7 research outputs found

    Morphometric and allozyme variation in the African catfishes <i>Clarias gariepinus</i> and <i>C. anguillaris</i>

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    This study investigated morphological characters and electrophoretic polymorphism at 25 protein loci in nine wild populations of the African clariid catfish Clarias gariepinus and seven wild populations of C. anguillaris. Two other clariid species, Clarias albopunctatus and Heterobranchus longifilis, were used as outgroups in the allozyme study. Morphometric and allozyme data are congruent for the Nilo-Sudanian populations of C. gariepinus and C. anguillaris. Both approaches also distinguished two groups amongst the C. gariepinus populations, one containing Nilo-Sudanian populations and the other including Lake Victoria and southern African populations. However, allozyme data suggest that C. gariepinus is not a monophyletic group and show that C. albopunctatus is more divergent from C. gariepinus and C. anguillaris than it is from H. longifilis, stressing the need for a revision of clariid systematics. The variation observed in C. gariepinus is discussed in terms of palaeogeographical events and its use in aquaculture

    Morphometric and allozyme variation in the african catfishes Clarias gariepinus and C. anguillaris

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    This study investigated morphological characters and electrophoretic polymorphism at 25 protein loci in nine wild populations of the African clariid catfish #Clarias gariepinus and seven wild populations of #C. anguillaris. Two other clariid species, #Clarias albopunctatus and #Heterobranchus longifilis, were used as outgroups in the allozyme study. Morphometric and allozyme data are congruent for the Nilo-Sudanian populations of #C. gariepinus and #C. anguillaris. Both approaches also distinguished two groups amongst the #C. gariepinus populations, one containing Nilo-Sudanian populations and the other including Lake Victoria and southern African populations. However, allozyme data suggest that #C. gariepinus is not a monophyletic group and show that #C. albopunctatus is more divergent from #C. gariepinus and #C. anguillaris than it is from #H. longifilis, stressing the need for a revision of clariid systematics. The variation observed in #C. gariepinus$ is discussed in terms of palaeogeographical events and its use in aquaculture. (Résumé d'auteur

    Morphometric and allozyme variation in the african catfishes Clarias gariepinus and C. anguillaris

    No full text
    This study investigated morphological characters and electrophoretic polymorphism at 25 protein loci in nine wild populations of the African clariid catfish #Clarias gariepinus and seven wild populations of #C. anguillaris. Two other clariid species, #Clarias albopunctatus and #Heterobranchus longifilis, were used as outgroups in the allozyme study. Morphometric and allozyme data are congruent for the Nilo-Sudanian populations of #C. gariepinus and #C. anguillaris. Both approaches also distinguished two groups amongst the #C. gariepinus populations, one containing Nilo-Sudanian populations and the other including Lake Victoria and southern African populations. However, allozyme data suggest that #C. gariepinus is not a monophyletic group and show that #C. albopunctatus is more divergent from #C. gariepinus and #C. anguillaris than it is from #H. longifilis, stressing the need for a revision of clariid systematics. The variation observed in #C. gariepinus$ is discussed in terms of palaeogeographical events and its use in aquaculture. (Résumé d'auteur

    Harmonized in situ datasets for agricultural land use mapping and monitoring in tropical countries.

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    The availability of crop type reference datasets for satellite image classification is very limited for complex agricultural systems as observed in developing and emerging countries. Indeed, agricultural land use is very dynamic, agricultural censuses are often poorly georeferenced and crop types are difficult to interpret directly from satellite imagery. In this paper, we present a database made of 24 datasets collected in a standardized manner over nine sites within the framework of the international JECAM (Joint Experiment for Crop Assessment and Monitoring) initiative; the sites were spread over seven countries of the tropical belt, and the number of data collection years depended on the site (from 1 to 7 years between 2013 and 2020). These quality-controlled datasets are distinguished by in situ data collected at the field scale by local experts, with precise geographic coordinates, and following a common protocol. Altogether, the datasets completed 27 074 polygons (20 257 crops and 6817 noncrops, ranging from 748 plots in 2013 (one site visited) to 5515 in 2015 (six sites visited)) documented by detailed keywords. These datasets can be used to produce and validate agricultural land use maps in the tropics. They can also be used to assess the performances and robustness of classification methods of cropland and crop types/practices in a large range of tropical farming systems. The dataset is available at https://doi.org/10.18167/DVN1/P7OLAP (Jolivot et al., 2021)

    Allozyme variation in natural and cultured populations in two tilapia species: Oreochromis niloticus and Tilapia zillii

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    We investigated the electrophoretic polymorphism at 30 protein loci in 27 wild and cultured populations of two tilapia species, Tilapia zillii and Oreochromis niloticus. Single and joint segregations were analysed at 12 polymorphic loci in full-sib families. All the loci showed single segregation in agreement with the Mendelian expectations, and two nonrandom joint segregations were found. In total, 26 loci were polymorphic and 12 were diagnostic between the two species. A pronounced differentiation was observed between the Ivory Coast and Nilo-Sudanian T. zillii populations (average Nei's standard genetic distance = 0.13). Within the Nilo-Sudanian region, the level of variation observed in O. niloticus and T. zillii was rather low when compared with other freshwater species analysed at similar macrogeographical scales. The same pattern of geographical differentiation was found between the west and east African populations in both species suggesting that this structuring mainly reflected the same palaeo-geographical events. Most of the geographical variation observed in the Nile tilapia populations analysed here was present in the cultured stocks. In contrast to fish-farmed stocks analysed in other countries, those from the Ivory Coast and Niger displayed neither evidence of loss of genetic diversity nor any trace of introgression with other cultured tilapia species, indicating that these stocks have been properly managed

    Clinical picture and treatment of 2212 patients with common variable immunodeficiency.

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    BACKGROUND: Common variable immunodeficiency (CVID) is an antibody deficiency with an equal sex distribution and a high variability in clinical presentation. The main features include respiratory tract infections and their associated complications, enteropathy, autoimmunity, and lymphoproliferative disorders. OBJECTIVE: This study analyzes the clinical presentation, association between clinical features, and differences and effects of immunoglobulin treatment in Europe. METHODS: Data on 2212 patients with CVID from 28 medical centers contributing to the European Society for Immunodeficiencies Database were analyzed retrospectively. RESULTS: Early disease onset (<10 years) was very frequent in our cohort (33.7%), especially in male subjects (39.8%). Male subjects with early-onset CVID were more prone to pneumonia and less prone to other complications suggesting a distinct disease entity. The diagnostic delay of CVID ranges between 4 and 5 years in many countries and is particularly high in subjects with early-onset CVID. Enteropathy, autoimmunity, granulomas, and splenomegaly formed a set of interrelated features, whereas bronchiectasis was not associated with any other clinical feature. Patient survival in this cohort was associated with age at onset and age at diagnosis only. There were different treatment strategies in Europe, with considerable differences in immunoglobulin dosing, ranging from 130 up to 750 mg/kg/mo. Patients with very low trough levels of less than 4 g/L had poor clinical outcomes, whereas higher trough levels were associated with a reduced frequency of serious bacterial infections. CONCLUSION: Patients with CVID are being managed differently throughout Europe, affecting various outcome measures. Clinically, CVID is a truly variable antibody deficiency syndrome
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