104 results match your criteria 3 h persistence

Synthesis of 1-indolyl-3,5,8-substituted γ-carbolines: one-pot solvent-free protocol and biological evaluation.

Beilstein J Org Chem 2021 17;17:1453-1463. Epub 2021 Jun 17.

Department of Chemistry, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore-453 552, India.

1,5Disubstituted indole-2-carboxaldehyde derivatives - and glycine alkyl esters - are shown to undergo a novel cascade imination-heterocylization in the presence of the organic base DIPEA to provide 1-indolyl-3,5,8-substituted γ-carbolines - in good yields. The γ-carbolines are fluorescent and exhibit anticancer activities against cervical, lung, breast, skin, and kidney cancer cells. Read More

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Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run.

Phys Rev Lett 2021 Jun;126(24):241102

SUPA, University of Strathclyde, Glasgow G1 1XQ, United Kingdom.

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. Read More

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Synthesis of biologically active fused 1,4-oxathiin derivatives from 4-hydroxydithiocoumarins, arylacetylenes and dimethyl sulfoxide by Cu(i)-catalyzed C-H functionalization and cross-dehydrogenative C-S coupling reactions.

Org Biomol Chem 2021 Jul 11;19(26):5818-5826. Epub 2021 Jun 11.

Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.

The hitherto unreported 2-aryl-10H-thiochromeno[3,2-b][1,4]oxathiin-10-one derivatives are obtained in a single pot from 4-hydroxydithiocoumarins, arylacetylenes and dimethyl sulfoxide in the presence of 10 mol% CuI and KCO in an oil bath at 70 °C. The novelties of the present protocol are (i) selective C-H functionalization at the C-3 position of 4-hydroxydithiocoumarin, (ii) regioselective hydrothiolation with arylacetylenes and (iii) concomitant cyclisation. The major advantages are mild reaction conditions, broad substrate scope and good yield. Read More

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Crystalline Interlayers for Reducing the Effective Thermal Boundary Resistance in GaN-on-Diamond.

ACS Appl Mater Interfaces 2020 Nov 16. Epub 2020 Nov 16.

Centre for Device Thermography and Reliability, H.H. Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL, U.K.

Integrating diamond with GaN high electron mobility transistors (HEMTs) improves thermal management, ultimately increasing the reliability and performance of high-power high-frequency radio frequency amplifiers. Conventionally, an amorphous interlayer is used before growing polycrystalline diamond onto GaN in these devices. This layer contributes significantly to the effective thermal boundary resistance (TBR) between the GaN HEMT and the diamond, reducing the benefit of the diamond heat spreader. Read More

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November 2020

GW190521: A Binary Black Hole Merger with a Total Mass of 150  M_{⊙}.

Phys Rev Lett 2020 Sep;125(10):101102

LIGO, California Institute of Technology, Pasadena, California 91125, USA.

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21}  M_{⊙} and 66_{-18}^{+17}  M_{⊙} (90% credible intervals). Read More

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September 2020

4-Methylumbelliferone fused oxazole thioether derivatives: synthesis, characterization and antifungal activities.

Nat Prod Res 2020 Aug 6:1-7. Epub 2020 Aug 6.

Research Center of Agro-bionic Engineering & Technology of Shandong Province, College of Chemistry & Pharm, Qingdao Agricultural University, Qingdao, China.

Series of thioether derivatives containing 4-methylumbelliferone fused oxazole moiety were designed and synthesised, their structures were fully characterized by H NMR, C NMR and HR-ESI-MS as well. Moreover, the antifungal potency of the title compounds were preliminarily evaluated for their possible use as a fungicide. Meanwhile, ethyl thioethers and displayed remarkable inhibitory effect against the mycelium growth of and with EC of 12-16 μg/mL. Read More

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Preparation and evaluation of zeolites for ammonium removal from municipal wastewater through ion exchange process.

Sci Rep 2020 07 24;10(1):12426. Epub 2020 Jul 24.

School of Water Sciences, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK.

The application of ion exchange process for ammonium (NH-N) removal from wastewater is limited due to the lack of suppliers of engineered zeolites which present high ammonium exchange capacity (AEC) and mechanical strength. This study focuses on the preparation and evaluation of synthetic zeolites (Zeolite1-6) by measuring AEC and resistance to attrition and compression, against natural (clinoptilolite) and engineered zeolite (reference, Zeolite-N). At high NH-N concentrations, Zeolite6 and Zeolite2 showed capacities of 4. Read More

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Targeting STAT3 anti-apoptosis pathways with organic and hybrid organic-inorganic inhibitors.

Org Biomol Chem 2020 05;18(17):3288-3296

Department of Chemistry, Rice University, Houston, TX 77005, USA.

Recurrence and drug resistance are major challenges in the treatment of acute myeloid leukemia (AML) that spur efforts to identify new clinical targets and active agents. STAT3 has emerged as a potential target in resistant AML, but inhibiting STAT3 function has proven challenging. This paper describes synthetic studies and biological assays for a naphthalene sulfonamide inhibitor class of molecules that inhibit G-CSF-induced STAT3 phosphorylation in cellulo and induce apoptosis in AML cells. Read More

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Extreme Fermi Surface Smearing in a Maximally Disordered Concentrated Solid Solution.

Phys Rev Lett 2020 Jan;124(4):046402

H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, United Kingdom.

We show that the Fermi surface can survive the presence of extreme compositional disorder in the equiatomic alloy Ni_{0.25}Fe_{0.25}Co_{0. Read More

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January 2020

Adaptation and Evaluation of Myfood24-Germany: A Web-Based Self-Administered 24-h Dietary Recall for the German Adult Population.

Nutrients 2020 Jan 6;12(1). Epub 2020 Jan 6.

Nutritional Epidemiology, Department of Nutrition and Food Sciences, University of Bonn, 53115 Bonn, North Rhine-Westphalia, Germany.

Our aim was to develop and evaluate a German adaptation of myfood24, a fully automated, web-based 24-h dietary recall (24HDR). To complete a self-administered 24HDR with myfood24, users have to search and enter consumed foods within the underlying database by a free text search. The adaptation process thus mainly consisted of the development of an appropriate food database. Read More

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January 2020

Polygenic risk for Alzheimer's disease shapes hippocampal scene-selectivity.

Neuropsychopharmacology 2020 06 2;45(7):1171-1178. Epub 2020 Jan 2.

Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, CF24 4HQ, UK.

Preclinical models of Alzheimer's disease (AD) suggest APOE modulates brain function in structures vulnerable to AD pathophysiology. However, genome-wide association studies now demonstrate that AD risk is shaped by a broader polygenic architecture, estimated via polygenic risk scoring (AD-PRS). Despite this breakthrough, the effect of AD-PRS on brain function in young individuals remains unknown. Read More

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Wurster Fluidised Bed Coating of Microparticles: Towards Scalable Production of Oral Sustained-Release Liquid Medicines for Patients with Swallowing Difficulties.

AAPS PharmSciTech 2019 Nov 11;21(1). Epub 2019 Nov 11.

Department of Clinical and Pharmaceutical Sciences, University of Hertfordshire, Hatfield, AL10 9AB, UK.

Suspension of microparticles in an easy-to-swallow liquid is one approach to develop sustained-release formulations for children and patients with swallowing difficulties. However, to date production of sustained-release microparticles at the industrial scale has proven to be challenging. The aim of this investigation was to develop an innovative concept in coating sustained-release microparticles using industrial scalable Wurster fluidised bed to produce oral liquid suspensions. Read More

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November 2019

Search for Subsolar Mass Ultracompact Binaries in Advanced LIGO's Second Observing Run.

Phys Rev Lett 2019 Oct;123(16):161102

LIGO, California Institute of Technology, Pasadena, California 91125, USA.

We present a search for subsolar mass ultracompact objects in data obtained during Advanced LIGO's second observing run. In contrast to a previous search of Advanced LIGO data from the first observing run, this search includes the effects of component spin on the gravitational waveform. We identify no viable gravitational-wave candidates consistent with subsolar mass ultracompact binaries with at least one component between 0. Read More

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October 2019

Facile Amine Termination of Nanodiamond Particles and Their Surface Reaction Dynamics.

ACS Omega 2019 Oct 1;4(16):16715-16723. Epub 2019 Oct 1.

Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan.

Nanodiamond synthesized by the detonation method is a composite of sp/sp carbon structures; amorphous and disordered-sp carbons populate the surface of a sp diamond core lattice. Because of the production process, various elemental impurities such as N, O, H, and so forth are inherent in interstitial sites or the surface carbon (sp/amorphous) network. Herein, the reaction dynamics on the surface of ultradisperse diamond (UDD) due to the surface transformation or reconstruction during annealing in vacuum with temperatures ranging from ambient to 800 °C is described. Read More

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October 2019

Molecular interaction balanced one- and two-dimensional hybrid nanoarchitectures for high-performance supercapacitors.

Phys Chem Chem Phys 2019 Oct 7;21(40):22283-22292. Epub 2019 Oct 7.

Engineering Department, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, UK.

Hybridisation of one-dimensional (1D) and two-dimensional (2D) materials to enhance charge storage has received considerable attention, but a fundamental understanding of the inherent ratio-dependent charge transfer mechanisms associated with the modulation of their molecular interactions is still within the community. Herein, we examined 1D surface oxidised carbon nanotubes (Ox-CNTs) and 2D reduced graphene oxide (rGO) to understand their ratio-dependent charge transfer and molecular interaction dynamics. We found that stepwise ultrasonication and the self-assembly process can control the thermodynamic molecular interactions, which result in rGO and Ox-CNT suspensions not only well dispersed in N,N-dimethylformamide but also self-organised into sandwiched nanoarchitectures. Read More

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October 2019

Tests of General Relativity with GW170817.

Phys Rev Lett 2019 Jul;123(1):011102

LAL, Univ. Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, F-91898 Orsay, France.

The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Read More

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Observation of a superconducting glass state in granular superconducting diamond.

Sci Rep 2019 Mar 14;9(1):4578. Epub 2019 Mar 14.

School of Physics and Astronomy, Cardiff University, Queen's Buildings, The Parade, Cardiff, CF24 3AA, UK.

The magnetic field dependence of the superconductivity in nanocrystalline boron doped diamond thin films is reported. Evidence of a superconducting glass state is presented, as demonstrated by the observation of a quasi de Almeida-Thouless line in the phase diagram and a logarithmic time dependence of the magnetism. The position of the phase boundary in the H-T plane is determined from electrical transport data by detailed fitting to quasi-zero-dimensional fluctuation conductivity theory. Read More

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Constraining the p-Mode-g-Mode Tidal Instability with GW170817.

Phys Rev Lett 2019 Feb;122(6):061104

LAL, University Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, F-91898 Orsay, France.

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Read More

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February 2019

Coherence and Density Dynamics of Excitons in a Single-Layer MoS Reaching the Homogeneous Limit.

ACS Nano 2019 Mar 20;13(3):3500-3511. Epub 2019 Feb 20.

University Grenoble Alpes, CNRS, Grenoble INP , Institut Néel , 38000 Grenoble , France.

We measure the coherent nonlinear response of excitons in a single layer of molybdenum disulfide embedded in hexagonal boron nitride, forming a h-BN/MoS/ h-BN heterostructure. Using four-wave mixing microscopy and imaging, we correlate the exciton inhomogeneous broadening with the homogeneous one and population lifetime. We find that the exciton dynamics is governed by microscopic disorder on top of the ideal crystal properties. Read More

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Room-Temperature Midwavelength Infrared InAsSb Nanowire Photodetector Arrays with AlO Passivation.

Nano Lett 2019 05 28;19(5):2793-2802. Epub 2019 Jan 28.

Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.

Developing uncooled photodetectors at midwavelength infrared (MWIR) is critical for various applications including remote sensing, heat seeking, spectroscopy, and more. In this study, we demonstrate room-temperature operation of nanowire-based photodetectors at MWIR composed of vertical selective-area InAsSb nanowire photoabsorber arrays on large bandgap InP substrate with nanoscale plasmonic gratings. We accomplish this by significantly suppressing the nonradiative recombination at the InAsSb nanowire surfaces by introducing ex situ conformal AlO passivation shells. Read More

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Origins Space Telescope: predictions for far-IR spectroscopic surveys.

Publ Astron Soc Aust 2019 24;36. Epub 2019 Apr 24.

Department of Physics & Astronomy, University of California, Irvine, CA 92697, USA.

We illustrate the extraordinary potential of the (far-IR) Origins Survey Spectrometer (OSS) on board the Origins Space Telescope (OST) to address a variety of open issues on the co-evolution of galaxies and AGNs. We present predictions for blind surveys, each of 1000 h, with different mapped areas (a shallow survey covering an area of 10 deg and a deep survey of 1 deg) and two different concepts of the OST/OSS: with a 5.9m telescope (Concept 2, our reference configuration) and with a 9. Read More

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Search for Subsolar-Mass Ultracompact Binaries in Advanced LIGO's First Observing Run.

Phys Rev Lett 2018 Dec;121(23):231103

LAL, Univ. Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, F-91898 Orsay, France.

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2  M_{⊙}-1.0  M_{⊙} using data taken between September 12, 2015 and January 19, 2016. Read More

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December 2018

InGaAs-GaAs Nanowire Avalanche Photodiodes Toward Single-Photon Detection in Free-Running Mode.

Nano Lett 2019 01 10;19(1):582-590. Epub 2018 Dec 10.

Department of Electrical Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.

Single-photon detection at near-infrared (NIR) wavelengths is critical for light detection and ranging (LiDAR) systems used in imaging technologies such as autonomous vehicle trackers and atmospheric remote sensing. Portable, high-performance LiDAR relies on silicon-based single-photon avalanche diodes (SPADs) because of their extremely low dark count rate (DCR) and afterpulsing probability, but their operation wavelengths are typically limited up to 905 nm. Although InGaAs-InP SPADs offer an alternative platform to extend the operation wavelengths to eye-safe ranges, their high DCR and afterpulsing severely limit their commercial applications. Read More

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January 2019

Uncooled Photodetector at Short-Wavelength Infrared Using InAs Nanowire Photoabsorbers on InP with p- n Heterojunctions.

Nano Lett 2018 12 21;18(12):7901-7908. Epub 2018 Nov 21.

Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.

In this work, we demonstrate an InAs nanowire photodetector at short-wavelength infrared (SWIR) composed of vertically oriented selective-area InAs nanowire photoabsorber arrays on InP substrates, forming InAs-InP heterojunctions. We measure a rectification ratio greater than 300 at room temperature, which indicates a desirable diode performance. The dark current density, normalized to the area of nanowire heterojunctions, is 130 mA/cm at a temperature of 300 K and a reverse bias of 0. Read More

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December 2018

GW170817: Measurements of Neutron Star Radii and Equation of State.

Phys Rev Lett 2018 Oct;121(16):161101

LAL, Univ. Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, F-91898 Orsay, France.

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Read More

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October 2018

Modeling fully coupled hydraulic-mechanical-chemical processes in a natural clay liner under mechanical and chemico-osmotic consolidation.

Environ Sci Pollut Res Int 2018 Dec 25;25(36):36173-36183. Epub 2018 Oct 25.

Key Laboratory of Urban Security & Disaster Engineering, Ministry of Education, Beijing University of Technology, Beijing, 100124, People's Republic of China.

Clayey material that possesses semipermeable membrane property may experience osmotic consolidation in presence of an osmotic gradient. In this paper, a fully coupled H-M-C model has been presented to study solute transport under the combined influence of mechanical and osmotic consolidations and vice versa. The model has been tested against the results of relevant importance and good agreements have been achieved. Read More

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December 2018

A Unified Strategy for the Synthesis of β-Carbolines, γ-Carbolines, and Other Fused Azaheteroaromatics under Mild, Metal-Free Conditions.

Org Lett 2018 10 1;20(20):6336-6339. Epub 2018 Oct 1.

Department of Pharmaceutical Sciences, College of Pharmacy , Union University , Jackson , Tennessee 38305 , United States.

An efficient, unified approach for the synthesis of β-carbolines, γ-carbolines, and other fused azaheteroaromatics has been realized under metal-free conditions, from propargylic amines and (hetero)aromatic aldehydes. This unified strategy provides β- and γ-carbolines as well as a range of fused azaheteroaromatics with a broad substrate scope and excellent functional group compatibility. The formal synthesis of oxopropalines D and G has been achieved on gram scale (3a), in a one-pot reaction from commercially available materials (previous shortest reported route to 3a was 5 steps). Read More

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October 2018

Asymmetric Rh(I)-Catalyzed Functionalization of the 3-C( sp)-H Bond of Benzofuranones with α-Diazoesters.

Org Lett 2018 09 7;20(18):5889-5893. Epub 2018 Sep 7.

School of Chemistry , Sun Yat-Sen University , 135 Xingang West Road , Guangzhou 510275 , China.

An asymmetric Rh(I)-catalyzed functionalization of the 3-C( sp)-H bond of benzofuranones with α-diazoesters has been developed, providing a new strategy for the stereoselective 3-alkylation of benzofuranones. With low catalyst loadings (low to 0.02 mol % Rh), a number of benzofuranones bearing consecutive quaternary and tertiary stereogenic centers have been synthesized (up to 94% yield, 95:5 dr, and >99% ee). Read More

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September 2018

Indirect Reciprocity and the Evolution of Prejudicial Groups.

Sci Rep 2018 09 5;8(1):13247. Epub 2018 Sep 5.

MIT Sloan School of Management, 30 Memorial Dr, Cambridge, MA, 02142, USA.

Prejudicial attitudes are widely seen between human groups, with significant consequences. Actions taken in light of prejudice result in discrimination, and can contribute to societal division and hostile behaviours. We define a new class of group, the prejudicial group, with membership based on a common prejudicial attitude towards the out-group. Read More

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September 2018

Search for Tensor, Vector, and Scalar Polarizations in the Stochastic Gravitational-Wave Background.

Phys Rev Lett 2018 May;120(20):201102

LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, F-91898 Orsay, France.

The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Read More

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