gebhart/patrepeval huggingface dataset:
Enantiodivergent Biosynthesis of the Dimeric Sphingolipid Oceanapiside from the Marine Sponge <i>Oceanapia phillipensis</i>. Determination of Remote Stereochemistry (2000)

The absolute stereochemistry of oceanapiside, an antifungal α,ω-bis-aminohydroxylipid with four stereogenic centers from the marine sponge Oceanapia phillipensis Dendy, 1895, has been obtained as 2S,3R,26R,27R from development and application of a general CD method based on superposition of additive exciton couplings in perbenzoyl derivatives of bis-amino alcohols. The method allows simultaneous determination of the local relative configuration at each of the termini of the long chain bis-aminolipid and also relates the absolute configuration of the two remote termini. Oceanapiside contains erythro and threo relative configurations at C1,2 and C26,27, respectively, but opposite absolute configurations at the amino substituted carbons C2 and C27 which implies an enantiodivergent biogenesis formally derived from both d- and l-amino acids.
Pyroelectric energy conversion: Optimization principles (2008)

In the framework of microgenerators, we present in this paper the key points for energy harvesting from temperature using ferroelectric materials. Thermoelectric devices profit from temperature spatial gradients, whereas ferroelectric materials require temporal fluctuation of temperature, thus leading to different applications targets. Ferroelectric materials may harvest perfectly the available thermal energy whatever the materials properties (limited by Carnot conversion efficiency) whereas thermoelectric material's efficiency is limited by materials properties (ZT figure of merit). However, it is shown that the necessary electric fields for Carnot cycles are far beyond the breakdown limit of bulk ferroelectric materials. Thin films may be an excellent solution for rising up to ultra-high electric fields and outstanding efficiency. Different thermodynamic cycles are presented in the paper: principles, advantages, and drawbacks. Using the Carnot cycle, the harvested energy would be independent of materials properties. However, using more realistic cycles, the energy conversion effectiveness remains dependent on the materials properties as discussed in the paper. A particular coupling factor is defined to quantify and check the effectiveness of pyroelectric energy harvesting. It is defined similarly to an electromechanical coupling factor as k2=p2theta0/(epsilontheta33cE), where p, theta0, epsilontheta33, cE are pyroelectric coefficient, maximum working temperature, dielectric permittivity, and specific heat, respectively. The importance of the electrothermal coupling factor is shown and discussed as an energy harvesting figure of merit. It gives the effectiveness of all techniques of energy harvesting (except the Carnot cycle). It is finally shown that we could reach very high efficiency using 1110.75Pb(Mg1/3Nb2/3)-0.25PbTiO3 single crystals and synchronized switch harvesting on inductor (almost 50% of Carnot efficiency). Finally, practical implementation key points of pyroelectric energy harvesting are presented showing that the different thermodynamic cycles are feasible and potentially effective, even compared to thermoelectric devices.
Tradeoff in Rule Induction for Semantic Query Optimization (1997)

Semantic query optimization (SQO) is a promising approach to the optimization of increasingly complex query plans in global information systems. The idea of SQO is to use semantic rules about data to reformulate a query into an equivalent but less expensive one. Since it is difficult to encode required semantic rules, a complete SQO system also includes a rule induction system and a rule maintainer. To maximize the net utility of learning, a rule induction system needs to learn those rules that are effective in reducing the query execution cost while robust against data changes to minimize the rule maintenance cost. This paper focuses on this tradeoff between effectiveness and robustness in the rule induction for SQO. The solution is to explicitly estimate the degree of the robustness of rules. The system can use the estimated robustness to make decisions to guide rule construction, guide rule repair, and control the size of a rule set. This paper also briefly reviews how robustness ca...
Growth Hormone Receptor Blockade Inhibits Growth Hormone-Induced Chemoresistance by Restoring Cytotoxic-Induced Apoptosis in Breast Cancer Cells Independently of Estrogen Receptor Expression (2012)

In human BC cell lines, GH directly promotes resistance to apoptosis induced by chemotherapeutic drugs independently of ER expression by modulating JNK, further broadening the concept that GH excess may hamper cytotoxic BC treatment. These findings support the hypothesis that blocking GH receptor may be viewed as a potential new therapeutic approach to overcome chemoresistance, especially in ER-negative BC.
Caldolase, a chelator-insensitive extracellular serine proteinase from a <i>Thermus</i> spp (1989)

An extracellular alkaline serine proteinase from Thermus strain ToK3 was isolated and purified to homogeneity by (NH4)2SO4 precipitation followed by ion-exchange chromatography on DEAE-cellulose and QAE-Sephadex, affinity chromatography on N alpha-benzyloxycarbonyl-D-phenylalanyl-triethylenetetraminyl-Sepha rose 4B and gel-filtration chromatography on Sephadex G-75. The purified enzyme had a pI of 8.9 and an Mr determined by gel-permeation chromatography of 25,000. The specific activity was about 37,700 proteolytic units/mg with casein as substrate, and the pH optimum was 9.5. Proteolytic activity was inhibited by low concentrations of di-isopropyl phosphorofluoridate and phenylmethanesulphonyl fluoride, but was unaffected by EDTA, EGTA, o-phenanthroline, N-ethyl-5-phenylisoxazolium-3'-sulphonate, N alpha-p-tosyl-L-phenylalanylchloromethane, N alpha-p-tosyl-L-lysylchloromethane, trypsin inhibitors and pepstatin A. The enzyme contained approx. 10% carbohydrate and four disulphide bonds. No Ca2+, Zn2+ or free thiol groups were detected. It hydrolysed several native and dye-linked proteins and synthetic chromogenic peptides and esters. The enzyme was very thermostable (half-life values were 840 min at 80 degrees C, 45 min at 90 degrees C and 5 min at 100 degrees C). The enzyme was unstable at low ionic strength: after 60 min at 75 degrees C in 0.1 M-Tris/acetate buffer, pH 8, only 20% activity remained, compared with no loss in 0.1 M-Tris/acetate buffer, pH 8, containing 0.4 M-NaCl.
Nucleonics (1966)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNucleonicsW. S. Lyon, Enzo. Ricci, and Harley H. RossCite this: Anal. Chem. 1966, 38, 5, 251–261Publication Date (Print):April 1, 1966Publication History Published online1 May 2002Published inissue 1 April 1966https://pubs.acs.org/doi/10.1021/ac60237a016https://doi.org/10.1021/ac60237a016research-articleACS PublicationsRequest reuse permissionsArticle Views64Altmetric-Citations10LEARN 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
Chemoselective Trifluoromethylation of Methyl Esters Using an Et<sub>3</sub>GeNa/C<sub>6</sub>H<sub>5</sub>SCF<sub>3</sub> Combination: Efficient Synthesis of Trifluoromethyl Ketones (1997)

Various trifluoromethyl ketones were synthesized from the corresponding methyl esters by effective nucleophilic trifluoromethylation using an Et3GeNa/C6H5SCF3 combination. This trifluoromethylation proceeded chemoselectively. When, cyclohexyl, i-propyl and t-butyl esters coexisted in the reaction system, only the methyl ester was easily transformed to the desired compounds in excellent yield. Furthermore, some protective groups were remained under this reaction condition.
Oxygen transport2. Tissue hypoxia (1998)

Tissues vary considerably in their sensitivity to hypoxia. Neurological cells tolerate hypoxia for only a few minutes whereas bladder smooth muscle may survive for several days without oxygen. This has important implications in the management of oxygen transport and monitoring of tissue hypoxia in critically ill patients.

Regional oxygen transport and cellular use are often neglected but are important in maintaining tissue function and overall survival

### Delivery to organs and tissues 

The mechanisms controlling oxygen distribution are incompletely understood but involve a series of convective and diffusive processes. Convective oxygen transport refers to the bulk movement of oxygen in air or blood and depends on active, energy consuming processes generating flow in the tracheobronchial tree and circulation. Diffusive transport refers to the passive movement of oxygen down its concentration gradient across tissue barriers, including the alveolar-capillary membrane, and across the extracellular matrix between the tissue capillaries and individual cells to mitochondria. The amount of diffusive oxygen movement depends on the oxygen tension gradient and the diffusion distance.



Effect of oxygen tension gradient and diffusion distance on availability of oxygen to cells



In many critically ill patients tissue hypoxia is due to disordered regional distribution of blood flow both between and within organs. Regional and microcirculatory distribution of cardiac output is determined by a complex interaction of endothelial, receptor, neural, metabolic, and pharmacological factors working on small resistance arterioles and precapillary sphincters. In critical illness, particularly sepsis, hypotension and loss of normal autoregulation cause shunting and tissue hypoxia in some organs despite high global oxygen delivery and mixed venous saturation. The perfusion pressure is an important determinant of regional perfusion, but adrenaline or noradrenaline given to maintain systemic blood pressure may reduce regional distribution, particularly to the renal and splanchnic capillary beds.



Severe tissue hypoxia due to capillary microthrombosis in critically ill patient with meningococcal septicaemia …
Synthesis of Carbon Spheres via a Low-Temperature Metathesis Reaction (2008)

Carbon spheres were rapidly synthesized at low temperature (300 °C) via the chemical metathesis reaction between CaC2, C2Cl4, and CCl4. X-ray diffraction and Raman results confirm the formation of hexagonal graphite with relatively low graphitization. Large quantities of carbon spheres can be observed by transmission electron microscopy in the products obtained within the reaction temperature range of 300−480 °C. The spheres with a surface area of 195.28 m2/g have a hydrogen storage capacity of 3.8 wt % at room temperature under a pressure about 10 MPa. The synergic carbon sources are likely responsible for the formation of the carbon spheres.
Comparative Raman studies of cubic and hexagonal GaN epitaxial layers (1996)

Hexagonal and cubic GaN layers are grown on (001) GaAs substrates by means of molecular beam epitaxy. First order Raman spectra are taken from these layers at various incident laser wavelengths and temperatures. The T2 transverse-optical (TO) and longitudinal-optical (LO) frequencies of cubic GaN are determined, as well as the A1 TO and LO, E1 TO, and E2 frequencies of hexagonal GaN. The T2 TO frequency of cubic GaN lies between the A1 and E1 TO frequencies of hexagonal GaN as one expects comparing the lattice dynamics of zincblende and wurtzite type crystals. The T2 TO frequency is close to the calculated value but disagrees with a recently reported experimental value. For the hexagonal layer, all frequencies are close to those previously measured. A broad Raman structure below the A1 LO peak is interpreted in terms of a disturbed long range order of the hexagonal layer.
Applications of operator separation in reflection seismology (1983)

Abstract The principle of operator separation, a generalization of operator splitting, is applied to some problems in reflection seismology. In particular, the examples of wave-equation migration of seismic data in a three-dimensional medium and accurate depth migration in a laterally varying medium are considered in light of this theory. For the case of a stratified three-dimensional medium, the standard dimensional splitting technique used in the downward-continuation step of the migration process can be replaced with full dimensional separation. The computational implications of this result are that the wave field array need only be transposed once during the downward continuation rather than 2n times, where n is the number of finite-difference steps taken in the calculation. For the example of downward continuation in a laterally varying medium, the ideas of operator separation can be used to split the downward continuation operator into two parts, one that looks like the conventional downward-continuation operator for a stratified medium, and a second that represents the correction for the effects of lateral variation.
Method for evaluating bow tie filter angle‐dependent attenuation in CT: Theory and simulation results (2009)

It is concluded that the proposed method may provide a simple noninvasive approach to characterizing the performance of bow tie filters in CT systems; however, experimental validation is necessary.
New osmium-191. -->. iridium-191m generator (1980)

A new osmium-191..-->..iridium-191m generator suitable for first-pass radionuclide angiocardiography has been developed. This generator system allows repeated elutions of 4.96-sec iridium-191m from its 15.4-day Os-191 parent. The Os-191 is loaded on an anion-exchange column (AGMP-1) and Ir-191m eluted with 0.9% NaCl at pH 1. Each elution (0.6 to 1 ml) of the generator yields about 7 to 10% Ir-191m and gives 0.003 to 0.008% of Os-191 breakthrough. Toxicity studies of the generator eluate carried out in animals support the safety of using iridium-191m in humans. The long shelf-life of the generator (approx. = 2 wk) will allow medical centers to use Ir-191m for routine clinical diagnosis. Iridium-191m obtained by this method should find additional useful applications in nuclear medicine.
Rapid and Efficient Isolation of Genes for Biosynthesis of Peptide Antibiotics from Gram-positive Bacterial Strains (1998)

Peptide synthetases are large multifunctional enzyme complexes that catalyze the nonribosomal synthesis of a structurally diverse family of peptide antibiotics. These enzymes are composed of functionally independent domains with independent enzymatic activities. Their specific linkage order of domains forms the protein template that defines the sequence of the incorporated amino acids. Within each domain, several motifs of highly conserved sequences have been identified from the sequence alignment of the various peptide synthetases [30]. Taking advantage of the conserved nucleotide sequence of Core 1 and Core 2, we designed PCR primers to amplify the peptide synthetase genes from three different gram-positive bacterial strains. Nucleotide sequence analysis of the amplified PCR products from those three strains showed significant homology to various peptide synthetase genes, suggesting that the PCR products are parts of peptide synthetase genes. Therefore, this rapid and efficient PCR technique can be used for the isolation of peptide synthetase genes from various strains.
Permanent Labels for Identifying Plant Materials (1987)

Abstract Labeling to identify plant material is an important procedure in plant science research, teaching, and extension. Labels for perennial plants should be durable and easy to read. Further, a labeling system should be economical and flexible in the size of the labels that may be used. We have developed a flexible labeling system that satisfies these requirements and offers other advantages as well. This labeling system was adapted from the ear tag labeling methods used in animal science (1). It uses Ritchey marking paint (RMP), a wire tie, and a plastic tag.
Proteinase activated receptor 2: role of extracellular loop 2 for ligand‐mediated activation (1999)

1. Rat proteinase-activated receptor-2 (PAR2) variants were stably expressed in rat KNRK cells: (a) wild-type (wt) - PAR2; (b) PAR2PRR, with the extracellular loop 2 (EL-2) sequence P231E232E233mutated to PRR and (c) PAR2NET, with the EL-2 sequence, PEEV changed to NETL. Cell lines were evaluated for their sensitivity (calcium signalling) towards trypsin and the receptor-activating peptides, SLIGRL-NH2, SLIGEL-NH2, trans-cinnamoyl(tc)-LIGRLO-NH2, and SFLLR-NH2. 2. SLIGEL-NH2 exhibited low potency (1 : 200 relative to SLIGRL-NH2) in wild-type PAR2. Its activity was increased 5 fold in PAR2PRR, but it was inactive in PAR2NET. 3. In PAR2PRR, the potencies of SLIGRL-NH2, tc-LIGRLO-NH2, and SFLLR-NH2 were decreased by 80 - 100 fold. But, the potency of trypsin was decreased by only 7 fold. 4. In PAR2NET, highly homologous in EL-2 with proteinase-activated receptor-1 (PAR1), the potency of the PAR1-derived peptide, SFLLR-NH2, was reduced by 100 fold compared with wt-PAR2, whereas the potency of the PAR2-derived AP, SLIGRL-NH2 was reduced 10 fold. In contrast, the potency of trypsin in PAR2NET was almost the same as in wt-PAR2. 5. We conclude that the acidic EL-2 tripeptide, PEE, in PAR2 plays an important role in governing agonist activity. 6. The data obtained with the PEEV-->NETL mutation suggested: (a) that SLIGRL-NH2 and SFLLR-NH2 interact in a distinct manner with PAR2 and (b) that SFLLR-NH2 may interact differently with PAR2 than it does with PAR1. 7 The differential reductions in the potencies of SLIGRL-NH2, compared with trypsin in the PAR2PRR and PAR2NET cell lines point to differences between the interactions of the trypsin-revealed tethered ligand and the free receptor-activating peptide with PAR2.
Staging atherosclerosis using ultrasound, strain and photoacoustic imaging (2010)

The rupture of atherosclerotic plaques represents one of the leading causes of morbidity and mortality. The aim of our study is to assess the morphology, functionality and composition of plaques formed in common carotid artery using a non-invasive in-vivo imaging technology, namely combined ultrasound, strain and photoacoustics. The imaging approach was tested ex-vivo on excised rabbit aortas (two with and two without plaques) using the integrated vascular imaging probe. The artery was flushed with blood at a pulsatile flow (1.5 Hz pulse rate and 50 m/s flow velocity). Ultrasound B-mode images and strain images, recorded at 296 frames per second, were obtained using a 12 MHz linear array transducer. For photoacoustic imaging the same ultrasound transducer was coupled with 19 optical fibers connected to OPO laser system (operated at 5 ns pulse duration, 590 nm and 700 nm spectral range). To analyze the advantages of the three imaging techniques, hyper- and hypoechogenic regions were separately isolated and the corresponding strain and photoacoustic signals were compared. Spatial variations in ultrasound echogeneicity are related to changes in arterial structure and function, i.e. hyperechogenic regions correspond to 15% or more decrease in peak strain rate and correlate with fibrotic tissue (as identified by photoacoustic images). The results of our study suggest that combined ultrasound, strain and photoacoustic imaging provides complementary information. Analysis of co-registered ultrasound, strain and photoacoustic images can be used to differentiate morphology, functionality and composition of plaques necessary for clinical diagnosis.
Mosaic Organization of Orthologous Sequences in Grass Genomes (2002)

Although comparative genetic mapping studies show extensive genome conservation among grasses, recent data provide many exceptions to gene collinearity at the DNA sequence level. Rice, sorghum, and maize are closely related grass species, once sharing a common ancestor. Because they diverged at different times during evolution, they provide an excellent model to investigate sequence divergence. We isolated, sequenced, and compared orthologous regions from two rice subspecies, sorghum, and maize to investigate the nature of their sequence differences. This study represents the most extensive sequence comparison among grasses, including the largest contiguous genomic sequences from sorghum (425 kb) and maize (435 kb) to date. Our results reveal a mosaic organization of the orthologous regions, with conserved sequences interspersed with nonconserved sequences. Gene amplification, gene movement, and retrotransposition account for the majority of the nonconserved sequences. Our analysis also shows that gene amplification is frequently linked with gene movement. Analyzing an additional 2.9 Mb of genomic sequence from rice not only corroborates our observations, but also suggests that a significant portion of grass genomes may consist of paralogous sequences derived from gene amplification. We propose that sequence divergence started from hotspots along chromosomes and expanded by accumulating small-scale genomic changes during evolution.
The effects of angiotensin on the diagnostics and haemodynamics in renal angiography. (1983)

In 20 patients referred for renal angiography, series were obtained, 30 s., 3 and 10 min. (control) after administration of 0.5 microgram of angiotensin into the selective arterial catheter. 30 s. after angiotensin there was decreased renal volume, decreased renal blood flow, unchanged arterial diameters but narrower veins. The vascular resistance was increased. The diagnostics in neoplasms and cysts were not improved. Angiotensin administration cannot replace a well performed standard renal angiography.
Antisickling effect of tellurite: a potent membrane-acting agent in vitro (1984)

Potassium tellurite (K2TeO3) was found to be a potent antisickling agent that inhibited red cell sickling at concentrations less than 10 mumol/L. The inhibitory effect depended on the incubation time, with the effect increasing with longer incubation periods. Because tellurite causes swelling of red cells, and because the antisickling effect of tellurite correlated with the degree of red cell swelling, the antisickling effect of tellurite is assumed to be due to the decreased mean cell hemoglobin concentration. Swelling of red cells by tellurite was accelerated by the addition of reduced glutathione. Tellurite appears to be a new type of antisickling agent that interacts with the red cell membrane.
Software development with grammatical approach (2004)

The paper presents a grammatical approach to problem solving. It supports formal software specification using attribute grammars, from which a rapid prototype can be generated, as well as the incremental software development. Domain concepts and relationships among them have to be identified from a problem statement and represented as a context-free grammar. The obtained context-free grammar describes the syntax of a domain-specific language whose semantics is the same as the functionality of the system under implementation. The semantics of this language is then described using attribute grammars from which a compiler is automatically generated. The execution of a particular program written in that domain-specific language corresponds to the execution of a prototype of the system on a particular use-case.