Biological tolerance of different materials in bulk and nanoparticulate form in a rat model: sarcoma development by nanoparticles.

In order to study the pathobiological impact of the nanometre-scale of materials, we evaluated the effects of five different materials as nanoparticulate biomaterials in comparison with bulk samples in contact with living tissues. Five groups out of 10 rats were implanted bilaterally for up to 12 months with materials of the same type, namely TiO2, SiO2, Ni, Co and polyvinyl chloride (PVC), subcutaneously with bulk material on one side of the vertebral column and intramuscularly with nanoparticulate material on the contralateral side. At the end of each implantation time, the site was macroscopically examined, followed by histological processing according to standard techniques. Malignant mesenchymal tumours (pleomorphic sarcomas) were obtained in five out of six cases of implanted Co nanoparticle sites, while a preneoplastic lesion was observed in an animal implanted with Co in bulk form. In the Ni group, all animals rapidly developed visible nodules at the implanted sites between 4 and 6 months, which were diagnosed as rhabdomyosarcomas. Since the ratio of surface area to volume did not show significant differences between the Ni/Co group and the TiO2/SiO2/PVC group, we suggested that the induction of neoplasia was not mediated by physical effects, but was mediated by the well-known carcinogenic impact of Ni and Co. The data from the Co group show that the physical properties (particulate versus bulk form) could have a significant influence on the acceleration of the neoplastic process.     

The Target Differential Game with Two Defenders

A cooperative aircraft differential game where an Attacker missile pursues an unmanned aerial vehicle (UAV) herein called the Target is addressed. The Target UAV cooperates with up to two Defender missiles which are launched in order to intercept the Attacker before the latter reaches the Target. This is a scenario with important military applications where each one of the agents is an autonomous air vehicle. Each agent plans and corrects its course of action in order to defeat an opposing force while simultaneously optimizing an operational relevant cost/payoff performance measure. The Target and the Defenders cooperate to form a team against the Attacker. The results in this paper build on the solution of a three agent differential game, where the three players are the Target, the Attacker, and one Defender; in this paper, the benefits of firing a second Defender are considered. Indeed, launching two interceptor missiles is a standard procedure by providing redundant backup. Building on the solution of the one-Defender problem, it is possible to address a seemingly intractable problem, where the Target needs to decide which Defender(s) to cooperate with, in addition to obtaining the optimal headings of every player in the game. Given the initial positions of the players, we solve the problem of determining if a second Defender improves the Target/Defender(s) payoff and provide the optimal strategies for each of the agents involved. Finally, we address the game of kind (for the case of one Defender) which provides the safety regions to determine which side will win based on the initial state. These safety regions provides the Target’s area of vulnerability, and using these results, we describe the reduction to the Target’s vulnerability area brought by an additional Defender.     

On the impact of the choice of model VOC in the evaluation of V-based catalysts for the total oxidation of dioxins: Furan vs. chlorobenzene

V-based catalysts, widely developed for the catalytic abatement of dioxins, are usually studied and optimized by investigating the oxidation of model chlorinated aromatic compounds (e.g. chlorobenzene). Even though the oxygenated function included in the central aromatic ring of the molecular structure of a dioxin could influence major aspects of the catalytic process, it has never been taken into account in the reported works. In this study, furan is chosen as a model for the central oxygenated ring of a polychlorinated dibenzo furan (PCDF) and its oxidation is compared to the case of chlorobenzene. The strategy was to check systematically if the improvements of formulations enlightened from our previous investigation on chlorobenzene also remain beneficial with furan. It turned out that the use of a sulfate containing TiO₂ as support for the active VO_x phase as well as the doping of the formulation with Mo or W oxides had very different impacts in the two cases. Some improvement strategies prove to be inefficient or deleterious in the case of furan. Competition tests further suggest that the adsorption behavior of dioxin could be better imitated by furan than by chlorobenzene. These observations highlight, in the case for which working with the target pollutant is difficult (as with dioxins), that the choice of the model molecule is critical.     

Nanometer range: A new theoretical challenge for microelectronics and optoelectronics

The equation is identified, from a couple of odd percussions, which yields the pilot wave forming the aura of a particle in the space conjugate to the four-dimensional space of direct experience. This leads to a substitute of the Copenhagen Interpretation providing the frame for demonstrating Heisenberg's uncertainty principle through a theorem of Fourier analysis. Revisiting the method of space-time domain paves the way to a new era of developments, by considering that a trapped particle located in a bounded bi-dimensional space, having less than 1 eV of kinetic energy, should have an associated wavelength representing a fraction of a wave cycle. In order to face the challenge, a new optoelectronics concept is proposed to contend with the broadening of the frequency bandwidth for a particle-wave trapped in a single-electron box: quasi-virtual electrons, trapped in nanometric single-electron thin boxes, interact by absorption-emission processes with coherent electromagnetic radiations. The migration is proposed for nanoelectronic transistor fabrication from semiconductor to semi-refractor materials.     

Influence of test protocol in determining the blood response to model polymers

A multi-parametric, multi-center evaluation of three polymers was performed measuring their response to blood contact. The purpose of this study was to pinpoint differences in tests performed for assessing basic hemocompatibility on identical materials at different centers and attempt to rationalize. Assays for platelet adhesion, activation, aggregability and activation of the coagulation system in addition to an ex vivo patency assay were performed at four centers across Europe, using protocols favored by each center for determining the blood-contacting performance of a biomaterial. Three polymers were chosen for their expected blood response spanning the range of undesirable to desirable: ethylenevinylacetate (EVA), polyvinylchloride (PVC) and PVC modified with polyethylene oxide (PEO). The assays were ranked in terms of their efficacy compared to cost and simplicity. A correlation between assays was calculated, indicating the ability of one test to correctly determine the blood response compared to another. Some assays were unable to distinguish between materials, but of the assays which could, the materials were ranked in the following order: EVA; PVC; PVC-PEO, EVA producing the most undesirable response. It is concluded that many commonly used assays for determining hemocompatibility are inappropriate, but there are simple and reliable test methods available which correlate well with the more sophisticated protocols.     

Equlibrium between Liquid Fe‐Ti‐O Slags and Metallic Iron

The compositions of Fe‐Ti‐O melts in equilibrium with molten iron have been determined by melting mixtures of TiO₂, metallic iron and various additions of either Fe₂O₃ or metallic titanium in a high‐frequency induction furnace. The furnace had a vertically segmented water‐cooled copper crucible which enabled the mixture to be melted with vigorous stirring inside a freeze‐lining of about 1 mm thickness. The slag compositions were found to form a curved line in the ternary diagram FeTiO₃ – TiO₂ – Ti₂O₃ with its highest TiO₂ content slightly higher than the pseudobrookite (M₃O₅) composition FeTi₂O₅ ‐ Ti₃O₅. The slags were examined by X‐ray diffraction and microprobe analyses. For all slags the main phase was pseudobrookite (M₃O₅) solid solution with some rutile or Magnéli phase (Ti_nO_2n‐1). The most iron‐rich and the most titanium‐rich slags contained also some FeTiO₃, respectively Ti₂O₃ phase. A melting point diagram is suggested with a eutectic groove running between the M₃O₅ phase and the TiO₂ or Magnéli phase from about 1665°C for the iron‐free to the less than 1500°C for the titanium‐free slags.     

Multiplexed Biosensing Diagnostic Platforms Detecting Autoantibodies to Tumor-Associated Antigens from Exosomes Released by CRC Cells and Tissue Samples Showed High Diagnostic Ability for Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer-related death worldwide. The five-year survival rate of CRC patients depends on the stage at diagnosis, being higher than 80% when CRC is diagnosed in the early stages but lower than 10% when CRC is diagnosed in advanced stages. Autoantibodies against specific CRC autoantigens (tumor-associated antigens (TAAs)) in the sera of patients have been widely demonstrated to aid in early diagnosis. Thus, we herein aim to identify autoantigens target of autoantibodies specific to CRC that possess a significant ability to discriminate between CRC patients and healthy individuals by means of liquid biopsy. To that end, we examined the protein content of the exosomes released by five CRC cell lines and tissue samples from CRC patients by means of immunoprecipitation coupled with mass spectrometry analysis. A total of 103 proteins were identified as potential autoantigens specific to CRC. After bioinformatics and meta-analysis, we selected 15 proteins that are more likely to be actual CRC autoantigens in order to evaluate their role in CRC prognosis by Western blot (WB) and immunohistochemistry (IHC). We found dysregulation at the protein level for 11 of these proteins in both tissue and plasma exosome samples from patients, along with an association of nine of these proteins with CRC prognosis. After validation, all but one showed a statistically significant high diagnostic ability to distinguish CRC patients and individuals with premalignant lesions from healthy individuals, either by luminescence Halotag-based beads, or by a multiplexed biosensing platform involving the use of magnetic microcarriers as solid support modified with covalently immobilized Halotag fusion proteins constructed for CRC detection. Taken together, our results highlight the usefulness of the approach defined here to identify the TAAs specific to chronic diseases; they also demonstrate that the measurement of autoantibody levels in plasma against the TAAs identified here could be integrated into a point-of-care (POC) device for CRC detection with high diagnostic ability.     

Electro-Fenton and photoelectro-Fenton degradations of the drug beta-blocker propranolol using a Pt anode: identification and evolution of oxidation products

The beta-blocker propranolol hydrochloride has been degraded by electrochemical advanced oxidation processes like electro-Fenton (EF) and photoelectro-Fenton (PEF) using a single cell with a Pt anode and an air diffusion cathode (ADE) for H(2)O(2) electrogeneration and a combined system containing the above Pt/ADE pair coupled in parallel to a Pt/carbon-felt (CF) cell. Organics are mainly oxidized with hydroxyl radical (OH) formed from Fenton's reaction between added Fe(2+) and electrogenerated H(2)O(2). The PEF treatment in Pt/ADE-Pt/CF system yields almost total mineralization because OH production is enhanced by Fe(2+) regeneration from Fe(3+) reduction at the CF cathode and Fe(III) complexes with generated carboxylic acids are rapidly photodecarboxylated under UVA irradiation. Lower mineralization degree is found for PEF in Pt/ADE cell due to the little influence of UVA light on Fe(2+) regeneration. The homologous EF processes are much less potent as a result of the persistence of Fe(III)-carboxylate complexes. Aromatic intermediates such as 1-naphthol, 1,4-naphthoquinone and phthalic acid and generated carboxylic acids such as pyruvic, glycolic, malonic, maleic, oxamic, oxalic and formic are identified. While chloride ion remains stable, NH(4)(+) and NO(3)(-) ions are released to the medium. A reaction sequence for propranolol hydrochloride mineralization is proposed.     

Fluorescence in situ hybridization for detection of classical propionibacteria with specific 16S rRNA-targeted probes and its application to enumeration in Gruyère cheese

The classical or dairy propionibacteria have well-documented industrial applications and have been proposed for probiotic applications. Given their industrial importance it is necessary to employ fast and reliable techniques to monitor the growth during products elaboration, industrial fermentations or the intestinal transit. Therefore, the aim of this investigation was to design oligonucleotide probes targeting the 16S rRNA of dairy propionibacteria and optimise the fluorescence in situ hybridization (FISH) protocol to detect these bacteria. Two specific probes were in silico designed to detect Propionibacterium freudenreichii and P. jensenii, named Pfr435 and Pj446 respectively. The FISH protocol was optimised for the hybridisation of propionibacteria cells with the universal probe Eub338 and the designed probes. These probes were assayed in situ for their specificity to hybridise species of propionibacteria by observation using fluorescence microscopy and results were compared with the probe Pap446 previously designed for P. acidipropionici. Probes Pap446, Pfr435 and Pj446 were also evaluated by fluorescence spectrophotometry to assess the influence of cells physiological state during growth in batch culture in the fluorescence intensity. The maximum fluorescence intensity was observed at the onset of the stationary phase of growth and was then reduced. However, changes on the cells permeability did not reduce the efficiency of 16S rRNA hybridisation with the fluorescence-labelled probes. Propionibacteria counts obtained by FISH and plate count methods were compared in a commercial Gruyère cheese. The results showed that this method can be used as a rapid technique for the enumeration of these bacteria in cheese samples.     

Prediction of hydrodynamic behaviour in bubble columns

A simple theoretical model is used to describe hydrodynamic behaviour in bubble columns. The model is based on an energy balance which takes into account the energy dissipation in the liquid motion and the energy dissipation at the gas–liquid interface. Gas hold-up, liquid velocity at the column axis and radial profile of liquid velocity are predicted in a wide range of operating conditions (J_G up to 1·452 m s⁻¹) and column sizes (D = 0·1–1 m and H = 1·22–9·5 m) with good accuracy. Predictions of liquid velocity are also compared with one of the most widely accepted models.