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Extending on recent progress in control of matter at the nanoscale, functional nanoparticles and drug nanocarriers are being actively developed with the promise of improved delivery of therapeutic agents. Nanotechnology-enabled drug delivery approaches usually aim at reducing the systemic distribution and associated side-effects typically observed with conventional chemotherapeutic molecules as well as increasing the therapeutic index of the active agents. The enhanced permeation and retention effect has been exploited with notable success to passively deliver nanostructured drug carriers and therapeutic nanoparticles in vivo. Strategies aimed at further enhancing the nanocarriers accumulation within tumor tissues are under intensive investigation and could enable, in a not too distant future, the realization of the long sought after goal of chemotherapy without - or with reduced - side-effects. In particular, immunotargeted approaches are widely predicted to offer much greater specificity towards the target cells and tissues. Advancement in molecular biology has indeed made a wealth of information available in biological processes and application of this new knowledge to nanostructured agents, has also generated unprecedented hope of novel molecular diagnostic and therapeutic strategies. Focusing on oncological applications, this review aims to discuss the recent developments in immunotargeting of functional nanoparticles and drug nanocarriers and the integration of these systems into clinically relevant therapeutic applications. Refereed/Peer-reviewed

Towards an integrated multifunctional nanocarrier, core–shell nanostructures have been developed using the electrostatic self-assembly of an organic shell onto magnetic nanoparticles. Refereed/Peer-reviewed

Introduction: Antibodies covalently conjugated with chelators such as 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) are required for radioimmunoscintigraphy and radioimmunotherapy, which are of growing importance in cancer medicine. Method: Here, we report a suite of simple methods that provide a preclinical assessment package for evaluating the effects of DOTA conjugation on the in vitro and in vivo performance of monoclonal antibodies. We exemplify the use of these methods by investigating the effects of DOTA conjugation on the biochemical properties of the DAB4 clone of the La/SSB-specific murine monoclonal autoantibody, APOMAB®, which is a novel malignant cell death ligand. Results: We have developed a 96-well microtiter-plate assay to measure directly the concentration of DOTA and other chelators in antibody-chelator conjugate solutions. Coupled with a commercial assay for measuring protein concentration, the dual microtiter-plate method can rapidly determine chelator/antibody ratios in the same plate. The biochemical properties of DAB4 immunoconjugates were altered as the DOTA/Ab ratio increased so that: (i) mass/charge ratio decreased; (ii) hydrodynamic radius increased; (iii) antibody immunoactivity decreased; (iv) rate of chelation of metal ions and specific radioactivity both increased and in vivo, (v) tumor uptake decreased as nonspecific uptake by liver and spleen increased. Conclusion: This simplified suite of methods readily identifies biochemical characteristics of the DOTA-immunoconjugates such as hydrodynamic diameter and decreased mass/charge ratio associated with compromised immunotargeting efficiency and, thus, may prove useful for optimizing conjugation procedures in order to maximize immunoconjugate-mediated radioimmunoscintigraphy and radioimmunotherapy.

Towards a robust and universal functionalization procedure with alkanethiols for gold nanorods and plasmonic nanoparticles, a straightforward two-step approach is described. Refereed/Peer-reviewed

Biomimetic coatings offer exciting options to modulate the biocompatibility of biomaterials. The challenge is to create surfaces that undergo specific interactions with cells without promoting nonspecific fouling. This work reports an innovative approach toward biomimetic surfaces based on the covalent immobilization of a carboxylate terminated PEGylated hyaluronan (HA-PEG) onto plasma functionalized NiTi alloy surfaces. The metal substrates were aminated via two different plasma functionalization processes. Hyaluronan, a natural glycosaminoglycan and the major constituent of the extracellular matrix, was grafted to the substrates by reaction of the surface amines with the carboxylic acid terminated PEG spacer using carbodiimide chemistry. The surface modification was monitored at each step by X-ray photoelectron spectroscopy (XPS). HA-immobilized surfaces displayed increased hydrophilicity and reduced fouling, compared to bare surfaces, when exposed to human platelets (PLT) in an in vitro assay with radiolabeled platelets (204.1 +/- 123.8 x 10 (3) PLT/cm (2) vs 538.5 +/- 100.5 x 10 (3) PLT/cm (2) for bare metal, p0.05). Using a robust plasma patterning technique, microstructured hyaluronan surfaces were successfully created as demonstrated by XPS chemical imaging. The bioactive surfaces described present unique features, which result from the synergy between the intrinsic biological properties of hyaluronan and the chemical composition and morphology of the polymer layer immobilized on a metal surface.

A critical requirement toward the clinical use of nanocarriers in drug delivery applications is the development of optimal biointerfacial engineering procedures designed to resist biologically nonspecific adsorption events. Minimization of opsonization increases blood residence time and improves the ability to target solid tumors. We report the electrostatic self-assembly of polyethyleneimine−polyethylene glycol (PEI-PEG) copolymers onto porous silica nanoparticles. PEI-PEG copolymers were synthesized and their adsorption by self-assembly onto silica surfaces were investigated to achieve a better understanding of structure−activity relationships. Quartz-crystal microbalance (QCM) study confirmed the rapid and stable adsorption of the copolymers onto silica-coated QCM sensors driven by strong electrostatic interactions. XPS and FT-IR spectroscopy were used to analyze the coated surfaces, which indicated the presence of dense PEG layers on the silica nanoparticles. Dynamic light scattering was used to optimize the coating procedure. Monodisperse dispersions of the PEGylated nanoparticles were obtained in high yields and the thin PEG layers provided excellent colloidal stability. In vitro protein adsorption tests using 5% serum demonstrated the ability of the self-assembled copolymer layers to resist biologically nonspecific fouling and to prevent aggregation of the nanoparticles in physiological environments. These results demonstrate that the electrostatic self-assembly of PEG copolymers onto silica nanoparticles used as drug nanocarriers is a robust and efficient procedure, providing excellent control of their biointerfacial properties. Refereed/Peer-reviewed

A novel plasma functionalization process based on the pulsed plasma polymerization of allyl glycidyl ether is reported for the generation of robust and highly reactive epoxy-functionalized surfaces with well-defined chemical properties. Using a multitechnique approach including X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), infrared spectroscopy (FT-IR), atomic force microscopy (AFM) and ellipsometry, the effect of the plasma deposition parameters on the creation and retention of epoxy surface functionalities was characterized systematically. Under optimal plasma polymerization conditions (duty cycle: 1 ms/20 ms and 1 ms/200 ms), reactive uniform films with a high level of reproducibility were prepared and successfully used to covalently immobilize the model protein lysozyme. Surface derivatization was also carried out with ethanolamine to probe for epoxy groups. The ethanolamine blocked surface resisted nonspecific adsorption of lysozyme. Lysozyme immobilization was also done via microcontact printing. These results show that allyl glycidyl ether plasma polymer layers are an attractive strategy to produce a reactive epoxy functionalized surface on a wide range of substrate materials for biochip and other biotechnology applications. Refereed/Peer-reviewed

Nanotechnology has generated tremendous hopes in recent years toward the design of advanced functional materials, especially in the bio-medical field. Nano-sized-materials such as magnetite nanoparticles display indeed fascinating physico-chemical properties that, if tuned properly, can be exploited to design new bio-diagnostic and therapeutic strategies as well as innovative biotechnology methodologies. Owing to their biocompatibility and excellent magnetic properties, magnetite nanocrystals have been the object of a tremendous amount of research in the last decade and numerous (bio)applications have been reported. Importantly, advances in the synthesis of magnetite nanoparticles enable excellent control over their size, shape, and composition. Despite these remarkable progresses, many issues remain to be overcome for these nanotechnology products to revolution the medical practice. The fine control and application of colloidal nanostructures such as magnetite nanoparticles in complex biological systems ...

We report the design of a platform for the delivery of hydrophobic drugs via a macromolecular prodrug approach combined with LbL-assembled polyelectrolyte multilayers. A hyaluronan ester prodrug of the chemotherapeutic drug paclitaxel has been synthesized. Conjugation of the drug to hyaluronan through a labile succinate ester did not inhibit its activity. Using quartz crystal microbalance, atomic force microscopy, and UV spectroscopy, we have shown that the presence of the hydrophobic paclitaxel moieties does not prohibit the layer-by-layer construction of the multilayers. Release of the drug from the paclitaxel-loaded multilayers upon hydrolysis of the ester linkage resulted in a drastic cell death. Application of this delivery platform to substrates such as colloids, biomedical implants, or vascular tissues may lead to new therapeutic strategies.

This work was partly supported by the Natural Science and Engineering Research Council (NSERC) of Canada. More than a million metallic endovascular devices are implanted each year, but the quest for the perfect material continues. The importance of interfacial properties in the overall biocompatibility of metals and alloys has been recognized for a long time. In particular, these properties modulate the hemocompatibility of devices in contact with blood and, in turn, strongly influence implantation outcomes. In this article, the relative properties of metallic materials commonly used in endovascular applications are reviewed. Particular emphasis is given to the corrosion behavior of metallic endovascular materials and the specific surface treatments used in the production processes. Issues relative to corrosion assays will also be reviewed in terms of their relevance to in vivo applications. The potential adverse effects of degradation products with respect to endovascular applications will be described. Finally, this review addresses future perspectives of metallic devices in endovascular procedures in view of the recent promises of antiproliferative strategies that are likely to profoundly modify current procedures.

Catheter-based brachytherapy is one of the most effective modalities to inhibit hyperplasia following revascularization procedures. Radioactive stents have failed, however, to prevent clinical hyperplasia due to excessive late lumen loss on the edge of the devices. Numerous strategies have been proposed to circumvent the drawbacks of irradiation therapies, such as the use of more appropriate radionuclides or the "hot-end" stents approach. This paper describes versatile radioactive devices obtained by coating plasma functionalized surfaces-stents or catheters-with a hyaluronan (HA)-diethylenetriamine pentaacetic acid (DTPA) conjugate (HA-DTPA) complexed with a gamma or beta radionuclide. Yttrium and indium were used as radionuclide models, due to their suitability for endovascular radiotherapy. X-ray photoelectron microscopy and time-of-flight secondary ions mass spectrometry analyses confirmed the successful immobilization of the HA-DTPA conjugate on both the metallic (NiTi) and polymeric (Teflon) plasma functionalized surfaces. HA-DTPA-coated surfaces were significantly more hydrophilic than bare surfaces (39.5 degrees vs. 67 degrees on NiTi substrate and 29 degrees vs. 128 degrees on Teflon substrate). Therapeutic doses of yttrium and indium were easily loaded onto the surfaces and remained stable over 2 weeks with a radionuclide loss of about 6%. The HA-DTPA-coated Teflon surfaces presented significantly less fibrinogen adsorption than uncoated materials in an in vitro flow model. This approach, which combines the hemocompatibility of HA-coated surfaces and the anti-proliferative effects of an appropriate radiotherapy, constitutes a promising methodology to alleviate the restenosis induced by existing devices.

Functional silicon nanowires (SiNWs) are promising building blocks in the design of highly sensitive photodetectors and bio-chemical sensors. We systematically investigate the photoresponse properties of ultrathin SiNWs (20 nm) fabricated using a size-reduction method based on e-beam lithography and tetramethylammonium hydroxide wet-etching. The high-quality SiNWs were able to detect light from the UV to the visible range with excellent sensitivity (∼1 pW/array), good time response, and high photoresponsivity (R ∼ 2.5 x 10⁴A/W). Improvement of the ultrathin SiNWs' photoresponse has been observed in comparison to 40 nm counter-part nanowires. These properties are attributable to the predominance surface-effect due to the high surface-to-volume ratio of ultrathin SiNWs. Long-term measurements at different temperatures in both the forward and reverse bias directions demonstrated the stability and reliability of the fabricated device. By sensitizing the fabricated SiNW arrays with cadmium telluride quantum dots (QDs), hybrid QD SiNW devices displayed an improvement in photocurrent response under UV light, while preserving their performance in the visible light range. The fast, stable, and high photoresponse of these hybrid nanostructures is promising towards the development of optoelectronic and photovoltaic devices. Refereed/Peer-reviewed

The objectives of this study were to establish an in-depth understanding of the signals induced by mammalian cells in surface plasmon resonance (SPR) sensing. To this end, two plasmonic structures with different propagation and penetration distances were used: conventional surface plasmon resonance and long-range surface plasmon resonance. Long-range SPR showed a lesser sensitivity to the absolute number of round cells but a greater resolution due to its very narrow spectral dip. The effect of cell spreading was also investigated and the resonance angle of long-range SPR was mostly insensitive unlike in the conventional SPR counterpart. Experimental data was compared with suitable models used in the SPR literature. Although these simple averaging models could be used to describe some of the experimental data, important deviations were observed which could be related to the fact that they do not take into consideration critical parameters such as plasmon scattering losses, which is particularly crucial in the case of long-range SPR structures. The comparison between conventional and long-range SPR for cellular schemes revealed important fundamental differences in their responses to the presence of cells, opening new horizons for SPR-based cell assays. From this study, long-range SPR is expected to be more sensitive towards both the detection of intracellular events resulting from biological stimulation and the detection of microorganisms captured from complex biological samples.

Background: Staphylococcus aureus in its biofilm form has been associated with recalcitrant chronic rhinosinusitis with significant resistance to conventional therapies. This study aims to determine if liposomal-encapsulation of a precursor ofthe naturally occurring antimicrobial nitric oxide (NO) enhances its desired anti-biofilm effects against S. aureus, in the hope that improving its efficacy can provide an effective topical agent for future clinical use. Methodology: S. aureus ATCC 25923 biofilms were grown in-vitro using the Minimum Biofilm Eradication Concentration(MBEC) device and exposed to 3 and 60 mg/mL of the NO donor isosorbide mononitrate (ISMN) encapsulated into different anionic liposomal formulations based on particle size (unilamellar ULV, multilamellar MLV) and lipid content (5 and 25 mM) at 24 h and 5 min exposure times. Biofilms were viewed using Live-Dead Baclight stain and confocal scanning laser microscopy and quantified using the software COMSTAT2. Results: At 3 and 60 mg/mL, ISMN-ULV liposomes had comparable and significant anti-biofilm effects compared to untreated control at 24 h exposure (p = 0.012 and 0.02 respectively). ULV blanks also had significant anti-biofilm effects at both 24 h and 5 min exposure (p = 0.02 and 0.047 respectively). At 5 min exposure, 60 mg/mL ISMN-MLV liposomes appeared to have greater anti-biofilm effects compared to pure ISMN or ULV particles. Increasing liposomal lipid content improved the anti-biofilm efficacy of both MLV and ULVs at 5 min exposure. Conclusion: Liposome-encapsulated ‘‘nitric oxide’’ is highly effective in eradicating S. aureus biofilms in-vitro, giving great promise for use in the clinical setting to treat this burdensome infection. Further studies however are needed to assess its safety and efficacy in-vivo before clinical translation is attempted. Refereed/Peer-reviewed

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Nickel-titanium (NiTi) alloy derives its biocompatibility and good corrosion resistance from a homogeneous oxide layer mainly composed of TiO(2), with a very low concentration of nickel. In this article, we described the corrosion behavior of NiTi alloys after mechanical polishing, electropolishing, and sterilization processes using cyclic polarization and atomic absorption. As a preparative surface treatment, electropolishing decreased the amount of nickel on the surface and remarkably improved the corrosion behavior of the alloy by increasing the mean breakdown potential value and the reproducibility of the results (0.99 +/- 0.05 V/SCE vs. 0.53 +/- 0. 42). Ethylene oxide and Sterrad(R) sterilization techniques did not modify the corrosion resistance of electropolished NiTi, whereas a steam autoclave and, to a lesser extent, peracetic acid sterilization produced scattered breakdown potential. In comparing the corrosion resistance of common biomaterials, NiTi ranked between 316L stainless steel and Ti6A14V even after sterilization. Electropolished NiTi and 316L stainless-steel alloys released similar amounts of nickel after a few days of immersion in Hank's solution. Measurements by atomic absorption have shown that the amount of released nickel from passive dissolution was below the expected toxic level in the human body. Auger electron spectroscopy analyses indicated surface contamination by Ca and P on NiTi during immersion, but no significant modification in oxide thickness was observed.

Based on promising reports from international randomized trials such as BENESTENT, vascular stent implantation has been increasingly used - with more than 500,000 implantations per year worldwide - and has become a procedure of choice in the treatment of atherosclerotic vascular disease [1,2]. Since the first implantation in 1986, many devices, mostly balloon expandable stainless steel stents, have been approved by regulatory agencies, for both peripheral and coronary revascularization. In the early 90’s, many studies have reported experimental temporary or permanent use of NiTi stents [3,4]. Due to the thermoelastic properties of the alloy, optimal deployment of NiTi self expanding stents can be easily achieved with high expansion ratio and less longitudinal shortening than most common stainless steel devices. In addition, their flexibility and radiopacity along with their good biocompatibility and resistance to corrosion have contributed to their increasing use in cardiovascular applications [5-7]. Despite its good biocompatibility, like all metallic materials NiTi is prone to adsorption of plasma protein such as fibrinogen, which is a potent promoter of platelet adhesion [8]. In a recent study, Makkar et al. have shown that surface topography significantly affects the thrombogenicity of NiTi stents, which may in turn have an effect on complications observed much after implantation [9]. Indeed, platelets adhesion is the first step of thrombus formation which may lead to acute and sub-acute thrombosis. Stent thrombosis still represents a major complication after stent implantation, especially for small vessels, thrombus containing lesions and bifurcation stenoses [10]. Moreover, through the release of growth factor by activated platelets, thrombus formation is expected to participate to the restenosis process initiation [11]. Many strategies have been developed to reduce stents thrombogenicity such as improvement of surface characteristics or coating with pharmacological drugs and polymers [9,12,13].

Sterilization is required for using any device in contact with the human body. Numerous authors have studied device properties after sterilization and reported on bulk and surface modifications of many materials after processing. These surface modifications may in turn influence device biocompatibility. Still, data are missing on the effect of sterilization procedures on new biomaterials such as nickel-titanium (NiTi). Herein we report on the effect of dry heat, steam autoclaving, ethylene oxide, peracetic acid, and plasma-based sterilization techniques on the surface properties of NiTi. After processing electropolished NiTi disks with these techniques, surface analyses were performed by Auger electron spectroscopy (AES), atomic force microscopy (AFM), and contact angle measurements. AES analyses revealed a higher Ni concentration (6-7 vs. 1%) and a slightly thicker oxide layer on the surface for heat and ethylene oxide processed materials. Studies of surface topography by AFM showed up to a threefold increase of the surface roughness when disks were dry heat sterilized. An increase of the surface energy of up to 100% was calculated for plasma treated surfaces. Our results point out that some surface modifications are induced by sterilization procedures. Further work is required to assess the effect of these modifications on biocompatibility, and to determine the most appropriate methods to sterilize NiTi.

As a potential biomaterial for many medical applications, NiTi alloy derives its good biocompatibility and corrosion resistance from a homogeneous and protective oxide layer, mainly composed of TiO2, with little concentration of nickel. However, during corrosion testing at high potential, NiTi is susceptible to pitting corrosion, which may affect the amount of ions (nickel and titanium) released by the alloy and thus, may affect its biocompatibility. As a passivating treatment, electropolishing (EP) was demonstrated to decrease the amount of nickel on the surface and to remarkably improve the corrosion behavior of the alloy. After sterilization by ethylene oxide (EO), no modification of the promising corrosion behavior of electropolished NiTi were observed, although some surface modifications were reported. The corrosion resistance of ethylene oxide sterilized and electropolished samples ranked between that of the commonly used Ti6A14V and 316L (0.4 less than 1 less than 1.4 mV/SCE) implant alloys.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The deposition of polysaccharide-based self-assembled nanocoatings onto damaged arteries is described as a means not only to protect a damaged artery against thrombogenesis, but also to control the healing processes by incorporating biologically active components within the multilayer. As shown by confocal microscopy, the polysaccharide multilayer was retained on the artery in physiological condition and prevented platelet adhesion. Diffusion of the polysaccharides within the artery was also observed and may be used to efficiently target the vascular wall. The NO-precursor l-arginine was used a drug model and incorporated within the self-assembled layers.

In order to achieve a high density of grafted PEG chains on functional nanoparticles, a 2-step method is proposed that enables the tethering of the PEG chains under theta solvency conditions while preserving their colloidal stability. UV-vis studies were first used to determine the phase transition temperature of PEG chains grafted onto gold nanoparticles, which corresponded to the loss of the colloidal stability of the nanoparticles. In the first step of the process, PEG chains were tethered under good solvency conditions (×1 PBS and room temperature), which avoided problems with colloidal stability. In the second step, the solvent was changed to ×1 PBS supplemented with 0.4 M K2SO4 and the temperature of the solution was raised to 50 °C which was found to correspond to the onset of collapse of the tethered PEG chains. Model studies performed on planar gold surfaces using QCM and XPS showed that the proposed 2-step procedure resulted in a significantly increased density of grafted PEG chains. When applying the process to gold nanoparticles using either PEG-NHS ester or PEG-SH, it was observed that the initial PEG layer obtained in the first step of the process efficiently protected the colloidal nanoparticle suspension from aggregation during the second PEGylation step performed under theta solvency conditions. The dense PEG graft layers created by the 2-step method drastically reduced the non-specific fouling by proteins in vitro and were readily amenable to functionalization by biological ligands. Herceptin antibody was used to target the human breast cancer cell line SK-BR-3. A high extent of binding of nanoparticles to cells was observed, whereas control PEGylated nanoparticles without Herceptin did not bind to cells. The specificity of binding was further confirmed by a competitive binding assay using added free Herceptin in solution. Thus, the proposed procedure using two subsequent additions of PEG chains below and above the phase transition condition can be used to prepare dense PEG layers on solid nanoparticles with a high degree of bio-inertness and immune-specificity. Refereed/Peer-reviewed

Des les annees 1980 s’epanouissent en France les premiers usages grand public de l’informatique et de la communication interactive dans un contexte socio-technique marque par la telematique et « l’informatique familiale ». Des groupes d’early adopters passionnes et une part non negligeable de novices enthousiastes decouvrent la micro-informatique et le Minitel. Des sociabilites complexes se mettent alors en place grâce a des vecteurs nombreux qui permettent de faire circuler et partager savoir-faire et imaginaires collectifs (revues, fanzines, messageries, clubs et associations). Le passage d’une culture informaticienne a l’âge numerique marque par le grand public est enclenche.Ce creuset initial des pratiques et des representations se developpe sur la base d’usages specifiques (pratique du basic, premiers traitements de texte, messageries) et concourt a enraciner une « culture de l’ecran interactif » qui se reinvente avec Internet quinze ans plus tard en donnant a voir un exemple significatif de continuite dans les usages par-dela les ruptures technologiques.

Building on recent breakthroughs in the field of microfluidic-based capture of rare cancer cells circulating in the blood, the present article reports on the use of Herceptin functionalized PDMS devices designed to efficiently capture from blood cancer cells, overexpressing the tyrosine kinase human epidermal growth factor receptor HER2. The identification of patients overexpressing HER2 is critical as it typically associates with an aggressive disease course in breast cancer and poor prognosis. Importantly, HER2 positive patients have been found to significantly benefit from Herceptin Trastuzumab, a humanized monoclonal antibody MAb against HER2. Disposable PDMS devices prepared using standard soft lithography were functionalized by the plasma polymerization of an epoxy-containing monomer. The epoxy-rich thin film AGEpp thus created could be conjugated with Herceptin either directly or through a polyethylene glycol interlayer. The properties and reactivity toward the monoclonal antibody conjugation of these coatings were determined using x-ray photoelectron spectroscopy; direct conjugation provided a good compromise in reactivity and resistance to biologically nonspecific fouling and was selected. Using the breast cancer cell line SKBR3 as a model for cells overexpressing HER2, the immunocapture efficacy of the Herceptin functionalized PDMS was demonstrated in model studies. Validation studies confirmed the ability of the device to efficiently capture 80 capture yield HER2 positive cells from full blood. Refereed/Peer-reviewed

In this study, robust antibacterial coatings were created on stainless steel through the covalent grafting of antibacterial peptides onto an organic-polymeric interlayer deposited by RF-glow discharge plasma. X-Ray photoelectron spectroscopy was used to characterize and optimize the two steps of the coating process. The biocidal activity of these surfaces was demonstrated against both Gram+ and Gram− bacteria using ISO tests. 3 to 6 log10 reductions of both Gram+ and Gram− bacterial strains were obtained compared to uncoated stainless steel and depending on the particular antibacterial peptide immobilized. Importantly the antibacterial surfaces were resistant to several cleaning conditions. The latter is significant as the stability of such antibacterial surfaces in close to real life conditions is a major concern and leaching, de-lamination, rearrangement and ageing of the coating can lead to insufficient long term biofilm resistance of the surface. Refereed/Peer-reviewed

A l’occasion du projet d’informatisation du controle aerien civil qui debute en 1961, une equipe de psychologues est associee aux ingenieurs charges de la realisation du nouveau systeme pour l’adapter aux conditions particulieres du travail des « aiguilleurs du ciel ». Cette collaboration permet a l’ergonomie de l’informatique de forger ses premiers concepts et de les appliquer au Cautra (Coordination automatique du trafic aerien). Heberges des 1969 par l’Institut de recherche en informatique et en automatique (Inria), l’equipe d’Andre Bisseret decouvre les difficultes du travail transdisciplinaire avec une communaute informaticienne se defiant de cette irruption incomprehensible de psychologues sur son territoire de competence. Ces conflits, incomprehensions et rencontres manquees n’empechent pas l’ergonomie de developper ses recherches autour des notions d’utilisateur et d’interface et de proposer des reponses aux interrogations et aux angoisses que l’ordinateur fait naitre dans le grand public des le milieu des annees 1970.

Monocrystalline iron oxide nanoparticles were synthesised by a one-pot procedure using iron salts in benzyl alcohol and functionalised with dopamine and carboxylmethylated dextran. Dextran macromolecules with low and high carboxyl contents were synthesised and grafted onto the dopamine-functionalised nanoparticles. The particles were characterised using X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), transmission electron microscopy (TEM) and dynamic light scattering (DLS). Monodisperse functionalised nanoparticles were obtained with a hydrodynamic diameter of 20?50 nm. The functionalisation also provided excellent colloidal stability in phosphate buffered saline, even at high salt concentration.

Comment l’institution museale dans son ensemble et dans sa diversite a-t-elle negocie le virage numerique des annees 1990-2000 et comment s’adapte-t-elle aujourd’hui aux nouveaux usages (reseaux sociaux, Web 2.0…) de ces outils numeriques ? Les reponses apportees ici a ces interrogations montrent la diversite des situations et ne permettent pas de degager un modele bien defini par des musees qui, dans ce domaine, semblent encore assez marques par l’experimentation et le pragmatisme.

En dialogue avec les principaux fondements de l’épistémologie historique, cet article examine les enjeux, les attentes et les pratiques que suscite l’irruption des archives du web dans le champ de l’histoire du temps présent. Entre nouveauté des matériaux, héritage disciplinaire et continuité des méthodes, il s’agit de comprendre les redéfinitions à venir du rôle de l’historien. In dialogue with the main theoretical foundations of historical epistemology, this article examines the issues, the expectations and the practices created by the sudden appearance of the archives of the web in the sphere of contemporary history. Between new materials, the heritage of the subject and the continuity of methods, it is a question of understanding the future redefinitions of the role of the historian.

This article, focusing on France, explores the notion of a “Web of professionals” and seeks to establish its factual, epistemological, and methodological implications for the history of the World Wide Web in the 1990s. This research reflects on the promises of the New Economy and the roles of the various controversies, cultures, imaginaries, and forms of mediation affecting the business world in its appropriation of the Web. It also aims to reappraise the individual and collective stakeholders whose active part has been somehow underestimated or obscured by the image of the mass Internet user. The professionalization of Web activities, the development of a new generation of entrepreneurs and the conversion of business models to online practices are all significant parts of the emergent Web culture in France, as well as factors contributing to this emergence.

In April 1904, the well-known French actress Ms. Sylviac had her phone service suspended by the telephone administration after being accused of insulting the demoiselles du telephone – France’s then exclusively female staff of phone operators, who failed to connect her to the number she requested. The major newspapers (Le Matin, Le Temps, etc.) quickly transformed Ms. Sylviac into a symbol of helpless subscribers forced to turn the other cheek before an all-powerful, monopoly-abusing administration. The real question became whether telephone operators should be considered officials receiving special protections in cases of job-related insults. Beyond the actress’s personal situation, the case highlighted the new balance of power being established between subscribers, the telephone administration and its employees.

L'enseignement de la traite négrière et de l'esclavage peut se traiter en trois séances : les premiers empires coloniaux, le commerce triangulaire, puis l'exploitation des esclaves. L'évaluation sommative répond aux trois compétences d’Éduscol : savoir que la conquête européenne entraîne la constitution de premiers empires coloniaux et la traite d’esclaves transatlantique, reconnaître sur une carte les principaux empires coloniaux et retrouver le trajet d’un esclave et décrire sa vie sur une plantation. Il peut être difficile d'élaborer un récit historique sur ce sujet en évitant de choquer les élèves. En effet, l'affect peut prendre davantage de place que l'enseignement. Il est essentiel de préparer cette séquence en questionnant la sensibilité des élèves, leur compréhension des débats sur les sources. De plus, il faut garder à l'esprit l'idée permanente de tri des documents : les razzias, la traversée à bord des négriers, les sévices peuvent être abordés par des documents adaptés.