gebhart/patrepeval huggingface dataset:
Total synthesis of erythromycins. 4. Total synthesis of erythronolide B (1978)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTotal synthesis of erythromycins. 4. Total synthesis of erythronolide BE. J. Corey, Sunggak Kim, Sung-Eun Yoo, K. C. Nicolaou, Lawrence S. Melvin Jr., Daniel J. Brunelle, J. R. Falck, Eugene J. Trybulski, Robert Lett, and Peter W. SheldrakeCite this: J. Am. Chem. Soc. 1978, 100, 14, 4620–4622Publication Date (Print):July 1, 1978Publication History Published online1 May 2002Published inissue 1 July 1978https://pubs.acs.org/doi/10.1021/ja00482a063https://doi.org/10.1021/ja00482a063research-articleACS PublicationsRequest reuse permissionsArticle Views2937Altmetric-Citations142LEARN 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
Adhesion and Signaling Mediated by the Cytoplasmic Tails of Leucocyte Integrins (1998)

Integrins not only mediate cell adhesion but also contribute to a variety of other cellular processes including proliferation, cytokine production, cytotoxicity and apoptosis. They act as bi-directional signal transducers, mediating signaling from inside-to-outside the cell and from outside-to-inside the cell. Evidence is emerging that signaling through leukocyte integrins (beta 2 and beta 7) is distinct from signaling by the more widely distributed beta 1 integrins. Here we discuss the role of the cytoplasmic domains of leukocyte integrins and that of cytosolic proteins that bind integrins in mediating signal transduction. Distinct sites in the alpha as well as the common beta chain contribute to this process. We also show that beta 2 integrin distribution on the cell surface is of particular relevance for leukocytes to rapidly alter their adhesive state and display their highly dynamic adhesive behavior. From these and recently published findings the picture is arising that particular cell functions may be supported by integrin-specific signaling pathways.
Intramolecular energy transfer in heteroleptic red phosphorescent dopants (2006)

Intramolecular energy transfer in heteroleptic red phosphorescent dopant materials with mixed ligand units in one molecule was studied. 1-phenylisoquinoline (piq) and phenylpyridine (ppy) moieties were introduced as ligands for Ir based phosphorescent dopants and light emission mechanism was investigated. Intramolecular energy transfer from ppy ligand to piq ligand resulted in pure red emission without any green emission from ppy. Current efficiency of red devices was improved from 4to4.8cd∕A by using mixed ligand structures.
Abort-safe spacecraft rendezvous under stochastic actuation and navigation uncertainty (2021)

We propose a tractable approach to generate abort-safe trajectories for spacecraft rendezvous that guarantees safety, i.e., the spacecraft does not enter a keep-out set defined around the rendezvous target. We guarantee safety of the rendezvous trajectory even in the event of propulsion failure and in the presence of stochastic uncertainty in actuation and navigation. We use a combination of stochastic reachability, computational geometry, and optimization to synthesize a nominal rendezvous trajectory and its associated controller. The designed trajectory is such that safe recovery, in the event of a propulsion failure, is guaranteed with pre-specified, sufficiently high probability. The recovery controllers are available when needed via an offline pre-computation, which significantly reduces the online computational effort. Numerical experiments show the efficacy of the proposed approach.
Tailor‐made Molecular Cobalt Catalyst System for the Selective Transformation of Carbon Dioxide to Dialkoxymethane Ethers (2017)

Abstract Herein a non‐precious transition‐metal catalyst system for the selective synthesis of dialkoxymethane ethers from carbon dioxide and molecular hydrogen is presented. The development of a tailored catalyst system based on cobalt salts in combination with selected Triphos ligands and acidic co‐catalysts enabled a synthetic pathway, avoiding the oxidation of methanol to attain the formaldehyde level of the central CH 2 unit. This unprecedented productivity based on the molecular cobalt catalyst is the first example of a non‐precious transition‐metal system for this transformation utilizing renewable carbon dioxide sources.
Activation of Human B Lymphocytes (1979)

Abstract The precursor of the pokeweed mitogen (PWM)-induced anti-sheep red blood cell (SRBC) plaque-forming cell (PFC) in human peripheral blood was characterized. By a variety of purification procedures, it was demonstrated to be a lymphocyte with surface characteristics of a B cell. Furthermore, it was demonstrated to bind to sheep erythrocytes (E) and thus segregated with the E-rosetting T cells when T cell enrichment was performed by differential fractionation of E-rosetting cells. This binding of the PFC precursor to E was blocked by pretreating the lymphocyte with anti-human Ig before E rosetting, indicating that the PFC precursor specifically bound to SRBC by a surface Ig molecule with binding specificity for sheep red blood cell determinants. Hence, the precursor of the PWM-triggered anti-SRBC PFC is a B lymphocyte with surface Ig expressing specificity for SRBC.
On Fairness in Face Albedo Estimation (2022)

Digital avatars will be crucial components for immersive telecommunication, gaming, and the coming metaverse. Unfortunately, current methods for estimating the facial appearance (albedo) are biased to estimate light skin tones. This talk raises awareness of the problem with an analysis of (1) dataset biases and (2) the light/albedo ambiguity. We show how these problems can be ameliorated by recent advances, improving fairness in albedo estimation.
Site-specific PEGylation using phage display system. (2002)

近年, PEG化蛋白質の臨床応用が試みられ, 目覚しい成果をあげている. しかし, これまで用いられてきた方法では, 蛋白のαアミノ基に対して非特異的にPEGが結合するため, 必然的に比活性低下を招いてしまっている. そのため, いまだPEG化蛋白質の臨床応用は一部の蛋白質に限定されている. そこで, PEGの結合部位を制御することで比活性低下を回避しうる部位特異的PEGylation法の開発が試みられてきたが, 問題点も多くいまだ実用化には至っていない. そこで本稿では, それらの問題を解決すべく, 筆者らが開発した新たな部位特異的PEGylationについて概説する.
Efficient Synthesis of Optically Active 4,5-Dihydroxy-2,3,4,5-tetrahydro-1H-1-benzazepine Derivatives Utilizing Lipase-Catalyzed Transesterification (2006)

As an efficient and enantioselective synthesis of the 4,5-dihydroxy-benzazepine compounds, the syntheses of optically active 5-0-protected trans-4,5-dihydroxybenzazepine derivatives were accomplished. The trans-7-chloro-4-hydroxy-5-methoxymethoxy-1 -(p-toluenesulfonyl)-2,3,4,5-tetrahydro-1H-1-benzazepine [(±)-4] was kinetically resolved by lipase-catalyzed transesterification. The optically active 4* was isomerized into the cis compound (6*) utilizing the Mitsunobu esterification followed by hydrolysis. The chiral compounds (4* and 6*) were converted to the 4,5-bismethoxymethoxy compounds (7*-10*), which were the intermediates for the compounds (2a, b and 3a, b).
Nanopore fluidic SERS (2014)

We describe a technology combining nanopore fluidic with surface enhanced Raman spectroscopy (SERS) for real-time, single molecule detection. After optimization of both optical and device design, we can control the nanopore like a valve for molecule motions and detect a single nucleotide even at 10 ms.
Accurate Picture of Cycling Degradation in HfO2-FeFET Based on Charge Trapping Dynamics Revealed by Fast Charge Centroid Analysis (2021)

We establish an accurate picture of cycling degradation in HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> -FeFET based on the dynamics of various kinds of trap charges (e:electron/h+:hole, stable/unstable, program-induced/read-induced) revealed by fast charge centroid analysis. A part of e trapped at HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> /SiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> interface, which is unrelated to ferroelectricity and unstable before the cycling degradation, becomes unrecoverable after cycling. By calculating its impact on Vth, of FeFET and clarifying the behavior of spontaneous polarization during cycling, we found that the amount of h+-trapping increases with cycling. This additional h+-trapping, which is accompanied with erase operation and disappears with program operation, is the most critical factor for Vth, window narrowing and accelerated by cycling-induced unrecoverable trapped e. Not only e-trapping but also its stabilization should be suppressed for higher endurance.
A quantitative, non-isotopic bioassay for interleukin 2 (1985)

A quantitative bioassay for IL2 is described in which an electronic particle counter is used to measure IL2-mediated proliferation of an IL2-dependent cell line. The assay requires no radioisotopes, is comparable to tritiated thymidine incorporation and can be completely performed in about 28 hours. It can also be used to measure inhibition of IL2-mediated proliferation.
ChemInform Abstract: Kinetic Resolution of Racemic 1‐Heteroarylalkanols by Asymmetric Esterification Using Diphenylacetic Acid with Pivalic Anhydride and a Chiral Acyl‐Transfer Catalyst. (2011)

Abstract The first efficient non‐enzymatic method for providing optically active 1‐heteroarylalkanol derivatives by kinetic resolution is given.
Multiwavelength all-optical TDM switching using a semiconductor optical amplifier in a loop mirror (1999)

We report simultaneous all-optical switching of multiple wavelengths using an optical loop mirror with an asymmetrically placed semiconductor optical amplifier. Switching is shown for 14-wavelength channels (across 14-nm bandwidth) with switching contrast of 10-23 dB.
Figure S3 from UGT2B17 Expedites Progression of Castration-Resistant Prostate Cancers by Promoting Ligand-Independent AR Signaling (2023)

&lt;p&gt;Figure S3: AR knockdown diminished UGT2B17-stimulated gene upregulation&lt;/p&gt;
Immunoglobulin secretion and phosphorylation of common proteins are induced by IL-2, IL-4, and IL-6 in the factor responsive human B cell line, SKW6.4. (1993)

After the binding of IL-2, IL-4, or IL-6 to their respective receptors on activated human B cells, a multistep cascade of intracellular events is initiated that results in the secretion of Ig. However, it is not known whether these different cytokine receptors use common or divergent signal transduction pathways to stimulate Ig secretion. Therefore, we examined the signaling mechanisms used by a human lymphoblastoid cell line arrested at a late stage of differentiation, SKW6.4, that secretes IgM following stimulation with IL-2, IL-4, or IL-6 alone. Our study demonstrated that IL-2, IL-4, and IL-6-stimulation of IgM secretion by SKW6.4 cells was inhibited by either the serine/threonine kinase inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperizine dihydrochloride (H7) or the tyrosine kinase inhibitor, genistein. To investigate the early phosphorylation events initiated by these cytokines, a membrane-enriched preparation from SKW6.4 cells was isolated in a manner that minimized the disruption of membrane protein complexes and then incubated with IL-2, IL-4, or IL-6 in the presence of [gamma-32P]ATP. IL-2, IL-4, and IL-6 stimulated the rapid serine/threonine phosphorylation of 47-, 49-, and 91-kDa proteins. However, in contrast to the 47- and 49-kDa proteins that remained phosphorylated for up to 30 min poststimulation, the 91-kDa protein was rapidly dephosphorylated within 15 min of stimulation. The observation that serine/threonine phosphorylation of the same proteins was stimulated by IL-2, IL-4, and IL-6 suggested that the cytokines activated either different protein kinases with the same substrate specificity or the same protein kinase. In addition, stimulation of intact SKW6.4 cells with either IL-2, IL-4, or IL-6 induced the phosphorylation of two proteins with molecular masses of 45- to 50-kDa and 85 to 90-kDa. Taken together, our data demonstrate that activation of both a serine/threonine kinase and a tyrosine kinase is involved in the IL-2, IL-4, and IL-6-stimulation of IgM secretion by SKW6.4 cells and activation of the same or a similar serine/threonine protein kinase is an early step in the signal transduction pathway used by these cytokines.
Current Progress of RNA Aptamer-Based Therapeutics (2012)

Aptamers are single-stranded nucleic acids that specifically recognize and bind tightly to their cognate targets due to their stable three-dimensional structure. Nucleic acid aptamers have been developed for various applications, including diagnostics, molecular imaging, biomarker discovery, target validation, therapeutics, and drug delivery. Due to their high specificity and binding affinity, aptamers directly block or interrupt the functions of target proteins making them promising therapeutic agents for the treatment of human maladies. Additionally, aptamers that bind to cell surface proteins are well suited for the targeted delivery of other therapeutics, such as conjugated small interfering RNAs (siRNA) that induce RNA interference (RNAi). Thus, aptamer-siRNA chimeras may offer dual-functions, in which the aptamer inhibits a receptor function, while the siRNA internalizes into the cell to target a specific mRNA. This review focuses on the current progress and therapeutic potential of RNA aptamers, including the use of cell-internalizing aptamers as cell-type specific delivery vehicles for targeted RNAi. In particular, we discuss emerging aptamer-based therapeutics that provide unique clinical opportunities for the treatment various cancers and neurological diseases.
Three-Dimensional Vision and Human Motion Analysis (2009)

Click to increase image sizeClick to decrease image sizeKeywords: THREE-DIMENSIONAL VISIONREAL-TIME MODELINGHUMAN MOTION ANALYSIS
Overcoming Time-Dependent Inhibition (TDI) of Cytochrome P450 3A4 (CYP3A4) Resulting from Bioactivation of a Fluoropyrimidine Moiety (2018)

Herein we describe structure-activity relationship (SAR) and metabolite identification (Met-ID) studies that provided insight into the origin of time-dependent inhibition (TDI) of cytochrome P450 3A4 (CYP3A4) by compound 1. Collectively, these efforts revealed that bioactivation of the fluoropyrimidine moiety of 1 led to reactive metabolite formation via oxidative defluorination and was responsible for the observed TDI. We discovered that substitution at both the 4- and 6-positions of the 5-fluoropyrimidine of 1 was necessary to ameliorate this TDI as exemplified by compound 19.
Polyimide-Clay Composite Materials for Space Application (2005)

The introduction of nanometer-sized clay particles into a polyimide matrix has been shown to enhance the physical properties of specific polymer systems. The clay comprises large stacked platelets of the oxides of aluminum and silicon. These sheets have long dimensions on the order of tenths of a micrometer and thicknesses of several nanometers. Homogeneous dispersion of the clay platelets in the polymer matrix is necessary to achieve those enhancements in polymer properties. Natural montmorillonite with the empirical formula Na0.33Mg0.33Al1.67(OH)2(Si4O10) contains exchangeable inorganic cations. The clay lamellae stack together with the positive sodium ions situated between the surfaces of the individual sheets to balance negatively charged oxygen atoms that are on the surfaces of the sheets. These surface charges contribute to strong electrostatic forces which hold the sheets together tightly. Exfoliation can be accomplished only with unusual measures. In preparing clay nanocomposites, we have taken two steps to try to reduce these interlamellar forces in order to promote the separation (exfoliation) of the sheets and the dispersion of the individual clay particles throughout the organic polymer matrix. In the first step, some of the surface Na(+) ions are replaced with Li(+) ions. Unlike sodium cations, the lithium cations migrate into the interior of the lamellae when the system is heated. Their departure from the surface reduces the surface charge and therefore the attractive forces between the sheets. The loss of alkali metal cations from the surface can be measured as the cation exchange capacity (CEC) of the clay. For example, we found that the CEC of montmorillonite clay was reduced by almost two thirds by treating it with lithium ions and heating to 250 C for 24 hr. Lesser heating has a smaller effect on the CEC. X-ray diffraction measurements show that the d-spacing decreased from ca. 1.34 to 0.97 nm, apparently a consequence of a collapse of the clay layers. We observed that the d-spacing can be varied by altering the heat treatment. In the second part of our effort to reduce the interlamellar forces, the remaining inorganic surface cations were replaced by the trimethylphenylammonium ion (TMPA), the biphenyltrimethylammonium ion (BTMA), or the tetraphenylphosphonium ion (TPP).
InGaAs/GaAsSb type-II quantum-well focal plane array with cutoff-wavelength of 2.5 μm (2017)

In the short wavelength infrared (SWIR) region, InGaAs/GaAsSb type-II quantum well absorption structures are proposed as an attractive material for realizing low dark current. Recently QVGA format (array size 320&times;256) focal plane array (FPA) with cutoff-wavelength of 2.35 &mu;m was demonstrated for commercial use by our group. We succeeded in extending cut-off wavelength of FPA consisting of InGaAs/GaAsSb type-II quantum well up to 2.5 &mu;m. The 250-pairs InGaAs/GaAsSb quantum well structure lattice matched to InP substrate was grown by metal organic vapor phase epitaxy (MOVPE). The p-n junction of each pixel was formed by selective zinc diffusion method. Dark current of pixel showed the diffusion current limited mode and slightly better than that of HgCdTe with a same cutoff-wavelength. We present the electrical and optical characteristics of InGaAs/GaAsSb type-II quantum well FPA with cutoff-wavelength of 2.5 &mu;m.
Hadamard transforms on multiply/add architectures (1994)

A new algorithm for computing Hadamard transforms is presented. If n is a power of four, then the new algorithm uses 7/8 n log/sub 2/ n multiply/adds to compute a Hadamard transform of length n.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
CFD in circuit breaker research &amp; development (2011)

The development and optimization of circuit breakers is nowadays strongly influenced by computational fluid dynamics (CFD) simulations. The main reason is that the corresponding experiments are expensive and provide only limited amount of data, usually in integral form. On the other side, CFD allows analyzing the transient behavior of all quantities described in the models. This contribution collects a number of CFD related activities for circuit breaker research and development at ABB Corporate Research. In the simulations reported here, the plasma is treated as a one fluid model, i.e. the molecular processes such as dissociation and recombination are only reflected by pressure and temperature dependent material properties. The paper introduces the CFD model with radiation transport and the coupling to the electro- and magneto-static field equations. The predictive power of these simulations is demonstrated through comparison with results from a small scale test device (mixing of hot gas in a heating volume) and a full breaker (arc voltage and pressure rise).
Sports Program Boundary Detection (2006)

In the recent years, consumer devices that can record broadcast video have become prevalent. Such devices rely on the program guide information about a program start time and end time for recording. However, sports broadcasts can run over the specified time sometimes. In this paper, we propose a framework based on an audio classification framework to correctly detect the end of a sport broadcast so as to enable complete recording of the game. Our experimental results show that the proposed algorithm can detect sports program boundaries with a high accuracy
Effect of confinement on DNA dynamics in microfluidic devices (2003)

The dynamics of dissolved long-chain macromolecules are different in highly confined environments than in bulk solution. A computational method is presented here for detailed prediction of these dynamics, and applied to the behavior of ∼1–100 μm DNA in micron-scale channels. The method is comprised of a self-consistent coarse-grained Langevin description of the polymer dynamics and a numerical solution of the flow generated by the motion of polymer segments. Diffusivity and longest relaxation time show a broad crossover from free-solution to confined behavior centered about the point H≈10Sb, where H is the channel width and Sb is the free-solution chain radius of gyration. In large channels, the diffusivity is similar to that of a sphere diffusing along the centerline of a pore. For highly confined chains (H/Sb≪1), Rouse-type molecular weight scaling is observed for both translational diffusivity and longest relaxation time. In the highly confined region, the scaling of equilibrium length and relaxation time with H/Sb are in good agreement with scaling theories. In agreement with the results of Harden and Doi [J. Phys. Chem. 96, 4046 (1992)], we find that the diffusivity of highly confined chains does not follow the scaling relation predicted by Brochard and de Gennes [J. Chem. Phys. 67, 52 (1977)]; that relationship does not account for the interaction between chain and wall.
A Small-Molecule-Based Approach to Sense Codon-Templated Natural-Unnatural Hybrid Peptides. Selective Silencing and Reassignment of the Sense Codon by Orthogonal Reacylation Stalling at the Single-Codon Level (2005)

In the presence of the stable sulfamoyl analogue of phenylalanyl adenylate (Phe-SA), the UUU/UUC sense codon for phenylalanine (Phe) can be silenced and reassigned to a naphthylalanine (Nap) conjugated to tRNAPhe. We have demonstrated the efficiency and selectivity or orthogonality of the Phe-to-Nap reassignment induced by an "orthogonal reacylation stalling" strategy at the single-codon level in the translation of mRNAs of dihydrofolate reductase and a 24-mer oligopeptide. We used a prokaryotic translation system with an essential preincubation, during which the endogenous precharged phenylalanyl-tRNAPhe undergoes deacylation and the reacylation of the resulting tRNAPhe is stalled by the action of Phe-SA to inhibit the phenylalanyl-tRNA synthetase activity. We discuss the significance of the present small-molecule-based approach to sense-codon templated natural-unnatural peptides.
HIV drug resistance in a community‐randomized trial of universal testing and treatment: HPTN 071 (PopART) (2022)

UTT was not associated with an increase in drug resistance in this cohort. Higher rates of drug resistance and multi-class resistance were observed in non-seroconverters compared to seroconverters.