gebhart/patrepeval huggingface dataset:
Studies in isoxazole chemistry. 11.' Issxazoles from the A2-isoxazolin-5-01s and their acetates (1970)

Various 3-substituted-5-acetoxy-A'-isoxazolines were made by the 1,3-dipolar cycloaddition of nitrile oxides to vinyl acetate or isopropenyl acetate. These compounds were readily converted in high yield to 3-substituted isoxazoles or 3-substituted-5-methylisoxazoles respectively, on heating. Treatment of the 3-substituted-5-acetoxy-A2-isoxazolines with sodium hydroxide in methanol gave rise to the stable A2-isoxazolin-5-01s after acidification. These compounds could also be converted to 3-substituted isoxazoles by heating alone, or better, in the presence of thionyl chloride. The nuclear magnetic resonance spectra of these compounds are discussed. Canadian Journal of Chemistry, 48, 467 (1970) In a continuation of our work on isoxazoles, we had occasion to require various 3-substituted isoxazoles. It is reported that 3-substituted isoxazoles can be made by the action of hydroxylamine on P-ketoaldehydes (I, 2) or P-chlorovinylketones(3). In the last two instances, the preparation is complicated by the fact that a mixture of the 3- and 5-substituted isoxazoles usually results. It appeared to us, that a much more convenient, unambiguous synthesis, suitable for the preparation of relatively large amounts of various 3-substituted isoxazoles was via the relatively neglected A2-isoxazolines. The isoxazolines are readily obtained by the 1,3-dipolar cycloaddition of nitrile oxides to olefins (4, 5). It has been noted (6, 7, 8) that isoxazolines of structure 1, with R = Cl or NO,, readily eliminate HR to give isoxazoles 3; and a similar elimination occurs with isoxazolines of structure 2, when R = C1, Br, alkoxy, or amine (9-14). This area has not been utilized sufficiently for the specific purpose of preparing isoxazoles. It has been shown that other groups can also be eliminated in this manner from A2-isoxazolines to give rise to the more stable aromatic isoxazole ring. Thus Quilico and Speroni (15) found that benzonitrile oxide reacted with P-diketones, only in presence of base, forming isoxazoles 5. They suggested that the reaction involved a 1,3-dipolar cycloaddition of the nitrile oxide to the en01 form of the P-diketone, with subsequent dehydration of the resulting A2-isoxazolin-5-01 4, which could not be isolated. D'Alcontres and Griinanger (16) obtained 3-phenylisoxazole by heating 3-phenyl-5-acetoxyA2-isoxazoline for several hours with methanolic hydrogen chloride and assumed that it was formed by dehydration of the intermediate alcohol (which was not isolated). Various isoxazoles have been obtained in a similar manner
Seamless lateral graphene p–n junctions formed by selective in situ doping for high-performance photodetectors (2018)

Lateral graphene p-n junctions are important since they constitute the core components in a variety of electronic/photonic systems. However, formation of lateral graphene p-n junctions with a controllable doping levels is still a great challenge due to the monolayer feature of graphene. Herein, by performing selective ion implantation and in situ growth by dynamic chemical vapor deposition, direct formation of seamless lateral graphene p-n junctions with spatial control and tunable doping is demonstrated. Uniform lattice substitution with heteroatoms is achieved in both the boron-doped and nitrogen-doped regions and photoelectrical assessment reveals that the seamless lateral p-n junctions exhibit a distinct photocurrent response under ambient conditions. As ion implantation is a standard technique in microelectronics, our study suggests a simple and effective strategy for mass production of graphene p-n junctions with batch capability and spatial controllability, which can be readily integrated into the production of graphene-based electronics and photonics.
Novel protein-tyrosine kinase gene (hck) preferentially expressed in cells of hematopoietic origin. (1987)

Protein-tyrosine kinases are implicated in the control of cell growth by virtue of their frequent appearance as products of retroviral oncogenes and as components of growth factor receptors. Here we report the characterization of a novel human protein-tyrosine kinase gene (hck) that is primarily expressed in hematopoietic cells, particularly granulocytes. The hck gene encodes a 505-residue polypeptide that is closely related to pp56lck, a lymphocyte-specific protein-tyrosine kinase. The exon breakpoints of the hck gene, partially defined by using murine genomic clones, demonstrate that hck is a member of the src gene family and has been subjected to strong selection pressure during mammalian evolution. High-level expression of hck transcripts in granulocytes is especially provocative since these cells are terminally differentiated and typically survive in vivo for only a few hours. Thus the hck gene, like other members of the src gene family, appears to function primarily in cells with little growth potential.
Complex emission dynamics from InGaAs/GaAs core-shell nanopillars (2015)

In this work, the optical properties and emission dynamics of core-shell InGaAs/GaAs nanopillars (NPs) have been in- vestigated using low-temperature photoluminescence (PL) and time-resolved photoluminescence (TRPL). These novel structures have recently attracted much interest within the silicon photonics scientific community due to their potential employment as gain medium for monolithically integrated lasers on silicon substrates. The optimization of the emission properties of these heterostructures is essential to obtain full compatibility with silicon photonics and requires an accurate tailoring of the pillar geometry (i.e. size, pitch) and composition. Therefore it is critical to gain deeper insight into the optical and dynamical properties of different NP designs if optimal device performance is to be achieved. The experimental characterization, carried out on a number of different NP structures with different geometries and compositions, shows that the time evolution of the emission peak exhibits a strong excitation-dependent blue-shift which can be attributed to the band-filling effect. Measured emission decay times were strongly geometry-dependent and varied from nanoseconds to tens of picoseconds. In addition, a dramatic reduction of the decay time was observed for the highest indium concentration due to the dominant contribution of the strain-induced non-radiative recombination processes.
Initiation of DNA replication at the primary origin of bacteriophage T7 by purified proteins. Initiation of bidirectional synthesis. (1985)

Replication of bacteriophage T7 DNA initiates in vivo at an origin located 15% of the distance from the genetic left end of the chromosome. Bidirectional DNA synthesis from this site results in complete replication of the chromosome. The combination of T7 RNA polymerase, T7 DNA polymerase, and T7 gene 4 protein initiates DNA synthesis in vitro within the cloned origin sequence (Fuller, C. W., and Richardson, C. C. (1985) J. Biol. Chem. 260: 3185-3196). DNA synthesis is primed by T7 RNA polymerase transcripts, and proceeds in the same direction (rightward) as transcription to yield partially replicated Y-form DNA molecules. The DNA product of in vitro synthesis (Y-form DNA) has been characterized by electron microscopic, sedimentation, and gel electrophoretic analyses. These studies show that Y-form DNA is the product of unidirectional replication of both leading and lagging strands from the origin to the right-hand end of the template. The inclusion of either Escherichia coli single-stranded DNA-binding protein or the functionally similar T7 gene 2.5 protein results in marked stimulation of bidirectional synthesis. Studies using purified Y-form DNA provide direct evidence that this species is an intermediate in the complete replication of the linear template. Purified Y-form DNA is converted to linear DNA in a reaction catalyzed by T7 DNA polymerase, T7 gene 4 protein, and single-stranded DNA-binding protein. Y-form DNA is a competent, transient intermediate during the bidirectional replication of linear DNA molecules and DNA-binding protein is essential to initiate leftward synthesis.
Effect of laser beam welding on microstructure, tensile strength and fatigue behaviour of duplex stainless steel 2205 (2021)

This study focuses on the microstructure, tensile and fatigue properties of laser beam welded butt joints in 4 mm thick sheets of duplex stainless steel 2205. The microstructural characteristics of the joints were investigated via optical microscopy and electron backscattered diffraction. A 300 μm wide heat affect zone with increased ferrite content and a nearly fully ferritic 800 μm wide fusion zone were found. No porosity could be found with X-ray radiography. Microhardness measurements revealed increased strength in the fusion and heat affect zones of the weldments. Uniaxial tensile and stress controlled fatigue tests were performed in order to characterize the mechanical properties of specimens containing laser beam welded joints and the base material. The specimens containing weldments were stronger, but less ductile than the base material, due to the weld metal restricting deformation. The as-welded joints exhibited worse fatigue performance than the base material due to the notch at the excess weld metal. The fatigue properties of the specimens containing joints could be elevated to the base material level by a laser surface remelting treatment.
Robust speech recognition in a multimedia teleconferencing environment (1992)

In many speech recognition systems, inconsistency between the training and testing conditions (i.e., effects related to noise, reverberation, microphone type, and characteristics, etc.) typically results in an unacceptable degradation in the recognition accuracy. For example, an experiment conducted in our multimedia laboratory demonstrated that the word accuracy of the Sphinx recognition system degrades from 96% to 71% when the close-talking Senheiser microphone (CLS) at 5 in., used in training, is replaced by a hands-free wideband line array (ARR) at 10 ft. This paper describes a neural network architecture for improving the robustness of speech recognizers in a multimedia teleconferencing environment. A multi-layer perception (MLP) is trained to map cepstral parameters from the ARR to the CLS. An experiment conducted on three male speakers using the ARR shows that a MLP with a hidden layer of eight nodes improves the recognition accuracy of the Sphinx system from 71% to 90%. Furthermore, cross-speaker validation (i.e., training on one speaker and testing on others) provided an 84% word accuracy. The encouraging result implies that the neural network ‘‘learns’’ the room reverberation characteristics and performs the environment adaptation largely irrespective of the speaker or the spoken text.
Adaptive PSP-MLSE Using State-Space Based RLS for Multi-Path Fading Channels (2008)

An adaptive per-survivor processing maximum likelihood sequence estimation (PSP-MLSE) using state-space based recursive least-squares (RLS) is proposed for rapidly time varying multi-path fading channels. Unlike PSP-MLSE using Kalman filtering, it does not require the knowledge of model statistics, and with an aid of state-space modeling, it has a robust performance to the fade rate, compared to PSP-MLSE using conventional RLS.
The electromagnetic fields of elliptical torus knots (2001)

The electromagnetic radiation and scattering properties of thin perfectly conducting knotted wires are investigated. A particular class of knots, which we call elliptical torus knots, are introduced for the purposes of this investigation. These knots derive their name from the fact that they may be constructed on the surface of a virtual torus which has an elliptical cross section. The parameterizations which describe the curves of these knots are more general than any which have been considered in previous studies and, therefore, provide more flexibility in the design of knotted wire scatterers. A moment method technique is applied to model the backscattering from an elliptical trefoil knot as a function of frequency, polarization, and incidence angle.
The Use of Light/Chemically Hardened Polymethylmethacrylate, Polyhydroxyethylmethacrylate, and Calcium Hydroxide Graft Material in Combination With Polyanhydride Around Implants in Minipigs: Part I: Immediate Stability and Function (2011)

The newly formulated chemically hardened graft material PPCH-PA was useful in immediate implant placement after tooth extraction and resulted in greater stability and a well-organized implant-bone interface with immediate loading, especially in those areas where cancellous bone was present. The results of this proof-of-concept study warranted further research investigating different healing times and longer durations.
A Simple and Convenient One‐Pot Synthesis of Fatty Acid Esters from Hindered Alcohols Using N,N‐Dimethylchlorosulfitemethaniminium Chloride as Dehydrating Agent. (2002)

Abstract For Abstract see ChemInform Abstract in Full Text.
Gendered Innovation in Cardiovascular Science: Implementation of Sex and Gender into Clinical and Biomedical Research (2013)

In many diseases male and female patients present with different symptoms. Frequently, however, no gender-sensitive diagnostics are performed and inappropriate therapeutic options may be offered. A better knowledge of gender differences in medicine could personalize treatment and increase quality of health care specifically in the area of diagnostics and consecutive treatment.[1] [2]
Allogeneic Mesenchymal Stem Cells as a Treatment for Aging Frailty (2017)

As life expectancy is projected to increase in the ensuing decades, individuals of older age continue to exceed the previous generation’s lifespan. Advancing age is associated with a reduction in physical and mental functional capacity, and chronic inflammation is a major factor contributing to this decline. A heightened inflammatory state can lead to exhaustion, weakness, weight loss, slow gate speed, and an overall decrease in activity level. These phenotypes define the onset of the disease process known as frailty. Frailty is a growing epidemic, which severely undermines a person’s ability to deal with outside stressors, and increases their rate of hospitalization, institutionalization, and mortality. Current interventions focus on preventative care by improving exercise capacity, strength, nutritional supplementation, diet, and mobility. However, a biological cure has heretofore remained elusive. Here, we introduce the novel therapeutic principle that mesenchymal stem cell (MSC) therapy may represent a safe, practical, and efficacious both the treatment and prevention of frailty in individuals of advancing age. To date, a phase I safety trial reveals an excellent safety profile and suggests that mesenchymal stem cells can ameliorate signs and symptoms of frailty. These early studies lay the groundwork for future large-scale clinical trials of this exciting and novel therapeutic concept that has the potential to expand health span in the aging population.
Structural changes in the SARS-CoV-2 spike E406W mutant escaping a clinical monoclonal antibody cocktail (2022)

The SARS-CoV-2 receptor-binding domain (RBD) E406W mutation abrogates neutralization mediated by the REGEN-CoV therapeutic monoclonal antibody (mAb) COVID-19 cocktail and the cilgavimab (AZD1061) mAb. Here, we show that this residue substitution remodels the ACE2-binding site allosterically, thereby dampening receptor recognition severely and altering the epitopes recognized by these three mAbs. Although vaccine-elicited neutralizing antibody titers are decreased similarly against the E406 mutant and the Delta or Epsilon variants, broadly neutralizing sarbecovirus mAbs, including a clinical mAb, inhibit the E406W spike mutant.
Membrane Orientation and Subcellular Localization of Transmembrane Protein 106B (TMEM106B), a Major Risk Factor for Frontotemporal Lobar Degeneration (2012)

TMEM106B was identified as a major risk factor in a genome-wide association study for frontotemporal lobar degeneration (FTLD) with TAR DNA-binding protein (TDP)-43 pathology. The most significant association of TMEM106B single nucleotide polymorphisms with risk of FTLD-TDP was observed in patients with progranulin (GRN) mutations. Subsequent studies suggested an inverse correlation between TMEM106B expression and GRN levels in patient serum. However, in this study, this was not confirmed as we failed to detect a significant alteration of GRN levels upon knockdown or exogenous expression of TMEM106B in heterologous cells. To provide a basis for understanding TMEM106B function in health and disease, we investigated the membrane orientation and subcellular localization of this completely uncharacterized protein. By differential membrane extraction and sequential mutagenesis of potential N-glycosylation sites, we identified TMEM106B as a type 2 integral membrane protein with a highly glycosylated luminal domain. Glycosylation is partially required for the transport of TMEM106B beyond the endoplasmic reticulum to late cellular compartments. Endogenous as well as overexpressed TMEM106B localizes to late endosomes and lysosomes. Interestingly, the inhibition of vacuolar H(+)-ATPases significantly increased the levels of TMEM106B, a finding that may provide an unexpected biochemical link to GRN, because this protein is also strongly increased under the same conditions. Our findings provide a biochemical and cell biological basis for the understanding of the pathological role of TMEM106B in FTLD, an incurable neurodegenerative disorder.
Response to Comment on "Evidence for Positive Epistasis in HIV-1" (2006)

Wang et al . analyzed artificially biased data to show that our results can be explained by a bias against sequences with low fitness. We explicitly acknowledged this potential caveat in our original study. Showing that an artificially introduced bias can produce a spurious signal of positive epistasis does not demonstrate that such bias exists in our original data.
Feed Forward Control for Pneumatic Forearm Prosthesis, Manipulator (2012)

In order to reach a better productivity in numerous fields, robots have been wildly used for automatic tasks. The main issue of a robot is his lack of adaptability, which is one of the most important ability of human beings. The best tool for adaptability is the human hand. Using pneumatic actuators to drive a robot forearm grants the possibility to move light articles with accuracy and without harming it. It is then necessary to develop accurate model of the different types of actuators. As every human muscle are simulated by those actuators, the size of these must vary and so their properties as well. These artificial muscle-type pneumatic actuators are composed of a rubber balloon, a net, a feeding channel and finally two anchors at both end of the net. Starting with the simplest linear model, we increased the complexity of the model to finally obtain a powerful control of the plastic muscle. To obtain the data we needed for the model, we used a test bench for pneumatic actuators and adjust it to fit the new size of the current actuator. The main difficulty to control the actuator is to find a way to overcome its hysteresis cycle. Then once the model is ready we need to use it to control the different part of the pneumatic forearm. The previous wrist and hand control is enhanced by feed forward control and can perform motion with a great accuracy. The hand can therefore be used without any electronic devices on it and remains lighter and safer. Previous starting dead-zone has been understood and avoided.
Performance of delay diversity with subcarrier-based signal phase rotation in OFDM system (2010)

This paper investigates the performance of delay diversity with subcarrier-based signal phase rotation in an OFDM system. Delay diversity achieves transmit diversity with channel coding by intentionally ingenerating paths which have different delays at a transmitter side. However, the correlation between subcarriers is not always low. The proposed scheme which combines the delay diversity and the phase rotation of the transmit signal offers diversity gain by reducing the correlation between the specific combination of the subcarriers. It is shown through computer simulation that the proposed scheme improves the BER performance by about 2 dB with a repetition code.
Enzymatic Synthesis of a Novel Trisaccharide, Glucosyl Lactoside (1993)

Cyclomaltodextrin glucanotransferase from Bacillus stearothermophilus produced a series of oligosaccharides by the transglycosylation reaction with cyclomaltohexaose as a glycosyl donor and D-lactose as its acceptor. The content of oligosaccharide A as the main transfer product was 22.1% of the total sugar. The content was increased to 34.1% by hydrolysis with glucoamylase. Oligosaccharide A was isolated by column chromatography and crystallized. By chemical and enzymatic analyses, oligosaccharide A was found to be a novel non-reducing trisaccharide; O-beta-D-galactopyranosyl-(1-->4)-O- beta-D-glucopyranosyl alpha-D-glucopyranoside.
Recombinant human sperm-specific glyceraldehyde-3-phosphate dehydrogenase (GAPDHS) is expressed at high yield as an active homotetramer in baculovirus-infected insect cells (2020)

The sperm-specific glyceraldehyde-3-phosphate dehydrogenase (GAPDHS) isoform is a promising contraceptive target because it is specific to male germ cells, essential for sperm motility and male fertility, and well suited to pharmacological inhibition. However, GAPDHS is difficult to isolate from native sources and recombinant expression frequently results in high production of insoluble enzyme. We chose to use the Bac-to-Bac baculovirus-insect cell system to express a His-tagged form of human GAPDHS (Hu his-GAPDHS) lacking the proline-rich N-terminal sequence. This recombinant Hu his-GAPDHS was successfully produced in Spodoptera frugiperda 9 (Sf9) cells by infection with recombinant virus as a soluble, enzymatically active form in high yield, >35mg/L culture. Biochemical characterization of the purified enzyme by mass spectrometry and size exclusion chromatography confirmed the presence of the tetrameric form. Further characterization by peptide ion matching mass spectrometry and Edman sequencing showed that unlike the mixed tetramer forms produced in bacterial expression systems, human his-GAPDHS expressed in baculovirus-infected insect cells is homotetrameric. The ability to express and purify active human GAPDHS as homotetramers in high amounts will greatly aid in drug discovery efforts targeting this enzyme for discovery of novel contraceptives and three compounds were identified as inhibitors of Hu his-GAPDHS from a pilot screen of 1120 FDA-approved compounds.
Event-triggered Feedback Control for Signal Temporal Logic Tasks (2020)

A framework for the event-triggered control synthesis under signal temporal logic (STL) tasks is proposed. In our previous work, a continuous-time feedback control law was designed, using the prescribed performance control technique, to satisfy STL tasks. We replace this continuous-time feedback control law by an event-triggered controller. The event-triggering mechanism is based on a maximum triggering interval and on a norm bound on the difference between the value of the current state and the value of the state at the last triggering instance. Simulations of a multi-agent system quantitatively show the efficacy of using an event-triggered controller to reduce communication and computation efforts.