gebhart/patrepeval huggingface dataset:
Prenylated 4-Hydroxybenzoic Acid Derivatives from Piper marginatum (1988)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPrenylated 4-Hydroxybenzoic Acid Derivatives from Piper marginatumAnderson Maxwell and Dave RampersadCite this: J. Nat. Prod. 1988, 51, 2, 370–373Publication Date (Print):March 1, 1988Publication History Published online1 July 2004Published inissue 1 March 1988https://pubs.acs.org/doi/10.1021/np50056a037https://doi.org/10.1021/np50056a037research-articleACS PublicationsRequest reuse permissionsArticle Views263Altmetric-Citations15LEARN 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
Protecting RAID Arrays against Unexpectedly High Disk Failure Rates (2014)

Disk failure rates vary so widely among different makes and models that designing storage solutions for the worst case scenario is a losing proposition. The approach we propose here is to design our storage solutions for the most probable case while incorporating in our design the option of adding extra redundancy when we find out that its disks are less reliable than expected. To illustrate our proposal, we show how to increase the reliability of existing two-dimensional disk arrays with n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> data elements and 2n parity elements by adding n additional parity elements that will mirror the contents of half the existing parity elements. Our approach offers the three advantages of being easy to deploy, not affecting the complexity of parity calculations, and providing a five-year reliability of 99.999 percent in the face of catastrophic levels of data loss where the array would lose up to a quarter of its storage capacity in a year.
A new smart device array structure for statistical investigations of BTI degradation and recovery (2011)

The paper presents the development of new universal smart test-structure solving the typical restrictions of BTI device array investigations. Our integrated structure combined with an adapted measurement methodology ensures very short and most notably uniform recovery times for each device of the entire array. This is the absolutely required precondition for statistical evaluations of the BTI degradation and recovery behavior. Our new smart device array structure approach enables us to investigate the statistic of the parameter degradations itself and the combination of the variability of virgin devices at zero hour together with the additional variations due the non-uniform behavior of BTI degradation.
Efficient synthesis of 14-hydroxymorphinans from codeine (1981)

Codeine is converted to 7,8-dihydro-14-hydroxynorcodeinone (noroxycodone) in six steps and 52% overall yield of the noroxymorphone in seven steps and 43% overall yield. N-Demethylation and oxidation of codeine afford N-(ethoxycarbonyl)norcodeinone, which is converted to its dienol acetate derivative and oxidized with singlet oxygen to give N-(ethoxycarbonyl)-14-hydroxynorcodeinone in the key step. Hydrogenation of the latter affords N-(ethoxycarbonyl)noroxycodone, which upon acid hydrolysis yields noroxycodone. Alternatively, O-demethylation of N-(ethoxycarbonyl)noroxycodone with boron tribromide and subsequent acid hydrolysis gives noroxymorphone. The results of the singlet oxygen oxidation of the pyrrolidine dienamine derived from N-(ethoxycarbonyl)norcodeinone are also described.
4-D modeling of sound propagation in shallow water with anisotropic sediment layers (1998)

A highly efficient 4-D PE model is developed to study broadband sound propagation at the Atlantic Generating Station (AGS) site. Extensive core data has shown that the sediment at this AGS site consists of multiple layers which vary in both range and azimuth. Consequently, sound propagation in the water column in this area is significantly affected by the complex sediment structure due to the fact that the layered sediment acts like a bandpass filter in which broadband acoustic energy is selectively broken into narrow-band components propagating in different layers, usually referred as sediment mode trapping. The details of the range, azimuth, frequency, and bandwidth dependences as well as their relationships to the sediment structure of such mode trapping effect is numerically explored by performing the 4-D PE model. The empirical orthogonal function representation method is employed to transfer the geoacoustic parameters of the sediment core data into PE inputs. The broadband travel time results at eight different bearings are compared with the existing experimental data. The importance of the 3-D effects is also examined by comparing the numerical results of azimuthal coupled and uncoupled models.
Electrodynamics of Electronic Paper Based on Total Internal Reflection (2018)

Electronic ink displays based on total internal reflection are promising for video-speed paperlike devices, but the electrophoretic switching behavior and voltage-reflection relation for high particle concentrations remain unclear. This study highlights the importance of countercharges and surface charges. The dynamic switching of electronic ink according to electric field and particle concentration is discussed, and an analytic description of steady-state grey levels is given. The insight from the electrooptical model is relevant to developing next-generation video-speed displays, liquid-toner printers, and other applications of electronic ink.
Avian Lymphomatosis. VI. A Virus of Unusual Potency and Pathogenicity (1964)

It is well established that avian lymphomatosis is of viral etiology. The shortcomings of viral isolates used experimentally have been that they require long incubation periods and special genetic lines of chickens, and are of low or inconsistent pathogenicity. Burmester et al. (1) demonstrated the presence of a filterable agent, designated as RPL-12 virus, in an avian lymphoid tumor. The response of line 15 chickens to graded doses of this virus demonstrated an infective range from a low of 55.5% in a low-dose lot to a high of 90.1% in a highdose lot and the average age at death in the same lots was respectively 128.2 and 55.6 days (2). The manifestations of cellular and cell-free preparations of JM lymphomatosis virus in Cornell's S-line chickens have been reported by Sevoian et al. (5,6,7,8). The response was measured by mortality, and the presence of gross lesions in the survivors during a 3-week experimental period. The mortality rarely exceeded 10% during this period, and, more often, none occurred. Therefore, virus titers of cellular preparations were expressed as the 50% infective dose and ranged
Attenuation of the Editing Activity of the<i>Escherichia coli</i>Leucyl-tRNA Synthetase Allows Incorporation of Novel Amino Acids into Proteins in Vivo (2002)

The fidelity of translation is dependent on the specificity of the aminoacyl-tRNA synthetases (aaRSs). The aaRSs that activate the hydrophobic amino acids leucine, isoleucine, and valine employ a proofreading mechanism that hydrolyzes noncognate aminoacyl adenylates and misaminoacylated tRNAs. Discrimination between structurally similar amino acids by these AARSs is believed to operate by a double-sieve principle, wherein a separate editing domain governs hydrolysis on the basis of the size and hydrophilicity of the amino acid side chain. Leucyl-tRNA synthetase (LeuRS) relies on its editing function to correct misaminoacylation of tRNA(Leu) by isoleucine and methionine. Thr252 of Escherichia coli LeuRS has been shown previously to be important in defining the size of the editing cavity. Here we report the isolation and characterization of three LeuRS mutants with point mutations at this position (T252Y, T252L, and T252F). The proofreading activity of the synthetase is significantly impaired when an amino acid bulkier than threonine is introduced. The rate of misaminoacylation of tRNA(Leu) by isoleucine and valine increases with the increasing size of the amino acid substituent at position 252, and the noncognate amino acids norvaline and norleucine are inserted efficiently at the leucine sites of recombinant proteins under conditions of constitutive overexpression of the T252Y mutant in E. coli. In addition, the unsaturated amino acids allylglycine, homoallylglycine, homopropargylglycine, and 2-butynylalanine all support protein synthesis in E. coli hosts harboring the mutant synthetase. These results demonstrate that programmed manipulation of the editing cavity can allow in vivo incorporation of novel protein building blocks.
Sildenafil and cardiomyocyte-specific cGMP signaling prevent cardiomyopathic changes associated with dystrophin deficiency (2008)

We recently demonstrated early metabolic alterations in the dystrophin-deficient mdx heart that precede overt cardiomyopathy and may represent an early "subclinical" signature of a defective nitric oxide (NO)/cGMP pathway. In this study, we used genetic and pharmacological approaches to test the hypothesis that enhancing cGMP, downstream of NO formation, improves the contractile function, energy metabolism, and sarcolemmal integrity of the mdx heart. We first generated mdx mice overexpressing, in a cardiomyocyte-specific manner, guanylyl cyclase (GC) (mdx/GC(+/0)). When perfused ex vivo in the working mode, 12- and 20-week-old hearts maintained their contractile performance, as opposed to the severe deterioration observed in age-matched mdx hearts, which also displayed two to three times more lactate dehydrogenase release than mdx/GC(+/0). At the metabolic level, mdx/GC(+/0) displayed a pattern of substrate selection for energy production that was similar to that of their mdx counterparts, but levels of citric acid cycle intermediates were significantly higher (36 +/- 8%), suggesting improved mitochondrial function. Finally, the ability of dystrophin-deficient hearts to resist sarcolemmal damage induced in vivo by increasing the cardiac workload acutely with isoproterenol was enhanced by the presence of the transgene and even more so by inhibiting cGMP breakdown using the phosphodiesterase inhibitor sildenafil (44.4 +/- 1.0% reduction in cardiomyocyte damage). Overall, these findings demonstrate that enhancing cGMP signaling, specifically downstream and independent of NO formation, in the dystrophin-deficient heart improves contractile performance, myocardial metabolic status, and sarcolemmal integrity and thus constitutes a potential clinical avenue for the treatment of the dystrophin-related cardiomyopathies.
RAPID INDUCTION OF MAMMARY CARCINOMA IN THE RAT AND THE INFLUENCE OF HORMONES ON THE TUMORS (1959)

A study was made of the optimal conditions for the induction of mammary cancer in the rat. 3-Methylcholanthrene was administered via the gastrointestinal tract, and a simple technique was worked out for inducing mammary cancer regularly and rapidly. Under conducive conditions, which were readily reproduced, multiple mammary carcinomas and these tumors only were induced in every rat in repeated experiments in 60 days or less. In the strain of animal employed in the present experiments, the rapid induction of mammary cancer proved to be a function of (a) dosage, (b) the timing of administration of the aromatic hydrocarbon, and (c) a favoring hormonal status of the recipient. Most of the established tumors were hormone-dependent because they diminished markedly in size after hormone withdrawal through ovariectomy or hypophysectomy. Similar regression of the tumors was frequently achieved by the administration of dihydrotestosterone. Shrinkage of the cancers was accompanied by atrophic changes. Experimental mammary tumors with these physiologic characteristics have not been recognized hitherto. The minority of mammary cancers continued to grow after ovariectomy; these are hormone-independent tumors and tumors of this sort had a characteristic cytologic appearance following modification of the endocrine state. The cell population of a single tumor was not always uniform in its response to appropriate hormonal modifications. In certain tumors in response to changes in the endocrine status of the host many of the cells underwent atrophy whilst other adjacent cells in the same tumor continued to grow so that the net result was a hormone-independent tumor. Hypophysectomy was the most effective method found to induce regression of mammary cancer in the present experiments.
DNA sequences at the ends of the genome of bacteriophage Mu essential for transposition. (1985)

We have determined the minimal DNA sequences at the ends of the genome of bacteriophage Mu that are required for its transposition. A mini-Mu was constructed on a multicopy plasmid that enabled the manipulation of the DNA sequences at its ends without affecting the genes essential for transposition. The genes A and B, which were cloned outside the ends of the mini-Mu on the same plasmid, were both needed for optimal transposition. In our experimental system the predominant end products of the transposition are cointegrates both in the presence and in the absence of B. Two regions ending approximately 25 and 160 bp from the left end and one ending approximately 50 bp from the right end appear to be essential for optimal transposition. Overlapping with these regions, a 22-base-pair sequence was recognized with the consensus Y-G-T-T-C-A-Y-T-N-N-A-A-R-Y-R-C-G-A-A-A-A, where Y and R represent any pyrimidine and purine, respectively. At the left end these sequences occur as direct repeats; at the right end this sequence is inverted with respect to those at the left end.
Variational optimization for call center staffing (2005)

Article Variational optimization for call center staffing Share on Authors: Robert C. Hampshire Princeton University, Princeton, New Jersey Princeton University, Princeton, New JerseyView Profile , William A. Massey Princeton University, Princeton, New Jersey Princeton University, Princeton, New JerseyView Profile Authors Info & Claims TAPIA '05: Proceedings of the 2005 conference on Diversity in computingOctober 2005 Pages 4–6https://doi.org/10.1145/1095242.1095245Published:19 October 2005 2citation192DownloadsMetricsTotal Citations2Total Downloads192Last 12 Months7Last 6 weeks1 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access
Solar imaging with a segmented adaptive mirror (1992)

A 19-segment adaptive-mirror system is currently being used on the Sacramento Peak 76-cm Tower Telescope to remove wave-front distortions resulting from atmospheric turbulence. The system has proven to be capable of substantially improving the quality of an image, at times achieving 0.33-arcsec resolution in visible wavelengths under 1-3-arcsec seeing conditions. An improvement in resolution seems to occur across a large field of view that is, at times, 30 arcsec in diameter.
Thermoacoustic refrigerator for space applications (1993)

A new spacecraft cryocooler which uses resonant high-amplitude sound waves in inert gases to pump heat is described. The phasing of the thermoacoustic cycle is provided by thermal conduction. This natural phasing allows the entire refrigerator to operate with only one moving part (the loudspeaker diaphragm). A spacequalified thermoacoustic refrigerator was flown on the Space Shuttle Discovery (STS-42) in January, 1992. It was entirely autonomous, had no sliding seals, required no lubrication, used mostly low-tolerance machined parts, and contained no expensive components. Thermoacoustics is shown to be a competitive candidate for food refrigerator/freezers and commercial/residential air conditioners. The design and performance of the Space ThermoAcoustic Refrigerator (STAR) is described.
Doping by Secondary Implantation (1986)

The dopants usually employed in Si molecular beam epitaxy have been found to exhibit adlayer formation as well as a low coefficient of spontaneous incorporation. The dopant incorporation based on the interaction of Si+ ions with dopant adatoms is proposed as a doping method denoted as doping by secondary implantation. Experimental results on secondary implantation of Sb into (100) Si MBE layers are presented. Si ions are employed that either originate from the electron‐gun‐heated silicon source itself or optionally from a cross beam ionization ring on top of the silicon source. Doping uniformity within a 3 in. wafer is found to be in the 5% range. Dopant activation coefficients of almost unity at least up to a doping level of 1019 cm−3 are found, without mobility degradation and without evidence of a simultaneous dopant adlayer sputtering at a growth temperature of 650°C and ion energies up to 1000 eV. Results from secondary implantation experiments are expected to be a suitable tool for the analysis of adlayer properties such as e.g., cluster formation.
Effects of Forced Expression of an NH2-terminal Truncated β-Catenin on Mouse Intestinal Epithelial Homeostasis (1998)

beta-Catenin functions as a downstream component of the Wnt/Wingless signal transduction pathway and as an effector of cell-cell adhesion through its association with cadherins. To explore the in vivo effects of beta-catenin on proliferation, cell fate specification, adhesion, and migration in a mammalian epithelium, a human NH2-terminal truncation mutant (DeltaN89 beta-catenin) was expressed in the 129/Sv embryonic stem cell-derived component of the small intestine of adult C57Bl/6-ROSA26 left and right arrow 129/Sv chimeric mice. DeltaN89 beta-Catenin was chosen because mutants of this type are more stable than the wild-type protein, and phenocopy activation of the Wnt/Wingless signaling pathway in Xenopus and Drosophila. DeltaN89 beta-Catenin had several effects. Cell division was stimulated fourfold in undifferentiated cells located in the proliferative compartment of the intestine (crypts of Lieberkühn). The proliferative response was not associated with any discernible changes in cell fate specification but was accompanied by a three- to fourfold increase in crypt apoptosis. There was a marked augmentation of E-cadherin at the adherens junctions and basolateral surfaces of 129/Sv (DeltaN89 beta-catenin) intestinal epithelial cells and an accompanying slowing of cellular migration along crypt-villus units. 1-2% of 129/Sv (DeltaN89 beta-catenin) villi exhibited an abnormal branched architecture. Forced expression of DeltaN89 beta-catenin expression did not perturb the level or intracellular distribution of the tumor suppressor adenomatous polyposis coli (APC). The ability of DeltaN89 beta-catenin to interact with normal cellular pools of APC and/or augmented pools of E-cadherin may have helped prevent the 129/Sv gut epithelium from undergoing neoplastic transformation during the 10-mo period that animals were studied. Together, these in vivo studies emphasize the importance of beta-catenin in regulating normal adhesive and signaling functions within this epithelium.
The sterilization of surgical rubber gloves and plastic tubing by means of ionizing radiation (1960)

Threads were infected with the spores of four species of bacteria and put inside rubber gloves which were sealed into plastic bags and irradiated with electrons or gamma rays. A dose of 1·5 Mrad. killed approximately 99·99% of the spores of each species and a dose of 2·5 Mrad. appeared to give an adequate margin of safety for sterilization. Spores were similarly killed inside plastic tubing and within the lumen of hypodermic needles. The tensile strength of the gloves decreased with increasing doses of radiation so that the rough, solution-dipped gloves tested were significantly weaker after 8·0 Mrad., but the smooth gloves tested still complied with the British Standard after 30 Mrad. When vacuum-packed before irradiation, rough gloves were still satisfactory after 16 Mrad., and smooth gloves were apparently unaffected by 30 Mrad.; they could, therefore, be sterilized six and twelve times, respectively. Radiation gives dependable sterilization of rubber gloves, and the use of a sealed plastic package obviates subsequent contamination. The possibility of using disposable radiation-sterilized gloves is discussed, the use of a plastic radiation indicator suggested and the practical applications of radiation sterilization in the hospital considered.
Cell surface characteristics of Lactobacillus casei subsp. casei, Lactobacillus paracasei subsp. paracasei, and Lactobacillus rhamnosus strains (1997)

Hydrophilic and electrostatic cell surface properties of eight Lactobacillus strains were characterized by using the microbial adhesion to solvents method and microelectrophoresis, respectively. All strains appeared relatively hydrophilic. The strong microbial adhesion to chloroform, an acidic solvent, in comparison with microbial adhesion to hexadecane, an apolar n-alkane, demonstrated the particularity of lactobacilli to have an important electron donor and basic character and consequently their potential ability to generate Lewis acid-base interactions with a support. Regardless of their electrophoretic mobility (EM), strains were in general slightly negatively charged at alkaline pH. A pH-dependent behavior concerning cell surface charges was observed. The EM decreased progressively with more acidic pHs for the L. casei subsp. casei and L. paracasei subsp. paracasei strains until the isoelectric point (IEP), i.e., the pH value for which the EM is zero. On the other hand, the EM for the L. rhamnosus strains was stable from pH 8 to pH 3 to 4, at which point there was a shift near the IEP. Both L. casei subsp. casei and L. paracasei subsp. paracasei strains were characterized by an IEP of around 4, whereas L. rhamnosus strains possessed a markedly lower IEP of 2. The present study showed that the cell surface physicochemical properties of lactobacilli seem to be, at least in part and under certain experimental conditions, particular to the bacterial species. Such differences detected between species are likely to be accompanied by some particular changes in cell wall chemical composition.
Some recent developments in solid state galvanic sensors (1982)

A critical revi<:w of the possibilities of measuring the ~artlal pressure of sulfur using solid state galvanic cells )'n;;cd on AgI, C" , B-alumina, CaO-Zr02' Na2S04-I and doped ;:":;, ,,,Ilil "Iltl ,,11: auxiliary "jectrodes are presentlOu. SOIll..., df tllc!iL' sYHtcmH h,}vu inherent limltntlol1$ when <:xl'o" ...d to environments contilining both oxygen and sulfur. Electrode polarization due to electronic conduction in the solid electrolyte is a significant factor limiting the ;lC'e,"'acy of isotlwrm:l1 cell",. The electrochemical flux of{lit' !'\\)ndlwl Ill}: Ion LhnHO',h tht' ('!('ctrojyt(~ C:Ul },(,! llIinlnliz(,{j pfUjJL!f cell. dL:~) i.t',11. Noni!:iot.herm~ll cells \\.Jlth temperaLure compensated reference electrodes have a number of advantages over thC'ir isothermal counterparts.