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Lacquered brass objects are widely present in scientific and technical heritage collections. Localized atmospheric corrosion occurs on the metal when the coating fails to play its protective role. Although lacquered brass objects are not necessarily endangered by this phenomenon, the presence of dark, unpleasant corrosion spots alters the surface appearance, affecting the readability of the objects. Conservators are therefore frequently asked to clean these surfaces. We hereby present the results of a study conducted in the framework of the CleanLaB (Cleaning of Lacquered Brass) project at the Haute Ecole Arc of Neuchâtel for the cleaning of lacquered brass. This work investigates the effects of several gelled cleaning systems applied on artificially aged, lacquered brass samples to remove the corrosion products without affecting the integrity of the coating. The performance of complexing agents commonly used in conservation was compared on lacquered brass mock-ups coated with shellac resin by means of multiple non-invasive characterization and imaging techniques. The tests included conventional complexing agents like sodium citrate and disodium ethylenediaminetetraacetic acid, as well as a bio-originated system based on deferoxamine, a microbial metal chelator investigated as a green alternative in cleaning formulations.

Abstract An innovative green organogel was designed to simultaneously tackle inorganic compounds (i.e., iron corrosion) and organic substances (i.e., acrylic coatings) as undesired materials possibly present on the surface of altered indoor metal artworks. Poly-3-hydroxybutyrate (PHB), ethyl lactate (EL), and deferoxamine B (DFO) were employed in the formulation as thickening agent, organic solvent, and complexing agent, respectively, aiming to propose a sustainable and less harmful chemical cleaning method for metal care. The components were selected because they are bio-sourced, renewable, biodegradable, and non- or low-toxic materials. A multi-modal protocol of analysis was carried out to characterise the newly designed PHB-EL-DFO organogel. The cleaning performance of the novel formulation was assessed on mild steel mock-ups presenting both corrosion and organic coating to be removed. The conducted multi-analytical approach verified that the PHB-EL-DFO gel was able to tackle the two undesired materials simultaneously in an adjustable and easy-to-use way thanks to a modular application.

Summary: Human genetic studies of critical COVID-19 pneumonia have revealed the essential role of type I interferon-dependent innate immunity to SARS-CoV-2 infection. Conversely, an association between the HLA-B∗15:01 allele and asymptomatic SARS-CoV-2 infection in unvaccinated individuals was recently reported, suggesting a contribution of pre-existing T cell-dependent adaptive immunity. We report a lack of association of classical HLA alleles, including HLA-B∗15:01, with pre-omicron asymptomatic SARS-CoV-2 infection in unvaccinated participants in a prospective population-based study in the United States (191 asymptomatic vs. 945 symptomatic COVID-19 cases). Moreover, we found no such association in the international COVID Human Genetic Effort cohort (206 asymptomatic vs. 574 mild or moderate COVID-19 cases and 1,625 severe or critical COVID-19 cases). Finally, in the Human Challenge Characterisation study, the three HLA-B∗15:01 individuals infected with SARS-CoV-2 developed symptoms. As with other acute primary infections studied, no classical HLA alleles favoring an asymptomatic course of SARS-CoV-2 infection were identified.

BackgroundThe exposure to patient suicide (PS) has been identified as one of the most frequent and troubling professional experience for psychiatric trainees. Further studies are needed to better understand how residents cope with these experiences and the association between perceived support and the impacts of PS.MethodIn this qualitative study, we aimed to assess the impact of exposure to PS during psychiatric residency on trainees’ professional career and practical experience. A total of 19 French psychiatric residents participated in 4 focus-groups performed between November 2017 and May 2019.ResultsA total of 4 thematic clusters were identified through a five-step content analysis, namely: (a) reactions to the exposure; (b) coping strategies; (c) professional impact; and (d) prevention and postvention proposals. All participants described the critical impact of the support provided after PS, especially by their senior staff. Those who felt supported by their superior reported less negative impact, both in emotional and professional dimensions. Participants also shared proposals to improve the prevention and postvention issues related to the exposure to PS.ConclusionWe performed the first qualitative study based on focus groups on the impact of PS on psychiatric residents, which allowed for an in-depth understanding of the participants’ lived experiences of the exposure to PS. The narratives inform the need and means to implement prevention and postvention strategies designed to buffer the negative impact of the exposure to PS in psychiatric trainees.

The research study is aimed to design innovative bio-gel formulations able to tackle altered historical metal artworks in a green and sustainable perspective. The target of the research is the removal of undesired or altered materials of both inorganic (i.e., corrosion and tarnishing) and organic nature (i.e., protective coatings). The designed gel systems are initially assessed on mock-ups. Iron-, copper- and silver-based substrates, chosen as mostly present in historical metal collections, are chemically aged to form corrosion on the surface. Alternatively, they are coated with organic protectives (i.e., acrylic and nitrocellulose varnish) that are mostly used for indoor metal care. After multi-modal analytical assessment to check the action and safety of the gels on the metal mock-ups, the developed solutions are applied on real cases, thanks to the strong and fruitful collaboration with curators and conservators of metal artworks.

Among induced mass-mortality events on coral reef, extreme low tides may ultimately lead to considerable reef community deaths on intertidal reef flats due to unusually long and significant aerial exposure. Here, we report an extensive coral mortality event induced by a negative sea level anomaly (nSLA) that occurred across Reunion Island during the austral winter season between June and October 2015 preceding the 2015–2016 El Niño Southern Oscillation (ENSO) event. The nSLA was strong and long in duration with a rapid drop of 35 cm in the mean sea level over a one-month period. Surveys conducted over seven reef flat sites before and after the nSLA revealed that mean coral cover drastically decreased from 54.5 ± 12.7% in early 2015, to 27.4 ± 6.9% in November 2015, which is an equivalent cover loss of 50% following the 2015 nSLA event. The shallowest sites showed a greater decrease in coral cover while the deepest parts of the reef flat remained unaffected. We found a significant correlation between the bathymetry and the relative coral cover variation. Using this relationship between depth and coral cover changes, high-resolution hyperspectral imagery and Lidar bathymetric airborne data, we mapped the impacts of this event at the scale of the whole reef. Overall the modeled loss reached 13.0 ha, which represents a decrease of 45.5% of all live coral cover in this area during the 2015 nSLA event. The impact of a nSLA on emersion times is much greater than the regular variation in tide amplitude between neap and spring tides, reaching new bathymetric ranges that are usually stable in terms of water submersion. Temporal variation of coral cover on Reunion Island reef flat revealed regular decreases to be compared with mean low-water-level events among other sea and climatic related disturbances and stressors.

In the field of cultural heritage, the use of natural gels is rising for the application of active agents. Here, two natural polymers are assessed: agar, a pioneer hydrogel for conservation treatments, and chitosan, a rather novel and metal-binding gel. For chitosan, a state-of-the-art based formulation (CS–ItA–LCys) is evaluated as it was reported for silver-complexing properties. It is evaluated whether these polymers can withstand the addition of the chelating compound deferoxamine, which is a bacterial siderophore. This allows for the obtainment of completely bio-sourced gel systems. A Fourier-transformed (FT) infrared spectroscopy characterization is performed, completed with rheological measurements and Cryo-Scanning Electron Microscopy (cryo–SEM) to investigate the physico–chemical properties of the gels, as well as their interaction with deferoxamine. Both polymers are also tested for their inherent complexing ability on silver ions using FT–Raman spectroscopy. A multi-analytical comparison shows different microstructures, in particular, the presence of a thick membrane for chitosan and different mechanical behaviors, with agar being more brittle. Neither hydrogel seems affected by the addition of deferoxamine; this is shown by similar rheological behavior and molecular structures in the presence or absence of the chelator. The intrinsic abilities of the chitosan formulation to make silver complex are demonstrated with the observation of two peaks characteristic of Ag–S and Ag–O bonds. Agar and chitosan are both proven to be reliable gels to act as carriers for bio-based active agents. This paper confirms the potential asset of the chitosan formulation CS–ItA–LCys as a promising gel for the complexation of soluble silver.

A series of seven novel iridium complexes were synthetized and characterized as potential photosensitizers for photodynamic therapy (PDT) applications. Among them, four complexes were evaluated in vitro for their anti-proliferative activity with and without irradiation on a panel of five cancer cell lines, namely PC-3 (prostate cancer), T24 (bladder cancer), MCF7 (breast cancer), A549 (lung cancer) and HeLa (cervix cancer), and two non-cancerous cell models (NIH-3T3 fibroblasts and MC3T3 osteoblasts). After irradiation at 458 nm, all tested complexes showed a strong selectivity against cancer cells, with a selectivity index (SI) ranging from 8 to 34 compared with non-cancerous cells. The cytotoxic effect of all these complexes was found to be independent of the anti-apoptotic protein Bcl-xL. The compound exhibiting the best selectivity, complex 4a, was selected for further investigations. Complex 4a was mainly localized in the mitochondria. We found that the loss of cell viability and the decrease in ATP and GSH content induced by complex 4a were independent of both Bcl-xL and caspase activation, leading to a non-apoptotic cell death. By counteracting the intrinsic or acquired resistance to apoptosis associated with cancer, complex 4a could be an interesting therapeutic alternative to be studied in preclinical models.

Single-item scales are widely used in the field of user experience to report the emotions. However, they are strongly criticized and discouraged by the scientific community. While they have several practical advantages, single-item scales are mainly criticized for their psychometric weakness. Our research explores to what extent single-item scales reflect what a user has experienced during his or her interaction with technology, overall, but also at specific moments such as first and last impressions. This research also explores the sensitivity of these measures across different contexts of use brought by the presence or absence of certain interface features. We conducted a correlational study with 40 users while interacting with financial institution websites. We used two methods to evaluate the experience: lived and measured implicitly using psychophysiological instruments on one hand and self-perceived and measured using single-item scales, on the other hand. Overall, our results suggest limited correlations and in most cases contradictory between lived and perceived experience. We conclude by highlighting the limits to be taken into account when professionals are led to use single-item scales.

The symbiotic shrimp Rimicaris exoculata dominates the macrofauna inhabiting the active smokers of the deep-sea mid Atlantic ridge vent fields. We investigated the nature of the host mechanisms controlling the vital and highly specialized ectosymbiotic community confined into its cephalothoracic cavity. R. exoculata belongs to the Pleocyemata, crustacean brooding eggs, usually producing Type I crustins. Unexpectedly, a novel anti-Gram-positive type II crustin was molecularly identified in R. exoculata. Re-crustin is mainly produced by the appendages and the inner surfaces of the cephalothoracic cavity, embedding target epibionts. Symbiosis acquisition and regulating mechanisms are still poorly understood. Yet, symbiotic communities were identified at different steps of the life cycle such as brooding stage, juvenile recruitment and molt cycle, all of which may be crucial for symbiotic acquisition and control. Here, we show a spatio-temporal correlation between the production of Re-crustin and the main ectosymbiosis-related life-cycle events. Overall, our results highlight (i) a novel and unusual AMP sequence from an extremophile organism and (ii) the potential role of AMPs in the establishment of vital ectosymbiosis along the life cycle of deep-sea invertebrates.

BackgroundExposure to patient or user suicide (PUS) is identified as a challenging occupational hazard for mental health and social work professionals. Professionals exposed to PUS may encounter several ranges of emotional, traumatic or professional impacts in the aftermath. A high proportion of exposed professionals reports a lack of support in the aftermath of PUS. SUPPORT is a postvention program designed to provide a comprehensive, adaptative and effective support to professionals impacted by PUS. The aims of the SUPPORT-S study are to (1) improve the design of the SUPPORT program, (2) evaluate the effectiveness of the program to buffer the emotional, traumatic and professional impacts and to improve the perceived social support for professionals exposed to PUS, and (3) provide more insights into the consequences of PUS on both professionals and organizations.MethodThe SUPPORT-S study is a mixed method collaborative and participatory action research. The simultaneous and complementary collection and analysis of qualitative and quantitative data will offer an in-depth evaluation of the implementation and the effectiveness of the program. The qualitative evaluation includes: (a) an ethnographic observation; (b) 25 semi-directed interviews with randomized participants; (c) an activity analysis with providers of the program; and (d) collaborative sharing of the results with providers and participants. The quantitative evaluation includes pre- and post-measures in participants of: (a) emotional impact (Differential Emotions Scale IV); (b) traumatic impact (Impact of Event Scale-Revised); (c) professional impact (non-validated questionnaire); and (d) perceived social support (Perceived Social Support Scale for Professionals). The action research design will rely on: (a) the cycling process of implementation/evaluation/data sharing/adjustment and (b) the participatory approach through data sharing with providers and participants. Triangulation, saturation, randomization, and participatory design will also reduce the risk of biases and will improve the generalizability of conclusions.Expected ResultsWe expect the SUPPORT-S study to evaluate and improve the design of the SUPPORT program to effectively help professionals to cope with PUS.ConclusionThe results of the study will allow us to disseminate an effective and adaptive postvention program for professionals and institutions encountering PUS.

Abstract Background Alzheimer’s disease (AD) is characterized by the accumulation of β-amyloid (Aβ) peptides and hyperphosphorylated tau protein accompanied by neuronal loss. Aβ accumulation has been associated with an impaired sphingosine 1-phosphate (S1P) metabolism. S1P is generated by sphingosine kinases (SphKs), of which there are two isoenzymes SphK1 and SphK2, and degraded by the sphingosine 1-phosphate lyase (SPL). We previously reported, that both a decrease in SphK1 expression and an increase in SPL expression, correlated with amyloid deposits in the entorhinal cortex of AD brains, suggesting a global loss of pro-survival S1P in AD neurons. SphK2 contribution has also been examined in AD yielding to conflicting results that may reflect the complexity of SphK2 regulation. The subcellular localization of SphK2, hence the compartmentalization of generated S1P, is recognized to play a crucial role in dictating either its pro-survival or pro-apoptotic functions. We therefore aimed at studying the expression of SphK2 and notably its subcellular localization in brain tissues from patients with AD. Results We report that a decrease in SphK2 protein cytosolic expression correlated with the density of amyloid deposits in a cohort of 25 post-mortem brains. Interestingly, we observed that the equilibrium between cytoplasmic and nuclear SphK2 is disrupted and showed that SphK2 is preferentially localized in the nucleus in AD brain extracts as compared to control extracts, with a marked increase of cleaved SphK2. Conclusions Our results suggest that a shift in the subcellular localization of the S1P generating SphK2 may compromise the well established pro-survival cytosolic S1P by favoring the production of nuclear S1P associated with adverse effects in AD pathogenesis.

Although sphingosine-1-phosphate receptor 1 (S1P1) has been shown to trigger several S1P targeted functions such as immune cell trafficking, cell proliferation, migration, or angiogenesis, tools that allow the accurate detection of endogenous S1P1 localization and trafficking remain to be obtained and validated. In this study, we developed and characterized a novel monoclonal S1P1 antibody. Mice were immunized with S1P1 produced in the yeast Pichia pastoris and nine hybridoma clones producing monoclonal antibodies were created. Using different technical approaches including Western blot, immunoprecipitation and immunocytochemistry, we show that a selected clone, hereinafter referred to as 2B9, recognizes human and mouse S1P1 in various cell lineages. The interaction between 2B9 and S1P1 is specific over receptor subtypes, as the antibody does not binds to S1P2 or S1P5 receptors. Using cell-imaging methods, we demonstrate that 2B9 binds to an epitope located at the intracellular domain of S1P1; reveals cytosolic and membrane localization of the endogenous S1P1; and receptor internalization upon S1P or FTY720-P stimulation. Finally, loss of 2B9 signal upon knockdown of endogenous S1P1 by specific small interference RNAs further confirms its specificity. 2B9 was also able to detect S1P1 in human kidney and spinal cord tissue by immunohistochemistry. Altogether, our results suggest that 2B9 could be a useful tool to detect, quantify or localize low amounts of endogenous S1P1 in various physiological and pathological processes.

In the general global rise of attention and research to seek greener attitudes, the field of cultural heritage (CH) makes no exception. In the last decades, an increasing number of sustainable and biologically based solutions have been proposed for the protection and care of artworks. Additionally, the safety of the target artwork and the operator must be kept as core goals. Within this scenario, new products and treatments should be explored and implemented in the common conservation praxes. Therefore, this review addressing metal heritage is aimed to report biologically derived gel formulations already proposed for this specific area as reliable tools for cleaning. Promising bio-gel-based protocols, still to be implemented in metal conservation, are also presented to promote their investigation by stakeholders in metal conservation. After an opening overview on the common practices for cleaning metallic surfaces in CH, the focus will be moved onto the potentialities of gel-alternatives and in particular of ones with a biological origin. In more detail, we displayed water-gels (i.e., hydrogels) and solvent-gels (i.e., organogels) together with particular attention to bio-solvents. The discussion is closed in light of the state-of-the-art and future perspectives.

The present study focuses on a detailed structural investigation at atomic scale of the planar defects that appear in the olivine grains in the Allende meteorite, and it aims to clarify their nature and the related formation mechanism. The investigation was performed using advanced spectro-microscopy techniques such as atomically resolved high-angle annular dark field (HAADF) images coupled with electron energy loss spectroscopy in the scanning transmission electron microscopy mode (STEM-EELS). Two prominent structural features appear in the investigated olivine grains: (i) Exsolution platelets with a thickness between 2 and 10 nm with the spinel structure and chemical composition expressed as a solid solution between magnetite, chromite, and MgAl2O4. (ii) Thinner planar defects appeared with thickness between 2 to 4 atomic planes, which were rich in Fe and had a strong Fe3+ contribution. The structure of these defects was described by the crystalline lattice of the olivine grains with small distortion of the measured cationic distances, which can be related to Fe3+-Si substitution in the tetrahedral sites. Those metastable defects should have preceded the formation of the thicker spinel exsolutions and could have formed during an oxidizing event in the Allende parent body.

Falling is the main cause of domestic accidents and fatal injuries to seniors at home. In this paper, we describe the design process for a new pervasive technology (CIRDO). The aim of this technology is to detect falls (via audio and video sensors) and to alert the elderly's family or caregivers. Two complementary studies were performed. Firstly, the actual risk situations of older adults were analyzed. Secondly, social acceptance was investigated for the different homecare field stakeholders. Our results highlight the tensions among social actors towards the tool and their impacts on technology acceptance by the elderly. Also, we show a significant change in the fall process due to the device. In actuality, the social functions associated with CIRDO implementation and the necessity of iterative design processes suggest that the CIRDO system should be more flexible and versatile to better fit the risk behaviors of seniors that evolve using this device.

The purpose of this paper is to propose a functional and diachronic taxonomy of the different simulation types that the study day, devoted to the simulation process (organized by the Review “Activities”), made it possible to highlight. This categorization is based on four main orientations of the staging of the activity that can relate respectively to the simulation of a situation (i) to come (prospective or predictive simulation), (ii) to become (constructive or reflexive simulation), (iii) alive or persistent (projective simulation) and (iv) past (retrospective simulation). For each of these approaches, we will outline the main associated methods and discuss their respective contributions and limitations.

Tinnitus masking and residual inhibition (RI) are two well-known psychoacoustic measures of tinnitus. While it has long been suggested that they may provide diagnostic and prognostic information, these measures are still rarely performed in clinics, as they are too time consuming. Given this issue, the main goal of the present study was to validate a new method for assessing these measures. An acoustic sequence made of pulsed stimuli, which included a fixed stimulus duration and interstimulus interval, was applied to 68 tinnitus patients at two testing sites. First, the minimum masking level (MML) was measured by raising the stimulus intensity until the tinnitus was unheard during the stimulus presentation. Second, the level of the stimulus was further increased until the tinnitus was suppressed during the silence interval between the acoustic pulses. This level was called the minimum residual inhibition level (MRIL). The sequential measurement of MML and MRIL from the same stimulus condition offers several advantages such as time efficiency and the ability to compare results between the MRIL and MML. Our study confirms that, from this new approach, MML and MRIL can be easily and quickly obtained from a wide variety of patients displaying either normal hearing or different hearing loss configurations. Indeed, MML was obtained in all patients except one (98.5%), and some level of MRIL was found on 59 patients (86.7%). More so, this approach allows the categorization of tinnitus patients into different subgroups based on the properties of their MRIL.

The scientific literature points to an individualization of psychological health issues at work that is hindering efficient prevention. Using a mixed method, we sought to verify whether people in organizations noticed the described trend in the individualization of health issues. A survey was conducted with 137 people (staff representatives and managers) about the importance they attributed to six factors that influenced the emergence of psychosocial risks. The results showed that the perceived weight of the “personal difficulties” factor was significantly lower than those of “work pressure” and “internal group issues.” The individual perception of factors influencing psychosocial risks therefore seems to be driven more by “working condition challenges” than “personal challenges.” The collective interviews furthermore showed how social relations impacted organizational practices.

Understanding the conditions for the integration of ICT into the professional activity of older workers is an important social issue. In this article based on the study of the activity of rail traffic officers, we propose to apprehend the psychosocial resources that these workers mobilize in order to cope with and adapt to new technological working environments. This research draws on the theoretical foundations developed around both a developmental and systemic approach to activity, such as that provided by the activity system (Engeström, 1987). We seek to understand the relationships between older workers and ICTs but also to understand how they build and develop their professional practices in real working situations, both by and with technological devices, but also in interaction with their colleagues. It is about taking into account the socio-technical environment in which older workers evolve. Data collection was carried out using a process of methodological triangulation in order to understand six rail traffic officers’ mediated activities in two different stations. The results reveal that there is no difference in the use and acceptance of technical devices between younger and older officers, although the logic and/or strategies of use differ. In this way, we identified various ways of doing the job, which were created on a collective basis and which would appear to be elements that influence the development of the activity mediated by the technological tools available to traffic officers.

Improving the visibility of art(ists) is an essential activity which could be mediated by Social Networks Sites (SNS). However, SNS represent both a resource and a constraint for artists. We therefore argue that it is not a straightforward process for artists to accept these technologies. The aim of this study is to identify factors facilitating or impeding the acceptance of SNS by artists. The theoretical framework supporting this research is the situated technology acceptance model (Bobillier Chaumon, 2013). This model proposes to analyse the acceptance of technology through personal, interpersonal, metapersonal and transpersonal dimensions. We conducted a qualitative research with both traditional and digital artists. The method was based on 12 semi-structured interviews and 4 interviews for explanatory purposes. The results highlight the influence of attitudes to new technologies and the consistency between technologies and artistic direction on the SNS acceptance process. Factors facilitating SNS acceptance mainly embody interpersonal and personal dimensions. Transpersonal, metapersonal and personal dimensions comprise negative factors which can lead to a rejection of SNS. We identify 4 types of regulation strategy to cope with negative factors. Among these strategies, we discuss the utility of narrative strategies for the development of both SNS acceptance and artist development.

In recent years, the diagnostic and therapeutic uses of radioisotopes have shown significant progress. Immunoglobulin (Ig) appears to be a promising tracer, particularly due to its ability to target selected antigens. The main objective of this study is to optimize and assess an Ig radiolabeling method with Technetium 99m (99mTc), an attractive radioelement used widely for diagnostic imaging. Monoclonal anti-CD20 IgG was retained to study in vitro and in vivo radiolabeling impact. After IgG derivatization with 2-iminothiolane, IgG-SH was radiolabeled by an indirect method, using a 99mTc-tricarbonyl core. Radiolabeling stability was evaluated over 24h by thin-layer chromatography. IgG integrity was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis coupled with Western blot and autoradiography. The radiolabeled Ig's immunoaffinity was assessed in vitro by a radioimmunoassay method and binding experiments with cells (EL4-hCD20 and EL4-WT). Biodistribution studies were performed in normal BALB/c mice. Tumor uptake was assessed in mice bearing EL4-hCD20 and EL4-WT subcutaneous xenografts. With optimized method, high radiolabeling yields were obtained (95.9 ± 3.5%). 99mTc-IgG-SH was stable in phosphate-buffered saline (4°C and 25°C) and in serum (37°C), even if important sensitivity to transchelation was observed. IgG was not degraded by derivatization and radiolabeling, as shown by Western blot and autoradiography results. 99mTc-anti-CD20 IgG-SH immunoaffinity was estimated with Kd = 35 nM by both methods. In vivo biodistribution studies for 48h showed significant accumulation of radioactivity in plasma, liver, spleen, lungs and kidneys. Planar scintigraphy of mice bearing tumors showed a significant uptake of 99mTc-anti-CD20 IgG-SH in CD20+ tumor versus CD20- tumor. Radiolabeling of derivatized IgG with 99mTc-tricarbonyl was effective, stable and required few antibody amounts. This attractive radiolabeling method is "antibody safe" and preserves Ig affinity for antigen, as shown by both in vitro and in vivo experiments. This method could easily be used with noncommercial IgG or other antibody isotypes.

We examine the case of forestry and show the reality of multigenerational forest management. This activity takes two forms: that of distributed work and that of cooperative longitudinal activity. In the case of distributed work, foresters apply working rules, which may or may not be explicit, collectively developed by and throughout History. In the case of cooperative activity, foresters use their knowledge of how the forest functions to optimize the future working situation and thus facilitate the work of their successors. In this case, cooperative work is based on a pragmatic and shared conception of a trajectory. This conception is developed through a form of controversy shaped by historical documents which have become intermediary objects.

The emblematic hydrothermal worm Alvinella pompejana is one of the most thermo tolerant animal known on Earth. It relies on a symbiotic association offering a unique opportunity to discover biochemical adaptations that allow animals to thrive in such a hostile habitat. Here, by studying the Pompeii worm, we report on the discovery of the first antibiotic peptide from a deep-sea organism, namely alvinellacin. After purification and peptide sequencing, both the gene and the peptide tertiary structures were elucidated. As epibionts are not cultivated so far and because of lethal decompression effects upon Alvinella sampling, we developed shipboard biological assays to demonstrate that in addition to act in the first line of defense against microbial invasion, alvinellacin shapes and controls the worm's epibiotic microflora. Our results provide insights into the nature of an abyssal antimicrobial peptide (AMP) and into the manner in which an extremophile eukaryote uses it to interact with the particular microbial community of the hydrothermal vent ecosystem. Unlike earlier studies done on hydrothermal vents that all focused on the microbial side of the symbiosis, our work gives a view of this interaction from the host side.

In order to address the questions raised by a new railway line crossing the Rhône, and in addition to mathematical modelling conducted during the preliminary studies, SNCF Réseau commissioned Artelia Eau & Environnement with a physical scale model study of the projected infrastructure. The physical scale model represented the river Rhône and its flood plain, the existing bridges over the river Rhône for the A432 motorway and the high speed line, and then the project (viaduct and relief structures). After calibration of the measurements devices, tests were carried out in current conditions, in design conditions and in optimised design conditions. The physical scale model enabled to identify the hydraulic impact of the project during flood events (increase of the maximum water level, due to bad flow conditions at the inlet of relief structures) and validate the improvements of the design (reshaping of the relief structures’ inlet, and removal of embankments close to the relief structures). The final optimized design ensures the hydraulic transparency of the project.

Background While most antibody-based therapies use IgG because of their well-known biological properties, some functional limitations of these antibodies call for the development of derivatives with other therapeutic functions. Although less abundant than IgG in serum, IgA is the most abundantly produced Ig class in humans. Besides the specific targeting of its dimeric form to mucosal areas, IgA was shown to recruit polymorphonuclear neutrophils against certain targets more efficiently than does IgG1.Design and Methods In this study, we investigated the various pathways by which anti-tumor effects can be mediated by anti-CD20 IgA against lymphoma cells.Results We found that polymeric human IgA was significantly more effective than human IgG1 in mediating direct killing or growth inhibition of target cells in the absence of complement. We also demonstrated that this direct killing was able to indirectly induce the classical pathway of the complement cascade although to a lesser extent than direct recruitment of complement by IgG. Recruitment of the alternative complement pathway by specific IgA was also observed. In addition to activating complement for lysis of lymphoma cell lines or primary cells from patients with lymphoma, we showed that monomeric anti-CD20 IgA can effectively protect mice against tumor development in a passive immunization strategy and we demonstrated that this protective effect may be enhanced in mice expressing the human FcαRI receptor on their neutrophils.Conclusions We show that anti-CD20 IgA antibodies have original therapeutic properties against lymphoma cells, with strong direct effects, ability to recruit neutrophils for cell cytotoxicity and even recruitment of complement, although largely through an indirect way.

Activation of an acid sphingomyelinase (aSMase) leading to a biosynthesis of GD3 disialoganglioside has been associated with Fas-induced apoptosis of lymphoid cells. The present study was undertaken to clarify the role of this enzyme in the generation of gangliosides during apoptosis triggered by Fas ligation. The issue was addressed by using aSMase-deficient and aSMase-corrected cell lines derived from Niemann-Pick disease (NPD) patients. Fas cross-linking elicited a rapid production of large amounts of complex a- and b-series species of gangliosides with a pattern and a chromatographic behavior as single bands reminiscent of brain gangliosides. The gangliosides were synthesized within the first ten minutes and completely disappeared within thirty minutes after stimulation. Noteworthy is the observation that GD3 was not the only ganglioside produced. The production of gangliosides and the onset of apoptotic hallmarks occurred similarly in both aSMase-deficient and aSMase-corrected NPD lymphoid cells, indicating that aSMase activation is not accountable for ganglioside generation. Hampering ganglioside production by inhibiting the key enzyme glucosylceramide synthase did not abrogate the apoptotic process. In addition, GM3 synthase-deficient lymphoid cells underwent Fas-induced apoptosis, suggesting that gangliosides are unlikely to play an indispensable role in transducing Fas-induced apoptosis of lymphoid cells.

The accreditation of work experience introduces a rift between training and qualification. The fact that qualification can be acquired without undergoing training raises the sensitive issue of how experience should be assessed. As part of the trend towards conceptualizing actions, our study focuses on acquiring a better understanding of the experience of computer specialists applying for work experience accreditation by asking them to perform a specific modelling task. Our analysis involved exposing the conceptual structure of the situation, i.e. all the dimensions of the task that should be considered in order for the action to be effective. This structure is rooted in the following three aspects: (1) Mastery of a language, (2) Use of that language in a process of more or less extensive conceptualization, (3) Adjusting the conceptualization according to whether it is aimed chiefly at a colleague, a user or a researcher. Using this conceptual position, we have drawn six profiles of computer specialists using different operative models.

Apresenta-se pela primeira vez na literatura mundial uma avaliaçao do acompanhamento de pacientes que receberam implante de cardiodesfibriladores na América Latina (ICD Registry - Medtronic Latin America). O registro é de vital importância para orientar condutas em cardiopatias de diferentes etiologias, tais como doença de Chagas, miocardiopatia dilatada idiopática e coronariopatias. As informaçoes sao específicas de um grupo de 910 pacientes que compoem o banco de dados deste estudo multicêntrico. A ênfase recai nos aspectos demográficos, uma vez que o estudo refere-se a países com realidades muito distintas e em que há importantes variaçoes etiológicas. A análise de uma série de parâmetros poderá servir de orientaçao para aqueles que trabalham na área, além de proporcionar a análise estatística entre os tipos de prevençao (primária e secundária) para diferentes etiologias, seguindo um protocolo rigoroso e estabelecido previamente.

BACKGROUND: Sphingosine kinase-1 (SphK1) is an oncogenic lipid kinase notably involved in response to anticancer therapies in prostate cancer. Androgens regulate prostate cancer cell proliferation, and androgen deprivation therapy is the standard of care in the management of patients with advanced disease. Here, we explored the role of SphK1 in the regulation of androgen-dependent prostate cancer cell growth and survival. METHODOLOGY/PRINCIPAL FINDINGS: Short-term androgen removal induced a rapid and transient SphK1 inhibition associated with a reduced cell growth in vitro and in vivo, an event that was not observed in the hormono-insensitive PC-3 cells. Supporting the critical role of SphK1 inhibition in the rapid effect of androgen depletion, its overexpression could impair the cell growth decrease. Similarly, the addition of dihydrotestosterone (DHT) to androgen-deprived LNCaP cells re-established cell proliferation, through an androgen receptor/PI3K/Akt dependent stimulation of SphK1, and inhibition of SphK1 could markedly impede the effects of DHT. Conversely, long-term removal of androgen support in LNCaP and C4-2B cells resulted in a progressive increase in SphK1 expression and activity throughout the progression to androgen-independence state, which was characterized by the acquisition of a neuroendocrine (NE)-like cell phenotype. Importantly, inhibition of the PI3K/Akt pathway--by negatively impacting SphK1 activity--could prevent NE differentiation in both cell models, an event that could be mimicked by SphK1 inhibitors. Fascinatingly, the reversability of the NE phenotype by exposure to normal medium was linked with a pronounced inhibition of SphK1 activity. CONCLUSIONS/SIGNIFICANCE: We report the first evidence that androgen deprivation induces a differential effect on SphK1 activity in hormone-sensitive prostate cancer cell models. These results also suggest that SphK1 activation upon chronic androgen deprivation may serve as a compensatory mechanism allowing prostate cancer cells to survive in androgen-depleted environment, giving support to its inhibition as a potential therapeutic strategy to delay/prevent the transition to androgen-independent prostate cancer.