Application of empirical modelling in multi-layers membrane manufacturing

Multistructured membranes based on ultrafine fibers of polymethylmethacrylate-co-methacrylic acid (PMMA-co-MAA) and TiO₂ nanoparticles have been obtained by electrohydrodynamic (EHD) technologies, for active filter media manufacturing. Process optimization of the nanofibers based layers has been investigated by response surface methodology (RSM) in order to predict the domain of the parameters where the smallest fiber diameter can be achieved. A quantitative relationship between electrospinning parameters and the responses (mean diameter and standard deviation) was established and then the final multi-layers structure of nanofibers and nanoparticles has been achieved for a controlled and robust process. The nanostructured membranes have been characterized by SEM imaging, EDAX, TGA analysis and water vapour permeability and their photocatalytic activity has been tested on VOCs degradation.     

Temperature‐dependent coefficient of thermal expansion (CTE) of injection molded,short‐glass‐fiber‐reinforced polymers

A deep understanding of the anisotropic, composite‐, geometry‐, and temperature‐dependent coefficient of thermal expansion (CTE) of short‐fiber‐reinforced polymers is often needed in material development and at early stages of the design process of injection molded parts. Usually, the data available does not reflect the complex behavior and the knowledge about the influences and interactions are missing. This paper deals with a method for calculating the composite‐, geometry‐, and temperature‐dependent anisotropic CTE of parts made from short‐fiber reinforced polymers without respectively low preload to create an understanding of its origins and influential factors. Here, a good accordance between the measurements and calculations was achieved. POLYM. ENG. SCI., 55:2661–2668, 2015. © 2015 Society of Plastics Engineers     

High SPARC Expression Starting from Dysplasia,Associated with Breast Carcinoma,Is Predictive for Bone Metastasis without Enhancement of Plasma Levels

In order to become established in the skeleton, metastatic cells disseminating from the breast carcinoma need to acquire organ-specific traits. There are no effective predictors for who will develop bone metastasis to guide long-term predictive therapy. Our purpose was to individuate events critical for bone colonization to make a molecular classification of breast carcinoma useful for bone-metastasis outcome. In dysplasia adjacent to carcinoma and in pair-matched specimens of bone metastasis we examined SPARC expression and localization as well as Endothelin 1/ET_AR signals by immunohistochemistry, and the evaluation of plasma levels of SPARC by ELISA was also performed. In patients with breast carcinoma metastasizing to bone, SPARC and Endothelin 1/ET_AR axis were highly expressed from dysplasia until bone metastasis, but the SPARC plasma level was as low as that of normal women, in contrast to patients that never develop bone metastasis, suggesting that circulating SPARC was counter adhesive. Altogether, the early identification of SPARC/Endothelin 1/ET_AR in dysplastic lesions would be important to devise therapies preventing metastasis engraftment, since often carcinoma cells spread to distant organs at the time or even before patients present with cancer.     

Generation of Rho Zero Cells: Visualization and Quantification of the mtDNA Depletion Process

Human mitochondrial DNA (mtDNA) is located in discrete DNA-protein complexes, so called nucleoids. These structures can be easily visualized in living cells by utilizing the fluorescent stain PicoGreen^®. In contrary, cells devoid of endogenous mitochondrial genomes (ρ⁰ cells) display no mitochondrial staining in the cytoplasm. A modified restriction enzyme can be targeted to mitochondria to cleave the mtDNA molecules in more than two fragments, thereby activating endogenous nucleases. By applying this novel enzymatic approach to generate mtDNA-depleted cells the destruction of mitochondrial nucleoids in cultured cells could be detected in a time course. It is clear from these experiments that mtDNA-depleted cells can be seen as early as 48 h post-transfection using the depletion system. To prove that mtDNA is degraded during this process, mtDNA of transfected cells was quantified by real-time PCR. A significant decline could be observed 24 h post-transfection. Combination of both results showed that mtDNA of transfected cells is completely degraded and, therefore, ρ⁰ cells were generated within 48 h. Thus, the application of a mitochondrially-targeted restriction endonuclease proves to be a first and fast, but essential step towards a therapy for mtDNA disorders.     

Konformation und Rotationsbarrieren substituierter Glyoxylsäureamide

Conformation and Rotation Barriers of Substituted Glyoxylic Acid Amides Semiempirical calculations predict an orthogonal orientation of the carbonyl groups in tertiary glyoxylic acid amides, which is in good agreement with an X-ray structure analysis of 5 . Due to the influence of the α-carbonyl group, the rotation barrier in the substituted glyoxylic acid amides 2a–d, 3a, 3b , and 4–6 (ΔG^#_c = 84–92 kJ mol⁻¹) is about 10 kJ/mol higher than in simple acid amides, as was found by dynamic NMR line shape analysis.     

Mechanical response of novel SiOC glasses to high temperature exposition

The presented work describes mechanical properties of materials prepared by the pyrolysis of polysiloxane resins. The polymeric precursors have different chemical composition. Materials under investigation are predetermined for high temperature resistant applications usually in composite form, i.e. accompanied by some reinforcement. Instrumented hardness tests were employed for material characterisation. The Vickers hardness, Martens hardness and indentation elastic modulus were the key parameters, determined either from the standard optical technique or load–indentation depth curves. The influence of mechanical properties on the monomers ratio was established. The exposition to the temperature between 1200 °C and 1500 °C in air was applied to observe damage caused by these severe conditions.     

Nanodiamond-mediated crystallization in fibers of PANI nanocomposites produced by template-free polymerization: Conductive and thermal properties of the fibrillar networks

The detonation nanodiamond is a novel versatile nanomaterial with tunable properties and surface chemistry. In this work, we report on a template-free method to synthesize polyaniline based nanocomposite fibers during a chemical oxidative precipitation polymerization where the cooperative interactions between nanodiamond and polyaniline nucleates trigger the final morphology of the nanocomposite. FE–SEM and TEM observations evidence the prominent growth of fibril-like structures assembled in 2-D networks of tightly woven, partially oriented fibers. Optical and Raman spectroscopy and X-ray diffraction analyses reveal that the polymer chains are in a protonated emeraldine form and organize themselves in a highly ordered 3-D spatial arrangement. Conductivity measurements performed on isolated fibers by a conductive tip of an AFM apparatus highlight that the diamond filler does not affect the conductive properties of the polyaniline matrix while increases the thermal stability of the polymer as confirmed by TGA studies.     

Lignin from Annual Plants as Raw Material Source for Flavors and Basic Chemicals

The enzymatic conversion of lignins, possibly in combination with electrochemical oxidation, makes aromatics such as syringol, guaiacol, vanillin and catechol available in the qualities required by the fragrance industry. The lignins were obtained by soda digestion from wheat straw and Miscanthus, characterized and then converted with laccases. The overall yield amounted up to 9 wt % with a product spectrum confined to four substances. Catechol was the major product, with a fraction of ≈75 %. It can easily be isolated by extraction with acetone.     

Inhibition of the FGF/FGFR System Induces Apoptosis in Lung Cancer Cells via c-Myc Downregulation and Oxidative Stress

Lung cancer represents an extremely diffused neoplastic disorder with different histological/molecular features. Among the different lung tumors, non-small-cell lung cancer (NSCLC) is the most represented histotype, characterized by various molecular markers, including the expression/overexpression of the fibroblast growth factor receptor-1 (FGFR1). Thus, FGF/FGFR blockade by tyrosine kinase inhibitors (TKi) or FGF-ligand inhibitors may represent a promising therapeutic approach in lung cancers. In this study we demonstrate the potential therapeutic benefit of targeting the FGF/FGFR system in FGF-dependent lung tumor cells using FGF trapping (NSC12) or TKi (erdafitinib) approaches. The results show that inhibition of FGF/FGFR by NSC12 or erdafitinib induces apoptosis in FGF-dependent human squamous cell carcinoma NCI-H1581 and NCI-H520 cells. Induction of oxidative stress is the main mechanism responsible for the therapeutic/pro-apoptotic effect exerted by both NSC12 and erdafitinib, with apoptosis being abolished by antioxidant treatments. Finally, reduction of c-Myc protein levels appears to strictly determine the onset of oxidative stress and the therapeutic response to FGF/FGFR inhibition, indicating c-Myc as a key downstream effector of FGF/FGFR signaling in FGF-dependent lung cancers.