Search

Analysis of thermal capillary waves on the surface of a liquid usually assumes incompressibility of the bulk fluid. However, for droplets or bubbles with submicronic size, or for epithelial cells whose out-of-plane elongation can be modeled by an effective 2D bulk modulus, compressibility of the internal fluid must be taken into account for the characterization of their shape fluctuations. We present a theoretical analysis of the fluctuations of a two-dimensional compressible droplet. Analytical expressions for area, perimeter and energy fluctuations are derived and compared with Cellular Potts Model (CPM) simulations. This comparison shows a very good agreement between theory and simulations, and offers a precise calibration method for CPM simulations.

A 53-year-old man presented with acute loss of vision, negative scotoma and dyschromatopsia in his left eye. He reported contact with people with severe respiratory syndrome - coronavirus-2 (SARS-CoV-2) 8 days prior symptoms. Funduscopic examination revealed several retinal hemorrhages. Spectral-domain optical coherence tomography showed lesions consistent with acute macular neuroretinopathy and paracentral acute middle maculopathy. Quickly after his presentation, SARSCov-2 was confirmed by chest computed tomography-scan and RT-PCR in this patient. Thrombotic complications associated with Covid-19 infection have high incidence and may involve the retina. We described a case of retinal involvement associated with Covid-19 infection.Funduscopic examination revealed retinal hemorrhages in a man with loss of vision. Optical coherence tomography showed an acute macular neuroretinopathy and paracentral acute middle maculopathy. Coronavirus disease was confirmed by chest computed tomography-scan and RT-PCR.

We described three clinical cases of pyogenic liver abscess caused by hypervirulent Klebsiella pneumoniae (hvKp) successfully treated by prolonged antibiotherapy, in which one case was complicated by endophthalmitis. Whole genome sequencing helped to confirm the diagnosis of these hvKp strains, which belong to clonal complexes CC86 and CC23 and carried hvKp-associated genes (magA and/or rmpA). This syndrome is increasingly reported in France and Europe and raises questions about the source of infection.

Background Safety of HPV vaccines is still in question due to reports of autoimmune diseases (ADs) following HPV immunization. Objectives To assess the risk of ADs associated with HPV vaccination of female adolescents/young adults in France. Methods Systematic prospective case-referent study conducted to assess the risks associated with real-life use of HPV vaccines. Cases were female 11–25 years old with incident ADs [central demyelination/multiple sclerosis (CD/MS), connective tissue disease (CTD), Guillain-Barre syndrome (GBS), type-1 diabetes (T1D), autoimmune thyroiditis (AT), and idiopathic thrombocytopenic purpura (ITP)]. Cases were consecutively and prospectively identified at specialized centers across France (2008–2014) and individually matched by age and place of residence to referents recruited in general practice. Risk was computed using multivariate conditional logistic regression models adjusted for family history of ADs, living in France (north/south), co-medications and co-vaccinations. Results With a total of 478 definite cases matched to 1869 referents, all ADs combined were negatively associated to HPV vaccination with an adjusted odds ratio of 0.58 (95% confidence interval: 0.41–0.83). Similar results were obtained for CD/MS, AT, CT, and T1D, the last two not reaching statistical significance. No association was found for ITP and GBS. Sensitivity analyses combining definite and possible cases with secondary time window showed similar results. Conclusion Exposure to HPV vaccines was not associated with an increased risk of ADs within the time period studied. Results were robust to case definitions and time windows of exposure. Continued active surveillance is needed to confirm this finding for individual ADs.

The aim of our study was to investigate possible differences in nailfold videocapillaroscopy (NVC) features between patients with dermatomyositis (DM), overlap myositis (OM), antisynthetase syndrome (ASS), and immune-mediated necrotizing myopathy (IMNM).We performed a cross-sectional monocentric study. All patients with inflammatory myopathies (IMs) over a 6-month period were analyzed by NVC for giant and ramified capillaries, tortuosities, capillary density, disorganization, and scleroderma pattern. Clinical, biological, and pathological characteristics were retrospectively recorded. Patients were classified as having DM, OM, ASS, or IMNM for comparison. Patients were also compared with a group of patients with systemic sclerosis (SSc).NVC was analyzed in DM (n = 17), OM (n = 8), ASS (n = 12), and IMNM (n = 6). Vascular disorganization and avascular zones were observed only in DM (11.8%) and OM (62.5%). The percentage of patients with giant capillaries was higher in OM (n = 4/8) than in DM (n = 3/17) and absent in ASS and IMNM. Frequency of ramified capillaries, tortuosities, hemorrhages, or thrombosis was not different between subgroups. A scleroderma pattern was only observed in OM patients.In this limited series of patients, we observed that DM and OM NVC abnormalities are different from ASS and IMNM. We could not determine NVC specific patterns associated with myositis-specific antibody subtypes of DM because of the small number of patients.Key Points• Nailfold videocapillaroscopy abnormalities are different in subgroups of inflammatory myopathies.• Giant capillaries, disorganization, and major capillary loss are observed in overlap myositis and dermatomyositis but not in antisynthetase syndrome (ASS) or immune-mediated necrotizing myopathy.• Nailfold videocapillaroscopy abnormalities in overlap myositis (with the exclusion of ASS) are close to systemic sclerosis.

International audience; PURPOSE: Immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AIHA) are associated in the definition of Evans syndrome (ES). The occurrence of neurological involvement in this population is poorly described and suggests an underlying primary immunodeficiency (PID). We aimed to describe the clinical manifestations, evolution, and PID profiles of these patients.METHODS: OBS'CEREVANCE is a French, nationwide prospective cohort that includes children with chronic ITP, AIHA, and ES. Patients with a neurological involvement were described. Centralized radiological and pathological reviews and genetic analyses were performed.RESULTS: On October 2016, eight patients (7/181 ES, 1/371 AIHA, and 0/615 ITP) were identified, all male, with a median age (range) at cytopenia onset of 11.5 years (1.6-15.8). Neurological symptoms appeared with a median delay of 6 years (2.5-18) after cytopenia and were polymorphic: seizures (n = 4), cranial nerve palsy (n = 2), Brown-Sequard syndrome (n = 2), intracranial pressure (n = 2), vertigo (n = 1), and/or sensory neuropathy (n = 1). Magnetic resonance imaging (MRI) showed inflammatory lesions, confirmed by pathology for five patients with macrophagic or lymphoplasmocytic infiltrates. All patients had other relevant immunopathological manifestations: pulmonary nodules (n = 6), lymphoproliferation (n = 4), abnormal immunophenotype (n = 8), and hypogammaglobulinemia (n = 7). Treatment consisted of steroids that improved symptomatology and MRI. Five patients relapsed and three had an asymptomatic radiological progression. A PID was identified in 3/8 patients: 22q11.2 microdeletion (n = 1) and CTLA deficiency (n = 2).CONCLUSION: Neurological involvement is a rare and severe late event in the course of childhood ES, which can reveal an underlying PID. Imaging and pathology examination highlight a causative immune dysregulation that may guide targeted therapeutic strategies.

International audience; We describe the clinical, hematologic and genetic characteristics of a retrospective series of 126 subjects from 64 families with hereditary xerocytosis. Twelve patients from six families carried a KCNN4 mutation, five had the recurrent p.Arg352His mutation and one had a new deletion at the exon 7-intron 7 junction. Forty-nine families carried a PIEZO1 mutation, which was a known recurrent mutation in only one-third of the cases and private sequence variation in others; 12 new probably pathogenic missense mutations were identified. The two dominant features leading to diagnosis were hemolysis that persisted after splenectomy and hyperferritinemia, with an inconstant correlation with liver iron content assessed by magnetic resonance imaging. PIEZO1-hereditary xerocytosis was characterized by compensated hemolysis in most cases, perinatal edema of heterogeneous severity in more than 20% of families and a major risk of post-splenectomy thrombotic events, including a high frequency of portal thrombosis. In KCNN4-related disease, the main symptoms were more severe anemia, hemolysis and iron overload, with no clear sign of red cell dehydration; therefore, this disorder would be better described as a ‘Gardos channelopathy’. These data on the largest series to date indicate that PIEZO1-hereditary xerocytosis and Gardos channelopathy are not the same disease although they share hemolysis, a high rate of iron overload and inefficient splenectomy. They demonstrate the high variability in clinical expression as well as genetic bases of PIEZO1-hereditary xerocytosis. These results will help to improve the diagnosis of hereditary xerocytosis and to provide recommendations on the clinical management in terms of splenectomy, iron overload and pregnancy follow-up.

International audience; We consider the hydrodynamics of lipid bilayers containing transmembrane proteins of arbitrary shape. This biologically-motivated problem is relevant to the cell membrane, whose fluctuating dynamics play a key role in phenomena ranging from cell migration, intercellular transport, and cell communication. Using Onsager's variational principle, we derive the equations that govern the relaxation dynamics of the membrane shape, of the mass densities of the bilayer leaflets, and of the diffusing proteins' concentration. With our generic formalism, we obtain several results on membrane dynamics. We find that proteins that span the bilayer increase the intermonolayer friction coefficient. The renormalization, which can be significant, is in inverse proportion to the protein's mobility. Second, we find that asymmetric proteins couple to the membrane curvature and to the difference in monolayer densities. For practically all accessible membrane tensions (σ > 10 −8 N/m) we show that the protein density is the slowest relaxing variable. Furthermore, its relaxation rate decreases at small wavelengths due to the coupling to curvature. We apply our formalism to the large-scale diffusion of a concentrated protein patch. We find that the diffusion profile is not self-similar, owing to the wavevector dependence of the effective diffusion coefficient.

Background We conducted a monocentric retrospective study of patients with myelodysplastic syndromes (MDS) and autoimmune or inflammatory disorders (AIMs) and a literature review. We analyzed the association with subgroups of the WHO 2016 MDS classification and patient's survival in a case control study. Risk factors associated with survival were analyzed by uni- and multivariate analysis. Results From all MDS patients 11% presented with AIMs. These were heterogeneous and the most frequent where polyarthritis (25%) and autoimmune cytopenias (17%). No difference for frequency and type of AIMs was observed for the WHO 2016 MDS subgroups (p = .3). In the case control study WHO classification, karyotype abnormalities, IPSS-R and IPSS were similar in both groups. The overall survival from MDS diagnosis was better in the group with AIMs [10.3 ± 0.6 (IC95% 6.2–12.9) versus 4.8 ± 1.1 years (IC95% 4.2–8.7), p = .04]. The better survival was restricted to MDS with low or intermediate-1 IPSS [11.1 ± 1.5 (IC95% 9.9-NR) versus 8.7 ± 1.3 years (IC95% 4.8–10.3), p = .006]. The better survival was only observed when AIMs diagnosis was timely associated or appeared after MDS diagnosis (p = .04). Factors associated with a better overall survival and survival without AML were steroid dependence [respectively HR = 0.042, p = .003, (IC95% 0.005–0.33) and HR = 0.07, p = .002, (IC95% 0.013–0.39)], a diagnosis of AIMs and MDS timely associated [respectively HR = 0.05, p = .009, (IC95% 0.006–0.478) and HR = 0.1, p = .008, (IC95% 0.018–0.54)] or a diagnosis of AIMs after MDS [respectively HR = 0.024, p = .009, (IC95% 0.001–0.39) and HR = 0.04, p = .008, (IC95% 0.003–0.43)]. Conclusion Autoimmune and inflammatory diseases associated to MDS are heterogeneous. AIMs diagnosed after or concomitantly to MDS seems associated with a better survival. Prospective studies are necessary to demonstrate that autoimmunity is associated to a better control of the MDS clone.

Purpose Safety and organizational research indicates that fostering resilience in organizations is a promising way for improving safety, albeit concrete means to implement resilience are still lacking, especially in the educational field. The purpose of this paper is to propose four principles for training design derived from past and current studies the authors conduct in high-risk organizations. Design/methodology/approach Training for resilience is considered within an enactive approach of human activity building on its properties of autonomy, structural coupling, self-organization, emergence, sensemaking, and metastability. Findings The article describes four educational design principles aiming at improving individual, collective, and organizational resilience: encourage mimetic experiences; pay attention to attention and concernedness; perturb and turn into an event; support participatory-sensemaking and collective sensemaking. Research limitations/implications The training program the authors propose may be challenging to assess. Besides, the most durable solutions to improve safety through resilience are to be found at the crossroad between organizational design and training/development policies. Future research should determine the implementability criteria which are likely to support the use of the principles the authors propose, and contribute to enrich this educational foundation. Originality/value Education and training are conceived herein as high-order means to improve safety through resilience in high-risk organizations, fostering the capacity of the operators and organization to develop efficiently and in the long run. We provide independent but complementary training principles that cannot be hierarchized, but that can be locally prioritized in organizations.

Anatomical models to study aerosol delivery impose huge limitations and extrapolation to humans remains controversial. This study aimed to develop and validate an ex vivo human-like respiratory tract model easy to use and relevant to compare to in vivo human data. A human plastinated head is connected to an ex vivo porcine pulmonary tract ventilated artificially by passive expansion. A physiological study measures “pleural” depressions, tidal volumes, and minute ventilation for the respiratory rates chosen (10, 15, and 20 per minute) with three inspiratory/expiratory ratios (1/1, 1/2, and 1/3). Scintigraphy with 81mKrypton assesses the homogeneity of the ventilation. Forty different experiments were set for validation, with 36 (90%) ventilating successfully. At a respiratory rate of 15/minute with inspiratory/expiratory ratio of 1/2, the tidal volume average was 824 mL (standard deviation, 207 mL). The scintigraphy performed on 16 ex vivo models (44.4%), showed homogenous ventilation with great similarity to human physiological studies. Ratio of the peripheral to central count rates were equally correlated with human data published in the literature. This new model, combining research feasibility and human physiology likeness, provides a realistic approach to human inhalation and therefore can be an interesting tool in aerosol regional deposition studies.

International audience; The Cellular Potts Model (CPM) is a lattice based modeling technique which is widely used for simulating cellular patterns such as foams or biological tissues. Despite its realism and generality, the standard Monte Carlo algorithm used in the scientific literature to evolve this model preserves connectivity of cells on a limited range of simulation temperature only. We present a new algorithm in which cell fragmentation is forbidden for all simulation temperatures. This allows to significantly enhance realism of the simulated patterns. It also increases the computational efficiency compared with the standard CPM algorithm even at same simulation temperature, thanks to the time spared in not doing unrealistic moves. Moreover, our algorithm restores the detailed balance equation, ensuring that the long-term stage is independent of the chosen acceptance rate and chosen path in the temperature space.

Background The knowledge of where particles deposit in the respiratory tract is crucial for understanding the health effects associated with inhaled drug particles. Method An ex vivo study was conducted to assess regional deposition patterns (thoracic vs. extrathoracic) of radioactive polydisperse aerosols with different size ranges [0.15 μm–0.5 μm], [0.25 μm–1 μm] and [1 μm–9 μm]. SPECT/CT analyses were performed complementary in order to assess more precisely the regional deposition of aerosols within the pulmonary tract. Experiments were set using an original respiratory tract model composed of a human plastinated head connected to an ex vivo porcine pulmonary tract. The model was ventilated by passive expansion, simulating pleural depressions. Aerosol was administered during nasal breathing. Results Planar scintigraphies allowed to calculate the deposited aerosol fractions for particles in the three size ranges from sub-micron to micron The deposited fractions obtained, for thoracic vs. extra-thoracic regions respectively, were 89 ± 4 % vs. 11 ± 4 % for [0.15 μm–0.5 μm], 78 ± 5 % vs. 22 ± 5 % for [0.25 μm–1 μm] and 35 ± 11 % vs.65 ± 11 % for [1 μm–9 μm]. Conclusion Results obtained with this new ex vivo respiratory tract model are in good agreement with the in vivo data obtained in studies with baboons and humans.

International audience; The purpose of this study was to understand how a single pair of expert individual rowers experienced their crew functioning in natural conditions when asked to practice a joint movement for the first time. To fulfill this objective, we conducted a field study of interpersonal coordination that combined phenomenological and mechanical data from a coxless pair activity, to analyze the dynamics of the (inter)subjective experience compared with the dynamics of the team coordination. Using an enactivist approach to social couplings, these heterogeneous data were combined to explore the salience (and accuracy) of individuals' shared experiences of their joint action. First, we determined how each rower experienced the continuous crew functioning states (e.g., feelings of the boat's glide). Second, the phenomenological data helped us to build several categories of oar strokes (i.e., cycles), experienced by the rowers as either detrimentally or effectively performed strokes. Third, the mechanical signatures that correlated with each phenomenological category were tracked at various level of organization (i.e., individual-, interpersonal-, and boat-levels). The results indicated that (a) the two rowers did not pay attention to their joint action during most of the cycles, (b) some cycles were simultaneously lived as a salient, meaningful experience of either a detrimental (n = 15 cycles) or an effective (n = 18 cycles) joint action, and (c) the mechanical signatures diverged across the delineated phenomenological categories, suggesting that the way in which the cycles were experienced emerged from the variance in some mechanical parameters (i.e., differences in peak force level and mean force). Notably, the mechanical measures that helped to explain differences within the phenomenological categories were found at the interpersonal level of analysis, thus suggesting an intentional inter-personal mode of regulation of their joint action. This result is further challenged and discussed in light of extra-personal regulation processes that might concurrently explain why participants did not make an extensive salient experience of their joint action. We conclude that attempts to combine phenomenological and mechanical data should be pursued to continue the research on how individuals regulate the effectiveness of their joint actions' dynamics.

Background Mycoplasma pneumoniae is a bacterium responsible for 15 to 40 % of acute community-acquired pneumonia in children and 20 % of adult cases. Several extrapulmonary manifestations have been reported. We report a rare case of an adult patient suffering from pneumonia associated with an acute pancreatitis in the setting of Mycoplasma pneumoniae infection. Case presentation A 28-year-old Caucasian woman was referred for anorexia lasting for 1 week. Her past medical history was notable for congenital hydrocephalus with consecutive ventriculo-peritoneal shunt, epilepsia and paraparesis. The patient rapidly deteriorated, presenting with dyspnea, tachypnea, productive cough, abdominal pain, and onset of fever. C-reactive protein was at 270 mg/L, with a rise in serum lipase (670 UI/L, N: 13–60). A computed-tomography scan showed an acute interstitial edematous pancreatitis without necrosis, consistent with grade C on the Balthazar score. Thoracic sections revealed diffuse parenchymal consolidations combined with ground glass opacities. Calcium and triglyceride levels were normal. There was no history of recent trauma, alcoholic intake or drug intoxication. Mycoplasma pneumoniae serological assay showed an elevated IgM titer (22 UA/mL), compatible with recent infection, and cold agglutinins were present. A diagnosis of acute pancreatitis and diffuse interstitial pneumonia caused by an infection with Mycoplasma pneumoniae was considered. Respiratory and abdominal evolution was quickly favorable after initiation of clarithromycin 500 mg bid. Conclusions The relationship between Mycoplasma pneumoniae infection and acute pancreatitis has been debated in the literature for many years. This observation, supported by clinical, biological and radiological features, is an additional argument in favor of a non-fortuitous association.

for the PGRx-ITP Study Group; International audience; This prospective observational cohort study aimed to explore the clinical features of incident immune thrombocytopenia in adults and predictors of outcome, while determining if a family history of autoimmune disorder is a risk factor for immune thrombocytopenia. All adults, 18 years of age or older, recently diagnosed with immune thrombocytopenia were consecutively recruited across 21 hospital centers in France. Data were collected at diagnosis and after 12 months. Predictors of chronicity at 12 months were explored using logistic regression models. The association between family history of autoimmune disorder and the risk of developing immune thrombocytopenia was explored using a conditional logistic regression model after matching each case to 10 controls. One hundred and forty-three patients were included: 63% female, mean age 48 years old (Standard Deviation=19), and 84% presented with bleeding symptoms. Median platelet count was 10×109/L. Initial treatment was required in 82% of patients. After 12 months, only 37% of patients not subject to disease-modifying interventions achieved cure. The sole possible predictor of chronicity at 12 months was a higher platelet count at baseline [Odds Ratio 1.03; 95%CI: 1.00, 1.06]. No association was found between outcome and any of the following features: age, sex, presence of either bleeding symptoms or antinuclear antibodies at diagnosis. Likewise, family history of autoimmune disorder was not associated with incident immune thrombocytopenia. Immune thrombocytopenia in adults has been shown to progress to a chronic form in the majority of patients. A lower platelet count could be indicative of a more favorable outcome.

Purpose The impact of 100 Hz (Hertz) acoustic frequency airflow on sinus drug deposition of aerosols was investigated using a human plastinated nasal cast. The influence of drug concentration and endonasal anatomical features on the sinus deposition enhanced by the 100 Hz acoustic airflow was also examined. Methods Plastinated models were anatomically, geometrically and aerodynamically validated (endoscopy, CT scans, acoustic rhinometry and rhinomanometry). Using the gentamicin as a marker, 286 experiments of aerosol deposition were performed. Changes of airborne particles metrology produced under different nebulization conditions (100 Hz acoustic airflow and gentamicin concentration) were also examined. Results Aerodynamic and geometric investigations highlighted a global behaviour of plastinated models in perfect accordance with a nasal decongested healthy subject. The results of intrasinus drug deposition clearly demonstrated that the aerosols can penetrate into the maxillary sinuses. The 100 Hz acoustic airflow led to increase the deposition of drug into the maxillary sinuses by a factor 2–3 depending on the nebulization conditions. A differential intrasinus deposition of active substance depending on maxillary ostium anatomical features and drug concentration was emphasized. Conclusion The existence of a specific transport mechanism of penetration of nebulized particles delivered with acoustic airflow was proposed.

International audience; BACKGROUND: For many years, researchers have been interested in investigating airflow and aerosol deposition in the nasal cavities. The nasal airways appear to be a complex geometrical system. Thus, in vitro experimental studies are frequently conducted with a more or less biomimetic nasal replica. AIM: This study is devoted to the development of an anatomically realistic nose model with bilateral nasal cavities, i.e. nasal anatomy, airway geometry and aerodynamic properties as close as possible to in vivo behaviour. METHODS: A specific plastination technique of cephalic extremities was developed by the Anatomy Laboratory at the Saint-Etienne University in the last 10 years. The plastinated models obtained were anatomically, geometrically and aerodynamically validated using several techniques (endoscopy, CT scans, acoustic rhinometry and rhinomanometry). RESULTS: Our plastination model exhibited a high level of anatomic quality, including a very good mucosa preservation. Aerodynamical and geometrical investigations highlighted a global behaviour of plastinated models perfectly in accordance with a nasal decongested healthy subject. CONCLUSIONS: The present plastination model provides a realistic cast of nasal airways, and may be a useful tool for nasal flow, drug delivery and aerosol deposition studies.

Objective. Systemic sclerosis (SSc) is a life-threatening autoimmune disease characterized by chronic fibrosis of the skin and internal organs. Connective tissue growth factor (CTGF) is believed to be a primary mediator of chronic fibrosis. We assessed the possible association between 7 single-nucleotide polymorphisms (SNP) in the CTGF gene and scleroderma in a French population (registration number 2006/0182).Methods. We conducted a case-control study with 241 scleroderma patients and 269 controls. Seven SNP were genotyped using the TaqMan system. Univariate and multivariate analyses were performed. In silico electrophoretic mobility shift assay (EMSA), and reverse transcriptase polymerase chain reaction analyses were done to assess the effect of the SNP on CTGF gene expression.Results. The frequency of the rs9399005TT genotype was significantly lower in SSc patients than in controls. This association remained significant after adjustment for gender. An association was detected between the rs9399005 and the diffuse and limited cutaneous forms. Multivariate analysis between SSc patients and controls taking into account all 7 SNP and sex revealed that only sex and the rs9399005 SNP were associated with disease. DNA analysis by EMSA indicated that the T allele bound nuclear factors that were also bound by the C allele. The binding affinity was higher for the T allele. Analysis of the human database and experiments with human hepatocyte cell line indicated the existence of an alternative transcript containing the rs9399005 polymorphism in its 3’UTR region. In silico analysis indicated that this polymorphism may alter the structure of CTGF messenger RNA.Conclusion. These findings suggest that CTGF gene polymorphisms may contribute to susceptibility to scleroderma.

Objectives To characterize the contents of emotions experienced by elite table tennis players during high-stakes matches and the situational elements that contribute to these experiences. Design A four-case study. Method Three top-level table tennis players from the French Men's Table Tennis Team volunteered to participate in the study. Four matches were studied. Procedures involved: (a) videotaping high-stakes table tennis matches, (b) conducting self-confrontation interviews with players after matches, (c) transcribing the players’ actions and self-confrontation data, (d) decomposing their activity into elementary units, and (e) identifying typical contents of emotion and typical emotional situations. Results The contents of players’ emotions varied during matches. The pleasant or unpleasant tone of emotional content was linked to the set result and the interpretations of the unfolding situation. However, other elements of the competitive interaction (score configurations, judgments about the strokes performed) had a strong emotional coloration. Certain similar events (e.g., bad sensations during stroke performance) were frequently coupled with similar emotional content (e.g., displeasure). Conclusions Until quite recently, the predominant focus in sport psychology has been on pre-performance emotions, with far less attention paid to the subjective emotional experiences that occur during task execution. This exploratory study provides initial empirical support for the notion of bi-directionality in emotion–performance relationships [Hanin, Y.L. (Ed.). (2000). Emotions in sport. Champaign, IL: Human Kinetics; Hanin, Y.L. (2003). Performance related emotional states in sport: A qualitative analysis. Forum Qualitative Sozialforschung/Forum: Qualitative Social Research [On-line Journal], 4(1). Available at: http://www.qualitative-research.net/fqs-texte/1-03/1-03hanin-e.htm ].

International audience; This article describes the main features of a collaborative project involving researchers, coaches, and elite table tennis players. The project was carried out between 1997 and 2002 with funding from the French Ministry of Youth and Sports, in response to a request by French Table Tennis Team coaches to improve the training of table tennis players. Matches were videotaped during international meets and followed by interviews during which the players described and commented on their activity as they viewed the tapes. A grounded theory of players' activity emerged from the data collected and the ensuing theoretical issues that were raised. The findings on table tennis players' activity pointed to a new direction for training proposals, for example the organization of reflexive practices during training.

This study analyzed the elite athletes' activity within a competitive context. Based on situated cognition principles, this activity was expected to display various types of coupling with the setting. Seven trampolinists volunteered to participate in the analysis of five international competitions. The method consisted of transforming the data collected by video recording, field notes, and self-confrontation interviews into a chain of units of meaning in order to reconstruct the global dynamics of the action–situation coupling. The results indicated singular forms of couplings and evolving dynamic of activity with four different modes: (a) exploration, (b) holding back, (c) internalization, and (d) relaxation. Discussion highlights the distributed character of activity in the social and physical environment. Situation is progressively constructed and defined by a set of artifacts that reflect a situated cognition.

International audience; Purpose:Improvement of clinical outcome in patients with sinuses disorders involves targeting delivery of nebulized drug into the maxillary sinuses. We investigated the impact of nebulization conditions (with and without 100 Hz acoustic airflow), particle size (9.9 μm, 2.8 μm, 550 nm and 230 nm) and breathing pattern (nasal vs. no nasal breathing) on enhancement of aerosol delivery into the sinuses using a realistic nasal replica developed by our team.Methods:After segmentation of the airways by means of high-resolution computed tomography scans, a well-characterized nasal replica was created using a rapid prototyping technology. A total of 168 intrasinus aerosol depositions were performed with changes of aerosol particle size and breathing patterns under different nebulization conditions using gentamicin as a marker.Results:The results demonstrate that the fraction of aerosol deposited in the maxillary sinuses is enhanced by use of submicrometric aerosols, e.g. 8.155 ± 1.476 mg/L of gentamicin in the left maxillary sinus for the 2.8 μm particles vs. 2.056 ± 0.0474 for the 550 nm particles. Utilization of 100-Hz acoustic airflow nebulization also produced a 2- to 3-fold increase in drug deposition in the maxillary sinuses (e.g. 8.155 ± 1.476 vs. 3.990 ± 1.690 for the 2.8 μm particles).Conclusions:Our study clearly shows that optimum deposition was achieved using submicrometric particles and 100-Hz acoustic airflow nebulization with no nasal breathing. It is hoped that our new respiratory nasal replica will greatly facilitate the development of more effective delivery systems in the future.

International audience; To relate exposure to adverse health effects, it is necessary to know where particles in the submicron range deposit in the respiratory tract. The possibly higher vulnerability of children requires specific inhalation studies. However, radio-aerosol deposition experiments involving children are rare because of ethical restrictions related to radiation exposure. Thus, an in vivo study was conducted using three baboons as a child respiratory tract model to assess regional deposition patterns (thoracic region vs. extrathoracic region) of radioactive polydisperse aerosols ([d16-d84], equal to [0.15 μm-0.5 μm], [0.25 μm-1 μm], or [1 μm-9 μm]). Results clearly demonstrated that aerosol deposition within the thoracic region and the extrathoraic region varied substantially according to particle size. High deposition in the extrathoracic region was observed for the [1 μm-9 μm] aerosol (72% ± 17%). The [0.15 μm-0.5 μm] aerosol was associated almost exclusively with thoracic region deposition (84% ± 4%). Airborne particles in the range of [0.25 μm-1 μm] showed an intermediate deposition pattern, with 49% ± 8% in the extrathoracic region and 51% ± 8% in the thoracic region. Finally, comparison of baboon and human inhalation experiments for the [1 μm-9 μm] aerosol showed similar regional deposition, leading to the conclusion that regional deposition is species-independent for this airborne particle sizes.

International audience; This study analyzed the temporal and contextual organization of coach-athlete interactions in elite archery competitions. In light of the course of action theoretical framework (Theureau, 1992) from ergonomics research, action was conceived as situated (i.e., closely linked to ecological constraints) and was studied at the level at which it is significant for the actor. One expert archery coach and four elite athletes were observed and videotaped during two competitions. The coach's and athletes' verbalizations were also recorded during self-confrontation interviews immediately after each competition. Data processing consisted of: (a) transcribing the coach's and athletes' actions, communication, and self-confrontation data; (b) decomposing action into elementary units of meaning; (c) identifying coherence and similarities of sequences; and (d) examining the coordination of the courses of action of the coach and athlete. The coach's course of action was characterized by respect for the athletes' autonomy, analysis of performance decrements, and emergency interventions. The athletes' courses of action were characterized by autonomy and help-seeking. The coach's and athletes' collective courses of action showed that cooperation within the dyad was either immediate, due to shared perceptions, or was constructed through negotiation. This study outlines the situated and constructed nature of coach-athlete cooperation, and suggests the value of such frameworks from ergonomics, for coaching, and counselling.

National audience; Objectifs : L'administration nasale de médicaments sous forme d'aérosol est largement utilisée par les otorhinolaryngologistes. Bien qu'elle manque d'évaluations cliniques, la nébulisation ORL se présente comme une option thérapeutique intéressante pour l'administration nasale de médicaments. Les aérosols permettraient de cibler les sites anatomiques d'intérêt situés derrière la valve nasale. Le nébuliseur sonique NL11SN utilise l'addition d'un son de 100 Hertz (Hz) à l'aérosol produit afin d'améliorer le dépôt dans les sinus. L'objectif de notre étude était : (1) d'évaluer in vivo chez le volontaire sain l'influence du son sur la ventilation sinusienne et le dépôt nasal et pulmonaire d'un aérosol sonique, et (2) de quantifier in vitro le dépôt d'aérosols soniques dans les sinus maxillaires d'un modèle plastiné. Patients et méthodes : In vivo, une scintigraphie de ventilation au gaz 81mKr et une scintigraphie de dépôt d'aérosol (99mTc-DTPA) sonique produit par le NL11SN étaient réalisées chez sept volontaires sains. En parallèle, des nébulisations de gentamicine étaient réalisées en présence ou en absence du son de 100 Hz sur un modèle de tête humaine plastinée avec le NL11SN. La quantité de gentamicine déposée dans les sinus était dosée par FPIA. Résultats : L'addition du son de 100 Hz au gaz 81mKr permettait la ventilation des cavités sinusiennes des volontaires sains. Le 99mTc-DTPA nébulisé avec le NL11SN chez les volontaires se déposait majoritairement dans les cavités nasales (2/3 vs 1/3 dans les poumons). In vitro, le NL11SN utilisé en mode sonique a permis d'augmenter d'un facteur 3 (p < 0,002) le dépôt de gentamicine dans les sinus du modèle plastiné. Les quantités d'antibiotiques déposées dans les sinus du modèle plastiné pouvaient être considérées comme suffisantes pour avoir un effet thérapeutique local. Conclusions : Le nébuliseur NL11SN assure un dépôt préférentiel de l'aérosol dans les cavités nasales et cible efficacement les sinus maxillaires.

International audience; Aim: Intranasal aerosol administration of drugs is widely used by ENT specialists. Although clinical evidence is still lacking, intranasal nebulization appears to be an interesting therapeutic option for local drug delivery, targeting anatomic sites beyond the nasal valve. The sonic nebulizer NL11SN associates a 100 Hertz (Hz) sound to the aerosolization to improve deposition in the nasal/paranasal sinuses. The aim of the present study was: to evaluate in vivo the influence of associating a 100 Hz sound on sinus ventilation and nasal and pulmonary aerosol deposition in normal volunteers, and; to quantify in vitro aerosol deposition in the maxillary sinuses in a plastinated head model. Material and methods: Scintigraphic analysis of 81mKr gas ventilation and of sonic aerosol (99mTc-DTPA) deposition using the NL11SN was performed in vivo in seven healthy volunteers. In parallel, NL11SN gentamicin nebulization was performed, with or without associated 100 Hz sound, in a plastinated human head model; the gross amount of gentamicin delivered to the paranasal sinuses was determined by fluorescence polarization immunoassay. Results: Associating the 100 Hz sound to 81mKr gas ensured paranasal sinus ventilation in healthy volunteers. 99mTc-DTPA particles nebulized with the NL11SN were deposited predominantly in the nasal cavities (2/3, vs 1/3 in the lungs). In vitro, the use of NL11SN in sonic mode increased gentamicin deposition threefold in the plastinated model sinuses (P < 0.002); the resulting antibiotic deposit would be sufficient to induce a local therapeutic effect. Conclusion: The NL11SN nebulizer ensured preferential nasal cavity aerosol deposition and successfully targeted the maxillary sinuses.

Summary Based on the course-of-action theory, this study performed a situated analysis of three elite aerial freestyle skiers’ activity. Data were collected by observation, videotaping and self-confrontation interviews retrospectively build the athletes’ activity. The analysis identified units of action, thought, and feelings and described their relationships during each leap. Comparisons of the different courses of action revealed six components of freestyle skiers’ activity: (1) pick up speed in the descent, (2) manage the curve of the tremplin, (3) take-off, (4) manage the exit of the tremplin, (5) perform rotations, and (6) organize the landing. This study revealed the dynamic and situated property of acrobatic activity. As the leap unfolded, the athletes step-by-step enhanced their knowledge of what was occurring and what they would have to do to perform their best and land on their feet. Points of convergence and divergence with other acrobatic performances are discussed.

International audience; The aims of this study were to identify and analyse elite athletes' problems in competition. A situated cognition approach placed the emphasis on athletes' actions (i.e. cognitions and behaviours), which were considered to emerge from couplings with selected elements of the context. Fifty-two exercises performed by 10 elite trampolinists were analysed. Field observations, structured interviews, and self-confrontation interviews were conducted and transcribed, and used together with behavioural descriptions derived from video recordings. Performance problems were selected from these reports and from the major infringements of trampoline rules. Qualitative analysis identified the meaningful units of action and their semiotic components for each problem. Four categories of problem were identified and noted to appear either separately or jointly while performing: (a) finding the best moment to begin the performance; (b) finding and maintaining the best mode of involvement to end the performance; (c) recovering normal sensory-motor capacity to perform; and (d) solving problems quickly and definitively while performing. The results suggest that the study of action – situation couplings in sports, as well as of their constantly evolving dynamics, not only reveals elite athletes' psychological activity, but is vital to a deeper understanding of these couplings.

International audience; New surgical techniques require fine control from the surgeon's point of view. Until recently, the necessary experience was only obtainable through traditional training protocols (using cadavers, animals, etc.). However, numerous training simulators have now been developed for use in this area. We present a new approach based on a three-dimensional finite element software and on different kinds of linear and nonlinear elastic constitutive equations that is able to predict realistic results. To classify these equations in terms of accuracy, we performed ex-vivo experimental measurements on lamb kidneys. The software has been applied to soft tissue deformation, namely lamb kidney and human uterus, and the numerical results have been compared to experimental ones.

We analyze the structure of networks minimizing the global resistance to flow (or dissipated energy) with respect to two different constraints: fixed total channel volume and fixed total channel surface area. First, we determine the shape of channels in such optimal networks and show that they must be straight with uniform cross-sectional areas. Then, we establish a relation between the cross-sectional areas of adjoining channels at each junction. Indeed, this relation is a generalization of Murray's law, originally established in the context of local optimization. Moreover, we establish a relation between angles and cross-sectional areas of adjoining channels at each junction, which can be represented as a vectorial force balance equation, where the force weight depends on the channel cross-sectional area. A scaling law between the minimal resistance value and the total volume or surface area value is also derived from the analysis. Furthermore, we show that no more than three or four channels meet in one junction of optimal bi-dimensional networks, depending on the flow profile (e.g.: Poiseuille-like or plug-like) and the considered constraint (fixed volume or surface area). In particular, we show that sources are directly connected to wells, without intermediate junctions, for minimal resistance networks preserving the total channel volume in case of plug flow regime. Finally, all these results are illustrated with a simple example, and compared with the structure of natural networks.

International audience; The course-of-action theory (J. Theureau, Le Cours d'action: Analyse Sémiologique, 1992) provided the framework for this study, which described how expert table tennis players' mobilized knowledge in relation with their mode of involvement (exploratory and executory). Matches were videotaped during international meets and the verbalizations of the players as they viewed the tapes were collected a posteriori. The data were processed by transcribing the players' actions and verbalizations, decomposing their activity into elementary units of meaning, labeling the constituents of these units, identifying typical exploratory and executory sequences. The results showed that the knowledge mobilized by the players during the matches differed with their mode of involvement. Knowledge was continuously put into relationship with significant elements in the unfolding situation in order to create interpretive chains, and this contributed to building a meaningful world for the players. The players' cognitive activity was thus revealed to be a permanent construction of meaning aimed at reducing uncertainty in situations of competitive interaction.; Le but de cette étude était de décrire la manière dont les pongistes mobilisaient des connaissances, en relation avec leurs modes d'engagement (exploratoire et exécutoire), au cours de matchs internationaux. L'étude a été menée en référence au cadre théorique du cours d'action (J. Theureau, Le Cours d'action: Analyse Sémiologique, 1992). Les matchs ont été filmés, et les verbalisations des pongistes confrontés à ces enregistrements ont été recueillies a posteriori. Le traitement des données a consisté à retranscrire les actions des pongistes au cours des matchs et leurs verbalisations provoquées lors des entretiens, identifier les unités significatives élémentaires de chaque cours d'action et leurs composantes sous-jacentes, et identifier les séquences types exploratoires et exécutoires. Les résultats montrent que les connaissances mobilisées par les pongistes lors des matchs différaient selon leur mode d'engagement. La mise en relation de ces connaissances avec les éléments significatifs dans la situation actuelle permettait la création de chaînes interprétatives et contribuait à la construction d'un monde pertinent et significatif pour les pongistes. L'activité cognitive des pongistes consiste ainsi comme une construction permanente de significations visant à réduire l'incertitude de la situation d'interaction compétitive.

Using a situated cognition approach, this study analyzed elite athletes' actions, i.e., behaviors link to cognitions, during competitive trampoline performances, which are evaluated from a succession of 10 acrobatic movements characterized by flight time and fall risk. 27 exercises performed by 10 elite athletes were ranked poor, average, or good and analyzed. Self-confrontation interviews were conducted and transcribed in relation with behavioral descriptions derived from video recordings. Qualitative analysis was performed to identify units of meaningful action and their components. The succession of units describing the stream of actions was used to identify differentiated organization of trampolinists' performances. Three patterns, corresponding to performance levels, were distinguished by (a) an increasing number of meaningful actions occurring at the same time, (b) a reduction in actions of waiting, and (c) the emergence of new actions aimed at interaction with the situation. These results suggest that differentiation in performance level is linked with meaningful actions modified through interaction with the context.

International audience; Computer simulations of minimal invasive procedures have been developed for surgery planning or training or for the evaluation of surgical procedure. In order to perform realistic and precise simulations of surgery on soft tissue, one key step consists in introducing accurate tissue-specific mechanical parameters. The goal of this work was to transfer an indentation procedure from the laboratory to the operating room using a new portable indentation device. The numerical simulations with 3D finite element software of the experiments allowed us to identify the characteristic rheological properties which minimize the gap between computed end measured physical quantities. The next step will be to extend this procedure to pathologic uterus and to other solid organs.

Dans une perspective d’action située, cet article décrit les premières expériences en classe d’enseignants d’éducation physique. La première partie présente les aspects théoriques et méthodologiques du cadre d’analyse retenu. La seconde décrit synthétiquement, puis en s’appuyant sur l’analyse pas à pas d’un cours d’expérience, les traits généraux de trois expériences typiques des enseignants débutants au caractère : a) indéterminé, b) contradictoire et c) exploratoire. La troisième discute l’intérêt du dévoilement de ces expériences typiques dans la constitution d’un dispositif de formation initiale., This article describes the first experiences of physical education teachers within the frame of action research. The first part presents the theoretical and methodological frame of reference for the analysis chosen. The second part describes both a synthesis and, based on a step-by-step analysis of a course, the general characteristics of three typical experiences which beginning teachers face : (a) indeterminate, b) contradictory, and c) exploratory. Finally, the authors discuss the interest of this process of examining typical experiences for developing models for initial teacher training., En una perspectiva de acción localizada, este artículo describe las primeras experiencias en el aula de maestros de educación física. La primera parte presenta los aspectos teóricos y metodológicos del marco de análisis elegido. La secunda describe de manera sintética, y luego fundamentándose en el análisis, paso a paso, de una clase de experimentación, los rasgos generales de tres experiencias típicas de maestros novatos de carácter : a) indeterminado, b) contradictorio y c) exploratorio. La tercera parte examina el interés de la revelación de estas experiencias típicas en la constitución de un dispositivo de formación inicial., Dieser praxisorientierte Artikel beschreibt die ersten Lehrerfahrungen von Sportlehrern. Im ersten Teil werden theoretische und methodologische Aspekte des Analyserahmens abgesteckt. Im zweiten Teil werden zusammenfassend die Gemeinsamkeiten dreier typischer Lehrerfahrungen von Lehranfängern beschrieben, die auf einer Analyse von Einzelerfahrungen beruhen. Die gemachten Erfahrungen lassen sich charakterisieren als : a. unbestimmt, b. widersprüchlich, c. sondierend. Im letzten Teil schließlich wird die Frage aufgeworfen, in wieweit die Veröffentlichung dieser typischen Erfahrungen für den Aufbau einer Grundstudieneinheit interessant sein könnte.

International audience; Two studies investigated the links between goal orientations and conceptions of sport ability. In Study 1, 194 English children (aged 11-12 yrs) completed a psychological inventory which included questions on achievement goal choice and perceptions of the nature of sport ability. In Study 2, 304 French children (aged 11-17 yrs) completed questionnaires, including the French version of the Perception of Success Questionnaire and the Conception of the Nature of Athletic Ability Questionnaire. Clear relationships were observed between a social comparison goal and a conception of athletic ability as a "gift" and being "general," and between a task mastery goal and the conception of athletic ability as being incremental and determined by learning. The measuring of the causal links that unite goals and ability conceptions, as well as the likely impact of such conceptions on motivation were developed and discussed.

International audience; This study assessed the influence of individual and contextual factors on adolescent girls' interest in school physical education (PE). Specifically, girls (N = 700) were assessed on: (1) perceptions of their PE class climate, using the Perceived Motivational Climate Scale (Cury et al, 1994); (2) dispositional achievement goal orientations, using the French version of the Perception of Success Questionnaire (Durand et al, in press); and (3) the interest and competence subscales from the French version of the Intrinsic Motivation Inventory (Cury et al, 1994). Structural equation modelling analysis, using LISREL VII, showed an excellent fit with the hypothesized model. Specifically, situational class climate was found to be more important than individual goals in influencing pupil interest in PE. However, perceived competence also influenced interest, as did a mastery goal orientation. Results are discussed in the context of theoretical propositions of goal perspectives theory and practical issues of enhancing adolescent girls' interest in physical education.

Motivational research in the classroom has adopted a social cognitive perspective but has mainly been restricted to the study of individual achievement cognitions. In addition to this, there is a need to study and assess the perception children have of the class climate. Using social cognitive theory as a base, this research reports the development of class climate scales in French and English for use in physical education classes. Psychometric development with the French scale was shown to be satisfactory, including adequate factorial structure assessed by exploratory and confirmatory factor analysis (CFA), and good internal and test-retest reliability. A parallel English scale demonstrated a less adequate fit to the proposed model when using CFA, but shortened scales assessing just mastery and performance dimensions of climate were shown to predict important motivational measures in a structural equation modelling analysis.

Intranasal nebulisation seems to be the best therapeutic option for local antibiotic delivery, targeting infected sites beyond the nasal valve, especially for CF patients whose maxillary sinuses (MS) may be a source for bacterial inducing lung infections. In this study, we have evaluated the NL11SN sonic nebuliser (100 Hz) on MS ventilation and on aerosol deposition, in an in vitro model and in normal volunteers. Scintigraphy of 81mKr gas ventilation and of 99mTc-DTPA sonic aerosol deposition with NL11SN (DTF, France) was performed in 7 subjects. MS deposition was quantified using an image processing method. In vitro nebulisations were performed in a plastinated head model either with 99mTc-DTPA or with gentamicin. 99mTc-DTPA deposited in the MS was quantified by image processing method and gentamicin by a fluorescence polarization immunoassay. Ventilation 81mKr images show that the 100 Hz sound increases MS gas ventilation.99mTc-DTPA nebulised in volunteers was mainly deposited into nasal cavities (2/3 vs.1/3 in lungs) with 4.9±2.5% of total nasal deposition in the MS. In the plastinated head model, sonic mode of NL11SN increased the gentamicin deposition in MS by a factor 3 (P

This study examines changes in movement parameters and energy expense during the learning of a cyclical task performed on a “ski simulator”. Five subjects performed five training sessions (each of four 4-minute learning periods separated by a 4-minute rest) and then took a post-test one week later. The instructions were to make movements which were “as wide and frequent as possible”. The subjects were filmed on videotape and their oxygen intake was measured. Movement amplitude, movement frequency, oxygen intake, and a “movement cost” index were calculated. The results indicated a significant increase in movement amplitude and oxygen intake and a decrease in movement cost. The movement frequency of all subjects tended towards the same final value. Two simultaneous changes could occur, with large individual differences: an increase in energy expense due to the increase in the amount of work done, a decrease in energy expense due to the increase in movement economy.

Dans une perspective d’action située, cet article propose une analyse de la cognition et de la culture en action des enseignants. La première partie porte sur les processus d’actualisation et de construction des connaissances dans l’action, la deuxième sur les relations en apparence contradictoires entre le caractère singulier des actions en classe et la possibilité d’une culture partagée, la troisième sur les processus de transmission au sein de cette communauté des pratiques enseignantes., This article presents an analysis of cognition and teachers’ practices. The first part examines actualisation processes and the construction of knowledge; the second describes relationships which appear to be contradictory between the singular character of classroom actions and the possibility of a shared culture; the third describes transmission processes that are at the centre of teachers’ practices., Este artículo propone un análisis de la cognición y de la cultura en acción de los maestros dentro de una perspectiva de acción situada. La primera parte trata de los procesos de actualización y de construcción de los conocimientos en la acción ; la segunda presenta las relaciones aparentemente contradictorias entre el carácter singular de las acciones en clase y la possibilidad de una cultura compartida ; la tercera aborda el proceso de transmisión de las prácticas docentes en el seno de esta., Dieser Artikel stellt eine kognitive Analyse der Kulturvermittlung in Aktion durch die Lehrkräfte dar, und dies im Rahmen eines konkreten Unterrichts-geschehens. Der erste Teil befasst sich mit dem Prozess der Aktualisierung und Konstruktion von Wissen durch Handeln, der zweite mit der auf den ersten Blick widersprüchlichen Beziehung zwischen den spezifischen Aktionsformen in der Klasse und der Möglichkeit einer gemeinsamen Kultur. Der dritte und letzte Teil schließlich befasst sich mit dem Vermittlungs-prozess der Unterrichtsinhalte innerhalb der Klassengemeinschaft.