Quantitative identification on spatial mismatch characteristics between supply and demand of carbon sequestration services.

Exploring the mismatch between supply and demand (SD) for carbon sequestration services (CSS) is essential for achieving the "double carbon" goal. However, more studies are needed on the traits of the spatial mismatch between SD in mountainous cities. We used the CASA model and the IPCC emission factor approach to address this issue and quantify the SD of CSS in Chongqing. Second, we established a matching relationship model for the SD of CSS in Chongqing. Finally, we applied the Structural Equation Model with the Partial Dependence Plots model to reveal the influencing factors and internal mechanisms of spatial mismatch between the SD of CSS in Chongqing. The outcomes confirmed a decrease in fashion in the total supply of CSS in Chongqing and growth in fashion in general demand from 2000 to 2020. The SD mismatch was mainly concentrated inside the central city and other built-up areas. The SD mismatch area had increased by 390%, indicating a continuous upward trend. In exploring the factors influencing the mismatch between the SD of CSS in Chongqing, supply is mainly positively influenced by NDVI, and demand and supply-demand relationships are influenced by population density and LUCC. We proposed policy suggestions to alleviate the spatial mismatch and practical significance for achieving the "double carbon" goal and promoting sustainable development.

Mechanism of the two-dimensional WSeTe/Zr2CO2 direct Z-scheme van der Waals heterojunction as a photocatalyst for water splitting.

The direct Z-scheme van der Waals (vdW) heterojunctions based on biomimetic artificial photosynthesis are a promising strategy for enhancing photocatalytic activity. Therefore, the search for superior direct Z-scheme photocatalysts is an urgent task. Herein, we predicted the WSeTe/Zr2CO2 heterostructure as a potential direct Z-scheme photocatalyst based on density functional theory (DFT). The bands of the WSeTe/Zr2CO2 heterojunction follow a typical Type-II arrangement, where the interlayer band gap is smaller than that of the individual molecular layers, and staggered alignment of the large band-edge creates conditions that allow for a direct Z-scheme. The position of the Fermi energy levels of the two monolayers determines the formation of the built-in electric field pointing from WSeTe to Zr2CO2, promoting the desired interlayer electron-hole (e--h+) recombination and suppressing the undesired carrier recombination. Finally, in-plane biaxial strain can effectively modulate the optoelectronic properties of the catalyst, while compressive strain has a more pronounced effect on the overpotential driving force of the material. Therefore, the WSeTe/Zr2CO2 heterojunction is an effective new photocatalyst satisfying the direct Z-scheme charge transfer mechanism with its specific application.

Immobilized thrombin on X-ray radiopaque polyvinyl alcohol/chitosan embolic microspheres for precise localization and topical blood coagulation.

Trans-catheter arterial embolization (TAE) plays an important role in treating various diseases. The available embolic agents lack X-ray visibility and do not prevent the reflux phenomenon, thus hindering their application for TAE therapy. Herein, we aim to develop a multifunctional embolic agent that combines the X-ray radiopacity with local procoagulant activity. The barium sulfate nanoparticles (BaSO4 NPs) were synthesized and loaded into the polyvinyl alcohol/chitosan (PVA/CS) to prepare the radiopaque BaSO4/PVA/CS microspheres (MS). Thereafter, thrombin was immobilized onto the BaSO4/PVA/CS MS to obtain the thrombin@BaSO4/PVA/CS MS. The prepared BaSO4/PVA/CS MS were highly spherical with diameters ranging from 100 to 300 µm. In vitro CT imaging showed increased X-ray visibility of BaSO4/PVA/CS MS with the increased content of BaSO4 NPs in the PVA/CS MS. The biocompatibility assessments demonstrated that the MS were non-cytotoxic and possessed permissible hemolysis rate. The biofunctionalized thrombin@BaSO4/PVA/CS MS showed improved hemostatic capacity and facilitated hemostasis in vitro. Additionally, in vivo study performed on a rabbit ear embolization model confirmed the excellent X-ray radiopaque stability of the BaSO4/PVA/CS MS. Moreover, both the BaSO4/PVA/CS and thrombin@BaSO4/PVA/CS MS achieved superior embolization effects with progressive ischemic necrosis on the ear tissue and induced prominent ultrastructural changes in the endothelial cells. The findings of this study suggest that the developed MS could act as a radiopaque and hemostatic embolic agent to improve the embolization efficiency.

Water-stable and finasteride-loaded polyvinyl alcohol nanofibrous particles with sustained drug release for improved prostatic artery embolization - In vitro and in vivo evaluation.

Prostatic artery embolization (PAE) has been a well-established treatment for benign prostatic hyperplasia (BPH). To enhance the therapeutic efficacy, a strategy is to use embolic agent preloaded with 5α-reductase inhibitors for localized drug delivery. In this study, finasteride (FNS) was encapsulated into the polyvinyl alcohol (PVA) nanofibers via co-electrospinning technique, followed by heat treatment and cryogenic grinding to convert them into nanofibrous particles as a drug-loaded embolic agent. The FNS was found to be distributed uniformly in PVA nanofibers, and the processed FNS/PVA nanofibrous particles were 272 µm in mean particle size. Besides, the studies on the composition, thermal properties, swelling ratio, and water stability of the nanofibers and drug showed that the FNS remained its crystalline state in PVA nanofibers. The heat treatment increased the crystallinity of nanofibers and rendered them water stability. Both FNS and PVA possessed excellent thermal stability at high temperature (150 °C). In addition, in vitro drug release studies suggested the FNS followed a favorable sustained release up to 744 h. Furthermore, the cell viability and hemocompatibility assays indicated the nanofibers possessed excellent cytocompatibility and with no evidence of hemolysis. More importantly, the in vivo PAE procedures on beagles demonstrated the crosslinked FNS/PVA nanofibrous particles exhibited higher embolization efficacy with more obvious prostate volume (PV) reduction compared to crosslinked PVA nanofibrous particles after embolization for 1, 3, and 6 months (P < 0.05). Therefore, such drug-loaded PVA nanofibrous particles combined physical embolization and localized medical therapy together, which offer great potential to be used as an effective embolic agent for BPH therapy.

Development of finasteride/PHBV@polyvinyl alcohol/chitosan reservoir-type microspheres as a potential embolic agent: from in vitro evaluation to animal study.

Benign prostatic hyperplasia (BPH) is a prevalent urological disease affecting elders. Currently, the prostatic artery embolization (PAE) is considered as a minimally invasive and safe technique to treat BPH. However, various drug-loaded embolic agents have not been thoroughly investigated in BPH therapy. In this study, finasteride/poly(3-hydroxybutyrate-3-hydroxyvalerate)@polyvinyl alcohol/chitosan (FNS/PHBV@PVA/CS) reservoir-type microspheres were prepared via the solid-in-water-in-oil (S/W/O) emulsion crosslinking method with the aim to reduce the burst effect and control localized drug delivery. The structure and properties of the drug and resultant microspheres were characterized via field emission scanning electron microscopy (FESEM), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The results showed that the drug-loaded hybrid microspheres were well-dispersed and spherical with a mean diameter of 238.1 ± 27.3 µm. All samples exhibited excellent thermal stability. The FNS/PHBV microspheres were successfully encapsulated inside the PVA/CS polymeric matrix, which effectively suppressed the burst effect and prolonged the drug release up to 51 days. In vitro biocompatibility assessment indicated that the microspheres possessed excellent cytocompatibility and hemocompatibility. Furthermore, in vivo studies performed in the rabbit ear embolization model showed the formation of progressive ischemic necrosis after treatment for various periods. Histopathological studies revealed that the microspheres completely occluded the blood vessels with minimal foreign body response and formed the fibrotic area at the periphery of embolized arteries. Furthermore, the auricular vascular endothelial cells showed acute ultrastructural changes, associated with the ischemic necrosis induced by the embolization procedures. All these findings suggest that the FNS/PHBV@PVA/CS hybrid microspheres could be used as a promising drug delivery system for potential applications in BPH therapy.