scholarly journals Peeling Back the Layers: the Complex Dynamics Shaping the Evolution of the Ledebouriinae (Scilloideae, Asparagaceae)

2020 ◽  
Author(s):  
Cody Coyotee Howard ◽  
Andrew A. Crowl ◽  
Timothy S. Harvey ◽  
Nico Cellinese
Keyword(s):  
Complex Dynamics ◽  
Incomplete Lineage Sorting ◽  
Sub Saharan Africa ◽  
Lineage Sorting ◽  
East African ◽  
Historical Factors ◽  
Clade B ◽  
Phylogenetic Framework ◽  
Sub Saharan ◽  
Probe Set

AbstractThe Ledebouriinae (Scilloideae, Asparagaceae) are a widespread group of bulbous geophytes found predominantly throughout seasonal climates in sub-Saharan Africa, with a handful of taxa in Madagascar, the Middle East, India and Sri Lanka. An understanding of the phylogenetic relationships within the group have been historically difficult to reconstruct, however. Here, we provide the first phylogenomic perspective into the Ledebouriinae. We use this renewed phylogenetic framework to hypothesize historical factors that have resulted in the topology recovered. Using the Angiosperms353 targeted enrichment probe set, we consistently recovered four major clades (i.e. two Ledebouria clades, Drimiopsis, and Resnova). The two Ledebouria clades closely align with geography, either consisting almost entirely of sub-Saharan African taxa (Ledebouria Clade A), or East African and non-African taxa (Ledebouria Clade B). Our results also suggest that the Ledebouriinae underwent a rapid radiation leading to rampant incomplete lineage sorting. [Asparagaceae; Drimiopsis; geophytes; Ledebouria; monocots; Resnova; Scilloideae.]

scholarly journals First Report of East African Cassava Mosaic Begomovirus in Nigeria

Plant Disease ◽  
1999 ◽  
Vol 83 (4) ◽  
pp. 398-398 ◽  
Author(s):  
F. O. Ogbe ◽  
G. I. Atiri ◽  
D. Robinson ◽  
S. Winter ◽  
A. G. O. Dixon ◽  
...  
Keyword(s):  
Central Africa ◽  
Mosaic Disease ◽  
Sub Saharan Africa ◽  
Cassava Mosaic Disease ◽  
Enzyme Linked Immunosorbent Assay ◽  
East African ◽  
African Countries ◽  
Manihot Esculenta Crantz ◽  
Cross River State ◽  
Sub Saharan

Cassava (Manihot esculenta Crantz) is an important food crop in sub-Saharan Africa. One of the major production constraints is cassava mosaic disease caused by African cassava mosaic (ACMV) and East African cassava mosaic (EACMV) begomoviruses. ACMV is widespread in its distribution, occurring throughout West and Central Africa and in some eastern and southern African countries. In contrast, EACMV has been reported to occur mainly in more easterly areas, particularly in coastal Kenya and Tanzania, Malawi, and Madagascar. In 1997, a survey was conducted in Nigeria to determine the distribution of ACMV and its strains. Samples from 225 cassava plants showing mosaic symptoms were tested with ACMV monoclonal antibodies (MAbs) in triple antibody sandwich enzyme-linked immunosorbent assay (1). Three samples reacted strongly with MAbs that could detect both ACMV and EACMV. One of them did not react with ACMV-specific MAbs while the other two reacted weakly with such MAbs. With polymerase chain reaction (2), the presence of EACMV and a mixture of EACMV and ACMV in the respective samples was confirmed. These samples were collected from two villages: Ogbena in Kwara State and Akamkpa in Cross River State. Co-infection of some cassava varieties with ACMV and EACMV leads to severe symptoms. More importantly, a strain of mosaic geminivirus known as Uganda variant arose from recombination between the two viruses (2). This report provides evidence for the presence of EACMV in West Africa. References: (1) J. E. Thomas et al. J. Gen. Virol. 67:2739, 1986. (2) X. Zhou et al. J. Gen. Virol. 78:2101, 1997.

scholarly journals Volcanic activity and hazard in the East African Rift Zone

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Juliet Biggs ◽  
Atalay Ayele ◽  
Tobias P. Fischer ◽  
Karen Fontijn ◽  
William Hutchison ◽  
...  
Keyword(s):  
Volcanic Activity ◽  
East African Rift ◽  
Volcanic Hazards ◽  
Crisis Response ◽  
Sub Saharan Africa ◽  
Rift System ◽  
East African Rift System ◽  
East African ◽  
Sub Saharan ◽  
African Rift

AbstractOver the past two decades, multidisciplinary studies have unearthed a rich history of volcanic activity and unrest in the densely-populated East African Rift System, providing new insights into the influence of rift dynamics on magmatism, the characteristics of the volcanic plumbing systems and the foundation for hazard assessments. The raised awareness of volcanic hazards is driving a shift from crisis response to reducing disaster risks, but a lack of institutional and human capacity in sub-Saharan Africa means baseline data are sparse and mitigating geohazards remains challenging.

Tanzania: Civil–Military Relations and Nationalism

2020 ◽  
Author(s):  
Daniel G. Zirker
Keyword(s):  
Civil Society ◽  
Military Training ◽  
Sub Saharan Africa ◽  
East African ◽  
African Countries ◽  
Civil Military Relations ◽  
Sub Saharan ◽  
The 1960S ◽  
Military Relations ◽  
The Military

Why have there been no successful military interventions or civil wars in Tanzania’s nearly 60 years of independence? This one historical accomplishment, by itself striking in an African context, distinguishes Tanzania from most of the other post-1960 independent African countries and focuses attention on the possibilities and nature of successful civil–military relations in sub-Saharan Africa. Contrary to most civil–military relations theory, rather than isolating the military in order to achieve civilian oversight, Tanzania integrated the military, the dominant political party, and civil society in what one observer called a combination of “political militancy” and “antimilitarism,” somewhat akin, perhaps, to the Chinese model. China did provide intensive military training for the Tanzanians beginning in the 1960s, although this could in no way have been expected to ensure successful integration of the military with civil society, nor could it ensure peaceful civil–military relations. Eight potentially causal and overlapping conditions have been outlined to explain this unique absence of civil–military strife in an African country. Relevant but admittedly partial explanations are: the largely salutary and national developmental role of the founding president, Julius Nyerere; the caution and long-term fear of military intervention engendered by the 1964 East African mutinies; Tanzania’s radical foreign policy as a Frontline State; its ongoing territorial disputes with Uganda and Malawi; concerted efforts at coup-proofing through the co-opting of senior military commanders; and the country’s striking ethnic heterogeneity, in which none of the 125 plus ethnolinguistic tribes had the capacity to assume a hegemonic dominance. Each factor has a role in explaining Tanzania’s unique civil–military history, and together they may comprise a plausible explanation of the over 50 years of peaceful civil–military relations. They do not, however, provide a hopeful prognosis for future civil–military relations in a system that is increasingly challenging the dominant-party state, nor do they account for Tanzania’s subsequent democratic deficit.

scholarly journals COVID-19 Response in Sub-Saharan Africa: Lessons From Uganda

2020 ◽  
Vol 14 (3) ◽  
pp. e46-e48 ◽  
Author(s):  
Ivan Lumu
Keyword(s):  
Decision Making ◽  
Ebola Virus ◽  
Virus Disease ◽  
Sub Saharan Africa ◽  
Disease Spread ◽  
East African ◽  
Limited Disease ◽  
African Countries ◽  
Response Team ◽  
Sub Saharan

ABSTRACTThe prolongation of the Ebola epidemic may have allowed some countries to prepare and respond to the coronavirus disease (COVID-19) outbreak. In Uganda, the surveillance structure built for Ebola virus disease (EVD) has become a pillar in the COVID-19 response. This testing and tracing apparatus has limited disease spread to clusters with zero mortality compared with the neighboring East African countries. As more sub-Saharan countries implement social distancing to contain the outbreak, the interventions should be phased and balanced with health risk and socioeconomic situation. However, having a decision-making matrix would better guide the response team. These initial lessons from EVD-experienced Uganda may be helpful to other countries in the region.

scholarly journals Access to improved sanitation facilities in low-income informal settlements of East African cities

2014 ◽  
Vol 5 (1) ◽  
pp. 89-99 ◽  
Author(s):  
K. Okurut ◽  
R. N. Kulabako ◽  
P. Abbott ◽  
J. M. Adogo ◽  
J. Chenoweth ◽  
...  
Keyword(s):  
Low Income ◽  
Urban Areas ◽  
Informal Settlement ◽  
Informal Settlements ◽  
Sub Saharan Africa ◽  
East African ◽  
Basic Sanitation ◽  
Improved Sanitation ◽  
Joint Monitoring ◽  
Sub Saharan

Throughout Africa, the population in urban areas is increasing rapidly, often exceeding the capacity and the resources of the cities and towns to accommodate the people. In sub-Saharan Africa, the majority of urban dwellers live in informal settlements served by inadequate sanitation facilities. These settlements present unique challenges to the provision of sustainable and hygienic sanitation, and there is insufficient information on access to improved facilities. This paper reports findings of a study undertaken in low-income informal settlements using a mixed methods approach to assess access to sanitation and identify the barriers to household uptake of improved sanitation facilities. More than half of the respondents (59.7%) reported using sanitation facilities that are included in the WHO/UNICEF Joint Monitoring Programme definition of improved sanitation. However, a high proportion of these facilities did not provide access to basic sanitation. Less than 5% of all the respondents did not report problems related to sustainable access to basic sanitation. The findings highlight the urgent need to develop specific and strategic interventions for each low-income informal settlement, to upscale the sustainable access and use of improved sanitation in urban centres.

Proceedings of the African Pathologists Summit; March 22–23, 2013; Dakar, Senegal: A Summary

2014 ◽  
Vol 139 (1) ◽  
pp. 126-132 ◽  
Author(s):  
African Pathologists' Summit Working Groups
Keyword(s):  
Clinical Pathology ◽  
West African ◽  
Sub Saharan Africa ◽  
East African ◽  
Laboratory Service ◽  
Medical College ◽  
The Status ◽  
Sub Saharan ◽  
American Society ◽  
International Academy

Context This report presents the proceedings of the African Pathologists Summit, held under the auspices of the African Organization for Research and Training in Cancer. Objectives To deliberate on the challenges and constraints of the practice of pathology in Sub-Saharan Africa and the avenues for addressing them. Participants Collaborating organizations included the American Society for Clinical Pathology; Association of Pathologists of Nigeria; British Division of the International Academy of Pathology; College of Pathologists of East, Central and Southern Africa; East African Division of the International Academy of Pathology; Friends of Africa–United States and Canadian Academy of Pathology Initiative; International Academy of Pathology; International Network for Cancer Treatment and Research; National Cancer Institute; National Health and Laboratory Service of South Africa; Nigerian Postgraduate Medical College; Royal College of Pathologists; West African Division of the International Academy of Pathology; and Faculty of Laboratory Medicine of the West African College of Physicians. Evidence Information on the status of the practice of pathology was based on the experience of the participants, who are current or past practitioners of pathology or are involved in pathology education and research in Sub-Saharan Africa. Consensus Process The deliberations were carried out through presentations and working discussion groups. Conclusions The significant lack of professional and technical personnel, inadequate infrastructure, limited training opportunities, poor funding of pathology services in Sub-Saharan Africa, and their significant impact on patient care were noted. The urgency of addressing these issues was recognized, and the recommendations that were made are contained in this report.

scholarly journals Fifty shades of red: Lost or threatened bryophytes in Africa

Bothalia ◽  
2019 ◽  
Vol 49 (1) ◽  
Author(s):  
Jacques Van Rooy ◽  
Ariel Bergamini ◽  
Irene Bisang
Keyword(s):  
Plant Conservation ◽  
Red List ◽  
Global Strategy ◽  
Sub Saharan Africa ◽  
East African ◽  
Red Lists ◽  
Sub Saharan ◽  
Regional Red Lists ◽  
Specialist Group ◽  
Threatened Bryophytes

Background: A Red List of threatened bryophytes is lacking for Africa. The International Union for Conservation of Nature (IUCN) Species Survival Commission (SSC) Bryophyte Specialist Group has recently launched the ‘Top 10 Initiative’ to identify the 10 species on each continent that are at highest risk of extinction.Objectives: The main aim of this paper was to highlight some of the lost or strongly threatened bryophyte species in sub-Saharan Africa and the East African islands and to draw up a Top 10 list for Africa.Method: Lost or threatened species have been identified with the help of experts on the bryoflora of Africa, global and regional Red Lists and taxonomic literature. Each species on this candidate list is discussed at the hand of its taxonomy, distribution, habitat, threat and current global or regional Red List status as far as previously assessed.Results: Fifty bryophyte species, representing 40 genera and 23 families, have been identified as Top 10 candidates. Of these, 29 are endemic to Africa and 21 are restricted to the East African islands. The majority of the candidate species occur in one of eight ‘biodiversity hotspots’ with most species (19) in the Madagascar and the Indian Ocean Islands hotspot.Conclusion: This is the first list of lost or threatened bryophytes for Africa and the first Top 10 list of the IUCN Bryophyte Specialist Group. It represents an important step towards regional and global Red List assessment of bryophytes, thus meeting the targets of the Updated Global Strategy for Plant Conservation 2011–2020 and priorities of The Shenzhen Declaration on Plant Sciences.

scholarly journals Rapid ecological specialization despite constant population sizes

2018 ◽  
Author(s):  
Andrinajoro R Rakotoarivelo ◽  
Yoshan Moodley
Keyword(s):  
Incomplete Lineage Sorting ◽  
Molecular Dating ◽  
Sub Saharan Africa ◽  
Dna Polymorphisms ◽  
Secondary Contact ◽  
12S Rrna ◽  
Ecological Specialization ◽  
Lineage Sorting ◽  
Mt Dna ◽  
Data Set

Background. The bushbuck, Tragelaphus scriptus, is the most widespread and ecologically diverse ungulate species complex within the spiral-horned antelopes, occurring in approximately 73% of the total land area of sub-Saharan Africa. This species was found to consist of two genetically divergent lineages based on the mitochondrial (mt)DNA control region. One lineage inhabited the north-western half of the African continent (T. scriptus) while the other lineage (T. sylvaticus) was found in the south-eastern half. The complex was also found to comprise an unprecedented example of 23 phylogenetically distinct groups (‘ecotypes’), with montane and desert phenotypes potentially resulting from convergent evolution. The current study aim to test hypotheses regarding historical demography and adaptation of bushbuck using a higher-resolution framework, with faster evolving nuclear markers(MGF, PRKCI, SPTBN, and THY) as well as three further mitochondrial markers (cytochrome b, 12S rRNA, and 16S rRNA). Methods. Genealogies were reconstructed for the nuclear and mitochondrial data sets and for each gene independently to test the non-monphyly of the bushbuck complexe in a multi loci framework. In addition, we reconstruct the phylogeographic history of the bushbuck complex by a Bayesian discrete phylogeographic approach of our nucDNA data set to investigate its geographic diffusion and ancestral sequence location. Results. We uncovered two evolutionarily divergent lineages and geographically restricted lineages (Sylvaticus and Scriptus) of bushbuck using phylogenetics. Molecular dating indicates that these lineages last shared a common ancestor ∼2.54 million years ago. Summary statistics and analysis of the frequency distributions of DNA polymorphisms do not have any support for expanding population. Both BSPs and EBSPs indicate that the Scriptus and Sylvaticus lineages have remained relatively stable during the last 225-450Kya. Discussion. Both nucDNA and mtDNA support previously findings of two genetically divergent Sylvaticus and Scriptus lineages, despite them coming into secondary contact in several geographic regions. The three mtDNA loci confirmed 15 of the previously defined ecotypes, including those with convergent phenotypes. However, the nuclear tree showed less phylogenetic resolution at the more derived parts of the genealogy, possibly due to incomplete lineage sorting of the slower evolving nuclear genome. The only exception to this was the montane ecotype meneliki of the Ethiopian highlands, which formed a monophyletic group at three of the four nucDNA loci. The independent evolution of this group relative to phenotypically similar montane ecotypes in Africa confirm previously suggestions of convergence within the bushbuck complex.

scholarly journals Fighting non-communicable diseases in East Africa: assessing progress and identifying the next steps

2020 ◽  
Vol 5 (11) ◽  
pp. e003325
Author(s):  
Christian Kraef ◽  
Pamela A Juma ◽  
Joseph Mucumbitsi ◽  
Kaushik Ramaiya ◽  
Francois Ndikumwenayo ◽  
...  
Keyword(s):  
Communicable Disease ◽  
National Policy ◽  
Sub Saharan Africa ◽  
East African ◽  
Policy Makers ◽  
East African Community ◽  
Monitoring Tools ◽  
The Status ◽  
African Community ◽  
Sub Saharan

Sub-Saharan Africa has seen a rapid increase in non-communicable disease (NCD) burden over the last decades. The East African Community (EAC) comprises Burundi, Rwanda, Kenya, Tanzania, South Sudan and Uganda, with a population of 177 million. In those countries, 40% of deaths in 2015 were attributable to NCDs. We review the status of the NCD response in the countries of the EAC based on the available monitoring tools, the WHO NCD progress monitors in 2017 and 2020 and the East African NCD Alliance benchmark survey in 2017. In the EAC, modest progress in governance, prevention of risk factors, monitoring, surveillance and evaluation of health systems can be observed. Many policies exist on paper, implementation and healthcare are weak and there are large regional and subnational differences. Enhanced efforts by regional and national policy-makers, non-governmental organisations and other stakeholders are needed to ensure future NCD policies and implementation improvements.

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