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Spin Hall effect, an electric generation of spin current, allows for efficient control of magnetization. Recent theory revealed that orbital Hall effect creates orbital current, which can be much larger than spin-Hall-induced spin current. However, orbital current cannot directly exert a torque on a ferromagnet, requiring a conversion process from orbital current to spin current. Here, we report two effective methods of the conversion through spin-orbit coupling engineering, which allows us to unambiguously demonstrate orbital-current-induced spin torque, or orbital Hall torque. We find that orbital Hall torque is greatly enhanced by introducing either a rare-earth ferromagnet Gd or a Pt interfacial layer with strong spin-orbit coupling in Cr/ferromagnet structures, indicating that the orbital current generated in Cr is efficiently converted into spin current in the Gd or Pt layer. Our results offer a pathway to utilize the orbital current to further enhance the magnetization switching efficiency in spin-orbit-torque-based spintronic devices. Manipulation of the magnetization is of major importance in spintronics. The authors demonstrate that an electric field triggers a transverse flow of orbital moment: the so-called orbital Hall effect. This enables the efficient magnetization control, holding the promise for fast and miniaturized memories and sensors.

Although arthropods are important viral vectors, the biodiversity of arthropod viruses, as well as the role that arthropods have played in viral origins and evolution, is unclear. Through RNA sequencing of 70 arthropod species we discovered 112 novel viruses that appear to be ancestral to much of the documented genetic diversity of negative-sense RNA viruses, a number of which are also present as endogenous genomic copies. With this greatly enriched diversity we revealed that arthropods contain viruses that fall basal to major virus groups, including the vertebrate-specific arenaviruses, filoviruses, hantaviruses, influenza viruses, lyssaviruses, and paramyxoviruses. We similarly documented a remarkable diversity of genome structures in arthropod viruses, including a putative circular form, that sheds new light on the evolution of genome organization. Hence, arthropods are a major reservoir of viral genetic diversity and have likely been central to viral evolution. Many illnesses, including influenza, hemorrhagic fever, and rabies, are caused by a group of viruses called negative-sense RNA viruses. The genetic information—or genome—of these viruses is encoded in strands of RNA that must be copied before they can be translated into the proteins needed to build new viruses. It is currently known that there are at least eight different families of these viruses, which have a wide range of shapes and sizes and arrange their RNA in different ways. Insects, spiders, and other arthropods carry many different RNA viruses. Many of these viruses have not previously been studied, and those that have been studied so far are mainly those that cause diseases in humans and other vertebrates. Researchers therefore only know a limited amount about the diversity of the negative-sense RNA viruses that arthropods harbor and how these viruses evolved. Studying how viruses evolve helps scientists to understand what makes some viruses deadly and others harmless and can also help develop treatments or vaccines for the diseases caused by the viruses. Li, Shi, Tian, Lin, Kang et al. collected 70 species of insects, spiders, centipedes, and other arthropods in China and sequenced all the negative-sense RNA viruses in the creatures. This revealed an enormous number of negative-sense RNA viruses, including 112 new viruses. Many of the newly discovered arthropod viruses appear to be the ancestors of disease-causing viruses, including influenza viruses and the filoviruses—the group that includes the Ebola virus. Indeed, it appears that arthropods host many—if not all—of the negative-sense RNA viruses that cause disease in vertebrates and plants. While documenting the new RNA viruses and how they are related to each other, Li et al. found many different genome structures. Some genomes were segmented, which may play an important role in evolution as segments can be easily swapped to create new genetic combinations. Non-segmented and circular genomes were also found. This genetic diversity suggests that arthropods are likely to have played a key role in the evolution of new viruses by acting as a site where many different viruses can interact and exchange genetic information.

Hazardous organic pollutants represent a threat to human, animal, and environmental health. If left unmanaged, these pollutants could cause concern. Many researchers have stepped up efforts to find more sustainable and cost-effective alternatives to using hazardous chemicals and treatments to remove existing harmful pollutants. Environmental biotechnology, such as bioremediation and phytoremediation, is a promising field that utilizes natural resources including microbes and plants to eliminate toxic organic contaminants. This technology offers an attractive alternative to other conventional remediation processes because of its relatively low cost and environmentally-friendly method. This review discusses current biological technologies for the removal of organic contaminants, including chlorinated hydrocarbons, focusing on their limitation and recent efforts to correct the drawbacks.

We examine whether family firms invest more in employee relations than nonfamily firms. Using the variation in state-level changes in inheritance, gift, and estate taxes as an exogenous shock to family control, we find that family firms, particularly those in which a founder serves as chief executive officer or those in which a family member serves as a director on the board, treat their employees better than nonfamily firms. More importantly, family firms focus on investing in employee relations that help alleviate labor-related conflicts and controversies, possibly to avoid a negative family reputation among stakeholders. Family firms’ better treatment of their employees is also evident when we use a difference-in-difference test to exploit changes in family firm status due to (sudden) deaths of family members and firms’ inclusion in Fortune ’s “100 Best Companies to Work For” list to identify employee-friendly treatment. We further find that family firms in the early stage of their life cycle invest more in employee relations when they operate in labor-intensive industries in which the benefits from family owners’ monitoring of employees are expected to be large. Moreover, we find that although nonfamily firms’ investment in employee relations is impeded by several constraints, such as short-term investor pressure, managerial myopia, and managerial agency problems, family firms do not suffer from such constraints. These findings help explain why underinvestment in employee relations is prevalent in public firms despite potential long-term benefits from such intangible investment. This paper was accepted by Neng Wang, finance.

Earth's biosphere witnessed the first major extinction event in the Phanerozoic during the Cambrian Age 4, with a genera loss up to ∼45%. The traditional view suggested that marine anoxia was the main cause of the biotic crisis, yet recent geochemical investigations yielded highly debated opinions on marine redox states during the Cambrian Age 4. Herein, we supplement new geochemical evidence for expanded marine euxinia at the extinction intervals on the Yangtze Platform, South China. Most importantly, modern‐level sedimentary δ98Mo (∼+2.34‰) records were most parsimoniously explained by transitory expansion of continental margin euxinia and concomitant intensification of sedimentary Mo sequestration via Fe‒Mn shuttles in the global ocean. The results clarify global marine redox conditions during the Cambrian Age 4, and lend firm support to a causal link between expanded marine euxinia and the extinction event. Plain Language Summary Marine life experienced the first major mass extinction during the Cambrian Age 4 (∼509–514 Ma) right after the Cambrian explosion, with a genera loss up to ∼45%. The mass extinction was traditionally attributed to expanded marine anoxia in the global ocean based on lithological changes, but geochemical evidence for this scenario is still lacking. Molybdenum (Mo) isotopes can be used to track global marine redox states in ancient oceans. Herein, new Mo isotope data revealed transitory expansion of sulfidic waterbodies on in the global ocean at the major mass extinction intervals. Sulfidic waters enriched in H2S are lethal for marine animals. Therefore, expanded sulfidic waterbodies in the global ocean could have served as a major driver for the mass extinction event. Key Points Dynamic marine Mo cycling via Fe‒Mn shuttles during the Cambrian Age 4 is revealed Robust Mo isotope evidence for expanded continental margin euxinia in the global ocean during mass extinction Firm support to a causal link between expanded marine euxinia and the extinction event

Recently, novel core–shell MOF@COF hybrids display excellent performance in various fields because of their inherited advantages from their parent MOFs and/or COFs. However, it is still a grand challenge to adjust the morphology of MOFs and/or COFs for consequent performance improvement. Herein, a Ti‐MOF@TpTt hybrid coated with ultra‐thin COF nanobelt, which is different from the fibrillar‐like parent COF, is successfully synthesized through a sequential growth strategy. The as‐obtained Pd decorated Ti‐MOF@TpTt catalyst exhibits much higher photocatalytic performance than those of Ti‐MOF, TpTt‐COF, and Ti‐MOF@TpTt hybrids with fibrillar‐like COF shell for the photocatalytic cascade reactions of ammonia borane (AB) hydrolysis and nitroarenes hydrogenation. These can be attributed to its high BET surface area, core–shell structure, and type II heterojunction, which offers more accessible active sites and improves the separation efficiency of photo‐generated carriers. Finally, the possible mechanisms of the cascade reaction are also proposed to well explain the improved performance of this photocatalytic system. This work presents a constructive route for designing core–shell MOF@COF hybrids with controllable morphology adjustment of COF shell, leading to the improved photocatalytic ability to broaden the applications of MOF/COF hybrid materials. A novel Ti‐MOF@TpTt hybrid, which coats with ultrathin TpTt nanobelt as the shell, is successfully synthesized through a sequential growth strategy. The as‐obtained Pd decorated Pd@Ti‐MOF@TpTt catalyst exhibits much higher photocatalytic performance than Ti‐MOF, TpTt‐COF, and the hybrids with fibrillar‐like COF‐shell for the cascade reactions of AB hydrolysis and nitroarenes hydrogenation.

Serologic and molecular surveillance of serum collected from 152 suspected scrub typhus patients in Myanmar revealed Orientia tsutsugamushi of genotypic heterogeneity. In addition, potential co-infection with severe fever with thrombocytopenia syndrome virus was observed in 5 (3.3%) patients. Both scrub typhus and severe fever with thrombocytopenia syndrome are endemic in Myanmar.

Effective pyroptosis induction is a promising approach to potentiate cancer immunotherapy. However, the actual efficacy of the present pyroptosis inducers can be weakened by successive biological barriers. Here, a cascaded pH‐activated supramolecular nanoprodrug (PDNP) with a stepwise size shrinkage property is developed as a pyroptosis inducer to boost antitumor immune response. PDNPs comprise multiple poly(ethylene glycol) (PEG) and doxorubicin (DOX) drug–polymer hybrid repeating blocks conjugated by ultra‐pH‐sensitive benzoic imine (bzi) and hydrazone (hyd) bonds. The PEG units endow its “stealth” property and ensure sufficient tumor accumulation. A sharp switch in particle size and detachment of PEG shielding can be triggered by the acidic extracellular pH to achieve deep intratumor penetration. Following endocytosis, second‐stage size switching can be initiated by more acidic endolysosomes, and PDNPs disassociate into ultrasmall cargo to ensure accurate intracellular delivery. The cascaded pH activation of PDNPs can effectively elicit gasdermin E (GSDME)‐mediated pyroptosis to enhance the immunological response. In combination with anti‐PD‐1 antibody, PDNPs can amplify tumor suppression and extend the survival of mice, which suggests a powerful immune adjuvant and pave the way for high‐efficiency immune checkpoint blockade therapy. A cascaded pH‐activated supramolecular nanoprodrug (PDNP) with mutistage size shrinkage property is developed to combat the successive drug delivery barriers. The size‐transformable PDNPs can precise intracellular delivery drug for effectively eliciting pyroptosis and augmenting antitumor immune response, favorable for boosting checkpoint blockade‐based immunotherapy.

Many terminal sliding mode controllers (TSMCs) have been suggested to obtain exact tracking control of robotic manipulators in finite time. The ordinary method is based on TSMCs that secure trajectory tracking under the assumptions such as the known robot dynamic model and the determined upper boundary of uncertain components. Despite tracking errors that tend to zero in finite time, the weakness of TSMCs is chattering, slow convergence speed, and the need for the exact robot dynamic model. Few studies are handling the weakness of TSMCs by using the combination between TSMCs and finite-time observers. In this paper, we present a novel finite-time fault tolerance control (FTC) method for robotic manipulators. A finite-time fault detection observer (FTFDO) is proposed to estimate all uncertainties, external disturbances, and faults accurately and on time. From the estimated information of FTFDO, a novel finite-time FTC method is developed based on a new finite-time terminal sliding surface and a new finite-time reaching control law. Thanks to this approach, the proposed FTC method provides a fast convergence speed for both observation error and control error in finite time. The operation of the robot system is guaranteed with expected performance even in case of faults, including high tracking accuracy, small chattering behavior in control input signals, and fast transient response with the variation of disturbances, uncertainties, or faults. The stability and finite-time convergence of the proposed control system are verified that they are strictly guaranteed by Lyapunov theory and finite-time control theory. The simulation performance for a FARA robotic manipulator proves the proposed control theory’s correctness and effectiveness.

For magnetic levitation systems subject to dynamical uncertainty and exterior perturbations, we implement a real-time Prescribed Performance Control (PPC). A modified function of Global Fast Terminal Sliding Mode Manifold (GFTSMM) based on the transformed error of the novel PPC is introduced; hence, the error variable quickly converges to the equilibrium point with the prescribed performance, which means that maximum overshoot and steady-state of the controlled errors will be in a knowledge-defined boundary. To enhance the performance of Global Fast Terminal Sliding Mode Control (GFTSMC) and to reduce chattering in the control input, a modified third-order sliding mode observer (MTOSMO) is proposed to estimate the whole uncertainty and external disturbance. The combination of the GFTSMC, PPC, and MTOSMO generates a novel solution ensuring a finite-time stable position of the controlled ball and the possibility of performing different orbit tracking missions with an impressive performance in terms of tracking accuracy, fast convergence, stabilization, and chattering reduction. It also possesses a simple design that is suitable for real-time applications. By using the Lyapunov-based method, the stable evidence of the developed method is fully verified. We implement a simulation and an experiment on the laboratory magnetic levitation model to demonstrate the improved performance of the developed control system.