scholarly journals Cryptic diversity and gene introgression of Moinidae (Crustacea: Cladocera) in Nigeria

2021 ◽  
Vol 90 (4-5) ◽  
pp. 463-486
Author(s):  
Zhixiong Deng ◽  
Yijun Ni ◽  
Jinhui Wang ◽  
Chike Chukwuenyem Ebido ◽  
Elijah Chibueze Odii ◽  
...  

Abstract The distribution and species/lineage diversity of freshwater invertebrate zooplankton is understudied in Sub-Saharan Africa. In the present study, we explored the lineage diversity and regional distribution of Moinidae (Crustacea: Cladocera) species in Southeast Nigeria. Three species of Moinidae were identified, based on morphology, in 11 of 32 Nigerian lakes examined. Their phylogenetic relationships were investigated based on mitochondrial dna sequences (cytochrome oxidase c subunit I gene; coi) and two nuclear internal transcribed spacer regions (its-1 and its-2). Three coi lineages were detected, corresponding to the morphological species. Two of the coi lineages are newly reported, but one coi lineage (and the haplotype found) is globally distributed, suggesting an ability of moinids to disperse over long distances. Interestingly, two individuals that were morphologically M. cf. macrocopa and had its alleles typical of that species had mtDNA sequences typical of M. cf. micrura. Additionally, one individual that corresponded morphologically to M. cf. macrocopa (and also had a mitochondrial sequence typical of M. cf. micrura) had one its-2 allele typical of that species and one typical of M. cf. micrura. This discordance between mtDNA and nuclear phylogenies suggests gene introgression and/or hybridization between different species within the genus. Our data shows the lineage distribution/diversity and the presence of gene introgression/interspecific hybridization among moinid species from a tropical region.

2020 ◽  
Author(s):  
Fabio Clementi ◽  
Michele Fabiani ◽  
Vasco Molini

Abstract The resurgence of economic growth over the last two decades in sub-Saharan Africa has recently come under scrutiny by scholars, the main criticism being the lack of inclusiveness. While studies on inequality in sub-Saharan Africa are becoming numerous, less attention has been devoted so far to the growing polarization the region is undergoing. Polarization, as distinct from inequality, refers to the tendency of shifting away from the centre of a distribution to its tails, creating a hollowed-out middle. This paper, using a set of sub-Saharan African national household surveys, provides a first estimate of the regional expenditures’ polarization. This latter steadily increased throughout the 2000s and its growth was mainly driven by increasing polarization between countries, meaning sub-Saharan Africa tended to polarize spatially, with the Southern cone countries and some Western African countries performing above the average, and the rest of the region lagging behind.


2021 ◽  
Vol 3 (2) ◽  
pp. 286-296
Author(s):  
Vanona Noelson Jean Christophe ◽  
◽  
Raminosoa Chrysostome ◽  
Modeste Kameni Nematchoua ◽  
◽  
...  

Energy demand varies depending on the location chosen for construction. The main objective of this research is to analyze the bioclimatic potential of different climatic zones in different regions of Madagascar. For this, this research assesses and compares the indoor air temperature, the energy requirement, the carbon emission and the relative humidity in a traditional building commonly found in cities in sub-Saharan Africa, which was designed to be placed in four cities unevenly distributed in four climatic zones of Madagascar. In order to achieve this goal, hourly meteorological data for the past thirty years has been analyzed for two seasons (dry season and rainy season). At the same time, the adaptive comfort model defined by ASHRAE 55 served as a reference for evaluating the different potentials of passive design. The results showed that by 2030 the need for energy is expected to increase globally in these different cities studied. Like other countries around the world, it is recommended that countries in Sub-Saharan Africa conduct more of this kind of energy. Study in order to establish a construction standard specific to this region of the world.


2017 ◽  
Vol 1 (6) ◽  
pp. 533-537
Author(s):  
Lorenz von Seidlein ◽  
Borimas Hanboonkunupakarn ◽  
Podjanee Jittmala ◽  
Sasithon Pukrittayakamee

RTS,S/AS01 is the most advanced vaccine to prevent malaria. It is safe and moderately effective. A large pivotal phase III trial in over 15 000 young children in sub-Saharan Africa completed in 2014 showed that the vaccine could protect around one-third of children (aged 5–17 months) and one-fourth of infants (aged 6–12 weeks) from uncomplicated falciparum malaria. The European Medicines Agency approved licensing and programmatic roll-out of the RTSS vaccine in malaria endemic countries in sub-Saharan Africa. WHO is planning further studies in a large Malaria Vaccine Implementation Programme, in more than 400 000 young African children. With the changing malaria epidemiology in Africa resulting in older children at risk, alternative modes of employment are under evaluation, for example the use of RTS,S/AS01 in older children as part of seasonal malaria prophylaxis. Another strategy is combining mass drug administrations with mass vaccine campaigns for all age groups in regional malaria elimination campaigns. A phase II trial is ongoing to evaluate the safety and immunogenicity of the RTSS in combination with antimalarial drugs in Thailand. Such novel approaches aim to extract the maximum benefit from the well-documented, short-lasting protective efficacy of RTS,S/AS01.


1993 ◽  
Vol 47 (3) ◽  
pp. 555-556
Author(s):  
Lado Ruzicka

Crisis ◽  
2011 ◽  
Vol 32 (1) ◽  
pp. 43-51 ◽  
Author(s):  
Eugene Kinyanda ◽  
Ruth Kizza ◽  
Jonathan Levin ◽  
Sheila Ndyanabangi ◽  
Catherine Abbo

Background: Suicidal behavior in adolescence is a public health concern and has serious consequences for adolescents and their families. There is, however, a paucity of data on this subject from sub-Saharan Africa, hence the need for this study. Aims: A cross-sectional multistage survey to investigate adolescent suicidality among other things was undertaken in rural northeastern Uganda. Methods: A structured protocol administered by trained psychiatric nurses collected information on sociodemographics, mental disorders (DSM-IV criteria), and psychological and psychosocial risk factors for children aged 3–19 years (N = 1492). For the purposes of this paper, an analysis of a subsample of adolescents (aged 10–19 years; n = 897) was undertaken. Results: Lifetime suicidality in this study was 6.1% (95% CI, 4.6%–7.9%). Conclusions: Factors significantly associated with suicidality included mental disorder, the ecological factor district of residence, factors suggestive of low socioeconomic status, and disadvantaged childhood experiences.


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