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Kagome lattice materials offer a fertile ground to discover novel quantum phases of matter, ranging from unconventional superconductivity and quantum spin liquids to charge orders of various profiles. However, understanding the genuine origin of the quantum phases in kagome materials is often challenging, owing to the intertwined atomic, electronic, and structural degrees of freedom. Here, we combine angle-resolved photoemission spectroscopy, phonon mode calculation, and chemical doping to elucidate the driving mechanism of the root3*root3 charge order in a newly discovered kagome metal ScV6Sn6. In contrast to the case of the archetype kagome system AV3Sb5 (A= K, Rb, Cs), the van Hove singularities in ScV6Sn6 remain intact across the charge order transition, indicating a marginal role of the electronic instability from the V kagome lattice. Instead, we identified a three-dimensional band with dominant planar Sn character opening a large charge order gap of 260 meV and strongly reconstructing the Fermi surface. Our complementary phonon dispersion calculations further emphasize the role of the structural components other than the V kagome lattice by revealing the unstable planar Sn and Sc phonon modes associated to the root3*root3 phase. Finally, in the constructed phase diagram of Sc(V1-xCrx)6Sn6, the charge order remains robust in a wide doping range x = 0 ~ 0.10 against the Fermi level shift up to ~ 120 meV, further making the electronic scenarios such as Fermi surface or saddle point nesting unlikely. Our multimodal investigations demonstrate that the physics of ScV6Sn6 is fundamentally different from the canonical kagome metal AV3Sb5, uncovering a new mechanism to induce symmetry-breaking phase transition in kagome lattice materials.

Computed tomography (CT) has been used worldwide for decades as one of the most important non-invasive tests in assisting diagnosis. However, the ionizing nature of X-ray exposure raises concerns about potential health risks such as cancer. The desire for lower radiation dose has driven researchers to improve the reconstruction quality, especially by removing noise and artifacts. Although previous studies on low-dose computed tomography (LDCT) denoising have demonstrated the potential of learning-based methods, most of them were developed on the simulated data collected using Radon transform. However, the real-world scenario significantly differs from the simulation domain, and the joint optimization of denoising with the modern CT image reconstruction pipeline is still missing. In this paper, for the commercially available third-generation multi-slice spiral CT scanners, we propose a two-stage method that better exploits the complete reconstruction pipeline for LDCT denoising across different domains. Our method makes good use of the high redundancy of both the multi-slice projections and the volumetric reconstructions while avoiding the collapse of information in conventional cascaded frameworks. The dedicated design also provides a clearer interpretation of the workflow. Through extensive evaluations, we demonstrate its superior performance against state-of-the-art methods.

Additional file 1: Fig. S1. No alteration of cell viability by IFN-γ-iMSC-EVs. Human dermal fibroblasts (left panel) and keratinocytes (right panel) were used to test the effects of cell viability on IFN-γ-iMSC-EVs. Fig. S2. Survival rate (A) and body weight (B) were assessed during 4 weeks following IFN-γ-iMSC-EVs treatment. Table S7. Sequences of primers used for real-time qPCR analysis.

Catalytic CO2 conversion to renewable fuel is of utmost importance to establish a carbon-neutral society. Bioelectrochemical CO2 reduction, in which a solid cathode interfaces with CO2-reducing bacteria, represents a promising approach for renewable and sustainable fuel production. The rational design of biocatalysts in the biohybrid system is imperative to effectively reduce CO2 into valuable chemicals. Here, we introduce methanol adapted Sporomusa ovata (S. ovata) to enhance the slow metabolic activity of wild-type microorganisms to our semiconductive silicon nanowires (Si NWs) array for efficient CO2 reduction. The adapted whole-cell catalysts enable an enhancement of CO2 fixation with a superior faradaic efficiency on the poised Si NWs cathode. The synergy of the high-surface-area cathode and the adapted strain achieves a CO2-reducing current density of 0.88 ± 0.11 mA/cm2, which is 2.4-fold higher than the wild-type strain. This new generation of biohybrids using adapted S. ovata also decreases the charge transfer resistance at the cathodic interface and facilitates the faster charge transfer from the solid electrode to bacteria.

Spin-orbit entangled pseudospins hold promise for a wide array of exotic magnetism ranging from a Heisenberg antiferromagnet to a Kitaev spin liquid depending on the lattice and bonding geometry, but many of the host materials suffer from lattice distortions and deviate from idealized models in part due to inherent strong pseudospin-lattice coupling. Here, we report on the synthesis of a magnetic superlattice comprising the single ($n$=1) and the double ($n$=2) layer members of the Ruddlesden-Popper series iridates Sr$_{n+1}$Ir$_{n}$O$_{3n+1}$ alternating along the $c$-axis, and provide a comprehensive study of its lattice and magnetic structures using scanning transmission electron microscopy, resonant elastic and inelastic x-ray scattering, third harmonic generation measurements and Raman spectroscopy. The superlattice is free of the structural distortions reported for the parent phases and has a higher point group symmetry, while preserving the magnetic orders and pseudospin dynamics inherited from the parent phases, featuring two magnetic transitions with two symmetry-distinct orders. We infer weaker pseudospin-lattice coupling from the analysis of Raman spectra and attribute it to frustrated magnetic-elastic couplings. Thus, the superlattice expresses a near ideal network of effective spin-one-half moments on a square lattice.

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Additional file 1: Fig. S1. Protein expression of PPARs in iMSCs. PPAR��/��/��protein expression in iMSCs treated with pan PPAR agonist. Human adipocyte is used as positive control. Fig. S2. Validation of gene expression in iMSCs and pan PPAR-iMSCs.Data are represented as mean �� SD. n = 4.*P

We present a novel methodology for control of neural circuits based on deep reinforcement learning. Our approach achieves aimed behavior by generating external continuous stimulation of existing neural circuits (neuromodulation control) or modulations of neural circuits architecture (connectome control). Both forms of control are challenging due to nonlinear and recurrent complexity of neural activity. To infer candidate control policies, our approach maps neural circuits and their connectome into a grid-world like setting and infers the actions needed to achieve aimed behavior. The actions are inferred by adaptation of deep Q-learning methods known for their robust performance in navigating grid-worlds. We apply our approach to the model of \textit{C. elegans} which simulates the full somatic nervous system with muscles and body. Our framework successfully infers neuropeptidic currents and synaptic architectures for control of chemotaxis. Our findings are consistent with in vivo measurements and provide additional insights into neural control of chemotaxis. We further demonstrate the generality and scalability of our methods by inferring chemotactic neural circuits from scratch., Comment: Please see the associated Video at: https://youtu.be/ixsUMfb9m_U

Recently, ICT ecosystems are changing rapidly due to the increasing number of innovative products and services in these ecosystems. Among them, SNS is one of the most important elements that make up the ICT ecosystem. With the phenomenal boom of personal SNS, information and knowledge sharing within an organization through enterprise SNS is increasing exponentially. Many companies are adopting and using intranet-based SNS for communicating and sharing information within the firm. However, there have not been many studies exploring the impact of group intentions on the SNS service within a firm. In this study, we investigate user intentions as they relate to intranet-based SNS as better information and knowledge sharing communication tools which improve existing internal communication methods due to their system-wide implementation of a top-down approach and mandatory participation. To do this, this study developed a research model for an intranet-based SNS service based on social exchange theory, social learning theory, motivation theory and We-Intention theory. The results indicated that employees desire to use SNS service when they perceive a reciprocal benefit for themselves and other employees. Usability only affects desire and sociability affects what is termed here as We-Intention. However, sociability's result is opposite in that sociability directly affects We-Intention. Considering that communication and interaction between group members are recently increasingly important, this research results are academically significant because they suggest a meaningful implication to vitalizing information and knowledge sharing in organizations through the use of intranet-based SNS.

This study argues that American views of Korea during the period of Japanese colonial rule (1910-1945) shaped U.S. policy toward Korea in the colonial period and after, setting the stage for direct U.S. involvement in Korea's post-liberation years after 1945. Korean nationalists perceived the U.S. as a special ally and a model country, and expected it to play a positive role in resolving Korea's colonial status. In fact, American views of Korea in the early twentieth century were mixed, and depended greatly on the respective observers' relationship to Korea--whether as missionary, as scholar, or as diplomat. At the same time, Japan played a crucial role in mediating American views, reflecting the Asia colonizer's interest in winning international approval for its imperialist project. When Korean-American diplomatic relations began in the late nineteenth century, Americans observers typically regarded Korea as an uncivilized but distinct Asian country. This perception of backwardness persisted into the early twentieth century, even as Korea lost its status as a nation-state with the Japanese annexation of 1910. Awareness of Japanese subjugation of Korea would expand significantly in the period 1919-1922, as journalists and missionaries conveyed news of the March First Movement to the American public and Korean nationalists countered Japanese government efforts to influence international opinion. Nationalist efforts to influence U.S. policymaking in the 1920s and 1930s were persistent but never fully successful, in part because of Korean factional rivalries, changing Japanese strategies of colonial control, and American diplomats' desire to protect U.S. colonial interests in the Philippines. Although Korean nationalists failed to accomplish their ultimate goal of participating directly in the U.S. government's wartime discussions on Korea in the early 1940s, they nevertheless succeeded in making the American public aware that Korea was a cultural and racial entity distinct from Japan. This awareness would lay a foundation for American direct intervention in Korean political, social, and military problems after 1945.

The layered vanadium antimonides AV3Sb5 (A = K, Rb, Cs) are a recently discovered family of topological kagome metals with a rich phenomenology of strongly correlated electronic phases including charge order and superconductivity. Understanding how the singularities inherent to the kagome electronic structure are linked to the observed many-body phases is a topic of great interest and relevance. Here, we combine angle-resolved photoemission spectroscopy and density functional theory to reveal multiple kagome-derived van Hove singularities (vHs) coexisting near the Fermi level of CsV3Sb5 and analyze their contribution to electronic symmetry breaking. Intriguingly, the vHs in CsV3Sb5 have two distinct flavors - p-type and m-type - which originate from their pure and mixed sublattice characters, respectively. This twofold vHs is unique property of the kagome lattice, and its flavor critically determines the pairing symmetry and ground states emerging in AV3Sb5 series. We establish that, among the multiple vHs in CsV3Sb5, the m-type vHs of the dxz/dyz kagome band and the p-type vHs of the dxy/dx2-y2 kagome band cross the Fermi level to set the stage for electronic symmetry breaking. The former band exhibits pronounced Fermi surface nesting, while the latter contributes via higher-order vHs. Our work reveals the essential role of kagome-derived vHs for the collective phenomena realized in the AV3Sb5 family, paving the way to a deeper understanding of strongly correlated topological kagome systems., Comment: Submitted to Nature Physics on May 28th, 2021. A revised version will appear in Nature Physics