Expedient hydroarylations of C=Het bonds (Het=heteroatom) were accomplished by user‐friendly organometallic C−H activation in a positional‐selective manner. The broadly applicable C−H ...functionalization platform enabled the step‐economical transformation of aldehydes, ketones, and imines under additive‐free reaction conditions. In contrast to palladium, rhodium, ruthenium, rhenium, iridium, nickel, and cobalt catalysis, solely manganese(I) complexes outcompeted the innate substrate control, clearly highlighting the unique power of manganese(I) C−H activation catalysis.
One catalyst to rule them all: The unique selectivity of manganese(I) catalysis in heteroarene C−H activation set the stage for positional selective hydroarylations with ample scope under additive‐free conditions, outcompeting palladium, rhodium, ruthenium, rhenium, iridium, nickel, iron, and cobalt catalysts.
Owing to the rapid developments to improve the accuracy and efficiency of both experimental and computational investigative methodologies, the massive amounts of data generated have led the field of ...materials science into the fourth paradigm of data‐driven scientific research. This transition requires the development of authoritative and up‐to‐date frameworks for data‐driven approaches for material innovation. A critical discussion on the current advances in the data‐driven discovery of materials with a focus on frameworks, machine‐learning algorithms, material‐specific databases, descriptors, and targeted applications in the field of inorganic materials is presented. Frameworks for rationalizing data‐driven material innovation are described, and a critical review of essential subdisciplines is presented, including: i) advanced data‐intensive strategies and machine‐learning algorithms; ii) material databases and related tools and platforms for data generation and management; iii) commonly used molecular descriptors used in data‐driven processes. Furthermore, an in‐depth discussion on the broad applications of material innovation, such as energy conversion and storage, environmental decontamination, flexible electronics, optoelectronics, superconductors, metallic glasses, and magnetic materials, is provided. Finally, how these subdisciplines (with insights into the synergy of materials science, computational tools, and mathematics) support data‐driven paradigms is outlined, and the opportunities and challenges in data‐driven material innovation are highlighted.
The recent advances, strategies, insights, and challenges of data‐driven‐based innovations and applications in material science are discussed. Essential subdisciplines, including framework, machine‐learning algorithms, available chemical databases, commonly used key descriptors, and innovations and applications based on their synergy, are reviewed.
Direct functionalization of the benzylic C−H bond of diarylmethanes is an important strategy for the synthesis of diarylmethine‐containing compounds. However, the methods developed to date for this ...purpose require a stoichiometric amount (usually more) of either a strong base or an oxidant. Reported here is the first catalytic benzylic C−H bond addition of diarylmethanes to styrenes and conjugated dienes. A potassium zincate complex, generated from potassium benzyl and zinc amide, acts as a catalyst and displays good activity and chemoselectivity. Considering the atom economy of the reaction and the ready availability of the catalyst, this reaction constitutes a practical, efficient method for diarylalkane synthesis.
‘Zinc' into it: The catalytic addition of the benzylic carbon center of diarylmethanes to styrenes and conjugated dienes was achieved for the first time by using a potassium zincate catalyst. The reaction demonstrates wide scope and high yields.
Heterocyclics are the crucial scaffolds present in pharmaceuticals, natural products, biologically active compounds and agrochemicals. Consequently, the development of simple and practical methods ...for constructing heterocyclics has always been a fascinating field in organic synthesis. Recently, 2‐acylbenzoic acids, highly reactive and versatile synthons, have been broadly applied in the construction of heterocycles due to their multiple reaction sites. In this review, we summarized recent progress in the application of 2‐acylbenzoic acids for the synthesis of heterocycles including phthalides, isochromanones, isoindolines, phthalazinones, and quinolones. The substrate scopes, proposed mechanisms, and product application of different types of reactions are discussed.
Here summarized the recent progress in the application of 2‐acylbenzoic acids for the synthesis of heterocycles including phthalides, isochromanones, isoindolines, phthalazinones, quinolones and their derivatives.
Harnessing the physiochemical properties and enzymatic activities of nanozymes will provide new insights for disease theranostics. Herein, a novel carbon dot (C‐dot) superoxide dismutase (SOD) ...nanozyme that exhibits red fluorescence with emission wavelength of 683 nm and shows high SOD‐like activity of >4000 U mg−1 is reported, which presents the great potential for imaging the biodistribution of nanozyme itself in vivo and ameliorating acute lung injury. Through surface modifications, the mechanism of C‐dot SOD nanozyme activity is revealed to be relied on their surface functional groups which bind with superoxide radicals, promote the electron transfer between C‐dots and superoxide radicals, and finally accelerate the dismutation of superoxide radicals. The absolute quantum yield of ≈14% of red fluorescence C‐dot nanozyme endow it bioimaging in vitro and in vivo. Moreover, the C‐dot nanozyme effectively enters the cells, accumulates at mitochondria, and protects living cells from oxidative damage by scavenging reactive oxygen species (ROS) and reducing the levels of pro‐inflammatory factors. Importantly, in vivo animal experiments demonstrate the accumulation of C‐dots in injure lung and therapeutic effect of C‐dot nanozyme toward acute lung injury in mice. The red fluorescent C‐dot SOD nanozyme shows great potential for in vivo bioimaging and management of ROS‐related diseases.
Red emissive carbon dot nanozyme with high superoxide dismutase (SOD)‐like activity over 4000 U mg−1 is developed. The SOD nanozyme activity is revealed to be relied on their surface functional groups which capture O2•– and then promote the electron transfer between O2•– and π‐system of carbon dot. The C‐dot SOD nanozyme shows great potential in bioimaging and ameliorating acute lung injury.
Modulation of the electronic structure of metal catalysts is an effective approach to optimize the electrocatalytic activity. Herein, we show a surprisingly strong activation effect of black ...phosphorus (BP) on platinum (Pt) catalysts to give greatly enhanced catalytic activity in the hydrogen evolution reaction (HER). The unique and negative binding energy between BP and Pt leads to spontaneous formation of Pt‐P bonds producing strong synergistic ligand effects on the Pt nanoparticles. No Pt‐P bonds are formed with red phosphorus which is another allotrope of P. By controlling the number of Pt‐P bonds, 3.5‐fold enhancement in the HER activity can be achieved from the BP‐activated Pt catalyst and the activity is 6.1 times higher than that of the state‐of‐the‐art commercial Pt/C catalyst. The BP‐activated Pt catalyst exhibits a current density of 82.89 mA cm−2 with only 1 μg of Pt in 1 m KOH at an overpotential of 70 mV.
Back in black: Surprisingly strong activation effects of black phosphorus (BP) on Pt catalysts and subsequent modulation the surface electronic structure of Pt result in greatly enhanced catalytic activity in the hydrogen evolution reaction (HER).
Abstract
Background
The R1441G mutation in the leucine-rich repeat kinase 2 (LRRK2) gene results in late-onset Parkinson’s disease (PD). Peripheral inflammation and gut microbiota are closely ...associated with the pathogenesis of PD. Chronic periodontitis is a common type of peripheral inflammation, which is associated with PD.
Porphyromonas gingivalis
(Pg), the most common bacterium causing chronic periodontitis, can cause alteration of gut microbiota. It is not known whether Pg-induced dysbiosis plays a role in the pathophysiology of PD.
Methods
In this study, live Pg were orally administrated to animals, three times a week for 1 month. Pg-derived lipopolysaccharide (LPS) was used to stimulate mononuclear cells in vitro. The effects of oral Pg administration on the gut and brain were evaluated through behaviors, morphology, and cytokine expression.
Results
Dopaminergic neurons in the substantia nigra were reduced, and activated microglial cells were increased in R1441G mice given oral Pg. In addition, an increase in mRNA expression of tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β) as well as protein level of α-synuclein together with a decrease in zonula occludens-1 (Zo-1) was detected in the colon in Pg-treated R1441G mice. Furthermore, serum interleukin-17A (IL-17A) and brain IL-17 receptor A (IL-17RA) were increased in Pg-treated R1441G mice.
Conclusions
These findings suggest that oral Pg-induced inflammation may play an important role in the pathophysiology of LRRK2-associated PD.
Most contemporary X‐ray detectors adopt device structures with non/low‐gain energy conversion, such that a fairly thick X‐ray photoconductor or scintillator is required to generate sufficient ...X‐ray‐induced charges, and thus numerous merits for thin devices, such as mechanical flexibility and high spatial resolution, have to be compromised. This dilemma is overcome by adopting a new high‐gain device concept of a heterojunction X‐ray phototransistor. In contrast to conventional detectors, X‐ray phototransistors allow both electrical gating and photodoping for effective carrier‐density modulation, leading to high photoconductive gain and low noise. As a result, ultrahigh sensitivities of over 105 μC Gyair−1 cm−2 with low detection limit are achieved by just using an ≈50 nm thin photoconductor. The employment of ultrathin photoconductors also endows the detectors with superior flexibility and high imaging resolution. This concept offers great promise in realizing well‐balanced detection performance, mechanical flexibility, integration, and cost for next‐generation X‐ray detectors.
An ultrathin and ultrasensitive direct X‐ray detector based on a heterojunction phototransistor is developed by taking advantage of high‐gain and gating‐modulation mechanisms. This unique device concept allows for a significant reduction in X‐ray photoconductor thickness while maintaining high sensitivity and low detection limit, which opens up new opportunities for developing high‐resolution, flexible, and low‐cost X‐ray direct detectors.
Radio frequency identification (RFID) has shown its potential in human-machine interaction thanks to its inherent function of identification and relevant physical information of signals, but complex ...data processing and undesirable input accuracy restrict its application and promotion in practical use. This paper proposes a novel finger-controlled passive RFID tag design for human-machine interaction. The tag antenna is based on a dipole antenna with a separated T-match structure, which is able to adjust the state of the tag by the press of a finger. The state of the proposed tag can be recognized directly by the code received by the RFID reader, and no complex data processing is needed. Since the code is hardly affected by surroundings, the proposed tag is suitable to be used as a wireless switch or control button in multiple scenarios. Moreover, arrays of the proposed tag with rational tag arrangements could contribute to a series of manual control devices, such as a wireless keyboard, a remote controller, and a wireless gamepad, without batteries. A 3 × 4 array of the finger-controlled tag is presented to constitute a simple passive RFID keyboard as an example of the applications of the proposed tag array and it refers to the arrangement of a keypad and can achieve precise, convenient, quick, and practical commands and text input into machines by pressing the tags with fingers. Simulations and measurements of the proposed tag and tag array have been carried out to validate their performances in human-machine interaction.
Myeloid-derived suppressor cells (MDSCs) are pathologically activated and relatively immature myeloid cells that have been implicated in the immunological regulation of many pathologic conditions. ...Phenotypically and morphologically, MDSCs are similar to neutrophils (PMN-MDSCs) and monocytes (M-MDSCs). However, they have potent suppressive activity and distinct gene expression profiles and biochemical characteristics. No or very few MDSCs are observed in steady-state physiological conditions. Therefore, until recently, accumulation of MDSCs was considered a consequence of pathological processes or pregnancy. Here, we report that MDSCs with a potent ability to suppress T cells are present during the first weeks of life in mice and humans. MDSC suppressive activity was triggered by lactoferrin and mediated by nitric oxide, PGE2, and S100A9 and S100A8 proteins. MDSCs from newborns had a transcriptome similar to that of tumor MDSCs, but with strong upregulation of an antimicrobial gene network, and had potent antibacterial activity. MDSCs played a critical role in control of experimental necrotizing enterocolitis (NEC) in newborn mice. MDSCs in infants with very low weight, who are prone to NEC, had lower MDSC levels and suppressive activity than did infants with normal weight. Thus, the transitory presence of MDSCs may be critical for regulation of inflammation in newborns.
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