gebhart/patrepeval huggingface dataset:
Accuracy and reliability of [11C]PBR28 specific binding estimated without the use of a reference region (2018)

[<sup>11</sup>C]PBR28 is a positron emission tomography radioligand used to examine the expression of the 18 kDa translocator protein (TSPO). TSPO is located in glial cells and can function as a marker for immune activation. Since TSPO is expressed throughout the brain, no true reference region exists. For this reason, an arterial input function is required for accurate quantification of [<sup>11</sup>C]PBR28 binding and the most common outcome measure is the total distribution volume (V<sub>T</sub>). Notably, V<sub>T</sub> reflects both specific binding and non-displaceable binding. Therefore, estimates of specific binding, such as binding potential (e.g. BP<sub>ND</sub>) and specific distribution volume (V<sub>S</sub>) should theoretically be more sensitive to underlying differences in TSPO expression. It is unknown, however, if unbiased and accurate estimates of these outcome measures are obtainable for [<sup>11</sup>C]PBR28. The Simultaneous Estimation (SIME) method uses time-activity-curves from multiple brain regions with the aim to obtain a brain-wide estimate of the non-displaceable distribution volume (V<sub>ND</sub>), which can subsequently be used to improve the estimation of BP<sub>ND</sub> and V<sub>S</sub>. In this study we evaluated the accuracy of SIME-derived V<sub>ND</sub>, and the reliability of resulting estimates of specific binding for [<sup>11</sup>C]PBR28, using a combination of simulation experiments and in vivo studies in healthy humans. The simulation experiments, based on data from 54 unique [<sup>11</sup>C]PBR28 examinations, showed that V<sub>ND</sub> values estimated using SIME were both precise and accurate. Data from a pharmacological competition challenge (n = 5) showed that SIME provided V<sub>ND</sub> values that were on average 19% lower than those obtained using the Lassen plot, but similar to values obtained using the Likelihood-Estimation of Occupancy technique. Test-retest data (n = 11) showed that SIME-derived V<sub>S</sub> values exhibited good reliability and precision, while larger variability was observed in SIME-derived BP<sub>ND</sub> values. The results support the use of SIME for quantifying specific binding of [<sup>11</sup>C]PBR28, and suggest that V<sub>S</sub> can be used in complement to the conventional outcome measure V<sub>T</sub>. Additional studies in patient cohorts are warranted.
Make This! Introduction to Electronics Prototyping Using Arduino (2019)

This course is a hands-on introduction to interactive electronics prototyping for people with a variety of backgrounds, including those with no prior experience in electronics. Familiarity with programming is helpful, but not required. Participants learn basic electronics, microcontroller programming and physical prototyping using the Arduino platform, then use digital and analog sensors, LED lights and motors to build, program and customize a small paper robot.
Phase Equilibrium and Martensitic Transformation in Lanthana‐Doped Zirconia (1988)

The system ZrO 2 ‐La 2 O 3 has been studied in the 0 to 15 mol% La 2 O 3 range using X‐ray diffraction and thermal analysis. Two kinds of diagrams were elaborated: First is a phase equilibrium diagram where the eutectoid decomposition of ZrO 2, ss (T) → ZrO 2, ss (M) + Py ss occurs at 1100°C and 0.75 mol% La 2 O 3 (Py is the pyrochlore compound Zr 2 La 2 O 7 ). The maximum solubility of La 2 O 3 in ZrO 2, ss (M) is 0.5 mol% at room temperature. Second, a nonequilibrium diagram is determined showing the correlations between grain size, La 2 O 3 content, and the martensitic transformation temperature start ( Ms ).
Controlling the Physical Dimensions of Peptide Nanotubes by Supramolecular Polymer Coassembly (2016)

Molecular self-assembly of peptides into ordered nanotubes is highly important for various technological applications. Very short peptide building blocks, as short as dipeptides, can form assemblies with unique mechanical, optical, piezoelectric, and semiconductive properties. Yet, the control over nanotube length in solution has remained challenging, due to the inherent sequential self-assembly mechanism. Here, in line with polymer chemistry paradigms, we applied a supramolecular polymer coassembly methodology to modulate peptide nanotube elongation. Utilizing this approach, we achieved a narrow, controllable nanotube length distribution by adjusting the molecular ratio of the diphenylalanine assembly unit and its end-capped analogue. Kinetic analysis suggested a slower coassembly organization process as compared to the self-assembly dynamics of each of the building blocks separately. This is consistent with a hierarchal arrangement of the peptide moieties within the coassemblies. Mass spectrometry analysis demonstrated the bimolecular composition of the coassembled nanostructures. Moreover, the peptide nanotubes' length distribution, as determined by electron microscopy, was shown to fit a fragmentation kinetics model. Our results reveal a simple and efficient mechanism for the control of nanotube sizes through the coassembly of peptide entities at various ratios, allowing for the desired end-product formation. This dynamic size control offers tools for molecular engineering at the nanoscale exploiting the advantages of molecular coassembly.
Research Resource: Whole Transcriptome RNA Sequencing Detects Multiple 1α,25-Dihydroxyvitamin D3-Sensitive Metabolic Pathways in Developing Zebrafish (2012)

The biological role of vitamin D receptors (VDR), which are abundantly expressed in developing zebrafish (Danio rerio) as early as 48 h after fertilization, and before the development of a mineralized skeleton and mature intestine and kidney, is unknown. We probed the role of VDR in developing zebrafish biology by examining changes in expression of RNA by whole transcriptome shotgun sequencing (RNA-seq) in fish treated with picomolar concentrations of the VDR ligand and hormonal form of vitamin D(3), 1α,25-dihydroxyvitamin D(3) [1α,25(OH)(2)D(3))].We observed significant changes in RNAs of transcription factors, leptin, peptide hormones, and RNAs encoding proteins of fatty acid, amino acid, xenobiotic metabolism, receptor-activator of NFκB ligand (RANKL), and calcitonin-like ligand receptor pathways. Early highly restricted, and subsequent massive changes in more than 10% of expressed cellular RNA were observed. At days post fertilization (dpf) 2 [24 h 1α,25(OH)(2)D(3)-treatment], only four RNAs were differentially expressed (hormone vs. vehicle). On dpf 4 (72 h treatment), 77 RNAs; on dpf 6 (120 h treatment) 1039 RNAs; and on dpf 7 (144 h treatment), 2407 RNAs were differentially expressed in response to 1α,25(OH)(2)D(3). Fewer RNAs (n = 481) were altered in dpf 7 larvae treated for 24 h with 1α,25(OH)(2)D(3) vs. those treated with hormone for 144 h. At dpf 7, in 1α,25(OH)(2)D(3)-treated larvae, pharyngeal cartilage was larger and mineralization was greater. Changes in expression of RNAs for transcription factors, peptide hormones, and RNAs encoding proteins integral to fatty acid, amino acid, leptin, calcitonin-like ligand receptor, RANKL, and xenobiotic metabolism pathways, demonstrate heretofore unrecognized mechanisms by which 1α,25(OH)(2)D(3) functions in vivo in developing eukaryotes.
[Allogenic transplantation of sterilised bones and halfjoints (author's transl)]. (1978)

The bones and halfjoints were gained under non-sterile conditions. They were sterilised using 1% formaldehyde solution and preserved with 2% formaldehyde--sugar solution or 50% honey solution. 102 allogenic transplants were performed in 100 patients. The results are very satisfying. The method described is effective, of universal practicability and guarentees constant available high class bone material for transplantation.
Comparison of Uniform and Non-Uniform SIW CRLH LW antennas (2019)

This paper presents the results and investigation of substrate integrated waveguide (SIW) leaky-wave antenna (LWA) based on the composite right/left-handed (CRLH) structure designed for X band applications. The interest is given to two antenna types: uniform CRLH antenna, non-uniform CRLH antenna where three balanced CRLH unit cells are used in the design. Results of both structures show that a wide scanning range over the frequency bandwidth from 9 to 13.4 GHz is obtained. The side lobe level is remarkably decreased in the non-uniform structure especially around the broadside area which is suitable for many scanning applications.
Steric and Hydrogen-Bonding Effects on the Stability of Copper Complexes with Small Molecules (2004)

A series of the copper(II) complexes with tripodal tetradentate tris(pyridyl 2-methyl)amine-based ligands possessing the hydrogen-bonding 6-aminopyridine units (tapa, three amino groups; bapa, two amino groups; mapa, one amino group) have been synthesized, and their copper(II) complexes with a small molecule such as dioxygen and azide have been studied spectroscopically and structurally. The reaction of their Cu(II) complexes with NaN(3) have given the mononuclear copper complexes with azide in an end-on mode, [Cu(tapa)(N(3))]ClO(4) (1a), [Cu(bapa)(N(3))]ClO(4) (2a), [Cu(mapa)(N(3))]ClO(4) (3a), and [Cu(tpa)(N(3))]ClO(4) (4a) (tpa, no amino group). The crystal structures have revealed that the coordination geometries around the metal centers are almost a trigonal-bipyramidal rather than a square-planar except for 1a with an intermediate between them. The UV-vis and ESR spectral data indicate that the increase of NH(2) groups of ligands causes the structural change from trigonal-bipyramidal to square-pyramidal geometry, which is regulated by a combination of steric repulsion and hydrogen bond. The steric repulsion of amino groups with the azide nitrogen gives rise to elongation of the Cu-N(py) bonds, which leads to the positive shift of the redox potentials of the complexes. The hydrogen bonds between the coordinated azide and amino nitrogens (2.84-3.05 A) contribute clearly to the fixation of azide. The Cu(I) complexes with bapa and mapa ligands have been obtained as a precipitate, although that with tapa was not isolated. The reactions of the Cu(I) complexes with dioxygen in MeOH at -75 degrees C have given the trans-micro-1,2 peroxo dinuclear Cu(II) complexes formulated as [((tapa)Cu)(2)(O(2))](2+) (1c), [((bapa)Cu)(2)(O(2))](2+) (2c), and [((mapa)Cu)(2)(O(2))](2+) (3c), whose characterizations were confirmed by UV-vis, ESR, and resonance Raman spectroscopies. UV-vis spectra of 1c, 2c, and 3c exhibited intense bands assignable to pi(O(2)(2)(-))-to-d(Cu) charge transfer (CT) transitions at lambda(max)/nm (epsilon/M(-1)cm(-1)) = 449 (4620), 474 (6860), and 500 (9680), respectively. The series of the peroxo adducts generated was ESR silent. The resonance Raman spectra exhibited the enhanced features assignable to two stretching vibrations nu((16)O-(16)O/(18)O-(18)O)/cm(-1) and nu(Cu-(16)O/Cu-(18)O)/cm(-1) at 853/807 (1c), 858/812 (2c), 847/800 (3c), and at 547/522 (2c), 544/518 (3c), respectively. The thermal stability of the peroxo-copper species has increased with increase in the number of the hydrogen-bonding interactions between the peroxide and amino groups.
Vortex Loops and Majorana Fermions (2013)

Abstract: We investigate the role that vortex loops play in characterizing eigen-states of certain systems of half-integer spins with nearest-neighbor interaction on a trivalent lattice. In particular we focus on ground states (and other low-lying states). We test our ideas on a “spin ladder. ” In certain cases we show how the vortex configuration of the ground state is determined by the relative signs of the coupling constants. Two methods yield exact results: i.) We utilize the equiv-alence of spin Hamiltonians with quartic interactions of Majorana fermions, and analyze that fermionic Hamiltonian. ii) We use reflection positivity for Majorana fermions to characterize vortices in ground states for reflection-symmetric cou-plings. Two additional methods suggest potential wider applicability of these results: iii.) Numerical evidence suggests similar behavior for certain systems without reflection symmetry. iv.) A perturbative analysis also suggests similar behavior without the assumption of reflection symmetry. I.
Isolation of Su(var)3-7 Mutations by Homologous Recombination in Drosophila melanogaster (2002)

The Su(var)3-7 gene, a haplo-suppressor and triplo-enhancer of position-effect variegation (PEV), encodes a zinc finger heterochromatin-associated protein. To understand the role of this protein in heterochromatin and genomic silencing, mutations were generated by homologous recombination. The donor fragment contained a yellow(+) gene and 7.6 kb of the Su(var)3-7 gene inserted between two FRTs. The Su(var)3-7 sequence contained three stop codons flanking an I-SceI cut site located in the 5' half of the gene. Using two different screening approaches, we obtained an allelic series composed of three mutant alleles. The three mutations are dominant suppressors of PEV. One behaves as a null mutation and results in a maternal-effect recessive lethal phenotype that can be rescued by a zygotic paternal wild-type gene. A P transposon zygotically expressing a Su(var)3-7 full-length cDNA also rescues the mutant phenotype. One hypomorphic allele is viable and the pleiotropic phenotype showed by adult flies indicates that rapidly and late dividing cells seem the most affected by reduced amounts of Su(var)3-7 protein. All three mutants were characterized at the molecular level. Each expresses a portion of the Su(var)3-7 protein that is unable to enter the nucleus and bind chromatin.
Measles-Mumps-Rubella Vaccine and Autistic Spectrum Disorder: Report From the New Challenges in Childhood Immunizations Conference Convened in Oak Brook, Illinois, June 12–13, 2000 (2001)

Although the possible association with MMR vaccine has received much public and political attention and there are many who have derived their own conclusions based on personal experiences, the available evidence does not support the hypothesis that MMR vaccine causes autism or associated disorders or IBD. Separate administration of measles, mumps, and rubella vaccines to children provides no benefit over administration of the combination MMR vaccine and would result in delayed or missed immunizations. Pediatricians need to work with families to ensure that children are protected early in the second year of life from these preventable diseases. Continued scientific efforts need to be directed to the identification of the causes of ASD.
Novel Approach to 5‐Substituted Proline Derivatives Using a Silver‐Catalyzed Cyclization as the Key Step. (2005)

Abstract For Abstract see ChemInform Abstract in Full Text.
Phosphatidylcholine Hydrolysis by Phospholipase D Determines Phosphatidate and Diglyceride Levels in Chemotactic Peptide-stimulated Human Neutrophils (1989)

Human neutrophils have been labeled in 1-O-alkyl-phosphatidylcholine (alkyl-PC) with 32P by incubation with alkyl-[32P]lysoPC. Upon stimulation with the chemotactic peptide, formylMet-Leu-Phe (fMLP), these 32P-labeled cells produce 1-O-alkyl-[32P]phosphatidic acid (alkyl-[32P]PA) and, in the presence of ethanol, 1-O-alkyl-[32P]phosphatidylethanol (alkyl-[32P]PEt). Because the cellular ATP contains no 32P, alkyl-[32P]PA and alkyl-[32P]PEt must be formed from alkyl-[32P]PC by phospholipase D (PLD)-catalyzed hydrolysis and transphosphatidylation, respectively. Analyses of the sn-1 bonds by selective hydrolysis and mass measurements reveal that the PA and PEt formed during stimulation contain both ester and ether bonds with distributions similar to that in the endogenous PC. Furthermore, in neutrophils labeled in alkyl-[32P]PC, the specific activities of the diradyl-PA and diradyl-PEt formed during stimulation are similar to that of diradyl-PC. These results demonstrate that the fMLP-induced PLD utilizes diradyl-PC as the major substrate. It is further concluded that, at early times (30 s), PA and PEt are both formed almost exclusively by PLD. Following stimulation with fMLP, neutrophils double-labeled in alkyl-PC by incubation with [3H]alkyl-lysoPC and alkyl-[32P]lysoPC generate [3H]alkyl-DG and [32P]orthophosphate [( 32P]PO4) with superimposable kinetics, indicating degradation of PA by a phosphohydrolase. Generation of [3H]alkyl-DG and [32P]PO4 lags behind PA formation and parallels the decline in PA accumulation. In addition, generation of both [3H]alkyl-PA and [3H]alkyl-DG requires extracellular Ca2+ and cytochalasin B. Furthermore, the phosphohydrolase inhibitor, propranolol, decreases both [3H]alkyl-DG and [32P]PO4 while increasing [3H]alkyl-PA and not altering [3H]alkyl-PEt. Moreover, the decreases in DG are accounted for by increases in PA. These results demonstrate that PLD-derived alkyl-PA is degraded by a phosphohydrolase to produce alkyl-DG. DG formed during stimulation contains both ester and ether-linked species and this DG formation is inhibited completely by propranolol. Upon stimulation, alkyl-[32P]PC-labeled neutrophils do not produce [32P]phosphocholine, suggesting that PC is not hydrolyzed by phospholipase C. In addition, PA is formed in amounts sufficient to account for all of the DG formed during stimulation. It is concluded that the DG formed during fMLP stimulation is derived almost exclusively from PC via the PLD/PA phosphohydrolase pathway.
Mutagenicity and chemistry of N-nitroso-N-(parasubstituted-benzyl)methylamines (1983)

The relative mutagenicities of N-nitroso-N-(p-substituted-benzyl)methylamines in Salmonella typhimurium TA 1535 were tested in order to determine whether biological activity is affected by the electron density at a nitrosamine alpha carbon. The order of potency was as follows: X = Cl greater than CN greater than Br greater than NO2 greater than H greater than CH3O greater than CH3 greater than F much greater than COOH. No direct correlation was apparent, nor was there any obvious correlation between biological activity and the extent of base-catalyzed hydrogen-deuterium exchange at the alpha carbons.
Rhenium(VII) monoimido alkylidene complexes: synthesis, structure, and Lewis-acid-cocatalyzed olefin metathesis (1991)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRhenium(VII) monoimido alkylidene complexes: synthesis, structure, and Lewis-acid-cocatalyzed olefin metathesisMark H. Schofield, Richard R. Schrock, and Lee Y. ParkCite this: Organometallics 1991, 10, 6, 1844–1851Publication Date (Print):June 1, 1991Publication History Published online1 May 2002Published inissue 1 June 1991https://pubs.acs.org/doi/10.1021/om00052a034https://doi.org/10.1021/om00052a034research-articleACS PublicationsRequest reuse permissionsArticle Views262Altmetric-Citations31LEARN 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-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Growth and Properties of Doped Scandia Crystals (2007)

Single crystals of Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> and Ln:Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> (Ln = Er, Yb, Ho, Tm) have been synthesized hydrothermally. Some initial spectroscopic properties of these interesting materials are discussed.
Comparison between the classical theory predictions and molecular simulation results for heterogeneous nucleation of argon (2006)

We have performed Monte Carlo simulations of homogeneous and heterogeneous nucleations of Lennard-Jones argon clusters. The simulation results were interpreted using the major concept posing a difference between the homogeneous and heterogeneous classical nucleation theories-the contact parameter. Our results show that the multiplication concept of the classical heterogeneous nucleation theory describes the cluster-substrate interaction surprisingly well even for small molecular clusters. However, in the case of argon nucleating on a rigid monolayer of fcc(111) substrate at T=60 K, the argon-substrate atom interaction being approximately one-third as strong as the argon-argon interaction, the use of the classical theory concept results in an underestimation of the heterogeneous nucleation rate by two to three orders of magnitude even for large clusters. The main contribution to this discrepancy is induced by the failure of the classical theory of homogeneous nucleation to predict the energy involved in bringing one molecule from the vapor to the cluster for clusters containing less than approximately 15 molecules.
Transcriptomic Changes Induced by Deletion of Transcriptional Regulator GCR2 on Pentose Sugar Metabolism in Saccharomyces cerevisiae (2021)

Being a microbial host for lignocellulosic biofuel production, <i>Saccharomyces cerevisiae</i> needs to be engineered to express a heterologous xylose pathway; however, it has been challenging to optimize the engineered strain for efficient and rapid fermentation of xylose. Deletion of <i>PHO13</i> (Δ<i>pho13</i>) has been reported to be a crucial genetic perturbation in improving xylose fermentation. A confirmed mechanism of the Δ<i>pho13</i> effect on xylose fermentation is that the Δ<i>pho13</i> transcriptionally activates the genes in the non-oxidative pentose phosphate pathway (PPP). In the current study, we found a couple of engineered strains, of which phenotypes were not affected by Δ<i>pho13</i> (Δ<i>pho13</i>-negative), among many others we examined. Genome resequencing of the Δ<i>pho13</i>-negative strains revealed that a loss-of-function mutation in <i>GCR2</i> was responsible for the phenotype. Gcr2 is a global transcriptional factor involved in glucose metabolism. The results of RNA-seq confirmed that the deletion of <i>GCR2</i> (Δ<i>gcr2</i>) led to the upregulation of PPP genes as well as downregulation of glycolytic genes, and changes were more significant under xylose conditions than those under glucose conditions. Although there was no synergistic effect between Δ<i>pho13</i> and Δ<i>gcr2</i> in improving xylose fermentation, these results suggested that <i>GCR2</i> is a novel knockout target in improving lignocellulosic ethanol production.