Perovskite quantum dots (QDs) have been hotly pursued in recent decades owing to their quantum confinement effect and defect-tolerant nature. Their unique optical properties, such as high ...photoluminescence quantum yield (PLQY) approaching unity, narrow emission bandwidth, tunable wavelength spanning the entire visible spectrum, and compatibility with flexible/stretchable electronics, render perovskite QDs promising for next-generation solid lighting sources and information displays. Herein, the advances in perovskite QDs and their applications in LEDs are reviewed. Strategies to fabricate efficient perovskite QDs and device configuration, including material composition design, synthetic methods, surface engineering, and device optimization, are investigated and highlighted. Moreover, the main challenges in perovskite QDs of instability and toxicity (lead-based) are identified, while the solutions undertaken with respect to composition engineering, device encapsulation, and lead-replacement QDs are demonstrated. Meanwhile, perspectives for the further development of perovskite QDs and corresponding LEDs are presented.
Perovskite QDs are promising platforms for light-emitting applications. Advances in perovskite QDs, including optoelectronic properties and device performance are discussed.
The ability to detect, respond and adapt to mitochondrial stress ensures the development and survival of organisms. Caenorhabditis elegans responds to mitochondrial stress by activating the ...mitochondrial unfolded protein response (UPR
) to buffer the mitochondrial folding environment, rewire the metabolic state, and promote innate immunity and lifespan extension. Here we show that HDA-1, the C. elegans ortholog of mammalian histone deacetylase (HDAC) is required for mitochondrial stress-mediated activation of UPR
. HDA-1 interacts and coordinates with the genome organizer DVE-1 to induce the transcription of a broad spectrum of UPR
, innate immune response and metabolic reprogramming genes. In rhesus monkey and human tissues, HDAC1/2 transcript levels correlate with the expression of UPR
genes. Knocking down or pharmacological inhibition of HDAC1/2 disrupts the activation of the UPR
and the mitochondrial network in mammalian cells. Our results underscore an evolutionarily conserved mechanism of HDAC1/2 in modulating mitochondrial homeostasis and regulating longevity.
Perspectives on pain in Down syndrome Shaikh, Ammara; Li, Yun‐Qing; Lu, Jie
Medicinal research reviews,
September 2023, 2023-Sep, 2023-09-00, 20230901, Volume:
43, Issue:
5
Journal Article
Peer reviewed
Down syndrome (DS) or trisomy 21 is a genetic condition often accompanied by chronic pain caused by congenital abnormalities and/or conditions, such as osteoarthritis, recurrent infections, and ...leukemia. Although DS patients are more susceptible to chronic pain as compared to the general population, the pain experience in these individuals may vary, attributed to the heterogenous structural and functional differences in the central nervous system, which might result in abnormal pain sensory information transduction, transmission, modulation, and perception. We tried to elaborate on some key questions and possible explanations in this review. Further clarification of the mechanisms underlying such abnormal conditions induced by the structural and functional differences is needed to help pain management in DS patients.
Feature selection is one of the key problems for machine learning and data mining. In this review paper, a brief historical background of the field is given, followed by a selection of challenges ...which are of particular current interests, such as feature selection for high-dimensional small sample size data, large-scale data, and secure feature selection. Along with these challenges, some hot topics for feature selection have emerged, e.g., stable feature selection, multi-view feature selection, distributed feature selection, multi-label feature selection, online feature selection, and adversarial feature selection. Then, the recent advances of these topics are surveyed in this paper. For each topic, the existing problems are analyzed, and then, current solutions to these problems are presented and discussed. Besides the topics, some representative applications of feature selection are also introduced, such as applications in bioinformatics, social media, and multimedia retrieval.
Spatially resolved (sub)millimeter polarization has been detected by Atacama Large Millimeter/submillimeter Array in an increasing number of disks. The majority of the observations show polarization ...patterns consistent with self scattering, especially at Band 7. The inferred sizes of the grains are typically of order 100 m, which is very different from the millimeter size commonly inferred from the dust opacity index β. In an effort to resolve this discrepancy, we first introduce the so-called "Coplanar Isotropic Radiation Field" approximation, which enables the computation of the (signed) polarization fraction semianalytically. With an oft-adopted dust composition, we find that models with big dust grains produce very small polarization with reversed orientation, which has not been observed. The semianalytic results are validated through Monte Carlo radiative transfer simulations. In these models, the "correct" polarization orientation and the small β index are mutually exclusive. To resolve this tension, we explore a wide range of dust models, parameterized by their complex refractive indices m = n + ik. We find that both the fraction and the orientation of the polarization depend on the refractive index in a complex way, and this dependence is mapped out on an n-k plane for a representative 3 mm size distribution and wavelength of 870 m. In particular, 3 mm-sized refractory organics grains produce reversed polarization, whereas grains made of absorptive carbonaceous materials produce a percent-level, nonreversed polarization; the latter may alleviate the aforementioned tension in grain size estimates. We conclude that scattering-induced polarization has the potential to also probe the grain compositions.
HH 212 is one of the well-studied protostellar systems, showing the first vertically resolved disk with a warm atmosphere around the central protostar. Here we report a detection of nine organic ...molecules (including newly detected ketene, formic acid, deuterated acetonitrile, methyl formate, and ethanol) in the disk atmosphere, confirming that the disk atmosphere is, for HH 212, the chemically rich component, identified before at a lower resolution as a "hot corino." More importantly, we report the first systematic survey and abundance measurement of organic molecules in the disk atmosphere within ∼40 au of the central protostar. The relative abundances of these molecules are similar to those in the hot corinos around other protostars and in Comet Lovejoy. These molecules can be either (i) originally formed on icy grains and then desorbed into gas phase or (ii) quickly formed in the gas phase using simpler species ejected from the dust mantles. The abundances and spatial distributions of the molecules provide strong constraints on models of their formation and transport in star formation. These molecules are expected to form even more complex organic molecules needed for life and deeper observations are needed to find them.
The faithful storage and coherent manipulation of quantum states with matter-systems would enable the realization of large-scale quantum networks based on quantum repeaters. To achieve useful ...communication rates, highly multimode quantum memories are required to construct a multiplexed quantum repeater. Here, we present a demonstration of on-demand storage of orbital-angular-momentum states with weak coherent pulses at the single-photon-level in a rare-earth-ion-doped crystal. Through the combination of this spatial degree-of-freedom (DOF) with temporal and spectral degrees of freedom, we create a multiple-DOF memory with high multimode capacity. This device can serve as a quantum mode converter with high fidelity, which is a fundamental requirement for the construction of a multiplexed quantum repeater. This device further enables essentially arbitrary spectral and temporal manipulations of spatial-qutrit-encoded photonic pulses in real time. Therefore, the developed quantum memory can serve as a building block for scalable photonic quantum information processing architectures.
This article presents a novel dual-polarized millimeter-wave (mm-Wave) patch antenna with bandpass filtering response. The proposed antenna consists of a differential-fed cross-shaped driven patch ...and four stacked parasitic patches. The combination of the stacked patches and the driven patch can be equivalent to a bandstop filtering circuit for generating a radiation null at the upper band edge. Besides, four additional shorted patches are added beside the cross-shaped driven patch to introduce another radiation null at the lower band edge. Moreover, by embedding a cross-shaped strip between these four stacked patches, the third radiation null is generated to further suppress the upper stopband. As a result, a quasi-elliptic bandpass response is realized without requiring extra filtering circuit. For demonstration, a prototype was fabricated with standard PCB process and measured. The prototype operates in the 5G band (24.25-29.5 GHz) and it has an impedance bandwidth of 20%. The out-of-band gain drops over 15 dB at 23 and 32.5 GHz, respectively, which exhibits high selectivity. These merits make the proposed antenna a good element candidate for the 5G mm-Wave massive MIMO applications to reduce the requirements of the filters in the mm-Wave RF front ends.
Metasurfaces have enabled a plethora of emerging functions within an ultrathin dimension, paving way towards flat and highly integrated photonic devices. Despite the rapid progress in this area, ...simultaneous realization of reconfigurability, high efficiency, and full control over the phase and amplitude of scattered light is posing a great challenge. Here, we try to tackle this challenge by introducing the concept of a reprogrammable hologram based on 1-bit coding metasurfaces. The state of each unit cell of the coding metasurface can be switched between '1' and '0' by electrically controlling the loaded diodes. Our proof-of-concept experiments show that multiple desired holographic images can be realized in real time with only a single coding metasurface. The proposed reprogrammable hologram may be a key in enabling future intelligent devices with reconfigurable and programmable functionalities that may lead to advances in a variety of applications such as microscopy, display, security, data storage, and information processing.Realizing metasurfaces with reconfigurability, high efficiency, and control over phase and amplitude is a challenge. Here, Li et al. introduce a reprogrammable hologram based on a 1-bit coding metasurface, where the state of each unit cell of the coding metasurface can be switched electrically.
Summary
Tea is the world's widely consumed nonalcohol beverage with essential economic and health benefits. Confronted with the increasing large‐scale omics‐data set particularly the genome sequence ...released in tea plant, the construction of a comprehensive knowledgebase is urgently needed to facilitate the utilization of these data sets towards molecular breeding. We hereby present the first integrative and specially designed web‐accessible database, Tea Plant Information Archive (TPIA; http://tpia.teaplant.org). The current release of TPIA employs the comprehensively annotated tea plant genome as framework and incorporates with abundant well‐organized transcriptomes, gene expressions (across species, tissues and stresses), orthologs and characteristic metabolites determining tea quality. It also hosts massive transcription factors, polymorphic simple sequence repeats, single nucleotide polymorphisms, correlations, manually curated functional genes and globally collected germplasm information. A variety of versatile analytic tools (e.g. JBrowse, blast, enrichment analysis, etc.) are established helping users to perform further comparative, evolutionary and functional analysis. We show a case application of TPIA that provides novel and interesting insights into the phytochemical content variation of section Thea of genus Camellia under a well‐resolved phylogenetic framework. The constructed knowledgebase of tea plant will serve as a central gateway for global tea community to better understand the tea plant biology that largely benefits the whole tea industry.
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