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Phylogeny and systematics of the Sesamia coniota Hampson species group (Lepidoptera : Noctuidae : Noctuinae : Apameini : Sesamiina), with the description of three new species from the Afrotropical region
In this study, we review six morphologically similar species of Sesamia Guenee, 1852 from Africa, including three new species that are described: Sesamia corymbosus Le Ru n. sp., S. schoenoplectus Le Ru n. sp. and S. temberma Le Ru n. sp. These six species belong to a species complex that we hereby define as the Sesamia coniota group. Host plants of four species are recorded: Schoenoplectus corymbosus (Roth ex Roem. & Schult.) J. Raynal. for S. corymbosus and S. schoenoplectus, Echinochloa pyramidalis (Lam.) Hitschc. & Chase, Eriochloa meyeriana (Nees) Pilg., Schoenoplectus corymbosus and Typha latifolia L. for S. jansei, Tams & Bowden, 1953 and Pennisetum sp. for S. temberma. We also conduct molecular phylogenetic analyses on a multimarker (four mitochondrial and two nuclear genes) molecular dataset encompassing 36 specimens (including 32 specimens belonging to the S. coniota group). Molecular analyses allow assessing the phylogenetic relationships of five out of six species of the group
The three dialectics of adaptation finance in Vietnam
The goal of this paper is to analyze the complex institutional landscape of adaptation finance in Vietnam, a middle-income country highly vulnerable to the impact of climate change. While resources from international organizations and national authorities occupy a prominent position in adaptation funding, the use of local resources that directly or indirectly support adaptation practices is also an important factor to consider. We hypothesize that it is that interplay between official climate change finance on the one hand and local social dynamics on the other hand that shapes the structure of adaptation funding. These very particular financing circuits consequently determine the kind of adaptation actions that are actually implemented. The paper unfolds the adaptation finance flows at all scales by using qualitative field studies, technical and legal reports, and a wide-ranging literature on adaptation project financing, and thus identifies three types of dialectical tensions that might hinder Vietnamese institutional readiness for adaptation finance: the adaptation/development financing nexus, the adaptation/reaction financing behaviors, and the endogenous/exogenous financing dichotomy. Ultimately, the paper derives from these dialectical tensions within the architecture and functioning of adaptation finance key takeaway messages for a prospective analysis of adaptation funding that better informs adaptation finance policies
Current needs for climate services in West Africa : results from two stakeholder surveys
Climate services have been criticised in the past for their tendency to only disseminate results from climate research, rather than to seek to understand and tailor to the needs of their target audiences. Two surveys have been conducted within two projects, ISIpedia and CLIMAP, to assess users' needs for climate and climate impacts information of all countries (with a foremost focus on West Africa) and for Senegal. The joint analysis of the results showed that climate and climate-impact information is very relevant for West African respondents' activities but a number of barriers prevent existing climate services from fully fulfilling the role they could play in this respect. Consistently across both surveys, the respondents highlighted the irrelevance or the incompleteness of the information that current climate services provide, which is mostly related to the lack of high-resolution information or high uncertainties, as the biggest barriers. Both surveys showed that the lack of training to understand the provided information is also an important barrier, which calls for the organisation of capacity-building activities to ensure the uptake of the information by their target audiences. Overall, the survey responses demonstrated the importance of stakeholder engagement to ensure the usefulness of climate services in West Africa. In addition, appropriate integration of the existing climate services within the national contexts as well as their dissemination within the ecosystem of information portals and products appear to be essential to ensure their effectiveness
Culturing ancient bacteria carrying resistance genes from permafrost and comparative genomics with modern isolates
Long considered to be a consequence of human antibiotics use by deduction, antibiotic resistance mechanisms appear to be in fact a much older phenomenon as antibiotic resistance genes have previously been detected from millions of year-old permafrost samples. As these specimens guarantee the viability of archaic bacteria, we herein propose to apply the culturomics approach to recover the bacterial content of a Siberian permafrost sample dated, using the in situ-produced cosmogenic nuclide chlorine36 (Cl-36), at 2.7 million years to study the dynamics of bacterial evolution in an evolutionary perspective. As a result, we cultured and sequenced the genomes of 28 ancient bacterial species including one new species. To perform genome comparison between permafrost strains and modern isolates we selected 7 of these species (i.e., Achromobacter insolitus, Bacillus idriensis, Brevundimonas aurantiaca, Janibacter melonis, Kocuria rhizophila, Microbacterium hydrocarbonoxydans and Paracoccus yeei). We observed a high level of variability in genomic content with a percentage of shared genes in the core genomes ranging from 21.23% to 55.59%. In addition, the Single Nucleotide Polymorphism (SNP) comparison between permafrost and modern strains for the same species did not allow a dating of ancient strains based on genomic content. There were no significant differences in antibiotic resistance profiles between modern and ancient isolates of each species. Acquired resistance to antibiotics was phenotypically detected in all gram-negative bacterial species recovered from permafrost, with a significant number of genes coding for antibiotic resistance detected. Taken together, these findings confirm previously obtained data that antibiotic resistance predates humanity as most of antimicrobial agents are natural weapons used in inter-microbial conflicts within the biosphere
A Dynamic Energy Budget simulation approach to investigate the eco-physiological factors behind the two-stanza growth of yellowfin tuna (Thunnus albacares)
The growth of yellowfin tuna has been the subject of considerable research efforts since the early 1960s. Most studies support a complex two-stanza growth pattern with a sharp acceleration departing from the von Bertalanffy growth curve used for most fish populations. This growth pattern has been assumed to result from a combination of physiological, ecological and behavioral factors but the role and contribution of each of them have not been addressed yet. We developed a bioenergetic model for yellowfin tuna in the context of Dynamic Energy Budget theory to mechanistically represent the processes governing yellowfin tuna growth. Most parameters of the model were inferred from Pacific bluefin tuna using body-size scaling relationships while some essential parameters were estimated from biological data sets collected in the Indian Ocean. The model proved particularly suitable for reproducing the data collected during the Pacific yellowfin tuna farming experience conducted by the Inter-American Tropical Tuna Commission at the Achotines Laboratory in Panama. In addition, model predictions appeared in agreement with knowledge of the biology and ecology of wild yellowfin tuna. We used our model to explore through simulations two major assumptions that might explain the existence of growth stanzas observed in wild yellowfin tuna: (i) a lower food supply during juvenile stage in relation with high infra- and inter-species competition and (ii) ontogenetic changes in food diet. Our results show that both assumptions are plausible although none of them is self-sufficient to explain the intensity of growth acceleration observed in wild Indian Ocean yellowfin tuna, suggesting that the two factors may act in concert. Our study shows that the yellowfin growth pattern is likely due to behavioral changes triggered by the acquisition of physiological abilities and anatomical traits through ontogeny that result in a major change in intensity of schooling and in a shift in the biotic habitat and trophic ecology of this commercially important tuna species
Coastal sea level rise at Senetosa (Corsica) during the Jason altimetry missions
In the context of the ESA Climate Change Initiative project, we are engaged in a regional reprocessing of high-resolution (20 Hz) altimetry data of the classical missions in a number of the world's coastal zones. It is done using the ALES (Adaptive Leading Edge Subwave-form) retracker combined with the X-TRACK system dedicated to improve geophysical corrections at the coast. Using the Jason-1 and Jason-2 satellite data, high-resolution, along-track sea level time series have been generated, and coastal sea level trends have been computed over a 14-year time span (from July 2002 to June 2016). In this paper, we focus on a particular coastal site where the Jason track crosses land, Senetosa, located south of Corsica in the Mediterranean Sea, for two reasons: (1) the rate of sea level rise estimated in this project increases significantly in the last 4-5 km to the coast compared to what is observed further offshore, and (2) Senetosa is the calibration site for the TOPEX/Poseidon and Jason altimetry missions, which are equipped for that purpose with in situ instrumentation, in particular tide gauges and a Global Navigation Satellite System (GNSS) antenna. A careful examination of all the potential errors that could explain the increased rate of sea level rise close to the coast (e.g., spurious trends in the geophysical corrections, imperfect inter-mission bias estimate, decrease of valid data close to the coast and errors in waveform retracking) has been carried out, but none of these effects appear able to explain the trend increase. We further explored the possibility that it results from real physical processes. Change in wave conditions was investigated, but wave setup was excluded as a potential contributor because the magnitude was too low and too localized in the immediate vicinity of the shoreline. A preliminary model-based investigation about the contribution of coastal currents indicates that it could be a plausible explanation of the observed change in sea level trend close to the coast
A spatial food web model to investigate potential spillover effects of a fishery closure in an offshore wind farm
There is a growing interest in the development of offshore wind farms to provide a sustainable source of renewable energy and contribute to the reduction of carbon emissions. In parallel, there is a need to better understand the effects of these installations on coastal marine ecosystems and identify potential sea use conflicts, especially when the area is subject to access restrictions. This study investigated the effects of a spatial closure during the exploitation phase of an offshore wind farm in the extended Bay of Seine (English Channel, France) using Ecospace, a spatially and temporally explicit module of Ecopath with Ecosim. To address this question, simulations were conducted through the evaluation of "what-if scenarios" to assess the effectiveness of a fishing exclusion zone inside and surrounding the offshore wind farm. Several biomass, catch and trophic level-based indicators were calculated to evaluate how the exclusion zone could affect fishing activities and main components of the food web. All the indicators were estimated in the extended Bay of Seine and summarized by subarea. Findings suggested that the spillover effect could mitigate the negative impact of access loss on fishing activities, in a scenario of simulated closure of the area of the wind farm. The Ecospace model predicted an increase of catches (up to 7% near the wind farm) and a slight increase in the proportion of high trophic level species. However, the influence of spillover effects is limited in space and the expected increase of biomass and catches are highly localized in areas around the offshore wind farm installations. At the scale of the Bay of Seine, further analysis of the spillover effects revealed a spatial pattern and suggested that the implementation of an exclusion zone inside the offshore wind farm could concentrate highly mobile predators
Prevalence and factors associated with hepatitis B and D virus infections among migrant sex workers in Chiangmai, Thailand : a cross-sectional study in 2019
Objectives: To determine the prevalence of hepatitis B surface antigen (HBsAg) and antibody to hepatitis delta virus (anti-HDV) and associated factors among migrant sex workers in Chiangmai, Thailand. Methods: This cross-sectional study was conducted at various sexual entertainment venues in Chiangmai, Thailand, in 2019. Consenting participants were interviewed using a questionnaire, and plasma was tested for hepatitis B virus (HBV) markers (DiaSorin, Italy) and anti-HDV antibody (DIA.PRO Diagnostic Bioprobes, Italy), if HBsAg-positive. Associations between HBsAg positivity or HDV antibody and potential factors were examined using univariable and multivariable logistic regression analysis. Results: A total of 396 migrant sex workers, half of them female, were recruited between February and September 2019. Their median age was 25 years (interquartile range 22-30 years) and 95% were Burmese. Overall, HBsAg prevalence was 11.4%; 8.1% in females and 14.7% in males (Chi-square, p = 0.040). One-third were still susceptible to HBV. No HBsAg-positive participants had anti-HDV antibodies. HBsAg positivity was associated with being male (adjusted odds ratio (aOR) 3.01, 95% confidence interval (CI) 1.25-7.68, p = 0.014), having attended school (aOR 4.50, 95% CI 1.26-15.98, p = 0.020), being separated/divorced/widowed (aOR 5.77, 95% CI 1.48-22.52, p = 0.012), and having unprotected sex (aOR 3.38, 95% CI 1.31-8.71, p = 0.012). Conclusions: In this young population, higher HBsAg prevalence in males may be related to sexual transmission, indicating the need for HBV screening programs linked with HBV prevention and care
Description of Gracilibacillus phocaeensis sp. nov., a new halophilic bacterium isolated from Senegalian human stool
Using the taxonogenomics method, we describe Gracilibacillus phocaeensis strain Marseille-P3801, a new species previously isolated from a salty stool of a 20-year-old man from N'Diop, Senegal. It is a Gram-positive, aerobic and motile bacillus. The major fatty acids are C-15:0anteiso (59%), C-16:0 (16%) and C17:0-anteiso (11%). Strain Marseille-P3801 exhibits a 98.45% sequence similarity with Gracilibacillus thailandensis strain TP2-8, the phylogenetically closest species. Its genome is 4.66 Mb with 39.6 mol% G + C content
Impact of counseling methods on HIV retesting uptake in at-risk individuals : a randomized controlled study
Systematic face-to-face pre-HIV test counseling is costly and may discourage clients to present for regular testing. In a randomized, controlled, non-inferiority trial conducted in four facilities providing free-of-charge anonymous HIV testing in Thailand, participants received either: standard counseling according to national guidelines (reference); computer-assisted counseling: interactive counseling on a tablet computer followed by an invitation to ask questions to the counselor; or on-demand counseling: invitation to ask questions to the counselor. Primary endpoint was a HIV retest within 7 months after enrolment visit. Following the planned interim analysis, on-demand counseling was discontinued for futility. In the final analysis in 1036 HIV-uninfected at-risk participants, computer-assisted counseling was non-inferior to standard counseling and had similar acceptability and improvements in HIV knowledge and sexual risk behaviors; however, it significantly reduced the time spent by counselors on counseling. Implementation of pre-HIV test computer-assisted counseling may ease the burden on staff involved in HIV testing