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The rich physical properties unveiled in a plethora of transition and rare-earth metal oxides have been attributed to the intricate interplays between the orbital, charge, and spin degrees of freedom. Among them, rare-earth manganites (RMnO3) have been attracting tremendous attention owing to the ionic size-induced lattice distortion dictated by the Goldschmidt tolerance factor and the substantial Jahn–Teller distortion unique to Mn3+ ions, which evidently have resulted in a variety of emergent characteristics in electronic, magnetic, and orbital ordering. In this work, we deliberately engineered the orientation of a series of orthorhombic YMnO3 (o-YMO) films grown on SrTiO3(100) [STO(100)] and SrTiO3(110) [STO(110)] substrates by means of pulsed laser deposition. The x-ray diffraction (XRD) and reciprocal space mapping revealed that o-YMO/STO(100) is c-axis-oriented and o-YMO/STO(110) is a-axis-oriented, respectively. The XRD ϕ-scans further indicate that both films have excellent in-plane crystallinity, allowing the exploration of anisotropies along the respective crystallographic orientations. Indeed, the x-ray absorption linear dichroism spectroscopy taken along the respective crystallographic orientations evidently exhibited substantial anisotropy. Theoretical fitting with configuration interaction cluster calculations suggests that the d 3 z 2 − r 2 orbitals are parallel to YMO[001]/(100), leading to stronger electron scattering along the c-axis. Independent polarization-dependent Δ R/R spectra obtained using the femtosecond pump–probe method exhibited substantial anisotropic behaviors in carrier relaxation dynamics when probing along different crystallographic orientations, presumably due to orbital ordering anisotropies. [ABSTRACT FROM AUTHOR]

New synthetic routes were devised for total synthesis of Fe3+‐bound (ferri−) salmycin B (Sal B) (1), glycan‐based Sal analogues 2–5 and their Fe3+‐unbound (desferri−) counterparts 1′–5′ for the structure to activity relationship (SAR) study. The results of SAR study reveal the effective structure of 1 and its desferri‐counterpart 1′ that are responsible for the observed inhibitory activity against Staphylococcus aureus (S. aureus). Among the analogues 2–5 and 2′–5′, glucose‐based analogue 2 and its desferri‐counterpart 2′ exhibited inhibitory potency comparable to 1 and 1′. Chemical modification of 2′ for further antibacterial study enabled us to discover desferri‐Sal analogue 7′ that endowed with a simpler pharmacophore structure but significantly higher antibacterial potency against methicillin‐sensitive and resistant S. aureus than the natural product 1′ and even the clinical vancomycin. Together with a better hydrolytic stability and shorter synthetic route, the analogue 7′ represents an attractive antibiotic lead for further exploration. [ABSTRACT FROM AUTHOR]

This work reports molecular beam epitaxy (MBE) of two-dimensional (2D) GaSe1−xTex ternary alloys that have recently attracted a lot of interest in physics for prospective electronics and optoelectronics even though they face crucial challenges in their epitaxial technology. Disregarding a distinction in crystal phase symmetry of two end-terminals, i.e., hexagonal-GaSe (h-GaSe) and monoclinic-GaTe (m-GaTe), the majority of hexagonal-GaSe1−xTex (h-GaSe1−xTex) phase on a GaN/sapphire platform is guaranteed under our specific growth conditions without a visible sign of phase transition. We have also proposed extracting the Te composition of the ternary alloy via the experimental in-plane lattice constant, which is consistent with those indicated from energy dispersion X-ray data. Fascinatingly, the experimental and predictable band emission versus Te content displays a continuous redshift from 1.78 eV (h-GaSe) to 1.25 eV (h-GaSe0.4Te0.6) then a reversible blueshift to 1.46 eV (h-GaTe). Importantly, benefiting from the presence of Te incorporated atoms, the photoresponse performance of the hexagonal ternary alloy has greatly enhanced in comparison to the h-GaSe binary in terms of photocurrent density (up to 1250 nA cm−2 for h-GaSe0.65Te0.35 at only 300 mV bias). Overall, the results pave a way for phase/physical engineering of the alloys through the MBE process and realizing self-powered wafer-scale photodetectors based on 2D Ga-based monochalcogenide epitaxial thin films. [ABSTRACT FROM AUTHOR]

The magneto-structural coupling of BiFeO3 (BFO)–CoFe2O4 (CFO)/LaAlO3 (LAO) heteroepitaxy with various lateral sizes of CFO pillars embedded in a BFO matrix was investigated. A structural phase transformation of the BFO matrix was observed when the pillar size of CFO was increased to exceed 200 nm. Such structural transformation led to modification of magneto-elastic coupling behavior and magnetic anisotropy in the BFO–CFO/LAO system. The flexibility of tuning the pillar size of CFO, and hence, the strain and interfacial effect on the multiferroic system have significant application implications in these functional oxide nanocomposites. [ABSTRACT FROM AUTHOR]

Interest in bringing p- and n-type monolayer semiconducting transition metal dichalcogenides (TMD) into contact to form rectifying pn diode has thrived since it is crucial to control the electrical properties in two-dimensional (2D) electronic and optoelectronic devices. Usually this involves vertically stacking different TMDs with pn heterojunction or, laterally manipulating carrier density by gate biasing. Here, by utilizing a locally reversed ferroelectric polarization, we laterally manipulate the carrier density and created a WSe2 pn homojunction on the supporting ferroelectric BiFeO3 substrate. This non-volatile WSe2 pn homojunction is demonstrated with optical and scanning probe methods and scanning photoelectron micro-spectroscopy. A homo-interface is a direct manifestation of our WSe2 pn diode, which can be quantitatively understood as a clear rectifying behavior. The non-volatile confinement of carriers and associated gate-free pn homojunction can be an addition to the 2D electron-photon toolbox and pave the way to develop laterally 2D electronics and photonics. Bringing together p- and n-type monolayers of semiconducting transition metal dichalcogenides results in the formation of atomically thin pn junctions. Here, the authors laterally manipulate carrier density to create a WSe2 pn homojunction on a supporting ferroelectric BiFeO3 substrate. [ABSTRACT FROM AUTHOR]

As a common medicinal and edible resource in China, Coicis Semen has a long history of cultivation and medicinal use. Traditional Chinese medicine(TCM) clinically believes that Coicis Semen has the effect of strengthening the spleen and tonifying the lungs, clearing heat and dampness, removing pus and paralysis, and stopping diarrhea. Therefore, it is used to treat edema, foot odor, spleen deficiency, diarrhea, and other symptoms. The above effects are closely related to the active ingredients of Coicis Semen, such as esters, fatty acids, polysaccharides, proteins, as well as phenolic acids, sterols, flavonoids, lactams, triterpenes, alkaloids, and adenosine. Modern research has found that Coicis Semen also has anti-cancer, anti-inflammatory, antioxidant, hypoglycemic, and hypotensive effects and other pharmacological activities, and it can improve immunity and regulate lipid metabolism. Coicis Semen is widely distributed in China, mainly produced in Guizhou, Yunnan, Fujian, Sichuan, and other places, and the quality of Coicis Semen from different origins varies. From ancient times to the present, Coicis Semen processing methods have experienced the process from simple to complex, and the types of auxiliary materials are more extensive, such as soil, bran, and river sand. These processing methods have been inherited from generation to generation. Nowadays, the commonly used methods are bran-fried, stir-fried, sand-fried, etc. In this paper, by reviewing the relevant literature in China and abroad in recent years, the main active ingredients and related pharmacological effects of Coicis Semen are sorted out, and the effects of different origins and processing methods on the chemical composition of Coicis Semen are summarized, with a view to providing references for the comprehensive development and utilization of Coicis Semen and the further study of its mechanism of action.

To elucidate the mechanism of Euodiae Fructus stir-fried with water decoction of Coptidis Rhizoma in the treatment of chronic colitis, this study employed ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS), network pharmacology, and experimental verification to predict the involved targets and signaling pathways. The chronic colitis mouse model was constructed to verify the core targets. A total of 48 compounds in the herbal medicine were identified by UPLC-Q-TOF-MS. SwissTargetPrediction was used to screen the potential active components and drug targets. GeneCards, OMIM, PharmGKB, and TDD were used to search for the disease targets. A total of 31 active ingredients, 453 targets of the herbal medicine, and 3 960 targets of chronic colitis were obtained. The common targets shared by the herbal medicine and chronic colitis were introduced into STRING to construct the protein-protein interaction(PPI) network, and CytoNCA plug-in was used to screen the key targets. A total of 90 key targets were obtained, and the key active components included isorhamnetin, quercetin, limonin, and oxyberberine. GO annotation and KEGG pathway enrichment for the key targets were carried out via DAVID. The targets were mainly involved in the positive regulation of protein phosphorylation, positive regulation of nitric oxide biosynthetic process, and negative regulation of apoptotic process. The medicine may treat chronic colitis through PI3 K-Akt, VEGF, HIF-1, and TNF signaling pathways. A mouse model of chronic colitis was established and then treated with Euodiae Fructus stir-fried with the water decoction of Coptidis Rhizoma. The experimental results demonstrated that the medicine can alleviate the pathological damage of colon, significantly reduce the levels of IL-1β, IL-6, and TNF-α, inhibit the activation of PI3 K/Akt pathway, and down-regulate the expression of VEGFA in the treatment of chronic colitis.

Interest in bringing p- and n-type monolayer semiconducting transition metal dichalcogenides (TMD) into contact to form rectifying pn diode has thrived since it is crucial to control the electrical properties in two-dimensional (2D) electronic and optoelectronic devices. Usually this involves vertically stacking different TMDs with pn heterojunction or, laterally manipulating carrier density by gate biasing. Here, by utilizing a locally reversed ferroelectric polarization, we laterally manipulate the carrier density and created a WSe 2 pn homojunction on the supporting ferroelectric BiFeO 3 substrate. This non-volatile WSe 2 pn homojunction is demonstrated with optical and scanning probe methods and scanning photoelectron micro-spectroscopy. A homo-interface is a direct manifestation of our WSe 2 pn diode, which can be quantitatively understood as a clear rectifying behavior. The non-volatile confinement of carriers and associated gate-free pn homojunction can be an addition to the 2D electron-photon toolbox and pave the way to develop laterally 2D electronics and photonics.