gebhart/patrepeval huggingface dataset:
Organoactinide-Mediated Hydrothiolation of Terminal Alkynes with Aliphatic, Aromatic, and Benzylic Thiols (2009)

Atom-efficient organoactinide-catalyzed intermolecular hydrothiolation of terminal alkynes is achieved by Th(IV) and U(IV) complexes to yield vinyl sulfides. The conversion is highly Markovnikov selective and is capable of utilizing aromatic, benzylic, and aliphatic thiols. Kinetic measurements of the transformation mediated by Me2SiCp2′′Th[CH2(TMS)]2 (1a; Cp′′ = η5-Me4C5) shows the reaction is zero-order in [thiol], first-order in [1a], first-order in [alkyne] at lower alkyne concentrations, and zero-order at higher [alkyne]. The proposed catalytic cycle invokes turnover-limiting insertion of the alkyne into the Th−S bond followed by a rapid Th−C bond protonolysis. All reactions except entries 7 and 8 are quantitative by 1H NMR.
Review of Improvements on Shell-and-Tube Heat Exchangers With Helical Baffles (2010)

Helical baffles are employed increasingly in shell-and-tube heat exchangers (helixchangers) for their significant advantages in reducing pressure drop, vibration, and fouling while maintaining a higher heat transfer performance. In order to make good use of helical baffles, serial improvements have been made by many researchers. In this paper, a general review is provided of developments and improvements on helixchangers, which includes the discontinuous helical baffles, continuous or combined helical baffles, and the combined multiple shell-pass helixchangers. Extensive results from experiments and numerical simulations indicate that these helixchangers have better flow and heat transfer performance than the conventional segmental baffled heat exchangers. Based on these new improvements, the conventional heat exchangers with segmental baffles might be replaced by helixchangers in industrial applications to save energy, reduce cost, and prolong the service life and operation time.
Oxygen Saturation of the Low Osmolar Contrast Media Iohexol, Ioxaglate and Iodixanol (1990)

During coronary angiography the exchange of blood with a contrast medium solution causes a period of hypoxia. To investigate whether oxygen saturation of the contrast medium could be beneficial, low osmolar contrast media were infused without and with oxygen saturation into the coronary arteries of the isolated rabbit heart. Iohexol (150–300 mg I/ml, without NaCl or with 20–30 mM NaCl), iodixanol (320 mg I/ml, contains 24 mM NaCl) and ioxaglate (160 mg I/ml, contains 75 mM Na+) were infused without and with oxygen saturation. The decrease in contractile force (CF) of the heart, from the contrast medium solutions, was reduced when the solutions were saturated with oxygen. Oxygen saturation of iohexol (350 mg I/ml, without or with 10 mM NaCl) did not change the frequency of ventricular fibrillations (VF). Low osmolar contrast media, when saturated with oxygen, thus caused a reduced decrease in CF without changing the frequency of VF. This might be beneficial in clinical cardioangiography by reducing the adv...
Self-pulsation in multisection laser diodes with a DFB reflector (2006)

A novel self-pulsation regime is observed in multisection laser diodes which consist of a loss-coupled distributed-feedback (DFB) section, a phase control section, and gain sections, where 10-GHz self-pulsation due to compound cavity mode beating has been reported with the DFB section operated as a single-mode laser. When the DFB section is below threshold current, the devices give the self-pulsation in a very wide operating range. We attribute the pulsation to passive mode-locking and also confirm that this structure is applicable to 40-GHz operation.
Structure–Redox–Relaxivity Relationships for Redox Responsive Manganese-Based Magnetic Resonance Imaging Probes (2014)

A library of 10 Mn-containing complexes capable of switching reversibly between the Mn(II) and Mn(III) oxidation states was prepared and evaluated for potential usage as MRI reporters of tissue redox activity. We synthesized N-(2-hydroxybenzyl)-N,N',N'-ethylenediaminetriacetic acid (HBET) and N-(2-hydroxybenzyl-N,N',N'-trans-1,2-cyclohexylenediaminetriacetic acid (CyHBET) ligands functionalized (-H, -OMe, -NO2) at the 5-position of the aromatic ring. The Mn(II) complexes of all ligands and the Mn(III) complexes of the 5-H and 5-NO2 functionalized ligands were synthesized and isolated, but the Mn(III) complexes with the 5-OMe functionalized ligands were unstable. (1)H relaxivity of the 10 isolable complexes was measured at pH 7.4 and 37 °C, 1.4 T. Thermodynamic stability, pH-dependent complex speciation, hydration state, water exchange kinetics of the Mn(II) complexes, and pseudo-first order reduction kinetics of the Mn(III) complexes were studied using a combination of pH-potentiometry, UV-vis spectroscopy, and (1)H and (17)O NMR measurements. The effects of ligand structural and electronic modifications on the Mn(II/III) redox couple were studied by cyclic voltammetry. The Mn(II) complexes are potent relaxation agents as compared to the corresponding Mn(III) species with [Mn(II)(CyHBET)(H2O)](2-) exhibiting a 7.5-fold higher relaxivity (3.3 mM(-1) s(-1)) than the oxidized form (0.4 mM(-1) s(-1)). At pH 7.4, Mn(II) exists as a mixture of fully deprotonated (ML) and monoprotonated (HML) complexes and Mn(II) complex stability decreases as the ligands become more electron-releasing (pMn for 10 μM [Mn(II)(CyHBET-R')(H2O)](2-) decreases from 7.6 to 6.2 as R' goes from -NO2 to -OMe, respectively). HML speciation increases as the electron-releasing nature of the phenolato-O donor increases. The presence of a water coligand is maintained upon conversion from HML to ML, but the water exchange rate of ML is faster by up to 2 orders of magnitude (k(ex)(310) for H[Mn(II)(CyHBET)(H2O)](-) and [Mn(II)(CyHBET)(H2O)](2-) are 1.2 × 10(8) and 1.0 × 10(10) s(-1), respectively). The Mn(II/III) redox potential can be tuned over a range of 0.30 V (E(1/2) = 0.27-0.57 V) through electronic modifications to the 5-substituent of the aromatic ligand component. However, care must be taken in tuning the ligand electronics to avoid Mn(III)-ligand autoredox. Taken together, these results serve to establish criteria for optimizing Mn(III) versus Mn(II) relaxivity differentials, complex stability, and Mn(II/III) redox potential.
Comparison of acoustic reflectance measurement techniques (1997)

Acoustic reflectance measurement techniques have been investigated that are calibrated using pressure responses measured in one or more cylindrical tubes and viscothermal models of wall loss. Of clinical interest as a test of hearing is a single-microphone technique to measure the inherently nonlinear ear-canal reflectance at various stimulus levels. Calibration of the probe containing the sound source/receiver consists of measuring the source reflectance of the probe and the incident pressure response at each stimulus level. A single-tube technique relies on separability of the tube response into incident and reflected signals, while multi-tube techniques rely on solving an overdetermined matrix equation of responses. The matrix includes weighting factors that differ across tubes by reflectance or SPL to control for inadequate signal-to-noise ratios at isolated frequencies, and a regularized matrix inverse solution is compared to the pseudoinverse solution. The single-tube technique functions as well as the best performing multi-tube technique, and requires fewer calibration steps. However, there is an ambiguity between the tube length chosen in the tube response model and the measured phase of the source reflectance. This ambiguity is addressed by a priori knowledge of the phase response of the probe averaged across frequency.
A new MOS-gated power thyristor structure with turn-off achieved by controlling the base resistance (1991)

A new MOS-gated power thyristor structure, called the base-resistance-controlled thyristor (BRT), is described. In this structure, the turn-off of a thyristor with an N-drift region is achieved by reducing the resistance of the P-base region under MOS-gate control. In contrast with previous devices, a P-channel MOSFET integrated in the N-drift region is used for this purpose. It has been shown, by two-dimensional numerical simulations and experimental measurements on devices fabricated using a seven-mask process, that devices with 600-V forward blocking capabilities can be achieved with a forward drop close to that for a thyristor. The ability to turn off the thyristor current flow has been verified over a broad range of current densities.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Magnetic Shielding of the Acceleration Channel Walls in a Long-Life Hall Thruster (2010)

In a Qualification Life Test (QLT) of the BPT-4000 Hall thruster that recently accumulated >10,000 h it was found that the erosion of the acceleration channel practically stopped after ~5,600 h. Numerical simulations of this thruster using a 2-D axisymmetric, field-aligned-mesh (MFAM) plasma solver reveal that the process that led to this significant reduction of the erosion was multifaceted. It is found that when the channel receded from its early-in-life geometry to its steady-state configuration several changes in the near-wall plasma and sheath were induced by the field that, collectively, constituted an effective shielding of the walls from any significant ion bombardment. Because all such changes in the behavior of the ionized gas near the eroding surfaces were caused by the topology of the field there, we term this process magnetic shielding.
Lubricant film thickness mapping using a capacitance technique on magnetic thin-film rigid disks (1998)

We describe a novel capacitance measurement technique which is used to determine lubricant film thickness on magnetic thin-film rigid disks. Using this technique, variations in lubricant thickness as small as 0.1 nm can be measured quickly and nondestructively. Film thickness measurements made with an ellipsometer are found to be comparable to the capacitance measurements. We compare the uniformity in film thickness of disks lubricated with a dip-coating process with that of disks lubricated with a drain-coating process and find that the drain coated disks have better film uniformity than those that are dip coated. Also, wear tracks in fully bonded and partially bonded perfluoropolyether lubricants are profiled. We find that lubricant depletion occurs more rapidly in fully bonded lubricant than in partially bonded lubricant and that some recovery of the partially bonded lubricant occurs while none is observed in fully bonded lubricant.
A Novel Form of Dipeptidylpeptidase IV Found in Human Serum. (1995)

Human CD26, a Type II membrane glycoprotein with intrinsic dipeptidylpeptidase IV (DPPIV) activity and ability to bind adenosine deaminase type I (ADA-1), is expressed on epithelial cells constitutively, but on T lymphocytes its expression is regulated. A soluble form of CD26/DPPIV has been described in plasma and related to immunological status, but it has been defined by the presence of DPPIV activity rather than by isolation. Using nondenaturing chromatographic techniques followed by nondenaturing native preparative electrophoresis, we obtained a homogeneous preparation of soluble serum DPPIV and compared it with a recombinant soluble CD26/DPPIV (rsCD26). We show that serum DPPIV is a monomer of 175 kDa in contrast to rsCD26 of 105-110 kDa, that it exists as a trimer, and that it is probably a serine proteinase. Deglycosylation removed N-linked sugar from both serum DPPIV and rsCD26; no O-linked glycosylation was observed, revealing a protein core of 130 kDa for serum DPPIV. The large serum form expresses functional DPPIV activity with substrate and inhibitor specificities and pH activity profile similar to those of rsCD26. Epitope analysis showed that monoclonal antibodies against five epitopes expressed by rsCD26 also bound, but more weakly, with serum DPPIV. Analysis of peptides after limiting proteolysis and N-terminal sequences reveals no homology with rsCD26 but some identity with other peptidases. Unlike rsCD26, the serum form does not bind ADA-1 and has no ADA-1 already associated with it. Similarly to rsCD26, serum DPPIV is a potent T cell costimulator. We conclude that the serum form of DPPIV is unique and is not a breakdown product of membrane CD26. The conservation of DPPIV activity and five epitopes specific to rsCD26 suggest, however, a significant structural similarity.
Enhanced topical delivery of tacrolimus by a carbomer hydrogel formulation with transcutol P (2016)

Tacrolimus (TAC), a non-steroidal anti-inflammatory and immunosuppressive agent, is used for the treatment of atopic dermatitis (AD) and skin immune diseases. TAC-loaded topical hydrogel formulations composed of carbomer, carnosine, transcutol P (diethylene glycol monoethyl ether) and humectant were prepared. For comparison, TAC-loaded topical cream-type formulations were also prepared and commercially available TAC ointment was used as a reference. A drug release study in vitro revealed that the total amount of TAC released from hydrogels over 24 h was approximately 30 times greater than that for the reference formulation. Compared to the reference ointment and creams, carbomer gel formulations showed higher skin permeation and retention of TAC (significantly different at p < 0.05), especially those with more than 10% of transcutol P. Therefore, carbomer gel formulations with sufficient levels of transcutol P are good candidates for skin delivery of TAC and have potential as therapeutic agents for the treatment of AD or immune skin disorders.
Impact Microactuator Driven by Electrostatic Force (2002)

A novel micromachined actuator which is developed to produce precise and unlimited displacement. The actuator is driven by impact force between a silicon micro-mass and a stopper. A suspended silicon mass is encapsulated between glass plates and driven by electrostatic force. By hitting a stopper, it generates impact force to drive the whole actuator in a small step (∿10nm). It is a micromachined and electrostatic version of the impact-drive actuator. The overall dimension of the device is 3mm×3mm. The driving voltage is 100V and average speed is 2.7μm/s. The total thickness is 600μm.
Abstract 3009: Identification of cancer specific ERG target gene signatures. (2013)

Abstract Introduction and Objective: ETS Related Gene (ERG) is aberrantly expressed in more than two-third of prostate cancers (CaP) due to gene fusions. CaP specific TMPRSS2- ERG fusion is a promising biomarker and potential therapeutic target. Cancer associated expression of ERG have also been described in several cancers. However, the precise molecular mechanisms underlying ERG induced oncogenic process in specific cancers are not clearly understood. Identification and thorough characterization of downstream target genes may aid to design effective therapeutic strategies for ERG expressing cancers. In this study, we have identified cancer specific ERG target gene signature of ERG expressing cancer cells that may be utilized as therapeutic targets for the treatment of ERG expressing CaP patients. Methods: Illumina BeadChips microarray analysis was performed to profile ERG specific RNA signature from ERG positive tumor cell lines and normal ERG expressing endothelial cells transfected with either ERG specific siRNA or non-targeting siRNA. Functional gene clustering and Venn diagram analysis was employed to show the overlap of the common and unique gene sets regulated by ERG in these cells. Gene expression was analyzed by Western blot, QRT-PCR, and immunofluorescence assays. Results: Biological function based gene clustering analysis identified two distinct gene signatures (normal and cancer specific) regulated by ERG. Knockdown of ERG in malignant cells resulted in overexpression of differentiation markers such as MSMB, KLK3, SLC45A3, NKX3.1, and NOV4 in prostate cancer (VCaP cells), and APC, DCC, CTNNB1, and NKD1 in colon cancer (COLO320 cells). In contrast, knockdown of ERG in normal endothelial-derived HUVEC cells resulted in the repression of differentiation markers such as CDH5, ANGEL2, and TIE1. Conclusions: We identified tumor specific ERG target gene signature using normal and various cancer cell lines. This study confirmed the cell context dependent role of ERG in tumor and in normal endothelial cells. These observations have the potential to enhance our understanding of ERG biological functions thereby facilitate the design of suitable therapeutic mechanism. Citation Format: Ahmed Mohamed, Lakshmi Ravindranth, Shilpa Katta, Shyh-Han Tan, Yongmei Chen, Gyorgy Petrovics, Albert Dobi, Shiv Srivastava. Identification of cancer specific ERG target gene signatures. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3009. doi:10.1158/1538-7445.AM2013-3009
Novel Large-Hydrophobe Alkoxy Carboxylate Surfactants for Enhanced Oil Recovery (2012)

Abstract A new class of surfactants has been developed and tested for chemical enhanced oil recovery that shows excellent performance under harsh reservoir conditions. These novel Guerbet alkoxy carboxylate surfactants fulfill this need by providing large, branched hydrophobes, flexibility in the number of alkoxylate groups, and stability in both alkaline and non- alkaline environments at temperatures up to at least 120 °C. The new carboxylate surfactants perform better than previously available commercial surfactants, they can be used under harsh reservoir conditions, and they can be manufactured at a lower cost from widely available feedstocks. A formulation containing the combination of a carboxylate surfactant and a sulfonate co-surfactant resulted in a synergistic interaction that has the potential to further reduce the total chemical cost. Both ultra- low interfacial tension with the oils and a clear aqueous solution even under harsh conditions such as high salinity, high hardness and high temperature with or without alkali can be obtained using these new large-hydrophobe alkoxy carboxylate surfactants. Both sandstone and carbonate corefloods were conducted with excellent results. Formulations have been developed for both active oils (contains naturally occurring carboxylic acids) and inactive oils (oils that do not produce soap/carboxylic acid) with excellent results. The new class of surfactants is a major breakthrough that greatly increases the commercial potential of chemical enhanced oil recovery.
Computational coherent averaging for free-running dual-comb spectroscopy (2019)

Dual-comb spectroscopy is a rapidly developing spectroscopic technique that does not require any opto-mechanical moving parts and enables broadband and high-resolution measurements with microsecond time resolution. However, for high sensitivity measurements and extended averaging times, high mutual coherence of the comb-sources is essential. To date, most dual-comb systems employ coherent averaging schemes that require additional electro-optical components, which increase system complexity and cost. More recently, computational phase correction approaches that enables coherent averaging of spectra generated by free-running systems have gained increasing interest. Here, we propose such an all-computational solution that is compatible with real-time data acquisition architectures for free-running systems. The efficacy of our coherent averaging algorithm is demonstrated using dual-comb spectrometers based on quantum cascade lasers, interband cascade lasers, mode-locked lasers, and optically-pumped microresonators.
Stabilization of the bioactivity of tumor necrosis factor by its soluble receptors. (1992)

The receptors for tumor necrosis factor (TNF) exist in cell-associated as well as soluble forms, both binding specifically to TNF. Since the soluble forms of TNF receptors (sTNF-Rs) can compete with the cell-associated TNF receptors for TNF, it was suggested that they function as inhibitors of TNF activity; at high concentrations, the sTNF-Rs indeed inhibit TNF effects. However, we report here that in the presence of low concentrations of the sTNF-Rs, effects of TNF whose induction depend on prolonged treatment with this cytokine are augmented, reflecting an attenuation by the sTNF-Rs of spontaneous TNF activity decay. Evidence that this stabilization of TNF activity by the sTNF-Rs follows from stabilization of TNF structure within the complexes that TNF forms with the sTNF-Rs is presented here, suggesting that the sTNF-Rs can affect TNF activity not only by interfering with its binding to cells but also by stabilizing its structure and preserving its activity, thus augmenting some of its effects.
DragonNet: A Robust Mobile Internet Service System for Long Distance Trains (2012)

Wide range wireless networks often suffer from annoying service deterioration due to ever-changing wireless environments. This is especially the case with passengers on long-distance trains (LDT, such as intercity, interprovincial, and international commuter trains) connecting to the Internet. To improve the service quality of wide-area wireless networks, we present the DragonNet system and protocol with practical implementations. The DragonNet system is a chained gateway that consists of a group of interlinked DragonNet routers running the DragonNet protocol for node failure amortization across the long stretching router chain. The protocol makes use of the spatial diversity of wireless signals when not all spots on a surface see the same level of radio frequency radiation. In the case of an LDT of around 500 meters, it is highly possible that some of the DragonNet routers in the gateway chain still see sound signal quality when the LDT is partially blocked from the wireless Internet. The DragonNet protocol fully utilizes this feature to amortize single-point router failure over the whole router chain by intelligently rerouting traffic on failed ones to sound ones. We have implemented the DragonNet system and tested it in real railways over a period of three months. Our results have pinpointed two fundamental contributions of the DragonNet protocol. First, DragonNet significantly reduces the average temporary communication blackout (i.e., no Internet connection) to 1.5 seconds compared with 6 seconds without the DragonNet protocol. Second, DragonNet nearly doubles the aggregate system throughput compared with gateway without running the DragonNet protocol.