gebhart/patrepeval huggingface dataset:
Half-Sandwich Group 4 Metal Siloxy and Silsesquioxane Complexes:  Soluble Model Systems for Silica-Grafted Olefin Polymerization Catalysts (1999)

The cuboctameric hydroxysilsesquioxane (c-C5H9)7Si8O12(OH) (2), obtained after hydrolysis of (c-C5H9)7Si8O12Cl (1), and triphenylsilanol have been applied as model supports for silica-grafted olefin polymerization catalysts. The ligands were introduced on group 4 metals by either chloride metathesis or protonolysis. Treatment of Cp‘ ‘MCl3 (M = Ti, Zr; Cp‘ ‘ = 1,3-C5H3(SiMe3)2) with silsesquioxane and siloxylithium or -thallium salts, [(c-C5H9)7Si8O13]M‘ (M‘ = Tl (3), Li (4), Li·TMEDA (5)) or Ph3SiOTl gave either the dichloride complexes Cp‘ ‘[(c-C5H9)7Si8O13]MCl2 (M = Ti (6a), Zr (7a)) and Cp‘ ‘[Ph3SiO]TiCl2 (8a) or the monochloride species Cp‘ ‘[(c-C5H9)7Si8O13]2MCl (M = Ti (6b), Zr (7b)) and Cp‘ ‘[Ph3SiO]2MCl (M = Ti (8b), Zr (9)). Similarly, protonolysis of Cp‘ ‘MR3 with the silanols 2 and Ph3SiOH yielded the corresponding silsesquioxane bis(alkyl) complexes Cp‘ ‘[(c-C5H9)7Si8O13]TiR2 (R = CH2Ph (10a), Me (10b)) and triphenylsiloxy bis(alkyl) compounds Cp‘ ‘[Ph3SiO]MR2 (M = Ti, R = CH2Ph (11a), Me (11b); M = Zr, R = CH2Ph (12a)) and the monobenzyl complex Cp‘ ‘[Ph3SiO]2ZrCH2Ph (12b). When activated with MAO, not only the dichloride complexes (6a, 7a, 8a) but also the monochlorides (6b, 7b, 8b, 9) yield active ethylene polymerization catalysts. The observation that even complexes containing a tridentate silsesquioxane ligand, [(c-C5H9)7Si8O12]MCp‘ ‘ (M = Ti (13), Zr (14)), form active ethylene polymerization catalysts when activated with MAO indicates that silsesquioxane and siloxy ligands are easily substituted by MAO. The silsesquioxane and siloxy bis(alkyl) complexes (10, 11, 12a) form active olefin polymerization catalysts when activated with B(C6F5)3, which leaves the M−O bond unaffected. Although the different cone angles of (c-C5H9)7Si8O13 (155°) and Ph3SiO (132°) suggest otherwise, the effective steric congestion around the metal center of (c-C5H9)7Si8O13- and Ph3SiO-stabilized complexes was found to be reasonably comparable. The electronic differences between (c-C5H9)7Si8O12(OH) (2) and Ph3SiOH are more pronounced. pKa measurements and DFT calculations indicate that 2 is notably more Brønsted acidic and electron withdrawing than Ph3SiOH.
DIPHENYLBORYLDIPIVALOYLPHOSPHIDE - THE FIRST EXAMPLE OF BORYLATED 2-PHOSPHA-1, 3-DIONATE (1991)

Abstract C-Trimethylsiloxy substituted phosphaalkene 1 reacts exothermically with diphenylchloroborane. The expected spontaneous 1,3-eIimination of trimethylsiloxydiphenylborane took place to give phosphaalkyne 3 in 1–2% yield only. The symmetrization of intermediately formed C-diphenylboroxysubstituted phosphaalkene 2 into (diphenylboryl)dipivaloylphosphide 4 was found to be the main way of the reaction.
Flow Characteristics and Optimum Dimensions of Spiral-Grooved Thrust Bearings. (1994)

The optimum dimensions of spiral-grooved thrust bearings are determined for both incompressible and compressible fluids, together with the relationships between the optimum dimensions and the steady-state flow characteristics. The Reynolds equation and the modified Reynolds equation are numerically solved by the finite-element method, taking into consideration the wall slip condition. The calculated results reveal that the through-flow rate takes the maximum at the optimum dimensions, and that the optimum spiral angle is larger and the optimum groove depth is smaller in incompressible fluid than in compressible fluid. It is also revealed that the inclination of the bearing plate causes little change in the bearing load capacity in spite of considerable nonaxisymmetricity of pressure distribution.
Clinical Utility of Quantitative Cerebral Blood Flow Measurements during Internal Carotid Artery Test Occlusions (2002)

Quantitative CBF testing, via the intracarotid injection technique, during BTO seems to be an important predictor of stroke after PCO.
Structure and characterization of an enhanced laser-scanning endoscope based on microelectromechanical mirrors (2006)

A miniaturized laser-scanning endoscope is presented that makes use of a composite laser beam for color imaging. A novel approach is followed in the device, which is based on scanning the target tissue with the laser beam using two miniaturized MEMS (microelectromechanical systems) micromirrors and employs specific collection, detection, and postprocessing of the scattered light for reconstructing a color image of the tissue. A resolution of the order of 16 line pairs/mm is achieved for a working distance of 50 mm while the focal depth is larger than 5 mm. Key considerations of the system design are presented, along with results on the operation of the micromirrors, an analysis of the optical design of the endoscope head, and remarks on the assessment of image quality.
Nonbulk convergence of solvent spectral shifts in doped molecular clusters (1991)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNonbulk convergence of solvent spectral shifts in doped molecular clustersXiuling Li, M. Y. Hahn, M. S. El-Shall, and Robert L. WhettenCite this: J. Phys. Chem. 1991, 95, 22, 8524–8528Publication Date (Print):October 1, 1991Publication History Published online1 May 2002Published inissue 1 October 1991https://pubs.acs.org/doi/10.1021/j100175a022https://doi.org/10.1021/j100175a022research-articleACS PublicationsRequest reuse permissionsArticle Views48Altmetric-Citations24LEARN 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 options Get e-Alerts
Activity of CAR19 T cells secreting impact fusion proteins against hematopoietic and solid tumors. (2018)

e15046 Background: CAR T cells targeting CD19 (CAR19s) can eradicate B cell leukemias and lymphomas. We have engineered CAR19s to secrete a wide variety of retargeting fusion proteins (FP) by encoding expression cassettes downstream of the CAR sequence in lentiviral vectors. The FP consist of the CD19 extracellular domain linked to one or more scFvs. The FP redirect CAR19 T cell cytotoxic activity to any tumor antigen of interest by coating that antigen with CD19 via the scFv. Further, multiple antigens can be coated with CD19 by using bi-specific FP (bi-FP) formats. Therefore, CAR19s serve as a platform to target diverse antigens. Methods: A lentiviral vector with an MSCV promoter was used to express a CAR19 construct and FP. The FP and bi-FP were designed to encode the extracellular domain of the CD19 protein, followed by one or two scFv sequences, separated from the CAR sequence by a P2A cleavage site, a design termed IMPACT (Integrated Modular Proteins for Adoptive Cell Therapy). Results: The CD19/anti-Her2 FP was highly potent in cytotoxicity assays targeting Her2+/CD19- solid tumor cell lines. The concentration of fusion protein required to reduce tumor cell number by 50% was 10 pM (0.7 ng/ml). Primary donor T cells transduced with the IMPACT vector encoding the CAR19 domain and the CD19/anti-Her2 FP secreted > 20 ng/ml of FP in cell culture. Cytotoxic activity of this redirected CAR19 against Her2+ SKOV3 tumor cells was demonstrated in vitro and in vivo. Normal B cells promoted persistence. A CAR19-CD19/anti-CD20 FP specifically killed malignant B cells expressing CD19, CD19 and CD20, or CD20 alone. A bi-specific FP containing CD19 linked to anti-Her2 and anti-EGFR scFv had specific activity against both antigens with a potency of 0.75 pM. In each example, the potent cytotoxicity was specifically mediated by the secreted fusion protein. Conclusions: The IMPACT platform addresses critical issues in cell therapy including CAR persistence, antigen escape and antigen heterogeneity, and provides important solutions for treating both hematologic and solid tumors. The potency of redirected cytotoxicity supports clinical development of CAR19/IMPACT programs.
Octave-spanning coherent supercontinuum generation in silicon on insulator from 1.06 μm to beyond 2.4 μm (2017)

Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong demand. Due to two-photon absorption in silicon, however, much nonlinear research is shifting towards unconventional photonics platforms. In this work, we demonstrate the generation of an octave-spanning coherent supercontinuum in a silicon waveguide covering the spectral region from the near- to shortwave-infrared. With input pulses of 18 pJ in energy, the generated signal spans the wavelength range from the edge of the silicon transmission window, approximately 1.06 to beyond 2.4 μm, with a -20 dB bandwidth covering 1.124-2.4 μm. An octave-spanning supercontinuum was also observed at the energy levels as low as 4 pJ (-35 dB bandwidth). We also measured the coherence over an octave, obtaining , in good agreement with the simulations. In addition, we demonstrate optimization of the third-order dispersion of the waveguide to strengthen the dispersive wave and discuss the advantage of having a soliton at the long wavelength edge of an octave-spanning signal for nonlinear applications. This research paves the way for applications, such as chip-scale precision spectroscopy, optical coherence tomography, optical frequency metrology, frequency synthesis and wide-band wavelength division multiplexing in the telecom window.
Automatic Evaluation of Children Reading Aloud on Sentences and Pseudowords (2017)

Reading aloud performance in children is typically assessed by teachers on an individual basis, manually marking reading time and incorrectly read words. A computational tool that assists with recording reading tasks, automatically analyzing them and providing performance metrics could be a significant help. Towards that goal, this work presents an approach to automatically predicting the overall reading aloud ability of primary school children (6-10 years old), based on the reading of sentences and pseudowords. The opinions of primary school teachers were gathered as ground truth of performance, who provided 0-5 scores closely related to the expectations at the end of each grade. To predict these scores automatically, features based on reading speed and number of disfluencies were extracted, after an automatic disfluency detection. Various regression models were trained, with Gaussian process regression giving best results for automatic features. Feature selection from both sentence and pseudoword reading tasks gave the closest predictions, with a correlation of 0.944. Compared to the use of manual annotation with the best correlation being 0.952, automatic annotation was only 0.8% worse. Furthermore, the error rate of predicted scores relative to ground truth was found to be smaller than the deviation of evaluators’ opinion per child.
Electrical resistance of the current collector controls lithium morphology (2022)

The electrodeposition of low surface area lithium is critical to successful adoption of lithium metal batteries. Here, we discover the dependence of lithium metal morphology on electrical resistance of substrates, enabling us to design an alternative strategy for controlling lithium morphology and improving electrochemical performance. By modifying the current collector with atomic layer deposited conductive (ZnO, SnO<sub>2</sub>) and resistive (Al<sub>2</sub>O<sub>3</sub>) nanofilms, we show that conductive films promote the formation of high surface area lithium deposits, whereas highly resistive films promote the formation of lithium clusters of low surface area. We reveal an electrodeposition mechanism in which radial diffusion of electroactive species is promoted on resistive substrates, resulting in lateral growth of large (150 µm in diameter) planar lithium deposits. Using resistive substrates, similar lithium morphologies are formed in three distinct classes of electrolytes, resulting in up to ten-fold improvement in battery performance. Ultimately, we report anode-free pouch cells using the Al<sub>2</sub>O<sub>3</sub>-modified copper that maintain 60 % of their initial discharge capacity after 100 cycles, displaying the benefits of resistive substrates for controlling lithium electrodeposition.
Negative-pressure-induced helimagnetism in ferromagnetic cubic perovskites Sr1−xBaxCoO3 (2018)

Helimagnetic materials are identified as promising for novel spintronic applications. Since helical spin order is manifested as a compromise of competing magnetic exchange interactions, its emergence is limited by unique constraints imposed by the crystalline lattice and the interaction geometries as exemplified by the multiferroic perovskite manganites with large orthorhombic distortion. Here we show that a simple cubic perovskite ${\mathrm{SrCoO}}_{3}$ with room-temperature ferromagnetism has the potential to host helimagnetic order upon isotropic lattice expansion. Increasing the Ba content $x$ in ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Ba}}_{x}{\mathrm{CoO}}_{3}$ continuously expands the cubic lattice, eventually suppressing the ferromagnetic order near $x=0.4$ where helimagnetic correlations are observed as incommensurate diffuse magnetic scattering by neutron-diffraction measurements. The emergence of helimagnetism is semiquantitatively reproduced by first-principles calculations, leading to the conjecture that a simple cubic lattice with strong $d\text{\ensuremath{-}}p$ hybridization can exhibit a variety of novel magnetic phases originating from competing exchange interactions.
Sonochemical synthesis of tungsten sulfide nanorodsElectronic supplementary information (ESI) available: TGA curve for the as-prepared product; AFM image of WS2 packs of nanorods. See http://www.rsc.org/suppdata/jm/b1/b110867k/ (2002)

Amorphous WS2 has been prepared by ultrasound irradiation of W(CO)6 solution in diphenylmethane (DPhM) in the presence of a slight excess of sulfur at 90 °C under argon. Heating the amorphous powder at 800 °C under argon yields WS2 nanorods and their packings. The average size of WS2 nanorods was found to be 3–10 nm and 1–5 µm in thickness and length, respectively. The prepared WS2 has been characterized by elemental analysis, X-ray powder diffraction measurements, FTIR spectroscopy, differential scanning calorimetry, thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, atomic force microscopy and energy dispersive X-ray analysis.
High Frequency Dynamic Nuclear Polarization (2013)

During the three decades 1980–2010, magic angle spinning (MAS) NMR developed into the method of choice to examine many chemical, physical, and biological problems. In particular, a variety of dipolar recoupling methods to measure distances and torsion angles can now constrain molecular structures to high resolution. However, applications are often limited by the low sensitivity of the experiments, due in large part to the necessity of observing spectra of low-γ nuclei such as the I = [1 over 2] species [superscript 13]C or [superscript 15]N. The difficulty is still greater when quadrupolar nuclei, such as [superscript 17]O or [superscript 27]Al, are involved. This problem has stimulated efforts to increase the sensitivity of MAS experiments. A particularly powerful approach is dynamic nuclear polarization (DNP) which takes advantage of the higher equilibrium polarization of electrons (which conventionally manifests in the great sensitivity advantage of EPR over NMR). In DNP, the sample is doped with a stable paramagnetic polarizing agent and irradiated with microwaves to transfer the high polarization in the electron spin reservoir to the nuclei of interest. The idea was first explored by Overhauser and Slichter in 1953. However, these experiments were carried out on static samples, at magnetic fields that are low by current standards. To be implemented in contemporary MAS NMR experiments, DNP requires microwave sources operating in the subterahertz regime, roughly 150–660 GHz, and cryogenic MAS probes. In addition, improvements were required in the polarizing agents, because the high concentrations of conventional radicals that are required to produce significant enhancements compromise spectral resolution. In the last two decades, scientific and technical advances have addressed these problems and brought DNP to the point where it is achieving wide applicability. These advances include the development of high frequency gyrotron microwave sources operating in the subterahertz frequency range. In addition, low temperature MAS probes were developed that permit in situ microwave irradiation of the samples. And, finally, biradical polarizing agents were developed that increased the efficiency of DNP experiments by factors of ~4 at considerably lower paramagnet concentrations. Collectively, these developments have made it possible to apply DNP on a routine basis to a number of different scientific endeavors, most prominently in the biological and material sciences. This Account reviews these developments, including the primary mechanisms used to transfer polarization in high frequency DNP, and the current choice of microwave sources and biradical polarizing agents. In addition, we illustrate the utility of the technique with a description of applications to membrane and amyloid proteins that emphasizes the unique structural information that is available in these two cases.
Vinylogous Dehydration by a Polyketide Dehydratase Domain in Curacin Biosynthesis (2016)

Polyketide synthase (PKS) enzymes continue to hold great promise as synthetic biology platforms for the production of novel therapeutic agents, biofuels, and commodity chemicals. Dehydratase (DH) catalytic domains play an important role during polyketide biosynthesis through the dehydration of the nascent polyketide intermediate to provide olefins. Our understanding of the detailed mechanistic and structural underpinning of DH domains that control substrate specificity and selectivity remains limited, thus hindering our efforts to rationally re-engineer PKSs. The curacin pathway houses a rare plurality of possible double bond permutations containing conjugated olefins as well as both cis- and trans-olefins, providing an unrivaled model system for polyketide dehydration. All four DH domains implicated in curacin biosynthesis were characterized in vitro using synthetic substrates, and activity was measured by LC-MS/MS analysis. These studies resulted in complete kinetic characterization of the all-trans-trienoate-forming CurK-DH, whose k<sub>cat</sub> of 72 s<sup>-1</sup> is more than 3 orders of magnitude greater than that of any previously reported PKS DH domain. A novel stereospecific mechanism for diene formation involving a vinylogous enolate intermediate is proposed for the CurJ and CurH DHs on the basis of incubation studies with truncated substrates. A synthetic substrate was co-crystallized with a catalytically inactive Phe substitution in the His-Asp catalytic dyad of CurJ-DH to elucidate substrate-enzyme interactions. The resulting complex suggested the structural basis for dienoate formation and provided the first glimpse into the enzyme-substrate interactions essential for the formation of olefins in polyketide natural products. This examination of both canonical and non-canonical dehydration mechanisms reveals hidden catalytic activity inherent in some DH domains that may be leveraged for future applications in synthetic biology.
Activity-Dependent Regulation of Surface Glucose Transporter-3 (2011)

Glucose transporter 3 (GLUT3) is the main facilitative glucose transporter in neurons. Glucose provides neurons with a critical energy source for neuronal activity. However, the mechanism by which neuronal activity controls glucose influx via GLUT3 is unknown. We investigated the influence of synaptic stimulation on GLUT3 surface expression and glucose import in primary cultured cortical and hippocampal neurons. Synaptic activity increased surface expression of GLUT3 leading to an elevation of intracellular glucose. The effect was blocked by NMDA receptor (NMDAR) and neuronal nitric oxide synthase (nNOS) inhibition. The Akt inhibitor I (Akt-I) blocked NMDAR-induced GLUT3 surface expression while a nNOS-phosphomimetic mutant (S1412D) enhanced GLUT3 expression at cell surface. These results suggest that NMDAR/Akt-dependent nNOS phosphorylation is coupled to GLUT3 trafficking. We demonstrated that activation of cGMP-dependent protein kinase (cGK) increased the surface expression of GLUT3, which was repressed by Rp-8-pCPT-cGMPS, a potent cell-permeable inhibitor of cGKs. These studies characterize the molecular basis for activity-dependent increases in surface GLUT3 after stimulation of the NMDARs. NMDAR-induced increase in surface GLUT3 represents a novel pathway for control of energy supply during neuronal activity that is critical for maintaining glucose homeostasis during neuronal transmission.
METHANOLIC EXTRACTION OF FREE FERULIC ACID FROM OIL PALM (2020)

Ferulic acid, a hydroxycinnamic acid, is known to exhibit anti-microbial, anti-inflammatory and antioxidant properties, making it a valuable compound for various applications. Study was conducted to investigate the extraction of free ferulic acid (ferulic acid that is not linked to lignin or other biopolymers) in the oil palm fruits, pressed fibre, empty fruit bunches (EFB), as well as its leaves, termed as frond. The extraction of free ferulic acid from these palm components was carried out using an alcoholic solution at various sample to solvent ratios. With the exception of fresh sterilised fruits, varying the sample to solvent ratio did not seem to have significant effect on the amount of ferulic acid extracted. Similarly, except for EFB and sterilised fruits, the amount of ferulic acid extracted was not affected by the conditions of the samples (fresh or dried) prior to extraction. The free ferulic acid content in oil palm fruits, pressed fibre, EFB and oil palm frond ranged from 230-670 mg kg -1 .
21st Century Locomotive Technology: Quarterly Technical Status Report 11 DOE/AL68284-TSR11 (2006)

The fuel injection hardware on the single cylinder research engine was upgraded and performance trends were quantified. The effects of fuel injection rate shapes were studied. Long-term cycling of subscale battery cell assemblies has identified aging trends. Follow-up vibration testing of an instrumented COTS battery was performed. Optimal trip planning algorithms were implemented and demonstrated in the interactive, real-time simulation environment.