Mesoporous TiO(2) spheres with a large surface area and rich surface hydroxyl groups have been prepared through a light-driven synthetic strategy, and the as-prepared mesoporous material is able to convert urea to carbon nitride efficiently under a mild condition.

A light-inducing approach has been demonstrated for the preparation of porous TiO(2) with a large number of stored electrons, which can provide an electron source for subsequent use in redox reactions and provide a spin source to achieve a new room-temperature ferromagnetic semiconductor.

Nanoparticles have been widely tested as drug delivery carriers or imaging agents, largely because of their ability to selectively accumulate in tumors through the enhanced permeability and retention (EPR) effect. However, studies show that many tumors afford a less efficient EPR effect and that many nanoparticles are trapped in the perivascular region after extravasation and barely migrate into tumor centers. This is to a large degree attributed to the dense tumor extracellular matrix (ECM), which functions as a physical barrier to prevent efficient nanoparticle extravasation and diffusion. In this study, we report a photodynamic therapy (PDT) approach to enhance tumor uptake of nanoparticles. Briefly, we encapsulate ZnFPc, a photosensitizer, into ferritin nanocages, and then conjugate to the surface of the ferritin a single chain viable fragment (scFv) sequence specific to fibroblast activation protein (FAP). FAP is a plasma surface protein widely upregulated in cancer-associated fibroblasts (CAFs), which is a major source of the ECM fiber components. We found that the scFv-conjugated and ZnFPc-loaded ferritin nanoparticles (scFv-Z@FRT) can mediate efficient and selective PDT, leading to eradication of CAFs in tumors. When tested in bilateral 4T1 tumor models, we found that the tumor accumulation of serum albumin (BSA), 10 nm quantum dots (QDs), and 50 nm QDs was increased by 2-, 3.5-, and 18-fold after scFv-Z@FRT mediated PDT. Our studies suggest a novel and safe method to enhance the delivery of nanoparticles to tumors.

Achieving efficient and direct conversion of methane under mild conditions is of great significance for innovations in the chemical industry. However, the efficiency and lifetime of most catalysts remain too far from practical requirements, since it is difficult to break the first C−H bond of methane as well as to suppress the following complete dehydrogenation (or overoxidation) and the resulting carbonaceous deposition (or CO2). Here, we report that wurtzite GaN:ZnO solid solutions exhibit unique and unprecedented photocatalytic performances for the nonoxidative coupling of methane at room temperature, exclusively generating ethane with nearly stoichiometric H2. High conversion rate (>330 μmol g−1 h−1), long‐term stability (>70 h), and superior coke‐resistance were achieved. At 293 K, the methane conversion exceeds 7 %, comparable to the equilibrium conversion of thermal catalysis at 910 K. Mechanistic studies revealed that the N‐ZnGa‐ON units and the absence of acid sites on the surface played crucial roles in reactivity and coke resistance, respectively.

Antarctica preserves Earth's largest ice sheet which, in response to climate warming, may lose ice mass and raise sea level by several metres. The ice-sheet bed exerts critical controls on dynamic mass loss through feedbacks between water and heat uxes, topographic forcing and basal sliding. Here we show that through hydrogeological processes, sedimentary basins amplify critical feedbacks that are known to impact ice-sheet retreat dynamics. We create a high-resolution subglacial bedrock classi cation for Antarctica by applying a supervised machine learning method to geophysical data, revealing the distribution of sedimentary basins. Sedimentary basins are found in the upper reaches of Antarctica's most rapidly changing ice streams, including Thwaites and Pine Island Glaciers. Hydro-mechanical numerical modelling reveals that where sedimentary basins exist, water discharge rate scales with the rate of ice unloading and the resulting hydrological instabilities are likely to amplify further retreat and unloading. These results indicate that the presence of a sedimentary bed in the catchment focuses instabilities that increase the vulnerability of the ice streams to rapid retreat and enhanced dynamic mass loss. MainPaleoclimate data indicate that change of the Antarctic ice-sheet is tightly coupled with climate forcing 1 .Under a warming future climate, Antarctic ice-sheet mass loss may cause a multi-meter contribution to sea level change on centennial timescales 2 . Although the current and near future Antarctic contribution to sea level rise is subordinate to other sources, satellite observations are consistent with accelerating mass loss over the last two decades 3 . Recent observations suggest that substantial and accelerating ice mass loss has occurred in several ice stream catchments in both West and East Antarctica 3 . However, in predictions of future sea level change, the effects of dynamic ice mass loss in Antarctica remain highly uncertain 4 . This uncertainty re ects in particular the identi cation of critical thresholds for dynamic mass loss, which are often associated with changing basal conditions. Subglacial sedimentary basins are thick sediment accumulations and consolidated sedimentary rocks deposited and preserved beneath the ice-sheet. They are associated with different basal boundary conditions than a crystalline bedrock, because of their larger primary porosity, intrinsic permeability, lower relief surfaces, rheological strati cation, and reduced mechanical strength. During glacial loading and unloading cycles, subglacial sedimentary basins may promote groundwater exchange ux 5-7 associated with advected heat ux 5,6 . Sedimentary basins may also provide a more readily eroded source of subglacial till 8 .

Photodynamic therapy (PDT) is a novel treatment modality that is under intensive preclinical investigations for a variety of diseases, including cancer. Despite extensive studies in this area, selective and effective photodynamic agents that can specifically accumulate in tumors to reach a therapeutic concentration are limited. Although recent attempts have produced photosensitizers (PSs) complexed with various nanomaterials, the tedious preparation steps and poor tumor efficiency of therapy hamper their utilization. Here, we developed a CD44-targeted nanophotodynamic agent by physically encapsulating a photosensitizer, Ce6, into a hyaluronic acid nanoparticle (HANP), which was hereby denoted HANP/Ce6. Its physical features and capability for photodynamic therapy were characterized in vitro and in vivo. Systemic delivery of HANP/Ce6 resulted in its accumulation in a human colon cancer xenograft model. The tumor/muscle ratio reached 3.47 ± 0.46 at 4 h post injection, as confirmed by fluorescence imaging. Tumor growth after HANP/Ce6 treatment with laser irradiation (0.15 W/cm, 630 nm) was significantly inhibited by 9.61 ± 1.09-fold compared to that in tumor control groups, which showed no change in tumor growth. No apparent systemic and local toxic effects on the mice were observed. HANP/Ce6-mediated tumor growth inhibition was accessed and observed for the first time by F-fluoro-2-deoxy-d-glucose positron emission tomography as early as 1 day after treatment and persisted for 14 days within our treatment time window. In sum, our results highlight the imaging properties and therapeutic effects of the novel HANP/Ce6 theranostic nanoparticle for CD44-targeted PDT cancer therapy that may be potentially utilized in the clinic. This HANP system may also be applied for the delivery of other hydrophobic PSs, particularly those that could not be chemically modified.

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Magnetic n-type semiconductor Fe3O4 nanoparticle and p-type semiconductor FeWO4 nanowire heterostructures were successfully synthesized without any surfactants or templates via a facile one-step hydrothermal process at 160 °C. The heterojunction structure and morphology were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Magnetic measurements indicated the coexistence of ferrimagnetic behavior of Fe3O4 and weak antiferromagnetic behavior of FeWO4. The degradation of methylene blue (MB) under UV-Visible light irradiation was studied as a model experiment to evaluate the catalytic activity of the Fe3O4/FeWO4 heterostructure p-n junctions. The decomposition efficiency was 97.1% after one hour UV-Visible irradiation. This magnetic photocatalyst can be easily recovered from the solution using a permanent magnet and redispersed by removing the magnet.