gebhart/patrepeval huggingface dataset:
Bowtie limited diffraction beams for low-sidelobe and large depth of field imaging (1995)

Limited diffraction beams such as Bessel beams and X waves have a large depth of field and thus could have many applications. However, these beams have higher sidelobes as compared to conventional focused beams in their focal planes. In this paper, a new class of limited diffraction beams is developed. These beams are termed bowtie limited diffraction beams because they have bowtie shapes in a plane perpendicular to the beam axis. To obtain pulse-echo images of low sidelobes and a large depth of field, a bowtie limited diffraction beam is used in transmission and its 90/spl deg/ rotated response (around the beam axis) is used in reception. Unlike the summation-subtraction method developed previously, this method does not reduce image frame rate or dynamic range of signals and is not motion sensitive. The theory of the bowtie limited diffraction beams is developed. Computer simulation of the theoretical beams under practical conditions, such as finite aperture, finite bandwidth, and causal excitation, is performed with the Rayleigh-Sommerfeld diffraction formula. The simulated beams are very close to those predicted analytically over a large depth of field.
Predicting acidification of North American lakes (1983)

An empirical model for lake acidification developed in Norway also satisfactorily accounts for observed water chemistry in oligotrophic clearwater, softwater lakes elsewhere in Europe and in North America. This model can be used for prediction of lake acidity in response to future changes in loadings of storing acids. The model takes into account both changes in base cation concentrations and changes in alkalinity due to acid inputs
Protein Interactions with Polymer Coatings and Biomaterials (2014)

Protein adsorption is considered to be the most important factor of the interaction between polymeric biomaterials and body fluids or tissues. Water-mediated hydrophobic and hydration forces as well as electrostatic interactions are believed to be the major factors of protein adsorption. A systematic analysis of various monolayer systems has resulted in general guidelines, the so-called "Whitesides rules". These concepts have been successfully applied for designing various protein-resistant surfaces and are being studied to expand the understanding of protein-material interactions beyond existing limitations. Theories on the mechanisms of protein adsorption are constantly being improved due to the fast-developing analytical technologies. This Review is aimed at improving these empirical guidelines with regard to present theoretical and analytical advances. Current analytical methods to test mechanistic hypotheses and theories of protein-surface interactions will be discussed. Special focus will be given to state-of-the-art bioinert and biospecific coatings and their applications in biomedicine.
Inherited predisposition to breast cancer. (1998)

Breast and ovarian cancers sometimes occur in families. Linkage studies in these families have led to the mapping and then cloning of two predisposing genes, BRCA1 and BRCA2. Together these genes probably account for rather less than 5% of all breast and ovarian cancers. In the medium term, understanding the function of the proteins encoded by these genes should lead to a better understanding of how the cancers develop, and the design of new approaches to treatment and prevention. Of more immediate concern is the possibility of genetic testing for cancer susceptibility in families. In multiple-case families, where the BRCA1 or BRCA2 mutation is likely to be present and there are clear clinical decisions to be taken, genetic testing is not controversial. The costs and benefits of wider testing are much less clear.
Synthesis and characterization of oligonucleotides containing conformationally constrained bicyclo[3.1.0]hexane pseudosugar analogs (2004)

Oligodeoxyribonucleotides containing pseudorotationally locked sites derived from bicyclo[3.1.0]hexane pseudosugars have been synthesized using adenosine, thymidine and abasic versions of North- and South-methanocarba nucleosides. The reaction conditions for coupling and oxidation steps of oligonucleotide synthesis have been investigated and optimized to allow efficient and facile solid-phase synthesis using phosphoramidite chemistry. Our studies demonstrate that the use of iodine for P(III) to P(V) oxidation leads to strand cleavage at the sites where the pseudosugar is North. In contrast, the same cleavage reaction was not observed in the case of South pseudosugars. Iodine oxidation generates a 5'-phosphate oligonucleotide fragment on the resin and releases the North pseudosugar into the solution. This side reaction, which is responsible for the extremely low yields observed for the incorporation of the North pseudosugar analogs, has been studied in detail and can be easily overcome by replacing iodine with t-butylhydroperoxide as oxidant.
A Computational Technique for Concept Generation (2005)

Few computational tools exist to assist designers during the conceptual phase of design, and design success is often heavily weighted on personal experience and innate ability. Many well-known methods (e.g. brainstorming, intrinsic and extrinsic searches, and morphological analysis) are designed to stimulate a designer’s creativity, but ultimately still rely heavily on individual bias and experience. Under the premise that quality designs comes from experienced designers, experience in the form of design knowledge is extracted from existing products and stored for reuse in a web-based repository. This paper presents an automated concept generation tool that utilizes the repository of existing design knowledge to generate and evaluate conceptual design variants. This tool is intended to augment traditional conceptual design phase activities and produce numerous feasible concepts early in the design process.
Hemagglutinins from two influenza virus variants bind to sialic acid derivatives with millimolar dissociation constants: a 500-MHz proton nuclear magnetic resonance study (1989)

The equilibrium binding of influenza virus hemagglutinin to derivatives of its cell-surface ligand, sialic acid, was measured by nuclear magnetic resonance (NMR) spectroscopy. Binding was quantified by observing perturbations of sialic acid resonances in the presence of protein. The major perturbation observed was a chemical shift of the N-acetyl methyl resonance, presumably due to the proximity of the methyl group to tryptophan 153. X-31 hemagglutinin binds to the methyl alpha-glycoside of sialic acid with a dissociation constant of 2.8 mM and does not bind to the methyl beta-glycoside. Replacing the 4-hydroxyl group of sialic acid with an acetyl group has little effect, while replacing the 7-hydroxyl group with an acetyl prevents binding. Experiments with sialylated oligosaccharides confirm literature reports that mutations at amino acid 226 change the specificity of hemagglutinin for alpha(2,6) and alpha(2,3) glycosidic linkages. The NMR line broadening of sialyloligosaccharides suggests that sialic acid is the only component that contacts the protein. Saccharides containing two sialic acid residues appear to have two separate binding modes. Hemagglutinin that has undergone a low pH induced conformational change retains the ability to bind sialic acid.
Studies on prostaglandins. VI. Synthesis of 16(S)-methyl-20-methoxy-PGE2 (YPG-209) having oral bronchodilator activity and its analogs. (1980)

16 (S)-Methyl-20-methoxy-PGE2 (YPG-209) (Is), 16 (R)-methyl-20-methoxy-PGE2 (IR) and several analogs, such as 16 (S)-methyl-20-methoxy-PGA2 (XIIIs) and -PGB2 (XIVs), 16-methyl-20-ethoxy-PGE2 (XXVIIa), 16-methyl-20-hydroxymethyl-PGE2 (XXVIa), 16-methyl-17-oxa-ω-dihomo-PGE2 (XXVIIIa) and 20-hydroxymethyl-PGE2 (XXX), were synthesized by Corey's procedure and their biological activities were investigated. Among these derivatives, IS and IR possessed potent oral bronchodilator activity ; the bronchoselectivity of IS was higher than that of IR.
Molecular imaging probe development: a chemistry perspective. (2012)

Molecular imaging is an attractive modality that has been widely employed in many aspects of biomedical research; especially those aimed at the early detection of diseases such as cancer, inflammation and neurodegenerative disorders. The field emerged in response to a new research paradigm in healthcare that seeks to integrate detection capabilities for the prediction and prevention of diseases. This approach made a distinct impact in biomedical research as it enabled researchers to leverage the capabilities of molecular imaging probes to visualize a targeted molecular event non-invasively, repeatedly and continuously in a living system. In addition, since such probes are inherently compact, robust, and amenable to high-throughput production, these probes could potentially facilitate screening of preclinical drug discovery, therapeutic assessment and validation of disease biomarkers. They could also be useful in drug discovery and safety evaluations. In this review, major trends in the chemical synthesis and development of positron emission tomography (PET), optical and magnetic resonance imaging (MRI) probes are discussed.
Rheumatoid Arthritis (2010)

This chapter will familiarize the reader with the epidemiology, diagnosis, and conventional and integrative management of rheumatoid arthritis (RA). It also will address the sex bias of this disease, with a focus on reproductive and hormonal issues. The goal is to provide the clinician with a framework to approach disease management for women with RA, to plan a treatment program, and to discuss the evidence for the more common integrative modalities for treatment of RA.
Relevance of angular momentum conservation in mesoscale hydrodynamics simulations (2007)

The angular momentum is conserved in fluids with a few exceptions such as ferrofluids. However, it can be violated locally in fluid simulations to reduce computational costs. The effects of this violation are investigated using a particle-based simulation method, multiparticle collision dynamics, which can switch on or off angular-momentum conservation. To this end, we study circular Couette flows between concentric and eccentric cylinders, where nonphysical torques due to the lack of the angular-momentum conservation are found whereas the velocity field is not affected. In addition, in simulations of fluids with different viscosities in contact and star polymers in solvent, incorrect angular velocities occur. These results quantitatively agree with the theoretical predictions based on the macroscopic stress tensor.
Diels–Alder Ligation and Surface Immobilization of Proteins (2005)

Schadlos konjugiert: Mithilfe von Diels–Alder-Cycloadditionen können Proteine chemoselektiv ligiert und auf funktionalisierten Glasoberflächen sauber und effizient immobilisiert werden (siehe Schema). Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2001/2006/z502266_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
2-, 5-, and 6-Halo-3-(2(<i>S</i>)-azetidinylmethoxy)pyridines:  Synthesis, Affinity for Nicotinic Acetylcholine Receptors, and Molecular Modeling (1998)

3-(2(S)-Azetidinylmethoxy)pyridine (A-85380) has been identified recently as a ligand with high affinity for nicotinic acetylcholine receptors (nAChRs). Here we report the synthesis and in vitro nAChR binding of a series of 10 pyridine-modified analogues of A-85380. The novel compounds feature a halogen substituent at position 2, 5, or 6 of the 3-pyridyl fragment. Those with the substituents at position 5 or 6, as well as the 2-fluoro analogue, possess subnanomolar affinity for nAChRs in membranes from rat brain. For these ligands, Ki values range from 11 to 210 pM, as measured by competition with (+/-)-[3H]epibatidine. In contrast, 2-chloro, 2-bromo, and 2-iodo analogues exhibit substantially lower affinity. AM1 quantum chemical calculations demonstrate that the bulky substituents at position 2 cause notable changes in the molecular geometry. The high-affinity members of the series and (+)-epibatidine display a tight fit superposition of low-energy stable conformers. The new ligands with high affinity for nAChRs may be of interest as pharmacological probes, potential medications, and candidates for developing radiohalogenated tracers to study nAChRs.
Isomerization Polymerization of 2-Oxazoline. V. Kinetic Studies on the Polymerization of 2-Oxazoline (1973)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIsomerization Polymerization of 2-Oxazoline. V. Kinetic Studies on the Polymerization of 2-OxazolineTakeo Saegusa, Hiroharu Ikeda, and Hiroyasu FujiiCite this: Macromolecules 1973, 6, 3, 315–319Publication Date (Print):May 1, 1973Publication History Published online1 May 2002Published inissue 1 May 1973https://pubs.acs.org/doi/10.1021/ma60033a002https://doi.org/10.1021/ma60033a002research-articleACS PublicationsRequest reuse permissionsArticle Views411Altmetric-Citations65LEARN 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
Quantitative Extraction and Mass Spectrometry Analysis at a Single-Cell Level (2018)

Quantitative live cell mass spectrometry analysis at a subcellular level requires the precisely controlled extraction of subpicoliter volumes of material from the cell, sensitive analysis of the extracted analytes, and their accurate quantification without prior separation. In this study, we demonstrate that localized electroosmotic extraction provides a direct path to addressing this challenge. Specifically, we demonstrate quantitative mass spectrometry analysis of biomolecules in picoliter volumes extracted from live cells. Electroosmotic extraction was performed using two electrodes and a finely pulled nanopipette with tip diameter of <1 μm containing a hydrophobic electrolyte compatible with mass spectrometry analysis. The electroosmotic drag was used to drive analytes out of the cell into the nanopipette. Analyte molecules extracted both from solutions and cell samples were analyzed using nanoelectrospray ionization (nanoESI) directly from the nanopipette into a mass spectrometer. More than 50 metabolites including sugars and flavonoids were detected in positive mode in 2-5 pL volumes of the cytoplasmic material extracted from Allium cepa. Quantification of the extracted glucose was performed using sequential extraction of a known volume of the aqueous solution containing glucose- d<sub>2</sub> standard of known concentration. We found that the ratio of the signal of glucose to glucose- d<sub>2</sub> increased linearly with glucose concentration. This observation indicates that the approach developed in this study enables quantitative analysis of small volumes of metabolites extracted from cells. Furthermore, we observed efficient separation of hydrophilic and hydrophobic analytes through partitioning into the aqueous and hydrophobic electrolyte phase, respectively, which provides additional important information on the molecular properties of extracted metabolites.
Plasma Etching of Composite Silicide Gate Electrodes (1982)

To obtain the advantages of refractory metal silicide composite structures (i.e., silicide/polysilicon/gate oxide) for VLSI applications, these structures have to be defined with little impact on ground rules or subsequent wafer processing. This paper studies film definition using both parallel plate and barrel plasma reactors. The parallel plate system meets all criteria. Etch rates for polysilicon, , and were studied using plasmas. The edge profile of the defined composite structure is dependent on the etch rate ratios of the constituent layers, and these results agree with the classical model for isotropic etching. A process is defined with acceptable edge profiles. Operational IGFET devices with 1–2 μm dimensions have been produced.
Microstructure and Tribological Performance of Laser-Cladded Ni60+<i>h</i>-BN Coatings on Ti-6Al-4V Alloy at High Temperature (2019)

With the expansion of the application range of titanium alloys, the wear protection problem has become increasing prominent due to their poor wear resistance, especially in high-temperature environments. To solve this problem, in this work, Ni60+h-BN coatings on Ti-6Al-4V (TC4) alloys were prepared using a laser cladding technique. The results indicated that the Ni60+h-BN coatings mainly contain the phases of NiTi2, TiN, TiB, (Si, Al)2Cr, and solid solution Fe0.2Ni4.8Ti5, possessing much higher microhardness (1,055.36 ± 16.33 HV0.22) than TC4 substrates (309 ± 10 HV0.2), and the Ni60+h-BN coatings show excellent wear resistance and antifriction properties at 600 °C with the dominant wear mechanism of slight adhesive wear and oxidative wear. As observed by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses, most of the initial h-BN particles in the mixed powders were decomposed and the reinforcements of TiB and TiN were in situ synthesized after high-power laser irradiation, which plays a role in wear resistance, and the metal oxides (TiO2, Al2O3, NiO, and Fe2O3) produced under high-temperature friction condition play a role in lubrication and antifriction at 600 °C. As a consequence, the synergy effect of coupling the reinforcements and the metal oxides contributes to the excellent tribological performance of Ni60+h-BN coatings at 600 °C.
Privacy-Preserving Intra-MME Group Handover via MRN in LTE-A Networks for Repeated Trips (2017)

In Long Term Evolution-Advanced (LTE-A) networks, Mobile Relay Nodes (MRNs) are installed in fast moving buses and trains to connect the passengers' devices to evolved Node B (eNB). However, since the MRNs and eNBs are installed in open environment, they can be compromised to launch security and privacy attacks. In this paper, we propose a privacy preserving intra Mobility Management Entity (MME) group handover scheme in LTE-A networks for repeated trips. Comparing to the existing schemes, the proposed scheme is devised to achieve the following requirements. First, the MRNs should be able to authenticate the received messages so that the messages sent from external attackers can be dropped by the MRNs rather than forwarding them to the core network. Second, the proposed scheme also aims to reduce the computational and signaling overhead and establish secure session keys. Third, the scheme aims to prevent MRNs and eNBs from tracking passengers' locations especially if they take same trip regularly. Our analysis demonstrates that the proposed scheme can achieve our security and privacy objectives. Our performance evaluations demonstrate that the proposed scheme requires a few number of messages and low computation overhead.
Platinum plasmonic nanostructure arrays for massively parallel single-molecule detection based on enhanced fluorescence measurements (2011)

We fabricated platinum bowtie nanostructure arrays producing fluorescence enhancement and evaluated their performance using two-photon photoluminescence and single-molecule fluorescence measurements. A comprehensive selection of suitable materials was explored by electromagnetic simulation and Pt was chosen as the plasmonic material for visible light excitation near 500 nm, which is preferable for multicolor dye-labeling applications like DNA sequencing. The observation of bright photoluminescence (λ = 500-600 nm) from each Pt nanostructure, induced by irradiation at 800 nm with a femtosecond laser pulse, clearly indicates that a highly enhanced local field is created near the Pt nanostructure. The attachment of a single dye molecule was attempted between the Pt triangles of each nanostructure by using selective immobilization chemistry. The fluorescence intensities of the single dye molecule localized on the nanostructures were measured. A highly enhanced fluorescence, which was increased by a factor of 30, was observed. The two-photon photoluminescence intensity and fluorescence intensity showed qualitatively consistent gap size dependence. However, the average fluorescence enhancement factor was rather repressed even in the nanostructure with the smallest gap size compared to the large growth of photoluminescence. The variation of the position of the dye molecule attached to the nanostructure may influence the wide distribution of the fluorescence enhancement factor and cause the rather small average value of the fluorescence enhancement factor.
Projection−Reconstruction Technique for Speeding up Multidimensional NMR Spectroscopy (2004)

The acquisition of multidimensional NMR spectra can be speeded up by a large factor by a projection-reconstruction method related to a technique used in X-ray scanners. The information from a small number of plane projections is used to recreate the full multidimensional spectrum in the familiar format. Projections at any desired angle of incidence are obtained by Fourier transformation of time-domain signals acquired when two or more evolution intervals are incremented simultaneously at different rates. The new technique relies on an established Fourier transform theorem that relates time-domain sections to frequency-domain projections. Recent developments in NMR instrumentation, such as increased resolution and sensitivity, make fast methods for data gathering much more practical for protein and RNA research. Hypercomplex Fourier transformation generates projections in symmetrically related pairs that provide two independent "views" of the spectrum. A new reconstruction algorithm is proposed, based on the inverse Radon transform. Examples are presented of three- and four-dimensional NMR spectra of nuclease A inhibitor reconstructed by this technique with significant savings in measurement time.