Magnetoelectric materials with a large magnetoelectric response, a low operating magnetic (or electric) field, and a room‐temperature (or higher) operating temperature are of key importance for ...practical applications. However, such materials are extremely rare because a large magnetoelectric response often requires strong coupling between spins and electric dipoles. Herein, an example of a magnetoelectric composite is prepared by using a room‐temperature multiaxial molecular–ionic ferroelectric, tetramethylammonium tetrachlorogallate(III) (1). Investigation of the magnetoelectric effect of the magnetoelectric laminate composite indicates that its room‐temperature magnetoelectric voltage coefficient (αME) is as high as 186 mV cm−1 Oe−1 at HDC = 275 Oe and at the HAC frequency of ≈39 kHz, providing a valid approach for the preparation of magnetoelectric materials and adding a new member to the magnetoelectric material family.
A magnetoelectric composite is prepared by using a room‐temperature multiaxial molecular–ionic tetramethylammonium tetrachlorogallate(III) ferroelectric. The room‐temperature magnetoelectric voltage coefficient is up to 186 mV cm−1 Oe−1 at HDC = 275 Oe and the HAC frequency is ≈39 kHz. This work demonstrates that multiaxial molecular–ionic ferroelectrics are new excellent candidates for the preparation of magnetoelectric composites.
As an important member of group VA–VIA semiconductors, 2D Sb2Se3 has drawn widespread attention thanks to its outstanding optoelectronic properties as compared to the bulk material. However, due to ...the intrinsic chain‐like crystal structure, the controllable synthesis of ultrathin 2D planar Sb2Se3 nanostructures still remains a huge challenge. Herein, for the first time, the crystal structure limitation is overcome and the successful structural evolution of 2D ultrathin Sb2Se3 flakes (as thin as 1.3 nm), by introducing a sodium‐mediated chemical vapor deposition (CVD) growth method, is realized. The formation of 2D planar geometry is mainly attributed to the preferential growth of (010) plane with the lowest formation energy. The thickness‐dependent band structure of 2D Sb2Se3 flakes shows a wide absorption band from UV to NIR region (300–1000 nm), suggesting its potential application in broadband photodetection. Strikingly, the Sb2Se3 flakes–based photodetector demonstrates excellent performance such as broadband response varying from UV to NIR region, high responsivity of 4320 mA W−1, fast response time (τrise ≈ 13.16 ms and τdecay ≈ 9.61 ms), and strong anisotropic ratio of 2.5@ 532 nm, implying promising potential application in optoelectronics.
For the first time, the crystal structure limitation is overcome and the successful structural evolution of 2D ultrathin Sb2Se3 flakes (as thin as 1.3 nm), by introducing a sodium‐mediated chemical vapor deposition growth method, is realized. The Sb2Se3 flakes‐based photodetector shows a broadband photodetection range from the UV to NIR region, due to the high‐quality single‐crystalline character and 2D morphology of Sb2Se3 flakes.
Neuroinflammation is initiated in response to a variety of endogenous and exogenous sources. As the resident macrophages of the central nervous system, the polarization of microglia into either the ...M1 pro-inflammatory phenotype or the M2 anti-inflammatory phenotype holds great promise as a therapeutic strategy for neuroinflammation. Natural products, comprising a vital chemical library with distinctive structures and diverse functions, have been extensively employed to modulate microglial polarization for the treatment of neuroinflammation. In this review, we present up-to-date and extensive insights into the therapeutic effects and underlying mechanisms of natural products in the context of neuroinflammation. Furthermore, the review aims to present a new perspective by focusing on the targets of natural compounds, elucidating the molecular mechanisms and guiding the transition from natural-derived lead compounds to potential anti-neuroinflammatory drugs. Additionally, we provide a comprehensive overview of the challenges and limitations associated with the utilization of natural products for neuroinflammation therapy.
Mercury sulfide (HgS) exerts extensive biological effects on neuronal function. To investigate the direct target of HgS in neuronal cells, we developed a biotin-tagged HgS probe (bio-HgS) and ...employed an affinity purification technique to capture its target proteins. Then, we identified S-phase kinase-associated protein 1 (Skp1) as a potential target of HgS. Unexpectedly, we discovered that HgS covalently binds to Skp1 through a "Cys62-HgS-Cys120" mode. Moreover, our findings revealed that HgS inhibits the ubiquitin-protease system through Skp1 to up-regulate SNAP-25 expression, thereby triggering synaptic vesicle exocytosis to regulate locomotion ability in
. Collectively, our findings may promote a comprehensive interpretation of the pharmacological mechanism of mercury sulfide on neuroprotective function.
An organocatalytic asymmetric synthesis of directly linked benzothiazole‐dihydroimidazoles with two adjacent tertiary‐quaternary stereocenters through a Mannich‐type reaction of isocyanoacetates with ...N‐(2‐benzothiazolyl)imines is disclosed. When employing bifunctional dihydroquinine‐derived squaramide as catalyst, moderate to excellent yields (up to 97 % yield), moderate diastereoselectivities and excellent enantioselectivities (up to >99 % ee) were obtained for a variety of substrates. In addition, the transformation of the resulted directly linked benzothiazole‐dihydroimidazole into highly functionalized α,β‐diamino esters was also demonstrated.
A practical and efficient transition‐metal‐free selective protocol has been developed for the direct synthesis of chiral directly linked benzothiazole‐dihydroimidazoles with two adjacent tertiary‐quaternary stereocenters through asymmetric Mannich‐type reaction of α‐isocyanoacetates with N‐(2‐benzothiazolyl)imines catalyzed by dihydroquinine‐derived squaramide under the mild conditions for the first time.
The physiology of gastric acid secretion is one of the earliest subjects in medical literature and has been continuously studied since 1833. Starting with the notion that neural stimulation alone ...drives acid secretion, progress in understanding the physiology and pathophysiology of this process has led to the development of therapeutic strategies for patients with acid-related diseases. For instance, understanding the physiology of parietal cells led to the developments of histamine 2 receptor blockers, proton pump inhibitors (PPIs), and recently, potassium-competitive acid blockers. Furthermore, understanding the physiology and pathophysiology of gastrin has led to the development of gastrin/CCK
receptor (CCK
R) antagonists. The need for refinement of existing drugs in patients have led to second and third generation drugs with better efficacy at blocking acid secretion. Further understanding of the mechanism of acid secretion by gene targeting in mice has enabled us to dissect the unique role for each regulator to leverage and justify the development of new targeted therapeutics for acid-related disorders. Further research on the mechanism of stimulation of gastric acid secretion and the physiological significances of gastric acidity in gut microbiome is needed in the future.
Mitochondrial fusion/fission dynamics plays a fundamental role in neuroprotection; however, there is still a severe lack of therapeutic targets for this biological process. Here, we found that the ...naturally derived small molecule echinacoside (ECH) significantly promotes mitochondrial fusion progression. ECH selectively binds to the previously uncharacterized casein kinase 2 (CK2) α' subunit (CK2α') as a direct cellular target, and genetic knockdown of CK2α' abolishes ECH-mediated mitochondrial fusion. Mechanistically, ECH allosterically regulates CK2α' conformation to recruit basic transcription factor 3 (BTF3) to form a binary protein complex. Then, the CK2α'/BTF3 complex facilitates β-catenin nuclear translocation to activate TCF/LEF transcription factors and stimulate transcription of the mitochondrial fusion gene Mfn2. Strikingly, in a mouse middle cerebral artery occlusion (MCAO) model, ECH administration was found to significantly improve cerebral injuries and behavioral deficits by enhancing Mfn2 expression in wild-type but not CK2α'
mice. Taken together, our findings reveal, for the first time, that CK2 is essential for promoting mitochondrial fusion in a Wnt/β-catenin-dependent manner and suggest that pharmacologically targeting CK2 is a promising therapeutic strategy for ischemic stroke.
AbstractDespite extensive investigations of bond stress versus slip modeling for RC structures, most existing bond stress–slip models are incomplete, discontinuous, and insufficiently accurate. These ...problems can cause nonconvergence and other difficulties in computational simulations of concrete structures that use bond-slip models. Through systematical analyses of an existing database of bond-slip behavior and data regressions, this work develops a unified bond stress–slip model that overcomes these difficulties and is suitable for numerical simulations. The model is given by a single and mathematically continuous equation that does not distinguish between plain and confined concrete or splitting and pullout failure because such judgments are arrived at automatically by evaluating the model parameters. Furthermore, the model outperforms the existing models in the precision of its predictions.
New real structure-preserving decompositions are introduced to develop fast and robust algorithms for the (right) eigenproblem of general quaternion matrices. Under the orthogonally JRS-symplectic ...transformations, the Francis JRS-QR step and the JRS-QR algorithm are firstly proposed for JRS-symmetric matrices and then applied to calculate the Schur form of quaternion matrices. A novel quaternion Givens matrix is defined and utilized to compute the QR factorization of quaternion Hessenberg matrices. An implicit double shift quaternion QR algorithm is presented with a technique for automatically choosing shifts and within real operations. Numerical experiments are provided to demonstrate the efficiency and accuracy of newly proposed algorithms.
Quantum dots (QDs) are a class of nanomaterials with good optical properties. Compared with organic dyes, QDs have unique photophysical properties: size-tunable light emission, improved signal ...brightness, resistance against photobleaching, and simultaneous excitation of multiple fluorescence colors. Possessing versatile surface chemistry and superior optical features, QDs are useful in a variety of
in vitro
and
in vivo
applications. When linked with targeting biomolecules, QDs can be used to target cell biomarkers because of high luminescence and stability. So QDs have the potential to become a novel class of fluorescent probes. This review outlines the basic properties of QDs, cell fluorescence labeling, and tumor diagnosis imaging and discusses the future directions of QD-focused bionanotechnology research in the life sciences.
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