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Although two-dimensional (2D) layered double hydroxides (LDHs) have been widely used as efficient nanoagents for biological diagnosis and treatment, they have been found to be inert as photosensitizers (PSs) for photodynamic therapy (PDT). Herein, we report the defect engineering of ultrathin 2D CoMo-LDH and NiMo-LDH nanosheets as highly active inorganic PSs for PDT in the third near-infrared (NIR-III) window. Hydrothermal-synthesized 2D CoMo-LDH and NiMo-LDH nanosheets are etched via a simple acid treatment to obtain defect-rich CoMo-LDH and NiMo-LDH nanosheets. Importantly, the defect-rich CoMo-LDH nanosheets exhibit much higher activity (~97 times) for generation of reactive oxygen species than that of the pristine CoMo-LDH nanosheets under a NIR-III 1567 nm laser irradiation. Therefore, after modification with polyethylene glycol, the defect-rich CoMo-LDH nanosheets can be used as an efficient inorganic PS for PDT to efficiently induce cancer cells apoptosis in vitro and eradicate tumors in vivo under 1567 nm laser irradiation.

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-The amount and pattern of litterfall, its nutrient return, initial chemistry of leaf litter, and dynamics of N, P and K associated with leaf-litter decomposition were studied in 33-year-old plantations of two coniferous trees, Chinese fir (Cunninghamia lanceolata, CF) and Fokienia hodginsii (FH), and two broadleaved trees, Ormosia xylocarpa (OX) and Castanopsis kawakamii (CK), and compared with that of an adjacent natural forest of Castanopsis kawakamii (NF, ~150 year old) in Sanming, Fujian, China. Mean annual total litterfall over 3 years of observations was 5.47 Mg·ha -1 in the CF, 7.29 Mg·ha -1 in the FH, 5.69 Mg·ha -1 in the OX, 9.54 Mg·ha -1 in the CK and 11.01 Mg·ha -1 in the NF respectively; of this litterfall, leaf contribution ranged from 58% to 72%. Litterfall in the OX, CK, and NF showed an unimodal distribution pattern, while for the CF and FH, the litterfall pattern was multi-peak. The highest annual Ca and Mg returns were noticed in the FH and in the CK, respectively. The amounts of N, P, and K which potentially returned to the soil were the highest in the NF. The loss of dry matter in leaf litter exhibited a negative exponential pattern during the 750-day decomposition. Using the model x t = A + Be -kt , the annual dry matter decay constants (k) ranged from 1.157 in CF to 4.619 in OX. Initial lignin concentration and lignin/N ratios showed significantly negative correlations with k (r = -0.916, P = 0.011; r = -0.473, P = 0.041), whereas initial N concentration showed low positive correlations (r = 0.225, P = 0.038). Using the model x t = A + Be -kt , the decay constant of N (k N ) ranged from 0.769 in CF to 4.978 in OX; the decay constant of P (k P ) ranged from 1.967 in the OX to 4.664 in the NF; and the decay constant of K (k K ) seemed very similar among these forests (5.250-5.992). The decay constants of nutrients during leaf-litter decomposition can be arranged in the sequence of k K > k P > k N , except for leaf litter of OX wherelitterfall / nutrient return / litter decomposition / reafforestation / natural forest / Cunninghamia lanceolata / Fokienia hodginsii / Ormosia xylocarpa / Castanopsis kawakamii Résumé -Chute de feuilles, retour de nutriments et décomposition des feuilles de la litière dans quatre plantations en comparaison avec une forêt naturelle en Chine subtropicale. La quantité et la dynamique de chute de litière, le retour des nutriments, la composition chimique initiale des feuilles de la litière et la dynamique de N, Pet K associée à la décomposition de la litière ont été étudiés dans 2 plantations de conifères (Cunninghamia lanceolata, CF and Fokienia hodginsii, FH) âgées de 33 ans et 2 peuplements feuillus (Ormosia xylocarpa, OX et Castanopsis kawakamii, CK), comparativement à une forêt naturelle adjacente de Castanopsis kawakamii, NF, âgée d'environ 150 ans à Sanming, Fujian, Chine. Sur 3 années d'observations, la moyenne annuelle de chute de litière a été de 5,47 Mg·ha -1 pour CF, 7,29 Mg·ha -1 pour FH, 5,69 Mg·h -1 pour OX, 9,54 Mg·hg -1 pour CK et 11,01 Mg·h...

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Photodynamic therapy (PDT) has become a promising cancer treatment approach with superior advantages. However, it remains a grand challenge to develop tumor microenvironment (TME)‐responsive photosensitizers (PSs) for tumor‐targeting precise PDT. Herein, the coupling Lactobacillus acidophilus (LA) probiotics with 2D CoCuMo layered‐double‐hydroxide (LDH) nanosheets (LA&LDH) is reported as a TME‐responsive platform for precise NIR‐II PDT. The CoCuMo‐LDH nanosheets loaded on LA can be transformed from crystalline into amorphous through etching by the LA‐metabolite‐enabled low pH and overexpressed glutathione. The TME‐induced in situ amorphization of CoCuMo‐LDH nanosheets can boost its photodynamic activity for singlet oxygen (1O2) generation under 1270 nm laser irradiation with relative 1O2 quantum yield of 1.06, which is the highest among previously reported NIR‐excited PSs. In vitro and in vivo assays prove that the LA&LDH can effectively achieve complete cell apoptosis and tumor eradication under 1270 nm laser irradiation. This study proves that the probiotics can be used as a tumor‐targeting platform for highly efficient precise NIR‐II PDT.

We report a bistable resistance switching effect in amorphous InGaZnO (a-IGZO) thin films deposited by a pulsed laser deposition method. The electrical properties of a-IGZO thin films were controlled by the oxygen partial pressure during deposition and this determined the resistance switching effect. We also observed the resistance switching effect with various electrodes such as Pt, Au, and Al. We suggest that the resistance switching effect is related to the formation of a conducting path by metal and/or oxygen vacancy defects in the a-IGZO matrix.

Although artificial bone repair scaffolds, such as titanium alloy, bioactive glass, and hydroxyapatite (HAp), have been widely used for treatment of large-size bone defects or serious bone destruction, they normally exhibit unsatisfied bone repair efficiency because of their weak osteogenic and angiogenesis performance as well as poor cell crawling and adhesion properties. Herein, the surface functionalization of MgAlEu-layered double hydroxide (MAE-LDH) nanosheets on porous HAp scaffolds is reported as a simple and effective strategy to prepare HAp/MAE-LDH scaffolds for enhanced bone regeneration. The surface functionalization of MAE-LDHs on the porous HAp scaffold can significantly improve its surface roughness, specific surface, and hydrophilicity, thus effectively boosting the cells adhesion and osteogenic differentiation. Importantly, the MAE-LDHs grown on HAp scaffolds enable the sustained release of Mg 2+ and Eu 3+ ions for efficient bone repair and vascular regeneration. In vitro experiments suggest that the HAp/MAE-LDH scaffold presents much enhanced osteogenesis and angiogenesis properties in comparison with the pristine HAp scaffold. In vivo assays further reveal that the new bone mass and mineral density of HAp/MAE-LDH scaffold increased by 3.18-and 2.21-fold, respectively, than that of pristine HAp scaffold. The transcriptome sequencing analysis reveals that the HAp/MAE-LDH scaffold can activate the Wnt/𝜷-catenin signaling pathway to promote the osteogenic and angiogenic abilities.