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Impact of nutrient availability on the trophic strategies of the planktonic protist communities in a disturbed Mediterranean coastal lagoon
No full textThe impact of changes in nitrogen (N) and phosphorus (P) availability on the trophic strategies of planktonic protists was evaluated in a disturbed Mediterranean lagoon (Biguglia lagoon, France) using short-term bioassays. Natural communities were collected in three periods, i.e., autumn, spring and summer, to address the influence of the different environmental conditions. The responses of autotrophic plankton communities to experimentally induced N and/or P limitations were assessed as changes in chlorophyll a (Chl a) concentrations and in the abundances of potentially mixotrophic protists taxa. We observed blooms (> 10(5) cells l(-1)) of nanoflagellates in autumn, and of phycocyanin-rich picocyanobacteria in summer. Communities showed a co-limitation by N and P at the three sampling periods, despite high N:P ratios in autumn and spring. The high abundances of potentially mixotrophic dinoflagellates during these periods suggest the involvement of alternative trophic pathways for their maintenance in the lagoon. After bioassay incubations using different nutrient enrichment treatments, we often observed reduced abundances of mixotrophic protists containing Chl a with a concomitant increased abundance of protists without Chl a. This indicates a loss of chloroplasts and photoautotrophic abilities in protists cells, possibly reflecting a shift towards heterotrophy that could be sustained by phagotrophy
A new species of Schismatogobius (Teleostei: Gobiidae) from Sulawesi (Indonesia)
No full textA new species of Schismatogobius, a freshwater goby, is described from Sulawesi (Indonesia). It differs from other species belonging to the genus by a high percentage of genetic divergence in partial COI gene (652 bp) and by several characters, including the number of pectoral fin rays, the pectoral fin colour pattern, the jaw length/head length ratio and the preanal length
Lieux de mémoire sonore : des sons pour survivre, des sons pour tuer
No full textQuels sens donner aux pratiques sonores et musicales dans les situations de violence organisée ? Comment penser la relation dynamique qu'entretient le son avec l'expérience sensible des lieux, des personnes et des événements ? Ce livre est organisé autour de deux propositions. La première est que les expériences sonores en contexte de violence organisée peuvent être comprises non seulement comme des événements politiques, mais comme ce que nous proposons d'appeler des "lieux de mémoire sonore". Notre seconde proposition est que ces lieux de mémoire sonore peuvent être appréhendés sous une double perspective, à la fois la face noire et la face lumineuse d'un même phénomène. D'une part, le son, la musique et le silence sont utilisés comme des armes en contexte de violence organisée, que cela soit par exemple dans certains lieux de détention ou en situation de guerre ou de conflit politique. D'autre part, ils constituent des ressources symboliques qui contribuent à la (re)construction de subjectivités, notamment dans des situations faisant suite à des expériences d'exil forcé et de violence organisée. Lieux de mémoire sonore est une somme exceptionnelle sur les usages des sons et des pratiques musicales dans des situations de crise humanitaire, de guerre civile, d'exil ou de catastrophe naturelle. Ce travail conjoint entre chercheurs et musiciens présente différents contextes de violence organisée, et les exemples choisis couvrent de nombreuses régions du globe, depuis le Liban, la Syrie ou le Vanuatu jusqu'au Canada, au Viêt Nam et plusieurs pays européens
Is patient navigation a solution to the problem of "leaving no one behind" ? : a scoping review of evidence from low-income countries
No full textPatient navigation interventions, which are designed to enable patients excluded from health systems to overcome the barriers they face in accessing care, have multiplied in high-income countries since the 1990s. However, in low-income countries (LICs), indigents are generally excluded from health policies despite the international paradigm of universal health coverage (UHC). Fee exemption interventions have demonstrated their limits and it is now necessary to act on other dimensions of access to healthcare. However, there is a lack of knowledge about the interventions implemented in LICs to support the indigents throughout their care pathway. The aim of this paper is to synthesize what is known about patient navigation interventions to facilitate access to modern health systems for vulnerable populations in LICs. We therefore conducted a scoping review to identify all patient navigation interventions in LICs. We found 60 articles employing a total of 48 interventions. Most of these interventions targeted traditional beneficiaries such as people living with HIV, pregnant women and children. We utilized the framework developed by Levesque et al. (Patient-centred access to health care: conceptualising access at the interface of health systems and populations. Int J Equity Health 2013;12:18) to analyse the interventions. All acted on the ability to perceive, 34 interventions on the ability to reach, 30 on the ability to engage, 8 on the ability to pay and 6 on the ability to seek. Evaluations of these interventions were encouraging, as they often appeared to lead to improved health indicators and service utilization rates and reduced attrition in care. However, no intervention specifically targeted indigents and very few evaluations differentiated the impact of the intervention on the poorest populations. It is therefore necessary to test navigation interventions to enable those who are worst off to overcome the barriers they face. It is a major ethical issue that health policies leave no one behind and that UHC does not benefit everyone except the poores
Impact of city historical management on soil organic carbon stocks in Paris (France)
No full textPurpose Assessments of urban soil organic carbon stock (SOCS) are scant because citywide data are scarce. Moreover, we do not know which factors mostly explain SOCS spatial and temporal variations in urban open soils. Methods To fill these knowledge gaps, the present study focused on Paris (France): two periods (1993-2007 and 2008-2016) were compared to better understand SOCS changes at 0-30 cm depth. The effects of anthropic factors (land use, management intensity, cover type, site age and size, city district, and indirectly, resource material used for the site establishment) and soil properties (e.g., soil nutrient contents) on SOCS were studied over the more recent period (2008-2016) on 810 soil samples. Results The changes in green space management methods between both periods resulted in an additional storage of + 43.5 Gg SOC in Paris open soils in 2008-2016 compared to 1993-2007. During 2008-2016, SOCS was still influenced by city history and particularly by the type of resource material used for landscaping, which has changed since the 1950s. SOCS differed significantly among city districts, which represent a combination of all studied anthropic factors: each district has its own history (i.e., soil resource material, green space age), specific number and size of green spaces, current management methods, and plant cover types. Paris green space SOCS was also influenced by soil nitrogen, sand, and magnesium contents as well as pH. Conclusions Modifications of local landscape management methods are a main driver of SOCS changes. Moreover, citywide SOCS distribution tends to depend on city history
Benefits of radar-derived surface current assimilation for South of Africa ocean circulation
No full textThe oceanic circulation south of Africa is characterised by a complex dynamics with a strong variability due to the presence of the Agulhas current and numerous eddies. This area of interest is also the location of several natural gas fields under seafloor which are targeted for drilling and exploitation. The complex and powerful ocean currents induces significant issues for ship operations at the surface as well as under the surface for deep sea operations. Therefore, the knowledge of the state of the currents and the ability to forecast them in a realistic manners could greatly enforce the safety of various marine operation. Following this objective, an array of HF radar systems were deployed to allow a detailed knowledge of the Agulhas currents and its associated eddy activity. It is shown in this study that assimilation of HF radar allow to represent the surface circulation more realistically. Two kind of experiments have been performed, a one month analysis and nine consecutive forecast of two days each. The one month 4DVAR experiment have been compared to geostrophic currents issued from altimeters and highlight an important improvement of the geostrophic currents. Furthermore despite the restricted size of the area covered with HF radar, we show that the solution is improved almost in the whole domain, mainly upstream and downstream of the HF radar's covered area. We also show that while benefits of the assimilation on the surface current intensity is significantly reduced during the second day of forecast, the correction in direction persists after 48 h
Effects of nickel oxide nanoparticles on survival, reproduction, and oxidative stress biomarkers in the marine calanoid copepod Centropages ponticus under short-term exposure
No full textExcessive use of nickel oxide nanoparticles (NiO NPs) in various industrial and commercial products can lead to various negative effects in human and environmental health due to their possible discharge into the environment. Nerveless, information about their ecotoxicological effects on marine organisms are lacking. Copepods are good ecotoxicological models because of their high sensitivity to environmental stress and their key role in the marine food webs. In this study, 48 h acute tests were conducted on the marine planktonic copepod Centropages ponticus to assess lethal and sublethal toxicities of NiO NPs. The results revealed LC50 (48 h) of 4 mg/L for adult females. Aggregation and settling of NiO NPs were observed at concentrations >= 2 mg/L. Exposure to sublethal concentrations (>= 0.02 mg/L for 48 h) had significant negative effects on reproductive success in C. ponticus. Egg production after 24 h and 48 h decreased by 32% and 46%, respectively at 0.02 mg/L and 70% and 82%, respectively, at 2 mg/L. Hatching success was reduced by 70% and 79% at 2 mg/L for eggs produced after 24 h and 48 h respectively. Antioxidant enzymatic activity increased significantly with NiO NP concentration and time, indicating that NiO NPs can cause oxidative stress in C. ponticus even under short-term exposure, while significant inhibition of acetylcholinesterase activity at 2 mg/L after 48 h suggests neurotoxic effects of NiO NPs
Seasonally stable temperature gradients through supraglacial debris in the Everest region of Nepal, Central Himalaya
No full textRock debris covers similar to 30% of glacier ablation areas in the Central Himalaya and modifies the impact of atmospheric conditions on mass balance. The thermal properties of supraglacial debris are diurnally variable but remain poorly constrained for monsoon-influenced glaciers over the timescale of the ablation season. We measured vertical debris profile temperatures at 12 sites on four glaciers in the Everest region with debris thickness ranging from 0.08 to 2.8 m. Typically, the length of the ice ablation season beneath supraglacial debris was 160 days (15 May to 22 October)-a month longer than the monsoon season. Debris temperature gradients were approximately linear (r(2) > 0.83), measured as -40 degrees C m(-1) where debris was up to 0.1 m thick, -20 degrees C m(-1) for debris 0.1-0.5 m thick, and -4 degrees C m(-1) for debris greater than 0.5 m thick. Our results demonstrate that the influence of supraglacial debris on the temperature of the underlying ice surface, and therefore melt, is stable at a seasonal timescale and can be estimated from near-surface temperature. These results have the potential to greatly improve the representation of ablation in calculations of debris-covered glacier mass balance and projections of their response to climate change
