gebhart/patrepeval huggingface dataset:
Synthesis and biological properties of purine and pyrimidine 5'-deoxy-5'-(dihydroxyphosphinyl)-.beta.-D-ribofuranosyl analogs of AMP, GMP, IMP, and CMP (1989)

Methyl 2,3-O-isopropylidene-D-ribofuranoside (1) was converted to 1-O-acetyl-5-bromo-5-deoxy-2,3-di-O-benzoyl-D-ribofuranose (6) in five steps with good yield. The Arbuzov condensation of compound 6 with triethyl phosphite resulted in the synthesis of 1-O-acetyl-2,3-di-O-benzoyl-5-deoxy-5-(diethoxyphosphinyl)-D-ribofuranos e (7). Compound 7 was used for direct glycosylation of both purine and pyrimidine bases. The glycosylation was accomplished with the dry silylated heterocyclic base in the presence of trimethylsilyl triflate. Deblocking of the glycosylation products gave exclusively the beta anomer of the 5'-phosphonate analogues of 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]adenine (13), 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]guanosin e (16), 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]hypoxant hine (17), and 9-[5'-deoxy-5'-(dihydroxyphosphinyl)-beta-D-ribofuranosyl]cytosine (15), described here for the first time. The target compounds as well as their intermediates showed no in vitro antiviral or antitumor activity, although phosphorylation of 15 and 16 to di- and triphosphate analogues was demonstrated with use of isolated cellular enzymes.
Nephrectomy for advanced ureteral hypoplasia accompanied by renal dysplasia in a patient with congenital hydronephrosis: A case report (2018)

The patient was an 8-month-old girl. Her prenatal ultrasonography at 26 weeks of gestation revealed an abdominal cystic lesion. After birth, the patient was diagnosed with left hydronephrosis and referred to our hospital. Ultrasonography showed grade IV hydronephrosis in the left kidney. MAG3 scintigraphy showed no function in the left kidney. Cystoscopic retrograde pyeloureterography revealed advanced stenosis throughout the entire length of the left ureter. For intraoperative finings, the ureter was extremely thin with 2.6 mm outer diameter and the renal parenchyma was mostly scarred. Since it was difficult to place a stent in the ureter, nephrectomy was performed. For pathological findings, fibrosis with cartilage tissue in the residual renal parenchyma was observed and renal dysplasia was confirmed. Nephrectomy should be considered for advanced ureteral hypoplasia in patients with the entire ureteral hypoplasia because the diseased kidney is often accompanied by dysplasia or severe hypoplasia.
Metallocene catalysts for olefin polymerizations. XXIV. Stereoblock propylene polymerization catalyzed by <i>rac</i>‐[<i>anti</i>‐ethylidene(1‐η<sup>5</sup>‐tetramethylcyclopentadienyl)(1‐η<sup>5</sup>‐indenyl)dimethyltitanium: A two‐state propagation (1992)

Abstract Racemic‐ anti ‐[ethylidene(1‐η 5 ‐tetramethylcyclopentadienyl) (1‐η 5 ‐indenyl)dimethyltitanium ( 6 ) has been synthesized and its molecular structure determined by x‐ray diffraction methods. The two TiMe(1) and TiMe(2) units have bond distances differing by 0.08 Å and their proton NMR resonances are separated by over 1 ppm. Using this compound and methylaluminoxane (MAO) as the activator, at 25°C the 6 /MAO catalyst produced polypropylene having crystalline domain with physical crosslinks. The polymers obtained at lower polymerization temperatures are rheologically liquids. The behaviors of this catalyst system resembles closely the previously reported rac ‐[ anti ‐ethylidene(1‐η 5 ‐tetramethylcyclopentadienyl) (1‐η 5 ‐indenyl)dichlorotitanium ( 4 )/MAO system. The structure of 6 determined here furnishes tangible support for the proposed two‐state (isomeric)‐switching propagation mechanism. Addition of MAO to 6 causes broadening of the Me(1) resonance in the 1 H‐NMR spectra, and 6 is decomposed by Ph 3 C + B(C 6 F 5 ) ‐ 4 . © 1992 John Wiley & Sons, Inc.
Estimating the contribution of studies in network meta-analysis: paths, flows and streams (2018)

In network meta-analysis, it is important to assess the influence of the limitations or other characteristics of individual studies on the estimates obtained from the network. The proportion contribution matrix, which shows how much each direct treatment effect contributes to each treatment effect estimate from network meta-analysis, is crucial in this context. We use ideas from graph theory to derive the proportion that is contributed by each direct treatment effect. We start with the 'projection' matrix in a two-step network meta-analysis model, called the <i><b>H</b></i> matrix, which is analogous to the hat matrix in a linear regression model. We develop a method to translate <b><i>H</i></b> entries to proportion contributions based on the observation that the rows of <b><i>H</i></b> can be interpreted as flow networks, where a stream is defined as the composition of a path and its associated flow. We present an algorithm that identifies the flow of evidence in each path and decomposes it into direct comparisons. To illustrate the methodology, we use two published networks of interventions. The first compares no treatment, quinolone antibiotics, non-quinolone antibiotics and antiseptics for underlying eardrum perforations and the second compares 14 antimanic drugs. We believe that this approach is a useful and novel addition to network meta-analysis methodology, which allows the consistent derivation of the proportion contributions of direct evidence from individual studies to network treatment effects.
Low Print-Through Technology With Rare Earth Tantalate Phosphors (1985)

Fundamental properties of the family of rare earth tantalate phosphors are reviewed, including crystal structure, morphology, density and luminescence. Ultraviolet emitting YTa0A becomes a good choice for commercial applications, based on low print-through with double emulsion films, high DQE and high sharpness to speed ratio. Speed, DQE and MTF data for Quanta Detail and Quanta Fast Detail screens made from YTaO4 are presented.
<title>FaceTrack: tracking and summarizing faces from compressed video</title> (1999)

In this paper, we present FaceTrack, a system that detects, tracks, and groups faces from compressed video data. We introduce the face tracking framework based on the Kalman filter and multiple hypothesis techniques. We compare and discuss the effects of various motion models on tracking performance. Specifically, we investigate constant-velocity, constant-acceleration, correlated-acceleration, and variable-dimension-filter models. We find that constant- velocity and correlated-acceleration models work more effectively for commercial videos sampled at high frame rates. We also develop novel approaches based on multiple hypothesis techniques to resolving ambiguity issues. Simulation results show the effectiveness of the proposed algorithms on tracking faces in real applications.
Combined high-pressure cell–ultrahigh vacuum system for fast testing of model metal alloy catalysts using scanning mass spectrometry (2004)

An apparatus for fabrication, surface analysis in ultrahigh vacuum, and testing of the catalytic activity of model metal alloy catalysts is described. Arrays of model catalysts are produced by electron-beam deposition of up to four metals simultaneously onto a substrate. The surface analysis techniques available are scanning electron microscopy, x-ray photoemission spectroscopy, ion scattering spectroscopy, Auger electron spectroscopy, sputter profiling, and temperature programmed desorption. The catalytic activity of the model catalysts is tested individually by scanning a combined gas delivery and gas sampling device over the sample surface. The gas sampled is analyzed with mass spectrometry. Experiments can be made at pressures up to 1 bar and temperatures up to 500 °C. It is shown that the lateral resolution is better than 0.2 mm and that up to 20 circular spots, 1 mm in diameter, can be studied on a substrate 10 mm in diameter. A high pressure cell with an all-metal sealed ultrahigh vacuum lock is also described as part of the work.
A novel N6-methyladenosine (m6A)-dependent fate decision for the lncRNA THOR (2020)

Previous studies have revealed the critical roles of the N6-methyladenosine (m6A) modification of long non-coding RNAs (lncRNAs) in cancers, but the relationship between the oncogenic role of the lncRNA THOR (a representative of cancer/testis lncRNAs) and m6A modification remains unclear. Here, we show that the internal m6A modification of the lncRNA THOR via an m6A-reader-dependent modality regulates the proliferation of cancer cells. Our findings demonstrated that the loss of the lncRNA THOR inhibits the proliferation, migration, and invasion of cancer cells in vitro and in vivo. In addition, m6A is highly enriched on lncRNA THOR transcripts, which contain GA (m6A) CA, GG (m6A) CU, and UG (m6A) CU sequence motifs. RIP-qRT-PCR and RNA pull-down assay results revealed that the specific m6A readers YTHDF1 and YTHDF2 can read the m6A motifs and regulate the stability of the lncRNA THOR (stabilization and decay). These m6A-dependent RNA-protein interactions can maintain the oncogenic role of the lncRNA THOR. Collectively, these findings highlight the critical role of the m6A modification in oncogenic lncRNA THOR and reveal a novel long non-coding RNA regulatory mechanism, providing a new way to explore RNA epigenetic regulatory patterns in the future.
Analyzing novice programmers' response to compiler error messages (2016)

Error messages represent a critical feedback mechanism provided to introductory programming students during their early attempts at programming. However, these messages are explanations of program-translation problems, rather than true feedback on mistakes in a students program. This mismatch presents problems for novices, while experts are able to make more appropriate use of compiler error messages. Programming activity logs generated by an instructional programming environment were analyzed for students' utilization of error messages in their edits prior to each compilation. Overall, students addressed the first error about half the time. Assignment grades were positively associated with the proportion of times that the first error message was addressed.
Lattice dynamics, random walks, and nonintegral effective dimensionality (1982)

Definitions of the nonintegral effective dimensionality of recursively defined lattices (fractal lattices) may be based on scaling properties of the lattices, or on the qualitative behavior of cooperative phenomena supported by the lattices. We examine analogs of these definitions for regular (i.e., periodic) lattices supporting long-range interactions. In particular, we show how to calculate a harmonic oscillator effective dimension, a scaling dimension, and a random walk effective dimension for simple cubic lattices with a class of long-range interactions. We examine the relationship between these three dimensions for regular lattices, and conjecture a constraint on the analogs of these dimensions for fractal lattices.
An Empirical Study of Block Matching Techniques for the Detection of Moving Objects (2006)

The basis of surveillance, event detection, and tracking applications is the detection of moving objects in complex scenes. Complex scenes are difficult to analyze because of camera noise and lighting conditions. Currently, moving objects are detected primarily using background subtraction. We analyze block matching as an alternative for detecting moving objects. Block matching has been extensively utilized in compression algorithms for motion estimation. Besides detection of moving objects, block matching also provides motion vectors (location of motion) which can aide in tracking objects. Block matching techniques consist of three main components: block determination, search methods, and matching criteria. We compare various options for each of the components with moving object detection as the performance goal. Publicly available sequences of several different traffic and weather conditions are used to evaluate the techniques. A coherence metric and the average magnitude of object motion vector error are used to evaluate block determination approaches and search methods. To compare the matching criteria we use precision-recall curves to evaluate the performance of motion detection. We present an empirical study of the block matching techniques using these metrics of performance as well as process timing. We found the hierarchical block determination approach has an overall higher coherence of object motion vectors than the simple block determination approach, but with a significant increase in process timing. The average magnitude of object motion vector for the search methods evaluated were comparable, with the cross search method having a better coherence of object motion vectors. Overall the three step search (TSS) detects more moving objects than the cross and 2D-logarithmic search methods. And the mean square difference (MSD) matching criterion has the best precision-recall as well as process timing when using zero motion biasing.
The Toxic Effects of Amines (1928)

Journal Article The Toxic Effects of Amines Get access A. R. Johnston A. R. Johnston From the Eichberg Laboratory of Physiology of the University of Cincinnati, Cincinnati, Ohio Search for other works by this author on: Oxford Academic PubMed Google Scholar The Journal of Infectious Diseases, Volume 42, Issue 5, May 1928, Pages 473–484, https://doi.org/10.1093/infdis/42.5.473 Published: 01 May 1928 Article history Received: 15 December 1927 Published: 01 May 1928
Minimum mean square equalization in cyclostationary and stationary interference-analysis and subscriber line calculations (1991)

Equalization in cyclostationary interference, which occurs when similar neighboring digital communication systems cause interference (crosstalk), is considered. An expression is derived on the minimum mean square performance of a continuous-time infinite-length decision feedback equalizer in the presence of multiple cyclostationary interferers and additive white noise. This expression is calculated for a subscriber line system to show the performance improvements over the situation where the interference is stationary with the same power spectrum. Linear equalizer performance curves were also added to the comparisons. These results show two techniques which can provide opportunities for improved equalizer performance by enhancing the cyclostationarity of the interference. The first is by decreasing the misalignment of the phases of the transceiver clocks in the central office transmitters. The second is by using transmitter pulse bandwidths which are wide relative to the symbol rate.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Expression of the novel mitoxantrone resistance associated gene MXR7 in colorectal malignancies. (1998)

It was shown previously that a glypican encoding gene (MXR7/GPC3/OCl-5) was associated with mitoxantrone resistance in vitro. This study describes and investigation of an association between multidrug resistance and MXR7 in surgical cryo-specimens of 51 gastrointestinal tumors. The mRNA expression levels differ widely according to tumor species. In primary colorectal cancers, the level of MXR7 mRNA expression correlated loosely with the mRNA expression level of the multidrug-resistance-associated protein (MRP). In colorectal metastases an elevated MXR7 mRNkA expression level was observed when compared to primary colorectal carcinomas.
Intracellular Distribution of Fluorescent Copper and Zinc Bis(thiosemicarbazonato) Complexes Measured with Fluorescence Lifetime Spectroscopy (2015)

The intracellular distribution of fluorescently labeled copper and zinc bis(thiosemicarbazonato) complexes was investigated in M17 neuroblastoma cells and primary cortical neurons with a view to providing insights into the neuroprotective activity of a copper bis(thiosemicarbazonato) complex known as Cu(II)(atsm). Time-resolved fluorescence measurements allowed the identification of the Cu(II) and Zn(II) complexes as well as the free ligand inside the cells by virtue of the distinct fluorescence lifetime of each species. Confocal fluorescent microscopy of cells treated with the fluorescent copper(II)bis(thiosemicarbazonato) complex revealed significant fluorescence associated with cytoplasmic puncta that were identified to be lysosomes in primary cortical neurons and both lipid droplets and lysosomes in M17 neuroblastoma cells. Fluorescence lifetime imaging microscopy confirmed that the fluorescence signal emanating from the lipid droplets could be attributed to the copper(II) complex but also that some degree of loss of the metal ion led to diffuse cytosolic fluorescence that could be attributed to the metal-free ligand. The accumulation of the copper(II) complex in lipid droplets could be relevant to the neuroprotective activity of Cu(II)(atsm) in models of amyotrophic lateral sclerosis and Parkinson's disease.
Cannabinoids inhibit N-type calcium channels in neuroblastoma-glioma cells. (1992)

The psychoactive properties of Cannabis sativa and its major biologically active constituent, delta 9-tetrahydrocannabinol, have been known for years. The recent identification and cloning of a specific cannabinoid receptor suggest that cannabinoids mimic endogenous compounds affecting neural signals for mood, memory, movement, and pain. Using whole-cell voltage clamp and the cannabinomimetic aminoalkylindole WIN 55,212-2, we have found that cannabinoid receptor activation reduces the amplitude of voltage-gated calcium currents in the neuroblastoma-glioma cell line NG108-15. The inhibition is potent, being half-maximal at less than 10 nM, and reversible. The inactive enantiomer, WIN 55,212-3, does not reduce calcium currents even at 1 microM. Of the several types of calcium currents in NG108-15 cells, cannabinoids predominantly inhibit an omega-conotoxin-sensitive, high-voltage-activated calcium current. Inhibition was blocked by incubation with pertussis toxin but was not altered by prior treatment with hydrolysis-resistant cAMP analogues together with a phosphodiesterase inhibitor, suggesting that the transduction pathway between the cannabinoid receptor and calcium channel involves a pertussis toxin-sensitive GTP-binding protein and is independent of cAMP metabolism. However, the development of inhibition is considerably slower than a pharmacologically similar pathway used by an alpha 2-adrenergic receptor in these cells. Our results suggest that inhibition of N-type calcium channels, which could decrease excitability and neurotransmitter release, may underlie some of the psychoactive effects of cannabinoids.
Film formation from pigmented latex systems: Drying kinetics and bulk morphologies of ground calcium carbonate/functionalized poly(<i>n</i>‐butyl methacrylate‐<i>co</i>‐<i>n</i>‐butyl acrylate) blend films (2006)

Abstract The drying kinetics and bulk morphology of pigmented latex films obtained from poly( n ‐butyl methacrylate‐ co ‐ n ‐butyl acrylate) latex particles functionalized with carboxyl groups and ground calcium carbonate blends were studied. Latex/pigment blends with higher carboxyl group coverage on the latex particle surfaces dried faster than films with few or no carboxyl groups present. The latex/pigment dispersions also dried faster when there was more stabilizer present in the blend system because of the hydrophilic nature of the stabilizer. The net effect of increasing the pigment volume concentration in the blend system was to shorten the drying time. The bulk morphologies of the freeze‐fractured surfaces of the pigmented latex films were studied with scanning electron microscopy. Scanning electron microscopy analysis showed that increased surface coverage of carboxyl groups on the latex particles in the latex/pigment blends resulted in the formation of smaller pigment aggregates with a more uniform size distribution in the blend films. In addition, the use of smaller latex particles in the blends reduced the ground calcium carbonate pigment aggregate size in the resulting films. Scanning electron microscopy analysis also showed that when the initial stabilizer coverage on the latex particles was equal to 18%, smaller aggregates of ground calcium carbonate were distributed within the copolymer matrix of the blend films in comparison with the cases for which the initial stabilizer coverage on the latex particles was 8 or 36%. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2267–2277, 2006
V<sub>2</sub>O<sub>5</sub> Nanowires with an Intrinsic Peroxidase‐Like Activity (2010)

Abstract V 2 O 5 nanowires exhibit an intrinsic catalytic activity towards classical peroxidase substrates such as 2,2‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) and 3,3,5,5,‐tetramethylbenzdine (TMB) in the presence of H 2 O 2 . These V 2 O 5 nanowires show an optimum reactivity at a pH of 4.0 and the catalytic activity is dependent on the concentration. The Michaelis‐Menten kinetics of the ABTS oxidation over these nanowires reveals a behavior similar to that of their natural vanadium‐dependent haloperoxidase (V‐HPO) counterparts. The V 2 O 5 nanowires mediate the oxidation of ABTS in the presence of H 2 O 2 with a turnover frequency ( k cat ) of 2.5 × 10 3 s −1 . The K M values of the V 2 O 5 nanowires for ABTS oxidation (0.4 μ M ) and for H 2 O 2 (2.9 μ M ) at a pH of 4.0 are significantly smaller than those reported for horseradish peroxidases (HRP) and V‐HPO indicating a higher affinity of the substrates for the V 2 O 5 nanowire surface. Based on the kinetic parameters and similarity with vanadium‐based complexes a mechanism is proposed where an intermediate metastable peroxo complex is formed as the first catalytic step. The nanostructured vanadium‐based material can be re‐used up to 10 times and retains its catalytic activity in a wide range of organic solvents (up to 90%) making it a promising mimic of peroxidase catalysts.
Convenient One‐Pot Preparation of Dimethyl Bicyclo[2.2.2]octane‐1,4‐dicarbolylate, a Key Intermediate for a Novel Adenosine A<sub>1</sub> Receptor Antagonist (2007)

Abstract Dimethyl bicyclo[2.2.2]octane‐1,4‐dicarboxylate (4), a key starting material for a novel adenosine A1 receptor antagonist, was prepared in a one‐pot reaction with convenient workup and improved yield.
The plant vacuolar protein, phytohemagglutinin, is transported to the vacuole of transgenic yeast. (1987)

Phytohemagglutinin (PHA), the major seed lectin of the common bean, Phaseolus vulgaris, accumulates in the parenchyma cells of the cotyledons. It has been previously shown that PHA is cotranslationally inserted into the endoplasmic reticulum with cleavage of the NH2-terminal signal peptide. Two N-linked oligosaccharide side chains are added, one of which is modified to a complex type in the Golgi apparatus. PHA is then deposited in membrane-bound protein storage vacuoles which are biochemically and functionally equivalent to the vacuoles of yeast cells and the lysosomes of animal cells. We wished to determine whether yeast cells would recognize the vacuolar sorting determinant of PHA and target the protein to the yeast vacuole. We have expressed the gene for leukoagglutinating PHA (PHA-L) in yeast under control of the yeast acid phosphatase (PHO5) promoter. Under control of this promoter, PHA-L accumulates to 0.1% of the total yeast protein. PHA-L produced in yeast is glycosylated as expected for a yeast vacuolar glycoprotein. Cell fractionation studies show that PHA-L is efficiently transported to the yeast vacuole. This is the first demonstration that vacuolar targeting information is recognized between two highly divergent species. A small proportion of yeast PHA-L is secreted which may be due to inefficient recognition of the vacuolar sorting signal because of the presence of an uncleaved signal peptide on a subset of the PHA-L polypeptides. This system can now be used to identify the vacuolar sorting determinant of a plant vacuolar protein.