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In the species‐rich genus Impatiens, few natural hybrids are known, even though closely related species often occur sympatrically. In this study, we aim to bridge the gap between micro‐ and macro‐evolution to disentangle pre‐ and postzygotic mechanisms that may prevent hybridization in the Impatiens purpureoviolacea complex from Central Africa. We analyzed habitat types, species distribution, pollination syndromes, pollinator dependency, genome sizes, and chromosome numbers of seven out of the ten species of the complex as well as of one natural hybrid and reconstructed the ancestral chromosome numbers of the complex. Several species of the complex occur in sympatry or geographically very close to each other. All of them are characterized by pre‐ and/or postzygotic mechanisms potentially preventing hybridization. We found four independent polyploidization events within the complex. The only known natural hybrid always appears as single individual and is self‐fertile. But the plants resulting from self‐pollinated seeds often die shortly after first flowering. These results indicate that the investigated mechanisms in combination may effectively but not absolutely prevent hybridization in Impatiens and probably occur in other genera with sympatric species as well. [ABSTRACT FROM AUTHOR]

Sub‐Saharan Africa desperately needs more electricity. Recent years have seen private investment in renewable energy projects breaking through in the region, primarily driven by well‐designed and implemented auction programs. We review three renewable energy auction programs in the region to improve our understanding of the auction design and implementation elements that have enabled this important transition: the South African Renewable Energy Independent Power Producers Procurement Program (REIPPPP); the GET FiT solar facility in Uganda; and the first round of the Scaling Solar program in Zambia. Our analysis shows that a well‐designed and implemented program that adequately deals with risks for both the procuring authorities and investors is able to deliver good investment and price outcomes in sub‐Saharan Africa. This article is categorized under: Photovoltaics > Climate and Environment Energy Policy and Planning > Climate and Environment Photovoltaics > Economics and Policy Energy Policy and Planning > Economics and Policy [ABSTRACT FROM AUTHOR]

Adequate, secure, and competitively priced electricity is vital for powering economic growth and development. Privately funded, independent power producers (IPPs) are now making an important contribution to meeting overall power needs in developing countries, including in Africa. Our aim in this article is to explore what may be learned from Kenya's experience with IPPs and what lessons might be applied to other developing countries. We consider how Kenya's IPPs measure up to their public counterparts in terms of reliability and costs and possibilities for scale-up. Kenya's two decades of experience with power sector reform and IPPs makes it possible to compare changing policies, sector unbundling, regulatory frameworks, planning, and investment over a relatively long period. Kenya is also host to IPPs with different technology bases, which allow for an evaluation of their relative costs and reliability. Finally, the mix of directly negotiated and competitively bid projects facilitates a comparison of procurement practices. While power sector reform in Kenya created an enabling environment for IPPs, probably more important was the development of effective planning, tendering, and contracting capabilities, which attracted investment at competitive prices. The challenge for Kenya and other developing countries is to maintain and sustain these capabilities within clear policies that provide regular opportunities for the private sector to contribute to meeting power deficits. [ABSTRACT FROM AUTHOR]

South Africa's Renewable Energy Independent Power Producer Procurement Program has run four competitive tenders/auctions since 2011, which have seen US$19 billion in private investment, and electricity prices of wind power falling by 46% and solar PV electricity prices by 71%, in nominal terms. Competitive tenders were introduced after an unsuccessful attempt to implement feed-in tariffs. The tenders incorporated standard, nonnegotiable contract documents, including 20-year Power Purchase Agreements and an Implementation Agreement whereby the Government of South Africa back-stops IPP payments by the national utility, Eskom. All of these projects have reached financial close to date and some are already delivering power to the grid. The financing success has been due in part to the requirements for commercial banks to undertake a thorough due diligence of projects prior to bids being offered. The details of the policy package described may be useful for other policy makers in countries developing policies for renewable energy deployment. [ABSTRACT FROM AUTHOR]

Background: Yellow fever (YF) is an acute viral hemorrhagic disease transmitted by Aedes mosquitoes. The causative agent, the yellow fever virus (YFV), is found in tropical and subtropical areas of South America and Africa. Although a vaccine is available since the 1930s, YF still causes thousands of deaths and several outbreaks have recently occurred in Africa. Therefore, rapid and reliable diagnostic methods easy to perform in low-resources settings could have a major impact on early detection of outbreaks and implementation of appropriate response strategies such as vaccination and/or vector control. Methodology: The aim of this study was to develop a YFV nucleic acid detection method applicable in outbreak investigations and surveillance studies in low-resource and field settings. The method should be simple, robust, rapid and reliable. Therefore, we adopted an isothermal approach and developed a recombinase polymerase amplification (RPA) assay which can be performed with a small portable instrument and easy-to-use lyophilized reagents. The assay was developed in three different formats (real-time with or without microfluidic semi-automated system and lateral-flow assay) to evaluate their application for different purposes. Analytical specificity and sensitivity were evaluated with a wide panel of viruses and serial dilutions of YFV RNA. Mosquito pools and spiked human plasma samples were also tested for assay validation. Finally, real-time RPA in portable format was tested under field conditions in Senegal. Conclusion/Significance: The assay was able to detect 20 different YFV strains and demonstrated no cross-reactions with closely related viruses. The RPA assay proved to be a robust, portable method with a low detection limit (<21 genome equivalent copies per reaction) and rapid processing time (<20 min). Results from real-time RPA field testing were comparable to results obtained in the laboratory, thus confirming our method is suitable for YFV detection in low-resource settings. Author Summary: Despite the use of a safe and effective vaccine, yellow fever virus is still causing hundreds of thousands of infections and tens of thousands of deaths every year. The disease is widespread in South America and Africa where several outbreaks have occurred in the past years. As the disease is difficult to distinguish from other illnesses during its early stage, it is necessary to develop reliable, rapid and simple diagnostic methods to confirm YF cases to be able to respond effectively to outbreaks through vaccination and vector control. In this study, we describe the development a diagnostic method for YFV, using an isothermal technology called recombinase polymerase amplification which allows detection of the virus within 20 minutes, using a portable and easy-to-use device. The YFV RPA assay proved to be a specific and sensitive detection method during testing in the laboratory and under field conditions in Senegal. [ABSTRACT FROM AUTHOR]

At home and abroad we face the seemingly intractable problem of fundamentalist ideology, racism, and tribal violence tearing apart the human fabric. Here I propose that paying attention to innate psychological processes can make a difference. I work with individuals and communities suffering the posttraumatic consequences of war and violence in crisis areas of eastern Congo, northern Uganda, South Sudan, and western Kenya. I have observed that unresolved posttraumatic issues lead to intergenerational transmission of trauma, which, in turn, feeds future cycles of war, violence, and discrimination. In the spirit of prevention, it is essential that the international community prioritize attention to the psychological perspectives involved in human rights issues. Here I develop elements of a holistic systems approach to dealing with large-scale posttraumatic crises afflicting communities and the culture at large. I pay special attention to cultural interfaces and what C. G. Jung called thecultural dimensionof the psyche. In fieldwork I blend digital photography and psychotherapeutic approaches to transcend personal and cultural layers of reference and rekindle the struggle of giving birth to one's future. In a Cameras without Borders workshop a survivor of sexual violence in the eastern Congo said, “The camera is pregnant.” Such metaphors function to shatter limitations of the traumatized mind. Dissociation is the hallmark of psychological trauma as well as of the fundamentalist condition. I view developing a capacity for curiosity and mutuality not only as central to the treatment of trauma but also as an antidote to the ills and sclerosis of a fundamentalist mindset, which is the source of much human suffering. Curiosity inspires action, and mutuality invites caring about social justice and peace. [ABSTRACT FROM AUTHOR]

Two new species of Syncesia are described, which differ from all other species of the genus by having more than 3-septate ascospores. Syncesia afromontana is characterized by a byssoid thallus and 7-septate ascospores, and is known only from the type locality in the Nyungwe Forest in Rwanda where it might be endemic. Syncesia madagascariensis is characterized by a crustose thallus and 5-septate ascospores, and is known only from the type locality in a montane forest in central Madagascar. [ABSTRACT FROM AUTHOR]

Abstract  The paper reports the first detection of besnoitiosis of cattle in Germany. Just 2 years after the first appearance of the African Bluetongue disease (BTD) of cattle in Central Europe, another African agent of disease has arrived in Germany. While it was proven that the BTD virus was transmitted (after its first appearance) by endemic midges of the genus Culicoides (C. obsoletus, C. pulicaris), nothing is known, how the infectious stages of Besnoitia besnoiti—a member of the so-called cyst-forming coccidia—found their way to a herd in Southern Germany. The infected animals showed all characteristic clinical symptoms of besnoitiosis such as hyposclerodermia, hyperkeratosis, alopecia, and whitish tissue cysts in subcutaneous tissues as well as in the cornea. These cysts had diameters of up to 3 mm and consisted of a dense outer layer (=secondary cyst wall), which surrounded a host cell, that had been enormously enlarged by an inner parasitophorous vacuole containing thousands of 7–9 × 2 μm sized, banana-shaped cyst merozoites (=cystozoites, bradyzoites).Their fine structure was identical to that of published stages of B. besnoiti. During cyst development, the nucleus of the host cell had been hypertrophied and had apparently undergone several divisions, since many flattened, but very large nuclei were seen in light and electron microscopy. Thus, this study proves the arrival of another serious agent of disease of ruminants in Central Europe—a fact which is especially important, since in this species, there is neither information on the way of transmission from animal to animal nor exists concrete information on an efficacious therapy or on the modalities of its import into Germany. [ABSTRACT FROM AUTHOR]

This study analyses the outcomes of African independent power projects (IPPs). Nearly 40 such projects have taken root to date, concentrated mainly in 8 countries. More balanced outcomes are perceived in North Africa than across sub-Saharan Africa (SSA), for reasons linked to more attractive investment environments, more robust policy frameworks, fewer planning mishaps, abundant low-cost fuel and secure fuel contracts as well as credit enhancements such as sovereign guarantees. With few exceptions, these elements were absent in SSA, where the role of development finance institutions and the strategic management of projects seem more important. [ABSTRACT FROM AUTHOR]

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This paper narrates the experience of Tunisia's two independent power projects (IPPs), which were developed as part of the country's electricity supply industry reforms. Although both plants use gas as their primary energy, the two projects vary in size, fuel supply arrangements, power purchase agreements and the legal frameworks under which they were developed. With Rades II, the country's first IPP, loans have been indexed to multiple currencies and, to date, charges to the utility remain affordable. This is partly due to the fact that the Tunisian dinar (TND) has been relatively stable since the inception of the contracts - unlike in other emerging economies where currency devaluations have resulted in significant increases in charges. With El Biban, the country's second IPP, fuel supply problems have interrupted production for extended periods, impacting on overall plant performance and revenue. Although the loss in revenue is threatening the financial viability of the plant, it does not have a significant impact on the off-taker and national utility for the following reason. El Biban represents less than 1 per cent of the country's installed capacity with no guaranteed availability in terms of its contract with the off-taker. Still the plant is crucial in understanding Tunisia's overall experience as well as particularly relevant to other countries throughout Africa, such as Nigeria and Tanzania, which have developed power plants as part of a larger gas infrastructure project. [ABSTRACT FROM AUTHOR]

The urge of captive birds to migrate manifests itself in seasonally occurring restlessness, termed "Zugunruhe." Key insights into migration and an endogenous basis of behavior are based on Zugunruhe of migrants but have scarcely been tested in nonmigratory birds. We recorded Zugunruhe of African stonechats, small passerine birds that defend year-round territories and have diverged from northern migrants at least 1 million years ago. We demonstrate that Zugunruhe is a regular feature of their endogenous program, one that is precisely timed by photoperiod. These results extend ideas of programs for periodic movement to include nonmigratory birds. Such programs could be activated when movements become necessary, in line with observed fast changes and high flexibility of migration. Attention to Zugunruhe of resident birds promises new insights into diverse and dynamic migration systems and enhances predictions of avian responses to global change. [ABSTRACT FROM AUTHOR]

Maximum likelihood analyses based on the internal transcribed spacer region of nuclear ribosomal DNA and the chloroplast protein coding gene rps4 were conducted to investigate phylogenetic relationships among species of Plagiochila and to reconstruct the ranges of natural species groups within the genus. Based on the results of the molecular analyses and on morphological evidence, the tropical African species of Plagiochila are assigned to the sections Arrectae, Cucullatae, Hylacoetes, Rutilantes, Vagae, and the new sect. Africanae (P. barteri, P. colorans). With the exception of Africanae, all sections possess intercontinental ranges; their centers of diversity are in the tropics. Clade and species diversity in Africa is lower than in other parts of the tropics and may reflect drought periods of the Pleistocene. Intercontinental ranges at specific level exist between tropical America and Africa whereas similarities between tropical Asia and Africa were only recovered at the sectional level. ITS sequence sets were used to test the monophyly of species with intercontinental ranges and to explore the development of the Afro-American range of P. boryana. A well supported clade with accessions of P. boryana from Bolivia and Uganda is nested in the robust neotropical Hylacoetes. This topology and the low genetic distance of the different P. boryana accessions provide some evidence for long-range dispersal of P. boryana eastwards across the Atlantic, originating from the Neotropics. An African origin of the Vagae clade which includes neotropical and paleotropical taxa is suggested by the clustering of accessions from the East African Islands at the base of this clade. In addition, the presented data support the hypothesis of several switches from Africa to Asia and vice versa. A derived clade within Vagae includes accessions from the African mainland and the Neotropics. Our results seem to indicate that the extant tropical African Plagiochila flora is a mixture of old elements and rather recent immigrants. [ABSTRACT FROM AUTHOR]

The Benguela upwelling system in the subtropical Southeast Atlantic is subject to dramatic interannual fluctuations sometimes termed ‘Benguela Nin˜o’ events. The South Atlantic Anticyclone (SAA) is assumed to be the responsible climatic ‘activity centre’ for the south-east trade winds driving the upwelling processes along the Namibian and South-west African coasts. Air temperature and humidity signals of this region, modulated by upwelling-controlled sea surface temperature (SST), are carried by the trades towards St. Helena Island. The island’s 1893–1999 century-long monthly weather records of temperature, pressure and rainfall have been assembled and homogenized. They exhibit trends for decreasing precipitation (10 mm/100 year), increasing air temperature (0.9 °C/100 year), and decreasing air pressure (0.6 hPa/100 year). Their first empirical orthogonal eigenfunction (EOF) covers 46% of the total variance; its associated temporal coefficient is proposed as a ‘St. Helena Island Climate Index (HIX)’. Austral winter HIX has a 42% correlation with a remotely sensed SST-derived Benguela upwelling index, called intense Benguela upwelling, for the time period 1982–1999. Not yet identified Benguela Nin˜os (1895, 1905, 1912, 1916, 1946) and years of strong Benguela upwelling (1911, 1922, 1967, 1976) are newly suggested by the HIX. [Copyright &y& Elsevier]

Equatorial stonechats (Saxicola torquata axillaris) in Africa are seasonal breeders like their temperate-zone conspecifics (S.t. rubicola). Their annual cycle in gonadal size and function is controlled by an endogenous circannual rhythmicity that has been shown to run for up to 10 years in a constant equatorial photoperiod under laboratory conditions, with a period deviating from 12 months. In nature, however, this rhythm is synchronized with the actual year. Because photoperiod is essentially constant at the equator, it is likely that other environmental factors act as zeitgebers. The authors test whether food availability affects reproductive cycles of free-living East African stonechats. The authors offered supplemental food to the birds 2 months before the regular onset of the breeding season. Supplementally fed males started to sing and display earlier than males of control pairs that did not receive extra food. Although the supplemented food advanced the onset of the breeding season in the pairs that were fed, the onset of the postnuptial molt following the breeding season was not correspondingly shifted. Furthermore, in the year following the experiment, all pairs initiated breeding at the same time. The authors conclude that food availability does not act as a zeitgeber, but rather as a factor that modifies the timing of reproduction without affecting the underlying rhythmicity. The authors propose that this is adaptive under environmental conditions that are relatively constant within a given year but may vary considerably between years. The zeitgeber synchronizing the endogenous rhythmicity remains to be identified. [ABSTRACT FROM AUTHOR]

Studies the amplitude of a photoperiod cycle to African stonechat, saxicola torquata axillaris. Goals of the study; Comparison of the responses of the African birds with those of conspecifics from Europe; Results of the study.

Background: Circulating iron is normally bound to transferrin. Non-transferrin-bound iron (NTBI) has been described in most forms of iron overload, but has not been studied in African dietary iron overload. This abnormal iron fraction is probably toxic, but this has not been demonstrated. Methods: High-pressure liquid chromatography was used to assay serum NTBI in 25 black African subjects with iron overload documented by liver biopsy and in 170 relatives and neighbours. Levels of NTBI were correlated with indirect measures of iron status and conventional liver function tests. Results: Non-transferrin-bound iron (> 2 μmol/L) was present in 43 people, 22 of patients of whom underwent liver biopsy and 21 relatives and neighbours. All but four of these had evidence of iron overload on the basis of either liver biopsy or elevated transferrin and serum ferritin concentrations. Among all 195 subjects, the presence of NTBI in serum was independently related to elevations in alanine and aspartate aminotransferase activity and bilirubin concentration. This relationship between serum NTBI and hepatic dysfunction was confirmed in the subgroup of 25 subjects with iron overload documented by liver biopsy. Non-transferrin-bound iron correlated significantly with elevations in alanine and aspartate aminotransferase activities after adjustment for hepatic iron grades, inflammation and diet. Conclusions: Non-transferrin-bound iron was found to be commonly present in African patients with dietary iron overload and to correlate with transferrin saturation and serum ferritin concentration. The independent relationship between NTBI and elevated liver function tests suggests that it may be part of a pathway leading to hepatic injury. [ABSTRACT FROM AUTHOR]

Background: In response to the recent publication "Is onchocerciasis elimination in Africa feasible by 2025: a perspective based on lessons learnt from the African control programmes" by Dadzie et al., it is important to clarify and highlight the positive and unequivocal research and operational contributions from the American experience towards the worldwide elimination of human onchocerciasis (river blindness). Main text: The strategies of twice or more rounds of mass drug administration (MDA) of ivermectin per year, as well as the use of OV-16 serology have allowed four American countries to be verified by World Health Organization to have eliminated transmission of Onchocerca volvulus, the etiological agent. These advances were also implemented in Sudan and Uganda; currently, both are the only African countries where ivermectin MDA was safely stopped in several transmission zones. Conclusions: Programmatic treatment and evaluation approaches, pioneered in the Americas, are the most efficient among the existing tools for elimination, and their broader use could catalyze the successful elimination of this disease in Africa. [ABSTRACT FROM AUTHOR]

The article discusses the progress toward the global eradication of the parasitic infection dracunculiasis from January 2008 to June 2009. The effort was started in 1986 when the World Health Assembly (WHA) called for the eradication of the disease, which is estimated to affect 3.5 million people. By the end of December 2008, the infection was endemic to six African countries, including Ethiopia, Ghana and Mali. Ways in which dracunculiasis can be prevented are given, such as treating contaminated water and providing safe water from borehole or hand-dug wells. The number of cases and the number of villages reporting dracunculiasis cases were reduced by 38% during the said period.