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Let a := (a1,..., an). [1,8) n, p := (p1,..., pn). (0,8) n and H p a (Rn) be the anisotropic mixed-norm Hardy space associated with a defined via the non-tangential grand maximal function. In this article, via first establishing a...
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Let a := (a1,..., an). [1,8) n, p := (p1,..., pn). (0,8) n and H p a (Rn) be the anisotropic mixed-norm Hardy space associated with a defined via the non-tangential grand maximal function. In this article, via first establishing a Calderon-Zygmund decomposition and a discrete Calderon reproducing formula, the authors then characterize H p a (Rn), respectively, by means of atoms, the Lusin area function, the Littlewood-Paley g-function or g *. -function. The obtained Littlewood-Paley g-function characterization of H p a (Rn) coincidentally confirms a conjecture proposed by Hart et al. (TransAmMath Soc, https://doi. org/10.1090/tran/7312, 2017). Applying the aforementioned Calderon-Zygmund decomposition as well as the atomic characterization of H p a (Rn), the authors establish a finite atomic characterization of H p a (Rn), which further induces a criterion on the boundedness of sublinear operators from H p a (Rn) into a quasi-Banach space. Then, applying this criterion, the authors obtain the boundedness of anisotropic Calderon-Zygmund operators from H p a (Rn) to itself [or to the mixed-norm Lebesgue space L p(Rn)]. The obtained atomic characterizations of H p a (Rn) and boundedness of anisotropic Calderon-Zygmund operators on these Hardy-type spaces positively answer two questions mentioned by Cleanthous et al. (J Geom Anal 27: 2758-2787, 2017). All these results are new even for the isotropic mixed-norm Hardy spaces on R-n.
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Fibers, originating from nature and mastered by human, have woven their way throughout the entire history of human civilization. Recent developments in semiconducting polymer materials have further endowed fibers and textiles with...
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Fibers, originating from nature and mastered by human, have woven their way throughout the entire history of human civilization. Recent developments in semiconducting polymer materials have further endowed fibers and textiles with various electronic functions, which are attractive in applications such as information interfacing, personalized medicine, and clean energy. Owing to their ability to be easily integrated into daily life, soft fiber electronics based on semiconducting polymers have gained popularity recently for wearable and implantable applications. Herein, we present a review of the previous and current progress in semiconducting polymer-based fiber electronics, particularly focusing on smart-wearable and implantable areas. First, we provide a brief overview of semiconducting polymers from the viewpoint of materials based on the basic concepts and functionality requirements of different devices. Then we analyze the existing applications and associated devices such as information interfaces, healthcare and medicine, and energy conversion and storage. The working principle and performance of semiconducting polymer-based fiber devices are summarized. Furthermore, we focus on the fabrication techniques of fiber devices. Based on the continuous fabrication of one-dimensional fiber and yarn, we introduce two-and three-dimensional fabric fabricating methods. Finally, we review challenges and relevant perspectives and potential solutions to address the related problems.
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Diarylethene (DAE) photoswitch is a new and promising family of photochromic molecules and has shown superior performance as a smart trigger in stimulus-responsive materials. During the past few decades, the DAE family has achieve...
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Diarylethene (DAE) photoswitch is a new and promising family of photochromic molecules and has shown superior performance as a smart trigger in stimulus-responsive materials. During the past few decades, the DAE family has achieved a leap from simple molecules to functional molecules and developed toward validity as a universal switching building block. In recent years, the introduction of DAE into an assembly system has been an attractive strategy that enables the photochromic behavior of the building blocks to be manifested at the level of the entire system, beyond the DAE unit itself. This assembly-based strategy will bring many unexpected results that promote the design and manufacture of a new generation of advanced materials. Here, recent advances in the design and fabrication of diarylethene as a trigger in materials science, chemistry, and biomedicine are reviewed.
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We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign, which was conducted in 2017 April i...
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We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign, which was conducted in 2017 April in the lambda 3 mm and lambda 1.3 mm bands, in concert with the Global mm-VLBI Array (GMVA) and the Event Horizon Telescope (EHT), respectively. We determine the polarization and Faraday properties of all VLBI targets, including Sgr A*, M87, and a dozen radio-loud active galactic nuclei (AGNs), in the two bands at several epochs in a time window of 10 days. We detect high linear polarization fractions (2%-15%) and large rotation measures (RM > 10(3.3)-10(5.5) rad m(-2)), confirming the trends of previous AGN studies at millimeter wavelengths. We find that blazars are more strongly polarized than other AGNs in the sample, while exhibiting (on average) order-of-magnitude lower RM values, consistent with the AGN viewing angle unification scheme. For Sgr A* we report a mean RM of (-4.2 0.3) x 10(5) rad m(-2) at 1.3 mm, consistent with measurements over the past decade and, for the first time, an RM of (-2.1 0.1) x 10(5) rad m(-2) at 3 mm, suggesting that about half of the Faraday rotation at 1.3 mm may occur between the 3 mm photosphere and the 1.3 mm source. We also report the first unambiguous measurement of RM toward the M87 nucleus at millimeter wavelengths, which undergoes significant changes in magnitude and sign reversals on a one year timescale, spanning the range from -1.2 to 0.3 x 10(5) rad m(-2) at 3 mm and -4.1 to 1.5 x 10(5) rad m(-2) at 1.3 mm. Given this time variability, we argue that, unlike the case of Sgr A*, the RM in M87 does not provide an accurate estimate of the mass accretion rate onto the black hole. We put forward a two-component model, comprised of a variable compact region and a static extended region, that can simultaneously explain the polarimetric properties observed by both the EHT (on horizon scales) and ALMA (which observes the combined emission from both components). These measurements provide critical constraints for the calibration, analysis, and interpretation of simultaneously obtained VLBI data with the EHT and GMVA.
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Let (p)over-right-arrow is an element of (0, infinity)(n) and A be a general expansive matrix on R-n. In this article, via the non-tangential grand maximal function, the authors first introduce the anisotropic mixed-norm Hardy spa...
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Let (p)over-right-arrow is an element of (0, infinity)(n) and A be a general expansive matrix on R-n. In this article, via the non-tangential grand maximal function, the authors first introduce the anisotropic mixed-norm Hardy spaces H-A((p)over-right-arrow)(R-n) associated with A and then establish their radial or non-tangential maximal function characterizations. Moreover, the authors characterize H-A((p)over-right-arrow)(R-n), respectively, by means of atoms, finite atoms, Lusin area functions, Littlewood-Paley g-functions or g(lambda)*-functions via first establishing an anisotropic Fefferman-Stein vector-valued inequality on the mixed-norm Lebesgue space L(p)over-right-arrow(R-n) . In addition, the authors also obtain the duality between H-A((p)over-right-arrow)(R-n) and the anisotropic mixed-norm Campanato spaces. As applications, the authors establish a criterion on the boundedness of sublinear operators from H-A((p)over-right-arrow)(R-n) into a quasi-Banach space. Applying this criterion, the authors then obtain the boundedness of anisotropic convolutional delta-type and non-convolutional beta-order Calderon-Zygmund operators from H-A((p)over-right-arrow)(R-n) to itself [or to L(p)over-right-arrow(R-n)]. As a corollary, the boundedness of anisotropic convolutional delta-type Calderon-Zygmund operators on the mixed-norm Lebesgue space L(p)over-right-arrow(R-n) with (p)over-right-arrow is an element of (1, infinity)(n) is also presented.
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Let p(.) : R-n -> (0, infinity] be a variable exponent function satisfying the globally log-Holder continuous condition, q is an element of (0, infinity] and A be a general expansive matrix on R-n. Let H-A(p(.),q) (R-n) be the ani...
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Let p(.) : R-n -> (0, infinity] be a variable exponent function satisfying the globally log-Holder continuous condition, q is an element of (0, infinity] and A be a general expansive matrix on R-n. Let H-A(p(.),q) (R-n) be the anisotropic variable Hardy-Lorentz space associated with A defined via the radial grand maximal function. In this article, the authors characterize H-A(p(.),q) (R-n) by means of the Littlewood-Paley g-function or the Littlewood-Paley g(lambda)*-function via first establishing an anisotropic Fefferman-Stein vector-valued inequality on the variable Lorentz space L-p(.),L-q (R-n). Moreover, the finite atomic characterization of H-A(p(.),q) (R-n) is also obtained. As applications, the authors then establish a criterion on the boundedness of sublinear operators from H-A(p(.),q) (R-n) into a quasi-Banach space. Applying this criterion, the authors show that the maximal operators of the Bochner-Riesz and the Weierstrass means are bounded from H-A(p(.),q) (R-n) to L-A(p(.),q) (R-n) and, as consequences, some almost everywhere and norm convergences of these Bochner-Riesz andWeierstrass means are also obtained. These results on the Bochner-Riesz and the Weierstrass means are new even in the isotropic case.
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In 2017 April, the Event Horizon Telescope (EHT) observed the near-horizon region around the supermassive black hole at the core of the M87 galaxy. These 1.3 mm wavelength observations revealed a compact asymmetric ring-like sourc...
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In 2017 April, the Event Horizon Telescope (EHT) observed the near-horizon region around the supermassive black hole at the core of the M87 galaxy. These 1.3 mm wavelength observations revealed a compact asymmetric ring-like source morphology. This structure originates from synchrotron emission produced by relativistic plasma located in the immediate vicinity of the black hole. Here we present the corresponding linear-polarimetric EHT images of the center of M87. We find that only a part of the ring is significantly polarized. The resolved fractional linear polarization has a maximum located in the southwest part of the ring, where it rises to the level of similar to 15%. The polarization position angles are arranged in a nearly azimuthal pattern. We perform quantitative measurements of relevant polarimetric properties of the compact emission and find evidence for the temporal evolution of the polarized source structure over one week of EHT observations. The details of the polarimetric data reduction and calibration methodology are provided. We carry out the data analysis using multiple independent imaging and modeling techniques, each of which is validated against a suite of synthetic data sets. The gross polarimetric structure and its apparent evolution with time are insensitive to the method used to reconstruct the image. These polarimetric images carry information about the structure of the magnetic fields responsible for the synchrotron emission. Their physical interpretation is discussed in an accompanying publication.
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This paper studies implications of return extrapolation in a consumption-based asset pricing model. We show that return extrapolation has strong implications for the pricing kernel. The time variation in the agen-t's return expect...
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This paper studies implications of return extrapolation in a consumption-based asset pricing model. We show that return extrapolation has strong implications for the pricing kernel. The time variation in the agen-t's return expectations is mainly reflected in the short rate and little in return volatility and equity premium. Return extrapolation causes return volatility and equity premium to be lower than the rational counter-parts. In addition to the risk premium, the equity premium can include a sentiment premium that is due to dividend expectation bias rather than return extrapolation bias. Thus, time-varying dividend (rather than re-turn) expectation bias helps produce a volatile equity premium. These results show that return extrapolation exacerbates asset pricing puzzles and fundamental extrapolation helps resolve puzzles. Crown Copyright (c) 2023 Published by Elsevier Inc. All rights reserved.
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Let p(.) : R-n -> (0, infinity] be a variable exponent function satisfying the globally log-Holder continuous condition and A a general expansive matrix on R-n. In this article, the authors first introduce the variable anisotropic...
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Let p(.) : R-n -> (0, infinity] be a variable exponent function satisfying the globally log-Holder continuous condition and A a general expansive matrix on R-n. In this article, the authors first introduce the variable anisotropic Hardy space H-A(p(.))(R-n) associated with A, via the non-tangential grand maximal function, and then establish its radial or non-tangential maximal function characterizations. Moreover, the authors also obtain various equivalent characterizations of H-A(p(.))(R-n), respectively, by means of atoms, finite atoms, the Lusin area function, the Littlewood-Paley g-function or g(lambda)*-function. As applications, the authors first establish a criterion on the boundedness of sublinear operators from H-A(p(.))(R-n) into a quasi-Banach space. Then, applying this criterion, the authors show that the maximal operators of the Bochner-Riesz and the Weierstrass means are bounded from H-A(p(.))(R-n) to L-p(.)(R-n) and, as consequences, some almost everywhere and norm convergences of these Bochner-Riesz and Weierstrass means are also obtained. These results on the Bochner-Riesz and the Weierstrass means are new even in the isotropic case.
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Event Horizon Telescope (EHT) observations at 230 GHz have now imaged polarized emission around the supermassive black hole in M87 on event-horizon scales. This polarized synchrotron radiation probes the structure of magnetic fiel...
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Event Horizon Telescope (EHT) observations at 230 GHz have now imaged polarized emission around the supermassive black hole in M87 on event-horizon scales. This polarized synchrotron radiation probes the structure of magnetic fields and the plasma properties near the black hole. Here we compare the resolved polarization structure observed by the EHT, along with simultaneous unresolved observations with the Atacama Large Millimeter/submillimeter Array, to expectations from theoretical models. The low fractional linear polarization in the resolved image suggests that the polarization is scrambled on scales smaller than the EHT beam, which we attribute to Faraday rotation internal to the emission region. We estimate the average density n(e) similar to 10(4-7) cm(-3), magnetic field strength B similar to 1-30 G, and electron temperature T-e similar to (1-12) x 10(10) K of the radiating plasma in a simple one-zone emission model. We show that the net azimuthal linear polarization pattern may result from organized, poloidal magnetic fields in the emission region. In a quantitative comparison with a large library of simulated polarimetric images from general relativistic magnetohydrodynamic (GRMHD) simulations, we identify a subset of physical models that can explain critical features of the polarimetric EHT observations while producing a relativistic jet of sufficient power. The consistent GRMHD models are all of magnetically arrested accretion disks, where near-horizon magnetic fields are dynamically important. We use the models to infer a mass accretion rate onto the black hole in M87 of (3-20) x 10(-4) M yr(-1).
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