gebhart/patrepeval huggingface dataset:
Enhanced Nonlinear Optical Activity of Molecules Containing Two D−π−A Chromophores Locked Parallel to Each Other (2008)

A series of H-shaped second-order nonlinear optical (NLO) chromophores with two parallel and nonconjugated D−π−A units have been synthesized, in which a 9,10-dihydroanthracene is employed as molecular backbone. The measurement results of hyper-Rayleigh scattering (HRS) and UV−vis spectra show that the first molecular hyperpolarizability (β) values of H-shaped chromophores are remarkably increased compared with the corresponding mono-D−π−A unit reference compounds (the enhancements per azo D−π−A unit from 1.2 to 3.0 are observed), without causing a large shift of the absorption band to longer wavelength. Therefore, it gives an available way of solving the trade-off between nonlinearity and transparency in designing NLO chromophores. Furthermore, some main-chain fluoro-containing polyimides embedded with the H-shaped chromophores have also been prepared. The elemental investigation results show that the polyimides exhibit a higher macroscopic nonlinear optical coefficient (d33 = 35.0 to ∼70.2 pm/V), good thermal stability (Tg 198 to ∼210 °C, Td 240 to ∼245 °C), and optical transparency (λmax < 400 nm).
The Pervasive Presence of Fluctuating Oxygenation in Tumors (2008)

Tumor hypoxia is a persistent obstacle for traditional therapies in solid tumors. Strategies for mitigating the effects of hypoxic tumor cells have been developed under the assumption that chronically hypoxic tumor cells were the central cause of treatment resistance. In this study, we show that instabilities in tumor oxygenation are a prevalent characteristic of three tumor lines and previous characterization of tumor hypoxia as being primarily diffusion-limited does not accurately portray the tumor microenvironment. Phosphorescence lifetime imaging was used to measure fluctuations in vascular pO(2) in rat fibrosarcomas, 9L gliomas, and R3230 mammary adenocarcinomas grown in dorsal skin-fold window chambers (n = 6 for each tumor type) and imaged every 2.5 minutes for a duration of 60 to 90 minutes. O(2) delivery to tumors is constantly changing in all tumors, resulting in continuous reoxygenation events throughout the tumor. Vascular pO(2) maps show significant spatial heterogeneity at each time point, as well as between time points. The fluctuations in oxygenation occur with a common periodicity within and between tumors, suggesting a common mechanism, but have tumor type-dependent spatial patterns. The widespread presence of fluctuations in tumor oxygenation has broad ranging implications for tumor progression, stress response, and signal transduction, which are altered by oxygenation/reoxygenation events.
Room temperature borylation of arenes and heteroarenes using stoichiometric amounts of pinacolborane catalyzed by iridium complexes in an inert solventElectronic supplementary information (ESI) available: experimental procedures and spectral analyses of products. See http://www.rsc.org/suppdata/cc/b3/b311103b/ (2003)

Aromatic C-H borylation of arenes and heteroarenes using stoichiometric amounts of pinacolborane was catalyzed by an iridium complex generated from 1/2[Ir(OMe)(COD)]2 and 4,4'-di-tert-butyl-2,2'-bipyridine at room temperature in hexane and afforded the corresponding aryl- and heteroarylboronates in high yields with excellent regioselectivities.
Fruit thinning of peach trees (<i>Prunus persica</i>(L.) Batsch.): the effect of paclobutrazol on fruit drop and shoot growth (1987)

SummaryPaclobutrazol (2000 mg l−1) was tested as a fruit thinning agent for cvs Redhaven and Sudanell-1 peach trees. Foliar sprays were applied at three different stages of fruit development: G or petal fall; H or shuck-off; and the beginning of pit-hardening, and compared to trees either hand-thinned or left unthinned. No effect on fruit drop or crop load was observed on Redhaven, but some abscission of fruits occurred on the Sudanell-1 trees treated with paclobutrazol at stages G and H. Shoot growth of both cultivars was inhibited by the two latter applications; this effect was greater in Redhaven, which also showed a reduction in trunk girth increment. In the year after treatments no effect on cropping was observed, but shoot growth was promoted on the trees treated with paclobutrazol in comparison with trees either hand-thinned or left unthinned in the previous year.
Electron states in double-channel back-gated HEMT structures (1993)

Presents the results of self-consistent calculations for the electronic subband structure of double-channel back-gated HEMT structures. This structure is a promising candidate for a velocity modulated transistor in which electrons are switched between high- and low-mobility 2DEGS by applying biases to front and back gates. The calculations identify the important physics for this structure, which uses alloy and ionized impurity scattering to selectively lower the mobility of one of the 2DEGS. The design optimization for this device is discussed.
Selective Destabilization of Short-Lived mRNAs with the Granulocyte-Macrophage Colony-Stimulating Factor AU-Rich 3' Noncoding Region Is Mediated by a Cotranslational Mechanism (1993)

The 3' noncoding region element (AUUUA)n specifically targets many short-lived mRNAs for degradation. Although the mechanism by which this sequence functions is not yet understood, a potential link between facilitated mRNA turnover and translation has been implied by the stabilization of cellular mRNAs in the presence of protein synthesis inhibitors. We therefore directly investigated the role of translation on mRNA stability. We demonstrate that mRNAs which are poorly translated through the introduction of stable secondary structure in the 5' noncoding region are not efficiently targeted for selective destabilization by the (AUUUA)n element. These results suggest that AUUUA-mediated degradation involves either a 5'-->3' exonuclease or is coupled to ongoing translation of the mRNA. To distinguish between these two possibilities, we inserted the poliovirus internal ribosome entry site, which promotes internal ribosome initiation, downstream of the 5' secondary structure. Translation directed by internal ribosome binding was found to fully restore targeted destabilization of AUUUA-containing mRNAs despite the presence of 5' secondary structure. This study therefore demonstrates that selective degradation mediated by the (AUUUA)n element is coupled to ribosome binding or ongoing translation of the mRNA and does not involve 5'-to-3' exonuclease activity.
Phenotypic and Functional Modulation of Normal Human Alveolar Macrophages by Histamine (1994)

Alveolar macrophages (AM) play a regulatory role in asthma. AM from asthmatics are activated, release increased amounts of cytokines, and express higher levels of the low affinity receptor for IgE (Fc epsilon RIIb/CD23b) and receptors for adhesion molecules. The bronchial microenvironment may modulate the phenotypic and functional characteristics of AM. On AM from normal subjects, the effects of histamine were studied on the expression of adhesion molecules (LFA-1, ICAM-1) and CD23b as well as on the release of fibronectin. The expression of LFA-1, ICAM-1, and CD23b was examined by immunocytochemistry using the alkaline phosphatase-anti-alkaline phosphatase technique. The expression of CD23b mRNA was studied by in situ hybridization. The release of fibronectin was measured by enzyme immunoassay. We found that histamine induced in a dose- and time-dependent fashion a significant increase of AM expressing the three membrane markers and a significant increase in the release of fibronectin. The maximum effect of histamine was observed after an incubation of 12 to 24 h and a dose of 1 microM. The histamine effects were specific, since they were significantly inhibited by an H1-blocker, pyrilamine, used at a concentration of 10 microM. The effect of an H2-blocker (ranitidine, concentration of 10 microM) was inconstant. Cycloheximide blocked the histamine effects, suggesting that it requires protein synthesis for its action. This study provides an in vitro model of cellular interaction between mast cells and AM, which might be relevant in the airway inflammation in asthma.
Über die Synthese und Eigenschaften von brückensubstituierten p‐Oligophenylenen. 13. Mitteilung (1963)

Abstract Es wird über die Darstellung von p‐Oligophenylenen berichtet, bei denen Rotationsmöglichkeiten der verknüpften Benzolringe um Biarylbindungen durch Äthyleno‐ oder Äthylidenobrücken blockiert sind. Die Synthesen wurden im wesentlichen von der Fragestellung bestimmt, warum die Löslichkeit von p‐Oligophenylenen durch seitenständige Methylgruppen so stark erhöht wird. An Hand der brückensubstituierten Verbindungen wird eine Arbeitshypothese bestätigt, welche die Wirksamkeit der Seitenketten auf eine Störung der Molekülsymmetrie zurückführt. Es können zwei Asymmetrieeffekte unterschieden werden: der Substituenteneffekt erfaßt dabei den durch die substituierten Gruppen schlechthin bedingten Symmetriemangel, der Rotationseffekt dagegen die durch die innere Molekülbeweglichkeit (Ringrotation) hervorgebrachte Symmetrieabnahme. Bei den methylsubstituierten p‐Oligophenylenen überlagern sich diese beiden Effekte; dadurch werden sehr hohe Löslichkeitswerte erreicht. Es wird gezeigt, daß auch die Löslichkeit der unsubstituierten p‐Oligophenylene in Verbindung mit einem Rotationseffekt diskutiert werden muß. Die Synthese der brückensubstituierten Verbindungen wurde durch homokondensierende, durch cokondensierende und durch gemischte ULLMANN‐Reaktion verwirklicht. Die Äthylenoverbindungen konnten durch Dehydrierung in die Äthylidenoderivate umgewandelt werden.
Chemistry of polymer-bound o-benzyne. Frequency of encounter between substituents on crosslinked polystyrenes (1979)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry of polymer-bound o-benzyne. Frequency of encounter between substituents on crosslinked polystyrenesStephen Mazur and P. JayalekshmyCite this: J. Am. Chem. Soc. 1979, 101, 3, 677–683Publication Date (Print):January 1, 1979Publication History Published online1 May 2002Published inissue 1 January 1979https://pubs.acs.org/doi/10.1021/ja00497a032https://doi.org/10.1021/ja00497a032research-articleACS PublicationsRequest reuse permissionsArticle Views596Altmetric-Citations126LEARN 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
Anti- and Prooxidant Activity of Water Soluble Components of Some Common Diet Vegetables and the Effect of Thermal Treatment (1998)

The pro-antioxidant activity of carrot, cauliflower, celery, eggplant, garlic, mushroom, onion, white cabbage, white potato, tomato, yellow bell pepper, and zucchini was investigated. Juices obtained by centrifugation of vegetables were treated at different temperatures (2, 25, 102 °C) and assessed for antioxidant activity (AA) using a model system β-carotene−linoleic acid. Antioxidant activity of all vegetable juices showed a linear correlation with time. The equations of all straight lines obtained showed positive slope values indicating either an increase in antioxidant activity or a decrease in prooxidant activity during the reaction. Negative intercept values were found when the juices showed prooxidant activity at least during the first phase of the reaction. Mushroom and white cabbage always showed more than 80% AA, while cauliflower, celery, and eggplant showed such high AA only after boiling. Tomato and yellow bell pepper were always prooxidant. Cluster analysis allowed the vegetables to be divided into five groups according to their anti- and prooxidant behavior as a function of thermal treatment and reaction time. Vegetable juice components were separated on a Bakerbond C18 solid-phase extraction cartridge according to their polarity, and the AA of the bound and unbound fractions of each vegetable was also tested. Keywords: Vegetables; lipid peroxidation; antioxidants; prooxidant
Synthesis and properties of unsymmetrical aryl glucosyl disulfides: models for a new class of cleavable nonionic detergents (1980)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and properties of unsymmetrical aryl glucosyl disulfides: models for a new class of cleavable nonionic detergentsJohn Cuomo, James H. Merrifield, and John F. W. KeanaCite this: J. Org. Chem. 1980, 45, 21, 4216–4219Publication Date (Print):October 1, 1980Publication History Published online1 May 2002Published inissue 1 October 1980https://pubs.acs.org/doi/10.1021/jo01309a030https://doi.org/10.1021/jo01309a030research-articleACS PublicationsRequest reuse permissionsArticle Views197Altmetric-Citations26LEARN 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
Role of SspA in the density-dependent expression of the transcriptional activator AarP in Providencia stuartii (2001)

The AarP protein in Providencia stuartii encodes a small transcriptional activator which activates the chromosomal aminoglycoside acetyltransferase aac(2 ′)-Ia gene. In addition, AarP activates genes involved in a multiple antibiotic resistance (Mar) phenotype. Expression of an aarP–lacZ fusion increased in a density-dependent manner and reached peak levels at stationary phase. The expression of an aarP–lacZ fusion could be prematurely activated in cells at early to mid-exponential phase by the addition of spent culture supernatants from stationary phase cultures or by ethyl acetate extracts of these supernatants. Nutrient starvation had a negligible effect on aarP expression. In a search for mutations that block aarP activation at stationary phase, a mini-Tn5Cm insertion has been identified within a gene whose product was 77% identical to SspA, a regulatory protein involved in stationary phase gene expression and virulence. An unmarked sspA null allele (sspA2) was created by allelic replacement to further examine the role of sspA in P. stuartii. The sspA2 allele resulted in substantial decrease in aarP mRNA accumulation at various phases of growth. Furthermore, in an sspA mutant background, the aarP–lacZ fusion was no longer activated by an extracellular signal.
The Calcium Channel Blockers, 1,4-Dihydropyridines, Are Substrates of the Multidrug Resistance-Linked ABC Drug Transporter, ABCG2 (2006)

The human ATP-binding cassette transporter, ABCG2, confers resistance to multiple chemotherapeutic agents and also affects the bioavailability of different drugs. [(125)I]Iodoarylazidoprazosin (IAAP) and [(3)H]azidopine were used for photoaffinity labeling of ABCG2 in this study. We show here for the first time that both of these photoaffinity analogues are transport substrates for ABCG2 and that [(3)H]azidopine can also be used to photolabel both wild-type R482-ABCG2 and mutant T482-ABCG2. We further used these assays to screen for potential substrates or modulators of ABCG2 and observed that 1,4-dihydropyridines such as nicardipine and nifedipine, which are clinically used as antihypertensive agents, inhibited the photolabeling of ABCG2 with [(125)I]IAAP and [(3)H]azidopine as well as the transport of these photoaffinity analogues by ABCG2. Furthermore, [(3)H]nitrendipine and bodipy-Fl-dihydropyridine accumulation assays showed that these compounds are transported by ABCG2. These dihydropyridines also inhibited the efflux of the known ABCG2 substrates, mitoxantrone and pheophorbide-a, from ABCG2-overexpressing cells, and nicardipine was more potent in inhibiting this transport. Both nicardipine and nifedipine stimulated the ATPase activity of ABCG2, and the nifedipine-stimulated activity was inhibited by fumitremorgin C, suggesting that these agents might interact at the same site on the transporter. In addition, nontoxic concentrations of dihydropyridines increased the sensitivity of ABCG2-expressing cells to mitoxantrone by 3-5-fold. In aggregate, results from the photoaffinity labeling and efflux assays using [(125)I]IAAP and [(3)H]azidopine demonstrate that 1,4-dihydropyridines are substrates of ABCG2 and that these photolabels can be used to screen new substrates and/or inhibitors of this transporter.
A qualitative approach to the evaluation of a cardiac education follow-up program. (1995)

The purpose of this study was to evaluate a Cardiac Education Follow-Up Program from the consumer's perspective. Nine cardiac patients between the ages of 51 and 70 participated. All had diagnoses of myocardial infarction and had taken the Program within the previous month. Patton's (1986) utilization-focused approach to evaluation provided the conceptual orientation and the Davis Patient Interview Guide (DPIG) was used for data collection. Results indicated that four aspects of the Program were of predominant interest/concern: information; support; the cardiologist's session; and the room in which the class was offered. Recommendations for program modification, using the results of the consumer's evaluation, are identified.
Time series for currency exchange rate of the Brazilian Real (2002)

In our global village the currency exchange rate of a country is considered by international investors as an important yardstick for measuring the health of its economy. In the paper an analysis is made of the Brazilian Real using three different methodologies: the Box-Jenkins or SARIMA; exponential smoothing; and a backpropagation neural network trained by the Levenberg-Marquardt algorithm. Not surprisingly, our study indicates that given the same input data different paradigms yield different results. However, presumably due to the intervention of the Central Bank, the time series exhibits quasiperiodic behaviour. Extrapolations are made into the future. Possible implications are discussed. Our methodology can be applied to any currency extant.
Availability of amino acids supplied by constant intravenous infusion of synthetic dipeptides in healthy man (1989)

1. A commercial amino acid solution supplemented with two synthetic dipeptides, L-alanyl-L-glutamine (Ala-Gln) and glycyl-L-tyrosine (Gly-Tyr), or alternatively with isonitrogenous amounts of free alanine and glycine has been continuously infused over 4 h in six apparently healthy volunteers. 2. The infusion of the solutions was not accompanied by any side effects and the volunteers reported no complaints. 3. Infusion of the alanine- and glycine-supplemented control solution resulted in an increase of the concentration of these amino acids, while no appreciable change in free glutamine concentration was observed and free tyrosine revealed a steady decrease throughout the infusion. 4. Infusion of the peptide-supplemented solution resulted in a prompt equimolar liberation of the constituent free amino acids (glutamine, alanine, tyrosine and glycine), approaching steady state after about 30 min infusion, while only trace but stable concentrations of the two dipeptides were measured throughout the infusion. No peptides were detectable in urine. The findings suggest a nearly quantitative extracellular hydrolysis of the infused dipeptides and indicate a subsequent utilization of the liberated free amino acids. 5. The estimated metabolic clearance rates and total body plasma clearances were very similar for the two dipeptides (Ala-Gln 35.9 +/- 9.5 ml min-1 kg-1 and 2.9 +/- 0.9 l/min, respectively; Gly-Tyr 33.7 +/- 9.5 ml min-1 kg-1 and 2.7 +/- 0.9 l/min, respectively); thus there is little difference in the metabolic handling of these dipeptides.(ABSTRACT TRUNCATED AT 250 WORDS)
Cost-Effectiveness Analysis of Enhancing the Pavement-Related Information Systems at the Texas Department of Transportation (2003)

Research Project 0-4186 entitled, “Cradle-to-Grave Monitoring of Pavements and Pavement Management Information System (PMIS) Functionality Enhancement Planning,” is intended to develop strategic plans for integrating the pavement-related databases at the Texas Department of Transportation (TxDOT) and enhancing the decision support functions in the PMIS. To integrate pavement-related data, a new information system is proposed. This report presents a comprehensive cost-effectiveness analysis as a part of the feasibility study for developing the proposed information system. The concept of information system integration is outlined first, followed by a brief review of the current pavement-related databases and a discussion of the conceptual framework for the proposed information system. Then, potential methods for conducting cost-benefit analysis are reviewed. Using the findings from the review, a framework for cost-effectiveness analysis is established with an eight-step process. Using the eight-step process, the cost-effectiveness analysis for the proposed information system is conducted. Sensitivity analyses are also performed to examine the relative impact of the selected input parameters on the output of the cost-effectiveness analysis. Based on the analysis results from the capital budgeting models, it is evident that the investment on developing a new information system to support the pavement engineering and management activities at TxDOT is fully justified.
Determination of Acidity Constants of Perfluoroalkanoic Acids (2001)

Abstract Acidity constants (Ka) of perfluoroalkanoic acids were determined by pH titration and by electric conductivity for shorter alkanoic acids (C1 to C5) with 1 to 5 carbon atoms in the alkyl chain. The acidity constants obtained by the two methods are in good agreement. They increase from C1 (ethanoic) to C3 (butanoic acid) and then decrease from C3 to C5 (hexanoic acid) with increasing alkyl chain length. An abrupt decrease in the Ka value for the C5 acid occurred; the attempt to explain this in terms of viscosity of the solutions did not succeeded. The decrease in the Ka values with increasing alkyl chain length was substantiated by the values for C9 (decanoic) to C11 (dodecanoic) acids, which were determined from the solubility change with the solution pH. For the intermediate alkanoic acids (C6 to C8), the Ka values could not be determined precisely by these methods due to the extreme difficulty in separating the colloidal acid particles from the aqueous phase, because the particles have an emulsifying action of their own.