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Recalcitrant pollutants are challenging to degrade during water treatment processes. Methylene blue (MB), a cationic dye, is particularly resistant to degradation and is environmentally persistent. Heterogeneous photocatalysis has emerged as a suitable strategy for removing such pollutants from water. In this work, ZrO2 thin films were modified with Anderson-type Mn-polyoxometalate (MnPOM) ((NH4)3[MnMo6O24H6]), and the efficiency of MB removal from water was studied. ZrO2 was synthesized by a sol–gel method, with thin films deposited using the doctor blade method, and ZrO2 thin films were modified using chemisorption method. The synthesized materials were characterized using SEM, EDX, UV-Vis diffuse reflectance spectroscopy and FTIR. The adsorption kinetics and isotherms for MB were studied for both bare ZrO2 and ZrO2/MnPOM composites. Optical characterization showed a band gap energy of 4.02 eV for bare ZrO2, while the ZrO2/MnPOM composite exhibited a band gap of 3.7 eV. Furthermore, ZrO2 showed lower MB removal capacity (∼8%) than ZrO2/MnPOM thin films (∼29%). The isothermal adsorption studies indicated that MB adsorption onto both bare ZrO2 and ZrO2/MnPOM followed the Langmuir adsorption model (qm = 20.6 mg g−1 for ZrO2 and qm = 62.9 mg g−1 for ZrO2/MnPOM). Furthermore, the adsorption kinetics of MB were well described by a pseudo-second-order model. Photocatalytic testing under UV irradiation showed an apparent rate constant (kap) of 2 × 10−3 min−1 for bare ZrO2 and a value of kap 5.4 × 10−3 min−1 for ZrO2/MnPOM after 100 minutes. TD-DFT calculations revealed an LMCT interaction between the ZrO2 nanoparticle and the MnPOM, which likely contributes to the enhanced photocatalytic activity of the ZrO2/MnPOM composite. [ABSTRACT FROM AUTHOR]

This work focused to engineering double perovskite (DP) La2NiMnO6 (LNMO) nanoparticles (NPs) through the co-precipitation method and further calcined at 1000 °C. The flexibility in the multi-element structure of LNMO as a single-component system has been utilized to see the synergetic effect by tuning the band gap and hence redox potentials of radicals, which in turn enhances the electron and hole separation, and production of radicals, thus improving the efficacy of a photocatalyst. XRD confirms the phase purity of the LNMO NPs with a rhombohedral structure. FE-SEM and TEM analyses demonstrate the spherical morphology and uniform size distribution of the mesoporous particles having a size of ∼100 nm. LNMO NPs with a wide band gap Eg ∼ 3.56 eV (as evaluated by UV-vis analysis) were investigated for photocatalytic degradation of anionic methyl orange (MO) and cationic methylene blue (MB) dyes. An effective degradation of 84.57% for MO and 64.29% for MB was obtained in 60 min under UV irradiation. Radical trapping experiments performed with p-BQ, propanol, and ethanol as scavengers reveal the dominant role of superoxide (O2˙−) radicals in the degradation of MO and MB. The reaction mechanism for degradation was explained based on the band edge potentials of CB (−0.34 eV) and VB (3.22 eV), and radical formation. Higher efficiency for MO is ascribed to the effective electrostatic attraction between the negatively charged surface of the LNMO NPs and positively charged MO dye molecules as established by the point of zero charge (pHPZC = 8.43) of the LNMO NPs. The antimicrobial activity of LNMO NPs was also investigated against Gram-positive Bacillus subtilis, Gram-negative Escherichia coli bacteria, and Candida albicans (C. albicans), and Fusarium oxysporum as fungal pathogens. Maximum zone of inhibition (ZOI) of 31 mm and 32 mm was obtained for E. coli and B. subtilis, respectively, while 27 mm and 31 mm for Fusarium oxysporum and C. albicans, respectively. [ABSTRACT FROM AUTHOR]

The conversion of sound vibration into electrical potential is a critical function performed by cochlear hair cells. Unlike the regenerative capacity found in various other cells throughout the body, cochlear sensory cells lack the ability to regenerate once damaged. Furthermore, a decline in the quantity of these cells results in a deterioration of auditory function. Piezoelectric materials can generate electric charge in response to sound wave vibration, making them theoretically suitable for replacing hair cell function. This study explores an innovative approach using piezoelectric nanocomposite filaments, namely poly(vinylidene fluoride), poly(vinylidene fluoride)/barium titanate, and poly(vinylidene fluoride)/reduced graphene oxide, as self‐powered acoustic sensors designed to function in place of cochlear hair cells. These flexible filaments demonstrate a unique ability to generate electricity in response to frequency sounds from 50 up to 1000 Hz at moderate sound pressure levels (60–95 dB), approaching the audible range with an overall acoustoelectric energy conversion efficiency of 3.25%. Serving as self‐powered acoustic sensors, these flexible filaments hold promise for potential applications in cochlear implants, with a high sensitivity of 117.5 mV (Pa·cm2)−1. The cytocompatibility of these filaments was assessed through in vitro viability tests conducted on three cell lines, serving as a model for inner ear cells. [ABSTRACT FROM AUTHOR]

Each year in the United States (U.S.) thousands of older adults die from firearm-related injuries. The purpose of this study was to characterize the similarities and differences in the three main forms of firearm mortality (homicides, suicides, and unintentional) in older adults. Using the Web-based Inquiry Statistics Query and Reporting System (WISQARS) for the year 2021 we conducted a descriptive analysis (e.g. frequencies, percents, crude rates, rank orders) by gender, race/ethnicity, age, and census region of the U.S. Older adult firearm-related homicides were most likely to occur in males (61.2%), non-Hispanic whites (61.9%), ages 65-69 (42.4%) and in the South (53.6%). Firearm-related suicides were most common in males (91.4%), non-Hispanic whites (93.5%), ages 65-69 and 70-74 (24.8 and 24.7%, respectively), and in the South (45.1%). Firearm suicides were 12 times more common than firearm homicides and 99 times more common than unintentional firearm-related deaths. Both firearm homicides and suicides decreased with age. Years of potential life lost before 80 paralleled the demographic mortality data, resulting in over 45,000 potential years of life lost in 2021. These findings underscore the need to focus primary prevention of firearm-related mortality in older adults on the role of suicides, especially in non-Hispanic white males. In addition, improving mental health care access for older adults and their social connections are essential elements of preventing firearm-related suicides., Competing Interests: Declarations. Conflict of interest: The authors have no relevant financial or non-financial interests to disclose., (© 2025. The Author(s).)

Aggregation-Induced Emission (AIE) based nanomaterials are progressively gaining momentum owing to their evolvement into an interdisciplinary field ranging from biomass and biomolecule yield to image-guided photodynamic therapy. This study focuses on a novel strategy to enhance growth, lipid accumulation, and in vivo fluorescence visualisation in green microalgae Chlamydomonas reinhardtii using AIE nanoparticles to quantify radical changes. The absorption of AIE photosensitiser (PS), TTMN (C 26 H 17 N 3 S[M] + ) was recorded from 420 to 570 nm with a peak at 500 nm, and the emission ranged from 550 to 800 nm with a peak at 650 nm. As a reactive oxygen species (ROS) molecule, H 2 O 2 generation of TTMN in C. reinhardtii cells was detected with AIE nanoprobes TPE-BO (C 38 H 42 B 2 O 4 ). H 2 O 2 accumulation increased with the increase of TTMN concentrations. The maximum growth (2.1×10 7  cell/mL) was observed at 10 μM TTMN-exposed C. reinhardtii cells. Significant lipid accumulation was found in both 10 and 15 μM TTMN-treated cells. For lipid visualisation, an AIE nanoprobe, 2-DPAN (C 24 H 18 N 2 O) was used, and superior fluorescence was determined and compared with the traditional BODIPY dye. Cytotoxicity analysis of 10 μM TTMN on the HaCat cell line with 86.2 % cell viability revealed its high biocompatibility on living cells. This AIE-based nanotechnology provides a novel approach for microalgae-derived sustainable biomass and eco-friendly biofuel production., (© 2024 Wiley-VCH GmbH.)

Iron is an essential nutrient for the growth, survival and virulence of almost all bacteria. To access iron, many bacteria produce siderophores, molecules with a high affinity for iron. Research has highlighted substantial diversity in the chemical structure of siderophores produced by bacteria, as well as remarkable variety in the molecular mechanisms involved in strategies for acquiring iron through these molecules. The metal-chelating properties of siderophores, characterized by their high affinity for iron and ability to chelate numerous other metals (albeit with lower affinity compared with iron), have also generated interest in diverse fields. Siderophores find applications in the environment, such as in bioremediation and agriculture, in which emerging and innovative strategies are being developed to address pollution and enhance nutrient availability for plants. Moreover, in medicine, siderophores could be used as a tool for novel antimicrobial therapies and medical imaging, as well as in haemochromatosis, thalassemia or cancer treatments. This Review offers insights into the diversity of siderophores, highlighting their potential applications in environmental and medical contexts., Competing Interests: Competing interests: The author declares no competing interests., (© 2024. Springer Nature Limited.)