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exploring the mass gap:Black holes in green pea galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 170-171页

作者： James e.Rhoads School of earth and Space exploration Arizona State UniversityTempeAZ 85287USA

We know about black holes primarily on two mass scales(e.g.,see Figure 22 of ref.[1]).Supermassive black holes inhabit the centers of galaxies,where they sometimes power active galactic nuclei(AGN).Their populations can be probed through AGN surveys,tidal disruption event surveys,and(in the closest galaxies)stellar and gas dynamics in the innermost regions where the black hole dominates the gravitational potential.

关键词： galaxies tidal galactic

Learning the optimal power flow:environment design matters

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energy and AI 2024年第3期17卷 432-443页

作者： Thomas Wolgast Astrid Nieße Carl von Ossietzky Universität Oldenburg Department of Computing ScienceDigitalized Energy SystemsAmmerländer Heerstraße 114-118Oldenburg26129Germany

To solve the optimal power flow(OPF)problem,reinforcement learning(RL)emerges as a promising new ***,the RL-OPF literature is strongly divided regarding the exact formulation of the OPF problem as an RL *** this work,we collect and implement diverse environment design decisions from the literature regarding training data,observation space,episode definition,and reward function *** an experimental analysis,we show the significant impact of these environment design options on RL-OPF training ***,we derive some first recommendations regarding the choice of these design *** created environment framework is fully open-source and can serve as a benchmark for future research in the RL-OPF field.

关键词： Reinforcement learning Optimal power flow environment design economic Dispatch Voltage control Reactive power market

Manifold learning of four-dimensional scanning transmission electron microscopy

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npj Computational Materials 2019年第1期5卷 1097-1104页

作者： Xin Li ondrej.e.dyck Mark P.Oxley Andrew R.Lupini Leland McInnes John Healy Stephen Jesse Sergei V.Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTN 37831USA Tutte Institute for Mathematics and Computing OttawaCanada

Four-dimensional scanning transmission electron microscopy(4D-STeM)of local atomic diffraction patterns is emerging as a powerful technique for probing intricate details of atomic structure and atomic electric ***,efficient processing and interpretation of large volumes of data remain challenging,especially for two-dimensional or light materials because the diffraction signal recorded on the pixelated arrays is *** we employ data-driven manifold leaning approaches for straightforward visualization and exploration analysis of 4D-STeM datasets,distilling real-space neighboring effects on atomically resolved deflection patterns from single-layer graphene,with single dopant atoms,as recorded on a pixelated *** extracted patterns relate to both individual atom sites and sublattice structures,effectively discriminating single dopant anomalies via multimode *** believe manifold learning analysis will accelerate physics discoveries coupled between data-rich imaging mechanisms and materials such as ferroelectric,topological spin,and van der Waals heterostructures.

关键词： manifold straight details

Integrated Zoology calls for papers:special issue on wildlife diseases and parasitology

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Integrative Zoology 2024年第3期19卷 424-425页

作者： Nubia e.MATTA Wenhua XIONG Department of Biology Universidad Nacional de ColombiaBogotaColombia International Society of Zoological Sciences BeijingChina Institute of Zoology Chinese Academy of SciencesBeijingChina

The VI International Conference on Malaria and Other Blood Parasites of Wildlife and the III International Symposium of the Wildlife Diseases Research Network are scheduled to be held in Medellín,Colombia,from November 26 to 30 of 2024(https://***/lLW79).It will be hosted by the University of Antioquia’s Department of Biology and the Universidad Nacional de Colombia Department of Biology.

关键词： Blood Malaria diseases

Optimization of Random Feature Method in the High-Precision Regime

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1490-1517页

作者： Jingrun Chen Weinan e Yifei Sun School of Mathematical Sciences and Suzhou Institute for Advanced Research Suzhou 215006JiangsuChina University of Science and Technology of China Hefei 230026AnhuiChina Center for Machine Learning Research and School of Mathematical Sciences Peking UniversityBeijing 100871China AI for Science Institute Beijing 100084China School of Mathematical Sciences Soochow UniversitySuzhou 215006JiangsuChina

Machine learning has been widely used for solving partial differential equations(PDes)in recent years,among which the random feature method(RFM)exhibits spectral accuracy and can compete with traditional solvers in terms of both accuracy and ***,the optimization problem in the RFM is more difficult to solve than those that arise in traditional *** the broader machine-learning research,which frequently targets tasks within the low-precision regime,our study focuses on the high-precision regime crucial for solving *** this work,we study this problem from the following aspects:(i)we analyze the coeffcient matrix that arises in the RFM by studying the distribution of singular values;(ii)we investigate whether the continuous training causes the overfitting issue;(ii)we test direct and iterative methods as well as randomized methods for solving the optimization *** on these results,we find that direct methods are superior to other methods if memory is not an issue,while iterative methods typically have low accuracy and can be improved by preconditioning to some extent.

关键词： Random feature method(RFM) Partial differential equation(PDe) Least-squares problem Direct method Iterative method

Olfactory immune response to SARS-CoV-2

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Cellular & Molecular Immunology 2024年第2期21卷 134-143页

作者： Sebastian A.Wellford e.Ashley Moseman Department of Integrative Immunobiology Duke University School of MedicineDurhamNCUSA

Numerous pathogens can infect the olfactory tract,yet the pandemic caused by SARS-CoV-2 has strongly emphasized the importance of the olfactory mucosa as an immune *** in the nasal passages,the olfactory mucosa is directly exposed to the environment to sense airborne odorants;however,this also means it can serve as a direct route of entry from the outside world into the *** a result,olfactotropic infections can have serious consequences,including dysfunction of the olfactory system,CNS invasion,dissemination to the lower respiratory tract,and transmission between *** research has shown that a distinctive immune response is needed to protect this neuronal and mucosal tissue.A better understanding of innate,adaptive,and structural immune barriers in the olfactory mucosa is needed to develop effective therapeutics and vaccines against olfactotropic microbes such as ***,we summarize the ramifications of SARS-CoV-2 infection of the olfactory mucosa,review the subsequent immune response,and discuss important areas of future research for olfactory immunity to infectious disease.

关键词： Mucosal immunology Neuroimmunology Infectious Disease Sars-CoV-2

Human dental pulp stem/stromal cells in clinical practice

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World Journal of Stem Cells 2024年第2期16卷 54-57页

作者： Mohammed e Grawish Department of Oral Biology Faculty of DentistryMansoura UniversityMansoura 35561Egypt Department of Oral Biology Faculty of Oral and Dental MedicineDelta University for Science and TechnologyMansoura 11152Egypt

Dental pulp stem/stromal cells(DPSCs)are fibroblast-like,neural crest-derived,and multipotent cells that can differentiate into several *** are relatively easy to isolate from healthy and inflamed pulps,with little ethical concerns and can be successfully cryopreserved and *** therapeutic effects of DPSCs derived from animal or human sources have been extensively studied through in-vitro and in-vivo animal experiments and the findings indicated that DPSCs are effective not only for dental diseases but also for systemic *** that translational research is a critical step through which the fundamental scientific discoveries could be translated into applicable diagnostics and therapeutics that directly benefit humans,several clinical studies were carried out to generate evidence for the efficacy and safety of autogenous or allogeneic human DPSCs(hDPSCs)as a treatment modality for use in cell-based therapy,regenerative medicine/dentistry and tissue *** clinical medicine,hDPSCs were effective for treating acute ischemic stroke and human exfoliated deciduous teeth-conditioned medium(SHeD-CM)repaired vascular damage of the corpus cavernous,which is the main cause of erectile *** in clinical dentistry,autologous SHeD was able to rege-nerate necrotic dental pulp after implantation into injured teeth,and micrografts enriched with autologous hDPSCs and collagen sponge were considered a treatment option for human intrabony *** contrast,hDPSCs did not add a significant regenerative effect when they were used for the treatment of post-extraction ***-scale clinical studies across diverse populations are still lacking to provide robust evidence on the safety and efficacy of hDPSCs as a new treatment option for various human diseases including dental-related problems.

关键词： Dental pulp stem/stromal cells Human clinical studies Regenerative medicine Regenerative dentistry Cell-based therapy

Formadinium Cation Doping Stabilized Ultra-deep-blue Lead Halide Perovskite Nanocrystal Light-emitting Diodes

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Chemical Research in Chinese Universities 2024年第3期40卷 556-560页

作者： Pui Kei KO Jonathan e.HALPeRT Department of Chemistry The Hong Kong University of Science and TechnologyKowloonHong Kong 999077P.R.China

The halide migration effect in mixed-halide lead-based perovskite is a serious problem hindering the development of its display *** this study,we have successfully addressed this issue by reporting formadinium(FA)doped mixed-halide perovskite nanocrystals(NCs)with ultra-deep-blue emission of 450 nm,narrow bandwidth of 16 nm,and a high photoluminescence quantum yield(PLQY)of 66%.The perovskite nanocrystal light-emitting diodes(NC-LeDs)using this nanocrystal as an active layer achieved a maximum external quantum efficiency(eQe)of 0.32%,30-fold improved compared to that of pristine and stable electroluminescence(eL)spectra at 450 nm under a 4.9–8.0 V *** findings demonstrate the potential of our approach in developing stable and efficient deep blue perovskite NC-LeDs.

关键词： Halide perovskite Light-emitting diode Deep-blue

Chirality enables thermal magnon transistors

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 161-166页

作者： Tao Yu Chengyuan Cai Gerrit e.W.Bauer School of Physics Huazhong University of Science and TechnologyWuhan 430074China .WPI-AIMR and Institute for Materials Research and SCIS Tohoku UniversitySendai 980-8577Japan Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China

We report a theory of thermal spin pumping into proximity magnets under a transverse-bias-driven heat flow of magnons in magnetic films when the dipolar coupling to the magnetic gate is tuned to be “chiral”. While there is no rectification of the magnon current in the film, we predict that chirality diverts a large percentage(50% for perfect chirality) of it into the gate. This transverse thermal spin pumping effect can be controlled by rotating the film magnetization and may help manage the heat flow in future magnonic circuits.

关键词： magnon chirality quantum transport transistor