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Hydrogen (H) spillover in nonreducible oxides such as zeolites and Al2O3 has been a highly controversial phenomenon in heterogeneous catalysis. Since industrial catalysts are predominantly prepared using these materials as supports, it is important to understand the mechanism and catalytic functions of H spillover on their surfaces. In the past decade, fundamental studies on zeolite-encapsulated metal catalysts have revealed that H spillover and reverse spillover can be utilized in the design of hydrogenation and dehydrogenation catalysts with improved properties. Both experimental and theoretical studies have indicated that H spillover can occur in nonreducible oxides when they possess substantial acid sites that aid the surface migration of active H. In the present review, we will discuss the possible mechanisms of H spillover in nonreducible oxides and the unique opportunities of using this phenomenon for the design of advanced hydroprocessing catalysts. [ABSTRACT FROM AUTHOR]

An increasing number of patients are suffering from central nervous system (CNS) injury, including spinal cord injury. However, no suitable treatment is available for such patients as yet. Various platforms have been utilized to recapitulate CNS injuries. However, animal models and in vitro two-dimensional (2D)-based cell culture platforms have limitations, such as genetic heterogeneity and loss of the neural-circuit ultrastructure. To overcome these limitations, we developed a method for performing axotomy on an open-access three-dimensional (3D) neuron-culture platform. In this platform, the 3D alignment of axons in the brain tissue was recapitulated. For direct access to the cultured axons, the bottom of the 3D neuron-culture device was disassembled, enabling exposure of the neuron-laden Matrigel to the outside. The mechanical damage to the axons was recapitulated by puncturing the neuron-laden Matrigel using a pin. Thus, precise axotomy of three-dimensionally aligned axons could be performed. Furthermore, it was possible to fill the punctuated area by re-injecting Matrigel. Consequently, neurites regenerated into re-injected Matrigel. Moreover, it was confirmed that astrocytes can be co-cultured on this open-access platform without interfering with the axon alignment. The proposed open-access platform is expected to be useful for developing treatment techniques for CNS injuries. [ABSTRACT FROM AUTHOR]

Navigation of nanoparticles to target sites of blood flow disturbance markedly upgrades the diagnostic paradigm in vascular medicine. The theranostic treatment of pre‐stenotic vessels can prevent the irreversible occlusion process effectively. Here, these nanotheranostic functions are established by displaying CDK9(cyclin‐dependent kinase 9)‐targeting peptide (P.) onto nanovesicles (NV) and liposomes using the navigation function and subsequent binding‐on signaling of P. as a game‐changer. When rabbit vessels are allografted with injecting contrast‐loaded P. liposomes, the case‐dependent stenotic degree after 2–6 weeks can be diagnosed accurately within 2–4 days via computed tomography imaging with cross‐validation in a mouse model of partial carotid ligation. Furthermore, the anti‐CDK9 signaling of P. NV is activated post‐targeting and effectively prevents vascular stenosis by suppressing inflammation and lipotoxicity in the vessels, serum, and/or liver. CDK9 targeting is confirmed using computer, in vitro, and in vivo models. This study demonstrates an unprecedented nanotheranostic function for future clinical applications. [ABSTRACT FROM AUTHOR]

Nucleic acid amplification is a widely used diagnostic tool, although it requires a relatively time-consuming and complicated extraction step. To address this issue outside the laboratory, we investigated a sample preparation system and determined that a silica membrane and silica-coated beads are powerful tools for the extraction from raw samples: nucleic acids are kept in the silica membrane, retained during a single wash step, and released at the elution step. The eluent is appropriate for the quantitative real-time polymerase chain reaction (qPCR) and loop-mediated amplification (LAMP) assay in terms of purity and quantity. We also built an innovative equipment-free nucleic acid extraction squeeze system which requires less than 20 min. The sample with improved purity augments the specificity and sensitivity. This system is simple, user-friendly, low-cost, and equipment-free, thus making nucleic acid extraction more accessible and affordable for researchers and untrained users. Furthermore, when combined with the reverse-transcription quantitative real-time polymerase chain reaction method, the method will accelerate the detection of diseases. The same goes when combined with the LAMP assay, especially in developing countries. [ABSTRACT FROM AUTHOR]

Controlling metal–support interactions is important for tuning the catalytic properties of supported metal catalysts. Here, premade Pd particles are supported on stable polymers containing different ligating functionalities to control the metal–polymer interactions and their catalytic properties in industrially relevant acetylene partial hydrogenation. The polymers containing strongly ligating groups (e.g. Ar‐SH and Ar‐S‐Ar) can form a polymer overlayer on the Pd surface, which enables selective acetylene adsorption and partial hydrogenation to ethylene without deactivation. In contrast, polymers with weakly ligating groups (e.g. Ar‐O‐Ar) do not form an overlayer, resulting in non‐selective hydrogenation and fast deactivation, similar to Pd catalysts on conventional inorganic supports. The results imply that tuning the metal–polymer interactions via rational polymer design can provide an efficient way of synthesizing selective and stable catalysts for hydrogenation. [ABSTRACT FROM AUTHOR]

Controlling metal–support interactions is important for tuning the catalytic properties of supported metal catalysts. Here, premade Pd particles are supported on stable polymers containing different ligating functionalities to control the metal–polymer interactions and their catalytic properties in industrially relevant acetylene partial hydrogenation. The polymers containing strongly ligating groups (e.g. Ar‐SH and Ar‐S‐Ar) can form a polymer overlayer on the Pd surface, which enables selective acetylene adsorption and partial hydrogenation to ethylene without deactivation. In contrast, polymers with weakly ligating groups (e.g. Ar‐O‐Ar) do not form an overlayer, resulting in non‐selective hydrogenation and fast deactivation, similar to Pd catalysts on conventional inorganic supports. The results imply that tuning the metal–polymer interactions via rational polymer design can provide an efficient way of synthesizing selective and stable catalysts for hydrogenation. [ABSTRACT FROM AUTHOR]

Controlled decationization (ion exchange with NH4+ and subsequent calcination) of NaX zeolite could produce hierarchically micro-/mesoporous aluminosilicates with systematically variable micro- and mesoporosity. As the Na/Al ratio was decreased from 1 to 0.5, secondary mesoporosity gradually increased up to 0.18 mL g−1 at the cost of initial microporosity while maintaining the total pore volume (＞0.41 mL g−1) and BET surface area (＞630 m2 g−1). On excessive decationization (Na/Al ＜ 0.5), there was no more increase in the mesopore volume, but the microporosity and zeolite crystallinity decreased further. As a result, the fully decationized sample exhibited a solely mesoporous structure but still had a considerable BET surface area (328 m2 g−1). TEM and N2 adsorption–desorption isotherms showed that mesopores were evenly distributed over the entire domain of zeolite crystallites. In contrast, conventional dealumination methods using chemical leaching with HCl and Na2H2EDTA showed heterogeneous destruction of zeolite crystallites: the external rim of the crystallites was heavily damaged to form amorphous mesoporous silicates, but the core of the zeolite crystallite remained intact and solely microporous. The present decationization method provides an extremely economic and simple synthesis route to obtain mesoporous and hierarchically micro-/mesoporous aluminosilicates, which are promising as adsorbents and heterogeneous catalysts for large molecular species. [ABSTRACT FROM AUTHOR]

Nanotheranostics of Pre-Stenotic Vessels By Target Touch-On Signaling of Peptide Navigator (Adv. Funct. CDK9, disturbed flow, nanotheranostics, pre-stenotic vessel, targeting peptide The display of disturbed flow-sensing peptides on nanoparticles enables accurate prediction of pre-stenotic vessels with subsequent prevention of vascular remodeling through multi-organ targeting. [Extracted from the article]