Photosynthetic Tumor Oxygenation by Photosensitizer-Containing Cyanobacteria for Enhanced Photodynamic Therapy

Sustained tumor oxygenation is of critical importance during type-II photodynamic therapy (PDT), which depends on the intratumoral oxygen level for the generation of reactive oxygen species. Herein, the modification of photosynthetic cyanobacteria with the photosensitizer chlorin e6 (ce6) to form ce6-integrated photosensitive cells, termed ceCyan, is reported. Upon 660 nm laser irradiation, sustained photosynthetic O₂ evolution by the cyanobacteria and the immediate generation of reactive singlet oxygen species (¹O₂) by the integrated photosensitizer could be almost simultaneously achieved for tumor therapy using type-II PDT both in vitro and in vivo. This work contributes a conceptual while practical paradigm for biocompatible and effective PDT using hybrid microorganisms, displaying a bright future in clinical PDT by microbiotic nanomedicine.     

Triruthenium carbonyl complexes containing bidentate pyridine–alkoxide ligands for highly efficient oxidation of primary and secondary alcohols

Reactions of substituted pyridylalkanol 6-CH₃PyCH₂CH(OH)R (R = Ph (L¹H), R = 4-CH₃C₆H₄ (L²H), R = 4-OCH₃C₆H₄ (L³H), R = 4-ClC₆H₄ (L⁴H), R = 4-BrC₆H₄ (L⁵H), R = 4-CF₃C₆H₄ (L⁶H)) with Ru₃(CO)₁₂ in refluxing tetrahydrofuran afforded the corresponding ruthenium carbonyl complexes [6-CH₃PyCH₂CHRO]₂Ru₃(CO)₈ (R = Ph ( 1a ), R = 4-CH₃C₆H₄ ( 1b ), R = 4-OCH₃C₆H₄ ( 1c ), R = 4-ClC₆H₄ ( 1d ), R = 4-BrC₆H₄ ( 1e ), R = 4-CF₃C₆H₄ ( 1f )) in good yields. These ruthenium complexes were well characterized using elemental analysis and Fourier transform infrared and NMR spectroscopies. Furthermore, their crystal structures were determined using single-crystal X-ray diffraction analysis. Complexes 1a – 1f were found to be highly active toward oxidation of a wide range of primary and secondary alcohols to corresponding aldehydes and ketones within 5 minutes in the presence of N-methylmorpholine-N-oxide as oxidant.     

A High Faraday Efficiency NiMoO4 Nanosheet Array Catalyst by Adjusting the Hydrophilicity for Overall Water Splitting

To obtain a highly active, stable, and binder-free electrode based on transition-metal compounds for water splitting, nickel foam-supported 3D NiMoO₄ nanosheet arrays modified with 0D Fe-doped carbon quantum dots (Fe-CQDs/NiMoO₄/NF) are synthesized. The structure characterizations indicated that 0D Fe-CQDs are evenly dispersed onto the NiMoO₄ sheets of the arrays. The contact angle analysis confirmed that the surface hydrophilia of the arrays is improved after the 0D Fe-CQDs are deposited 3D on the NiMoO₄ sheets. Here, both the activity and durability in electrochemical water splitting are significantly enhanced with the Fe-CQDs/NiMoO₄/NF catalysts. At a current density of 10 mA cm⁻², the resultant Fe-CQDs/NiMoO₄/NF revealed an overpotential of only 117 mV for the hydrogen evolution reaction (HER), a relatively low overpotential of 336 mV toward the oxygen evolution reaction (OER), and a Faraday efficiency of up to 99 %. This performance can be attributed to the unique 3D nanosheet array structure, the synergistic effect, and the optimal hydrophilia for gas evolution evolved from the electrode surface.     

Degradation of pyrazinamide in aqueous solution by electron beam irradiation: kinetics,influence factors and mechanism study

The degradation of pyrazinamide (PZA) by electron beam irradiation (EBI) was studied. It was found that the degradation of PZA was efficient with the removal rate of 99% for 0.2 mM PZA under 5 kGy, and the degradation kinetics followed pseudo-first-order kinetics. The presence of CO₃^2?, HCO₃^?, NO₃^?, and fulvic acid inhibited the degradation of PZA. The addition of H₂O₂ or K₂S₂O₈ effectively enhanced the degradation and mineralization of PZA. The scavenger experiments and quantum chemical calculations showed that ^·OH was the primary reactive species in the degradation. The identification of intermediates and quantum chemical calculations illustrated the mechanism of degradation.

     

2D Metal–Organic Framework Derived CuCo Alloy Nanoparticles Encapsulated by Nitrogen-Doped Carbonaceous Nanoleaves for Efficient Bifunctional Oxygen Electrocatalyst and Zinc–Air Batteries

The development of efficient bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) still remains a challenge in a wide range of renewable energy technologies. Herein, CuCo alloy nanoparticles encapsulated by nitrogen-doped carbonaceous nanoleaves (CuCo-NC) have been synthesized from a Cu(OH)₂/2D leaf-like zeolitic imidazolate framework (ZIF-L)-pyrolysis approach. Leaf-like Cu(OH)₂ is first prepared by the ultrasound-induced self-assembly of Cu(OH)₂ nanowires. The efficient encapsulation of Cu(OH)₂ in ZIF-L is obtained owing to the morphology fitting between the leaf-like Cu(OH)₂ and ZIF-L. CuCo-NC catalysts present superior electrocatalytic activity and stability toward ORR and OER over the commercial Pt/C and IrO₂, respectively, which are further used as bifunctional oxygen electrocatalysts in Zn–air batteries and exhibit impressive performance, with a high peak power density of 303.7 mW cm⁻², large specific capacity of up to 751.4 mAh g⁻¹ at 20 mA cm⁻², and a superior recharge stability.     

Rough Marcinkiewicz integrals with mixed homogeneity on product spaces

In this paper, the parabolic Marcinkiewicz integral operators on the product spaces Rm × Rn (m, n≥ 2) are studied. The Lp -boundedness for such operators are established under rather weak size conditions of the kernels, which essentially improve or extend certain previous results.     

Microwave-assisted architectural control fabrication of 3D CdS structures

A facile microwave-assisted solvothermal method was developed for the controlled synthesis of novel 3D CdS structures. Dendrite-, star-, popcorn- and hollow sphere-like CdS structures could be obtained by changing the reaction conditions including the reaction temperature and the amounts of reagents and solvents. The products were examined by using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman and photoluminescence spectroscopy. Results revealed that the final structures were related to the solvent properties such as surface tension and viscosity. The degree of supersaturation is also responsible for the morphology variation and it can be adjusted by the reaction temperature. The CdS products with different morphologies exhibited interesting shape-dependent optical properties and photocatalytic activities.     

Platinum(II) complexes bearing bulky Schiff base ligands anchored onto mesoporous SBA‐15 supports as efficient catalysts for hydrosilylation

Reported herein is an easy‐to‐prepare novel heterogeneous catalyst of platinum complexes bearing binary ligands of bidentate naphthalenolimine and cyclo‐1,5‐octadiene that are anchored onto mesoporous silica SBA‐15. The presence of the binary ligands not only stabilized the platinum, but also enabled the platinum atoms to form nanoclusters with diameters of ca 1 nm, and led to high platinum loading (8.69 wt%). Moreover, the platinum catalyst exhibited high catalytic activity towards hydrosilylation of terminal alkenes and styrene with silanes under mild and solvent‐free conditions, with excellent regioselectivity.     

First Passage Risk Probability Minimization for Piecewise Deterministic Markov Decision Processes

Acta Mathematicae Applicatae Sinica, English Series - This paper is an attempt to study the minimization problem of the risk probability of piecewise deterministic Markov decision processes...