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GaAs-based quaternary ferromagnetic semiconductor (Ga, Mn)(As, Sb) has been successfully prepared by molecular-beam epitaxy. High-resolution x-ray diffraction measurements indicate that the lattice constant has a notable alteration with changing Sb content. Magnetic measurements demonstrate the same evolution of the Curie temperature TC and the effective Mn content xeff with increasing Sb content. The incorporation of low Sb content is of benefit to increasing xeff, thus, increasing TC. However, higher Sb content degrades the crystal quality, resulting in a decrease of xeff. Experimental results show that TC is proportional to the product of xeff and p1/3, which is consistent with the Zener Model. The exchange energy N0β is calculated to be -1.09 eV, which is similar to that of (Ga, Mn)As. [ABSTRACT FROM AUTHOR]

A new cepstral analysis procedure with the complex cepstrum for recovering excitations causing multiple transient signal components from vibration signals, especially from rotor vibration signals, has been developed. Along with the problem of singularity, a major problem of the cepstrum is that it cannot provide a correct distribution of the excitations. To solve these problems, a signal preprocessing method, whose function is to provide a definition for the distribution of the excitations along the quefrency axis and remove singular points from the transform, has been added to the cepstrum analysis. With this procedure, a correct distribution of the excitations can be obtained. An example of application to the condition monitoring of rotor machinery is also presented. [DOI: 10.1115/1.1356696]

RNAs and their encoded proteins intricately regulate diverse cell types and states within the human body. Dysregulated RNA expressions or mutations can lead to various diseased cell states, including tumorigenesis. Detecting and manipulating these endogenous RNAs offers significant promise for restoring healthy cell states and targeting tumors both in research and clinical contexts. This study presents an RNA-IN and RNA-OUT genetic circuit capable dynamically sensing and manipulating any RNA target in a programmable manner. The RNA-IN module employes a programmable CRISPR-associated protease (CASP) complex for RNA detection, while the RNA-OUT module utilizes an engineered protease-responsive dCas9-VPR activator. Additionally, the CASP module can detect point mutations by harnessing an uncovered dual-nucleotide synergistic switching effect within the CASP complex, resulting in the amplification of point-mutation signals from initially undetectable levels (1.5-fold) to a remarkable 94-fold. We successfully showcase the circuit's ability to rewire endogenous RNA-IN signals to activate endogenous progesterone biosynthesis pathway, dynamically monitor adipogenic differentiation of mesenchymal stem cells (MSCs) and the epithelial-to-mesenchmal trans-differentiation, as well as selective killing of tumor cells. The programmable RNA-IN and RNA-OUT circuit exhibits tremendous potential for applications in gene therapy, biosensing and design of synthetic regulatory networks., (© 2024. The Author(s).)

Nature has created various organisms with unique chemical components and multi-scale structures (e.g., foot proteins, toe pads, suckers, setose gill lamellae) to achieve wet adhesion functions to adapt to their complex living environments. These organisms can provide inspirations for designing wet adhesives with mediated drug release behaviors in target locations of biological surfaces. They exhibit conformal and enhanced wet adhesion, addressing the bottleneck of weaker tissue interface adhesion in the presence of body fluids. Herein, it is focused on the research progress of different wet adhesion and bioinspired fabrications, including adhesive protein-based adhesion and inspired adhesives (e.g., mussel adhesion); capillarity and Stefan adhesion and inspired adhesive surfaces (e.g., tree frog adhesion); suction-based adhesion and inspired suckers (e.g., octopus' adhesion); interlocking and friction-based adhesion and potential inspirations (e.g., mayfly larva and teleost adhesion). Other secreted protein-induced wet adhesion is also reviewed and various suckers for other organisms and their inspirations. Notably, one representative application scenario of these bioinspired wet adhesives is highlighted, where they function as efficient drug delivery platforms on target tissues and/or organs with requirements of both controllable wet adhesion and optimized drug release. Finally, the challenges of these bioinspired wet drug delivery platforms in the future is presented., (© 2024 Wiley‐VCH GmbH.)

Patients with tissue inflammation or injury often experience aberrant mechanical pain hypersensitivity, one of leading symptoms in clinic. Despite this, the molecular mechanisms underlying mechanical distortion are poorly understood. Canonical transient receptor potential (TRPC) channels confer sensitivity to mechanical stimulation. TRPC3 and TRPC6 proteins, coassembling as heterotetrameric channels, are highly expressed in sensory neurons. However, how these channels mediate mechanical pain hypersensitivity has remained elusive. It is shown that in mice and human, TRPC3 and TRPC6 are upregulated in DRG and spinal dorsal horn under pathological states. Double knockout of TRPC3/6 blunts mechanical pain hypersensitivity, largely by decreasing nociceptor hyperexcitability and spinal synaptic potentiation via presynaptic mechanism. In corroboration with this, nociceptor-specific ablation of TRPC3/6 produces comparable pain relief. Mechanistic analysis reveals that upon peripheral inflammation, TRPC3/6 in primary sensory neurons get recruited via released bradykinin acting on B1/B2 receptors, facilitating BDNF secretion from spinal nociceptor terminals, which in turn potentiates synaptic transmission through TRPC3/6 and eventually results in mechanical pain hypersensitivity. Antagonizing TRPC3/6 in DRG relieves mechanical pain hypersensitivity in mice and nociceptor hyperexcitability in human. Thus, TRPC3/6 in nociceptors is crucially involved in pain plasticity and constitutes a promising therapeutic target against mechanical pain hypersensitivity with minor side effects., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Mechanically interlocked molecules (MIMs) are promising platforms for developing functionalized artificial molecular machines. The construction of chiral MIMs with appealing circularly polarized luminescence (CPL) properties has boosted their potential application in biomedicine and the optical industry. However, there is currently little knowledge about the CPL emission mechanism or the emission dynamics of these related MIMs. Herein, we demonstrate that time-resolved circularly polarized luminescence (TRCPL) spectroscopy combined with transient absorption (TA) spectroscopy offers a feasible approach to elucidate the origins of CPL emission in pyrene-functionalized topologically chiral [2]catenane as well as in a series of pyrene-functionalized chiral molecules. For the first time, direct evidence differentiating the chiroptical signals originating from either topological (local state emission) or Euclidean chirality (excimer state emission) in these pyrene-functionalized chiral molecules has been discovered. Our work not only establishes a novel and ideal approach to study CPL mechanism, but also provides a theoretical foundation for the rational design of novel chiral materials in the future., (© 2024 Wiley-VCH GmbH.)

Malaria infections affect almost half of the world's population, with over 200 million cases reported annually. Cryptolepis sanguinolenta, a plant native to West Africa, has long been used across various regions of Africa for malaria treatment. Chemical analysis has revealed that the plant is abundant in indoloquinolines, which have been shown to possess antimalarial properties. Cryptolepine, neocryptolepine, and isocryptolepine are well-studied indoloquinoline alkaloids known for their potent antimalarial activity. However, their structural rigidity and associated cellular toxicity are major drawbacks for preclinical development. This review focuses on the potential of indoloquinoline alkaloids (cryptolepine, neocryptolepine, and isocryptolepine) as scaffolds in drug discovery. The article delves into their antimalarial effects in vitro and in vivo, as well as their proposed mechanisms of action and structure-activity relationship studies. Several studies aim to improve these leads by reducing cytotoxicity while preserving or enhancing antimalarial activity and gaining insights into their mechanisms of action. These investigations highlight the potential of indoloquinolines as a scaffold for developing new antimalarial drugs., (© 2024 The Authors. ChemMedChem published by Wiley-VCH GmbH.)

To explore the chirality induction and switching of topological chirality, poly[2]catenanes composed of helical poly(phenylacetylenes) (PPAs) main chain and topologically chiral [2]catenane pendants are described for the first time. These poly[2]catenanes with optically active [2]catenanes on side chains were synthesized by polymerization of enantiomerically pure topologically chiral [2]catenanes with ethynyl polymerization site and/or point chiral moiety. The chirality information of [2]catenane pendants was successfully transferred to the main chain of polyene backbones, leading to preferred-handed helical conformations, while the introduction of point chiral units has negligible effect on the overall helices. More interestingly, attributed to unique dynamic feature of the [2]catenane pendants, these polymers revealed dynamic response behaviors to solvents, temperature, and sodium ions, resulting in the fully reversible switching on/off of the chirality induction. This work provides not only new design strategy for novel chiroptical switches with topologically chiral molecules but also novel platforms for the development of smart chiral materials., (© 2024 Wiley-VCH GmbH.)

Molecules bearing carboxylic acid, amide, and hydroxyl groups are ubiquitous in crystal engineering, where robust hydrogen-bonded synthons centred on these functionalities enable reliable crystal structure design. We now show that halogen bonding to the carbon π-system of such molecules, traditionally ignored in crystal engineering, permits the recognition and directional assembly of the resulting hydrogen-bonded structural subunits, leaving the archetypal hydrogen-bonded ring, ladder, and chain homosynthons intact, but repositioned in space. When applied to heteromolecular synthons, this enables rearranging more complex hydrogen-bonded motifs and the evolution of binary cocrystals into ternary ones through "latent" carbon-based recognition sites, demonstrating a rational approach to build higher-order solid-state supramolecular assemblies., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Lithium-sulfur (Li-S) batteries are considered as a most promising rechargeable lithium metal batteries because of their high energy density and low cost. However, the Li-S batteries mainly suffer the capacity decay issue caused by the shutting effect of lithium polysulfides and the safety issues arising from the Li dendrites formation. This review outlines the current issues of Li-S batteries. Furthermore, we comprehensively summarized the challenges encountered by Li anode in Li-S batteries, such as the heterogeneous deposition of the Li anode, the unstable solid electrolyte interface (SEI) layer, and volume expansion. Moreover, research progresses in the stabilization strategies of Li anodes (physical approaches, optimization of electrolyte, surface protection layer, and design of current collector) is discussed in detail. Lastly, the remaining challenges and future research directions of Li metal anode stabilization in Li-S batteries are also present., (© 2024 Wiley-VCH GmbH.)

Centrosomes are the canonical microtubule organizing centers (MTOCs) of most mammalian cells, including spermatocytes. Centrosomes comprise a centriole pair within a structurally ordered and dynamic pericentriolar matrix (PCM). Unlike in mitosis, where centrioles duplicate once per cycle, centrioles undergo two rounds of duplication during spermatogenesis. The first duplication is during early meiotic prophase I, and the second is during interkinesis. Using mouse mutants and chemical inhibition, we have blocked centriole duplication during spermatogenesis and determined that non-centrosomal MTOCs (ncMTOCs) can mediate chromosome segregation. This mechanism is different from the acentriolar MTOCs that form bipolar spindles in oocytes, which require PCM components, including gamma-tubulin and CEP192. From an in-depth analysis, we identified six microtubule-associated proteins, TPX2, KIF11, NuMA, and CAMSAP1-3, that localized to the non-centrosomal MTOC. These factors contribute to a mechanism that ensures bipolar MTOC formation and chromosome segregation during spermatogenesis when centriole duplication fails. However, despite the successful completion of meiosis and round spermatid formation, centriole inheritance and PLK4 function are required for normal spermiogenesis and flagella assembly, which are critical to ensure fertility., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep wells. This paper aims to predict the casing burst strength with considerations of both wear and corrosion. Firstly, the crescent wear shape is simplified into three categories according to common mathematical models. Then, based on the mechano-electrochemical (M-E) interaction, the prediction model of corrosion depth is built with worn depth as the initial condition, and the prediction models of burst strength of the worn casing and corroded casing are obtained. Secondly, the accuracy of different prediction models is validated by numerical simulation, and the main influence factors on casing strength are obtained. At last, the theoretical models are applied to an ultra-deep well in Northwest China, and the dangerous well sections caused by wear and corrosion are predicted, and the corrosion rate threshold to ensure the safety of casing is obtained. The results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth growth. The accuracy of different mathematical models is different: the slot ring model is most accurate for predicting corrosion depth, and the eccentric model is most accurate for predicting the burst strength of corroded casing. The burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected, so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the wear resistance and fatigue spalling damage of wheel and rail materials with and without laser cladding coating under oil lubrication using a rolling–sliding machine. It illustrates that the laser cladding Co-based alloy coating improves the wear resistance of wheel and rail rollers. Serious spalling is dominant for untreated wheel and rail rollers. The wheel or rail roller undergoing laser cladding treatment takes on slight abrasive wear and visible ploughing. Furthermore, there are no cracks on the contact surface and subsurface. The laser cladding Co-based alloy coating exhibits outstanding resistance to wear and fatigue spalling damage due to its microstructure in the coating under oil lubrication. [ABSTRACT FROM PUBLISHER]

A numerical model of wheel and rail lubricated by a third body was established using the partial elasto-hydrodynamic lubrication theory and multi-grid method. The effects of rolling speed, surface roughness, contact load, wheel diameter, and viscosity of third body on adhesion coefficient are explored. The results show that the rolling speed, surface roughness, and the viscosity of third body have a significant influence on adhesion coefficient when the wheel/rail interface is lubricated under oil and water conditions. Furthermore, to verify the precision of the numerical calculating results, some experiments were carried out by means of a JD-1 wheel/rail simulation facility. The results show that there is same changing trend and almost same adhesion coefficient between the curves of numerical and experimental results. The relative difference between the numerical and experimental results is less than 10%. This numerical method can be used to explore the adhesion coefficient of wheel/rail under the third body condition. [ABSTRACT FROM AUTHOR]

In this paper, steel fibre is applied to reinforce pre-stressed high-strength concrete pile in order to improve its seismic performance. The pre-stressed high-strength concrete piles reinforced with shearing J-end steel fibre and steel-wire J-end steel fibre, respectively, are selected here for low-reversed cyclic loading test to analyse the ductility, rigidity degeneration and energy dissipating capacity of such components. The results show that the ductility of pre-stressed high-strength concrete pile reinforced with steel fibre is not improved significantly while the horizontal bearing capacity is enhanced. [ABSTRACT FROM AUTHOR]

Reducing the resistivity of low temperature grown p-Al0.09Ga0.91N layers is crucial to improving the performance of GaN-based laser diodes. In this study, growth conditions of low temperature grown p-Al0.09Ga0.91N layers are monitored and the role of C impurity is investigated systematically. On the basis of the dependence of resistivity on C concentration and the photoluminescence analysis, it is found that C impurities act as donors in p-Al0.09Ga0.91N layer, and reducing the C concentration can reduce its compensation effect on Mg acceptor. Finally, a low resistivity of 4.2 Ω·cm is achieved for the low temperature grown p-Al0.09Ga0.91N. [ABSTRACT FROM AUTHOR]

OBJECTIVE: MiR-155 has been shown to be up-regulated in hepatocellular carcinoma (HCC) patients. B-cell lymphoma-2 (Bcl-2) interacting mediator of cell death (BIM) regulates cell proliferation and apoptosis, as its down-regulation is involved in HCC onset. Transcriptional factor FoxO3a mediates BIM expression and is related to HCC pathogenesis. Bioinformatics analysis showed targeted regulation of FoxO3a by miR-155. This study aims to investigate whether miR-155 plays a role in mediating FoxO3a/BIM signal pathway and HCC occurrence. PATIENTS AND METHODS: HCC patients were collected for tumor and adjacent tissues, in which microRNA-155 (miR-155) and FoxO3a expressions were examined. In vitro cultured HCCLM3, HepG2 and L-02 cells were tested for basal apoptotic rate by flow cytometry and were compared for miR-155 and FoxO3a expression. Dual-luciferase reporter gene assay demonstrated the targeted relationship between miR-155 and FoxO3a. HCCLM3 cells were treated with miR-155 inhibitor and/or FoxO3a-pMD18-T. Cell apoptosis and proliferation were examined by using flow cytometry and MTT assays, respectively. Western blot and spectrometry assay were employed to quantify the FoxO3a, BIM expressions, and caspase activity. RESULTS: Compared to adjacent tissues, HCC tissues had significantly higher miR-155 and significantly lower FoxO3a expression (p<0.05). HCCLM3 and HepG2 cells had significantly lower FoxO3a expression and basal apoptotic rate compared to L02 cells, whilst miR-155 level was significantly higher (p<0.05). MiR-155 targeted and inhibited 3'-UTR of FoxO3a, increasing BIM expression, caspase-3, and caspase-9 activities, and enhancing cell apoptosis and weakening proliferation. CONCLUSIONS: HCC tissues elevated the miR-155 and suppressed the FoxO3a expressions. MiR-155 targeted and inhibited FoxO3a expression to suppress the BIM, depress caspase-3 and caspase-9 activities, therefore inhibiting the HCC cell apoptosis and facilitating proliferation. [ABSTRACT FROM AUTHOR]

Effect of 35BaO-35ZnO-30BO (BZB) addition on the sintering behaviors, phase evolution and microwave dielectric properties of Ti-modified BaTiNbO (BaTiNbO, BTNO) ceramics had been investigated. BZB addition effectively reduced the sintering temperature of BTNO from 1250 °C to about 900 °C. With increasing BZB addition, the crystal phase of the present ceramics changed from single phase BaTiNbO to mixing phases of BaTiNbO and BaTiNbO. And the major phase gradually became from BaTiNbO to BaTiNbO. Dielectric constant and temperature coefficient increased with the rising of BZB addition. But the Qf value gradually declined from 28000 to about 6000 GHz. The BTNO ceramics with 15% BZB addition exhibited excellent microwave dielectric properties as following: ε = 46.3, Qf = 5887 GHz and τ = 35.5 ppm/°C, which was potential of candidate materials for LTCC application. And the variation of microwave dielectric properties had been also discussed with the phase and microstructure evolution. [ABSTRACT FROM AUTHOR]

The Debye temperature of wurtzite aluminum nitride (AlN) was determined by the Rietveld refinement method based on the room-temperature X-ray powder diffraction data. The refined lattice parameters are a = 3.11139(1) Å, c = 4.978 43(3) Å; the refined positional parameter for N is z = 0.384 59(33) Å; and the refined temperature factors of Al and N were 0.442(12) Å2 and 0.559(33) Å2, respectively. Using this refined temperature factor, the Debye temperature was evaluated as 971 K through the Debye approximation. [ABSTRACT FROM AUTHOR]

We consider the full compressible Navier-Stokes equations with reaction diffusion. A global existence and uniqueness result of the strong solution is established for the Cauchy problem when the initial data is in a neighborhood of a trivially stationary solution. The appearance of the difference between energy gained and energy lost due to the reaction is a new feature for the flow and brings new difficulties. To handle these, we construct a new linearized system in terms of a combination of the solutions. Moreover, some optimal time-decay estimates of the solutions are derived when the initial perturbation is additionally bounded in L1. It is worth noticing that there is no decay loss for the highest-order spatial derivatives of the solution so that the long time behavior for the hyperbolic-parabolic system is exactly the same as that for the heat equation. As a byproduct, the above time-decay estimate at the highest order is also valid for compressible Navier-Stokes equations. The proof is accomplished by virtue of Fourier theory and a new observation for cancellation of a low-medium-frequency quantity. [ABSTRACT FROM AUTHOR]