Reduction of the uranium(III) metallocene (η5‐C5iPr5)2UI (1) with potassium graphite produces the “second‐generation” uranocene (η5‐C5iPr5)2U (2), which contains uranium in the formal divalent ...oxidation state. The geometry of 2 is that of a perfectly linear bis(cyclopentadienyl) sandwich complex, with the ground‐state valence electron configuration of uranium(II) revealed by electronic spectroscopy and density functional theory to be 5f3 6d1. Appreciable covalent contributions to the metal‐ligand bonds were determined from a computational study of 2, including participation from the uranium 5f and 6d orbitals. Whereas three unpaired electrons in 2 occupy orbitals with essentially pure 5f character, the fourth electron resides in an orbital defined by strong 7s‐6dz2
mixing.
A new generation: Reduction of the uranium(III) metallocene (η5‐C5iPr5)2UI with potassium graphite produces the “second‐generation” uranocene (η5‐C5iPr5)2U, which contains uranium in the formal divalent oxidation state. The geometry of (η5‐C5iPr5)2U is that of a perfectly linear bis(cyclopentadienyl) sandwich complex.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
By using transitionless quantum driving algorithm (TQDA), we present an efficient scheme for the shortcuts to the holonomic quantum computation (HQC). It works in decoherence-free subspace (DFS) and ...the adiabatic process can be speeded up in the shortest possible time. More interestingly, we give a physical implementation for our shortcuts to HQC with nitrogen-vacancy centers in diamonds dispersively coupled to a whispering-gallery mode microsphere cavity. It can be efficiently realized by controlling appropriately the frequencies of the external laser pulses. Also, our scheme has good scalability with more qubits. Different from previous works, we first use TQDA to realize a universal HQC in DFS, including not only two noncommuting accelerated single-qubit holonomic gates but also a accelerated two-qubit holonomic controlled-phase gate, which provides the necessary shortcuts for the complete set of gates required for universal quantum computation. Moreover, our experimentally realizable shortcuts require only two-body interactions, not four-body ones, and they work in the dispersive regime, which relax greatly the difficulty of their physical implementation in experiment. Our numerical calculations show that the present scheme is robust against decoherence with current experimental parameters.
Paternal environmental inputs can influence various phenotypes in offspring, presenting tremendous implications for basic biology and public health and policy. However, which signals function as a ...nexus to transmit paternal environmental inputs to offspring remains unclear. Here we show that offspring of fathers with inflammation exhibit metabolic disorders including glucose intolerance and obesity. Deletion of a mouse tRNA RNase, Angiogenin (Ang), abolished paternal inflammation-induced metabolic disorders in offspring. Additionally, Ang deletion prevented the inflammation-induced alteration of 5'-tRNA-derived small RNAs (5'-tsRNAs) expression profile in sperm, which might be essential in composing a sperm RNA 'coding signature' that is needed for paternal epigenetic memory. Microinjection of sperm 30-40 nt RNA fractions (predominantly 5'-tsRNAs) from inflammatory Ang
males but not Ang
males resulted in metabolic disorders in the resultant offspring. Moreover, zygotic injection with synthetic 5'-tsRNAs which increased in inflammatory mouse sperm and decreased by Ang deletion partially resembled paternal inflammation-induced metabolic disorders in offspring. Together, our findings demonstrate that Ang-mediated biogenesis of 5'-tsRNAs in sperm contributes to paternal inflammation-induced metabolic disorders in offspring.
We propose a high-efficiency three-party quantum key agreement protocol, by utilizing two-photon polarization-entangled Bell states and a few single-photon polarization states as the information ...carriers, and we use the quantum dense coding method to improve its efficiency. In this protocol, each participant performs one of four unitary operations to encode their sub-secret key on the passing photons which contain two parts, the first quantum qubits of Bell states and a small number of single-photon states. At the end of this protocol, based on very little information announced by other, all participants involved can deduce the same final shared key simultaneously. We analyze the security and the efficiency of this protocol, showing that it has a high efficiency and can resist both outside attacks and inside attacks. As a consequence, our protocol is a secure and efficient three-party quantum key agreement protocol.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this work we measure two important phenomenological parameters of corona (and hot accretion flow) in black hole X-ray binaries: the photon index Γ and the electron temperature . Thanks to the ...capability of the Nuclear Spectroscopic Telescope Array in hard X-rays, we measure these two parameters over six orders of magnitude in the 0.1-100 keV X-ray luminosity , from ∼5 × 1038 down to as low as ∼5 × 1032 . We confirm the existence of a "V"-shaped correlation between Γ and . Surprisingly, we observe a "Λ"-shaped correlation between and . The "cooler when brighter" branch in the high-luminosity regime ( 3 × 1036 ) agrees with previous results and can be understood under the existing model of Compton scattering in the corona. On the other hand, the apparent "cooler when fainter" (positive - correlation) branch in the low-luminosity regime ( 3 × 1036 ) is unexpected, thus it puts a new challenge to existing models of hot accretion flow/corona.
Parkinson's disease (PD) is the second most prevalent central nervous system (CNS) degenerative disease. Oxidative stress is one of key contributors to PD. Nuclear factor erythroid‐2‐related factor 2 ...(Nrf2) is considered to be a master regulator of many genes involved in anti‐oxidant stress to attenuate cell death. Therefore, activation of Nrf2 signalling provides an effective avenue to treat PD. Ellagic acid (EA), a natural polyphenolic contained in fruits and nuts, possesses amounts of pharmacological activities, such as anti‐oxidant stress and anti‐inflammation. Recent studies have confirmed EA could be used as a neuroprotective agent in neurodegenerative diseases. Here, mice subcutaneous injection of rotenone (ROT)‐induced DA neuronal damage was performed to investigate EA‐mediated neuroprotection. In addition, adult Nrf2 knockout mice and different cell cultures including MN9D‐enciched, MN9D‐BV‐2 and MN9D‐C6 cell co‐cultures were applied to explore the underlying mechanisms. Results demonstrated EA conferred neuroprotection against ROT‐induced DA neurotoxicity. Activation of Nrf2 signalling was involved in EA‐mediated DA neuroprotection, as evidenced by the following observations. First, EA activated Nrf2 signalling in ROT‐induced DA neuronal damage. Second, EA generated neuroprotection with the presence of astroglia and silence of Nrf2 in astroglia abolished EA‐mediated neuroprotection. Third, EA failed to produce DA neuroprotection in Nrf2 knockout mice. In conclusion, this study identified EA protected against DA neuronal loss via an Nrf2‐dependent manner.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Understanding the relationships between ecosystem services (ES) and their underlying socioecological drivers is essential for forming the efficient management decisions of ecosystems. We use a large ...watershed area as a case-study to analyze trade-offs/synergies and bundles of ESs and identify the associated socioecological variables (SEVs). This study assessed the supply of 7 ES indicators, namely, three provisioning services (crop production, livestock production, and industrial production), three regulating services (water conservation, soil conservation, and carbon sequestration), and one cultural service (recreation), across 65 municipalities in the Yellow River Basin (YRB) in China. We analyzed the paired trade-offs/synergies using Spearman's coefficient and identified the ES bundles (ESBs) by applying principal component analysis and K-means clustering. Subsequently, we detected the SEVs that affect the ES supply using the geo-detector model and characterized the associations between ESBs and socioecological clusters according to the spatial overlap. The results demonstrated that the synergies between ESs substantially exceeded the trade-offs, among which the strongest synergies were between the crop production and the livestock production, and both responded strongly to the cropland and the population density. Trade-offs were identified between provisioning services and soil conservation. Municipalities were grouped into three ESBs in the YRB. The ESB, which was dominated by provisioning ESs, was associated with areas where cropland, precipitation and socioeconomic conditions were all important, and the regulation of ESB was linked to regions with distinct ecological characteristics. We also identified an ESB that was dominated by carbon sequestration, as determined by extensive grassland and bare land. The land use/land cover strongly affected the characteristics of the ESBs. The findings can be used by land managers to identify areas in which ESs are dominant, to determine the associations of these compositions of the ESs with SEVs, and to support the formulation of optimal ES management in large-scale basins.
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•The synergies between ESs substantially exceeded the trade-offs.•Trade-offs occurred between provisioning services and soil conservation.•Three bundles were identified, distinct differentiation in the groupings of ESs.•Land use/land cover strongly affected the characteristics of the ES bundles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A wide area quantum key distribution (QKD) network deployed on communication infrastructures provided by China Mobile Ltd. is demonstrated. Three cities and two metropolitan area QKD networks were ...linked up to form the Hefei-Chaohu-Wuhu wide area QKD network with over 150 kilometers coverage area, in which Hefei metropolitan area QKD network was a typical full-mesh core network to offer all-to-all interconnections, and Wuhu metropolitan area QKD network was a representative quantum access network with point-to-multipoint configuration. The whole wide area QKD network ran for more than 5000 hours, from 21 December 2011 to 19 July 2012, and part of the network stopped until last December. To adapt to the complex and volatile field environment, the Faraday-Michelson QKD system with several stability measures was adopted when we designed QKD devices. Through standardized design of QKD devices, resolution of symmetry problem of QKD devices, and seamless switching in dynamic QKD network, we realized the effective integration between point-to-point QKD techniques and networking schemes.
The design and synthesis of novel two‐dimensional (2D) materials that possess robust structural stability and unusual physical properties may open up enormous opportunities for device and engineering ...applications. Herein, a 2D sumanene lattice that can be regarded as a derivative of the conventional Kagome lattice is proposed. The tight‐binding analysis demonstrates sumanene lattice contains two sets of Dirac cones and two sets of flat bands near the Fermi surface, distinctively different from the Kagome lattice. Using first‐principles calculations, two possible routines for the realization of stable 2D sumanene monolayers (named α phase and β phase) are theoretically suggested, and an α‐sumanene monolayer can be experimentally synthesized with chemical vapor deposition using C21H12 as a precursor. Small binding energies on Au(111) surface (e.g., −37.86 eV Å−2 for α phase) signify the possibility of their peel‐off after growing on the noble metal substrate. Importantly, the GW plus Bethe–Salpeter equation calculations demonstrate both monolayers have moderate band gaps (1.94 eV for α) and ultrahigh carrier mobilities (3.4 × 104 cm2 V−1 s−1 for α). In particular, the α‐sumanene monolayer possesses a strong exciton binding energy of 0.73 eV, suggesting potential applications in optics.
A stable sumanene monolayer of pure carbon is designed that adopts the novel Kagome‐analogy lattice, whose electronic structure contains two sets of Dirac cones and two sets of flat bands near the Fermi surface. The sumanene monolayer possesses ideal band gaps and remarkably high carrier mobility at the same time, as well as exhibits a strong exciton binding energy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Adiabatic quantum control is a very important approach for quantum physics and quantum information processing (QIP). It holds the advantage with robustness to experimental imperfections but ...accumulates more decoherence due to the long evolution time. Here, we propose a universal protocol for fast and robust quantum control in multimode interactions of a quantum system by using shortcuts to adiabaticity. The results show this protocol can speed up the evolution of a multimode quantum system effectively, and it can also keep the robustness very good while adiabatic quantum control processes cannot. We apply this protocol for the quantum state transfer in QIP in the photon-phonon interactions in an optomechanical system, showing a perfect result. These good features make this protocol have the capability of improving effectively the feasibility of the practical applications of multimode interactions in QIP in experiment.
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