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2D functional porous frameworks offer a platform for studying the structure–activity relationships during electrocatalytic CO2 reduction reaction (CO2RR). Yet challenges still exist to breakthrough key limitations on site configuration (typical M−O4 or M−N4 units) and product selectivity (common CO2‐to‐CO conversion). Herein, a novel 2D metal–organic framework (MOF) with planar asymmetric N/O mixed coordinated Cu−N1O3 unit is constructed, labeled as BIT‐119. When applied to CO2RR, BIT‐119 could reach a CO2‐to‐C2 conversion with C2 partial current density ranging from 36.9 to 165.0 mA cm−2 in flow cell. Compared to the typical symmetric Cu−O4 units, asymmetric Cu−N1O3 units lead to the re‐distribution of local electron structure, regulating the adsorption strength of several key adsorbates and the following catalytic selectivity. From experimental and theoretical analyses, Cu−N1O3 sites could simultaneously couple the atop‐type (on Cu site) and bridge‐type (on Cu−N site) adsorption of *C1 species to reach the CO2‐to‐C2 conversion. This work broadens the feasible C−C coupling mechanism on 2D functional porous frameworks. [ABSTRACT FROM AUTHOR]

In this report, we developed an efficient one-pot method for the synthesis of 3-phenyl-1-(phenylthio)imidazo[1,5-a]pyridine analogs starting from 2-aminomethylpyridines, benzaldehydes, and sodium benzenesulfinates, which constructed C-N and C-S bonds simultaneously. The method features mild reaction conditions, a wide range of substrates, high atom utilization, and convenient and easily accessible starting materials. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 to multi‐carbon products is an attractive strategy to achieve a carbon‐neutral energy cycle. Single‐atom catalysts (SACs) that achieve the C2 selectivity always have low metal loading and inevitably undergo in situ reversible/irreversible metallic agglomerations under working conditions. Herein, a high‐density Cu SA anchored F, O, N co‐doped carbon composites (CuFONC) with a stable CuN2O1 configuration is provided, which can reach a remarkable C2 selectivity of ≈80.5% in Faradaic efficiency at −1.3 V versus RHE. In situ/ex situ experimental characterization and density functional theory (DFT) calculations verified that the excellent stability of CuN2O1 during the CO2RR process can be attributed to F/O co‐derived regulation for CuFONC. Remarkably, as confirmed by DFT, it is atomic Cu sites and the adjacent bonded N motifs in CuFONC that act as the adsorption sites for CO* during the C─C coupling process. This work brings a prospective on designing novel but stable atomic Cu coordination for electrolytic CO2‐to‐C2 pathway. [ABSTRACT FROM AUTHOR]

Single atomic catalysts (SACs) offer a superior platform for studying the structure–activity relationships during electrocatalytic CO2 reduction reaction (CO2RR). Yet challenges still exist to obtain well‐defined and novel site configuration owing to the uncertainty of functional framework‐derived SACs through calcination. Herein, a novel Bi−N2O2 site supported on the (1 1 0) plane of hydrogen‐bonded organic framework (HOF) is reported directly for CO2RR. In flow cell, the target catalyst Bi1‐HOF maintains a faradaic efficiency (FE) HCOOH of over 90 % at a wide potential window of 1.4 V. The corresponding partial current density ranges from 113.3 to 747.0 mA cm−2. And, Bi1‐HOF exhibits a long‐term stability of over 30 h under a successive potential‐step test with a current density of 100–400 mA cm−2. Density function theory (DFT) calculations illustrate that the novel Bi−N2O2 site supported on the (1 1 0) plane of HOF effectively induces the oriented electron transfer from Bi center to CO2 molecule, reaching an enhanced CO2 activation and reduction. Besides, this study offers a versatile method to reach series of M−N2O2 sites with regulable metal centers via the same intercalation mechanism, broadening the platform for studying the structure–activity relationships during CO2RR. [ABSTRACT FROM AUTHOR]

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) following chemotherapy is part of standard treatment protocol for patients with acute myeloid leukemia (AML). FUS-ERG+ AML is rare but has an extremely poor prognosis even with allo-HSCT in remission, possibly due to its a leukemia stem cell (LSC)-driven disease resulting in chemotherapy resistance and a novel therapy is urgently required. It has been reported that FUS-ERG-positive AML expresses CD123, a marker of LSC, in some cases. CD123-targeted CAR T cell (CART123) is promising immunotherapy, but how to improve the complete remission (CR) rate and rescue potential hematopoietic toxicity still need to explore.Case Presentation: We used donor-derived CART123 as part of conditioning regimen for haploidentical HSCT (haplo-HSCT) in a patient with FUS-ERG+ AML who relapsed after allogeneic transplantation within 3 months, resists to multi-agent chemotherapy and donor lymphocyte infusion (DLI) and remained non-remission, aiming to reduce these chemotherapy-resistant blasts and rescue potential hematopoietic toxicity. The blasts in BM were reduced within 2 weeks and coincided with CAR copies expansion after CART123 infusion. The patient achieved full donor chimerism, CR with incomplete blood count recovery, and myeloid implantation.Conclusion: Our results hints that CART123 reduces the chemotherapy-resistant AML blasts for FUS-ERG+ AML without affecting the full donor chimerism and myeloid implantation.

In this paper, we consider the existence and uniqueness of mild solutions for stochastic nonlocal evolution equations with Lévy diffusion operator and nonlocal initial conditions. Based on the continuity of the Lévy semigroup and the technique of the measure of noncompactness, we establish the local existence of mild solutions in C 0 , T ; L q (Ω ; L q (ℝ N)) under some weaker growth conditions. Moreover, we obtain the existence of mild solutions on any finite interval by using the general growth conditions on the nonlinear. Finally, the global existence and uniqueness of mild solutions follow from the additional Lipschitz conditions on nonlinear terms. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a chronic inflammatory disease leading to various vascular diseases. Vascular smooth muscle cell (VSMC) senescence promotes atherosclerotic inflammation and the formation of plaque necrosis core, in part through telomere damage mediated by a high-fat diet. Our previous research found that paeonol, a potential anti-inflammatory agent extracted from Cortex Moutan, could significantly improve VSMCs dysfunction. However, the impact of paeonol on the senescence of VSMCs remains unexplored. This study presents the protective effects of paeonol on VSMCs senescence, and its potential activity in inhibiting the progression of atherosclerosis in vivo and in vitro. Sirtuin 1 (SIRT1) is a nuclear deacetylase involved in cell proliferation, senescence, telomere damage, and inflammation. Here, SIRT1 was identified as a potential target of paeonol having anti-senescence and anti-atherosclerosis activity. Mechanistic studies revealed that paeonol binds directly to SIRT1 and then activates the SIRT1/P53/TRF2 pathway to inhibit VSMCs senescence. Our results suggested that SIRT1-mediated VSMCs senescence is a promising druggable target for atherosclerosis, and that pharmacological modulation of the SIRT1/P53/TRF2 signaling pathway by paeonol is of potential benefit for patients with atherosclerosis. [ABSTRACT FROM AUTHOR]

Precisely designing asymmetric diatomic configurations and studying their electronic regulation effect for improving the oxygen reduction reaction (ORR) performance are important for anion exchange membrane fuel cells (AEMFCs). Here, a Fe, Cu co‐doped 2D crystalline IISERP‐MOF27 nanosheet derived FeN3O‐CuN4 diatomic site nanocatalyst (named as FeCu‐NC) is synthesized for the cathodes of AEMFCs. Thanks to the optimal electronic structure of FeN3O‐CuN4 in the FeCu‐NC catalyst, it shows enhanced half‐wave potential (0.910 V), turnover frequency (0.165e s−1 site−1), and decreased activation energy (19.96 kJ mol−1) in KOH. The FeCu‐NC‐based AEMFC achieves extremely high kinetic current (0.138 A cm−2 at 0.9 V) and rated power density (1.09 W cm−2), surpassing the best‐reported transition metal‐based cathodes. Density functional theory calculations further demonstrate that the Cu‐N4 can break the localization of Fe‐3d orbitals, accelerate the electron transport, and optimize the OH adsorption, thus facilitating the ORR process. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) have been regarded as an effective means to transform hydrogen energy into electric energy, which is featured with high energy density, excellent conversion efficiency, and environmental friendliness. Carbon nanomaterials are the most widely used supports for the state-of-the-art Pt-based PEMFC cathode catalysts. Nonetheless, the corrosion of carbon supports under high potential environment would inevitably lead to the dissolution/ripening of Pt, resulting in the severe degradation of their PEMFC performance. Carbon-free materials, such as transition metal oxides/nitrides/sulfides/carbides (TMOs, TMNs, TMSs, and TMCs), can effectively prevent this issue with their excellent intrinsic stability and tuned metal–support interactions (MSI). Recently, numerous researches have been focused on the design and preparation of carbon-free PEMFC cathode catalysts. Meanwhile, MSI effect, including d-band center, migration energy barrier, defect sites, coordination environment, and electron transfer ability, have also been considered to improve the PEMFCs performance. In this review, the MSI effect of carbon-free PEMFC cathode materials and their common adjustment strategies are systematically summarized. Then, details about the pristine and modified carbon-free PEMFC catalysts and their specific structure–activity relationships induced by MSI effect are further illustrated in the order of TMOs, TMCs, TMNs, and TMSs. Finally, the challenges and perspectives of carbon-free PEMFC cathode catalysts are further proposed to provide insights into future researches in this PEMFC field. [ABSTRACT FROM AUTHOR]

Developing highly efficient and stable hydrogen production catalysts for electrochemical water splitting (EWS) at industrial current densities remains a great challenge. Herein, we proposed a heterostructure‐induced‐strategy to optimize the metal‐support interaction (MSI) and the EWS activity of Ru‐Ni3N/NiO. Density functional theory (DFT) calculations firstly predicted that the Ni3N/NiO‐heterostructures can improve the structural stability, electronic distributions, and orbital coupling of Ru‐Ni3N/NiO compared to Ru‐Ni3N and Ru‐NiO, which accordingly decreases energy barriers and increases the electroactivity for EWS. As a proof‐of‐concept, the Ru‐Ni3N/NiO catalyst with a 2D Ni3N/NiO‐heterostructures nanosheet array, uniformly dispersed Ru nanoparticles, and strong MSI, was successfully constructed in the experiment, which exhibited excellent HER and OER activity with overpotentials of 190 mV and 385 mV at 1000 mA cm−2, respectively. Furthermore, the Ru‐Ni3N/NiO‐based EWS device can realize an industrial current density (1000 mA cm−2) at 1.74 V and 1.80 V under alkaline pure water and seawater conditions, respectively. Additionally, it also achieves a high durability of 1000 h (@ 500 mA cm−2) in alkaline pure water. [ABSTRACT FROM AUTHOR]

This paper is concerned with stochastic delay evolution equations driven by tempered fractional Brownian motion (tfBm) $ B_Q^{\sigma, \lambda}(t) $ with time fractional operator of order $ \alpha\in (1/2+\sigma, 1) $, where $ \sigma\in (-1/2, 0) $ and $ \lambda>0 $. First, we establish the global existence and uniqueness of mild solutions by using the new established estimation of stochastic integrals with respect to tfBm. Moreover, based on the relations between the stochastic integrals with respect to tfBm and fBm, we show the continuity of mild solutions for stochastic delay evolution equations when tempered fractional noise is reduced to fractional noise. Finally, we analyze the stability with general decay rate (including exponential, polynomial and logarithmic stability) of mild solutions for stochastic delay evolution equations with tfBm and time tempered fractional operator. [ABSTRACT FROM AUTHOR]

The polynomial stability problem of stochastic delay differential equations has been studied in recent years. In contrast, there are relatively few works on stochastic partial differential equations with pantograph delay. The present paper is devoted to investigating large-time asymptotic properties of solutions for stochastic pantograph delay evolution equations with nonlinear multiplicative noise. We first show that the mild solutions of stochastic pantograph delay evolution equations with nonlinear multiplicative noise tend to zero with general decay rate (including both polynomial and logarithmic rates) in the p th moment and almost sure senses. The analysis is based on the Banach fixed point theorem and various estimates involving the gamma function. Moreover, by using a generalized version of the factorization formula and exploiting an approximation technique and a convergence analysis, we construct the nontrivial equilibrium solution, defined for t ∈ ℝ , for stochastic pantograph delay evolution equations with nonlinear multiplicative noise. In particular, the uniqueness, Hölder regularity in time and general stability, in the p th moment and almost sure senses, of the nontrivial equilibrium solution are established. [ABSTRACT FROM AUTHOR]

The implementation of national educational reform in China calls for newer and stronger school administration. Recognizing the need to establish a knowledge base for leadership development, we employ a set of existing US professional standards for educational leaders as a frame of reference to unpack the complex role of Chinese superintendents. Using data collected from two surveys administered to more than 200 Chinese superintendents in 2007, we find that many indicators of leadership considered essential in the United States are also viewed as necessary for effective superintendency in China. Feedback from the superintendents also points out gaps between what is perceived as important and what is in practice. This article contributes to the efforts of building meaningful global dialogues among researchers and practitioners on developing a new generation of education administrators. (Contains 3 figures, 4 tables, and 6 footnotes.)