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The Golgi complex (GC) is the main station along the cell biosecretory pathway. Until now, mechanisms of intra-Golgi transport (IGT) have remained unclear. Herein, we confirm that the goodness-of-fit of the regression lines describing the exit of a cargo from the Golgi zone (GZ) corresponds to an exponential decay. When the GC was empty before the re-initiation of the intra-Golgi transport, this parameter of the curves describing the kinetics of different cargoes (which are deleted in Golgi vesicles) with different diffusional mobilities within the GZ as well as their exit from the GZ was maximal for the piecewise nonlinear regression, wherein the first segment was horizontal, while the second segment was similar to the exponential decay. The kinetic curve describing cargo exit from the GC per se resembled a linear decay. The Monte-Carlo simulation revealed that such curves reflect the role of microtubule growth in cells with a central GC or the random hovering of ministacks in cells lacking a microtubule. The synchronization of cargo exit from the GC already filled with a cargo using the wave synchronization protocol did not reveal the equilibration of cargo within a Golgi stack, which would be expected from the diffusion model (DM) of IGT. Moreover, not all cisternae are connected to each other in mini-stacks that are transporting membrane proteins. Finally, the kinetics of post-Golgi carriers and the important role of SNAREs for IGT at different level of IGT also argue against the DM of IGT. [ABSTRACT FROM AUTHOR]

This paper focuses on the preparation of chitosan-based nanofibers embedding copper oxide nanoparticles to create multifunctional materials that meet the demands of contemporary applications. To this end, a mixture of chitosan, quaternized chitosan and poly (ethylene glycol) was used as polymeric matrix, considering their own contribution to the final material's properties and their ability to stabilize the copper oxide nanoparticles. An exhaustive investigation of the nanofibers was done in order to assess their composition and morphology (FTIR, 1H NMR, WXRD, TGA, SEM, TEM, POM, UV–vis) and to study their mechanical, antimicrobial and antioxidant properties, air and water permeability and ability for air filtration. It was shown that the copper oxide nanoparticles were anchored into the polymeric matrix via strong hydrogen bonding and electrostatic interactions, which induced the improvement of the mechanical properties and antioxidant activity. The copper oxide nanoparticles favored the thinning of the fibers during electrospinning process and improved the antibacterial activity and dust filtration capacity. Besides, the fibers displayed air permeability and vapor water transmission rate similar to synthetic nanofibers, while being biodegradable. All these performances recommend the new materials for developing antibacterial eco-materials with good breathability to be used as hygienic textiles, masks, or air filters. [Display omitted] Chitosan nanofibers encapsulating copper oxide nanoparticles by needleless electrospinning High antioxidant and antimicrobial activity Tunable air permeability, vapor water transmission rate and dedusting ability High mechanical properties and soil biodegradability [ABSTRACT FROM AUTHOR]

The aim of the paper was to investigate the ability of an eco-friendly luminescent xerogel prepared by chitosan crosslinking with a phenothiazine luminogen to detect and remove heavy metals. Its ability to give a divergent morphological and optical response towards fifteen environmental relevant metals was investigated by naked eye and UV lamp, fluorescence spectroscopy and scanning electron microscopy. A distinct response was noted for mercury, consisting in the transformation of the xerogel into a rubber-like material accompanied by the red shifting of the color of emitted light from yellow-green to greenish-yellow domain. The particularities of the metals anchoring into the xerogel were analyzed by FTIR spectroscopy and X-ray diffraction. The morphological changes and the metal uptake were analyzed by SEM-EDAX, swelling and gravimetric methods. It was concluded that mercury has a superior affinity towards this heteroatoms rich system, leading to a secondary crosslinking. This directed a great absorption capacity of 1673 mg/g and a specific morphological response for mercury ion concentrations up to 0.001 ppm. • A luminescent organic xerogel was investigated for heavy metal detection and removal. • The xerogel showed a distinct morphological behavior towards mercury ions. • This was sensible and selective over a large series of environment relevant metals. • This was attributed to a secondary morphology due to a supplementary crosslinking. [ABSTRACT FROM AUTHOR]

The paper focuses on the preparation of phenothiazine based nanoparticles, both in liquid and solid states, by reprecipitation in water and solvent induced phase separation respectively. Polymethylmethacrylate was used as an inert matrix and polyfluorene as a luminescent matrix. The morphological features of the nanoparticles were investigated by dynamic light scattering, and SEM, AFM and POM microscopy, which revealed their supramolecular ordering as nanocrystals. Their photophysical behaviour was monitored by UV–vis and photoluminescence spectroscopy. The nanocrystals emitted green light, with higher efficiency compared to the bulk crystals, reaching an absolute quantum yield of 35% in water, 45% in polymethylmethacrylate, and 39% in polyfluorene. [ABSTRACT FROM AUTHOR]

A series of poly(azomethine-phenothiazine)s was synthesized by using the reaction of 10-methyl-phenothiazine-3,7-dicarbaldehyde with diamines containing fluorene chromophore or polyethylene glycol (PEG) flexible spacer. The polymers were structurally characterized by 1 H NMR and FTIR spectral techniques, elemental analysis and wide angle X-ray diffraction. Their thermal properties were monitored by using variable temperature polarized light microscopy whilst their photophysical behaviour was demonstrated by using UV–vis absorption and photoluminescence spectroscopy. All of these polymers were found to emit green light with high quantum yield, in both solution and solid state. The emission efficiency in solid state was further improved by mixing the fluorene containing polymers with the PEG containing one, when continuous films with quantum efficiency of up to 16% were obtained. [ABSTRACT FROM AUTHOR]

A series of nine dyes based on electron-donating phenothiazine core functionalized with various carbonyl containing electron-withdrawing moieties as primary end group and with or without bromine as a second heavy end group were designed and synthesized to generate variable supramolecular architectures with distinct thermotropic, photophysical, and electrochemical properties. The supramolecular architecture of the obtained dyes was studied in detail by single crystal X-ray diffraction and polarized light microscopy, while optoelectronic properties were investigated by UV-vis and photoluminescence spectroscopy and cyclic voltammetry measurements. The phenothiazine dyes emit light from UV to orange domain, depending on the electron-withdrawing substituent, with great quantum yield reaching up to 71% and high color purity. The introduction of the bromine as a second substituent produced a nearly 2-fold increase of the quantum yield, compared with their counterparts. It was settled that this major benefit of the bromine on the improvement of the quantum yield happened because by its presence some molecular orbital interactions were generated. An interesting and challenging achievement was evidenced in the case of the direct connection of the formyl group to the phenothiazine ring when an unexpected planarization of the dye, unknown up to now in the literature, with drastic consequences on the photophysical and electrochemical behavior was attained. It was concluded that there is a close relationship between the nature of the building blocks of the phenothiazine dyes and their ability to promote favorable properties for different optoelectronic applications. [ABSTRACT FROM AUTHOR]

Transpired solar air collectors are cost-benefit optimized systems, increasingly used nowadays to heat or to preheat the fresh air needed inside buildings. The most important issue regarding the implementation of solar collectors is determined by the fact that these systems can be used only when solar radiation is available because of their lack of thermal mass. Phase changing materials (PCM) are widely studied in the recent years in different applications given their capacity of storing large quantities of latent thermal energy. The aim of the present paper is to study through an experimental approach, an innovative, enhanced transpired air solar collector with integrated PCM which has the benefit to increase its operating period and its overall efficiency. The data achieved experimentally shows that, by implementing RT35 organic PCM (paraffin) within a real scale solar collector, the maximum increase in temperature will be higher by 8.8% while its coefficient of performance will by 10.6% higher. Moreover, the useful operating time (when the coefficient of performance has values above 1) of the solar collector without PCM is 434 min, while in the case of the collector with PCM it is 937 min, resulting in a longer operation period of 110% (∼8 h more). Furthermore, the average coefficient of performance of the solar collector without embedded PCM is 6.6, while the average coefficient of performance of the solar collector with embedded PCM is 7.3 (10.6% higher). The main conclusion of the current study is that the innovative approach of PCM integration within solar air collectors can increase the overall efficiency of the system, the number of operating hours and even the temperature difference between ambient and exhaust air. [ABSTRACT FROM AUTHOR]

A mixture of polymeric complexes based on the reaction between Re(CO)5Cl and the porous polymeric network coming from the coupling of melamine and benzene-1,3,5-tricarboxaldehyde was obtained and characterized by FTIR, NMR, SEM, XPS, ICP, XRD, and cyclic voltammetry (CV). The formed rhenium-based porous hybrid material reveals a noticeable capability of CO2 absorption. The gas absorption amount measured at 295 K was close to 44 cm3/g at 1 atm. An interesting catalytic activity for CO2 reduction reaction (CO2RR) is observed, resulting in a turn over-number (TON) close to 6.3 under 80 min of test at −1.8 V vs. Ag/AgCl in a TBAPF6 0.1 M ACN solution. A possible use as filler in membranes or columns can be envisaged. [ABSTRACT FROM AUTHOR]

A series of binary phenothiazine based co-crystals were designed with the aim to reach materials with improved quantum efficiency in solid state. To this end, a host dibromine functionalized phenothiazine was mixed with a guest formyl based phenothiazine in various molar ratios, from 1:1 up to 1:9, to form single crystals and thin films as well. Single crystal X-ray diffraction, polarized light microscopy, 1H NMR and FTIR spectroscopies indicated the successful formation of supramolecular synthons via halogen bonds. Polarized light microscopy and atomic force microscopy indicated the formation of submicrometric crystals into the co-crystal films. The photophysical behaviour was investigated by UV–vis and photoluminescence spectroscopies, and showed a remarkable improvement of the quantum yield, reaching values of 27% for single co-crystals and of 42% for thin films of nano-co-crystals. Image 1 • Co-crystals were prepared from isostructural phenothiazine derivatives. • Halogen bonds were evidenced as driving forces of co-crystalization. • The quantum efficiency increased from 2% to 27% for single co-crystals and of 42% for thin films of nano co-crystals. [ABSTRACT FROM AUTHOR]