gebhart/patrepeval huggingface dataset:
Laser-Irradiation-Induced Enrichment of Metallic Single-Walled Carbon Nanotubes from As-Synthesized Nanotubes Individually Dispersed in Aqueous Solution (2012)

In the present study, we developed a novel technique for the enrichment of metallic (m-) single-walled carbon nanotubes (SWNTs) from as-synthesized SWNTs that are individually dispersed in carboxymethylcellulose (CMC) aqueous solution by irradiation with a nanosecond-pulsed optical parametric oscillator (OPO) laser with wavelength tunability. The 507 nm laser irradiation in the m-SWNT first-transition band (M 11 ) resulted in the collapse of both m- and semiconducting (s-) SWNTs. In contrast, the irradiation with a laser with a wavelength (778 or 989 nm) corresponding to the typical absorption peaks in the s-SWNT second (S 22 )- or first (S 11 )-transition bands caused a preferential collapse of s-SWNTs, resulting in enriched m-SWNTs of high purity and in large quantity. The present m-SWNT collection technique can be generalized for various SWNT dispersion systems using different dispersing agents. The OPO laser irradiation discussed in this study is a promising technique for the selective separation of dispersed m-SWNTs.
Microvesicles as Cell–Cell Messengers in Cardiovascular Diseases (2014)

Cell-cell communication has proven to be even more complex than previously thought since the discovery that extracellular vesicles serve as containers of biological information on various pathophysiological settings. Extracellular vesicles are classified into exosomes, microvesicles/microparticles, or apoptotic bodies, originating from different subcellular compartments. The cellular machinery controlling their formation and composition, as well as the mechanisms regulating their extracellular release, remain unfortunately much unknown. Extracellular vesicles have been found in plasma, urine, saliva, and inflammatory tissues. Their biomarker potential has raised significant interest in the cardiovascular field because the vesicle composition and microRNA content are specific signatures of cellular activation and injury. More than simply cell dust, extracellular vesicles are capable of transferring biological information to neighboring cells and play an active role in inflammatory diseases, including atherosclerosis and angiogenesis. The molecular interactions regulating these effects involve specific receptor activation, proteolytic enzymes, reactive oxygen species, or delivery of genetic information to target cells. Unraveling their mechanisms of action will likely open new therapeutic avenues.
Plasma polymerization of 1-benzothiophene (1991)

Semiconductive thin organic polymer films have been prepared by the plasma polymerization of 1-benzothiophene. Characteristics of the polymeric products such as their electrical conductivities, optical properties, and electron spin properties have been examined in detail. Doping of these films with iodine has resulted in an increase in electrical conductivity by eight to nine orders of magnitude. The molecular structure of the products has also been discussed.
Interligand Overhauser Effects in Type II Dihydrofolate Reductase (2001)

R67 dihydrofolate reductase (DHFR) is a type II DHFR produced by bacteria as a resistance mechanism to the increased clinical use of the antibacterial drug trimethoprim. Type II DHFRs are not homologous in either sequence or structure with chromosomal DHFRs. The type II enzymes contain four identical subunits which form a homotetramer containing a single active site pore accessible from either end. Although the crystal structure of the complex of R67 DHFR with folate has been reported [Narayana et al. (1995) Nat. Struct. Biol. 2, 1018], the nature of the ternary complex which must form with substrate and cofactor is unclear. We have performed transferred NOE and interligand NOE (ILOE) studies to analyze the ternary complexes formed from NADP(+) and folate in order to probe the structure of the ternary complex. Consistent with previous studies of the binary complex formed from another type II DHFR, the ribonicotinamide bond of NADP(+) was found to adopt a syn conformation, while the adenosine moiety adopts an anti conformation. Large ILOE peaks connecting NADP(+) H4 and H5 with folate H9 protons are observed, while the absence of a large ILOE connecting NADP(+) H4 and H5 with folate H7 indicates that the relative orientation of the two ligands differs significantly from the orientation in the chromosomal enzyme. To obtain more detailed insight, we prepared and studied the folate analogue 2-deamino-2-methyl-5,8-dideazafolate (DMDDF) which contains additional protons in order to provide additional NOEs. For this analogue, the exchange characteristics of the corresponding ternary complex were considerably poorer, and it was necessary to utilize higher enzyme concentrations and higher temperature in order to obtain ILOE information. The results support a structure in which the NADP(+) and folate/DMDDF molecules extend in opposite directions parallel to the long axis of the pore, with the nicotinamide and pterin ring systems approximately stacked at the center. Such a structure leads to a ternary complex which is in many respects similar to the gas-phase theoretical calculations of the dihydrofolate-NADPH transition state by Andres et al. [(1996) Bioorg. Chem. 24, 10-18]. Analogous NMR studies performed on folate, DMDDF, and R67 DHFR indicate formation of a ternary complex in which two symmetry-related binding sites are occupied by folate and DMDDF.
Nitrations and oxidations with inorganic nitrate salts in trifluoroacetic anhydride (1981)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNitrations and oxidations with inorganic nitrate salts in trifluoroacetic anhydrideJ. V. CrivelloCite this: J. Org. Chem. 1981, 46, 15, 3056–3060Publication Date (Print):July 1, 1981Publication History Published online1 May 2002Published inissue 1 July 1981https://doi.org/10.1021/jo00328a013RIGHTS & PERMISSIONSArticle Views2343Altmetric-Citations142LEARN 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 InReddit PDF (574 KB) Get e-Alertsclose Get e-Alerts
ChemInform Abstract: AN UNAMBIGUOUS SYNTHESIS OF MELANNEIN (1982)

Abstract Aus den Dihydroxyacetophenonderivaten (I) sind mit Diethylcarbonat (II) die Benzoylessigsäureester (III) zugänglich, die mit Brenzcatechinmonomethylether (IV) zu den Lactonen (V) cyclisieren.
Enzymic Generation of Volatile Aroma Compounds from Fresh Fish (1986)

Characterizing aromas for freshly-harvested fish are derived from polyunsaturated fatty acids through lipoxygenase-mediated reactions, and include both volatile alcohols and carbonyls. Short-chain alcohols and aldehydes were shown to suppress the activity of lipoxygenase which was derived from trout gill tissue, and may serve as a means to regulate the formation of fresh fish aroma compounds. Exploratory experiments revealed that plant-derived lipoxygenases have potential for the biogenesis of fresh fish flavors.
The methylation patterns of chromosomal integration regions influence gene activity of transferred DNA in <i>Petunia hybrida</i> (1992)

The regions of integration of a transferred DNA-fragment from three transgenic Petunia hybrida plants were analysed for their influence on the expression of the foreign DNA. Each of the three transformants, lines 16, 17 and 24, contained a fragment of a plasmid on which two genes were located, an npt-II gene which renders the plants resistant to kanamycin and the A1 gene from Zea mays, a visible marker gene that leads to the production of a brick red anthocyanin pigment in the flowers. Inactivation of both genes in line 16 is associated with integration into a region of highly repetitive DNA, while the integration sites of the other two lines were essentially unique. The integration regions of lines 17 and 24, both of which show expression of the foreign genes at characteristically different intensities, showed a distinct methylation pattern that was stably conserved for these regions in both transgenic and wild-type plants. The characteristic methylation pattern of the two integration regions was also imposed on the border region of the integrated fragments and might thus be responsible for the differences in the intensity of gene expression observed among the two lines.
Joint digitalization scheme for multiband GNSS receivers (2015)

A digitalization scheme for multi-band GNSS receivers employing a single A/D converter for all signals is presented. Theoretical analyses are carried out, to compute the degradation in post-correlation signal to noise ratio due to joint filter and digitalization, in comparison to a classic scheme with separate A/D converters for each band. As a case study, a GPS and GLONASS L1 receiver is considered. The intermediate and sampling frequencies and the number of bits for the converter are designed. Also, the loss analysis is extended to a scheme with digital filter and decimation followed by requantization, in order to reduce the sample rate and number of quantization bits to values that allow a simpler implementation of the following digital processing stages. The results show that with a sampling frequency slightly above the double of that necessary in a classic scheme, the losses of the single converter scheme proposed are of the order of 1 dB greater than those of the separate converters scheme.
Occurrence of Gas-Bubble Disease in Three Species of Bivalve Molluscs (1972)

Gas-bubble disease was observed in adult oysters and hard clams held in heated running sea water during the winter. Heating the cold sea water in closed heat exchangers caused it to become supersaturated with atmospheric gases. Exposure of the animals to this water caused the formation of gas-filled conchiolin blisters on the valves of the oysters. Bubbles of gas were observed in the gill filaments of the oysters and clams and in the mantle tissue of the oysters. Any method, such as the use of baffles or an aerated head tank, that reduces the dissolved gas concentration in the water will help prevent the disease.
Wireless video transport using conditional retransmission and low-delay interleaving (2002)

We consider the scenario of using Automatic Repeat reQuest (ARQ) retransmission for two-way low-bit-rate video communications over wireless Rayleigh fading channels. A low-delay constraint may require that a corrupted retransmitted packet not be retransmitted again, thus there will be packet-errors at the decoder which results in video quality degradation. In this paper. We propose a scheme to improve the video quality. First, we propose a low-delay interleaving scheme that combines the interleaving memory with the video encoder buffer. Second, we propose a conditional retransmission strategy that reduces the number of retransmissions. Simulation results show that our proposed scheme can effectively reduce the number of packet errors and improve the channel utilization. As a result, we obtain PSNR (Peak Signal to Noise Ratio) improvement up to about 4 dB compared to H.263 TMN8.
Electronic and vibrational properties of nickel sulfides from first principles (2007)

We report the results of first-principles calculations (generalized gradient approximation-Perdew Wang 1991) on the electronic and vibrational properties of several nickel sulfides that are observed on Ni-based anodes in solid oxide fuel cells (SOFCs) upon exposure to H2S contaminated fuels: heazlewoodite Ni3S2, millerite NiS, polydymite Ni3S4, and pyrite NiS2. The optimized lattice parameters of these sulfides are within 1% of the values determined from x-ray diffraction. The electronic structure analysis indicates that all Ni-S bonds are strongly covalent. Furthermore, it is found that the nickel d orbitals shift downward in energy, whereas the sulfur p orbitals shift upward with increasing sulfur content; this is consistent with the decrease in conductivity and catalytic activity of sulfur-contaminated Ni-based electrodes (or degradation in SOFC performance). In addition, we systematically analyze the classifications of the vibrational modes at the point from the crystal symmetry and calculate the corresponding vibrational frequencies from the optimized lattice constants. This information is vital to the identification with in situ vibrational spectroscopy of the nickel sulfides formed on Ni-based electrodes under the conditions for SOFC operation. Finally, the effect of thermal expansion on frequency calculations for the Ni3S2 system is also briefly examined.
High Internal Phase Emulsions: Catastrophic Phase Inversion, Stability, and Triggered Destabilization (2011)

We have investigated the formation, drop sizes, and stability of emulsions prepared by hand shaking in a closed vessel in which the emulsion is in contact with a single type of surface during its formation. The emulsions undergo catastrophic phase inversion from oil-in-water (o/w) to water-in-oil (w/o) as the oil volume fraction is increased. We find that the oil volume fraction required for catastrophic inversion exhibits a linear correlation with the oil-water-solid surface contact angle. W/o high internal phase emulsions (HIPEs) prepared in this way contain water drops of diameters in the range 10-100 μm; emulsion drop size depends on the surfactant concentration and method of preparation. W/o HIPEs with large water drops show water separation but w/o HIPEs with small water drops are stable with respect to water separation for more than 100 days. The destabilization of the w/o HIPEs can be triggered by either evaporation of the oil continuous phase or by contact the emulsion with a solid surface of the "wrong" wettability.
Definition of REST web services with JSON schema (2016)

Summary The Web has evolved from being a collection of documents to a collection of interconnected services that interoperate throughout the Internet. Web services are a natural consequence of this evolution. The web services model was initially centered around the eXtensible Markup Language (XML). Such services can be described by Web Services Description Language documents that are formally defined through the XML Schema Definition language. However, in recent years the popularity of XML‐based web services has declined, as more developers favor JavaScript Object Notation (JSON)‐based alternatives. Although the use of the latter language is spreading, no official standard to formally describe JSON documents exists. The aim of this article is to demonstrate how JSON Schema, and particularly the JSON Hyper Schema extension, is suitable to describe JSON‐based web services that follow the REST architectural pattern. Copyright © 2016 John Wiley & Sons, Ltd.
Implementation of an Advanced Authentication Method within Microsoft Active Directory Network Services (2010)

This paper describes a new approach for developing and implementing an advanced authentication method within active directory network services. For advance authentication process a new type of user multi-factor authentication based on the classical three-factor authentication extended by the position information and time is described in this paper. The main objectives of our applied research are extended security features for more robust and more secure user's authentication process. Application scenario of advanced multi-factor authentication method within corporate networks based on the Microsoft Active Directory network services is presented. Five different factors for user's authentication provide more secured access control layer for current corporate networks with Microsoft Active Directory with only small implementation costs.
Piezoelectrically induced optical phase modulation of light in single-mode fibers (1992)

Optical phase modulation induced in piezoelectric copolymer, vinylidene fluoride (73 mol.%)/trifluoroethylene (27 mol.%), coated single-mode fibers has been examined and analyzed from both experimental and theoretical aspects. High-sensitive phase modulation, which is more than four times as large as those of vinylidene fluoride/tetrafluoroethylene copolymer, is obtained over a flat response range from 10 kHz to 3 MHz. At frequencies below 7 kHz and higher than 6 MHz the optical responses are dominated by axial and radial resonances, respectively, of the fiber-jacket composite. The theoretical prediction on induced phase shifts at high frequencies is carried out based on radial vibration analysis and followed by the experimental results.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Efficient blue‐green‐emitting poly[(5‐diphenylamino‐1,3‐phenylenevinylene)‐<i>alt</i>‐(2,5‐dihexyloxy‐1,4‐phenylenevinylene)] derivatives: Synthesis and optical properties (2006)

Abstract New poly(phenylene vinylene) derivatives with a 5‐diphenylamino‐1,3‐phenylene linkage (including polymers 2 , 3 , and 5 ) have been synthesized to improve the charge‐injection properties. These polymers are highly photoluminescent with fluorescent quantum yields as high as 76% in tetrahydrofuran solutions. With effective π‐conjugation interruption at adjacent m ‐phenylene units, chromophores of different conjugation lengths can be incorporated into the polymer chain in a controllable manner. In polymer 2 , the structural regularity leads to an isolated, well‐defined emitting chromophore. Isomeric polymer 3 of a random chain sequence, however, allows the effective emitting chromophores to be joined in sequence by sharing a common m ‐phenylene linkage (as shown in a molecular fragment). Double‐layer light‐emitting‐diode devices using 2 , 3 , and 5 as emitting layers have turn‐on voltages of about 3.5 V and produce blue‐green emissions with peaks at 493, 492, and 482 nm and external quantum efficiencies up to 1.42, 0.98, and 1.53%, respectively. In comparison with a light‐emitting diode using 2 , a device using 3 shows improved charge injection and displays increased brightness by a factor of ∼3 to 1400 cd/m 2 at an 8‐V bias. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2307–2315, 2006
High grade primitive neuroectodermal tumor of the uterus: A case report (2013)

•Primitive neuroectodermal tumor of the uterus is extremely rare.•Diagnosis requires timely evaluation with molecular analysis.•Different combinations of adjuvant chemotherapy have been reported.
Common Control Channel Security Framework for Cognitive Radio Networks (2009)

Cognitive radio networks are becoming an increasingly important part of the wireless networking landscape due to the ever-increasing scarcity of spectrum resources. Such networks perform co-operative spectrum sensing to find white spaces and apply policies to determine when and in which bands they may communicate. In a typical MAC protocol designed for cooperatively communicating ad hoc cognitive radio networks, nodes make use of a common control channel to perform channel negotiations before any actual data transmission. The provision of common control channel security is vital to ensure any subsequent security among the communicating cognitive radio nodes. To date, wireless security has received little attention in cognitive radio networks research. The cognitive radio paradigm introduces entirely new classes of security threats and challenges, such as selfish misbehaviours, licensed user emulation and eavesdropping. This paper presents a novel framework for providing common control channel security for co-operatively communicating cognitive radio nodes. To the best of the authors' knowledge, this is the first paper which proposes such a concept. The paper investigates how two cognitive radio nodes can authenticate each other prior to any confidential channel negotiations to ensure subsequent security against attacks. The paper also describes the importance of common control channel security and concludes with future work describing the realization of the proposed framework.
Biocomposite nanofibres and osteoblasts for bone tissue engineering (2007)

10.1088/0957-4484/18/5/055101
Autoantibodies to the constitutive 73-kD member of the hsp70 family of heat shock proteins in systemic lupus erythematosus. (1988)

Serum from patients with systemic lupus erythematosus (SLE) frequently contain IgM and IgG autoantibodies to the constitutively expressed 73-kD/pI 5.5 member of the hsp70 family of heat shock proteins, as determined by one-dimensional (SDS-PAGE) and two-dimensional (IEF/SDS-PAGE) immunoblotting, and by solid-phase SLE Ig immunoprecipitation experiments using hsp70 protein-specific mAbs as probes. Autoantibodies to hsp70 also were detected in a minority of sera from patients with other rheumatic or viral diseases, but not in normal sera. These data may provide additional insight into etiologic and pathophysiologic mechanisms in this and related autoimmune disorders.
Magnetic nanoparticles: preparation, physical properties, and applications in biomedicine (2012)

Finally, we have addressed some relevant findings on the importance of having well-defined synthetic strategies developed for the generation of MNPs, with a focus on particle formation mechanism and recent modifications made on the preparation of monodisperse samples of relatively large quantities not only with similar physical features, but also with similar crystallochemical characteristics. Then, different methodologies for the functionalization of the prepared MNPs together with the characterization techniques are explained. Theorical views on the magnetism of nanoparticles are considered.
Effects of GeO <sub>2</sub> Addition on Sintering and Properties of (K <sub>0.5</sub> Na <sub>0.5</sub> )NbO <sub>3</sub> Ceramics (2016)

Lead‐free (K 0.5 Na 0.5 )NbO 3 ( KNN ) piezoelectric ceramics doped with different amounts of GeO 2 were prepared and characterized. GeO 2 was found to effectively improve the sinterability and piezoelectric properties of the material. The improvement in the sinterability is ascribed to the formation of a liquid phase, which decreased the sintering temperature from 1080°C to 1010°C. The improvement in the properties is attributed to the replacement of Nb 5+ with Ge 4+ to form acceptor dopants. The following optimized properties were obtained from the KNN ceramic with 0.75 wt% GeO 2 : piezoelectric constant ( d 33 ) = 126 pC /N, planar electromechanical coupling coefficient ( k p ) = 42.8%, mechanical quality factor ( Q m ) = 140, and dielectric loss (tanδ) = 3.8%.