RESUMEN
Cellulose papers (CPs) possess a pore structure, rendering them ideal precursors for carbon scaffolds because of their renewability. However, achieving a tradeoff between high electromagnetic shielding effectiveness and low reflection coefficient poses a tremendous challenge for CP-based carbon scaffolds. To meet the challenge, leveraging the synergistic effect of gravity and evaporation dynamics, laminar CP-based carbon scaffolds with a bidirectional gradient distribution of Fe3O4 nanoparticles were fabricated via immersion, drying, and carbonization processes. The resulting carbon scaffold, owing to the bidirectional gradient structure of magnetic nanoparticles and unique laminar arrangement, exhibited excellent in-plane electrical conductivity (96.3 S/m), superior electromagnetic shielding efficiency (1805.9 dB/cm2 g), low reflection coefficients (0.23), and a high green index (gs, 3.38), suggesting its green shielding capabilities. Furthermore, the laminar structure conferred upon the resultant carbon scaffold a surprisingly anisotropic thermal conductivity, with an in-plane thermal conductivity of 1.73 W/m K compared to a through-plane value of only 0.07 W/m K, confirming the integration of thermal insulation and thermal management functionalities. These green electromagnetic interference shielding materials, coupled with thermal insulation and thermal management properties, hold promising prospects for applications in sensitive devices.
Asunto(s)
Carbono , Celulosa , Carbono/química , Celulosa/química , Conductividad Térmica , Conductividad Eléctrica , TemperaturaRESUMEN
Food safety is related to human health and sustainable development. International food trade poses food safety risks through the collateral transport of toxic chemicals that are detrimental to human health. Domestic interprovincial trade has similar effects within countries but has not been comprehensively investigated previously. Here, we assessed the effects of interprovincial trade on food safety and human dietary exposure to short-chain chlorinated paraffins (SCCPs), a group of emerging persistent toxic chemicals, in seafood across China by synthesizing data from field observation and various models. Our findings indicate that there is a higher level of SCCPs exposure risk in coastal provinces compared to inland provinces. Approximately, 70.3% of human exposure to SCCPs through seafood consumption in China was embodied in the interprovincial seafood trade in 2021. Specifically, the domestic trade led to a remarkable increase in SCCPs exposure in the coastal provinces in South China, attributable to low SCCPs pollution in these provinces and imported seafood from those provinces with high SCCPs pollution. In contrast, human exposure to SCCPs decreased in those coastal provinces in East China due to importing seafood from those provinces with low SCCPs concentrations. The interprovincial seafood trade routes were optimized by linear programming to minimize human exposure to SCCPs considering both shipping cost and health risk constraints. The optimized trade routes reduced the national per capita SCCPs exposure through seafood consumption by over 12%. This study highlights the importance of interprovincial food trade in the risk assessment of toxic chemicals.
RESUMEN
Gambogic acid is a natural compound with anticancer properties and is effective for many tumors. But its low water solubility and dose-dependent side effects limit its clinical application. This study aims to develop a novel drug delivery system for intratumoral delivery of gambogic acid. In our experimental study, we propose a new method for encapsulating gambogic acid nanoparticles using a manganese composite hyaluronic acid hydrogel as a carrier, designed for targeted drug delivery to tumors. The hydrogel delivery system is synthesized through the coordination of hyaluronic acid-dopamine (HA-DOPA) and manganese ions. The incorporation of manganese ions serves three purposes:1.To form cross-linked hydrogels, thereby improving the mechanical properties of HA-DOPA.2.To monitor the retention of hydrogels in vivo in real-time using magnetic resonance imaging (MRI).3.To activate the body's immune response. The experimental results show that the designed hydrogel has good biosafety, in vivo sustained release effect and imaging tracking ability. In the mouse CT26 model, the hydrogel drug-loaded group can better inhibit tumor growth. Further immunological analysis shows that the drug-loaded hydrogel group can stimulate the body's immune response, thereby better achieving anti-tumor effects. These findings indicate the potential of the developed manganese composite hyaluronic acid hydrogel as an effective and safe platform for intratumoral drug delivery. The amalgamation of biocompatibility, controlled drug release, and imaging prowess positions this system as a promising candidate for tumor treatment.