158 research outputs found
LATEX10 - LAgrangian Transport EXperiment Data collection Cruise report 2010
Data collection Cruise report 201
Impacts of meso-to submeso-scale features on the ocean circulation in the Coral Sea
International audienceAs part of the South Pacific subtropical gyre, the encounter of the South Equatorial Current (SEC)with the complex bottom topography and numerous islands of the southwest tropical Pacific resultsinto a series of zonal jets, flowing mainly westward off the tip of archipelagos. Moreover, themesoscale activity at basin scale is dominated by westward-propagating nonlinear eddies, with astrong impact on the ocean circulation, the mixing of water masses and tracers' distribution. Eddy-jet interactions are studied here with the data collected in September 2012 during theBIFURCATION cruise in the Coral Sea, under the auspices of SPICE (Southwest PacIfic OceanCirculation and Climate Experiment). We analyze and explain in situ data with the help of satellite-based remote sensing data (altimetry, SSS, SST, ocean color), and we estimate the mass transportbudget within the Coral Sea. We show that the mesoscale activity is a significant contributor to the0-600m transport estimates (5-10 Sv) and is essential for the interpretation of hydrologicalobservations. A specific mesoscale eddy is identified as responsible for the connection between theNorth Vanuatu Jet (NVJ) and the North Caledonian Jet (NCJ). By using a Lagrangian technique, weare able to confirm the long-term connection between the NVJ and the NCJ through mesoscaleactivity. At a smaller scale, our analysis shows that surface temperature and salinity gradients can beassociated with hydrodynamical submesoscale features depicted by Finite Size LyapunovExponents (FSLE). These structures can also be linked to the presence of diazotroph species, incontrast with the general oligotrophy of the area. This study offers interesting outlooks for the useof FSLE to study the distribution of biogeochemical elements
A Connectivity-Based Eco-Regionalization Method of the Mediterranean Sea
International audienceEcoregionalization of the ocean is a necessary step for spatial management of marine resources. Previous ecoregionalization efforts were based either on the distribution of species or on the distribution of physical and biogeochemical properties. These approaches ignore the dispersal of species by oceanic circulation that can connect regions and isolates others. This dispersal effect can be quantified through connectivity that is the probability, or time of transport between distinct regions. Here a new regionalization method based on a connectivity approach is described and applied to the Mediterranean Sea. This method is based on an ensemble of Lagrangian particle numerical simulations using ocean model outputs at 1/12u resolution. The domain is divided into square subregions of 50 km size. Then particle trajectories are used to quantify the oceanographic distance between each subregions, here defined as the mean connection time. Finally the oceanographic distance matrix is used as a basis for a hierarchical clustering. 22 regions are retained and discussed together with a quantification of the stability of boundaries between regions. Identified regions are generally consistent with the general circulation with boundaries located along current jets or surrounding gyres patterns. Regions are discussed in the light of existing ecoregionalizations and available knowledge on plankton distributions. This objective method complements static regionalization approaches based on the environmental niche concept and can be applied to any oceanic region at any scale
Patients\u27 perspectives of tuberculosis treatment challenges and barriers to treatment adherence in Ukraine: a qualitative study
OBJECTIVES: To understand the challenges faced by patients with tuberculosis (TB) and factors that influence TB treatment adherence in Ukraine.
DESIGN: Qualitative study.
SETTING: TB treatment facilities in Kyiv Oblast, Ukraine.
PARTICIPANTS: Sixty adults who had undergone treatment for drug-sensitive TB between June 2012 and August 2015.
METHODS: We conducted semistructured, in-depth, individual interviews among a purposively selected clinical sample of patients previously treated for drug-sensitive TB. Interview content encompassed WHO\u27s framework for barriers to adherence to long-term therapies and included questions about patient preferences and motivators concerning treatment adherence. We examined treatment experience across strata defined by previously identified risk correlates of non-adherence.
RESULTS: Among 60 participants, 19 (32.8%) were HIV positive, 12 (20.3%) had substance use disorder and 9 (15.0%) had not completed TB treatment. Respondents discussed the psychological distress associated with hospital-based TB care, as well as perceived unsupportive, antagonistic interactions with TB providers as major challenges to treatment adherence. An additional barrier to successful treatment completion included the financial toll of lost income during TB treatment, which was exacerbated by the additional costs of ancillary medications and transportation to ambulatory TB clinics. The high pill burden of TB treatment also undermined adherence. These challenges were endorsed among participants with and without major risk factors for non-adherence.
CONCLUSIONS: Our findings highlight important barriers to TB treatment adherence in this study population and suggest specific interventions that may be beneficial in mitigating high rates of poor treatment outcomes for TB in Ukraine
On the influence of coastal mesoscale dynamics on the jellyfish trajectories and distributions
IMAGE DU MOIS AVISO: http://www.aviso.oceanobs.com/en/news/idm/2012/may-2012-jellyfish-on-the-move/print.html ** Résumé de la conférence: http://www.coastalt.eu/files/sandiegoworkshop11/5CA-WS_summary.pdfInternational audienceOceanic mesoscale plays a key role in modulating large-scale circulation, heat fluxes transfer and primary production enhancement. Such hydrodynamic processes are also crucial for jellyfish transport and distribution along the Mediterranean coastal areas. Investigating the relationships between jellyfish distribution and mesoscale hydrodynamic processes therefore provides a rational to understand the influence of such physical structures on the dynamics of regional ecosystems, at the interface between the open ocean and the continental shelf. Nevertheless, the high spatial and temporal variability associated with coastal mesoscale motions makes them difficult to study with sparse in-situ observations. Alternative options rely on developing methodologies based on the combination of multi-sensor platforms in conjunction with numerical simulations. In this respect, we use an advanced Lagrangian particle tracking code developed at LOPB (Marseille, France) to simulate jellyfish trajectories from both a 3D circulation regional model and currents derived from satellite observations. These are obtained by a high resolution altimetric current mapping tools developed at IMEDEA (Majorques, Spain). The large scale signals (~100 km) are removed by subtracting the gridded Sea Level Anomaly maps (AVISO) to improve along track data. In a second step, the residuals are submitted to an objective analysis scheme with correlation scales adjusted to smaller mesoscale and coastal dynamics. Our approach allows us to characterize the main mesoscale features and exchange between the Ligurian Sea and the Gulf of Lion and to infer possible main pathways of jellyfish trajectories
Lagrangian analysis of satellite-derived currents: Application to the North Western Mediterranean coastal dynamics
Revealing important nocturnal and day-to-day variations in fire smoke emissions through a multiplatform inversion
We couple airborne, ground-based, and satellite observations; conduct regional simulations; and develop and apply an inversion technique to constrain hourly smoke emissions from the Rim Fire, the third largest observed in California, USA. Emissions constrainedwithmultiplatform data show notable nocturnal enhancements (sometimes over a factor of 20), correlate better with daily burned area data, and are a factor of 2–4 higher than a priori estimates, highlighting the need for improved characterization of diurnal profiles and day-to-day variability when modeling extreme fires. Constraining only with satellite data results in smaller enhancements mainly due to missing retrievals near the emissions source, suggesting that top-down emission estimates for these events could be underestimated and a multi-platform approach is required to resolve them. Predictions driven by emissions constrained with multi-platform data present significant variations in downwind air quality and in aerosol feedback on meteorology, emphasizing the need for improved emissions estimates during exceptional events
The needs of foster children and how to satisfy them:A systematic review of the literature
Family foster care deeply influences the needs of children and how these are satisfied. To increase our knowledge of foster children’s needs and how these are conceptualized, this paper presents a systematic literature review. Sixty- four empirical articles from six databases were reviewed and categorized (inter-rater agreement K = .78) into four categories: medical, belongingness, psychological and self-actualization needs. The results give a complete overview of needs that are specific to foster children, and what can be implemented to satisfy these needs. This study shows psychological needs are studied more often compared to the other categories, which specially relates to much attention for mental health problems. Furthermore, most articles focus on how to satisfy the needs of foster children and provide no definition or concrete conceptualization of needs. Strikingly, many articles focus on children’s problems instead of their needs, and some even use these terms interchangeably. This review illustrates that future research should employ a proper conceptualization of needs, which could also initiate a shift in thinking about needs instead of problems
The Eurasian Modern Pollen Database (EMPD), version 2
The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019)Swiss National Science Foundation | Ref. 200021_16959
The Eurasian Modern Pollen Database (EMPD), version 2
The Eurasian (nee European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60% from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019).Peer reviewe
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