scholarly journals Pattern of ovulation in the East African root rat (Tachyoryctes splendens) from Tanzania: induced or spontaneous ovulator?

2016 ◽  
Vol 94 (5) ◽  
pp. 345-351 ◽  
Author(s):  
Jestina V. Katandukila ◽  
Nigel C. Bennett
Keyword(s):  
East Africa ◽  
Physical Contact ◽  
Seasonal Reproduction ◽  
Subterranean Rodents ◽  
East African ◽  
Subterranean Rodent ◽  
Adult Females ◽  
Experimental Treatments ◽  
Cervical Stimulation ◽  
Ovarian Cyclicity

The East African root rat (Tachyoryctes splendens (Rüppell, 1835)) is a solitary subterranean rodent that exhibits a marked seasonal reproduction linked to the bimodal rainfall pattern of East Africa. The current study sets out to determine whether the East African root rat is an induced or spontaneous ovulator. Five wild caught adult females were monitored noninvasively for ovarian cyclicity by measuring urinary progesterone every 2 days over a period of 120 days. Females were subjected to three different experimental treatments, namely, initially singly housed or control (C), nonphysical contact with a male (NPC), and physical contact with a vasectomised male (PC), respectively. The concentration of urinary progesterone was higher during PC than during either NPC or C. The act of coitus appears to be necessary for ovulation to occur in the females. The male East African root rats were found to possess epidermal spines on the penis that can be used to bring about cervical stimulation during coitus. The spines result in the induction of ovulation as has been proposed for other solitary subterranean rodents. The findings from the female progesterone profiles and the assessment of penile morphology suggest that the female East African root rat is an induced ovulator stimulated by penile intromission during coitus.

scholarly journals Pattern of ovulation in an ancient, solitary mole-rat lineage: Heliophobius argenteocinereus emini from Tanzania

2017 ◽  
Vol 95 (10) ◽  
pp. 737-743 ◽  
Author(s):  
Jestina V. Katandukila ◽  
Mungo K. Ngalameno ◽  
Georgies F. Mgode ◽  
Armanda D.S. Bastos ◽  
Nigel C. Bennett
Keyword(s):  
East Africa ◽  
Physical Contact ◽  
Seasonal Breeding ◽  
Progesterone Concentration ◽  
Subterranean Rodent ◽  
Mole Rat ◽  
The Family ◽  
Experimental Treatments ◽  
Cervical Stimulation ◽  
Ovarian Cyclicity

The genus Heliophobius Peters, 1846 is an ancient subterranean rodent lineage within the family Bathyergidae that displays seasonal breeding over a broad geographical range. In East Africa, reproduction in these solitary mole-rats has been shown to coincide with the long rains, but it is not clear whether the silvery mole-rat subspecies Heliophobius argenteocinereus emini Noack, 1894 from Tanzania is an induced or spontaneous ovulator. To address this, urinary progesterone was measured every second day over a period of 132 days in six wild-caught females subjected to three sequential experimental treatments. In the first, control (C) treatment, females were housed singly for a period of 44 days, following which nonphysical contact (NPC) with a vasectomised male and then physical contact (PC) with the same vasectomised male occurred in each of the subsequent 44-day treatments. Noninvasive monitoring of ovarian cyclicity confirmed that mean urinary progesterone concentration was higher during PC than during either NPC or C, despite the fact that the males were vasectomised and incapable of fertilising the females. Examination of penile morphology revealed that males possess epidermal projections on the glans penis, which probably bring about cervical stimulation during coitus. These findings together with the female progesterone profiles imply the species is an induced ovulator stimulated by penile intromission.

The War of Legs

Transfers ◽  
2015 ◽  
Vol 5 (2) ◽  
pp. 102-120
Author(s):  
Michael Pesek
Keyword(s):  
World War I ◽  
Medical Care ◽  
East Africa ◽  
Transport Infrastructure ◽  
World War ◽  
East African ◽  
Colonial State ◽  
History Of ◽  
Main Factors ◽  
Belgian Congo

This article describes the little-known history of military labor and transport during the East African campaign of World War I. Based on sources from German, Belgian, and British archives and publications, it considers the issue of military transport and supply in the thick of war. Traditional histories of World War I tend to be those of battles, but what follows is a history of roads and footpaths. More than a million Africans served as porters for the troops. Many paid with their lives. The organization of military labor was a huge task for the colonial and military bureaucracies for which they were hardly prepared. However, the need to organize military transport eventually initiated a process of modernization of the colonial state in the Belgian Congo and British East Africa. This process was not without backlash or failure. The Germans lost their well-developed military transport infrastructure during the Allied offensive of 1916. The British and Belgians went to war with the question of transport unresolved. They were unable to recruit enough Africans for military labor, a situation made worse by failures in the supplies by porters of food and medical care. One of the main factors that contributed to the success of German forces was the Allies' failure in the “war of legs.”

scholarly journals Crustal variability along the rifted/sheared East African margin: a review

2021 ◽  
Vol 41 (2) ◽  
Author(s):  
Maren Vormann ◽  
Wilfried Jokat
Keyword(s):  
East Africa ◽  
Shear Zone ◽  
Structural Changes ◽  
The South ◽  
East African ◽  
The North ◽  
Rifted Margins ◽  
Continental Block ◽  
Seismic Lines ◽  
Southeastern Madagascar

AbstractThe East African margin between the Somali Basin in the north and the Natal Basin in the south formed as a result of the Jurassic/Cretaceous dispersal of Gondwana. While the initial movements between East and West Gondwana left (oblique) rifted margins behind, the subsequent southward drift of East Gondwana from 157 Ma onwards created a major shear zone, the Davie Fracture Zone (DFZ), along East Africa. To document the structural variability of the DFZ, several deep seismic lines were acquired off northern Mozambique. The profiles clearly indicate the structural changes along the shear zone from an elevated continental block in the south (14°–20°S) to non-elevated basement covered by up to 6-km-thick sediments in the north (9°–13°S). Here, we compile the geological/geophysical knowledge of five profiles along East Africa and interpret them in the context of one of the latest kinematic reconstructions. A pre-rift position of the detached continental sliver of the Davie Ridge between Tanzania/Kenya and southeastern Madagascar fits to this kinematic reconstruction without general changes of the rotation poles.

scholarly journals Epidemic malaria and warmer temperatures in recent decades in an East African highland

2010 ◽  
Vol 278 (1712) ◽  
pp. 1661-1669 ◽  
Author(s):  
David Alonso ◽  
Menno J. Bouma ◽  
Mercedes Pascual
Keyword(s):  
Climate Change ◽  
East Africa ◽  
Nonlinear Response ◽  
Climate Change Impacts ◽  
Human Model ◽  
Recent Past ◽  
East African ◽  
Highly Nonlinear ◽  
The Impact

Climate change impacts on malaria are typically assessed with scenarios for the long-term future. Here we focus instead on the recent past (1970–2003) to address whether warmer temperatures have already increased the incidence of malaria in a highland region of East Africa. Our analyses rely on a new coupled mosquito–human model of malaria, which we use to compare projected disease levels with and without the observed temperature trend. Predicted malaria cases exhibit a highly nonlinear response to warming, with a significant increase from the 1970s to the 1990s, although typical epidemic sizes are below those observed. These findings suggest that climate change has already played an important role in the exacerbation of malaria in this region. As the observed changes in malaria are even larger than those predicted by our model, other factors previously suggested to explain all of the increase in malaria may be enhancing the impact of climate change.

Social and cultural integration: a case study of the East African Hadramis

Africa ◽  
1989 ◽  
Vol 59 (2) ◽  
pp. 185-195 ◽  
Author(s):  
Françoise Le Guennec-Coppens
Keyword(s):  
East Africa ◽  
Cultural Integration ◽  
East African ◽  
Extended Study ◽  
Opening Paragraph

Opening ParagraphAs one goes through the numerous publications concerning East Africa, it becomes apparent that certain subjects have rarely been approached, having been neglected or even totally ignored. Such is the case concerning the problems linked with the Hadrami diaspora, the extended study of which—apart from a few notable exceptions—has not yet aroused the interest of historians or the curiosity of anthropologists.

Defamation in East Africa

1973 ◽  
Vol 17 (1) ◽  
pp. 66-93 ◽  
Author(s):  
R. W. Hodgin
Keyword(s):  
East Africa ◽  
East African ◽  
African Countries ◽  
English Law

The purpose of this article is to review the application of the English law of defamation in the East African countries (Uganda, Kenya, Tanzania) and to assess the possible contribution of the Kenya Defamation Act, 1970.

scholarly journals EAC – an Answer for Regional Problems or Failed Solutions in East Africa?

Politeja ◽  
2019 ◽  
Vol 15 (56) ◽  
pp. 267-277
Author(s):  
Anna Cichecka
Keyword(s):  
East Africa ◽  
Regional Identity ◽  
East African ◽  
Integration Model ◽  
East African Community ◽  
Intergovernmental Cooperation ◽  
African Community ◽  
Regional Problems ◽  
Common Policy

One of the definitions states that regionalism means a common policy or project aimed at increasing informal links and economic, political and social transactions which strengthen integration processes, intensify intergovernmental cooperation and create regional identity among the community. According to the above, it was assumed that firstly, states in a group are stronger and more effective and secondly, that regionalism and regionalization may be regarded as a way to solve some regional problems and to contribute to the development of individual states. This narrative became especially attractive for underdeveloped and dysfunctional regions as it offered an opportunity for changes. As a result, a quantitative increase in regional initiatives started. The article is dedicated to the integration processes in the East Africa region. The main aim of the paper is to examine the situation in East Africa, regarding the role that the East African Community has played in this area. Moreover, an attempt has been made to analyze the integration model adopted by the organization and find out if the EAC is able to solve the main regional problems or rather to propose a failed solution and maintain dysfunctional patterns in the organization.

scholarly journals Analysis of main risk factors contributing to obesity in the region of East Africa: meta-analysis

2020 ◽  
Vol 20 (1) ◽  
pp. 248-256
Author(s):  
Lenka Mařincová ◽  
Simona Šafaříková ◽  
Radka Cahlíková
Keyword(s):  
Risk Factors ◽  
East Africa ◽  
Meta Analysis ◽  
Obesity Prevalence ◽  
East African ◽  
African Region ◽  
African Countries ◽  
Chi Square ◽  
Chi Square Test ◽  
Risk Ratios

Background: Over a few decades obesity has become a major global health problem. Its prevalence worldwide has more than doubled since 1980. The situation is expected to worsen in the future, especially in the developing countries that experience nutrition transition due to economic growth. It contributes to reduction in malnutrition which supports an increase in obesity prevalence. Objectives: The aim of this study was to analyse the predictors of obesity in the region of East Africa. Methods: Meta-analysis of existing studies was used in order to find the different risk factors and their significance in obesity development. Data extracted from 16 published academic research articles described the situation in East African countries. The significance of the effect of each variable was tested by means of an asymptotic chi-square test, or Fisher's exact (factorial) test and the risk ratios were calculated. Results: Based on the chi-square test and the risk ratios of the aggregated data, three risk factors were found to be significant in the development of obesity – gender, type of residence and socio-economic status. In East African countries, women are significantly more likely to be obese. Living in an urban area and socioeconomic status are also positively associated with obesity. Because of insufficient data three other risk factors did not prove to be of any significance – alcohol consumption, smoking and education level. Conclusion: Conclusions of this meta-analysis confirm world trends but we also found results that are not in line with them (e.g. education). This meta-analysis confirms the huge existing research gap concerning obesity predictors in the East African region. Keywords: Obesity; meta-analysis; East Africa. 

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