The reinforcing effects of highly effective flame retardant magnesium hydroxide (FMX) content on the tensile and flexural properties of filled polypropylene (PP) composites were investigated within ...the FMX weight fraction range from 5 to 60 wt%. It was found that the Young's modulus and flexural modulus increased approximately linearly while the tensile yield strength and tensile fracture strength decreased slightly with increasing the FMX weight fraction. When the FMX weight fraction was lower than 20%, the tensile elongation at break decreased considerably, and then decreased slightly; the flexural strength increased when the FMX weight fraction was lower than 30%, and then decreased slightly. The tensile properties increased with increasing rate of tension. Moreover, the tensile yield strength of the composites was estimated using an equation proposed in previous work, and good agreement was shown between the predicted and the measured data.
Elucidation of relationship among chemical structure, cellular uptake, localization, and biological activity of anticancer metal complexes is important for the understanding of their mechanisms of ...action. Organometallic rhenium(I) tricarbonyl compounds have emerged as potential multifunctional anticancer drug candidates that can integrate therapeutic and imaging capabilities in a single molecule. Herein, two mononuclear phosphorescent rhenium(I) complexes (Re1 and Re2), along with their corresponding dinuclear complexes (Re3 and Re4), were designed and synthesized as potent anticancer agents. The subcellular accumulation of Re1–Re4 was conveniently analyzed by confocal microscopy in situ in live cells by utilizing their intrinsic phosphorescence. We found that increased lipophilicity of the bidentate ligands could enhance their cellular uptake, leading to improved anticancer efficacy. The dinuclear complexes were more potent than the mononuclear counterparts. The molecular anticancer mechanisms of action evoked by Re3 and Re4 were explored in detail. Re3 with a lower lipophilicity localizes to lysosomes and induces caspase‐independent apoptosis, whereas Re4 with higher lipophilicity specially accumulates in mitochondria and induces caspase‐independent paraptosis in cancer cells. Our study demonstrates that subcellular localization is crucial for the anticancer mechanisms of these phosphorescent rhenium(I) complexes.
Directing by design: The anticancer mechanisms of phosphorescent rhenium(I) tricarbonyl polypyridine complexes are found to be closely associated with their organelle‐specific localizations (see figure).
Understanding the reinforcing mechanisms should be meaningful for preparation of new polymer composites. The reinforcing mechanisms of the inorganic particulate-filled polymer composites were ...analyzed and discussed in the present paper, and concluded several reinforcing theories on the basis of the previous studies, such as interfacial adhesion reinforcing theory, filler inducing crystallization reinforcing theory, filler frame reinforcing theory, and synergistic reinforcing effect theory. The reinforcing effects should be related closely to the filler shape and size, in addition to the filler concentration and dispersion in the matrix. Consequently, to describe accurately the reinforcing mechanisms of the composites, two or more reinforcing theories should be used for the actual composite system, and one of among them should be usually as the major reinforcing mechanism. Finally, the quantitative characterization of the reinforcement was described.
Stimuli-activatable photosensitizers (PSs) are highly desirable for photodynamic therapy (PDT) to selectively demolish tumor cells. On the other hand, lysosomes are emerging as attractive anticancer ...targets. Herein, four cyclometalated iridium(iii)-β-carboline complexes with pH-responsive singlet oxygen (
O
) production and lysosome-specific imaging properties have been designed and synthesized. Upon visible light (425 nm) irradiation, they show highly selective phototoxicities against cancer cells. Notably, complex
(Ir(N^C)
(N^N)(PF
) in which N^C = 2-phenylpyridine and N^N = 1-(2-benzimidazolyl)-β-carboline) displays a remarkably high phototoxicity index (PI = IC
in the dark/IC
in light) of >833 against human lung carcinoma A549 cells. Further studies show that
-mediated PDT induces caspase-dependent apoptosis through lysosomal damage. The pH-responsive phosphorescence of complex
can be utilized to monitor the lysosomal integrity upon PDT, which provides a reliable and convenient method for
monitoring of therapeutic effect and real-time assessment of treatment outcome. Our work provides a strategy for the construction of highly effective multifunctional subcellular targeted photodynamic anticancer agents through rational structural modification of phosphorescent metal complexes.
Precise quantitative measurement of viscosity at the subcellular level presents great challenges. Two-photon phosphorescence lifetime imaging microscopy (TPPLIM) can reflect micro-environmental ...changes of a chromophore in a quantitative manner. Phosphorescent iridium complexes are potential TPPLIM probes due to their rich photophysical properties including environment-sensitive long-lifetime emission and high two-photon absorption (TPA) properties. In this work, a series of iridium(iii) complexes containing rotatable groups are developed as mitochondria-targeting anticancer agents and quantitative viscosity probes. Among them,
(Ir(ppy-CHO)
(dppe)PF
; ppy-CHO: 4-(2-pyridyl)benzaldehyde; dppe:
-1,2-bis(diphenylphosphino)ethene) shows satisfactory TPA properties and long lifetimes (up to 1 μs). The emission intensities and lifetimes of
are viscosity-dependent, which is mainly attributed to the configurational changes in the diphosphine ligand as proved by
H NMR spectra.
displays potent cytotoxicity, and mechanism investigations show that it can accumulate in mitochondria and induce apoptotic cell death. Moreover,
can induce mitochondrial dysfunction and monitor the changes in mitochondrial viscosity simultaneously in a real-time and quantitative manner
TPPLIM. Upon
treatment, a time-dependent increase in viscosity and heterogeneity is observed along with the loss of membrane potential in mitochondria. In summary, our work shows that multifunctional phosphorescent metal complexes can induce and precisely detect microenvironmental changes simultaneously at the subcellular level using TPPLIM, which may deepen the understanding of the cell death mechanisms induced by these metallocompounds.
Direct methanol fuel cells (DMFCs) are among the most promising portable power supplies because of their unique advantages, including high energy density/mobility of liquid fuels, low working ...temperature, and low emission of pollutants. Various metal‐based anode catalysts have been extensively studied and utilized for the essential methanol oxidation reaction (MOR) due to their superior electrocatalytic performance. At present, especially with the rapid advance of nanotechnology, enormous efforts have been exerted to further enhance the catalytic performance and minimize the use of precious metals. Constructing multicomponent metal‐based nanocatalysts with precisely designed structures can achieve this goal by providing highly tunable compositional and structural characteristics, which is promising for the modification and optimization of their related electrochemical properties. The recent advances of metal‐based electrocatalytic materials with rationally designed nanostructures and chemistries for MOR in DMFCs are highlighted and summarized herein. The effects of the well‐defined nanoarchitectures on the improved electrochemical properties of the catalysts are illustrated. Finally, conclusive perspectives are provided on the opportunities and challenges for further refining the nanostructure of metal‐based catalysts and improving electrocatalytic performance, as well as the commercial viability.
Efficient catalysts are critical for the electrocatalytic oxidation reaction of methanol. Metal‐based anode catalysts with well‐defined nanoarchitectures and optimal chemical compositions can provide superior performance with lower costs. The possible effects, challenges, and future development are elaborately discussed to shed light on the further design of metal‐based anode catalysts for the methanol electro‐oxidation reaction, leading to a renewable energy supply future.
The integration of wind power requires additional operating reserves to cope with the uncertainty in power system operation. Previous research shows that the uncertainty of the wind power forecast ...varies with the level of its output. Therefore, allocating reserves dynamically according to the specific distribution of the wind power forecast would benefit system scheduling. This paper presents a statistical model to formulate the conditional distribution of forecast error for multiple wind farms using copula theory. The proposed model is tested using a set of synchronous data of wind power and its day-ahead forecast. It is then utilized in a stochastic unit commitment model to simulate the day-ahead and real-time scheduling of the modified IEEE RTS-79 system integrating wind power. The results show that scheduling reserves dynamically according to the modeled conditional forecast error reduces the probability of reserve deficiency while maintaining the same level of operating costs.
•We consider both fuel costs and emissions, and find the best compromise value.•We introduce differential evolution operator into quantum particle swarm optimization (QPSO).•We introduce crossover ...operator into quantum particle swarm optimization (QPSO).•Adaptive control is adopted for crossover probability.
Consumption of traditional fossil energy has promoted rapid economic development and caused effects such as climate warming and environmental degradation. In order to solve the problem of environmental economic dispatch (EED), this paper proposes a DE-CQPSO (Differential Evolution-Crossover Quantum Particle Swarm Optimization) algorithm based on the fast convergence of differential evolution algorithms and the particle diversity of crossover operators of genetic algorithms. In order to obtain better optimization results, a parameter adaptive control method is used to update the crossover probability. And the problem of multi-objective optimization is solved by introducing a penalty factor. The experimental results show that: the evaluation index and convergence speed of the DE-CQPSO algorithm are better than QPSO (Quantum Particle Swarm Optimization) and other algorithms, whether it is single-objective optimization of fuel cost and emissions or multi-objective optimization considering both optimization objectives. A good compromise value is verified, which verifies the effectiveness and robustness of the DE-CQPSO algorithm in solving environmental economic dispatch problems. The study provides a new research direction for solving environmental economic dispatch problems. At the same time, it provides a reference for the reasonable output of the unit to a certain extent.
Phosphorescent metal complexes are a new kind of multifunctional antitumor compounds that can integrate imaging and antitumor functions in a single molecule. In this minireview, we summarize the ...recent research progress in this field, concentrating on the theranostic applications of phosphorescent iridium(
iii
), ruthenium(
ii
) and rhenium(
i
) complexes. The molecular design that affords these complexes with tumour- or subcellular organelle-targeting properties is elucidated. The potential of these complexes to induce and monitor the dynamic behavior of subcellular organelles and the changes in microenvironment during the process of therapy is demonstrated. Moreover, the potential and advantages of applying new technologies, such as super-resolution imaging and phosphorescence lifetime imaging, are also described. Finally, the challenges faced in the development of novel theranostic metallo-anticancer complexes for possible clinical translation are proposed.
The recent development in phosphorescent iridium, ruthenium and rhenium complexes as theranostic anticancer agents is summarized.
Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide due to a high rate of tumour metastasis and disease recurrence. In physiological conditions, tetraspanins interact with ...specific partner proteins in tetraspanin‐enriched microdomains and regulate their subcellular localization and function. However, the function of Tspan5 in pathological processes, particularly in cancer biology and its clinical significance, are still unclear. Here, we describe that a high expression of Tspan5 is significantly associated with some clinicopathological features including invasive length, vascular invasion, clinical stage and poor overall survival of HCC patients. Alterations of Tspan5 expression by lentivirus transductions in HCC cells demonstrated that Tspan5 promotes wound healing and cell migration in vitro and tumour metastasis of HCC cells in vivo. Mechanistic studies revealed that Tspan5 promoted cell migration and tumour metastasis by increasing the enzymatic maturation of ADAM10 and activating Notch signalling via the increase of the cleavage of the Notch1 receptor catalysed by the γ‐secretase complex. Activation of Notch signalling by Tspan5 was shown further to enhance the epithelial–mesenchymal transition (EMT) and actin skeleton rearrangement of tumour cells. In clinical HCC samples, Tspan5 expression is strongly correlated with many key molecules acting in Notch signalling and EMT, highlighting the role of Tspan5 in the regulation of Notch signalling, EMT and tumour metastasis of HCC. Our findings provide new insights into the mechanism of tumour metastasis and disease progression of HCC and may facilitate the development of novel clinical intervention strategies against HCC.
We demonstrated that Tspan5 promotes the enzymatic maturation of ADAM10 and activates Notch signalling. The γ‐secretase complex catalyses the cleavage of Notch1 for the release of NICD, which is then translocated to the nucleus where it activates Notch target gene transcription. By activating Notch signalling, Tspan5 promoted epithelial–mesenchymal transition, actin skeleton rearrangement, tumour migration and metastasis of HCC, resulting in poor patient survival.
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