23 research outputs found
A multi-faceted framework of diversity for prioritizing the conservation of fish assemblages
Floodplain waterbodies and their biodiversity are increasingly threatened by human activities. Given the limited resources available to protect them, methods to identify the most valuable areas for biodiversity conservation are urgently needed. In this study, we used freshwater fish assemblages in floodplainwaterbodies to propose an innovative method for selecting priority areas based on four aspects of their diversity: taxonomic (i.e. according to species classification), functional (i.e. relationship between speciesand ecosystem processes), natural heritage (i.e. species threat level), and socio-economic (i.e. species interest to anglers and fishermen) diversity. To quantitatively evaluate those aspects, we selected nine indices derived either from metrics computed at the species level and then combined for each assemblage (species rarity, origin, biodiversity conservation concern, functional uniqueness, functional originality, fishing interest), or from metrics directly computed at the assemblage level (species richness, assemblage rarity, diversity of biological traits). Each of these indices belongs to one of the four aspects of diversity. A synthetic index defined as the sum of the standardized aspects of diversity was used to assess the multifaceted diversity of fish assemblages. We also investigated whether the two main environmental gradients at the catchment (distance from the sea) and at the floodplain (lateral connectivity of the waterbodies) scales influenced the diversity of fish assemblages, and consequently their potential conservation value. Finally, we propose that the floodplain waterbodies that should be conserved as a priority are those located in the downstream part of the catchment and which have a substantial lateral connectivity with the main channel
Multistress effects on goldfish (Carassius auratus) behavior and metabolism
Crossed effects between climate change and chemical pollutions were identified on community structure and ecosystem functioning. Temperature rising affects the toxic properties of pollutants and the sensitiveness of organisms to chemicals stress. Inversely, chemical exposure may decrease the capacity of organisms to respond to environmental changes. The aim of our study was to assess the individual and crossed effects of temperature rising and pesticide contamination on fish. Goldfish, Carassius auratus, were exposed during 96 h at two temperatures (22 and 32 °C) to a mixture of common pesticides (S-metolachlor, isoproturon, linuron, atrazine- desethyl, aclonifen, pendimethalin, and tebuconazol) at two environmentally relevant concentrations (total concentrations MIX1=8.4 ÎŒg Lâ1 and MIX2=42 ÎŒg Lâ1). We investigated the sediment reworking behavior, which has a major ecological functional role. We also focused on three physiological traits from the cellular up to the whole individual level showing metabolic status of fish (protein concentration in liver and muscle, hepatosomatic index, and Fultonâs condition factor). Individual thermal stress and low concentrations of pesticides decreased the sediment reworking activity of fish and entrained metabolic compensation with global depletion in energy stores. We found that combined chemical and thermal stresses impaired the capacity of fish to set up an efficient adaptive response. Our results strongly suggest that temperature will make fish more sensitive to water contamination by pesticides, raising concerns about wild fish conservation submitted to global changes
A cost-effective method to quantify biological surface sediment reworking
We propose a simple and inexpensive method to determine the rate and pattern of surface sediment reworking by benthic organisms. Unlike many existing methods commonly used in bioturbation studies, which usually require sediment sampling, our approach is fully non-destructive and is well suited for investigating non-cohesive fine sediments in streams and rivers. Optical tracer (e.g., luminophores or coloured sand) disappearance or appearance is assessed through time based on optical quantification of surfaces occupied by tracers. Data are used to calculate surface sediment reworking (SSR) coefficients depicting bioturbation intensities. Using this method, we evaluated reworking activity of stream organisms (three benthic invertebrates and a fish) in laboratory microcosms mimicking pool habitats or directly in the field within arenas set in depositional zones. Our method was sensitive enough to measure SSR as low as 0.2 cm2.d-1, such as triggered by intermediate density (774 m-2) of Gammarus fossarum (Amphipoda) in microcosms. In contrast, complex invertebrate community in the field and a fish (Barbatula barabatula) in laboratory microcosms were found to yield to excessively high SSR (>60 cm2.d-1). Lastly, we suggest that images acquired during experiments can be used for qualitative evaluation of species-specific effects on sediment distribution
L'ergotoxicologie en actions â Mobiliser l'analyse de l'activitĂ© pour rĂ©duire les risques chimiques
Contexte et objectifs Lâergotoxicologie est conçue comme une pratique particuliĂšre de lâergonomie (Garrigou, 2011) visant Ă analyser les activitĂ©s de travail dans des milieux professionnels oĂč des expositions Ă des produits chimiques peuvent se produire. Dans ce cadre, lâergotoxicologie dĂ©veloppe « des modĂšles opĂ©rants (au sens de Wisner, 1972), des outils et des moyens de prĂ©vention efficaces pour gĂ©rer et prĂ©venir les risques pour la santĂ© des travailleurs exposĂ©s Ă des produits chimiques » (Garrigou, 2011). En ce sens, il sâagit bien dâune forme de recherche et de pratique Ă visĂ©e opĂ©rationnelle, et non dâune nouvelle discipline ou sous-discipline de lâergonomie. On peut alors considĂ©rer que lâergotoxicologie est un des domaines de spĂ©cialisation de lâergonomie (Falzon, 2004, p.18). Dans cette perspective lâergotoxicologie est ancrĂ©e profondĂ©ment dans lâergonomie, mais de par ses objectifs, elle mobilise des connaissances et des modĂšles issus de la toxicologie, de la mĂ©decine du travail et de la prĂ©vention. Sa pratique nĂ©cessite donc un engagement transdisciplinaire, en ne perdant pas de vue que ses racines se nourrissent de lâanalyse de lâactivitĂ© (Garrigou, 2011). Lâergotoxicologie se dĂ©veloppe dans un contexte de remise en question des pratiques classiques de prĂ©vention des risques liĂ©s Ă lâutilisation de produits chimiques dĂ©taillĂ© par Mohammed-Brahim & Garrigou (2009). La notion dâergotoxicologie est apparue Ă partir de la nĂ©cessitĂ© de prendre en compte les caractĂ©ristiques rĂ©elles des opĂ©rateurs exposĂ©s en situations de travail pouvant influencer les effets sur la santĂ© ou en raison dâune non certitude dâabsence dâeffets sur la santĂ© malgrĂ© le respect des normes Ă©tablies (Villate, 1985). Ces « bonnes pratiques » actuelles de prĂ©vention sont essentiellement basĂ©es sur la mise en place de barriĂšres entre une source de danger (NPs par exemple) et les opĂ©rateurs, comme dĂ©crit par Mortureux (2016). La principale limite de ce modĂšle et de son opĂ©rationnalisation (Mohammed-Brahim & Garrigou, 2009) est lâefficacitĂ© partielle de ces barriĂšres pouvant ĂȘtre « permĂ©ables ». La mise en place des barriĂšres ne rĂ©sulte pas toujours dâune analyse systĂ©mique des situations Ă risque, les causes rĂ©elles dĂ©terminantes des expositions peuvent ĂȘtre ainsi occultĂ©es. Une telle reprĂ©sentation des actions possibles sâinterdit alors dâagir sur les dĂ©terminants rĂ©els de lâexposition, en raison dâun manque de prise en compte de lâactivitĂ© de travail, au profit dâune prise en compte de la tĂąche prescrite. Les normes Ă©tablies dans ces modĂšles classiques de prĂ©vention sont ainsi souvent dĂ©contextualisĂ©es des situations de travail et de lâactivitĂ© rĂ©elle (Galey & Garrigou., 2020). Ces derniĂšres annĂ©es, lâergotoxicologie a fait lâobjet de nombreux dĂ©veloppements conceptuels et mĂ©thodologiques par la construction de projets de recherche-intervention financĂ©s dans le cadre de rĂ©ponses Ă des appels Ă projets de recherche de publics. On peut citer les travaux de Judon (2017) portant sur les expositions au fumĂ©es de bitume des travailleurs de la route. Ceux de Galey (2019) sur la caractĂ©risation des expositions aux particules nanomĂ©triques dans les nouveaux procĂ©dĂ©s industriels comme la fabrication additive. Ainsi que les travaux de Jolly (Jolly et al., 2021) sur lâexposition des pomiculteurs quĂ©bĂ©cois aux pesticides, de Goutille (Goutille et al., 2016 ; Goutille & Garrigou, 2021 ; Goutille, 2022) sur la co-construction de la prĂ©vention des risques en milieux industriels et agricoles, ou bien les travaux dâAlbert (Albert et al., 2021) sur lâarticulation des sources du droit et de lâergonomie pour concevoir autrement les pulvĂ©risateurs, Lâobjectif de ce symposium est de contribuer Ă la transmission/traduction de ces concepts et mĂ©thodologies pour engager des actions de transformations. En effet, aujourdâhui, lâergotoxicologie nâest pas rĂ©servĂ©e aux seuls ergonomes. Elle est Ă©galement mobilisĂ©e par des prĂ©venteurs internes ou en service de santĂ© au travail et par des toxicologues (Mohammed-Brahim et al., 2018), nourrissant une pratique transprofessionnelle. Axes de rĂ©flexion Le premier axe de rĂ©flexion concerne la transmission des concepts et des mĂ©thodes dĂ©veloppĂ©s en ergotoxicologie et leur traduction et ou leur transformation dans des contextes dâintervention divers (entreprises, services de santĂ© au travail, etc.) et dans des logiques mĂ©tiers diffĂ©rentes (ergonomes, prĂ©venteurs, toxicologues, mĂ©decin du travailâŠ). Le deuxiĂšme axe va porter sur la possibilitĂ© des acteurs mettant en oeuvre des concepts et mĂ©thodes issus de lâergotoxicologie de pouvoir ou pas dĂ©velopper des approches pluridisciplinaires et/ou transprofessionnelles dans leurs actions de construction des problĂšmes, de diagnostics mais aussi de co-construction des transformations de la situation de travail. Cette problĂ©matique va porter sur les interactions entre les « experts » de la prĂ©vention mais aussi sur lâimplication du chef dâentreprise, des salariĂ©s et de leurs reprĂ©sentants. Le troisiĂšme axe portera sur les dĂ©terminants des expositions qui font lâobjet de la construction du problĂšme, des analyses, et des transformations. Nous nous intĂ©resserons aux diffĂ©rents dĂ©terminants de lâexposition prĂ©sents dans la situation de travail, quâils soient dâordre technique, humain ou organisationnels. Lâobjectif de la discussion est aussi dâaller discuter de familles de dĂ©terminants qualifiĂ©s dâĂ©loignĂ©s de la situation de travail mais qui concourent aux expositions. Ce symposium s'appuiera sur 5 prĂ©sentations et un dĂ©bat avec les participants autour des questions que pose la prĂ©vention durable du risque chimique en milieu de travail. Les communicants dâorigine disciplinaire et professionnelle diverse (doctorants, prĂ©venteurs, consultant, service SST, anthropologue, ergonome, toxicologue, âŠ) prĂ©senteront leurs travaux de recherche et dâintervention en milieu hospitalier, agricole, dans le BTP, ainsi que dans des plus petites entreprises (TPE et cabinet de podologie). La premiĂšre contribution sera prĂ©sentĂ©e par CĂ©dric Gouvenelle (ergonome) et Julie Vornax (toxicologue) de lâASPT 18. Elle portera sur lâapport de lâergotoxicologie en service de santĂ© au travail. Dans le cadre de cette Ă©tude prĂ©sentĂ©e, la fabrication dâĂ©lĂ©ments en bĂ©ton est identifiĂ©e par le mĂ©decin du travail comme un secteur exposant les travailleurs Ă de la silice cristalline cancĂ©rogĂšne (ANSES, 2019. Le mĂ©decin du travail identifie ces formes dâexposition lors de lâĂ©tablissement du diagnostic santĂ© travail en sâappuyant sur les donnĂ©es des visites des travailleurs, la dĂ©claration des risques de l!employeurs et la littĂ©rature. Dans un contexte oĂč les perceptions entre les travailleurs et l'employeur apparaissent diffĂ©rentes (perception du contexte et des normes) et Ă des rĂ©gulations concernant le port de certains Ă©quipements de protection individuel, il s'est agi de comprendre l!activitĂ© et ses diffĂ©rents dĂ©terminants. Recueillir les Ă©lĂ©ments nĂ©cessaires Ă l'adaptation du suivi individuel et Ă la traçabilitĂ© des expositions a permis de co-construire des pistes de solutions avec l'employeur, les salariĂ©s et leurs reprĂ©sentants. Lors de cette intervention les outils ergotoxicologiques et la construction d!objets intermĂ©diaires (Vinck, 2009; Vinck & Laureillard, 1996) Ă©volutifs, ont Ă©tĂ© des leviers pour la construction de pistes de solution. La deuxiĂšme contribution sera prĂ©sentĂ©e par Valentin Lamarque (doctorant en ergonomie) et Guillaume Swierczynski (doctorant en santĂ© publique). Elle portera sur lâhybridation de la SantĂ© publique et de lâergotoxicologie dans un contexte dâexposition des soignants aux cytotoxiques, contenus dans les mĂ©dicaments anti-cancĂ©reux administrĂ©s en service dâoncologie. Lâenjeu de la recherche interventionnelle prĂ©sentĂ©e est la co-construction dâun dispositif de formation en e-learning avec les professionnels concernĂ©s. La troisiĂšme contribution sera prĂ©sentĂ©e par Caroline Esterre (ergonome) et Emilie Bussy (mĂ©trologue) au sein dâun service de santĂ© au travail, lâAHI33. La prĂ©sentation va porter sur lâĂ©tude de l'exposition des soignants aux cytotoxiques (contenus dans les mĂ©dicaments anticancĂ©reux) dans un institut d'oncologie. La question qui va ĂȘtre discutĂ©e est de savoir comment l'activitĂ© de travail des professionnels de santĂ© peut induire des situations d'expositions aux agents cytotoxiques ? Cette question va ĂȘtre traitĂ©e Ă partir : - De lâanalyse de l'activitĂ© de travail des soignants (recherche des situations exposantes) en suivant le produit de sa rĂ©ception Ă son Ă©limination dans l'institut - De prĂ©lĂšvements de surface (identification des sources potentielles dâexposition) - De la restitution des analyses aux salariĂ©s grĂące Ă des objets intermĂ©diaires pour dĂ©velopper les pratiques de prĂ©vention La quatriĂšme contribution sera prĂ©sentĂ©e par Jessie Aldana (toxicologue Ă lâASTI en formation en ergonomie) et MaĂ«l Montigny (en formation en ergonomie). La prĂ©sentation va porter sur lâanalyse de lâactivitĂ© et de lâexposition Ă des produits chimiques dans le cadre de la fabrication d'orthĂšses chez des pĂ©dicures podologues. Cette intervention a permis de mettre en Ă©vidence une exposition au risque chimique potentialisĂ©e par des dĂ©terminants organisationnels et techniques de l'activitĂ©. Des variables ont Ă©tĂ© observĂ©es et ont permis de rĂ©vĂ©ler d'autres facteurs d'expositions aux agents chimiques dangereux. Des observations ouvertes et systĂ©matiques de l'activitĂ© ont Ă©tĂ© couplĂ©s Ă une analyse de danger des produits manipulĂ©s. LâĂ©tude a permis de mettre en corrĂ©lation des signes d'intoxication dĂ©clarĂ©s par les opĂ©rateurs avec les rĂ©sultats de mesures. La cinquiĂšme contribution sera prĂ©sentĂ©e par Caroline Jolly (doctorante en ergonomie, IRSST) et Fabienne Goutille (anthropologue doctorante en ergonomie, Inserm). Elle va porter sur les croisements possible entre analyse de lâactivitĂ©, analyse du contexte de lâactivitĂ© et analyse des expositions aux pesticides du point de vue des agriculteurs. Les deux recherches interventions menĂ©es au Canada et en France viendront illustrer la maniĂšre dont lâergonomie peut contribuer Ă la prĂ©vention du risque pesticides dans deux contextes dâintervention diffĂ©rents (acteurs, rĂ©glementations, technologies, âŠ)
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
Vaccination des jeunes enfants (la réponse d'un laboratoire pharmaceutique à un problÚme de santé publique)
NANCY1-SCD Pharmacie-Odontologie (543952101) / SudocSudocFranceF
Influence of the local environment on lacustrine sedimentary phytolith records
International audienceFossil phytolith assemblages from soils and lake sediments are widely used to reconstruct past vegetationpatterns and dynamics, especially in tropical environments where a phytolith index has been quantitativelycalibrated to estimate tree cover. Most calibration studies have focused on comparing phytolith assemblages inmodern soil with the present aboveground vegetation. However, little is known about phytolith taphonomyand the representativeness of phytolith assemblages and indices in lake sediments. The aim of this study is to im-prove the understanding of the composition of phytolith assemblages and their influx into recent lake sedimentsby comparing them with local land cover assessments. This study focused on three lakes in the Central AfricanRepublic located in savanna, forestâsavanna mosaic, and forest. It appears that the local environment surround-ing the lake was critical for interpreting current and past assemblages, and the ratio of dicotyledon to Poaceaediagnostic phytoliths (the D/P index). The presence of a riparian forest in an open environment had no impacton phytolith assemblages or the D/P index, which instead reflected both the local and regional landscapes. Con-versely, contributions from a marsh, if present in a forested environment, completely dominated the phytolithrecords, which consequently reflected only the local environment of the lake. A high correlation between thePoaceae phytoliths influxes and the charcoal accumulation rates for the two lakes surrounded by a riparian foresthas also been found.Thisfinding,whichwasassociated with a highproportion ofburnedPoaceae phytoliths, pro-vides evidence that Poaceae phytoliths are mainly transported by wind in ash clouds produced byfire
Influence of temperature on surface sediment disturbance by freshwater fish: a microcosm experiment
International audienceWater temperature is a key parameter that regulates activities of ectotherms (e.g., fish) and has been projected to rise in the future in the context of climate change. Surface sediment disturbance (SSD) is an important function performed by fish that modifies benthic habitat properties and may thus influence ecosystem functioning. However, the link between SSD by fish and temperature remains unexplored. In this study, we experimentally assessed the influence of two contrasted temperatures (10 versus 20°C) on SSD by three freshwater fish species in aquaria. After 10 days, the total surface disturbed by the species was approximately 2â3 times higher at warm than at cold temperature but the number and area of patches disturbed by the species were not significantly different. The stone loach Barbatula barbatula, a benthic fish species, had a higher SSD activity (i.e., total surface disturbed, number and size of patches disturbed) both at cold and warm temperatures than two cyprinid species, chub Squalius cephalus and sofie Parachondrostoma toxostoma. On average, SSD by B. barbatula resulted in approximately two and three more patches than the cyprinid species at 10 and 20°C, respectively, and the mean patch area disturbed by B. barbatula was about two times larger than the ones disturbed by the cyprinid species. The total surface disturbed by the cyprinids at warm temperature was roughly equivalent to the surface disturbed by B. barbatula at cold temperature. Our results thus suggest that SSD by fish could increase in future warmed conditions
Hindcasting modelling for restoration and conservation planning: application to stream fish assemblages
International audienceAlthough ecosystems are increasingly threatened worldwide, the resources available to set up management actions, such as conservation or restoration, remain severely limited. Methods designed to spatially allocate conservation and restoration actions while maximizing their ecological benefits are urgently needed. Whereas conservation planning methods have been extensively developed in past decades, improvements in restoration planning are still needed to build efficient management tools. This methodological gap may be explained by the difficulties encountered when estimating non-disturbed ecological conditions (i.e. reference conditions) which are usually required to compare past and present ecosystem states. Here, the species composition of stream fish assemblages in 607 river stretches of the Pas-de-Calais department in the north of France was predicted using species distribution models. Present occurrence was predicted according to four environmental variables, including two related to human-induced disturbances (i.e. proportion of river stretch length affected by hydraulic works and local geomorphological alterations). The fish assemblages potentially present in the absence of such disturbances were then predicted using hindcasting modelling which involves artificially setting to zero the values of the disturbance variables in the models.A framework based on a multi-faceted approach of diversity was applied to the present-day fish assemblages and those predicted under the two non-disturbed scenarios (i.e. restoration scenarios) to assess their suitability for management. While the theoretical restoration of the natural flow regimes was likely to result in few changes in fish assemblage composition and consequently in their multi-faceted diversity, the restoration of natural geomorphological characteristics was predicted to reduce the taxonomic diversity but increase the functional diversity, the natural heritage importance and the socioeconomic value of the fish assemblages.This study provides environmental decision-makers with a tool to identify precisely and simultaneously the conservation and restoration actions that have to be undertaken as a priority, by comparing the present and non-disturbed multi-faceted diversity indices