gebhart/patrepeval huggingface dataset:
Polystyrene-block-poly(butyl acrylate) and polystyrene-block-poly[(butyl acrylate)-co-styrene] block copolymers prepared via controlled free-radical miniemulsion polymerization using degenerative iodine transfer (2000)

Polystyrene-block-poly(butyl acrylate) and polystyrene-block-poly[(butyl acrylate)-co-styrene] block copolymers were prepared in an aqueous dispersed system via controlled free-radical miniemulsion polymerization using degenerative iodine transfer. The first step is batch miniemulsion polymerization of styrene in the presence of C6F13I as transfer agent. The second step consists of the addition of butyl acrylate to this seed latex, either in one shot or continuously. The addition was started before the consumption of styrene was complete in order to perform a copolymerization reaction able to moderate the rate of propagation in the butyl acrylate polymerization step and, therefore, to favor the transfer reaction. Kinetics of polymerization and control of the molar masses were examined according to the experimental conditions and particularly to the rate of butyl acrylate addition. The formed block copolymers were analyzed by size exclusion chromatography (SEC), differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR).
New Insights into the Evolutionary Links Relating to the 3-Deoxy-D-arabino-heptulosonate 7-Phosphate Synthase Subfamilies (2005)

Bacterial 3-deoxy-d-arabino-heptulosonate 7-phosphate synthases (DAHPSs) have been divided into either of two classes (Class I/Class II) or subfamilies (AroAI(alpha)/AroAI(beta)). Our investigation into the biochemical properties of the unique bifunctional DAHPS from Bacillus subtilis provides new insight into the evolutionary link among DAHPS subfamilies. In the present study, the DAHPS (aroA) and chorismate mutase (aroQ) activities of B. subtilis DAHPS are separated by domain truncation. Detailed enzymatic studies with the full-length wild-type protein and the truncated domains led to our hypothesis that the aroQ domain was fused to the N terminus of aroA in B. subtilis during evolution for the purpose of feedback regulation and not for the creation of a bona fide bifunctional enzyme. In addition, examination of aroA and aroQ fusion proteins from Porphyromonas gingivalis, in which the aroQ domain is fused to the C terminus of aroA, further supports the hypothesis. These results, along with sequence structure analysis of the DAHPS families suggest that "feedback regulation" may indeed be the evolutionary link between the two classes/subfamilies. It is likely that DAHPSs evolved from a primitive unregulated member of the AroAI(beta) subfamily. During evolution, some members of the AroAI(beta) subfamily remained unregulated, whereas other members acquired an extra domain for feedback regulation. The AroAI(alpha) subfamilies, however, evolved in a more complex manner to acquire insertions/extensions in the (beta/alpha)(8) barrel to function as regulatory elements.
TNP-ATP and TNP-ADP as Probes of the Nucleotide Binding Site of CheA, the Histidine Protein Kinase in the Chemotaxis Signal Transduction Pathway of Escherichia coli (1998)

The interaction of CheA with ATP has important consequences in the chemotaxis signal transduction pathway of Escherichia coli. This interaction results in autophosphorylation of CheA, a histidine protein kinase. Autophosphorylation of CheA sets in motion a chain of biochemical events that enables the chemotaxis receptor proteins to communicate with the flagellar motors. As a result of this communication, CheA allows the receptors to control the cell swimming pattern in response to gradients of attractant and repellent chemicals. To probe CheA interactions with ATP, we investigated the interaction of CheA with the fluorescent nucleotide analogues TNP-ATP [2'(3')-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate] and TNP-ADP. Spectroscopic studies indicated that CheA bound TNP-ATP and TNP-ADP with high affinity (micromolar Kd values) and caused a marked enhancement of the fluorescence of the TNP moiety of these modified nucleotides. Analysis of titration experiments indicated a binding stoichiometry of two molecules of TNP-ATP (TNP-ADP) per CheA dimer and suggested that the two binding sites on the CheA dimer operate independently. Binding of TNP-ATP to CheA was inhibited by ATP, and analysis of this inhibition indicated that the CheA dimer binds 2 molecules of ATP. Competition experiments also indicated that CheA binds TNP-ATP considerably more tightly than it binds unmodified ATP. Binding of TNP-ADP to CheA was inhibited by ADP in a similar manner. TNP-ATP was not a substrate for CheA and served as a potent inhibitor of CheA autophosphorylation (Ki < 1 microM). The glycine-rich regions (G1 and G2) of CheA and other histidine protein kinases have been presumed to play important roles in ATP binding and/or catalysis of CheA autophosphorylation, although few experimental tests of these functional assignments have been made. Here, we demonstrate that a CheA mutant protein with Gly-->Ala substitutions in G1 and G2 has a markedly reduced affinity for ATP and ADP, as measured by Hummel-Dreyer chromatography. This mutant protein also bound TNP-ATP and TNP-ADP very poorly and had no detectable autokinase activity. Surprisingly, a distinct single-site substitution in G2 (Gly470-->Lys) had no observable effect on the affinity of CheA for ATP and ADP, despite the fact that it rendered CheA completely inactive as an autokinase. This mutant protein also bound TNP-ATP and TNP-ADP with affinities and stoichiometries that were indistinguishable from those observed with wild-type CheA. These results provide some preliminary insight into the possible functional roles of G1 and G2, and they suggest that TNP-nucleotides are useful tools for exploring the effects of additional mutations on the active site of CheA.
MICROENCAPSULATION TECHNOLOGY: A REVIEW (2010)

The development of new functional foods requires technologies for incorporating health promoting&#13;\ningredients into food without reducing their bioavailability or functionality. In many cases, microencapsulation&#13;\ncan provide the necessary protection for these compounds. Microcapsules offer food processors a means to&#13;\nprotect sensitive food components, ensure protection against nutritional loss, utilize sensitive ingredients,&#13;\nincorporate unusual or time-release mechanisms into the formulation, mask or preserve flavors/aromas and&#13;\ntransform liquids into easy to handle solid ingredients. Various techniques cab be employed to form&#13;\nmicrocapsules, including spray drying, spray chilling or spray cooling, extrusion coating, fluidized-bed coating,&#13;\nliposomal entrapment, lyophilization, coacervation, centrifugal suspension separation, cocrystallization and&#13;\ninclusion complexation. This article describes the recent and advanced techniques of microencapsulation.&#13;\nControlled release of food ingredients at the right place and the right time is a key functionality that can be&#13;\nprovided by microencapsulation. Timely and targeted release improves the effectiveness of food additives,&#13;\nbroadens the application range of food ingredients, and ensures optimal dosage, thereby improving the cost&#13;\neffectiveness for the food manufacturer
Therapy with Natalizumab Is Associated with High JCV Sero-Conversion and Rising JCV Index Values (P2.064) (2016)

Objective: Aim of the study was to analyze JCV serology in natalizumab-treated patients over time and assess, whether they are influenced by natalizumab treatment. Background: JCV serology is used for PML risk stratification during treatment with natalizumab. JCV-seronegative patients have a virtually non-existent PML risk, but patients do convert to JCV seropositivity with age. Seroconversion by age might be enhanced by treatment with natalizumab. Methods: German (n=1921; 525 longitudinally) and French (n=1259; 711 longitudinally) patients were assessed for JCV serology alongside their therapy with natalizumab. Results: JCV sero-status changed in 69 of 525 longitudinally followed German patients (13.1[percnt]) over 14.8 months. Sero-conversion according to sero-status was seen in 43 of 339 initially JCV- German patients (12.7[percnt] in 14.8 months; 10.3[percnt] per year) and 41 of 243 initially JCV- French patients (16.9[percnt] in 24 months; 8.5[percnt] per year). JCV index values could be reproduced (R2=0.89) with the caveat of 8 of 50 samples (16[percnt]) being set into different risk categories between two assessments. Index values of JCV+ patients rose over time (p=0.009), but not due to aging. Treatment with natalizumab was associated with a 15.9[percnt] rise of JCV index values in 14.8 months (12.9[percnt] per year). Conclusions: JCV sero-conversion and -index values may be influenced by the treatment with natalizumab. It is, therefore, important to monitor patients’ JCV serology, but also incorporate additional risk factors into the PML risk stratification. Study supported by: the Deutsche Forschungsgesellschaft (DFG) Grant CRC128 to NS and HW, the PML consortium to NS and HW, the Kompetenznetz Multiple Sklerose (Competence Network for Multiple Sclerosis) funded by the Federal Ministry of Education and Research (FKZ 01GI1308B 01GI0907) to HW, French Ministry of Health (PHRC 2008-005906-38, ARSEP (French MS society grant 2009 and 2011) to DB, and the EU (BEST-MS, FP7, 305477) to DB and HW.
Preparation of the 4-Carboethoxy-3-trifluoromethylcyclohex-2-enone (1991)

Abstract The 4-carboethoxy-3-trifluoromethylcyclohex-2-enone was prepared in 2 steps from methylvinylketone and ethyl trifluoroacetoacetate.
Cyclosporin A, the cyclophilin class of peptidylprolyl isomerases, and blockade of T cell signal transduction. (1992)

Cyclosporin A, the major immunosuppressive drug in transplantation, and the more potent therapeutic drug candidate, FK506, have led to the discovery of two superfamilies of immunosuppressant binding proteins, the cyclophilins and the FK binding proteins. These proteins, enzymes with high kcat values for isomerization of X-Pro bonds in peptides and protein substrates, are distributed in all cell compartments where protein folding normally occurs. It is likely that they play major roles in the protein folding and protein trafficking in the cell. It is also likely that they have been suborned in T cells by the immunosuppressant drugs that are potent pseudosubstrate ligands that selectively block the signal transduction cascade. The discovery of the inhibition of protein phosphatase 2B (calcineurin) by the drug-immunophilin complex (CsA-CyP or FK506-FKBP) provides evidence for a specific downstream target of the drug-immunophilin complexes and may prompt a search for endogenous ligands of cyclophilin and FKBP that may effect signal transduction regulation. The molecular insights gained over a short time in this area have been remarkable; they promise to elucidate the steps in T cell activation and delineate new targets for immunosuppressive therapy.
High-spatial-frequency binary and multilevel stairstep gratings: polarization-selective mirrors and broadband antireflection surfaces (1992)

High-spatial-frequency, surface-relief binary gratings have been shown to have diffraction properties that are similar to homogeneous layers of equivalent refractive indices, which depend on the grating characteristics, angle of incidence, and polarization. Thus these gratings in the long-wavelength limit could be used as equivalent thin-film coatings. Because of their polarization discrimination these gratings can function as polarization-selective mirrors. A procedure for designing these gratings to be antireflective for one polarization (TE or TM) and to maximize their reflectivity for the orthogonal polarization (TM or TE) is presented. Multilevel stairstep gratings can similarly exhibit characteristics that resemble those of multilayer antireflection coatings (quarter-wave impedance transformers), thus permitting a broader wavelength bandpass. A systematic procedure for designing multilevel stairstepgratings to operate as multilayer thin-film antireflection surfaces is presented. These design methods are valid for both TE and TM polarizations and for any angle of incidence. Example designs are presented, and the rigorous coupled-wave diffraction analysis is used to evaluate the performance of these gratings as functions of the ratio of their period to the incident wavelength. Comparisons are included with homogeneous layers that are equivalent to the gratings in the long-wavelength limit.
Bites of Brown Recluse Spiders and Suspected Necrotic Arachnidism (2005)

Although much has been published about the pathophysiology and treatment of necrotic spider bites, therapeutic interventions continue without evidence-based justification.
Inhibition of binding of rat IgE to rat mast cells by synthetic IgE peptides (1987)

Seven synthetic peptides corresponding to amino acid sequences located within various surface regions of the CH3 and CH4 domains of rat IgE were tested for their capacity to compete with intact rat IgE for binding sites on mast cells. Peptides representing rat IgE sequences 414-428 (P129), 459-472 (P124), 491-503 (P128) and 542-557 (P123) inhibited the binding of 125I-labeled rat IgE to mast cells by between 25-50% at concentrations between 10(-5)-10(-4) M. Three other rat IgE sequences, 378-396 (P130), 522-535 (P122) and 560-571 (P131), and three non-IgE peptides demonstrated no inhibitory activity. On a molar basis, the most active peptide, P129, was approximately 1000-times less active than native rat IgE. Furthermore, extensive washing of cells incubated with this peptide did not reduce its ability to inhibit the subsequent binding of 125I-labeled rat IgE. These results suggest that residues within sequences 414-428, 459-473, 491-503 and 542-557 may contribute towards the mast cell receptor binding site on rat IgE.
Engineered Cpf1 variants with altered PAM specificities (2017)

The RNA-guided endonuclease Cpf1 is a promising tool for genome editing in eukaryotic cells. However, the utility of the commonly used Acidaminococcus sp. BV3L6 Cpf1 (AsCpf1) and Lachnospiraceae bacterium ND2006 Cpf1 (LbCpf1) is limited by their requirement of a TTTV protospacer adjacent motif (PAM) in the DNA substrate. To address this limitation, we performed a structure-guided mutagenesis screen to increase the targeting range of Cpf1. We engineered two AsCpf1 variants carrying the mutations S542R/K607R and S542R/K548V/N552R, which recognize TYCV and TATV PAMs, respectively, with enhanced activities in vitro and in human cells. Genome-wide assessment of off-target activity using BLISS indicated that these variants retain high DNA-targeting specificity, which we further improved by introducing an additional non-PAM-interacting mutation. Introducing the identified PAM-interacting mutations at their corresponding positions in LbCpf1 similarly altered its PAM specificity. Together, these variants increase the targeting range of Cpf1 by approximately threefold in human coding sequences to one cleavage site per ∼11 bp.
Oxazolines. XX. Synthesis of achiral and chiral thiiranes and olefins by reaction of carbonyl compounds with 2-(alkylthio)-2-oxazolines (1976)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOxazolines. XX. Synthesis of achiral and chiral thiiranes and olefins by reaction of carbonyl compounds with 2-(alkylthio)-2-oxazolinesA. I. Meyers and Michael E. FordCite this: J. Org. Chem. 1976, 41, 10, 1735–1742Publication Date (Print):May 1, 1976Publication History Published online1 May 2002Published inissue 1 May 1976https://pubs.acs.org/doi/10.1021/jo00872a015https://doi.org/10.1021/jo00872a015research-articleACS PublicationsRequest reuse permissionsArticle Views556Altmetric-Citations77LEARN 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
Characterization and sequencing of the active site of 1-aminocyclopropane-1-carboxylate synthase. (1990)

The pyridoxal phosphate (PLP)-dependent 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (S-adenosyl-L-methionine methylthioadenosine-lyase, EC 4.4.1.14), the key enzyme in ethylene biosynthesis, is inactivated by its substrate S-adenosylmethionine (AdoMet). Apple ACC synthase was purified with an immunoaffinity gel, and its active site was probed with NaB3H4 or Ado[14C]Met. HPLC separation of the trypsin digest yielded a single radioactive peptide. Peptide sequencing of both 3H- and 14C-labeled peptides revealed a common dodecapeptide of Ser-Leu-Ser-Xaa-Asp-Leu-Gly-Leu-Pro-Gly-Phe-Arg, where Xaa was the modified, radioactive residue in each case. Acid hydrolysis of the 3H-labeled enzyme released radioactive N-pyridoxyllysine, indicating that the active-site peptide contained lysine at position 4. Mass spectrometry of the 14C-labeled peptide indicated a protonated molecular ion at m/z 1390.6, from which the mass of Xaa was calculated to be 229, a number that is equivalent to the mass of a lysine residue alkylated by the 2-aminobutyrate portion of AdoMet, as we previously proposed. These results indicate that the same active-site lysine binds the PLP and convalently links to the 2-aminobutyrate portion of AdoMet during inactivation. The active site of tomato ACC synthase was probed in the same manner with Ado[14C]Met. Sequencing of the tomato active-site peptide revealed two highly conserved dodecapeptides; the minor peptide possessed a sequence identical to that of the apple enzyme, whereas the major peptide differed from the minor peptide in that methionine replaced leucine at position 6.
Security and fault-tolerance in distributed systems: an actor-based approach (2002)

The inherent complexity of real-world distributed applications makes developing and maintaining software for these systems difficult and error-prone. We describe an actor-based meta-level model to address the complexity of distributed applications. Specifically, meta-level framework allow code implementing different design concerns to be factored into separate modules-thus enabling the separate development and modification of code for different non-functional requirements such as security and fault-tolerance. This paper reviews current research based on the model and outlines some research directions.
Tissue-Specific Expression of the Rat Growth Hormone Gene Is Due to the Interaction of Multiple Promoter, Not Enhancer, Elements (1990)

Expression of the rat growth hormone (rGH) gene is highly tissue-specific, being limited to a subset of cells in the anterior pituitary. DNA sequences within 237 bp of the transcription start site of the rGH gene play a major role in directing the expression of this gene in the pituitary. Transfection studies in cultured rat pituitary (GC) cells demonstrate that optimal expression of rGH requires the binding of at least two non-tissue-specific factors whose contribution to rGH expression is dependent on the binding of the pituitary-specific factor, Pit-1. Although the segment of DNA containing the elements to which these factors bind can direct pituitary-specific expression of a gene lacking upstream promoter elements, it cannot confer stimulation to either a heterologous or homologous promoter when placed downstream from the coding sequences. These results suggest that expression of the rGH gene exclusively in the pituitary is due to the activity of a tissue-specific promoter element, not an enhancer.
Protein rib: a novel group B streptococcal cell surface protein that confers protective immunity and is expressed by most strains causing invasive infections. (1993)

The group B Streptococcus, an important cause of invasive infections in the neonate, is classified into four major serotypes (Ia, Ib, II, and III) based on the structure of the polysaccharide capsule. Since the capsule is a known virulence factor, it has been extensively studied, in particular in type III strains, which cause the majority of invasive infections. Two cell surface proteins, alpha and beta, have also been studied in detail since they confer protective immunity, but these proteins are usually not expressed by type III strains. We describe here a cell surface protein, designated protein Rib (resistance to proteases, immunity, group B), that confers protective immunity and is expressed by most strains of type III. Protein Rib was first identified as a distinct 95-kD protein in extracts of a type III strain, and was purified to homogeneity from that strain. Rabbit antiserum to protein Rib was used to demonstrate that it is expressed on the cell surface of 31 out of 33 type III strains, but only on 1 out of 25 strains representing the other three serotypes. Mouse protection tests showed that antiserum to protein Rib protects against lethal infection with three different strains expressing this antigen, including a strain representing a recently identified high virulence type III clone. Protein Rib is immunologically unrelated to the alpha and beta proteins, but shares several features with the alpha protein. Most importantly, the NH2-terminal amino acid sequences of the Rib and alpha proteins are identical at 6 out of 12 positions. In addition, both protein Rib and the alpha protein are relatively resistant to trypsin (and Rib is also resistant to pepsin) and both proteins vary greatly in size between different clinical isolates. Finally, both protein Rib and the alpha protein exhibit a regular ladderlike pattern in immunoblotting experiments, which may reflect a repetitive structure. Taken together, these data suggest that the Rib and alpha proteins are members of a family of proteins with related structure and function. Since protein Rib confers protective immunity, it may be valuable for the development of a protein vaccine against the group B Streptococcus, an encapsulated bacterium.
Laboratory Techniques in Electroanalytical Chemistry, Revised and Expanded (2018)

An overview fundamental concepts of analytical electrochemistry large-amplitude controlled-potential techniques large-amplitude controlled-current techniques small-amplitude and related controlled-potential techniques introduction to analog instrumentation overcoming solution resistance with stability and grace in potentiostatic circuits conductivity and conductometry electrochemical cells carbon electrodes film electrodes microelectrodes chemically modified electrodes mercury electrodes solvents and supporting electrolytes electrochemial studies at reduced temperature electroanalytical chemistry in molten salts vacuum line techniques electrochemistry in the dry box digital simulation of electrochemical phenomena evaluation of mechanisms of transition metal complexes electrochemical preconcentration controlled-current coulometry application of electrochemistry to pharmaceutical analysis electrochemical detection in liquid chromatography and capillary electrophoresis photonic electrochemistry principles and techniques of electrochemical-electron paramagnetic resonance experiments.