Exploitation of trophic resources by fish under stressful estuarine conditions

Despite the high complexity and variability of estuaries, these ecosystems are very productive and play an important role in fish feeding. This paper constitutes a preliminary investigation to test how fish optimize the use of the available trophic resources, by studying trophic preference variability and feeding strategies of some pelagic and demersal fish in the Gironde estuary (southwest France). Fish and their prey were collected approximately every two months from July 2003 to June 2004 in the upstream area of the saline estuary. Stomach content analyses were realized to describe the variability of fish feeding according to their size and the time of year. Intra- and interspecific food niche overlap was evaluated using Schoener's index and a cross-calculation method was used to highlight the general fish trends in predation strategy. Stomach content results showed interspecific and intraspecific variability in fish feeding, which can be explained by their different or evolutionary ecomorphology. Their diets are composed mainly of zooplankton and hyperbenthic crustaceans with temporal variations in the consumed taxa. Optimization of the available trophic resource use, a key element in estuarine resilience, is thus possible due to the temporal adaptation of this structural trophic web. However, in spite of their temporal adaptation capacity, most fish species exhibited a specialist feeding strategy. This result was not expected, especially in the high turbidity of the Gironde estuary; the loss of one of these species could affect the fish trophic web structure and hence the resilience of the system

Presence of Palaemon macrodactylus in a Europe estuary: evidence for a successful invasion of the Gironde (SW France)

Palaemon macrodactylus, an exotic shrimp native to the northwest Pacific Ocean, has been recorded in many estuaries along the Atlantic coast of Europe since the late 1990’s. In this study, a regular monthly survey, held since 1992 of the middle section of the Gironde estuary, revealed this species’ rapid and full colonization of the system since its appearance in samples during summer 1998. In the Gironde, the population of P. macrodactylus is self-sustaining and the species is now established there. Our study highlights two important elements that might explain its successful colonization: its ability to quickly invade a niche under-exploited by the similar native species and its greater reproductive output. The species’spatio-temporal distribution in relation to environmental variables was studied and compared with that of the native species P. longirostris. The exotic species was shown to mainly inhabit the polyhaline and mesohaline section of the estuary, which are sections generally under-exploited by females of the native species. Furthermore, fecundity analysis and larval abundance survey results revealed a higher potential fecundity and a greater proportion of larvae and juvenile stages for P. macrodactylus in the natural environment

Risk of Vaccine-Preventable Infections in Swiss Adults with Inflammatory Bowel Disease.

BACKGROUND Patients with inflammatory bowel disease (IBD) have a higher risk of infection and are frequently not up to date with their immunizations. OBJECTIVES This study aims to review vaccination status and evaluate whether age, disease type, or treatment regimen could predict the absence of seroprotection against selected vaccine-preventable infection in adults with IBD. METHODS Cross-sectional study using questionnaire, immunization records review, and assessment of tetanus-specific, varicella-specific, and measles-specific immunoglobulin G concentrations. ClinicalTrials.gov: NCT01908283. RESULTS Among the 306 adults assessed (median age 42.7 years old, 70% with Crohn's disease, 78% receiving immunosuppressive treatment), only 33% had an immunization record available. Absence of seroprotection against tetanus (6%) was associated with increasing age and absence of booster dose; absence of seroprotection against varicella (1%) or measles (3%) was exclusively observed in younger patients with Crohn's disease. There was no statistically significant difference in immunoglobulin concentrations among treatment groups. Although vaccinations are strongly recommended in IBD patients, the frequencies of participants with at least 1 dose of vaccine recorded were low for nearly all antigens: tetanus 94%, diphtheria 87%, pertussis 54%, poliovirus 22%, measles-mumps-rubella 47%, varicella-zoster 0%, Streptococcus pneumoniae 5%, Neisseria meningitidis 12%, hepatitis A 41%, hepatitis B 48%, human papillomavirus 5%, and tick-borne encephalitis 6%. CONCLUSIONS Although many guidelines recommend the vaccination of IBD patients, disease prevention through immunization is still often overlooked, including in Switzerland, increasing their risk of vaccine-preventable diseases. Serological testing should be standardized to monitor patients' protection during follow-up as immunity may wane faster in this population

A Drosophila Pattern Recognition Receptor Contains a Peptidoglycan Docking Groove and Unusual L,D-Carboxypeptidase Activity

The Drosophila peptidoglycan recognition protein SA (PGRP-SA) is critically involved in sensing bacterial infection and activating the Toll signaling pathway, which induces the expression of specific antimicrobial peptide genes. We have determined the crystal structure of PGRP-SA to 2.2-Å resolution and analyzed its peptidoglycan (PG) recognition and signaling activities. We found an extended surface groove in the structure of PGRP-SA, lined with residues that are highly diverse among different PGRPs. Mutational analysis identified it as a PG docking groove required for Toll signaling and showed that residue Ser158 is essential for both PG binding and Toll activation. Contrary to the general belief that PGRP-SA has lost enzyme function and serves primarily for PG sensing, we found that it possesses an intrinsic L,D-carboxypeptidase activity for diaminopimelic acid-type tetrapeptide PG fragments but not lysine-type PG fragments, and that Ser158 and His42 may participate in the hydrolytic activity. As L,D-configured peptide bonds exist only in prokaryotes, this work reveals a rare enzymatic activity in a eukaryotic protein known for sensing bacteria and provides a possible explanation of how PGRP-SA mediates Toll activation specifically in response to lysine-type PG

On the sociohistorical construction of social and economic reserves across the life course and on their use in old age

Coherently with the life course perspective that studies individual life trajectories embedded in sociohistorical changes, this chapter offers a synthesis on the long-term dynamics of vulnerabilities in old age that are associated with a deficit of reserves. In a first time, we investigate how economic, social and health reserves have been unevenly constructed across long lives. The impact of social stratification in the early stage of life, the institutionalization of the life courses and the process of accumulating (dis)advantages are confronted. In a second time, we show how the results of those life course dynamics, the unequal distribution of reserves older adults have to cope with aging, changed during the last 40 years. Undeniable progresses also resulted in new inequalities, or the accentuation of older ones. Third, challenging the classical perspectives of political economy of ageing and social gerontology, we show that depletion is not a linear process but that social inequalities and life accidents play a role. Moreover, coping mechanisms are considered since they tend to be based on reserves’ activation while preserving a level of reserves, for further ageing challenges

The Romantic Socialist Origins of Humanitariamism

“Humanitarian” (humanitaire) came into use in French contemporaneously with the emergence of romantic socialism, and in the context of the rebuilding of post-revolutionary French society and its overseas empire beginning in the 1830s. This article excavates this early idea of humanitarianism, documenting an alternative genealogy for the term and its significance that has been overlooked by scholars of both socialism and humanitarianism. This humanitarianism identified a collective humanity as the source of its own salvation, rather than an external, well-meaning benefactor. Unlike liberal models of advocacy, which invoked individualized actors and recipients of their care, socialists privileged solidarity within their community and rejected the foundational logic of liberal individualism. In tracing this history, this article considers its importance for contemporary debates about humanitarianism’s imperial power dynamics

Nod2 Mediates Susceptibility to Yersinia pseudotuberculosis in Mice

Nucleotide oligomerisation domain 2 (NOD2) is a component of the innate immunity known to be involved in the homeostasis of Peyer patches (PPs) in mice. However, little is known about its role during gut infection in vivo. Yersinia pseudotuberculosis is an enteropathogen causing gastroenteritis, adenolymphitis and septicaemia which is able to invade its host through PPs. We investigated the role of Nod2 during Y. pseudotuberculosis infection. Death was delayed in Nod2 deleted and Crohn's disease associated Nod2 mutated mice orogastrically inoculated with Y. pseudotuberculosis. In PPs, the local immune response was characterized by a higher KC level and a more intense infiltration by neutrophils and macrophages. The apoptotic and bacterial cell counts were decreased. Finally, Nod2 deleted mice had a lower systemic bacterial dissemination and less damage of the haematopoeitic organs. This resistance phenotype was lost in case of intraperitoneal infection. We concluded that Nod2 contributes to the susceptibility to Y. pseudotuberculosis in mice

Mining Big Data for Tourist Hot Spots: Geographical Patterns of Online Footprints

Understanding the complex, and often unequal, spatiality of tourist demand in urban contexts requires other methodologies, among which the information base available online and in social networks has gained prominence. Innovation supported by Information and Communication Technologies in terms of data access and data exchange has emerged as a complementary supporting tool for the more traditional data collection techniques currently in use, particularly, in urban destinations where there is the need to more (near)real-time monitoring. The capacity to collect and analise massive amounts of data on individual and group behaviour is leading to new data-rich research approaches. This chapter addresses the potential for discovering geographical insights regarding tourists’ spatial patterns within a destination, based on the analysis of geotagged data available from two social networks. ·info:eu-repo/semantics/publishedVersio

Surveillance halieutique de l'estuaire de la Gironde : suivi des captures 2010 - étude de la faune circulante 2010

[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [Coll_IRSTEA]Etude Cemagref, groupement de Bordeaux, n°139Ce rapport comprend quatre parties : - une présentation générale du bassin de la Gironde - une étude de la faune circulante aux abords du centre nucléaire de production d'électricité du Blayais - les résultats du suivi des captures 2010 - une synthèse et conclusion générale