gebhart/patrepeval huggingface dataset:
Series resonant ZCS–PFM DC–DCconverter with multistage rectified voltage multiplierand dual-mode PFM control scheme for medical-use high-voltage X-ray power generator (2000)

In general, high-voltage DC power supplies employing a variety of high-frequency inverters are implemented for constant value control schemes. In particular, their good transient and steady state performances cannot be achieved under wide load variations for a medical-use high-voltage X-ray generator, ranging from 20 kV to 150 kV in the output voltage and from 0.5 mA to 1250 mA, respectively. A high-voltage DC power supply designed for X-ray power generator applications is considered, which uses a series resonant inverter-linked multistage DC voltage multiplier instead of a conventional high-voltage diode module rectifier connected to the secondary side of a high-voltage transformer. A constant on-time/variable frequency control scheme of this converter operating at zero-current soft switching mode is described. Introducing the capacitor–diode cascaded multistage voltage multiplier, the secondary turn numbers and secondary-side stray capacitance of the high-voltage, high-frequency transformer, as well as the rectifier diode voltage ratings, can be greatly reduced. It is shown that the proposed converter control scheme of the two-step selective changed frequency selection switching is more effective for improving the output voltage responses. The series resonant high-frequency transformer-linked voltage-multiplying rectifier is evaluated for an X-ray high-voltage generator on the basis of simulation analysis and observed data in experiment.
Specificity of creatine kinase. New glycocyamines and glycocyamine analogs related to creatine (1971)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpecificity of creatine kinase. New glycocyamines and glycocyamine analogs related to creatineGerald L. Rowley, Arno L. Greenleaf, and George L. KenyonCite this: J. Am. Chem. Soc. 1971, 93, 21, 5542–5551Publication Date (Print):October 1, 1971Publication History Published online1 May 2002Published inissue 1 October 1971https://pubs.acs.org/doi/10.1021/ja00750a038https://doi.org/10.1021/ja00750a038research-articleACS PublicationsRequest reuse permissionsArticle Views1299Altmetric-Citations109LEARN 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
Synthesis and in Vitro Characterization of a Dendrimer−MORF Conjugate for Amplification Pretargeting (2008)

Amplification pretargeting can play an important role in molecular imaging by significantly increasing the accumulation of signal in target tissues. Multiple-step amplification pretargeting offers the potential to greatly improve target localization of effector molecules through the intermediate use of polymers conjugated with multiple copies of complementary oligomers. In this study, PAMAM dendrimer generation 3 (G3) was conjugated with multiple copies of a phosphorodiamidate morpholino (MORF) oligomer. Characterization of the conjugate by native-PAGE and SE-HPLC demonstrated that the conjugation was successful. The average numbers of MORF groups in the G3-MORF conjugate, both attached and accessible to the (99m)Tc labeled complementary MORF (cMORF), were determined. The antitumor antibody CC49 was conjugated with both MORF and cMORF (collectively (c)MORF) at an average of about one group per molecule. Nine of the 32 carboxyl groups of the dendrimer were modified with MORF, of which 90% were accessible in solution to (99m)Tc-cMORF. After purification, the G3-MORF was radiolabeled with tracer (99m)Tc-labeled cMORF (i.e., G3-MORF/(99m)Tc-cMORF) and added to the antibody CC49 previously conjugated with cMORF (i.e., CC49-cMORF/G3-MORF/(99m)Tc-cMORF), the complex demonstrated a single peak on SE-HPLC as evidence of complete hybridization between G3-MORF/(99m)Tc-cMORF and CC49-cMORF. The CC49-(c)MORF were bound to both Protein G and Protein L coated plates, and G3-MORF was added to hybridize with CC49-cMORF before the (99m)Tc-cMORF was added to test amplification pretargeting. In comparison to conventional pretargeting without the G3-MORF, the signal was amplified about 6 and 14 times, respectively, showing that the G3-MORF participated in amplifying the signal. Further amplification studies using the CC49-(c)MORF for LS174T tumor cells in tissue culture also demonstrated clear evidence of signal amplification.
Anderson Localization and Nonlinearity in One-Dimensional Disordered Photonic Lattices (2008)

We experimentally investigate the evolution of linear and nonlinear waves in a realization of the Anderson model using disordered one-dimensional waveguide lattices. Two types of localized eigenmodes, flat-phased and staggered, are directly measured. Nonlinear perturbations enhance localization in one type and induce delocalization in the other. In a complementary approach, we study the evolution on short time scales of delta-like wave packets in the presence of disorder. A transition from ballistic wave packet expansion to exponential (Anderson) localization is observed. We also find an intermediate regime in which the ballistic and localized components coexist while diffusive dynamics is absent. Evidence is found for a faster transition into localization under nonlinear conditions.
Palladium-catalysed heteroannulation of acetylenic compounds: a facile method for the synthesis of benzofurans (1992)

A convenient and general method for the synthesis of benzofurans from o-iodophenol and acetylenic compounds under palladium-catalysed conditions is described.
Tunable LiF:F/sub 2//sup -/ color center laser with an intracavity integrated-optic output coupler (1996)

A new LiF:F/sub 2//sup -/ color center laser operation has been achieved by inserting a SiO/sub 2/ thin-film waveguide in the laser cavity. The waveguide was deposited on LiF bulk crystal substrate with a holographic grating. The laser beam from the waveguide was tunable in 1150-1172 nm spectral range. The maximum ratio of the pulse energy of the laser radiation coupled out through the waveguide to that of the pump-radiation was 0.3%. The beam was stretched into the direction perpendicular to the waveguide plane, with a divergency of 7.2/spl times/10/sup -2/.
Bifunctional CYP81AA proteins catalyse identical hydroxylations but alternative regioselective phenol couplings in plant xanthone biosynthesis (2016)

Xanthones are natural products present in plants and microorganisms. In plants, their biosynthesis starts with regioselective cyclization of 2,3',4,6-tetrahydroxybenzophenone to either 1,3,5- or 1,3,7-trihydroxyxanthones, catalysed by cytochrome P450 (CYP) enzymes. Here we isolate and express CYP81AA-coding sequences from Hypericum calycinum and H. perforatum in yeast. Microsomes catalyse two consecutive reactions, that is, 3'-hydroxylation of 2,4,6-trihydroxybenzophenone and C-O phenol coupling of the resulting 2,3',4,6-tetrahydroxybenzophenone. Relative to the inserted 3'-hydroxyl, the orthologues Hc/HpCYP81AA1 cyclize via the para position to form 1,3,7-trihydroxyxanthone, whereas the paralogue HpCYP81AA2 directs cyclization to the ortho position, yielding the isomeric 1,3,5-trihydroxyxanthone. Homology modelling and reciprocal mutagenesis reveal the impact of S375, L378 and A483 on controlling the regioselectivity of HpCYP81AA2, which is converted into HpCYP81AA1 by sextuple mutation. However, the reciprocal mutations in HpCYP81AA1 barely affect its regiospecificity. Product docking rationalizes the alternative C-O phenol coupling reactions. Our results help understand the machinery of bifunctional CYPs.
High-Level Transduction and Gene Expression in Hematopoietic Repopulating Cells Using a Human Imunodeficiency Virus Type 1-Based Lentiviral Vector Containing an Internal Spleen Focus Forming Virus Promoter (2002)

Prolonged exposure of human hematopoietic stem cells (HSC) to growth factors for efficient transduction by murine oncoretroviral vectors has major detrimental effects on repopulating activity. In this study, we have used a vesicular stomatitis virus G envelope protein (VSV-G)-pseudotyped human immunodeficiency virus type 1 (HIV-1) lentiviral-based vector system to transduce cord blood (CB) CD34+ cells over a limited time period (< or =24 hours). Under these conditions, significant gene marking was observed in engrafted human lymphoid, myeloid, and progenitor cells in all transplanted Severe Combined Immunodeficient (SCID) mice. To enhance the level of gene expression in hematopoietic cells, we also generated a series of lentiviral vectors incorporating the spleen focus forming virus (SFFV) long terminal repeat (LTR) sequences, and the Woodchuck hepatitis virus posttranscriptional regulatory element (WPRE). By including the central polypurine tract (cPPT) sequence of HIV-1 we were then able to achieve high levels of transduction (over 80%) and gene expression in vivo after a single exposure to viral supernatant. These results demonstrate that lentiviral vectors are highly effective for gene transfer to human HSC, and that SFFV regulatory sequences can be successfully incorporated to enhance the long-term expression of a transgene in primary human hematopoietic cells in vivo.
A microcomputer program for stimulating effects of physical transport processes on fish larvae (1992)

ABSTRACT A simple microcomputer program uses Lagrangian particle tracking to simulate the fates of individual larvae subject to wind‐ and tide‐driven advection fields and diffusion. Space/time advection patterns are provided to the program as inputs; thus, the program can use results from various hydrodynamic models. The program can simultaneously track several groups of larvae that are assigned varying attributes, including (1) body size, to allow simulation of effects of variation in growth rates; (2) spawning locations and times; (3) vertical migration behavior; and (4) settlement strategy (duration of larval period, depth conditions for settlement). The model is intended as an exploratory tool to help identify alternative hypotheses that might explain observed life history patterns and causes of inter‐annual variation in recruitment rate. For English sole in the Hecate Strait, B.C., the model leads us to hypothesize that observed spawning locations have resulted from a tradeoff between places that would provide the best feeding opportunities and places that would minimize risk of advective export to unfavorable rearing habitats.
Development of C5a receptor antagonists. (1999)

During host defense, the human complement system of plasma proteins initiates inflammatory and cellular immune responses to stimuli such as infectious organisms, chemical and physical injury, radiation and neoplasia. Elevated levels of one of these plasma proteins C5a, a 74 amino acid peptidic anaphylatoxin which is one of the most potent pro-inflammatory agents, correlate with the initiation and development of many inflammatory diseases. New agents which prevent binding of C5a to its G-protein-coupled receptors can inhibit the pro-inflammatory actions of C5a and thus be potentially used to treat chronic inflammatory disorders driven by complement activation and C5a production. In recent years significant progress has been made towards the development of potent antagonists of human C5a receptors and clinically useful compounds can reasonably be expected within the next few years.
The predominance of metabolic regulation of cerebral blood flow and the lack of "Classic" autoregulation curves in the viable brain (2012)

In the functioning and viable brain, metabolic regulation of cerebral blood flow (CBF) predominates, leading to the lack of an obvious relationship between perfusion pressure and flow. This predominance of metabolic regulation is robust and preserved over a wide range of brain injury, with pressure autoregulation necessary but not clinically apparent in the metabolically active brain. This robust and constantly varying relationship of pressure and flow shown by our real-time measurements of fCBF has important implications for interpreting clinical measurements of autoregulation. Perhaps most importantly, the development of a correlation between pressure and flow may indicate and be an early warning of deterioration.
The HDAC inhibitor 4b ameliorates the disease phenotype and transcriptional abnormalities in Huntington's disease transgenic mice (2008)

Transcriptional dysregulation has emerged as a core pathologic feature of Huntington's disease (HD), one of several triplet-repeat disorders characterized by movement deficits and cognitive dysfunction. Although the mechanisms contributing to the gene expression deficits remain unknown, therapeutic strategies have aimed to improve transcriptional output via modulation of chromatin structure. Recent studies have demonstrated therapeutic effects of commercially available histone deacetylase (HDAC) inhibitors in several HD models; however, the therapeutic value of these compounds is limited by their toxic effects. Here, beneficial effects of a novel pimelic diphenylamide HDAC inhibitor, HDACi 4b, in an HD mouse model are reported. Chronic oral administration of HDACi 4b, beginning after the onset of motor deficits, significantly improved motor performance, overall appearance, and body weight of symptomatic R6/2(300Q) transgenic mice. These effects were associated with significant attenuation of gross brain-size decline and striatal atrophy. Microarray studies revealed that HDACi 4b treatment ameliorated, in part, alterations in gene expression caused by the presence of mutant huntingtin protein in the striatum, cortex, and cerebellum of R6/2(300Q) transgenic mice. For selected genes, HDACi 4b treatment reversed histone H3 hypoacetylation observed in the presence of mutant huntingtin, in association with correction of mRNA expression levels. These findings suggest that HDACi 4b, and possibly related HDAC inhibitors, may offer clinical benefit for HD patients and provide a novel set of potential biomarkers for clinical assessment.
Minocycline versus Doxycycline in the Treatment of Acne vulgaris (1978)

16 patients with acne vulgaris were treated with either minocycline or doxycycline. Both drugs appear to have about the same effect when given for 3 months.
Unique oligonucleotide primers in PCR for identification of Cryptococcus neoformans (1994)

On the basis of a comparison of rRNA sequences coding the internal transcribed spacer (ITS) and 5.8S regions of Filobasidiella neoformans, the teleomorph of Cryptococcus neoformans, and members of its most closely related taxa, unique oligonucleotides were designed for the specific amplification of DNA only from C. neoformans. Various combinations of these primers, designated CN4, CN5, and CN6, and the previously described fungal primers ITS1 and ITS2 were tested in PCR for their ability to amplify DNA from 37 strains of C. neoformans and 31 other isolates representing 18 species of yeasts. The combination of primers CN4 and CN5 amplified DNA from both varieties of C. neoformans but from none of the other species tested. Other pairs of primers (namely, CN5-CN6, CN4-ITS1, and CN6-ITS1) amplified DNA only from C. neoformans and from the saprophyte Filobasidiella depauperata, which is the only other member of the genus Filobasidiella. With appropriate controls, these specific oligonucleotides may be used as primers in PCR to identify C. neoformans.
Synthesis of Nitrogen Heterocycles by the Ring Opening of Pyridinium Salts (2006)

The century-old ring-opening reaction of pyridinium salts with tethered nucleophiles has been harnessed for a synthesis of substituted indoles and related nitrogen heterocyles. Extension of this method could lead to oxygen- and sulfur-containing heterocycles and carbocycles, as well as to applications in natural product synthesis and medicinal chemistry.
Effects of Auricular Transcutaneous Electrical Nerve Stimulation on Experimental Pain Threshold (1986)

This study was conducted to examine the effects of high intensity transcutaneous electrical nerve stimulation at auricular acupuncture points on experimental pain threshold. Forty-five healthy adult male and female subjects were assigned randomly to one of two treatment groups or to a control group. Subjects in the two treatment groups received high intensity TENS to either appropriate or inappropriate (placebo) acupuncture points on one ear. Experimental pain threshold at the ipsilateral wrist was determined with a painful electrical stimulus before and after ear stimulation. Only the group receiving stimulation of appropriate ear acupuncture points exhibited a significant increase (p less than .01) in experimental pain threshold after ear stimulation. The comparable placebo and control groups, again, did not exhibit significant pretest-posttest differences in experimental pain threshold. The results suggest that, if applied accurately, auricular TENS can increase pain threshold. Further research is needed to assess the effects of this technique on patient groups.
Click Chemistry: Diverse Chemical Function from a Few Good Reactions (2001)

Examination of nature's favorite molecules reveals a striking preference for making carbon-heteroatom bonds over carbon-carbon bonds-surely no surprise given that carbon dioxide is nature's starting material and that most reactions are performed in water. Nucleic acids, proteins, and polysaccharides are condensation polymers of small subunits stitched together by carbon-heteroatom bonds. Even the 35 or so building blocks from which these crucial molecules are made each contain, at most, six contiguous C-C bonds, except for the three aromatic amino acids. Taking our cue from nature's approach, we address here the development of a set of powerful, highly reliable, and selective reactions for the rapid synthesis of useful new compounds and combinatorial libraries through heteroatom links (C-X-C), an approach we call "click chemistry". Click chemistry is at once defined, enabled, and constrained by a handful of nearly perfect "spring-loaded" reactions. The stringent criteria for a process to earn click chemistry status are described along with examples of the molecular frameworks that are easily made using this spartan, but powerful, synthetic strategy.
Identification of New Fis Binding Sites by DNA Scission with Fis-1,10-phenanthroline−Copper(I) Chimeras (1996)

The chimeric nuclease Fis-OP has been used to identify novel Fis binding sites. Tethering the chemical nuclease OP-Cu+ to position 73 of the protein with a newly developed longer acetyl-beta-alanylamino spacer has facilitated the localization of two high-affinity Fis binding sequences in a 3 kb pUC19 plasmid. The shorter acetamido linker has allowed the chimeric nuclease to locate two strong Fis binding sites in the 50 kb phage lambda genome. All four sites reside in biologically interesting loci and have been confirmed by gel-retardation and DNase I footprint analyses. A newly discovered site resides in the lac operon of Escherichia coli. The binding of Fis to this site may antagonize repression by the LacI repressor. These studies demonstrate the feasibility of applying chimeric chemical nucleases to the task of identifying functional protein binding sites of biological interest within genomes without any assumption about their sequence preference.
Functional properties of nicotinic acetylcholine receptor subunits expressed in various combinations (1987)

The four kinds of subunits of the Torpedo californica nicotinic acetylcholine receptor have been produced in various combinations by injecting Xenopus oocytes with the corresponding subunit-specific mRNAs synthesized by transcription in vitro of the cloned cDNAs. Functional analysis suggests that association of the alpha-subunit with either the gamma- or the delta-subunit is a prerequisite for generating the conformation necessary for agonist binding. The acetylcholine receptor devoid of either the beta-, gamma- or delta-subunit exhibits weak channel activity.
Stereochemistry of the dehydration of 1,2-diphenylpropanols via iodo intermediates (1986)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStereochemistry of the dehydration of 1,2-diphenylpropanols via iodo intermediatesJ. Michael Robinson, Gregory T. Daniel, and Stephanie J. HaleCite this: J. Org. Chem. 1986, 51, 1, 109–111Publication Date (Print):January 1, 1986Publication History Published online1 May 2002Published inissue 1 January 1986https://pubs.acs.org/doi/10.1021/jo00351a027https://doi.org/10.1021/jo00351a027research-articleACS PublicationsRequest reuse permissionsArticle Views570Altmetric-Citations7LEARN 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
Effect of fabrication errors in channel waveguide Bragg gratings (1999)

The spectral performances of nonideal rectangular Bragg gratings, integrated in a rib waveguide, are analyzed by a multilayer approach based on the effective-index method. The effects of errors on the photolithographic definition of the grating, that is, period and shape, and of errors on the control of etching depth are investigated. Also the influence of the stitching error, which is unavoidable when the grating is realized by means of electron-beam photolithography, is addressed. A novel analytical approach that extends coupled-mode theory to the analysis of real gratings is also presented.