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Magnetoresponsive, methacrylate-based 3D polymer networks containing hydrophilic/thermoresponsive, hydrophilic/pH-responsive and hydrophobic/metal chelating functionalities and oleic acid-coated magnetite nanoparticles, have been synthesized by conventional crosslinking radical polymerization and further evaluated as adsorbents for the removal of U(VI) ions from aqueous media. The adsorption properties of the networks prior and after magnetization regarding U(VI) ion removal from aqueous solutions of varying acidity and initial U(VI) concentration have been investigated. The effect of pH on the interaction of the adsorbents with U(VI) ions was shown to differ dramatically depending on solid phase composition, due to the fact that in the magnetite-loaded network, the Fe3O4 nanoparticles act as buffers by binding solution protons. Nevertheless, U(VI) adsorption on both types of adsorbents follows the Langmuir adsorption isotherm and the value of their maximum adsorption capacity is qmax = ∼0.02 mol kg−1 showing no statistically significant differences. The magnetic properties of these materials make their removal and adsorbed uranium separation from the aqueous phase quite simple by using an external magnetic field. © 2017 Elsevier Ltd 97 138 146 138-146

Colloidal polyvinylpyrrolidone-stabilized Pd nanoparticles were embedded within 1,2-bis(2-iodoethoxy)ethane (BIEE)-crosslinked poly(2-dimethylamino)ethyl methacrylate homopolymer networks with defined structural characteristics. In the presented synthetic approach, the crosslinking step is realised in ambient conditions, thus avoiding nanoparticle agglomeration phenomena. These 3D polymer-based nanocomposite networks were evaluated as heterogeneous catalysts for Heck, Suzuki-Miyaura and Sonogashira coupling reactions. High catalytic activity and reusability was demonstrated in Heck reactions, substrate-specific outcomes were observed in Sonogashira couplings, while poor reactivity was observed in Suzuki-Miyaura couplings. The existing diversity in material structure and composition allows for further improvements leading to highly stable and robust 3D polymer-based nanocomposite heterogeneous catalysts that could find use in a wide range of transition metal-catalysed organic reactions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1 2635 2641 2635-2641

The mechanical properties of structurally-defined magnetoactive polymer (co)networks synthesized from well-defined poly(2-dimethylamino)ethyl methacrylate (poly(DMAEMA)) homopolymers and diblock copolymers of poly(DMAEMA) with the hydrophobic n-butyl methacrylate (BuMA) were measured in compression. Magnetic nanoparticle composition varied from 0 to 30% wt and caused a 6-fold increase in the Young's modulus of the homopolymer networks (2.91 vs. 18.62 kPa) and a 12-fold increase in the modulus of diblock copolymer networks (0.76 vs. 9.1 kPa), with homopolymers being stiffer. Mathematical modeling revealed an exponential constitutive equation to predict accurately the mechanical response of the polymers. Furthermore, experiments were performed for the poroelastic behavior of the materials and their hydraulic conductivity was found to be independent of magnetic loading and network structure. In conclusion, the incorporation of magnetic nanoparticles strengthened the (co)network structure, while the synthetic approach employed for the DMAEMA-b-BuMA formation retained the linear, non-crosslinked architecture of BuMA, resulting in less stiff structures. This journal is © The Royal Society of Chemistry 2015. 5 20011 20019 20011-20019

After a timing preoperative staging, treatment of resectable pancreatic adenocarcinoma (PDAC) includes surgery and adjuvant therapies, the former representing the initial therapeutic option and the latter aiming to reduce the incidence of both distant metastases (chemotherapy) and locoregional failures (chemoradiotherapy). Herein, we provide a critical overview on the role of multimodal treatment in PDAC and on new opportunities related to current more active poli-chemotherapy regimens, targeted therapies, and the more recent immunotherapy approaches. Moreover, an analysis of pathological markers and clinical features able to help clinicians in the selection of the best therapeutic strategy will be discussed. Lastly, the role of neoadjuvant treatment of initially resectable disease will be considered mostly in patients whose malignancy shows morphological but not clinical or biological criteria of resectability. Depending on the results of these investigational studies, today a multidisciplinary approach can offer the best address therapy for these patients.

Mechanisms of acquired resistance to trastuzumab-based treatment in gastric cancer are largely unknown. In this study, we analyzed 22 pairs of tumor samples taken at baseline and post-progression in patients receiving chemotherapy and trastuzumab for advanced HER2-positive [immunohistochemistry (IHC) 3+ or 2+ with in-situ hybridization (ISH) amplification] gastric or gastroesophageal cancers. Strict clinical criteria for defining acquired trastuzumab resistance were adopted. Loss of HER2 positivity and loss of HER2 over-expression were defined as post-trastuzumab IHC score

Erratum for Natural History of Non-Small-Cell Lung Cancer with Bone Metastases

Sn:In2O3 nanowires have been grown by the vapor liquid solid mechanism on Si, Ni, Mo, and C fibers. These were used to obtain Sn:In2O3/NiS2 core-shell nanowires by the deposition of 10 nm Ni over the Sn:In2O3 nanowires followed by post growth processing under H2S between 100 and 200 °C. The Sn:In2O3/NiS2 nanowires have diameters of ≈100 nm and lengths up to ≈100 μm and consist of cubic bixbyite Sn:In2O3 surrounded by 3 nm NiS2 crystalline quantum dots with a cubic crystal structure. Higher temperatures of 300-500 °C result in the formation of NiS2 quantum dots and cubic In3S4 branches around the Sn:In2O3. We find that the p-type NiS2 in contact with n-type Sn:In2O3 NWs gives rectifying current-voltage (IV) characteristics due to the formation of a p-n heterojunction with a straddling type band alignment where electrons are confined to the n-type Sn:In2O3 core and holes in the p-type NiS2, as shown by self-consistent Poisson-Schrödinger calculations in the effective mass approximation. The gas evolution of O2 and H2 was measured using the Sn:In2O3/NiS2 nanowires as the anode and Pt as the cathode in a two-compartment photoelectrochemical cell containing 1 M KOH (aq) and 0.5 M H2SO4 (aq), respectively, under light of 1 sun. We obtain 7.8 μL/min of O2 and 15.0 μL/min of H2 at an overpotential of 0.2 V and 25 °C from the Sn:In2O3/NiS2 nanowires on C. These are ≈35% larger than those obtained from plain Sn:In2O3 nanowires attributed to the existence of the p-n junction. © 2017 American Chemical Society. 121 27839 27848 27839-27848

Core-shell PbS/Sn:In2O3 and branched PbIn2S4/Sn:In2O3 nanowires have been obtained via the deposition of Pb over Sn:In2O3 nanowires and post growth processing under H2S between 100 C-200 C and 300 C-500 C respectively. The PbS/Sn:In2O3 nanowires have diameters of 50-250 nm and consist of cubic PbS and In2O3 while the PbIn2S4/Sn:In2O3 nanowires consist of PbIn2S4 branches with diameters of 10-30 nm and an orthorhombic crystal structure. We discuss the growth mechanisms and also show that the density of electrons in the n-type Sn:In2O3 core is strongly dependent on the thickness of the p-type PbS shell, which must be smaller than 30 nm to prevent core depletion, via the self-consistent solution of the Poisson-Schr�dinger equations in the effective mass approximation. The PbS/Sn:In2O3 and PbIn2S4/Sn:In2O3 nanowire networks had resistances of 100-200 Ω due to the large carrier densities and exhibited defect related photoluminescence at 2.2 eV and 1.5 eV respectively. We show that PbS in contact with polysulfide electrolyte has ohmic like behavior but the PbS/Sn:In2O3 nanowires gave, rectifying current voltage characteristics as a counter electrode in a quantum dot sensitized solar cell using a conventional ITO/TiO2/CdS/CdSe photo anode, an open circuit voltage of ≈0.5 V, and short circuit current density of ≈1 mA cm-2. In contrast the branched PbIn2S4/Sn:In2O3 nanowires exhibited a higher current carrying capability of ≈7 mA cm-2 and higher power conversion efficiency of ≈2%. � 2016 IOP Publishing Ltd. 28

The fabrication of magnetoactive fibrous nanocomposite membranes based on poly(vinyl pyrrolidone) (PVP), poly(L-lactide) (PLLA) and pre-formed oleic acid coated magnetite nanoparticles (OA Fe3O4) is presented. The aforementioned materials have been prepared by means of the electrospinning technique following a single-step fabrication process. The PVP/PLLA/OA Fe 3O4 nanocomposite membranes were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that provided information on the fiber diameters as well as on the morphological and dimensional characteristics of the OA Fe3O4 nanoparticles embedded within the fibers. The thermal stability of these materials was evaluated by means of thermal gravimetric analysis (TGA) measurements. Finally, vibrational sample magnetometry (VSM) analysis disclosed superparamagnetic behavior at room temperature. The combination of the hydrophilic, biocompatible and photo-crosslinkable PVP with the biodegradable PLLA and the superparamagnetic OA Fe3O4 nanoparticles within these materials allows for the future development of crosslinked fibrous magnetoactive nanocomposites exhibiting high stability in aqueous solutions, with potential use in biomedical and environmental applications. © 2013 Elsevier B.V. All rights reserved. 352 30 35 30-35