backscatter, a new communication primitive where devices communicate by backscattering ambient RF signals. Our design avoids the expensive process of generating radio waves; backscatter communication is orders of magnitude more power-efficient than traditional radio communication. Further, since it leverages the ambient RF signals that are already around us, it does not require a dedicated power infrastructure as in traditional backscatter communication. To show the feasibility of our design, we prototype ambient backscatter devices in hardware and achieve information rates of 1 kbps over distances of 2.5 feet and 1.5 feet, while operating outdoors and indoors respectively. We use our hardware prototype to implement proof-of-concepts for two previously infeasible ubiquitous communication applications.
Mechanisms of Cystic Fibrosis Transmembrane Conductance Regulator Activation by S-Nitrosoglutathione (2006)

We investigated the mechanisms by which S-nitrosoglutathione (GSNO) alters cystic fibrosis transmembrane conductance regulator (CFTR) mediated chloride (Cl(-)) secretion across Calu-3 cells, an extensively used model of human airway gland serous cells. Confluent monolayers of Calu-3 cells, grown under an air-liquid interface, were mounted in Ussing chambers for the measurements of chloride short circuit current (I(sc)) and trans-epithelial resistance (R(t)). Addition of GSNO into the apical compartment of these chambers resulted in significant and sustained increase of I(sc) with an IC(50) of 3.2 +/- 1 mum (mean +/- 1 S.E.; n = 6). Addition of either glibenclamide or pre-treatment of Calu-3 cells with the soluble guanylate cyclase inhibitor 1H-(1,2,4)-oxadiazolo[4,3-a]quinoxalin-1-one totally prevented the GSNO-induced increase of I(sc). Conversely, BAY 41-2272, a sGC stimulator, increased I(sc) in a dose-response fashion. The GSNO increase of I(sc) was reversed by addition of two phosphatases (PP2A1, PP2A2) into the apical compartment of Ussing chambers containing Calu-3 monolayers. Oxy-myoglobin (oxy-Mb, 300 mum) added into the apical compartment of Ussing chambers either prior or after GSNO either completely prevented or immediately reversed the increase of I(sc). However, smaller concentrations of oxy-Mb (1-10 mum), sufficient to scavenge NO in the medium (as assessed by direct measurement of NO in the Ussing chamber using an ISO-NO meter) decreased I(sc) partially. Oxy-Mb did not reverse the increase of I(sc) following addition of GSNO and cysteine (50 mum). These findings indicate that GSNO stimulates Cl secretion via both cGMP-dependent and cGMP-independent mechanisms.
Identification of Novel Glycogen Synthase Kinase-3β Substrate-interacting Residues Suggests a Common Mechanism for Substrate Recognition (2006)

Substrate recognition and specificity are essential for the reliability and fidelity of protein kinase function. GSK-3 has a unique substrate specificity that requires prior phosphorylation of its substrates. However, how the enzyme selects its phosphorylated substrates is unknown. Here, we combined in silico modeling with mutagenesis and biological studies to identify GSK-3-substrate interaction sites located within its binding cleft. Protein-protein docking of GSK-3beta and the phosphorylated cAMP responsive element binding protein (pCREB) (using the available experimentally determined structures), identified Phe67, Gln89, and Asn95 of GSK-3beta as putative binding sites interacting with the CREB phosphorylation motif. Mutations of these residues to alanine impaired GSK-3beta phosphorylation of several substrates, without abrogating its autocatalytic activity. Subsequently, expression of the GSK-3beta mutants in cells resulted in decreased phosphorylation of substrates CREB, IRS-1, and beta-catenin, and prevented their suppression of glycogen synthase activity as compared with cells expressing the wild-type GSK-3beta. Our studies provide important additional understanding of how GSK-3beta recognizes its substrates: In addition to prior phosphorylation typically required in GSK-3 substrates, substrate recognition involves interactions with GSK-3beta residues: Phe67, Gln89, and Asn95, which confer a common basis for substrate binding and selectivity, yet allow for substrate diversity.
Video-Rate Far-Field Optical Nanoscopy Dissects Synaptic Vesicle Movement (2008)

We present video-rate (28 frames per second) far-field optical imaging with a focal spot size of 62 nanometers in living cells. Fluorescently labeled synaptic vesicles inside the axons of cultured neurons were recorded with stimulated emission depletion (STED) microscopy in a 2.5-micrometer by 1.8-micrometer field of view. By reducing the cross-sectional area of the focal spot by about a factor of 18 below the diffraction limit (260 nanometers), STED allowed us to map and describe the vesicle mobility within the highly confined space of synaptic boutons. Although restricted within boutons, the vesicle movement was substantially faster in nonbouton areas, consistent with the observation that a sizable vesicle pool continuously transits through the axons. Our study demonstrates the emerging ability of optical microscopy to investigate intracellular physiological processes on the nanoscale in real time.
Use of Fluorescence Resonance Energy Transfer To Estimate Intramolecular Distances in the Msx-1 Homeodomain (1995)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTUse of Fluorescence Resonance Energy Transfer To Estimate Intramolecular Distances in the Msx-1 HomeodomainVeronica Ebu Isaac, Lekha Patel, Tom Curran, and Cory Abate-ShenCite this: Biochemistry 1995, 34, 46, 15276–15281Publication Date (Print):November 1, 1995Publication History Published online1 May 2002Published inissue 1 November 1995https://pubs.acs.org/doi/10.1021/bi00046a036https://doi.org/10.1021/bi00046a036research-articleACS PublicationsRequest reuse permissionsArticle Views99Altmetric-Citations8LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Image and Signal Processing in Diagnostic Ultrasound Imaging (1989)

An overview of signal-processing techniques used in the acquisition, display, manipulation, and analysis of echo scan data is presented. The principles of time-gain compensation, selective enhancement, log compression, fill-in interpolation, edge enhancement, image updating, write zoom, gray scale mapping, black/white inversion, freeze frame, frame averaging, read zoom, thresholding, contrast enhancement, filtering, and region-of-interest definition are reviewed. The concept of gray scale mapping, which dictates how the stored scan data are displayed, is explained with many illustrative examples.
High-mobility window for two-dimensional electron gases at ultrathin AlN∕GaN heterojunctions (2007)

High-conductivity two-dimensional electron gases at AlN∕GaN heterojunctions are reported. The sheet densities can be tuned from ∼5×1012∕cm2to∼5×1013∕cm2 by varying the AlN thickness from 2to7nm. A critical thickness is observed beyond which biaxial strain relaxation and cracking of AlN occur, and a degradation of carrier mobility is seen to occur at extremely high sheet densities. A high-mobility window is identified, within which room-temperature mobility exceeding 1000cm2∕Vs. and sheet densities in the (1–3)×1013∕cm2 are obtained, yielding record low sheet resistances in the range of ∼170Ω∕◻. Interface roughness scattering and strain relaxation are identified as the factors preventing lower sheet resistances at present.
Enantioselective Esterification of Cyclic Dicarboxylic Anhydrides Using Chiral Amino Alcohols as Auxiliaries (1993)

Abstract Cyclic dicarboxylic anhydrides were enantioselectively esterified with the complex formed from cinchonidine, diethylzinc, and methanol, and the half-esters obtained were readily transformed into lactones via reduction and dehydration.
Announcing a special issue of the IEEE journal of quantum electronics on ultrafast optics and electronics (1987)

Provides upcoming special issue information of interest to practitioners and researchers.
Parametric Design. A Review and Some Experiences (1997)

During the last few years there has been an extraordinary development of computer aided tools intended to present or communicate the results of architectural projects. But there has not been a comparable progress in the development of tools intended to assist design to generate architectural forms in an easy and interactive way. Even worst, architects who use the powerful means provided by computers, as a direct tool to create architectural forms are still an exception. Architecture continues to be produced by traditional means using the computer as little more than a drafting tool. The main reasons that may explain this situation can be identified rather easily, although there will be significant differences of opinion. Mine is that it is a mistake trying to advance too rapidly and, for instance, propose integrated design methods using expert systems and artificial intelligence resources when do not have still an adequate tool to generate and modify simple 3D models. The modelling tools we have at the present moment are clearly unsatisfactory. Their principal limitation is the lack of appropriate instruments to modify interactively the model once it has been created. This is a fundamental aspect in any design activity, where the designer is constantly going forward and backwards, reelaborating once and again some particular aspect of the model, or its general layout, or even coming back to a previous solution that had been temporarily abandoned.