Detection of irrigation inhomogeneities in an olive grove using the NDRE vegetation index obtained from UAV images

We have developed a simple photogrammetric method to identify heterogeneous areas of irrigated olive groves and vineyard crops using a commercial multispectral camera mounted on an unmanned aerial vehicle (UAV). By comparing NDVI, GNDVI, SAVI, and NDRE vegetation indices, we find that the latter shows irrigation irregularities in an olive grove not discernible with the other indices. This may render the NDRE as particularly useful to identify growth inhomogeneities in crops. Given the fact that few satellite detectors are sensible in the red-edge (RE) band and none with the spatial resolution offered by UAVs, this finding has the potential of turning UAVs into a local farmer’s favourite aid tool.Peer ReviewedPostprint (published version

Effect of surface modification on the stability of oxide scales formed on TiAl intermetallic alloys at high temperature

TiAl intermetallic alloys have many interesting potential application in the automitive and aerospace industry due to their low density and good mechanical properties. Unfortunately they have a low oxidation resistance at temperature higher than 700 °C and the improvement of their oxidation behavior is still an open issue. In this work the surface of a TiAlCrNB alloy has been modified by means of their anodic coating or cerium converison coating. Afterwards the stability of the oxide scale formed at 900 °C has been studied by analyzing crack formation and porpagatin, which is the phenomenon that con produce scale spallation during the alloy cooling

Antitumor effect of oncolytic virus and paclitaxel encapsulated in extracellular vesicles for lung cancer treatment

Standard of care for cancer is commonly a combination of surgery with radiotherapy or chemoradiotherapy. However, in some advanced cancer patients this approach might still remaininefficient and may cause many side effects, including severe complications and even death. Oncolytic viruses exhibit different anti-cancer mechanisms compared with conventional therapies, allowing the possibility for improved effect in cancer therapy. Chemotherapeutics combined with oncolytic viruses exhibit stronger cytotoxic responses and oncolysis. Here, we have investigated the systemic delivery of the oncolytic adenovirus and paclitaxel encapsulated in extracellular vesicles (EV) formulation that, in vitro, significantly increased the transduction ratio and the infectious titer when compared with the virus and paclitaxel alone. We demonstrated that the obtained EV formulation reduced the in vivo tumor growth in animal xenograft model of human lung cancer. Indeed, we found that combined treatment of oncolytic adenovirus and paclitaxel encapsulated in EV has enhanced anticancer effects both in vitro and in vivo in lung cancer models. Transcriptomic comparison carried out on the explanted xenografts from the different treatment groups revealed that only 5.3% of the differentially expressed genes were overlapping indicating that a de novo genetic program is triggered by the presence of the encapsulated paclitaxel: this novel genetic program might be responsible of the observed enhanced antitumor effect. Our work provides a promising approach combining anticancer drugs and viral therapies by intravenous EV delivery as a strategy for the lung cancer treatment.Peer reviewe

FLIM reveals alternative EV-mediated cellular up-take pathways of paclitaxel

In response to physiological and artificial stimuli, cells generate nano-scale extracellular vesicles (EVs) by encapsulating biomolecules in plasma membrane-derived phospholipid envelopes. These vesicles are released to bodily fluids, hence acting as powerful endogenous mediators in intercellular signaling. EVs provide a compelling alternative for biomarker discovery and targeted drug delivery, but their kinetics and dynamics while interacting with living cells are poorly understood. Here we introduce a novel method, fluorescence lifetime imaging microscopy (FLIM) to investigate these interaction attributes. By FLIM, we show distinct cellular uptake mechanisms of different EV subtypes, exosomes and microvesicles, loaded with anti-cancer agent, paclitaxel. We demonstrate differences in intracellular behavior and drug release profiles of paclitaxel-containing EVs. Exosomes seem to deliver the drug mostly by endocytosis while microvesicles enter the cells by both endocytosis and fusion with cell membrane. This research offers a new real-time method to investigate EV kinetics with living cells, and it is a potential advancement to complement the existing techniques. The findings of this study improve the current knowledge in exploiting EVs as next-generation targeted drug delivery systems.Peer reviewe

A Sliding Mode Multimodel Control for a Sensorless Photovoltaic System

In this work we will talk about a new control test using the sliding mode control with a nonlinear sliding mode observer, which are very solicited in tracking problems, for a sensorless photovoltaic panel. In this case, the panel system will has as a set point the sun position at every second during the day for a period of five years; then the tracker, using sliding mode multimodel controller and a sliding mode observer, will track these positions to make the sunrays orthogonal to the photovoltaic cell that produces more energy. After sunset, the tracker goes back to the initial position (which of sunrise). Experimental measurements show that this autonomic dual axis Sun Tracker increases the power production by over 40%

Multivariable discrete time repetitive control system.

International audienceThis paper deals with an iterative learning control law for multivariable systems. The desired inputs are supposed to be known and periodic. The principle of the control is to make outputs as close as possible to desired inputs at each new period. After the design of multivariable repetitive controller, we give the stability condition of the algorithm and some simulation results

Proton translocation in proteins

The active transport of protons across the low dielectric barrier imposed by biological membranes is accomplished by a plethora of proteins that span the ca. 40 Å of the phospholipid bilayer. The free energy derived from the proton electrochemical potential established by the translocation of these protons can subsequently be used to drive vital chemical reactions of the cell, such as ATP synthesis and cell locomotion. Membrane-bound proton translocating proteins have now been found for a variety of organisms and tissues (1). The driving force for proton pumping in these proteins is supplied by numerous mechanisms, including light absorption (e.g. bacteriorhodopsin) (2a,b), ligand binding (e.g. ATPase) (3), and electrochemistry (e.g. electron transfer through cytochrome c oxidase) (4). Thus nature has devised a variety of methods for supplying the energy required for proton pumping by these proteins. Such diversity notwithstanding, the proteins most likely share some common elements of structure and mechanism that allow them to function as proton pumps. A number of theoretical mechanisms have been put forth for both general proton translocation (5-7) and for energy coupling in specific proton pumps. However, despite almost three decades of intensive research, the details of the mechanism(s) and structural requirements for proton pumping remain largely unresolved. To some extent this is the result of the paucity of structural information available for integral membrane proteins. This situation may soon improve as a result of advances in protein methodologies that have allowed several integral membrane proteins to be successfully crystalized (8), and the increased use of genetic engineering to obtain recombinant proton translocating proteins that will offer an opportunity to assess the importance of specific amino acids for the proton translocation process (9)

Geometric and Reflectance Signature Characterization of Complex Canopies Using Hyperspectral Stereoscopic Images from Uav and Terrestrial Platforms

Peer reviewe

Reactive oxygen species induced structural alterations of substance P

Substance P (SP1-11) was exposed to a continuous flux of superoxide ( O 2 - ) or hydroxyl radicals (.OH) in a hypoxanthine (HX)/xanthine oxidase (86 mU) system in the presence of 1 mM deferoxamine and 40 mM D-mannitol or 50 μM FeCI3. 6H2O and 50 μM EDTA, respectively. O 2 - caused fragmentation between the Phe7 and Phe8, whereas .OH induced cleavage also between the Phe8 and Gly9. Reactive oxygen species H2O2 and HCIO did not cause fragmentation, but modification of the amino acid side chains and/or aggregation with altered hydrophobicity in reverse phase high performance liquid chromatography compared to native SP1-11. Furthermore, exposure of SP1-11 to phorbol myristate acetate preactivated neutrophils resuited in products similar to those observed upon exposure to superoxide or hydroxyl radicals in a cell-free HX/xanthine oxidase system. This study suggests that, in contrast to rigid proteins, fragmentation is relatively easily induced in a small peptide like SP1-11, perhaps due to strain on the peptide and t-carbon bonds caused by the movable, random coil configuration acquired by SP1-11 in an aqueous solution. Oxidative modification might modulate paracrine actions of SP1-11 at site of inflammation