gebhart/patrepeval huggingface dataset:
Sterols. IV. Δ<sup>20</sup>-Pregnenes from bisnor-Steroid Acids (1948)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSterols. IV. Δ20-Pregnenes from bisnor-Steroid AcidsPercy L. Julian, Edwin W. Meyer, and Helen C. PrintyCite this: J. Am. Chem. Soc. 1948, 70, 3, 887–892Publication Date (Print):March 1, 1948Publication History Published online1 May 2002Published inissue 1 March 1948https://pubs.acs.org/doi/10.1021/ja01183a001https://doi.org/10.1021/ja01183a001research-articleACS PublicationsRequest reuse permissionsArticle Views138Altmetric-Citations31LEARN 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 optionsGet e-Alertsclose Get e-Alerts
Self-Assembled Micelles Composed of Doxorubicin Conjugated Y-Shaped PEG-Poly(glutamic acid)2 Copolymers via Hydrazone Linkers (2014)

In this work, micelles composed of doxorubicin-conjugated Y-shaped copolymers (YMs) linked via an acid-labile linker were constructed. Y-shaped copolymers of mPEG-b-poly(glutamate-hydrazone-doxorubicin)2 and linear copolymers of mPEG-b-poly(glutamate-hydrazone-doxorubicin) were synthesized and characterized. Particle size, size distribution, morphology, drug loading content (DLC) and drug release of the micelles were determined. Alterations in size and DLC of the micelles could be achieved by varying the hydrophobic block lengths. Moreover, at fixed DLCs, YMs showed a smaller diameter than micelles composed of linear copolymers (LMs). Also, all prepared micelles showed sustained release behaviors under physiological conditions over 72 h. DOX loaded in YMs was released more completely, with 30% more drug released in acid. The anti-tumor efficacy of the micelles against HeLa cells was evaluated by MTT assays, and YMs exhibited stronger cytotoxic effects than LMs in a dose- and time-dependent manner. Cellular uptake studied by CLSM indicated that YMs and LMs were readily taken up by HeLa cells. According to the results of this study, doxorubicin-conjugated Y-shaped PEG-(polypeptide)2 copolymers showed advantages over linear copolymers, like assembling into smaller nanoparticles, faster drug release in acid, which may correspond to higher cellular uptake and enhanced extracellular/intracellular drug release, indicating their potential in constructing nano-sized drug delivery systems.
Electrochemical and Corrosion Fatigue Behavior of FeAlMn Alloys in NaCl Solution (1988)

The electrochemical polarization and corrosion fatigue behavior of the austenitic Fe-8.25Al-29.95Mn-0.85C and Fe-9.33Al-25.94Mn-1.45C alloys in NaCl solutions have been investigated. Potentiodynamic polarization tests in aqueous solution containing 0.005 to 10.0 wt% NaCl in the pH range of 2 to 6 have been conducted. Experimental results showed that the electrochemical parameters, such as corrosion potential and anodic current density, as well as the passivation properties, depended upon the pH and the chloride ion concentration of the solution. In 3.5 wt% NaCl solution, no passive region was observed if the pH was &lt;3. Meanwhile, the pitting potential of the FeAlMn alloys increased with decreasing chloride ion concentration. Fatigue crack growth (FCG) rates of the FeAlMn alloys, either in air or in 3.5 wt% NaCl solution at 25 C, were measured using center-cracked specimens. Sinusoidal load at a R ratio of 0.1 was applied with a frequency of 1 or 5 Hz. The experimental results showed that the FeAlMn alloys had better fatigue resistance than AISI(1) 316 stainless steel (SS) in air. The FCG rates at ΔK=20MPam and at 5 Hz ranked in the following order: AISI 316 SS &gt; Fe-8.25Al-29.95Mn-0.85C (aged at 550 C/4 h) &gt; Fe-9.33Al-25.94Mn-1.45C (solution annealed) &gt; Fe-8.25Al-29.95Mn-0.85C (solution annealed). Environmental enhancement on the FCG rates for both solution-annealed FeAlMn alloys tested in 3.5 wt% NaCl solution at 25 C was observed. The environmental effect became more evident as the testing frequency decreased from 5 to 1 Hz. For the aged Fe-8.25Al-29.95Mn-0.85C alloy, however, the FCG rates in 3.5% NaCl solution were higher at 5 Hz than at 1 Hz.
Anisotropic Reactive Ion Etching of MoSi2 and In Situ Doped n+ and p+ Polysilicon Using Cl2 and BCl3 (1988)

Mise au point d'un procede de gravure ionique reactive a haute resolution par Cl 2 /BCl 3 permettant la gravure simultanee de structures composites en MoSi 2 et silicium polycristallin dope non recuit
Determination of Antibacterial Mode of Action of <i><scp>A</scp>llium sativum</i> Essential Oil against Foodborne Pathogens Using Membrane Permeability and Surface Characteristic Parameters (2013)

Abstract This study investigates the antibacterial mechanism of action of A llium sativum rhizome essential oil ( ASEO ) against foodborne pathogens. The ASEO was obtained by hydrodistillation of A . sativum rhizome using a microwave‐assisted extraction technique. The ASEO (1,000 μg/disk) showed potential antibacterial effect as diameters of inhibition zones against the tested foodborne pathogens including American Type Culture Collection (ATCC) strains B acillus cereus ATCC 13061, E scherichia coli ATCC 43889, L isteria monocytogenes ATCC 7644, Salmonella Typhimurium ATCC 43174 and S taphylococcus aureus ATCC 12600, which were found in the range of 11.0 ± 0.1–24.0 ± 0.1 mm. The minimum inhibitory concentration ( MIC ) and minimum bactericidal concentration ( MBC ) values of ASEO against the tested bacteria were found in the range of 62.5–500 μg/mL. At the MIC concentration, ASEO had potential inhibitory effect on the cell viability of the tested bacteria. In addition, the scanning electron microscopy analysis showed the inhibitory effect of ASEO as confirmed by the considerable morphological alterations on the cell walls of B . cereus ATCC 13061 and E . coli ATCC 43889. Moreover, the ASEO revealed its mode of action on membrane integrity as confirmed by the release of extracellular adenosine 5′‐triphosphate, 260‐nm absorbing materials and potassium ions efflux against tested pathogens. These findings suggest that ASEO showed its effect on membrane permeability and surface characteristics. Practical Applications Foodborne pathogens are the leading causes of illness in the developed countries. These pathogens are responsible for millions of cases of infectious diseases each year, costing billions of dollars in medical care. New foodborne pathogens and foodborne diseases are likely to emerge driven by factors such as pathogen evolution, changes in food manufacturing practices, and changes to the human host status. Fuelled by these concerns, research on biologically active natural compounds to control the foodborne pathogens has escalated to unprecedented levels in recent years. Plant‐based antimicrobials such as essential oils have been found to suppress the growth of foodborne pathogens in various in vitro and in vivo models. These findings clearly indicate that essential oil derived from the rhizome of A . sativum confers its mode of action on membrane integrity, hence, could be used as an affective candidate to control the growth of certain important foodborne pathogens in practical applications.
UV‐INDUCED PROTEIN ALTERATIONS AND LIPID OXIDATION IN ERYTHROCYTE MEMBRANES (1990)

Certain ultraviolet radiation-induced effects in skin may result from primary photochemical alterations in cell membranes. We have studied isolated erythrocyte membranes in order to determine the UV-fluence and wavelength dependence for protein alterations and lipid oxidation. Protein crosslinking was detected as high molecular weight protein (greater than 200,000 DA) on polyacrylamide/agarose gel electrophoresis. Spectrin decreased more rapidly than the other membrane proteins upon exposure to lambda = 250-380 nm radiation. Nitrogen-purging inhibited the UV-induced decrease in spectrin by 60% and decreased crosslinking to an even greater degree. The decrease in spectrin was not inhibited by superoxide dismutase, catalase, or sodium azide. Radiation at 280 nm was most effective for spectrin loss, 265 and 297 nm were less effective and 254 and 313 nm were not effective. Prior irradiation at 280 nm did not sensitize the membranes to subsequent irradiation at 313 nm indicating that photodecomposition products of tryptophan are not involved. Lipid photooxidation was measured with the thiobarbituric acid assay and was induced at higher fluences of UV radiations than those required for loss of spectrin. These results indicate that the major effects of UV radiation on cell membranes are alterations of proteins and suggest that tryptophan is the major chromophore for these alterations.
On the involvement of NHC carbenes in catalytic reactions by iridium complexes, nanoparticle and bulk metal dispersed in imidazolium ionic liquids (2007)

D/H exchange reactions at C2, C4 and C5 of the imidazolium cation were observed in catalytic hydrogenation reactions promoted by classical Ir(I) colloid precursors and [Ir(0)](n) nanoparticles dispersed in deuterated imidazolium ionic liquids indicating the participation of carbene species in this media. However, no D/H exchange reaction was observed in cyclohexene hydrogenation promoted by iridium bulk metal dispersed in the ionic liquid [BMI]-d(3).NTf(2). The D/H labeling experiments suggest that the ionic liquids interact with the metal centers preferentially as aggregates rather than isolated ions.
A high-temperature prototype instrument for downhole acoustic sensing (1984)

This paper presents the design for an acoustic instrument which can operate at frequencies of 10–40 kHz and temperatures up to 250°C. It first introduces a high-temperature circuit using Sandia's Sprytron switching tube and an over-voltage gap. Next, the high-temperature performance of a 2-V Permendur magnetostrictive transducer (for the transmitter), and a piezoelectric material (for the receiver) is described. The problems encountered and the corresponding solutions are revealed. The design of an acoustic isolator and the mechanical housing of this instrument are presented.
Mini, Micro, and Swarming Unmanned Aerial Vehicles: A Baseline Study (2006)

Abstract : This report describes worldwide technological developments in miniature (mini) and micro unmanned aerial vehicles (UAVs), including swarming capabilities, flapping-wing, vertical-takeoff-and-landing, and tilt-rotor UAVs. In particular, the report describes trends in mini and micro UAV development, their technical capabilities and limitations, military and nonmilitary uses of UAVs, and the size of the worldwide UAV market. The appendix lists mini and micro UAVs produced in selected countries. The report draws on conference presentations, reports, journal articles, and manufacturer Web sites from around the world in English and other languages.
Microcellular Polyurethane Elastomers as Damping Elements in Automotive Suspension Systems (1991)

<div class="htmlview paragraph">Microcellular cast polyurethane (MC-PUR) elastomers and rubber are widely used as damping components in automobile suspension systems.</div> <div class="htmlview paragraph">MC-PUR materials have the following advantages over rubber:</div> <div class="htmlview paragraph"> <ul class="list disc"> <li class="list-item"> <div class="htmlview paragraph">High volume compressibility</div> </li> <li class="list-item"> <div class="htmlview paragraph">Lighter weight</div> </li> <li class="list-item"> <div class="htmlview paragraph">Better flexibility</div> </li> <li class="list-item"> <div class="htmlview paragraph">Small size</div> </li> <li class="list-item"> <div class="htmlview paragraph">Resistance to dynamic fatigue</div> </li> </ul> </div> <div class="htmlview paragraph">The handling of the vehicle can be improved by using MC-PUR helper springs rather than buffers. These spring elements require a MC-PUR elastomer with excellent dynamic performance.</div> <div class="htmlview paragraph">Naphthalene- 1.5-diisocyanate (NDI) has proved to be the most suitable raw material for this very demanding application. The properties of MC-PUR springs based on NDI are discussed in comparison to other elastomeric materials.</div>
Test and evaluation by genetic algorithms (1993)

A machine learning technique for automating the traditional controller tests process that evaluates autonomous-vehicle software controllers is discussed. In the proposed technique, a controller is subjected to an adaptively chosen set of fault scenarios in a vehicle simulator, and then a genetic algorithm is used to search for fault combinations that produce noteworthy actions in the controller. This approach has been applied to find a minimal set of faults that produces degraded vehicle performance and a maximal set of faults that can be tolerated without significant performance loss.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The Doctor's PDA and Smartphone Handbook: Medical references (2006)

This is the fourth in a series of extracts from a forthcoming book by M Al-Ubaydli and C Paton. The website [www.rsmpress.co.uk/bkpda.htm] includes video tutorials to accompany this text.
Constraint based audio interpolators (2002)

In audio digital signal processing, interpolators are used for a variety of functions, including sample rate conversion. Linear interpolation is commonly used, but has serious signal quality problems for signals with significant high frequency content. Higher order interpolators based on sine functions or other conventional lowpass filter design techniques offer somewhat better performance, but are not optimal in terms of perceived audio performance for a given degree of computational complexity. We present a new technique for the design of higher order interpolators for digital audio which provides improved performance at a given degree of complexity. Also presented are new methods for evaluating audio interpolators.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Assessment of resveratrol bioavailability in the perfused small intestine of the rat. (2000)

Resveratrol, which is present in grapes, wine and peanuts, is believed to possess chemoprotective properties such as anticarcinogenic effects and to provide protection against cardiovascular diseases. Little is known, however, about its intestinal absorption. We investigated the absorption and metabolism of resveratrol by using an isolated preparation of luminally and vascularly perfused rat small intestine. A synthetic perfusate free from blood components was used as vascular medium with a perfluorocarbon as oxygen carrier. Luminal media consisted of a bicarbonate buffered sodium chloride solution spiked with resveratrol in physiological, nutritionally relevant concentrations (28, 34 and 57 micromol/l, respectively). Viability was maintained during the entire perfusion and no significant differences between resveratrol and control perfusions for oxygen consumption, arterial pressure, lactate-pyruvate ratio and acid-base homeostasis were observed. Vascular uptake of luminally administered resveratrol was 20.5%. The majority of the absorbed resveratrol was conjugated to yield resveratrol glucuronide (16.8%), which was also the main luminal metabolite (11.2%). Lesser amounts of resveratrol sulfate, 3.0% and 0.3%, were found on the luminal and vascular side, respectively, while only minute amounts of resveratrol and resveratrol conjugates (1.9%) were found in the intestinal tissue. The structures of the resveratrol conjugates were verified by liquid chromatography coupled with mass spectometry (LC-MS). The results demonstrate an ample uptake and metabolic conversion of resveratrol. The proposed perfusion model serves as a tool to evaluate intestinal absorption and metabolic handling of phytochemicals, a pertinent input to the ongoing discussion about their health benefits.
Intramolecular Acylation During Acid Chloride Formation of Some o-Styryl Phenoxyacetic Acids (1991)

Abstract o-Isopropenyl phenoxyactic acids 1 and 8 on treatment with thionyl chloride followed by aqueous workup furnished the acylated products 4 and 9 in moderate yields. The corresponding acid chlorides could also be cyclised with stannic chloride. The acid chlorides from 10 and 11 however did not undergo cyclisation.
WATER-SWELLABLE MATERIALS - APPLICATION IN SELF-HEALING SEALING SYSTEMS (2007)

There is need for sealing applications in numerous fields of technology. Swellable polymers or hydrogels offer the change to develop tailor-made materials for specific sealing tasks. Based on the capability of swelling the materials are able to realise self-healing sealing systems. When getting in contact with aqueous liquids the polymers swell and form hydrogels. The polymers can take up 1000 times of their dry weight, while storing the absorbed liquid in form of a hydrogel even under pressure. The objectives of using these materials are the design of user-oriented sealing solutions, which would provide a high degree of security even where unusual problems are concerned. For the development of sealing products based on swellable polymers, information about the swelling pressure is of essential significance. Up to now only few scientific studies have adressed the application of polymer hydrogels for sealing techniques. Such materials are mostly used empirically. Detailed analyses as well as conclusions regarding mechanisms and interrelations between polymer structure and amount, sealing volume and sealing performance are lacking. In the lecture aspects regarding these interrelations will be outlined. Some applications of self-repairing sealing products will be presented. Based on swellable polymers, sealing products were developed e. g. for sealing the openings in the outside wall of a building the house is conneted to the municipal gas, water, and power supply, sealing joints in the field of civil engineering (sealing granule), or sealing pipe connections of sewage pipes (sealing ring). The present work focuses on the development of selfsealing sewage pipe connections that can be monitored by their swelling pressure. A new generation of selfrepairing sealing material can be realized using swellable thermoplastic-elastomer-composites (Q-TE-C®). Principles of the concepts, results and promising perspectives will be shown. Finally some aspects of biologically inspired reapairing functions (e. g. liana) and ideas for using these functions in combination with hydrogels will be presented.
Time-variant channel estimation using discrete prolate spheroidal sequences (2005)

We propose and analyze a low-complexity channel estimator for a multiuser multicarrier code division multiple access (MC-CDMA) downlink in a time-variant frequency-selective channel. MC-CDMA is based on orthogonal frequency division multiplexing (OFDM). The time-variant channel is estimated individually for every flat-fading subcarrier, assuming small intercarrier interference. The temporal variation of every subcarrier over the duration of a data block is upper bounded by the Doppler bandwidth determined by the maximum velocity of the users. Slepian showed that time-limited snapshots of bandlimited sequences span a low-dimensional subspace. This subspace is also spanned by discrete prolate spheroidal (DPS) sequences. We expand the time-variant subcarrier coefficients in terms of orthogonal DPS sequences we call Slepian basis expansion. This enables a time-variant channel description that avoids the frequency leakage effect of the Fourier basis expansion. The square bias of the Slepian basis expansion per subcarrier is three magnitudes smaller than the square bias of the Fourier basis expansion. We show simulation results for a fully loaded MC-CDMA downlink with classic linear minimum mean square error multiuser detection. The users are moving with 19.4 m/s. Using the Slepian basis expansion channel estimator and a pilot ratio of only 2%, we achieve a bit error rate performance as with perfect channel knowledge.
Improved Techniques for Assessment of Serum Lipoprotein Patterns. II. Rapid Method for Diagnosis of Type III Hyperlipoproteinemia without Ultracentrifugation (1973)

Abstract Based on the previously described technique [Clin. Chem.19, 737 (1973)] of precipitating plasma lipoproteins with polyanions after their electrophoretic separation in gels, a new method is presented for diagnosing type III hyperlipoproteinemia without need for ultracentrifugation or immunologic techniques. Used in the procedure are 0.1 mol/liter MgCl2, 1.5 g/liter heparin, and 10 g/liter NaCl to visualize selectively the very-low-density lipoproteins in agarose gel after electrophoresis. The technique is simple, inexpensive, accessible to every laboratory, and provides the answer in less than 2 h after electrophoresis of the patient’s whole serum. The results obtained are the same as those obtained by ultracentrifugation followed by lipoprotein electrophoresis of the isolated fractions.
RADIATION AND RECEIVER PATTERN OF SHEAR AND COMPRESSIONAL WAVES AS A FUNCTION OF POISSON'S RATIO* (1983)

A bstract Shear (= S) wave studies in addition to compressional (= P) wave surveys have revealed that S‐wave velocities are much more variable than P‐wave velocities. This strongly affects Poisson's ratio σ, especially in young sediments. It is shown that σ has a great influence on the directivity pattern, i.e., on the radiation and receiving characteristic of horizontal sources and receivers. For their calculation, well‐known surface boundary conditions and White's statement of the reciprocity relation (White 1965) are used. They also form the basis for the combination of source and receiver patterns essential for practical field work. The various combinations of horizontally and vertically arranged sources and receivers are investigated with regard to their directivity pattern, their amplitude ratio and, in general, to their usefulness in seismic prospecting.
ChemInform Abstract: SILICON IN SYNTHESIS. C2‐C3 ANNULATION USING VINYLTRIMETHYLSILANE AS AN ETHYLENE EQUIVALENT FOR BICYCLO(N.3.0)ENONE SYNTHESIS (1979)

Abstract Cycloalkenyl‐carbonsäurechloride (I) reagieren mit Zinntetrachlorid und Trimethylvinylsilan zu den kondensierten Cyclopentenonen (II).