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International audience; Passive plasmonic metasurfaces enable image multiplexing by displaying different images when altering the conditions of observation. Under white light, three-image multiplexing with polarization selective switching has been recently demonstrated using femtosecond-laser-processed random plasmonic metasurfaces. Here, the implementation of image multiplexing is extended, thanks to a color search algorithm, to various observation modes compatible with naked-eye observation under incoherent white light and to four-image multiplexing under polarized light. The laser-processed random plasmonic metasurfaces enabling image multiplexing exhibit self-organized patterns that can diffract light or induce dichroism through hybridization between the localized surface plasmon resonance of metallic nanoparticles and a lattice resonance. Improved spatial resolution makes the image quality compatible with commercial use in secured documents, as well as the processing time and cost thanks to the use of a nanosecond laser. This high speed and flexible laser process, based on energy efficient nanoparticle reshaping and self-organization, produces centimeter-scale customized tamper-proof images at low cost, which can serve as overt security features.

The basic understanding of the biological effects of eukaryotic translation initiation factors (EIFs) remains incomplete, notably for their roles independent of protein translation. Different EIFs exhibit nuclear localization and DNA-related functions have been proposed, but the understanding of EIFs novel functions beyond protein translation lacks of integrative analyses between the genomic and the proteomic levels. Here, the noncanonical function of EIF3F was studied in human lung adenocarcinoma by combining methods that revealed both the protein–protein and the protein–DNA interactions of this factor. We discovered that EIF3F promotes cell metastasis in vivo. The underpinning molecular mechanisms involved the regulation of a cluster of 34 metastasis-promoting genes including Snail2, as revealed by proteomics combined with immuno-affinity purification of EIF3F and ChIP-seq/Q-PCR analyses. The interaction between EIF3F and signal transducer and activator of transcription 3 (STAT3) controlled the EIF3F-mediated increase in Snail2 expression and cellular invasion, which were specifically abrogated using the STAT3 inhibitor Nifuroxazide or knockdown approaches. Furthermore, EIF3F overexpression reprogrammed energy metabolism through the activation of AMP-activated protein kinase and the stimulation of oxidative phosphorylation. Our findings demonstrate the role of EIF3F in the molecular control of cell migration, invasion, bioenergetics, and metastasis. The discovery of a role for EIF3F–STAT3 interaction in the genetic control of cell migration and metastasis in human lung adenocarcinoma could lead to the development of diagnosis and therapeutic strategies.

Mitochondria are dynamic cellular organelles responsible for a large variety of biochemical processes as energy transduction, REDOX signaling, the biosynthesis of hormones and vitamins, inflammation or cell death execution. Cell biology studies established that 1158 human genes encode proteins localized to mitochondria, as registered in MITOCARTA. Clinical studies showed that a large number of these mitochondrial proteins can be altered in expression and function through genetic, epigenetic or biochemical mechanisms including the interaction with environmental toxics or iatrogenic medicine. As a result, pathogenic mitochondrial genetic and functional defects participate to the onset and the progression of a growing number of rare diseases. In this review we provide an exhaustive survey of the biochemical, genetic and clinical studies that demonstrated the implication of mitochondrial dysfunction in human rare diseases. We discuss the striking diversity of the symptoms caused by mitochondrial dysfunction and the strategies proposed for mitochondrial therapy, including a survey of ongoing clinical trials.

The quality of procedural analgesia and sedation among trauma patients has not been studied much in the prehospital setting. The main objective of this study was to characterize the quality of procedural analgesia sedation practices in prehospital settings in trauma patients.This was an open-label observational prospective multicenter study (January 01, 2012-December 31, 2013). We included all consecutive trauma victims undergoing a potentially painful procedure on the accident scene. The primary endpoint was the procedural pain intensity.Data for 210 patients aged 11 to 98 years were analyzed. The most common lesions were limb fractures or dislocations. The most common procedures were limb realignment and splinting. Overall, 25 different drug combinations [with paracetamol [acetaminophen], non-steroidal anti-inflammatory drugs, nefopam, opioids, loco-regional anesthesia, Equimolar Mixture of Oxygen/Nitrous Oxide (EMONO), sedative drugs] were used by the emergency medical services (EMS). One hundred seventeen patients (55%) received either one or two sedative drugs (among ketamine, propofol, and midazolam), 171 patients (81%) received morphine that was combined with a sedative drug in 54% of cases. During the procedure, 95 patients, 45% [95% Confidence Interval (CI) 39-52] experienced intense to severe pain. Among patients who received sedative drugs, 27% (32/117) had intense to severe pain vs. 68% (63/93) in patients who did not, that is, 40% difference [95% CI 33.8-47.0]. Seventeen patients (8%) experienced 18 adverse events of which 6 were respiratory adverse events. A deep sedation occurred in 17 patients. No center had any specific protocols for procedural sedation analgesia.Procedural sedation-analgesia was inadequate in almost half of the trauma patients in the out-of-hospital setting. The reasons of these failures were probably multiple. The non-administration of a sedative drug despite an indication or non-adapted doses, in the context of a lack of specific protocols, was certainly one of them.

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International audience

Cystic fibrosis (CF) is a systemic genetic disease that leads to pulmonary and digestive disorders. In the majority of CF patients, the intestine is the site of chronic inflammation and microbiota disturbances. The link between gut inflammation and microbiota dysbiosis is still poorly understood. The main objective of this study was to assess gut microbiota composition in CF children depending on their intestinal inflammation. We collected fecal samples from 20 children with CF. Fecal calprotectin levels were measured and fecal microbiota was analyzed by 16S rRNA sequencing. We observed intestinal inflammation was associated with microbiota disturbances characterized mainly by increased abundances of Staphylococcus, Streptococcus, and Veillonella dispar, along with decreased abundances of Bacteroides, Bifidobacterium adolescentis, and Faecalibacterium prausnitzii. Those changes exhibited similarities with that of Crohn&rsquo, s disease (CD), as evidenced by the elevated CD Microbial-Dysbiosis index that we applied for the first time in CF. Furthermore, the significant over-representation of Streptococcus in children with intestinal inflammation appears to be specific to CF and raises the issue of gut&ndash, lung axis involvement. Taken together, our results provide new arguments to link gut microbiota and intestinal inflammation in CF and suggest the key role of the gut&ndash, lung axis in the CF evolution.

In 2016 France hosted the European football championship. In a context of an increased terrorist threat, Chemical, Bacteriological, Radiological, Nuclear (CBRN) attacks were considered possible. Three days prior to the beginning of the event, the Health Authorities required that a medium sized hospital close to a major potential target, prepare a chemical decontamination centre. Despite a low level of preparedness, little external help, and very few extra resources, an efficient decontamination chain (all premises necessary for the management of contaminated victims: from the entrance gate to the post-decontamination dressing cabins) was set up in 15 days (12 days after the unrealistic deadline). Numerous practical measures allowed three persons in CBRN personal protective equipment (PPE) to manage the whole chain, providing a maximum flow of 24 persons/hour. Volunteers were trained in PPE dressing, undressing and in decontamination procedures. This experience, offers a novel paradigm in managing chemical decontamination, in terms of attitude, and with adaptations to overcome practical constraints. It demonstrates that it is possible to set up a decontamination chain rapidly at very low cost. This provides an attractive option for less advanced countries and in humanitarian contexts. Some additional refinements, enhancements may be considered to further improve results. (Disaster Med Public Health Preparedness. 2018;12:649–656)

Spondyloarthritis (SpA) pathophysiology remains largely unknown. While the association with genetic factors has been established for decades, the influence of gut microbiota is only an emerging direction of research. Despite the remarkable efficacy of anti-TNF-α treatments, non-responders are frequent and no predictive factors of patient outcome have been identified. Our objective was to investigate the modifications of intestinal microbiota composition in patients suffering from SpA three months after an anti-TNF-α treatment. We performed 16S rDNA sequencing of 38 stool samples from 19 spondyloarthritis patients before and three months after anti-TNF-α treatment onset. SpA activity was assessed at each time using ASDAS and BASDAI scores. Some modifications of the microbiota composition were observed after three months of anti-TNF-α treatment, but no specific taxon was modified, whatever the clinical response. We identified a particular taxonomic node before anti-TNF-α treatment that can predict the clinical response as a biomarker, with a higher proportion of Burkholderiales order in future responder patients. This study suggests a cross-influence between anti-TNF-α treatment and intestinal microbiota. If its results are confirmed on larger groups of patients, it may pave the way to the development of predictive tests suitable for clinical practices.

Objective Autosomal recessive spastic ataxia of Charlevoix–Saguenay (ARSACS) is caused by mutations in the SACS gene. SACS encodes sacsin, a protein whose function remains unknown, despite the description of numerous protein domains and the recent focus on its potential role in the regulation of mitochondrial physiology. This study aimed to identify new mutations in a large population of ataxic patients and to functionally analyze their cellular effects in the mitochondrial compartment. Methods A total of 321 index patients with spastic ataxia selected from the SPATAX network were analyzed by direct sequencing of the SACS gene, and 156 patients from the ATAXIC project presenting with congenital ataxia were investigated either by targeted or whole exome sequencing. For functional analyses, primary cultures of fibroblasts were obtained from 11 patients carrying either mono- or biallelic variants, including 1 case harboring a large deletion encompassing the entire SACS gene. Results We identified biallelic SACS variants in 33 patients from SPATAX, and in 5 nonprogressive ataxia patients from ATAXIC. Moreover, a drastic and recurrent alteration of the mitochondrial network was observed in 10 of the 11 patients tested. Interpretation Our results permit extension of the clinical and mutational spectrum of ARSACS patients. Moreover, we suggest that the observed mitochondrial network anomalies could be used as a trait biomarker for the diagnosis of ARSACS when SACS molecular results are difficult to interpret (ie, missense variants and heterozygous truncating variant). Based on our findings, we propose new diagnostic definitions for ARSACS using clinical, genetic, and cellular criteria. Ann Neurol 2015;78:871–886

Au cours des dernières années, plusieurs pratiques culturelles et artistiques observées à Montréal remettent en question l’utilisation de la dichotomie classique d’espaces publics-privés. Pour pallier ce manque conceptuel, nous proposons, dans le cadre de cet article, de préciser la notion d’espaces équivoques. Par la présentation sommaire de cinq exemples de la région de Montréal, nous offrirons un aperçu des formes que peuvent prendre ces espaces. Puis, à partir d’une double étude de cas réalisée entre 2009 et 2011, nous démontrerons par quels processus le caractère équivoque de certains espaces émerge, s’accentue ou s’amenuise. Les résultats de cette recherche à caractère exploratoire permettront de fournir de nouveaux éclairages quant aux définitions d’espace public et privé et de soulever certaines pistes de réflexion quant aux relations qu’entretiennent les individus avec l’environnement urbain., In the last few years, several cultural and artistic practices observed in Montreal have challenged the usage of the traditional dichotomy of public and private spaces. In response to this conceptual concern we purpose to define in this article the notion of equivocal spaces. By briefly examining five examples in the region of Montreal we will demonstrate a few of the forms these spaces can take. In addition, by a double case study completed between 2009 and 2011, we aim to establish the process by which the equivocal character emerges, is maintained, grows and diminishes. We believe the results of this exploratory research will provide new light in terms of the definition of public and private spaces and provide several lines of inquiry with respect to the relationship that individuals have with the urban environment.

A process of creating controlled silver nanostructures using atomic force microscope technique is reported. The nanostructures are grown on both the silica surface and silica–indium-tin-oxide interface of a silver salt impregnated mesoporous silica film, deposited on indium tin oxide coated glass substrate. Voltage is applied between a conductive atomic force microscope tip and the indium tin oxide substrate to create the silver nanostructures. The possibility of switching the positions of the nanostructures between the silica film surface and the film–indium-tin-oxide interface, by reversing the electrical polarity of the tip, is demonstrated. It is also shown that the conductive channels can be created through the silica layer provided that the created metallic nanostructures are large enough to grow inside the film volume from one side to the other. The electrical conductivity of the film can be locally changed in a reversible manner by applying successively negative and positive voltages to the tip.

Mycoplasma meleagridis and Mycoplasma gallinarum are bacteria that affect birds, but little is known about the genetic basis of their interaction with chickens and other poultry. Here, we sequenced the genomes of M. meleagridis strain MM_26B8_IPT and M. gallinarum strain Mgn_IPT, both isolated from chickens showing respiratory symptoms, poor growth, reduction in hatchability, and loss of production.

International audience; This paper describes a fast and one-step technique to grow single gold filaments at the apex of commercial conductive AFM tips. It is implemented with an atomic force microscope in air with a high relative humidity at room temperature and is based on a bias-assisted electro-reduction of gold ions directly at the tip apex. The technique requires only ad hoc substrates made of a mesoporous silica layer loaded with gold salt deposited on a conductive electrode. It leads to the growth, at the tip apex, of filaments whose length can be monitored and controlled during the growth between tens and hundreds of nanometers and whose radius of curvature can be as low as 3 nm. Made of polycrystalline gold nanostructures, the filaments are chemically and mechanically stable and conductive.

International audience; The rapid Arab-Islamic conquest during the early Middle Ages led to major political and cultural changes in the Mediterranean world. Although the early medieval Muslim presence in the Iberian Peninsula is now well documented, based in the evaluation of archeological and historical sources, the Muslim expansion in the area north of the Pyrenees has only been documented so far through textual sources or rare archaeological data. Our study provides the first archaeo-anthropological testimony of the Muslim establishment in South of France through the multidisciplinary analysis of three graves excavated at Nimes. First, we argue in favor of burials that followed Islamic rites and then note the presence of a community practicing Muslim traditions in Nimes. Second, the radiometric dates obtained from all three human skeletons (between the 7th and the 9th centuries AD) echo historical sources documenting an early Muslim presence in southern Gaul (i.e., the first half of 8th century AD). Finally, palaeogenomic analyses conducted on the human remains provide arguments in favor of a North African ancestry of the three individuals, at least considering the paternal lineages. Given all of these data, we propose that the skeletons from the Nimes burials belonged to Berbers integrated into the Umayyad army during the Arab expansion in North Africa. Our discovery not only discusses the first anthropological and genetic data concerning the Muslim occupation of the Visigothic territory of Septimania but also highlights the complexity of the relationship between the two communities during this period.

To evaluate the diagnostic performance of a portable semi-quantitative whole blood immunoassay measuring soluble human fatty acid-binding protein [H-FABP] (CardioDetect) for the pre-hospital detection of myocardial infarction (MI).We enrolled prospectively 108 consecutive patients with acute ischemic type chest pain in whom the first medical care was delivered by a mobile intensive care unit (MICU). CTnI, myoglobin, CK-MB and CardioDetect were first assessed in the MICU before hospital admission using point-of-care assays and then cTnI was serially measured during the hospital stay. MI was defined as a positive cTnI in any sample over the first 24 h. The vast majority of the patients (77/108) were admitted3 h of symptoms onset. Pre-hospital cTnI sample was normal in 96 patients (88.9%) of whom 43 had subsequent cTnI elevation. A positive H-FABP using the CardioDetect assay had a significantly better sensitivity than cTnI, myoglobin and CK-MB (87.3% vs 21.8%, 64.2% and 41.5%, respectively) to identify MI. The significant better sensitivity of the CardioDetect assay was also observed among patients who presented3 h of symptom onset. The specificity of the CardioDetect assay was significantly better than that of myoglobin, irrespective of the time delay from symptom onset to measurement. In patients with normal pre-hospital cTnI and no ST-elevation (n=63), assessment based only on a positive H-FABP had 83.3% sensitivity, 93.3% specificity for the diagnosis of an evolving MI.Early assessment of H-FABP in patients presenting with chest pain improves the diagnosis of ongoing MI.

International audience; Otopalatodigital spectrum disorders (OPDSD) constitute a group of dominant X-linked osteochondrodysplasias including four syndromes: otopalatodigital syndromes type 1 and type 2 (OPD1 and OPD2), frontometaphyseal dysplasia, and Melnick-Needles syndrome. These syndromes variably associate specific facial and extremities features, hearing loss, cleft palate, skeletal dysplasia and several malformations, and show important clinical overlap over the different entities. FLNA gain-of-function mutations were identified in these conditions. FLNA encodes filamin A, a scaffolding actin-binding protein. Here, we report phenotypic descriptions and molecular results of FLNA analysis in a large series of 27 probands hypothesized to be affected by OPDSD. We identified 11 different missense mutations in 15 unrelated probands (n=15/27, 56%), of which seven were novel, including one of unknown significance. Segregation analyses within families made possible investigating 20 additional relatives carrying a mutation. This series allows refining the phenotypic and mutational spectrum of FLNA mutations causing OPDSD, and providing suggestions to avoid the overdiagnosis of OPD1.

Hubert Christophe. Le temps de l'imprescriptibilité. In: Revue juridique de l'Ouest, 2002-3. pp. 335-342.

The manipulation and precise control of molecular order is a challenging prospect in the design and realization of devices for photonic applications. A new concept for microstructuration, based on photoinduced molecular migration in polymer films containing an azobenzene dye, was recently demonstrated. Irradiation with an interference pattern of polarized laser beams leads to substantial reversible mass-transport. We now show evidence that under specific experimental conditions, the interaction between a uniform beam from an argon-ion laser and the polymer film induces hexagonal structures on the surface of the polymer. The self-patterning process was observed to depend on several parameters such as the polarization of the laser beam, the angle of incidence and the wavelength, as well as the nature of the dye. Understanding the fundamental mechanisms of this photoinduced self-patterning process should open a new route towards optical molecular control of materials microstructures.

Oenococcus oeni is the bacterium most often associated with spontaneous malolactic fermentation (MLF) of wine. During MLF, malic acid is transformed into lactic acid and several metabolites are modified, modulating wine’s total acidity and improving its sensory properties. Previous works have suggested that certain genetic groups of O. oeni strains are associated to different kinds of products. In the present study we have spotted two groups of strains isolated mainly from Burgundy wines, one associated to red wines and the other to white wines. Sequencing 14 genomes of red and white wine strains revealed that they share a common ancestor that probably colonised two different substrates –red and white wine-associated environments–, diverging over time and disseminating to various regions. Their capacity to perform MLF and modify the volatile profile of wine was determined by fermenting a chardonnay wine and analysing its volatile fraction with a non-targeted metabolomics approach by GC-MS. The strains had a different impact on the volatile composition depending on their group of origin. These results show for the first time a correspondence between the product of origin of the strains and the volatile profile of the wines they produce. Furthermore, the genetic features that might be implied in these different phenotypes are examined.

International audience; Neonatal thymectomy in BALB/c mice has been described as a model of gastric mucosa-associated lymphoid tissue (MALT) lymphoma (GML). By using this experimental system, we screened, for the first time to our knowledge, Helicobacter pylori GML-associated strains for their capacity to promote disease. A cohort of BALB/c mice underwent thymectomy at day 3 after birth (d3Tx). Successful thymic ablation was evaluated by the degree of lymphopenia in blood samples collected at 4 weeks of age. d3Tx and non-thymectomized controls were infected with either GML strains (B38 or B47) or control strains (SS1 or TN2GF4). Gastric samples collected at 6, 12, and 18 months after infection were studied for bacteria content, and submitted to histological, immunochemical, molecular, and immunological analyses. Severe gastric inflammation was only observed in d3Tx mice. In these animals, the gastric lamina propria was infiltrated with lymphoid cells organized in follicles composed of B cells with few infiltrating T cells. PCR of D/J IgH gene segments proved the monoclonality of infiltrating B cells, which strongly correlated with the presence of lymphoepithelial lesions. B-cell infiltrates were particularly prominent in mice infected with the B47-GML strain. No pathological changes were detected in noninfected d3Tx mice. We identified new H. pylori isolates adapted to the mouse stomach with high potential of GML development, which is only revealed in hosts rendered lymphopenic by neonatal thymic ablation.

SummaryThe Genetic Markers for Thrombosis (GMT) study compared the relative influence of ethnicity and thrombotic phenotype regarding the distribution of SNPs implicated in haemostasis pathophysiology (“haemostaseome”). We assessed 384 SNPs in three groups, each of 480 subjects: 1) general population of Aquitaine region (Southwestern France) used as control; 2) patients with venous thromboembolism from the same area; and 3) autochthonous Basques, a genetic isolate, who demonstrate unusual characteristics regarding the coagulation system. This study sought to evaluate i) the value of looking for a large number of genes in order to identify new genetic markers of thrombosis, ii) the value of investigating low risk factors and potential preferential associations, iii) the impact of ethnicity on the characterisation of markers for thrombosis. We did not detect any previously unrecognised SNP significantly associated with thrombosis risk or any preferential associations of low-risk factors in patients with thrombosis. The sum of ϰ2 values for our 110 significant SNPs demonstrated a smaller genetic distance between patients and controls (321 cumulated ϰ2 value) than between Basques and controls (1,570 cumulated ϰ2 value). Hence, our study confirms the genetic particularity of Basques especially regarding a significantly lower expression of the non-O blood group (p< 0.0004). This is mitigated by a higher prevalence of factor II Leiden (p< 0.02) while factor V Leiden prevalence does not differ. Numerous other differences covering a wide range of proteins of the haemostaseome may result in an overall different genetic risk for venous thromboembolism.

Hubert Christophe. Le nouveau droit de la garde à vue. In: Revue juridique de l'Ouest, 2001-1. pp. 69-87.

Cette recherche s’intéresse aux espaces équivoques, soit des espaces jugés ambigus en raison des modes d’appropriation qu’on y retrouve. Par un processus heuristique et à l’aide d’une double étude de cas exploratoire, qui emprunte des méthodes de recherche ethnographiques, cette recherche a pour objectif de mieux caractériser les espaces équivoques. Les deux espaces considérés, tous deux situés dans la partie nord de l’arrondissement du Plateau-Mont-Royal à Montréal, sont un terrain vague informellement appelé le Parc sans Nom et une friche industrielle informellement appelée le Champ des Possibles. Les positions des gestionnaires municipaux et des usagers des deux sites seront analysées selon trois dimensions : les contraintes physiques, les mesures coercitives et les perceptions du risque et du potentiel de conflits. Les résultats issus de ces analyses permettent de constater que les espaces équivoques émergent par processus de co-construction. Ces résultats permettent également de soulever des pistes de réflexion sur les rapports entre les individus et l’espace urbain., This research takes an interest in the equivocal spaces, which means the ambiguous spaces resulting form different forms of spatial appropriation that take place in them. By a heuristic process and with an exploratory two case studies, which use ethnographic research methods, this master thesis aims to characterize the equivocal spaces. The two spaces considered, both situated in the north part of the Plateau-Mont-Royal’s borough in Montreal, are a wasteland informally called Parc sans Nom and an industrial vacant lot informally called Champ des Possibles. With a qualitative approach, the positions of the municipal authorities and of the users of the two sites, in terms of the physical constraints, the coercive measures and the perceptions of risk and potential of conflict in the two spaces, will be analyzed. The results of this analysis allow us to find that the equivocal spaces emerge from a co-construction process. The results allow us also to underline some considerations on the people’s relationship to urban space.

Bilateral periventricular nodular heterotopia (BPNH) is the most common form of periventricular heterotopia. Mutations in FLNA, encoding filamin A, are responsible for the X linked dominant form of BPNH (FLNA-BPNH). Recently, atypical phenotypes including BPNH with Ehlers-Danlos syndrome (BPNH-EDS) have been recognised. A total of 44 FLNA mutations have so far been reported in this phenotype. Most of these mutations lead to a truncated protein, but few missense mutations have also been described. Here, the results of a mutation screening conducted in a series of 32 BPNH patients with the identification of 12 novel point mutations in 15 patients are reported. Nine mutations were truncating, while three were missense. Three additional patients with BPNH-EDS and a mutation in FLNA are described. No phenotype-genotype correlations could be established, but these clinical data sustain the importance of cardiovascular monitoring in FLNA-BPNH patients.

International audience; We demonstrate near-field polarization-sensitive photochemical imaging of the optical near fields produced by metal nanostructures under a variety of illumination conditions. The method relies on the optically induced vectorial molecular mass transport of a light-sensitive polymer. The experimental and theoretical results clearly show that this method can map the three spatial components of the optical near field of complex metal nanostructures. The method was applied to map the electromagnetic near field of silver bowtie nanostructures. In particular, we find that longitudinally polarized plasmons are confined at the top of the metallic structures. Furthermore, the intricate optical near fields in the polymer lead to molecular trapping regions at intensity minima.

Study Objective To evaluate local anesthetic spread on the frequency of success of musculocutaneous nerve block, and to determine needle-to-target-nerve distance by ultrasound imaging and electrical stimulation. Design Observational study. Settings Private hospital. Patients 48 ASA physical status I and II adults (16 men and 32 women) scheduled for elective carpal tunnel release or wrist ganglion cyst surgery in an outpatient setting. Interventions The musculocutaneous nerve (MCN) was identified by ultrasound. An insulated needle connected to an electrical stimulator in the "off" position was inserted in the biceps side of the probe in the plane of the ultrasound beam. The needle tip was placed in the vicinity of the MCN. Measurements Local anesthetic spread pattern was determined by ultrasound imaging. The lowest effective current intensity was registered. The average depth of the MCN was measured by ultrasound. Main Results In all patients, the local anesthetic solution spread was uneven. In 32% of patients (15/47), motor response was still elicited with electrical stimulation intensity lower or equal to 0.3 mA. In 26% of patients (12/47), motor response disappeared with electrical stimulation intensity higher or equal to 0.6 mA. In 42% of patients (20/47), motor response disappeared at intensities between 0.3 mA and 0.5 mA. Conclusions A high success rate of MCN anesthesia occurred with non-circumferential spread of local anesthetic solution. Electrical current intensity was not a reliable indicator of needle-to-target-nerve distance.

International audience; We describe the spontaneous photoinduced patterning of azo-dye polymer films. We have observed that the illumination of an azo-dye polymer film by a uniform single laser beam with normal incidence leads to a self-structurization process that results in the formation of well-ordered submicrometer-sized structures whose organization depends on the light polarization direction. A modulation depth as high as 100 nm can be achieved. The influence of several experimental parameters on the structure formation is studied. Results are discussed and confronted to different models and phenomena already investigated in the literature. A physical origin to this peculiar photopatterning process is proposed

2 cm diameter hydrothermal ZnO crystals were grown and then made into substrates using both mechanical and chemical-mechanical polishing (CMP). CMP polishing showed superior results with an (0002) Ω scan full width half maximum (FWHM) of 67 arcsec and an root mean square (RMS) roughness of 2 A. In comparison, commercial melt-grown substrates exhibited broader X-ray diffraction (XRD) linewidths with evidence of sub-surface crystal damage due to polishing, including a downward shift of c-lattice parameter. Secondary ion mass spectroscopy revealed strong Li, Fe, Co, Al and Si contamination in the hydrothermal crystals as opposed to the melt-grown substrates, for which glow discharge mass spectroscopy studies had reported high levels of Pb, Fe, Cd and Si. Low temperature photoluminescence (PL) studies indicated that the hydrothermal crystal had high defect and/or impurity concentrations compared with the melt-grown substrate. The dominant bound exciton for the melt-grown substrate was indexed to Al. ZnO films were grown using pulsed laser deposition. The melt-grown substrates gave superior results with XRD (0002) Ω and 2θ/Ω WHM of 124 and 34 arcsec, respectively. Atomic force microscope measurements indicated a low RMS roughness (1.9 nm) as confirmed by fringes in the XRD 2θ/Ω scan. It was suggested that the improvement in XRD response relative to the substrate might be due to “healing” of sub-surface polishing damage due to the elevated Ts used for the growth. Indeed the c-lattice parameter for the homoepitaxial layer on the melt-grown substrate had become that which would be expected for strain-free ZnO. Furthermore, the stability of the PL peak positions relative to bulk ZnO, confirmed that the films appear practically strain free.

International audience

International audience; The sub-diffraction imaging of the optical near-field in nanostructures, based on a photochemical technique, is reported. A photosensitive azobenzene-dye polymer is spin coated onto lithographic structures and is subsequently irradiated with laser light. Photoinduced mass transport creates topographic modifications at the polymer film surface that are then measured with atomic force microscopy (AFM). The AFM images correlate with rigorous theoretical calculations of the near-field intensities for a range of different nanostructures and illumination polarizations. This approach is a first step toward additional methods for resolving confined optical near fields, which can augment scanning probe methodologies for high spatial resolution of optical near fields.

We report on the direct observation of optical near-field enhancement around metallic nanoparticles. We used an easy to set up approach which consists in irradiating a photosensitive azo-dye polymer film spin-coated on metallic nanostructures. Photoinduced topographical modifications of the polymer film surface are characterized after irradiation by atomic force microscopy (AFM). Comparisons between AFM images and numerical simulations show that these photo-induced topography agrees with the near-field intensity distribution around the nano-structures. The possibility of generating complex structures is demonstrated.

We present a method for mapping the electromagnetic field distribution in the vicinity of noble metal nanoparticles able to sustain localised surface plasmon resonance (LSPR). The field distribution is coded by topographic change in a self-developing photosensitive polymer (PMMA-DR1). Metallic nanostructures are fabricated by e-beam lithography and optically characterised by extinction spectroscopy. Photoinduced topographic changes are checked by means of atomic force microscopy (AFM). The dipolar character of the surface modification around the particles agrees qualitatively with theoretical predictions and a strong correlation between LSPR position and the relief depth is found.

In a classical multilayer organic light emitting diode (OLED) structure, almost 80% of the light emitted happens to be lost following guiding through the different layers. Patterning of the OLEDs structure was already proposed and reported as an interesting solution towards the optimization of an OLED external efficiency. As an alternative to classical lithographic patterning methods which appear to be quite complex, we propose here the implementation of a quite direct and easy-to-set light-induced patterning method using azo-dye polymers. When a polymer film containing azobenzene dyes is irradiated by an interference pattern between polarized laser beams at a wavelength near the chromophore absorption band, the film surface undergoes a direct, reversible and controlled topographic modification. More surprisingly, we have recently experimentally evidenced that uniform irradiation of an azo-dye polymer using a single laser beam with normal incidence onto the polymer film surface could lead to a self structuration process resulting in the formation of a quasi hexagonal surface-relief grating. After a description of the main features related to light-induced surface relief gratings, we show here that this original patterning process offers an interesting solution for control and optimisation of optoelectronic devices such as OLEDs. The guiding properties of both 1D and 2D structures have been studied and their effects on the light emission properties of a patterned electroluminescent polymer have been characterized and compared after angle dependent measurement of the photoluminescence spectrum. Quite efficient decoupling is evidenced.

It is now well established that, in azo-dye polymers repeated trans-cis-trans isomerization cycles induces molecular reorientation leading to quasi-permanent birefringence and dichroism. More recently, it has been shown that irradiation of an azo-polymer thin film with an interference pattern between polarized laser beams can lead to a direct and reversible topographic modification of the polymer film surface resulting in the induction of surface relief gratings in conjunction with the light interference pattern. Here, we provide experimental evidence of an original spontaneous light-assisted submicrometer patterning process. We show that uniform irradiation of an azo-dye polymer using a single collimated laser beam with normal incidence leads to the formation of organized hexagonal patterns. These structures geometry depends on the laser beam polarization : their period is about the irradiation wavelength and their modulation amplitude can reach one hundred nanometers. Possible origin of such process is discussed. Although showing similar features with models or experiments already described in the literature, the origin of light-assisted spontaneous patterning in azo-polymers is still unclear and further complementary investigations are needed. Indeed, accurate determination of the relevant parameters at the origin of such process should enable a full control of the process together with further possible generation of more complex structures.

During the last decade, large effort has been dedicated towards the miniaturization of devices for photonic applications. One of the key points towards this objective is structurization at the nanoscale level. Recently, one-step photoinscription of surface relief gratings onto azo-polymers was demonstrated: when a polymer film containing azobenzene dyes is irradiated by an interference pattern between polarizaed laser beams at a wavelength near the chromophore absorption band, the film surface undergoes a direct, reversible and controlled topographic modification. Grating modulation amplitudes as large as the film thickness can be obtained. In this work we provide experimental evidence of a new spontaneous light-assisted submicrometer hexagonal patterning process. More particularly, we show that uniform irradaiton of an azo-dye polymer using a singel laser beam wtih normal incidence onto the polymer film surface leads to a self structurization process resulting in the formation of a quasi hexagonal grating. The influence of parameters such as the laser intensity, the irradiation time, the thickness of the polymer film but also the irradiation wavelength is studied towards a better understanding of the process. Full control of the mechanisms at the origin of such process could further permit a complete manipulation of the molecular order and thus enable the generation of other spontaneous complex structures opening the way to the development of new easy-to-set micro and nano-structuration technqiues.