Search Results (4,133)

In this review we present a comprehensive overview of the published literature related to the use of Hybrid Cooperative Complexes (HCCs) of low- and high-molecular-weight hyaluronic acid in aesthetic medicine. HCCs have been developed to overcome the shortcomings of traditional hyaluronic based dermal fillers. Specifically, HCCs deliver both high- and low-molecular-weight hyaluronic acid (HA), maximizing their complementary effects. They are biocompatible and formulated without the addition of foreign agents. Cooperative hydrogen bonds extend their durability and make them more resistant to hyaluronidase compared to high-molecular-weight HA. The rheological properties of HCC formulations allow for easy exertion through the needle and diffusion in the tissue compared to high-molecular-weight HA alone. In vitro studies have shown that HCCs improve vitality of fibroblasts, keratinocytes and adipocytes, and stimulate production of collagen and elastin. Studies on scratched co-cultures of immortalized human keratinocytes and human dermal fibroblasts demonstrated that HCCs accelerate wound closure. Furthermore, HCCs delayed senescence of mesenchymal stromal cells to a greater extent than high-molecular-weight HA or low-molecular-weight HA alone. Clinical studies show a reduction in wrinkle severity, improvement in skin roughness profile and reduction of skin laxity with pronounced improvement in superficial skin hydration lasting up to 6 months. The formulation intended for restoration of fat compartments demonstrated reduction in cheek volume loss and improvement in skin thickness. Subjects report moderate-to-high satisfaction and are likely to recommend the treatment. Limitations of the published studies are also addressed, as well as reported adverse events and published safety data. Full article

This study examines the structural evolution of Knowledge Innovation Networks (KINs) and Technology Innovation Networks (TINs) across Chinese cities (2015–2024). Using SCI/SSCI co-authorship and prefecture-level patent data, we construct dual-layer networks and assess their resilience through metrics such as average clustering coefficient, path length, global efficiency, and largest-component ratio. Our framework clarifies how network structure, spatial proximity, and urban hierarchy jointly shape innovation dynamics and opportunity distribution. Three main findings emerge. First, KINs have moved toward polycentricity yet remain hierarchically rigid, with persistent core–periphery gaps despite improved connectivity in tier 2–4 cities. TINs show greater cross-tier adaptability, creating new innovation gateways while intensifying intra-tier polarization. Second, under simulated disruptions, KINs are vulnerable to targeted attacks and exhibit path-dependent degradation, whereas TINs maintain efficiency until a critical threshold, then collapse abruptly. Third, MRQAP analysis reveals that economic and geographic proximity facilitate collaboration in KIN but constrain linkages in TINs, with spatial proximity exerting a stronger influence on knowledge flows. These results demonstrate how innovation networks mediate urban–rural interactions, affect spatial inequality, and shape regional resilience. We argue for differentiated policies that strengthen core–periphery connectivity while mitigating proximity-induced lock-in, fostering more inclusive, resilient, and sustainable urban innovation systems. Full article

The increasing impact of global warming is predominantly driven by the extensive use of fossil fuels, which release significant amounts of greenhouse gases into the atmosphere. This has led to a critical need for alternative, sustainable energy sources that can mitigate environmental impacts. Photovoltaic technology has emerged as a promising solution by harnessing renewable energy from the sun, providing a clean and inexhaustible power source. Perovskite solar cells (PSCs) are a class of hybrid organic–inorganic solar cells that have recently attracted significant scientific attention due to their low cost, relatively high efficiency, low–temperature processing routes, and longer carrier lifetimes. These characteristics make them a viable alternative to traditional fossil fuels, reducing the carbon footprint and contributing to the fight against global warming. In this study, the SCAPS–1D numerical simulator was used in the computational analysis of a PSC device with the configuration FTO/ETL/BaZr(S_0.6Se_0.4)₃/HTL/Ir. Different hole transport layer (HTL) and electron transport layer (ETL) material were proposed and tested. The HTL materials included copper (I) oxide (Cu₂O), 2,2′,7,7′–Tetrakis(N,N–di–p–methoxyphenylamine)9,9′–spirobifluorene (spiro–OMETAD), and poly(3–hexylthiophene) (P₃HT), while the ETLs included cadmium suphide (CdS), zinc oxide (ZnO), and [6,6]–phenyl–C₆₁–butyric acid methyl ester (PCBM). Finally, BaZr(S_0.6Se_0.4)₃ was proposed as an absorber, and a fluorine–doped tin oxide glass substrate (FTO) was proposed as an anode. The metal back contact used was iridium. Photovoltaic parameters such as short circuit density (I_sc), open circuit voltage (V_oc), fill factor (FF), and power conversion efficiency (PCE) were used to evaluate the performance of the device. The initial simulated primary device with the configuration FTO/CdS/BaZr(S_0.6Se_0.4)₃/spiro–OMETAD/Ir gave a PCE of 5.75%. Upon testing different HTL materials, the best HTL was found to be Cu₂O, and the PCE improved to 9.91%. Thereafter, different ETLs were also inserted and tested, and the best ETL was established to be ZnO, with a PCE of 10.10%. Ultimately an optimized device with a configuration of FTO/ZnO/BaZr(S_0.6Se_0.4)₃/Cu₂O/Ir was achieved. The other photovoltaic parameters for the optimized device were as follows: FF = 31.93%, J_sc = 14.51 mA cm⁻², and V_oc = 2.18 V. The results of this study will promote the use of environmentally benign BaZr(S_0.6Se_0.4)₃–based absorber materials in PSCs for improved performance and commercialization. Full article

To address the decline in self-consistency and limited spatial adaptability of traditional interpolation methods in complex terrain, this study proposes a terrain-constrained Triangulated Irregular Network (TIN) interpolation method based on UAV point clouds. The method was tested in the southern margin of the Lufeng Dinosaur National Geopark, Yunnan Province, using ground points at different sampling densities (90%, 70%, 50%, 30%, and 10%), and compared with Spline, Kriging, ANUDEM, and IDW methods. Results show that the proposed method maintains the lowest RMSE and MAE across all densities, demonstrating higher stability and self-consistency and better preserving terrain undulations. This provides technical support for high-precision DEM reconstruction from UAV point clouds in complex terrain. Full article

As a core candidate material for indium-free transparent conductive oxides, tin dioxide (SnO₂) thin films are gradually replacing indium tin oxide (ITO) and becoming a research focus in the field of optoelectronic devices, thanks to their excellent physicochemical stability, wide bandgap characteristics, and abundant tin resource reserves. This review focuses on SnO₂ thin films. Firstly, it elaborates on the tetragonal rutile crystal structure characteristics of SnO₂ and the transparent conductive mechanism based on oxygen vacancies and doping elements to regulate free electron concentration, while clarifying the key parameters for evaluating their transparent conductive properties. Subsequently, it systematically summarizes the research progress in preparing SnO₂ transparent conductive thin films via physical methods and chemical methods in recent years. It compares the microstructure and transparent conductive properties of thin films prepared by different methods, and analyzes the regulatory laws of preparation processes, doping types, and film thickness on their optoelectronic properties. Furthermore, this work supplements the current application status of SnO₂ thin films in devices. Meanwhile, the core performance differences between indium-free tin-based thin film devices and ITO-based devices are compared. Finally, we have summarized the advantages and challenges of physical and chemical methods in the preparation of SnO₂ thin films. It also forecasts the application potential of interdisciplinary integration of physical–chemical methods and the development of new doping systems in the preparation of high-performance SnO₂ transparent conductive thin films. This review aims to provide theoretical guidance and technical references for the selection and process optimization of SnO₂ transparent conductive thin films in fields such as photovoltaic devices and flexible optoelectronic equipment. Full article

This essay examines how contemporary Anglophone Chinese women writers rewrite the imagery of Chinese snake women through speculative retellings that foreground sisterhood, queer desire, and diasporic identity. Drawing on queer diaspora studies and feminist criticism, I argue that Larissa Lai’s Salt Fish Girl (2002) and Amanda Lee Koe’s Sister Snake (2024) revise the figure of the Chinese snake woman to imagine forms of female intimacy and kinship that transcend heteronormative and patriarchal frameworks. In these works, sisterhood operates both as a familial bond and as an intimate, queer relation charged with affective, physical, and occasionally erotic intensity. The original White Snake legend—one of China’s Four Great Folktales—has long invited queer readings, especially through the complex relationship between White Snake and her companion Green Snake. In dialogue with the Chinese snake myth, Lai and Koe relocate the snake woman into speculative worlds shaped by queer desire, racial marginalization, and transnational migration. In Salt Fish Girl, Lai reimagines the reincarnations of the half-snake Chinese mother goddess Nu Wa across colonial South China and near-future bio-capitalist Canada, portraying a cross-temporal lesbian love between the protagonist and the titular Salt Fish Girl. In Sister Snake, Koe’s protagonists—serpent sisters Su and Emerald, separated between Singapore and New York—disrupt normative family scripts while forging a fragmented but enduring affective bond. Through the motif of the Chinese snake woman, these works construct imaginative spaces in which intimate sisterhood subverts patriarchal and national containment, advancing a queer vision of female togetherness. Full article

This work presents the design of a novel electrochemical sensor for highly sensitive determination of LEV, utilizing a sensing platform based on a newly synthesized, high-purity manganese (III) porphyrin complex [5,10,15,20-tetrayltetrakis(2-methoxybenzene-4,1-diyl) tetraisonicotinateporphyrinato] manganese (III) porphyrin (MnTMIPP). The successful synthesis of the MnTMIPP complex was verified using ultraviolet–visible (UV–Vis) and infrared spectroscopy (IR). The sensing electrode was fabricated by depositing the synthesized material onto an indium tin oxide (ITO) electrode via a drop-coating method. Under optimized experimental conditions, the proposed sensor demonstrated a wide dynamic range, from 10⁻⁹ M to 10⁻³ M, with a low calculated detection limit of 4.82 × 10⁻¹⁰ M. Furthermore, the MnTMIPP/ITO electrode displayed interesting metrological performance: high selectivity, reproducibility, and stability. Successful application in spiked river water and saliva samples with satisfactory recovery rates confirms the sensor’s potential as a reliable and cost-effective platform for monitoring LEV in real-world environments. Full article

Transparent conductive materials (TCMs) are essential for optoelectrical devices ranging from smart windows and defogging films to soft sensors, display technologies, and flexible electronics. Materials, such as indium tin oxide (ITO) and silver nanowires (AgNWs), are commonly used and offer high optical transmittance and electrical conductivity, but suffer from brittleness, oxidation susceptibility, and require high-cost materials, greatly limiting their use. Carbon nanotube (CNT) networks provide a promising alternative, featuring mechanical compliance, chemical robustness, and scalable processing. This study reports an aqueous ink formulation composed of ultra-long mix-walled carbon nanotubes (UL-CNTs), compatible with the flow coating process, yielding uniform transparent conductive films (TCFs) on polyethylene terephthalate (PET), glass, and polycarbonate (PC). The resulting films exhibit tunable transmittance (85%–88% for single layers; ~57% for three layers at 550 nm) and sheet resistance of 7.5 kΩ/□ to 1.5 kΩ/□ accordingly. These TCFs maintain stable sheet resistance for over 5000 bending cycles and show excellent mechanical durability with negligible effects on heating performance. Post-deposition treatments, including nitric acid vapor doping or flash photonic heating (FPH), further reduce sheet resistance by up to 80% (7.5 kΩ/□ to 1.2 kΩ/□). X-ray photoelectron spectroscopy (XPS) results in reduced surface oxygen content after FPH. The photonic-treated heaters attain ~100 °C within 20 s at 100 V. This scalable, water-based process provides a pathway toward low-cost, flexible, and stretchable devices in a variety of fields, including printed electronics, optoelectronics, and thermal actuators. Full article

Transparent conductive films based on silver nanowire meshes have demonstrated significant potential as alternatives to conventional tin-doped indium oxide and fluorine-doped tin oxide thin films. However, these materials feature high junction resistance, poor damp heat (DH) stability, and weak mechanical adhesion to substrates, which are critical issues that must be addressed before any practical applications. In this paper, transparent conducting films composed of silver nanowire (AgNW) frameworks and amorphous indium zinc oxide (IZO) fillers were prepared by a spin-coating method. The AgNW-IZO composite films exhibited a higher conductivity and better DH stability and adhesion to substrates than that of their constituent parts alone. The lowest sheet resistance of the composite films was 3.3 ohm/sq with approximately 70% transparency in the visible spectrum. No degradation was observed after 8 months. The excellent DH stability and mechanical adhesion might facilitate applications of these AgNW-IZO composite films in optoelectronic devices. Furthermore, the composite electrode is shown to have potential as a transparent heater. Full article

With the rapid advancement of detection technologies, traditional static electromagnetic absorbers increasingly struggle to meet controllable stealth requirements across diverse dynamic environments. To achieve active and controllable modulation of electromagnetic reflection characteristics, this paper proposes a transparent reconfigurable metamaterial absorber based on an origami structure. By adjusting the folding angles of the indium tin oxide (ITO)-polyethylene terephthalate (PET) film, the structure achieves reversible deformation from the vertical state to the horizontal state. This enables continuous modulation of the reflectance from below −10 dB (absorbing state) to nearly 0 dB (reflecting state) within the 4–18.9 GHz frequency range, with a relative bandwidth exceeding 130% and excellent angular stability. The energy loss and current distribution under different states are analyzed, revealing the mechanisms behind broadband absorption and deep modulation. Experimental measurements of the fabricated metamaterial align well with simulation results. Leveraging its flexible structure, reversible modulation capability, and angular stability, this origami-inspired reconfigurable metamaterial demonstrates promising application potential in the fields of adaptive electromagnetic camouflage and stealth protection. Full article

Electron transport measurements on Co/TiN multilayers are employed to explore the effect of TiN layers on Co resistivity. For this, 50 nm thick multilayer stacks containing N = 1–10 individual Co layers that are separated by 1 nm thick TiN layers are sputter deposited on SiO₂/Si(001) substrates at 400 °C. X-ray diffraction and reflectivity measurements indicate a tendency for a 0001 preferred orientation, an X-ray coherence length of 13 nm that is nearly independent of N, and an interfacial roughness that increases with N. The in-plane multilayer resistivity ρ increases with increasing N = 1–10, from ρ = 14.4 to 36.6 µΩ-cm at room temperature and from ρ = 11.2 to 19.4 µΩ-cm at 77 K. This increase is due to a combination of increased electron scattering at interfaces and grain boundaries, as quantified using a combined Fuchs–Sondheimer and Mayadas–Shatzkes model. The analysis indicates that a decreasing thickness of the individual Co layers d_Co from 50 to 5 nm causes not only an increasing resistivity contribution from Co/TiN interface scattering (from 9 to 88% with respect to the room-temperature bulk resistivity) but also an increasing (39 to 154%) grain boundary scattering contribution, which exacerbates the resistivity penalty due to the TiN liner. These results are supported by Co/TiN bilayer and trilayer structures deposited on Al₂O₃ (0001) at 600 °C. Interfacial intermixing causes Co₂Ti and Co₃Ti alloy phase formation, an increase in the contact resistance, a degradation of the Co crystalline quality, and a 2.3× higher resistivity for Co deposited on TiN than Co directly deposited on Al₂O₃(0001). The overall results show that TiN liners cause a dramatic increase in Co interconnects due to diffuse surface scattering, interfacial intermixing/roughness, and Co grain renucleation at Co/TiN interfaces. Full article

In this study, the integration of SnO₂ with a perfluorinated Zn(II) porphyrin derivative, namely ZnTPPF₂₀CN, was explored as a strategy to enhance the performance of chemoresistive sensors toward gaseous acetone detection. The ZnTPPF₂₀CN molecule was specifically designed with an ethynylphenyl-cyanoacrylic anchoring group and a benzothiadiazole (BTD) spacer, enabling its chemisorption onto the SnO₂ surface. Hybrid materials containing three different ZnTPPF₂₀CN-to-SnO₂ ratios (1:4, 1:32, 1:64) were fabricated and tested for acetone detection at 120 °C, both under dark conditions and LED illumination. The sensing behavior of these hybrids was compared with that of previously studied SnO₂ composites, incorporating physisorbed, unsubstituted ZnTPPF₂₀. Among the tested ratios, the 1:32 ZnTPPF₂₀CN/SnO₂ demonstrated superior acetone sensitivity compared to its unmodified counterpart, despite showing a lower intrinsic conductivity in air and a reduced electron transfer efficiency. Density functional theory (DFT) calculations provided insights into the possible anchoring modes and interfacial electronic interactions, helping to rationalize this counterintuitive observation. The enhanced sensing response was attributed to a more favorable balance between charge injection and the availability of SnO₂ electronic states, facilitated by the chemisorbed anchoring of ZnTPPF₂₀CN. Overall, our findings highlight the importance of molecular engineering, particularly in terms of molecular design, loading ratio, and anchoring mechanism, in modulating charge dynamics and optimizing the sensing efficiency of porphyrin/SnO₂ nanocomposites. Full article

Tungsten oxide (WO₃) nanostructures have emerged as promising electroactive materials due to their high pseudocapacitance, structural versatility, and chemical stability, while reduced graphene oxide (rGO) provides excellent electrical conductivity and surface area. The strategic combination of these nanomaterials in hybrid electrodes has gained attention for enhancing the energy storage performance of supercapacitors. In this work, we report the fabrication and electrochemical performance of nanostructured multilayer films based on the electrostatic Layer-by-Layer (LbL) self-assembly of poly (amidoamine) (PAMAM) dendrimers alternated with tungsten oxide (WO₃) nanofibers dispersed in reduced graphene oxide (rGO). The films were deposited onto indium tin oxide (ITO) substrates and subsequently subjected to electrochemical reduction. UV-Vis spectroscopy confirmed the linear growth of the multilayers, while atomic force microscopy (AFM) revealed homogeneous surface morphology and thickness control. Electrochemical characterization by cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) revealed a predominantly electrical double-layer capacitive (EDLC) behavior. From the GCD measurements (PAMAM/rGO-WO₃)₂₀ films achieved an areal capacitance of ≈2.20 mF·cm⁻², delivering an areal energy density of ≈0.17 µWh·cm⁻² and an areal power density of ≈2.10 µW·cm⁻², demonstrating efficient charge storage in an ultrathin electrode architecture. These results show that the synergistic integration of PAMAM dendrimers, reduced graphene oxide, and WO₃ nanofibers yields a promising strategy for designing high-performance electrode materials for next-generation supercapacitors. Full article

Photoluminescence studies of single-crystalline SnO₂ grown by chemical vapor transport from SnCl₄ and H₂O vapors were carried out in the visible spectral range. A non-trivial dependence of the 2.6 eV emission band on temperature and optical excitation level was observed. Based on the obtained data, the ionization energy of a shallow donor in SnO₂ was estimated to be 7 meV. Additionally, a model of energy levels and radiative transitions associated with shallow donors and intrinsic defects is proposed. Full article