Fatty Amine-Mediated Synthesis of Hierarchical Copper Sulfide Nanoflowers for Efficient NIR-II Photothermal Conversion and Antibacterial Performance.

Non-noble metal photothermal materials have recently attracted increasing attention as unique alternatives to noble metal-based ones due to advantages like earth abundance, cost-effectiveness, and large-scale application capability. In this study, hierarchical copper sulfide (CuS) nanostructures with tunable flower-like morphologies and dimensional sizes are prepared via a fatty amine-mediated one-pot polyol synthesis. In particular, the addition of fatty amines induces a significant decrease in the overall particle size and lamellar thickness, and their morphologies and sizes could be tuned using different types of fatty amines. The dense stacking of nanosheets with limited sizes in the form of such a unique hierarchical architecture facilitates the interactions of the electromagnetic fields between adjacent nanoplates and enables the creation of abundant hot-spot regions, thus, benefiting the enhanced second near-infrared (NIR-II) light absorptions. The optimized CuS nanoflowers exhibit a photothermal conversion efficiency of 37.6%, realizing a temperature increase of nearly 50 °C within 10 min under 1064 nm laser irradiations at a power density of 1 W cm-2. They also exhibit broad-spectrum antibacterial activity, rendering them promising candidates for combating a spectrum of bacterial infections. The present study offers a feasible strategy to generate nanosheet-based hierarchical CuS nanostructures and validates their promising use in photothermal conversion, which could find important use in NIR-II photothermal therapy.

Microplastics footprint in nature reserves-a case study on the microplastics in the guano from Yancheng Wetland Rare Birds National Nature Reserve, China.

Bio-ingestion of microplastics poses a global threat to ecosystems, yet studies within nature reserves, crucial habitats for birds, remain scarce despite the well-documented ingestion of microplastics by avian species. Located in Jiangsu Province, China, the Yancheng Wetland Rare Birds Nature Reserve is home to diverse bird species, including many rare ones. This study aimed to assess the abundance and characteristics of microplastics in common bird species within the reserve, investigate microplastic enrichment across different species, and establish links between birds' habitat types and microplastic ingestion. Microplastics were extracted from the feces of 110 birds, with 84 particles identified from 37.27% of samples. Among 8 species studied, the average microplastic abundance ranged from 0.97 ± 0.47 to 43.43 ± 61.98 items per gram of feces, or 1.5 ± 0.87 to 3.4 ± 1.50 items per individual. The Swan goose (Anser cygnoides) exhibited the highest microplastic abundance per gram of feces, while the black-billed gull (Larus saundersi) had the highest abundance per individual. The predominant form of ingested microplastics among birds in the reserve was fibers, with polyethylene being the most common polymer type. Significant variations in plastic exposure were observed among species and between aquatic and terrestrial birds. This study represents the first quantitative assessment of microplastic concentrations in birds within the reserve, filling a crucial gap in research and providing insights for assessing microplastic pollution and guiding bird conservation efforts in aquatic and terrestrial environments.

Fabrication of Gold-Based "Sphere-on-Plate" Hybrid Nanostructures with Dual Plasmonic Absorptions Covering Visible and Near-Infrared II Windows via the Volmer-Weber Growth Mode.

We report a synthetic strategy to create gold(Au)-based "sphere-on-plate" hybrid nanostructures (SPHNSs). The surface doping of plate-like Au seeds with Pt/Ag atoms is found to be crucial to increase the lattice spacing, inducing island-like deposition of Au atoms via the Volmer-Weber growth mode. The resulting products are featured with the morphology that quasi-spherical nanoparticles are scattered over the nanoplates. Due to the presence of two distinctly dimensioned particles in one entity, the current Au-based SPHNSs exhibit unique dual plasmonic absorptions, where the visible absorbance centered at 546 nm is related to the size of the anchored particles. Arising from such a plasmonic advantage, the Au-based SPHNSs exhibit enhancement in photothermal conversion under laser irradiations at the wavelengths of both 808 and 1064 nm. The current work offers a feasible route to fabricate noble metal hybrid nanostructures involving zero-dimensional (0D) and two-dimensional (2D) structures, which could work as promising materials for photothermal conversion.

Smartphone-based colorimetric assay of antioxidants in red wine using oxidase-mimic MnO2 nanosheets.

In this work, we report a fast and colorimetric method for the detection of antioxidants based on the oxidase-like activity of two-dimensional MnO2 nanosheets. Specifically, MnO2 nanosheets can transform the colourless substrate, 3,3',5,5'-tetramethylbenzidine (TMB), into a deep blue product (oxTMB) via catalytic oxidation, with a specific absorption peak arising at 652 nm. In the presence of antioxidants, both the dramatic colour fading and the decrease in absorbance at 652 nm are observed owing to the inhibition of catalytic oxidation of TMB, where MnO2 nanosheets can be transformed into Mn2+ with the aid of antioxidants. Based on the linear relationship between the absorbance at 652 nm and the concentration of the antioxidants, quantitative determination of antioxidants in the range of 0.1-12 µM has been achieved. Moreover, combined with smartphone-based technology, a portable colorimetric analytical platform for assay of antioxidants is further developed. This method shows advantages including easy operation, low cost, rapid detection and high sensitivity and has been successfully applied in the determination of total antioxidants in red wine.

A numerical coupling method for particle tracking in electromagnetic fields.

With the arrival of the information age, the electromagnetic energy in space increases constantly, resulting in the influence of electromagnetic waves on the charged aerosol particles in the environment which should be taken into account. Here, a numerical coupling method based on temporal and spatial scales is proposed to solve the difficulty in obtaining the trajectory of particles under the action of high-frequency electromagnetic waves. In the temporal scale, two constant forces with linear relationship are used to equilibrate the electromagnetic field forces under different conditions, however the above-mentioned equivalent method has the space limitation; in addition, on the spatial scale, the model with larger geometry should be divided into multiple basic modules spatially, the domain division method is adopted and due to the above method it can be used well in the basic module. Verified the correctness through the comparison of the results, and compared with the traditional method, the above method greatly reduces the computational complexity. Some interesting results were obtained by calculating the modulated waves with the above method, which indicate that special forms of electromagnetic waves will significantly affect the motion of particles.

[Study on Extraction Methods of Characteristic Wavelength of Visible Near Infrared Spectroscopy Used for Sugar Content of Hetao Muskmelon].

Hetao muskmelon is a unique fruit in the hetao area of northwest china, which has been loved by consumers. Sugar content is the important indicator of measuring the quality and mature of muskmelons. This research uses Maya 2000 pro portable spectrometer and PR-101α portable digital refractometer to get spectrum and sugar content values of "jinhongbao" muskmelon, researches the effect of different extraction methods of characteristic wavelength (stepwise multiple linear regression (SMLR), interval partial least squares(iPLS), backward interval partial least squares (biPLS) and synergy interval partial least squares (siPLS)) on model accuracy and prediction results. The results show: using biPLS method on extraction of characteristic wavelength will the full spectrum evenly divided into 20 subintervals, the PLS factors of 14, when removing 8 subintervals, and choosing the wavelength variable numbers of 218, getting the biPLS model is best, RMSE of corresponding calibration and prediction models is 0.9961 and 1.18. So using the biPLS method of extraction on spectrum wavelength could extract effectively the characteristic wavelengths of melon sugar content, increase the ability of model prediction, and achieve rapid detecting of sugar content about muskmelons.

'Moko' drums and gongs, ritual musical instruments and local currency from Alor Island, Southeast Indonesia: A comprehensive and verified lexical data set.

This paper provides comprehensive and systematized lists of names of 'moko' drums from Alor Island, in Southeast Indonesia. 'Moko' drums are unique cultural objects from the Alor-Pantar Archipelago and, besides their ancient function of ritual instruments used mainly for religious purposes and in public events by the indigenous peoples of the islands, they represented and still are considered a very valuable local 'currency' for trade and for specific social interactions rooted in aboriginal culture, like bride price negotiations. Despite the fact that they are extremely popular and widespread among Papuan peoples in Alor and Pantar, the origins of these drums are still relatively obscure. The native speakers, indeed, cannot explain the name 'moko' in itself, at the etymological and semantic level, and, despite the fact that they agree upon non-local origins of the instruments, they do not know where the instruments themselves were produced and from where they came to the islands. Our paper provides the readers with comprehensive lists that systematically collect the names of the drums, with the related glosses and basic additional information, from three representative Papuan languages of Alor Island, namely Abui, Sawila, and Kula. Configured as potentially indispensable tools to develop further research, these lists enhance our knowledge and understanding of the culture of the 'moko' drums in the Alor-Pantar Archipelago, at the linguistic (etymology of the names), anthropological (social value of the drums), and archeological (typology and provenance of the instruments) levels. This cataloguing operation is also part of the effort of documentation of the languages and cultures, still scarcely documented and definitely endangered, of the native peoples of the Alor-Pantar Archipelago.

M1 Macrophage-Targeted Curcumin Nanocrystals with l-Arginine-Modified for Acute Lung Injury by Inhalation.

Acute Lung Injury/Acute Respiratory Distress Syndrome (ALI/ARDS) with clinical manifestations of respiratory distress and hypoxemia remains a significant cause of respiratory failure, boasting a persistently high incidence and mortality rate. Given the central role of M1 macrophages in the pathogenesis of acute lung injury (ALI), this study utilized the anti-inflammatory agent curcumin as a model drug. l-arginine (L-Arg) was employed as a targeting ligand, and chitosan was initially modified with l-arginine. Subsequently, it was utilized as a surface modifier to prepare inhalable nano-crystals loaded with curcumin (Arg-CS-Cur), aiming for specific targeting of pulmonary M1 macrophages. Compared with unmodified chitosan-curcumin nanocrystals (CS-Cur), Arg-CS-Cur exhibited higher uptake in vitro by M1 macrophages, as evidenced by flow cytometry showing the highest fluorescence intensity in the Arg-CS-Cur group (P < 0.01). In vivo accumulation was greater in inflamed lung tissues, as indicated by small animal imaging demonstrating higher lung fluorescence intensity in the DiR-Arg-CS-Cur group compared to the DiR-CS-Cur group in the rat ALI model (P < 0.05), peaking at 12 h. Moreover, Arg-CS-Cur demonstrated enhanced therapeutic effects in both LPS-induced RAW264.7 cells and ALI rat models. Specifically, treatment with Arg-CS-Cur significantly suppressed NO release and levels of TNF-α and IL-6 in RAW264.7 cells (p < 0.01), while in ALI rat models, expression levels of TNF-α and IL-6 in lung tissues were significantly lower than those in the model group (P < 0.01). Furthermore, lung tissue damage was significantly reduced, with histological scores significantly lower than those in the CS-Cur group (P < 0.01). In conclusion, these findings underscore the targeting potential of l-arginine-modified nanocrystals, which effectively enhance curcumin concentration in inflammatory environments by selectively targeting M1 macrophages. This study thus introduces novel perspectives and theoretical support for the development of targeted therapeutic interventions for acute inflammatory lung diseases, including ALI/ARDS.

Two-dimensional ß-MnOOH nanosheets with high oxidase-mimetic activity for smartphone-based colorimetric sensing.

Manganese (Mn) is a versatile transition element with diverse oxidation states and significant biological importance. Mn-based nanozymes have emerged as promising catalysts in various applications. However, the direct use of manganese oxides as oxidase mimics remains limited and requires further improvement. In this study, we focus on hydroxylated manganese (MnOOH), specifically the layered form ß-MnOOH which exhibits unique electronic and structural characteristics. The two-dimensional ß-MnOOH nanosheets were synthesized through a hydrothermal approach and showed remarkable oxidase-like activity. These nanosheets effectively converted the oxidase substrate, 3,3',5,5'-tetramethylbenzidine (TMB), into its oxidized form by initiating the conversion of dissolved oxygen into ·O2-, 1O2 and ·OH. However, in the presence of L-cysteine (L-Cys), the catalytic activity of ß-MnOOH was significantly inhibited, enabling highly sensitive detection of L-Cys. This sensing strategy was successfully applied for smartphone-based L-Cys assay, offering potential utility in the diagnosis of Cys-related diseases. The exploration of layered ß-MnOOH nanosheets as highly active oxidase mimics opens up new possibilities for catalytic and biomedical applications.

Inhalation of L-arginine-modified liposomes targeting M1 macrophages to enhance curcumin therapeutic efficacy in ALI.

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), characterized by uncontrolled lung inflammation, is one of the most devastating diseases with high morbidity and mortality. As the first line of defense system, macrophages play a crucial role in the pathogenesis of ALI/ARDS. Therefore, it has great potential to selectively target M1 macrophages to improve the therapeutic effect of anti-inflammatory drugs. l-arginine plays a key role in regulating the immune function of macrophages. The receptors mediating l-arginine uptake are highly expressed on the surface of M1-type macrophages. In this study, we designed an l-arginine-modified liposome for aerosol inhalation to target M1 macrophages in the lung, and the anti-inflammatory drug curcumin was encapsulated in liposomes as model drug. Compared with unmodified curcumin liposome (Cur-Lip), l-arginine functionalized Cur-Lip (Arg-Cur-Lip) exhibited higher uptake by M1 macrophages in vitro and higher accumulation in inflamed lungs in vivo. Furthermore, Arg-Cur-Lip showed more potent therapeutic effects in LPS-induced RAW 264.7 cells and the rat model of ALI. Overall, these findings indicate that l-arginine-modified liposomes have great potential to enhance curcumin treatment of ALI/ARDS by targeting M1 macrophages, which may provide an option for the treatment of acute lung inflammatory diseases such as coronavirus disease 2019 (COVID-19), severe acute respiratory syndrome and middle east respiratory syndrome.

Molecular dynamics simulation of water condensation with nucleus under electromagnetic wave irradiation.

The condensation process of water with different nuclei under electromagnetic wave irradiation was studied by molecular dynamics simulation. It was found that there is a different electric-field effect when the condensation nucleus was a small (NH4)2SO4 cluster than a CaCO3 nucleus. Through the analysis of the hydrogen-bond number, energy change, and dynamic behavior, we found that the effect of external electric field on the condensation process mainly comes from the change of potential energy caused by the dielectric response and there is a competition effect between the dielectric response and the dissolution in the system with (NH4)2SO4.

Reversible regulation of enzyme-like activity of molybdenum disulfide quantum dots for colorimetric pharmaceutical analysis.

Regulating the catalytic activity of nanozymes is significant for their applications in various fields. Here, we demonstrate a new strategy to achieve reversible regulation of the nanozyme's activity for sensing purpose. This strategy involves the use of zero-dimensional MoS2 quantum dots (MQDs) as the building blocks of nanozymes which display very weak peroxidase (POD)-like activity. Interestingly, such POD-like activity of the MQDs largely enhances in the presence of Fe3+ while diminishes with the addition of captopril thereafter. Further investigations identify the mechanism of Fe3+-mediated aggregation-induced enhancement of the POD-like activity and the inhibitory effect of captopril on the enhancement, which is highly dependent on their concentrations. Based on this finding, a colorimetric method for the detection of captopril is developed. This sensing approach exhibits the merits of simplicity, rapidness, reliability, and low cost, which has been successfully applied in quality control of captopril in pharmaceutical products. Moreover, the present sensing platform allows smartphone read-out, which has promising applications in point-of-care testing devices for clinical diagnosis and drug analysis.

Enhanced Peroxidase-like Activity of CuS Hollow Nanocages by Plasmon-Induced Hot Carriers and Photothermal Effect for the Dual-Mode Detection of Tannic Acid.

High catalytic activity is one of the necessary parameters for nanozymes to substitute for natural enzymes. It remains a great challenge to improve the specific enzyme-like activity of nanozymes as much as possible using the characteristics of nanomaterials for avoiding complexity and introducing additional uncertainties. Here, by combining the peroxidase (POD)-like activity and plasmon properties of CuS hollow nanocages (CuS HNCs), we demonstrate the feasibility of modulating the catalytic activity of nanozymes by the localized surface plasmon resonance (LSPR) effect. Rough surfaces and hollow-cage structures endow CuS HNCs with abundant hot spots to produce strong LSPR in the near-infrared (NIR) region, which makes the CuS HNCs simultaneously generate plentiful high-energy hot carriers and thermal effect to mediate H2O2 cleavage to yield the reactive oxide species (ROS) as well as speed up the reaction, leading to a dramatically enhanced POD-like activity. Based on the light-enhanced catalytic activity and high photothermal efficiency of the reaction system, a dual-mode strategy for detecting tannic acid (TA) is developed and successfully applied to determine the content of TA in different kinds of teas. This work not only provides a novel path for tuning the specific enzyme-like activity of nanomaterials but also shows a perspective for dual-mode sensing based on a photoinduced plasmon-enhanced effect.

Functionalized Mn3 O4 Nanosheets with Photothermal, Photodynamic, and Oxidase-Like Activities Triggered by Low-Powered Near-Infrared Light for Synergetic Combating Multidrug-Resistant Bacterial Infections.

Multidrug-resistant (MDR) pathogenic bacterial infections have become a major danger to public health. Synergetic therapy through multiple approaches is more powerful than the respective one alone, but has been rarely achieved in defeating MDR bacterial infections so far. Herein, indocyanine green-functionalized Mn3 O4 nanosheets are engineered as an efficient and safe antibacterial agent with photothermal, photodynamic, and oxidase-like activities, which display powerful ability in treating MDR bacterial infections. Therein, photothermal and photodynamic activities can be triggered by a single low-powered near-infrared laser (808 nm, 0.33 W cm-2 ), resulting in the generation of localized hyperthermia (photothermal conversion efficiency, 67.5%) and singlet oxygen. Meanwhile, oxidase-like activity of this material further leads to the generation of hydroxyl radical as well as superoxide radical. Sheet-like structure with rough surfaces make them tends to adhere on bacterial surface and thus damage membrane system as well as influence bacterial metabolism. As a result, Gram-positive and Gram-negative bacteria can both be eradicated. Animal experiments further indicate that the functionalized Mn3 O4 nanosheets can effectively treat methicillin-resistant Staphylococcus aureus-infected wounds through the triple synergetic therapy. Moreover, toxicity evaluation in vitro and in vivo has proved the superior biosafety of this material, which is promising to apply in clinical anti-infective therapy.

Reconfigurable all-dielectric metasurface based on tunable chemical systems in aqueous solution.

Dynamic control transmission and polarization properties of electromagnetic (EM) wave propagation is investigated using chemical reconfigurable all-dielectric metasurface. The metasurface is composed of cross-shaped periodical teflon tubes and inner filled chemical systems (i.e., mixtures and chemical reaction) in aqueous solution. By tuning the complex permittivity of chemical systems, the reconfigurable metasurface can be easily achieved. The transmission properties of different incident polarized waves (i.e., linear and circular polarization) were simulated and experimentally measured for static ethanol solution as volume ratio changed. Both results indicated this metasurface can serve as either tunable FSS (Frequency Selective Surface) or tunable linear-to-circular/cross Polarization Converter at required frequency range. Based on the reconfigurable laws obtained from static solutions, we developed a dynamic dielectric system and researched a typical chemical reaction with time-varying permittivity filled in the tubes experimentally. It provides new ways for realizing automatic reconfiguration of metasurface by chemical reaction system with given variation laws of permittivity.