Enhanced Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over Silica-Coated Pt-CoxOy Hybrid Nanoparticles.

Selective hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) is difficult due to the intrinsic difficulty with thermodynamically easier hydrogenation of C═C bonds. In this work, Pt-CoxOy hybrid nanoparticles encapsulated in mesoporous silica nanospheres (Pt-CoxOy@mSiO2) were synthesized by a sol-gel method, which showed greatly improved COL selectivity for hydrogenation of CAL. At 80 °C and 1.0 MPa of H2, Pt-CoxOy@mSiO2 achieved a CAL conversion of 98.7% with a COL selectivity of 93.5%. In contrast, Pt@mSiO2 yields 3-phenylpropanol (HCOL) as the major product with HCOL selectivity of 67.2%, while PtCo@mSiO2 yields 3-phenylpropionaldehyde with selectivity of 51.8% under the same conditions. The enhanced catalytic performance of Pt-CoxOy@mSiO2 for hydrogenation of CAL to COL is ascribed to the Pt surface electron deficiency induced by metal-oxide interaction, and the protection of active NPs by silica shells results in good catalytic stability.

Urolithin A alleviates neuropathic pain and activates mitophagy.

Neuropathic pain (NP) occurs frequently in the general population and has a negative impact on the quality of life. There is no effective therapy available yet owing to the complex pathophysiology of NP. In our previous study, we found that urolithin A (UA), a naturally occurring microflora-derived metabolite, could relieve NP in mice by inhibiting the activation of microglia and release of inflammation factors. Here in this study, we sought to investigate whether mitophagy would be activated when UA alleviated NP in mice. We showed that the autophagy flow was blocked in the spinal dorsal horn of the chronic constriction injury (CCI) mice when the most obvious pain behavior occurs. Intraperitoneal injection of UA markedly activated the mitophagy mediated by PTEN-induced kinase 1/Parkin, promoted mitobiogenesis in both neurons and microglia, and alleviated NP in the CCI mice. In summary, our data suggest that UA alleviates NP in mice and meanwhile induces mitophagy activation, which highlights a therapeutic potential of UA in the treatment of NP.

Synthesis of Mesoporous Silica-Supported NiCo Bimetallic Nanocatalysts and Their Enhanced Catalytic Hydrogenation Performance.

In this work, mesoporous silica SBA-16-supported NiCo bimetallic nanocatalysts were synthesized by coimpregnation of Ni and Co precursors followed by calcination and reduction, and various characterization techniques confirm the formation of NiCo bimetallic nanostructures in the catalysts. The synthesized NiCo/SBA-16 shows enhanced catalytic performance for hydrogenation of a series of nitroaromatics. Under the reaction conditions of 80 °C and 1.0 MPa of H2, the yields of aniline for nitrobenzene hydrogenation over NiCo0.3/SBA-16 can reach more than 99% at 2.0 h. The enhanced catalytic performance can be ascribed to the formation of NiCo bimetallic nanostructures, where the synergistic effect between Ni and Co improves their catalytic activities for hydrogenation of nitroaromatics.

Enhanced Alkene Selectivity for Transfer Semihydrogenation of Alkynes over Electron-Deficient Pt Nanoparticles Encapsulated in Hollow Silica Nanospheres.

In this work, we report that Pt nanoparticles confined in hollow porous silica nanospheres (Pt@HPSNs) function as highly selective catalysts for the transfer hydrogenation of phenylacetylene to styrene with ammonia borane. Relative to the deep hydrogenation of phenylacetylene to ethylbenzene over the supported Pt/SiO2, Pt@HPSNs exhibit above 88% of styrene selectivity at nearly 100% of phenylacetylene conversions, and the high selectivity of Pt@HPSNs can be maintained even at high ammonia borane/phenylacetylene ratios and longer reaction time. The Pt 4f X-ray photoelectron spectrum of Pt@HPSNs shows a remarkable ∼1.5 eV shift to high binding energy, proving the nature of electron deficiency of such encapsulated Pt nanoparticles. Combined with extremely minor transfer hydrogenation of styrene to ethylbenzene when styrene as substrates, the enhanced styrene selectivity of Pt@HPSNs is ascribed to the electron deficiency of encapsulated Pt nanoparticles, which leads to the fast desorption of styrene and thus avoids deep hydrogenation.

Microglial P2Y12 Signaling Contributes to Cisplatin-induced Pain Hypersensitivity via IL-18-mediated Central Sensitization in the Spinal Cord.

Administration of cisplatin and other chemotherapy drugs is crucial for treating tumors. However, cisplatin-induced pain hypersensitivity is still a critical clinical issue, and the underlying molecular mechanisms have remained unresolved to date. In this study, we found that repeated cisplatin treatments remarkedly upregulated the P2Y12 expression in the spinal cord. Expression of P2Y12 was predominant in the microglia. Pharmacological inhibition of P2Y12 expression markedly attenuated the cisplatin-induced pain hypersensitivity. Meanwhile, blocking the P2Y12 signal also suppressed cisplatin-induced microglia hyperactivity. Furthermore, the microglia Src family kinase/p38 pathway is required for P2Y12-mediated cisplatin-induced pain hypersensitivity via the proinflammatory cytokine IL-18 production in the spinal cord. Blocking the P2Y12/IL-18 signaling pathway reversed cisplatin-induced pain hypersensitivity, as well as activation of N-methyl-D-aspartate receptor and subsequent Ca2+-dependent signals. Collectively, our data suggest that microglia P2Y12-SFK-p38 signaling contributes to cisplatin-induced pain hypersensitivity via IL-18-mediated central sensitization in the spinal, and P2Y12 could be a potential target for intervention to prevent chemotherapy-induced pain hypersensitivity. PERSPECTIVE: Our work identified that P2Y12/IL-18 played a critical role in cisplatin-induced pain hypersensitivity. This work suggests that P2Y12/IL-18 signaling may be a useful strategy for the treatment of chemotherapy-induced pain hypersensitivity.

Synthesis of Pd-CoxOy Hybrid Nanostructure-Encapsulated Hollow Silica Nanospheres through Reverse Microemulsion Systems and Their Application as Efficient Hydrodechlorination Catalysts.

Pd-CoxOy heteroaggregate-encapsulated hollow porous silica nanoreactors (Pd-CoxOy@HPSNs) were synthesized by a reverse microemulsion system. The key design of the developed reverse microemulsion system is to use poly(ethyleneimine) in the water droplets as the void templates for silica deposition and for anchoring the catalytic functionality inside the hollow silica nanospheres. The synthesized Pd-CoxOy@HPSNs contain ∼3 nm Pd-CoxOy hybrid nanostructures in ∼10 nm central cavities of silica nanospheres and illustrated a significantly promoted efficiency for hydrodechlorination of a series of chlorophenols into phenols under mild reaction conditions. The catalytic enhancement of Pd-CoxOy@HPSNs is ascribed to the synergistic effect between Pd and CoxOy and the protection of silica shells to the inner catalytic functionality.

Testing Real Quantum Theory in an Optical Quantum Network.

Quantum theory is commonly formulated in complex Hilbert spaces. However, the question of whether complex numbers need to be given a fundamental role in the theory has been debated since its pioneering days. Recently it has been shown that tests in the spirit of a Bell inequality can reveal quantum predictions in entanglement swapping scenarios that cannot be modeled by the natural real-number analog of standard quantum theory. Here, we tailor such tests for implementation in state-of-the-art photonic systems. We experimentally demonstrate quantum correlations in a network of three parties and two independent EPR sources that violate the constraints of real quantum theory by over 4.5 standard deviations, hence disproving real quantum theory as a universal physical theory.

Synthesis of Hollow Silica Nanotubes from Linear Metallosupramolecular Polyelectrolytes and Their Application as Catalyst Supports for Hydrogenation.

In this study, we report a facile templating method to construct hollow silica nanotubes. In particular, bis-terpyridine is used to coordinate metal ions to form polymeric bis-terpyridine-metal complexes that further self-assemble into tubular organogels in the presence of cetyltrimethylammonium bromide. The following silica deposition on organogels and subsequent calcination give metal oxide-doped hollow silica nanotubes (MxOy-HSNs). Facilitated by the high coordination stability constants of bis-terpyridine with metal ions, a series of metal ions, such as Fe, Ni, Cu, and Zn, could be used to form polymeric bis-terpyridine-metal complexes. The supported Pt/FexOy-HSNs exhibit good catalytic performance for hydrogenation of a series of substituted nitrobenzenes, showing that the obtained MxOy-HSNs could be used as catalyst supports due to their good textural properties.

Optimized Detection of High-Dimensional Entanglement.

Entanglement detection is one of the most conventional tasks in quantum information processing. While most experimental demonstrations of high-dimensional entanglement rely on fidelity-based witnesses, these are powerless to detect entanglement within a large class of entangled quantum states, the so-called unfaithful states. In this Letter, we introduce a highly flexible automated method to construct optimal tests for entanglement detection given a bipartite target state of arbitrary dimension, faithful or unfaithful, and a set of local measurement operators. By restricting the number or complexity of the considered measurement settings, our method outputs the most convenient protocol which can be implemented using a wide range of experimental techniques such as photons, superconducting qudits, cold atoms, or trapped ions. With an experimental quantum optics setup that can prepare and measure arbitrary high-dimensional mixed states, we implement some three-setting protocols generated by our method. These protocols allow us to experimentally certify two- and three-unfaithful entanglement in four-dimensional photonic states, some of which contain well above 50% of noise.

Preparation of aligned nanofibers using parallel inductive-plates assisted electrospinning.

Electrospinning is a simple, cost-effective, and versatile technique for fabrication of nanofibers. However, nanofibers obtained from the conventional electrospinning are typically disordered, which seriously limits their application. In this work, we present a novel and facile technique to obtain aligned nanofibers with high efficiency by using parallel inductive-plates assisted electrospinning (PIES). In this new electrospinning setup, the electrostatic spinneret is contained in a pair of parallel inductive-plates, which can change the shape and direction of the electric field line during the electrospinning so as to control the flight trajectory and spatial alignment of the spinning nanofibers. This electrospinning setup can divide the electric field line into two parts which are respectively directed to the edge of the upper and lower inductive-plates. Then the nanofibers move along the electric field line, suspend and align between the parallel inductive-plates. Finally, the well aligned nanofibers could be easily transferred onto other substrates for further characterizations and applications. The aligned nanofibers with an average diameter of 469 ± 115 nm and a length as long as 140 mm were successfully achieved by using PIES technique. Moreover, nanofiber arrays with different cross angles and three-dimensional films formed by the aligned nanofibers were also facilely obtained. The novel PIES developed in this work has been proved to be a facile, cost-effective and promising approach to prepare aligned nanofibers for a wide range of applications.

Microtip focused electrohydrodynamic jet printing with nanoscale resolution.

Electrohydrodynamic jet (E-Jet) printing is a promising manufacturing technique for micro-/nano-patterned structures with high resolution, high efficiency and high material compatibility. However, further improvement of the necking ratio of the E-Jet is still limited by the focusing principle. Moreover, ink viscosity is limited to values well below 90 mPa s owing to the high probability of nozzle blockage. Here, we propose a microtip focused electrohydrodynamic jet (MFEJ) printing to overcome these limitations. This technique uses a solid microtip with a radius of curvature (ROC) of several micrometers rather than a hollow nozzle, which is very simple and highly efficient to prepare and can effectively avoid nozzle clogging problems even with high-viscosity printing ink. High-resolution patterns in diverse geometries were printed using different inks with a wide range of viscosities (8.4-3500 mPa s). Nanodroplets with an average diameter of 73 nm were achieved. Moreover, nanofibers with a diameter of 30 nm were obtained using a 4 µm ROC microtip and the necking ratio was as high as 266 : 1. To the best of our knowledge, this is the smallest droplet or fiber diameter directly obtained via E-Jet printing to date without further physical or chemical processing. This MFEJ printing technique can improve printing resolution at the nanoscale, significantly enlarge the material applicability and effectively avoid nozzle clogging for the fabrication of nanodevices.

Controllable Synthesis of Surface Pt-Rich Bimetallic AuPt Nanocatalysts for Selective Hydrogenation Reactions.

Bimetallic nanocatalysts, with efficient and controllable catalytic performance, have a promising application in chemical production. In this study, surface Pt-rich bimetallic AuPt nanoparticles with different Pt/Au ratios were prepared and tested in selective hydrogenation reactions of substituted nitroaromatics. Au nanoparticles were first prepared with n-butyllithium as a rapid reducer, which were further used as seeds in the slow growth process of Pt atoms. Because of the employed sequential reduction method and the following atom diffusion, surface Pt-rich bimetallic AuPt nanoparticles were obtained. Compared with the uniform AuPt alloy nanocatalysts synthesized by the co-reduction method with n-butyllithium as the reducer and monometallic Pt nanocatalysts, the obtained surface Pt-rich AuPt bimetallic nanocatalysts presented an enhanced catalytic selectivity or activity. The performance enhancement is assigned to the optimized Au/Pt interaction in the surface Pt-rich bimetallic nanostructures. This work demonstrates that the optimization of the stoichiometry and construction of bimetallic materials is a feasible method to synthesize controllable and efficient nanocatalysts.

Two-dimensional translation-invariant probability distributions: approximations, characterizations and no-go theorems.

We study the properties of the set of marginal distributions of infinite translation-invariant systems in the two-dimensional square lattice. In cases where the local variables can only take a small number d of possible values, we completely solve the marginal or membership problem for nearest-neighbours distributions (d = 2, 3) and nearest and next-to-nearest neighbours distributions (d = 2). Remarkably, all these sets form convex polytopes in probability space. This allows us to devise an algorithm to compute the minimum energy per site of any TI Hamiltonian in these scenarios exactly. We also devise a simple algorithm to approximate the minimum energy per site up to arbitrary accuracy for the cases not covered above. For variables of a higher (but finite) dimensionality, we prove two no-go results. To begin, the exact computation of the energy per site of arbitrary TI Hamiltonians with only nearest-neighbour interactions is an undecidable problem. In addition, in scenarios with d≥2947, the boundary of the set of nearest-neighbour marginal distributions contains both flat and smoothly curved surfaces and the set itself is not semi-algebraic. This implies, in particular, that it cannot be characterized via semidefinite programming, even if we allow the input of the programme to include polynomials of nearest-neighbour probabilities.

Entanglement and Nonlocality in Infinite 1D Systems.

We consider the problem of detecting entanglement and nonlocality in one-dimensional (1D) infinite, translation-invariant (TI) systems when just near-neighbor information is available. This issue is deeper than one might think a priori, since, as we show, there exist instances of local separable states (classical boxes) which admit only entangled (nonclassical) TI extensions. We provide a simple characterization of the set of local states of multiseparable TI spin chains and construct a family of linear witnesses which can detect entanglement in infinite TI states from the nearest-neighbor reduced density matrix. Similarly, we prove that the set of classical TI boxes forms a polytope and devise a general procedure to generate all Bell inequalities which characterize it. Using an algorithm based on matrix product states, we show how some of them can be violated by distant parties conducting identical measurements on an infinite TI quantum state. All our results can be easily adapted to detect entanglement and nonlocality in large (finite, not TI) 1D condensed matter systems.

Nonlocality of symmetric states.

In this Letter we study the nonlocal properties of permutation symmetric states of n qubits. We show that all these states are nonlocal, via an extended version of the Hardy paradox and associated inequalities. Natural extensions of both the paradoxes and the inequalities are developed which relate different entanglement classes to different nonlocal features. Belonging to a given entanglement class will guarantee the violation of associated Bell inequalities which see the persistence of correlations to subsets of players, whereas there are states outside that class which do not violate.