Distributed quantum metrology can enhance the sensitivity for sensing spatially distributed parameters beyond the classical limits. Here we demonstrate distributed quantum phase estimation with ...discrete variables to achieve Heisenberg limit phase measurements. Based on parallel entanglement in modes and particles, we demonstrate distributed quantum sensing for both individual phase shifts and an averaged phase shift, with an error reduction up to 1.4 dB and 2.7 dB below the shot-noise limit. Furthermore, we demonstrate a combined strategy with parallel mode entanglement and multiple passes of the phase shifter in each mode. In particular, our experiment uses six entangled photons with each photon passing the phase shifter up to six times, and achieves a total number of photon passes N = 21 at an error reduction up to 4.7 dB below the shot-noise limit. Our research provides a faithful verification of the benefit of entanglement and coherence for distributed quantum sensing in general quantum networks.Distributed quantum metrology is demonstrated for both individual and averaged phase shifts by using discrete-variable entangled photons. An error reduction of 4.7 dB below the shot-noise limit is achieved when a total number of photon passes is 21.
Herein we describe a mild method for the dual C(sp3)−H bond functionalization of saturated nitrogen‐containing heterocycles through a sequential visible‐light photocatalyzed dehydrogenation/2+2 ...cycloaddition procedure. As a complementary approach to the well‐established use of iminium ion and α‐amino radical intermediates, the elusive cyclic enamine intermediates were effectively generated by photoredox catalysis under mild conditions and efficiently captured by acetylene esters to form a wide array of bicyclic amino acid derivatives, thus enabling the simultaneous functionalization of two vicinal C(sp3)−H bonds.
A great team: A dual C(sp3)−H bond functionalization strategy was developed by merging dehydrogenation under visible‐light photocatalysis with a 2+2 cycloaddition reaction in a sequential process. This method enabled cyclobutene rings to be fused to various saturated nitrogen‐containing heterocycles to produce a series of cyclic amino acid derivatives.
A synergistic catalytic method combining photoredox catalysis, hydrogen‐atom transfer, and proton‐reduction catalysis for the dehydrogenative silylation of alkenes was developed. With this approach, ...a highly concise route to substituted allylsilanes has been achieved under very mild reaction conditions without using oxidants. This transformation features good to excellent yields, operational simplicity, and high atom economy. Based on control experiments, a possible reaction mechanism is proposed.
A synergistic catalytic method of combining photoredox catalysis, hydrogen‐atom transfer, and proton‐reduction catalysis for the dehydrogenative silylation of alkenes was developed. The reaction features high regioselectivity, excellent tolerance of functional groups, wide substrate scope, and mild reaction conditions. Moreover, this oxidant‐free system offers a cleaner and more efficient method beyond traditional catalysis, which requires either stoichiometric or excess amounts of oxidants.
This trend article highlights recent and important progresses in the area of supramolecular polymeric systems from structural control to functional assembly, focusing on supramolecular polymers with ...controllable architectures, covalent polymerization facilitated by supramolecular approaches as well as simultaneous covalent and noncovalent polymerization, and polymer self-assembly with highly ordered structures and unique functions. Future challenges and opportunities for this prosperously developing realm of supramolecular polymeric systems are also discussed.
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The interplay between polymer science and supramolecular chemistry leads to formation of various supramolecular polymeric systems. Owing to the dynamic nature of noncovalent interactions, supramolecular polymeric systems may be of abundant supramolecular structures, thus endowed with many fascinating properties and functions such as reversibility, adaptiveness, self-healing, and stimuli-responsiveness. In this trend article, we intend to highlight recent and important progresses in the area of supramolecular polymeric systems from structural control to functional assembly, focusing on supramolecular polymers with controllable architectures, covalent polymerization facilitated by supramolecular approaches as well as simultaneous covalent and noncovalent polymerization, and polymer self-assembly with highly ordered structures and unique functions. It is anticipated that this line of research will reflect the current status and future trends in this prosperously developing realm of supramolecular polymeric systems.
Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; ...however, the role of miRNA‐373‐3p (miR‐375‐3p) in CRC remains unclear. The current study aimed to explore the potential function of miR‐375‐3p in 5‐fluorouracil (5‐FU) resistance. MicroRNA‐375‐3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5‐FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR‐375‐3p, and TYMS knockdown exerted similar effects as miR‐375‐3p overexpression on the CRC cellular response to 5‐FU. Lipid‐coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5‐FU and miR‐375‐3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR‐375 + 5‐FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR‐375‐3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5‐FU.
Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Our results suggest that the restoration of microRNA‐375‐3p levels could be a future novel therapeutic strategy to modulate and enhance chemosensitivity to 5‐fluorouracil treatment in CRC.
Quantum repeaters—important components of a scalable quantum internet—enable entanglement to be distributed over long distances. The standard paradigm for a quantum repeater relies on the necessary, ...demanding requirement of quantum memory. Despite significant progress, the limited performance of quantum memory means that making practical quantum repeaters remains a challenge. Remarkably, a proposed all-photonic quantum repeater avoids the need for quantum memory by harnessing the graph states in the repeater nodes. Here we perform an experimental demonstration of an all-photonic quantum repeater. By manipulating a 12-photon interferometer, we implement a 2 × 2 parallel all-photonic quantum repeater, and observe an 89% enhancement of entanglement-generation rate over standard parallel entanglement swapping. These results provide a new approach to designing repeaters with efficient single-photon sources and photonic graph states, and suggest that the all-photonic scheme represents an alternative path—parallel to matter-memory-based schemes—towards realizing practical quantum repeaters.
Due to the significance of hybrid systems in drug discovery, there is an urgent need to assemble multiple biologically active ingredients into a single molecule. Here, we report a general ...transition‐metal‐free selective C−H benzylation of tertiary arylamines in good to excellent yields with a broad substrate scope and high functional‐group tolerance under mild conditions. Besides arylamines, some other benzene derivatives also readily furnished the corresponding diaryl methane derivatives with this protocol. A series of control experiments and theoretical calculations indicated that this transition‐metal‐free reaction is a dearomatization‐aromatization process.
All in one molecule: Here, we report a mild transition‐metal‐free method for direct selective C−H benzylation of tertiary arylamines and other benzene derivatives in good to excellent yields with good functional group tolerance by a dearomatization‐aromatization sequence, which provides a general way to couple biologically significant tertiary arylamines and benzhydryl motifs into one molecule.
Creating large-scale entanglement lies at the heart of many quantum information processing protocols and the investigation of fundamental physics. For multipartite quantum systems, it is crucial to ...identify not only the presence of entanglement but also its detailed structure. This is because in a generic experimental situation with sufficiently many subsystems involved, the production of so-called genuine multipartite entanglement remains a formidable challenge. Consequently, focusing exclusively on the identification of this strongest type of entanglement may result in an all or nothing situation where some inherently quantum aspects of the resource are overlooked. On the contrary, even if the system is not genuinely multipartite entangled, there may still be many-body entanglement present in the system. An identification of the entanglement structure may thus provide us with a hint about where imperfections in the setup may occur, as well as where we can identify groups of subsystems that can still exhibit strong quantum-information-processing capabilities. However, there is no known efficient methods to identify the underlying entanglement structure. Here, we propose two complementary families of witnesses for the identification of such structures. They are based, respectively, on the detection of entanglement intactness and entanglement depth, each applicable to an arbitrary number of subsystems and whose evaluation requires only the implementation of solely two local measurements. Our method is also robust against noises and other imperfections, as reflected by our experimental implementation of these tools to verify the entanglement structure of five different eight-photon entangled states. In particular, we demonstrate how their entanglement structure can be precisely and systematically inferred from the experimental measurement of these witnesses. In achieving this goal, we also illustrate how the same set of data can be classically postprocessed to learn the most about the measured system.
Enhancing the systemic distribution of a bioactive compound by exploiting the vascular transport system of a plant presents a means of reducing both the volume and frequency of pesticide/fungicide ...application. The foliar uptake of the glucose–fipronil conjugate N-3-cyano-1-2,6-dichloro-4-(trifluoromethyl)phenyl-4-(trifluoromethyl)sulfinyl-1H-pyrazol-5-yl-1-(β-d-glucopyranosyl)-1H-1,2,3-triazole-4-methanamine (GTF) achieved in castor bean (Ricinus communis) and its transport via the phloem are known to be mediated by monosaccharide transporter(s) MST(s), although neither the identity of the key MST(s) involved nor the mechanistic basis of its movement have yet to be described. On the basis of homology with Arabidopsis thaliana sugar transporters, the castor bean genome was concluded to harbor 53 genes encoding a sugar transporter, falling into the eight previously defined subfamilies INT, PMT, VGT, STP, ERD6, pGlucT, TMT, and SUT. Transcriptional profiling identified the product of RcSTP1 as a candidate for mediating GTF uptake, because this gene was induced by exposure of the plant to GTF. When RcSTP1 was transiently expressed in onion epidermis cells, the site of RcSTP1 deposition was shown to be the plasma membrane. A functional analysis based on RcSTP1 expression in Xenopus laevis oocytes demonstrated that its product has a high affinity for GTF. The long-distance root-to-shoot transport of GTF was enhanced in a transgenic soybean chimera constitutively expressing RcSTP1.
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