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The combination of chemotherapy and gene therapy has been indicated as a promising approach for cancer therapy. However, this combination strategy is still faced a challenge by the lack of suitable carriers to co-loaded chemotherapeutic drug and gene into one single nanoplatform. In this study, a tumor-targeted HC/pIL-12/polyMET micelleplexes were developed for the co-loading and co-delivery of cisplatin (CDDP) and plasmid encoding interleukin-12 gene (pIL-12), which would be utilized to generate synergistic actions through chemotherapy sensitization and microenvironment modulation. The HC/pIL-12/polyMET exhibited desirable particle size, superior serum stability, effective intracellular CDDP release and pIL-12 transfection efficiency. More important, the HC/pIL-12/polyMET generated the enhanced LLC cell proliferation inhibition and apoptosis induction efficiency. The long-circulating HC/pIL-12/polyMET micelleplexes promoted the accumulation of CDDP and pIL-12 in tumor site, which resulted in significantly inhibiting the growth of lung cancer, and prolonging the overall survival of tumor-bearing mice. The underlying immune mechanism demonstrated the combination of CDDP and pIL-12 activated immune effector cells to release IFN-γ and induced M1-type differentiation of tumor-related macrophages, thereby generating synergistic chemoimmunotherapy effect. Taken together, this study may provide an effective strategy for drug/gene co-delivery and cancer chemoimmunotherapy. Chemoimmunotherapy has been indicated as an approach to improve efficacy of cancer therapy. Herein, a tumor-targeted micelleplexes (HC/pIL-12/polyMET) were developed for the co-delivery of cisplatin (CDDP) and plasmid encoding IL-12 gene (pIL-12), which can employ the synergistic effects through chemotherapy sensitization and microenvironment modulation. The HC/pIL-12/polyMET exhibited desirable particle size, superior serum stability, high gene transfection efficiency and antitumor activity on tumor cell proliferation inhibition and apoptosis induction. More importantly, the long-circulating HC/pIL-12/polyMET micelleplexes could effectively accumulate in tumor sites and then rapidly release the CDDP and pIL-12, significantly inhibit the growth of lung cancer. This strategy provides a new concept for chemo-gene combination with a strengthened overall therapeutic efficacy of chemoimmunotherapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Galvanic coupling theory is traditionally adopted to explain initialization of localized dissolution; however, in present study, the conductivity of LaAlO 3 and La 2 O 2 S inclusions was calculated using first-principles to predict whether galvanic corrosion occurs or not. Further, influences of these inclusions on localized corrosion were examined by scanning electron microscope, energy dispersive spectrometer, electron back scattered diffraction, and immersion experiments. It was found that no galvanic coupling occurred between LaAlO 3 and the matrix, and microcrevices are the main responsible for localized corrosion. Except microcrevices, an intrinsic potential difference between La 2 O 2 S and the matrix also contributes to the initialization of localized corrosion. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract A series of core-shell SiO 2 @C microspheres with different size of SiO 2 microspheres and thickness of conductive carbon black (CB) were prepared via carbothermal reduction method. The samples were characterized by SEM, TEM, XRD, XPS and Raman spectroscopy analyses. When the size of SiO 2 microspheres or CB thickness was changed, the as-synthesized SiO 2 @C composites possessed diverse reflection loss (RL). Among, the electromagnetic wave (EMW) absorption performance of S-2 composite was optimal and its minimum reflection loss (RL min) was up to −39.7 dB at the thickness of 3.8 mm and the effective bandwidth (RL ≤ −10 dB, 90% absorption) covered 1.3 GHz. Hence, it is the size of SiO 2 microspheres and CB content that can tune the EMW absorption performance of the SiO 2 @C composites, which makes SiO 2 @C composites rather promising EMW absorption materials. Graphical abstract Unlabelled Image Highlights • The performance of samples can be adjusted by changing the size of SiO 2 and thickness of carbon black. • Such good performance is indeed superior to most carbon absorbers ever reported. • The SiO 2 @C composites can be advantageous candidate materials in many fields. [ABSTRACT FROM AUTHOR]

Uniform core-shell SiO 2 @Fe 3 O 4 @C composite was prepared by a one-step hydrothermal method by using SiO 2 nanosphere as template. The structure and electrochemical performance of sample were characterized by means of modern analytical techniques. Electrochemical cyclic voltammetry showed that SiO 2 @Fe 3 O 4 @C composite had good electrochemical reversibility and stability. Under the constant current density of 100 mA g −1 , the capacitance of sample still reaches to 140 mA h g −1 after 100 cycles. The superior electrochemical performance of as-prepared SiO 2 @Fe 3 O 4 @C was attributed to the mesoporous carbon layer and Fe 3 O 4 nanoparticles, indicating that SiO 2 @Fe 3 O 4 @C was a kind of superior anode material for lithium-ion battery. Therefore, the SiO 2 @Fe 3 O 4 @C has a promising application in the filed of lithium-ion battery. [ABSTRACT FROM AUTHOR]

In Al Ti Mg killed steels, the use of complex deoxidation products, which act as heterogeneous nucleation sites for fine intragranular ferrite, has been acknowledged as an effective way for grain refinement. In this study, we investigated the interaction between Mn solute atoms and different oxide inclusions (such as MgO, MgTi 2 O 4 , MgTiO 3 , Ti 2 O 3 , Ti 3 O 5 , Al 2 O 3 , MgAl 2 O 4 ) experimentally and using first-principles calculations, to identify the oxides that can effectively lead to the formation of local Mn-depleted zones promoting the nucleation of intragranular ferrite. The results show that MgTi 2 O 4 , MgTiO 3 are effective for partition of Mn atoms into oxides, while MgO, Al 2 O 3 , MgAl 2 O 4 are ineffective for the formation of local Mn-depleted zones. Furthermore, the calculations show that Mn atoms exist as a simple solute by replacing Mg atoms in MgO, MgTi 2 O 4 and MgTiO 3 . Except by forming complex Ti-Mn oxides, such as MnTi 2 O 4 and MnTiO 3 , Mn atoms can also exist as a simple solute in Ti 2 O 3 by occupying vacancy positions in their crystals. Ti 3 O 5 oxides cannot absorb Mn atoms by replacing Ti atoms in it, meanwhile, the occupying vacancy pattern is not the main reason for Ti 3 O 5 oxides absorb Mn atoms. [ABSTRACT FROM AUTHOR]

Abstract: A trifunctional 1,9-dithiophenalenylium salt with benzene spacer has been prepared as the precursor for a phenalenyl-based high spin radical. Electrochemical studies show that this salt undergoes two three-electron reduction steps and generate its corresponding neutral radical, which has been studied by quantum chemical calculations. The investigation of the spin density distribution of the radical revealed that the spin and electronic properties of molecules based on phenalenyl systems are strongly influenced by intramolecular topology connection. [Copyright &y& Elsevier]

Abstract: Stable phenalenyl (PLY) radicals without sterically bulky substituents need to be synthesized for application as neutral organic molecular conductors. Verdazyl radicals, which have high stability even without sterically bulky substituents, were combined with PLY radicals to produce two novel radicals. The stability of the dimethylthiourea substituted PLY radical is supported by the experimental results and quantum chemical calculations. [Copyright &y& Elsevier]

• In deoxidized Al steel, the Ti-Mg composite deoxidization treatment can obtain finer and more dispersed non-metallic inclusions, promoting ferrite nucleation and significantly improving the performance of the welding heat-affected zone. At the same time, Mg treatment can modify alumina and sulfide inclusions and reduce their hazards. It is the first time to study the galvanic corrosion of Al-Ti-Mg killed steel induced by inclusions. • Researchers concluded that the composite inclusions have lower surface potentials than the matrix by traditional experiment measurements, which induces pitting corrosion. This opinion cannot explain why in the same composite oxide inclusions, one part did not dissolve, while the other part dissolved prior to the matrix in the pitting corrosion process. It is difficult to determine by traditional experimental method which inclusions in composite inclusions play a greater role in the process of pitting corrosion. In this work, we determined which inclusions in composite inclusions play a greater role in the process of galvanic corrosion, and explained why in the same composite oxide inclusions, one part did not dissolve, while the other part dissolved prior to the matrix in the pitting corrosion process. In order to reveal the mechanism of galvanic pitting corrosion initiation induced by typical complex inclusions in Al-Ti-Mg deoxidized high strength pipeline steel, first-principles calculations, combining with immersion tests, scanning electron microscopy was used to study the correlation between electronic work function and galvanic corrosion of Al-Ti-Mg killed steel. The results show that MnS inclusions act as anodes in the electrochemical environment, preferentially corroding and dissolving; MgAl 2 O 4 and Al 2 O 3 inclusions act as cathodes, leading to the corrosion of Fe matrix; different end planes of MgTiO 3 and MgTi 2 O 4 act as both anodes and cathodes, but they have little effect on pitting corrosion. Microcrevices on the MgTiO 3 and MgTi 2 O 4 inclusions boundary are the main cause of matrix dissolution. [ABSTRACT FROM AUTHOR]

• Mechanism of Yttrium composite inclusions on the localized corrosion of pipeline steels was studied which was seldomly studied in the literature. • Mechanism of internal activity difference of inclusions on pitting corrosion is revealed from atomic scale. • Mechanism of the preferential dissolution position was studied from the point of view of the Micro battery between Yttrium inclusions and matrix. In order to solve the problem of where, why, and how to start pitting, it is necessary to study the influence of different dissolution activity of the internal heterogeneous structures of the complex inclusions. In this paper, mechanism of internal activity difference of two typical Yttrium composite inclusions on pitting corrosion is revealed from atomic scale by using immersion test, FE-SEM/EDS analysis and first-principles calculations. The results show that, for Mg-Y-S composite inclusions, pitting potential is lower than that of the matrix, therefore, The matrix around the composite inclusions dissolves preferentially; for Y-S-O composite inclusions with core-shell structure, Y-O inclusions in the shell are deformed and cracked due to the internal stress of the matrix and Y-S during the immersion process, resulting in the simultaneous dissolution of inclusions and steel matrix. [ABSTRACT FROM AUTHOR]

Coiled carbon nanotubes (CCNTs) were coated by CoFe 2 O 4 (CFO) nanoparticles to form the CCNTs/CFO composites. The phase composition, morphology, electrical and magnetic performances of the composites were characterized by means of modern analytical techniques. The results indicated that the conductivity and magnetic performances of the samples were related to their compositions. The CCNTs/CFO composite with ω CCNT / ω CFO of 0.4 exhibited the best microwave absorption property in the prepared samples, whose minimum reflection loss was about −14 dB in the frequency range of 2–18 GHz for a layer of 2.5–3.0 mm thickness, and the available bandwidth corresponding to RL less than −10 dB can reach 4.0 GHz. Hence, the obtained composite could be used as a new candidate for selective frequency shielding and lightweight microwave absorbing material. [ABSTRACT FROM AUTHOR]

Graphical abstract Schematic illustration on proposed multidrug resistance (MDR) reversion mechanisms of paclitaxel/hyaluronic acid-deoxycholic acid-histidine (PTX/HA-DOCA-His) micelles in MCF-7/Adr cells. Highlights • CD44 receptor and endosome pH sensitive dual-targeted HA-DOCA-His micelles were developed. • Intracellular uptake and cytotoxicity study confirmed the multidrug resistance reversion efficacy of HA-DOCA-His micelles. • HA-DOCA-His micelles exhibited longer circulation time and larger AUC. • HA-DOCA-His micelles demonstrated excellent therapeutic efficacy on MDR tumors. Abstract The drug efflux mediated by P-glycoprotein (P-gp) transporter is a major factor responsible for multidrug resistance (MDR) of paclitaxel (PTX). The efficient intracellular PTX delivery is a promising strategy for overcoming the MDR of tumor cells. A CD44 receptor targeting and endosome-pH sensitive dual functionalized hyaluronic acid-deoxycholic acid-histidine (HA-DOCA-His) micellar formulation was developed to overcome MDR, and a CD44 receptor targeting hyaluronic acid-deoxycholic acid (HA-DOCA) micelles was used as a comparison. Compared with Taxol solution and HA-DOCA micelles, the cytotoxicity of PTX loaded in HA-DOCA-His micelles against drug-resistant tumor cells was improved significantly and possessed superior MDR-overcoming performance; this phenomenon is due to the increased intracellular PTX delivery by CD44 receptor-mediated endocytosis pathway and endosome-pH sensitivity-mediated PTX triggering release. Upon pharmacokinetic study, PTX/HA-DOCA-His micelles demonstrated longer blood circulation time, larger AUC, decreased V d and CL than the Taxol solution. More importantly, PTX/HA-DOCA-His micelles were more effective in tumor growth inhibition in MCF-7/Adr tumor-bearing mice compared with PTX/HA-DOCA micelles and Taxol solution. Dual targeting strategy-functionalized HA-DOCA-His micelles demonstrated excellent MDR-reversing ability for therapeutic efficacy and improvement on MDR tumors, thereby providing an effective targeting strategy for PTX delivery of nano-drug delivery system in MDR cancer chemotherapy. [ABSTRACT FROM AUTHOR]

[Display omitted] In recent years, polymorphic transformation involved in media milling has become a key factor in inducing the instability of nanosuspensions (NSs). The variation trend of microhydrodynamic parameters, including milling intensity factor (F), can be observed under different milling conditions. Therefore, this study first referenced the microhydrodynamic model to explore how formulations and process parameters affect Irbesartan (IRB) form A crystallinity during wet media milling. As a result, the crystallinity of form A was affected by the intermolecular interactions between drug particles and stabilizers. The crystallinity of form A decreased with decreasing drug loading, increasing stirrer speed and bead loading, which depended on the role of F. Milling could promote the transformation from a 1H to 2H tetrazole ring with stabilizers containing –OH, and form B was changed to form A and finally to an amorphous state. Molecular modelling shows that forms A and B are ductile and fragile materials, respectively, and both present anisotropy. When milling beads hit both polymorphs paralleling to the (0 1 0) surface, the bead-bead collisions are more helpful in fracturing IRB particles. The results of this study may provide a foundation for controlling crystal transformation and obtaining ideal crystal forms. [ABSTRACT FROM AUTHOR]

The dynamics of multiple ecosystem functions (that is, multifunctionality) are closely associated with biodiversity, often show positive relationships, but the dynamics of the biodiversity multifunctionality relationship along soil profiles remain unclear. Eutrophication significantly affects biodiversity and soil functions, whereas the mechanisms underlying the impact of nitrogen addition on the biodiversity multifunctionality relationship are poorly understood. Here, we conducted a common garden experiment manipulating plant diversity and nitrogen addition to quantify the effects of biodiversity on soil multifunctionality in the topsoil and subsoil under different nitrogen addition levels. We showed that nitrogen addition had a minor impact on soil multifunctionality but weakened the positive biodiversity multifunctionality relationship. We also found that the positive plant diversity effect on soil multifunctionality decreased with soil depths, resulting in a weaker biodiversity multifunctionality relationship in the subsoil. The weak biodiversity multifunctionality relationship in the subsoil was caused by weakening the relationship between aboveground biomass and soil multifunctionality; nitrogen addition weakened the biodiversity multifunctionality relationship through the attenuation of the association of aboveground biomass and soil microbes with multifunctionality. Our study demonstrates that nitrogen addition undermines the biodiversity soil multifunctionality relationship and the relationship is weakened along the soil profiles, suggesting that Earth system models must represent these heterogeneous soil dynamics to accurately predict future feedbacks to global changes. • N addition weakens biodiversity soil multifunctionality (SMF) relationships (BMR). • Decrease in aboveground biomass (AGB) inputs leads to a weak BMR in the subsoil. • Weak associations of AGB and soil microbes with SMF weaken the BMR under N addition. [ABSTRACT FROM AUTHOR]