First evidence of in vitro cytocompatibility of SiC/SiO2 core-shell nanowires is reported. Different internalization mechanisms by adenocarcinomic alveolar basal epithelial cells, monocytic cell line derived from an acute monocytic leukemia, breast cancer cells, and normal human dermal fibroblasts are shown. The internalization occurs mainly for macropinocytosis and sporadically by direct penetration in all cell models considered, whereas it occurred for phagocytosis only in monocytic leukemia cells. The cytocompatibility of the nanowires is proved by the analysis of cell proliferation, cell cycle progression, and oxidative stress on the cells treated with NWs as compared to controls. Reactive oxygen species generation was detected as an early event that then quickly run out with a rapid decrease only in adenocarcinomic alveolar basal epithelial and human dermal fibroblasts cells. In all the cell lines, the intracellular presence of NWs induce the same molecular events but to a different extent: peroxidation of membrane lipids and oxidation of proteins. The NWs do not elicit either midterm (72 h) or long-term (10 days) cytotoxic activity leading to irreversible cellular damages or death. Our results are important in view of a possible use of SiC/SiO2 core-shell structures acting as biomolecule-delivery vectors or intracellular electrodes.

The development of innovative nanosystems opens new perspectives for multidisciplinary applications at the frontier between materials science and nanomedicine. Here we present a novel hybrid nanosystem based on cytocompatible inorganic SiC/SiOx core/shell nanowires conjugated via click-chemistry procedures with an organic photosensitizer, a tetracarboxyphenyl porphyrin derivative. We show that this nanosystem is an efficient source of singlet oxygen for cell oxidative stress when irradiated with 6 MV X-Rays at low doses (0.4–2 Gy). The in-vitro clonogenic survival assay on lung adenocarcinoma cells shows that 12 days after irradiation at a dose of 2 Gy, the cell population is reduced by about 75% with respect to control cells. These results demonstrate that our approach is very efficient to enhance radiation therapy effects for cancer treatments.

o-Biaryl carbaldeydes and ketones are obtained through the one-pot reaction of o-aryl iodides with o-bromobenzyl alcohols under the catalytic action of Pd and norbornene, in the presence of a base. The same reaction can also give dibenzopyrans by Pd and norbornene catalysis with a different termination, leading to C-O ring closure. In both cases the process first leads to a five-membered palladacycle, which controls C-C coupling, then to a seven-membered oxapalladacycle, which gives aldehydes and ketones or dibenzopyrans.

Monodispersed Fe3O4 nanoparticles with comparable size distributions have been synthesized by two different synthesis routes, co-precipitation and thermal decomposition. Thanks to the different steric stabilizations, the described samples can be considered as a model system to investigate the effects of magnetic dipolar interactions on the aggregation states of the nanoparticles. Moreover, the presence of magnetic dipolar interactions can strongly affect the nanoparticle efficiency as a hyperthermic mediator. In this paper, we present a novel way to visualize and map the magnetic dipolar interactions in different kinds of nanoparticle aggregates by the use of Lorentz microscopy, an easy and reliable in-line electron holographic technique. By exploiting Lorentz microscopy, which is complementary to the magnetic measurements, it is possible to correlate the interaction degrees of magnetic nanoparticles with their magnetic behaviors. In particular, we demonstrate that Lorentz microscopy is successful in visualizing the magnetic configurations stabilized by dipolar interactions, thus paving the way to the comprehension of the power loss mechanisms for different nanoparticle aggregates.

Magnetic shape memory materials hold a great promise for next‐generation actuation devices and systems for energy conversion, thanks to the intimate coupling between structure and magnetism in their martensitic phase. Here novel magnetic shape memory free‐standing nanodisks are proposed, proving that the lack of the substrate constrains enables the exploitation of new microstructure‐controlled actuation mechanisms by the combined application of different stimuli–i.e., temperature and magnetic field. The results show that a reversible areal strain (up to 5.5%) can be achieved and tuned in intensity and sign (i.e., areal contraction or expansion) by the application of a magnetic field. The mechanisms at the basis of the actuation are investigated by experiments performed at different length scales and directly visualized by several electron microscopy techniques, including electron holography, showing that thermo/magnetomechanical properties can be optimized by engineering the martensitic microstructure through epitaxial growth and lateral confinement. These findings represent a step forward toward the development of a new class of temperature‐field controlled nanoactuators and smart nanomaterials.

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ContentSEM of the Na 2 CO 3 utilized Preparation of the stock solutions and Schlenk tube Kinetic test for styrene ARGET ATRP with ascorbic acid/Na 2 CO 3 GPC traces of PSs: effect of reaction time and catalyst amount MALLS analyses GPC traces of PSs: effect of dilution with monomer Effect of the EtOAc/EtOH ratio on the polymerization Kinetic investigation Instability of the yellow chromophore Experimental procedure for the isolation of TPMA Reduction of CuCl 2 /TPMA by Na 2 CO 3 in EtOAc/EtOH Linear sweep voltammetry Kinetic comparison between ARGET ATRP with and without ascorbic acid Replacement of Na 2 CO 3 with nitrogen bases Linear sweep voltammetry in S/t-BuOAc/t-BuOH

Closure. -An excess of norbornene has to be used, the molar ratio of norbornene to Pd varies between 5:1 to 20:1. The proposed reaction pathway involves a five-and a seven-membered palladacycle intermediate which afford the oxidation to aldehyde in one ring of the biarylunit and the reduction of the C-Pd bond in the other one. -(MOTTI, E.; DELLA CA, N.; XU, D.; PIERSIMONI, A.; BEDOGNI, E.; ZHOU, Z.-M.; CATELLANI*, M.; Org. Lett. 14 (2012) 22, 5792-5795, http://dx.doi.org/10.1021/ol302889t ; Dip. Chim., Univ. Parma, I-43124 Parma, Italy; Eng.) -R. Simon 14-095