Search

Monitoring levels of excessive aluminum ions (Al3+) is crucial as it can harm the immune system, reduce enzyme activity, cause cell death, and damage environmental and biological systems. Developing a fast and efficient Al3+ion determination method is the key to addressing this issue. In this work, red-emitting fluorescent copper nanoclusters (CuNCs) were synthesized using N-acetyl-l-cysteine (NAC) as a ligand and CuCl2·2H2O through a facile procedure. The NAC-CuNCs exhibited a large Stokes shift and displayed remarkable luminescence properties. A method for detecting Al3+through a fluorescence probe was proposed. Its fluorescence mechanism was also explored. The probe showed rapid responsiveness (within 1 min) to Al3+ion determination. The detection limit for Al3+was found to be 19.7 nM, which is significantly lower than the WHO’s value and most reports, with a linear range of 0–52.9 μM. The determination of Al3+concentrations in actual water using the fluorescence probe yielded satisfactory outcomes. Moreover, the visual detection of Al3+ions was also achieved through a smartphone, which can enhance its fast and practical detection.

Al–Fe alloy is a kind of high thermal conductivity alloy, which are widely utilized in the communication and automobile industries. The thermal conductivity is greatly affected by the morphology, size, and distribution of iron-rich intermetallic phases (Fe-rich phases), pores, and Al grains. The evolution of microstructure and thermal conductivity of Al–Fe alloys by adding Sc2O3particles and adjusting cooling rates are systematically studied by optical and scanning electron microscopy, and synchrotron X-ray imaging. The results show that Sc2O3addition reduces the size and increases the number of primary Fe-rich phases, while increasing the grain size of Al matrix. The Sc2O3promote their nucleation of primary Fe-rich phases and partial Sc solutes inhibit their growth, resulting in the improvement of thermal conductivity and mechanical properties. The remaining Sc2O3particles have large lattice misfit with Al, led to the formation of coarsen size Al. The highest thermal conductivity is 214 W/(m·K) in the alloy with Sc2O3and slow cooling rate. Sc2O3addition increase the thermal conductivity of the studied alloys, i.e., an increment of 3 W/(m K) (by 1.1 %) at slow cooling rate by and an increment of 11 W/(m K) (by 6.2 %) at fast cooling rate. This study provides a new strategy to improving thermal conductivity of Al alloy for both academia and industry.

An improved white shark optimizer (MWSO) algorithm has been proposed. The algorithm adopts an improved tent chaotic mapping strategy to enhance the diversity of the initial population of white sharks, introduces the balance pool strategy of the EO algorithm to improve the convergence speed and accuracy of the algorithm, applies adaptive t-distribution dynamic selection probability perturbation to the global optimal solution, and adjusts the exploration and development ability of the algorithm at different iteration periods. MWSO, WSO, and seven excellent metaheuristic algorithms are tested and compared on 23 classic test functions and the CEC2017 test suite, and two non-parametric tests, a Wilcoxon rank sum test with a significance level of 0.05 and Friedman test, are conducted. The statistical results indicate that the proposed MWSO is significantly superior to other algorithms. In addition, nine algorithms are applied for the first time to optimize the structural parameters of the oil sealing edge of oil pads in response to the issue of the bearing capacity of hydrostatic bearings. This not only further verified the superiority of MWSO, but also provided new ideas for the optimization of hydrostatic bearings.

As a host for exchange bias (EB), van der Waals (vdW) magnetic materials have exhibited intriguing and distinct functionalities from conventional magnetic materials. The EB in most vdW systems is far below room temperature, which poses a challenge for practical applications. Here, by using Kerr microscopy, we demonstrate a record-high blocking temperature that approaches room temperature and a huge positive EB field that nears 2 kOe at 100 K in naturally oxidized two-dimensional (2D) vdW ferromagnetic Fe3GaTe2nanoflakes. Moreover, we realized a reversible manipulation of both the presence/absence and positive/negative signs of EB via a training magnetic field without multiple field cooling processes. Thus, our study clearly reveals the robust, sizable, and sign-tunable EB in vdW magnetic materials up to near room temperature, thereby establishing Fe3GaTe2as an emerging room-temperature-operating vdW material and paving the way for designing practical 2D spintronic devices.

Electrochemical water splitting, as an effective sustainable and eco-friendly energy conversion strategy, can produce high-purity hydrogen (H 2) and oxygen (O 2) via hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, altering the nonrenewable fossil fuels. Here, La 0.6 Sr 0.4 CoO 3 perovskite oxide nanoparticles with an orthorhombic phase were synthesized within 2 min in a one-step reaction, using a rapid and efficient high-temperature shock (HTS) method. Impressively, the as-prepared La 0.6 Sr 0.4 CoO 3 with orthorhombic phase (HTS-2) exhibited better OER and HER performance than the hexagonal phase counterpart prepared using the traditional muffle furnace calcination method. The electrocatalytic performance enhancement of orthorhombic La 0.6 Sr 0.4 CoO 3 can be attributed to the novel orthorhombic structure, such as confined strontium segregation, a higher percentage of highly oxidative oxygen species, and more active sites on the surface. This facile and rapid synthesis technique shows great potential for the rational design and crystal phase engineering of nanocatalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Increasing attention has been paid to the development of effective strategies for articular cartilage (AC) and osteochondral (OC) regeneration due to their limited self-reparative capacities and the shortage of timely and appropriate clinical treatments. Traditional cell-dependent tissue engineering faces various challenges such as restricted cell sources, phenotypic alterations, and immune rejection. In contrast, endogenous tissue engineering represents a promising alternative, leveraging acellular biomaterials to guide endogenous cells to the injury site and stimulate their intrinsic regenerative potential. This review provides a comprehensive overview of recent advancements in endogenous tissue engineering strategies for AC and OC regeneration, with a focus on the tissue engineering triad comprising endogenous stem/progenitor cells (ESPCs), scaffolds, and biomolecules. Multiple types of ESPCs present within the AC and OC microenvironment, including bone marrow-derived mesenchymal stem cells (BMSCs), adipose-derived mesenchymal stem cells (AD-MSCs), synovial membrane-derived mesenchymal stem cells (SM-MSCs), and AC-derived stem/progenitor cells (CSPCs), exhibit the ability to migrate toward injury sites and demonstrate pro-regenerative properties. The fabrication and characteristics of scaffolds in various formats including hydrogels, porous sponges, electrospun fibers, particles, films, multilayer scaffolds, bioceramics, and bioglass, highlighting their suitability for AC and OC repair, are systemically summarized. Furthermore, the review emphasizes the pivotal role of biomolecules in facilitating ESPCs migration, adhesion, chondrogenesis, osteogenesis, as well as regulating inflammation, aging, and hypertrophy-critical processes for endogenous AC and OC regeneration. Insights into the applications of endogenous tissue engineering strategies for in vivo AC and OC regeneration are provided along with a discussion on future perspectives to enhance regenerative outcomes.

This study explores the innovative application of piperazine as a water-soluble cross-linking and solubilizing agent in the synthesis of polyimide (PI) aerogels through freeze-drying. Piperazine was used to dissolve poly(amic acid) (PAA) into salt and cross-link it into a 3D network structure. A suite of analytical techniques characterized the interaction between piperazine and PAA, including Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (NMR). These methods elucidated the mechanisms of salt formation and chemical cross-linking. The performance and microstructure of PI aerogels with different structures were also evaluated by compression strength, cyclic compression, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The results demonstrate that piperazine significantly enhances PI aerogels’ compressive strength, resilience, and thermal insulation properties. This study provides a cost-effective and environmentally friendly approach to producing high-performance PI aerogels using freeze-drying and provides fresh insight into PI aerogel preparation.

Substituting hydrogen with deuterium in drug molecules is an appealing bioisosteric strategy for the generation of novel chemical entities in drug development. Optimizing lead compounds through deuteration has proven to be challenging and unpredictable, particularly for compounds with multiple metabolic sites. This study presents the pioneering achievement of substituting up to 19 hydrogen atoms with deuterium on 1,4-benzodiazepine-2,5-dione derivatives, shedding light on the structure–metabolism relationship and the impact of multiple deuterations on drug-like properties. Notably, the deuterated compound 3fexhibited remarkable antitumor activity in vivoand demonstrated favorable drug-like properties as a drug candidate.

AbstractThe mandibular glands (MGs) of honey bee workers are key exocrine glands responsible for the biosynthesis of multiple royal jelly acids, which have important functions within the colony. However, our knowledge about the nutrition requirement of MGs is quite limited. Here, we artificially manipulated the nutritional status of caged honey bee workers (pollen and sugar candy, sugar candy only, soybean meal and sugar candy, stearic acid supplemented sugar candy or citric acid supplemented sugar candy). Then we measured their impact on the 10-hydroxy-2-decanoic acid (10-HDA) and 10-hydroxydecanoic acid (10-HDAA) content in honey bee heads to evaluate the synthesis ability of workers’ MGs, and analyzed the protein content of MGs as well as gene expression in the MGs to reveal the possible physiological changes. Our result showed that nutrition strongly impacted the MGs acid synthesis, the 10-HDA and 10-HDAA contents were significantly higher in workers fed with pollen than with sugar candy only, while an additional supply of protein and organic acid showed no significant contribution. In addition, the 10-HDA/10-HDAA ratio was also significantly affected by the nutrition status. On the contrary, different diets showed no influence on the protein content or gene expressions of MGs, except that organic acid supplements could increase the expression of key genes in fatty acid β-oxidation pathways. Taken together, our study revealed that honey bee nutritional status is closely related to the function of worker MGs. The nutritional deficiency has a significant negative impact on the synthesis ability of worker MGs, but showed no effect on the physiology of MGs.

Exogenous polysulfhydryls (R-SH) supplementation and nitric oxide (NO) gas molecules delivery provide essential antioxidant buffering pool components and anti-inflammatory species in cellular defense against injury, respectively. Herein, the intermolecular disulfide bonds in bovine serum albumin (BSA) molecules were reductively cleaved under native and mild conditions to expose multiple sulfhydryl groups (BSA-SH), then sulfhydryl-nitrosylated (R-SNO), and nanoprecipitated to form injectable self-sulfhydrated, nitro-fixed albumin nanoparticles (BSA-SNO NPs), allowing albumin to act as a NO donor reservoir and multiple sulfhydryl group transporter while also preventing unfavorable oxidation and self-cross-linking of polysulfhydryl groups. In two mouse models of ischemia/reperfusion-induced and endotoxin-induced acute liver injury (ALI), a single low dosage of BSA-SNO NPs (S-nitrosothiols: 4 μmol·kg–1) effectively attenuated oxidative stress and systemic inflammation cascades in the upstream pathophysiology of disease progression, thus rescuing dying hepatocytes, regulating host defense, repairing microcirculation, and restoring liver function. By mechanistically upregulating the antioxidative signaling pathway (Nrf-2/HO-1/NOQ1) and inhibiting the inflammatory cytokine storm (NF-κB/p-IκBα/TNF-α/IL-β), BSA-SNO NPs blocked the initiation of the mitochondrial apoptotic signaling pathway (Cyto C/Bcl-2 family/caspase-3) and downregulated the cell pyroptosis pathway (NLRP3/ASC/IL-1β), resulting in an increased survival rate from 26.7 to 73.3%. This self-sulfhydrated, nitro-fixed functionalized BSA nanoformulation proposes a potential drug-free treatment strategy for ALI.

Accurately estimating the flow rate of gas–liquid two-phase flow is crucial for reducing costs, improving efficiency, and optimizing management in multiphase industries. However, due to the inherent complexity of multiphase flow, this task remains highly challenging. In this article, we propose a flow rate estimation method for gas–liquid two-phase flow based on Transformer neural network (TNN). The proposed method utilizes Transformer encoder layers to extract flow rate features and effectively fuses these features at various levels through the stacking of layer outputs. Compared with previous methods based on recurrent neural network (RNN), this method can process data more effectively in parallel by extracting flow rate features through the self-attention mechanism. The experimental results show that the proposed method achieves more accurate flow rate estimation across various performance indicators, compared with other deep learning-based models. In the robustness experiments against noise, the proposed method shows good robustness, demonstrating its significant potential in accurately estimating flow rates in gas–liquid two-phase flow scenarios.

In this work, we propose an efficient method for the direction of arrival (DOA) estimation of strictly noncircular incoherently distributed (ID) sources, taking into account gain-phase uncertainties and assuming that a portion of the array is well-calibrated. The proposed method uses the first-order Taylor expansion to construct an augmented generalized array manifold (GAM) that exploits the noncircularity property of the signals. Subsequently, the DOAs and gain-phase uncertainties are estimated by exploiting the array shift-invariance. Additionally, the angular spreads are estimated based on the central moments of their angular distributions. To gauge the performance of the discussed estimators, we establish a benchmark by deriving the Cramér-Rao bound (CRB) for the concerned DOA estimation problem. Generally, the proposed method presents a comprehensive and efficient solution for parameter estimation of strictly noncircular ID sources, addressing gain-phase uncertainties and accommodating various angular distributions. The simulations serve to validate the superiority of the proposed method.

The integration of phase change materials (PCMs) with planar multilayer structures, metasurfaces, waveguides, and photonic integrated circuits has triggered a technological revolution in nonvolatile tunable nanophotonic devices. The performance of devices is largely determined by PCMs, which is highly desired to have a high optical contrast and switchable capability. Here, we present a novel material platform based on Ge0.9 Sb0.1 Te suitable for nanophotonics applications across the entire visible spectral region. Ge0.9 Sb0.1 Te exhibits an optical contrast of up to 66%, significantly higher than that of the most widely reported Ge2Sb2Te5 (30%~35%) and GeTe (45%~50%). Through experiments and first-principles calculations, we reveal that this excellent performance originates from the unique solid-solution structure of crystalline Ge0.9 Sb0.1 Te, which combines high structural order with a narrow optical band gap. Using ultrafast laser induction technology, we demonstrate that the crystalline state of Ge0.9 Sb0.1 Te can be arbitrarily written and erased, achieving 16 distinct optical levels, which exceeds the 7 levels of Ge2Sb2Te5. In addition, we demonstrated grayscale lithography based on Ge0.9 Sb0.1 Te, proving that Ge0.9 Sb0.1 Te has a broad range of application potential as a visible reconfigurable nanophotonic platform.

Deactivation of Cu/ZnO/Al2O3catalysts in CO2hydrogenation to methanol reaction is one of the main reasons limiting their application. We synthesized a series of La modified Cu/ZnO/Al2O3catalysts by adding different contents of La to improve the stability. In the 100 h short-term stability test at 200 °C under 3 MPa with a GHSV of 12000 mL/(g·h), the unmodified Cu/ZnO/Al2O3catalysts degraded obviously over 100 h. In sharp contrast, the stability was significantly promoted by the addition of La. The best activity was achieved with 5% La added samples (4% CO2conversion and 85% methanol selectivity),which also showed impressive stability over 1000 h except about 17% deactivation during the initial 190−220 h. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results revealed that the addition of 5% La improved the dispersion of Cu and Zn, inhibited the sintering of Cu, stabilized the Cu0/+species and retarded oxidation of Cu in catalysts, which attributed to the high stability of the catalysts.

In this paper, a groundbreaking probe-type fiber optic biosensor, harnessing the surface plasmon resonance (SPR) effect enhanced by barium titanate glass microspheres, is unveiled for virus RNA detection. The multi-physics simulation was used to verify the sensitivity improvement achieved by introducing barium titanate microspheres on the surface of the optical fiber microspheres probe. Experiments confirmed this, pushing the sensor's limit to an impressive 6802 nm/RIU. Biomarker capture on the microsphere surface subtly alters the local refractive index, triggering a detectable SPR spectral shift. To showcase its prowess, the sensor tackled the reverse-transcribed complementary DNA (cDNA) of COVID-19 RNA. Chemical modification of the gold film and DNA hybridization technology ensured specific cDNA detection. The limit of detection for this target reached a remarkable 1.58 nmol/L. This sensor not only excels in virus RNA detection but also holds immense potential for diagnosing major diseases by pinpointing the concentrations of key biomarkers.

Malus toringoides(Rehd.) Hughes, called “Eseye (Ese),” is a traditional medicinal plant from the Tibet province of China that has proven effective in treating cardiac conditions due to its anti-inflammatory, antioxidative, and antiapoptotic properties. In this study, we explored the underlying protective mechanisms of Ese decoction in isoproterenol (ISO)-induced cardiac fibrosis (CF) and established the fact that treatment with an Ese decoction attenuated tissue injury, decreased the release of IL-1β, IL-18, TNF-α, and caspase-3, and elevated the Bax/Bcl-2 ratio in CF mice. We also found that with Ese treatment damage to the mitochondrial ultrastructure of myocardium was alleviated, and the level of reactive oxygen species was markedly diminished. Ese inhibited the expression of proteins associated with pyroptosis by the HK1/NLRP3 signaling pathway and also improved CF. Due to the anti-inflammatory, antioxidative, and antiapoptotic characteristics of Ese decoction, we found that Ese protected against ISO-induced CF, by inhibiting inflammation and pyroptosis as mediated by the HK1/NLRP3 signaling pathway.Graphical AbstractMalus toringoides(Rehd.) Hughes decoction alleviates cardiac fibrosis by inhibiting cardiomyocyte inflammation and pyroptosis.

In critical conduction mode (CRM) totem-pole power factor correction (PFC), the leading phase of the input current caused by input filter capacitance (IFC) current deteriorates the power factor (PF) value for high line frequency (360–800 Hz) grid. In order to improve the PF, either a high-performance microprogrammed control unit (MCU) or the look-up table (LUT) method avoiding the complex cosine calculation is required for direct compensation of IFC current. However, for the purpose of matching the high frequency (360–800 Hz) input voltage and input rms voltage fluctuation ranges, the MCU with large storage capacity is needed to store the LUT data, which increases the cost. In this article, a simple IFC current compensation algorithm by low-cost commercial MCU is proposed without additional external storage components. Furthermore, in order to reduce the current distortion caused by the switching cycle negative current of the inductance, which is generated by the reverse recovery of body diode of mosfet and the resonance between the boost inductance and output junction capacitances of switches, a variable on-time control compensating the negative current of the inductance is proposed. With the proposed control schemes, the input current total harmonics distortion (THD) and PF can meet the RTCADO-160G Std in the high line frequency range in a 300 W CRM totem-pole PFC prototype.