1,951 research outputs found

    Microfinance Institutions in Nigeria

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    The advocation of micro – financing was triggered by the poor performance of the conventional finance sector. The essence was to reach the overwhelming population of the poor to assist in the drive to alleviate poverty. Barely a million had been provided with some credit in Nigeria while a yawning 40 million poor people are yet to be attended to. In terms of supply, commercial and development finance institutions are in the fore front of the outfits that provide credits to the microfinance institutions. Despite their efforts, rates of interest, inequitable distribution of wealth and income and outreaching the poor constitute challenges to the operations. The establishment of microfinance institutions in Nigeria was based on weak institutional capacity, weak capital base, existence of a huge unserved market, utilization of SMEEIS fund among other thingsmicrofinance, financial institutions, agricultural credit and finance

    Studies on the morphology and compatibility between Schistosoma hæmatobium and the Bulinus sp. complex (gastropoda: planorbidae) in Cameroon

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    A description is given of the morphological variation of the shell, the radula features and the copulatory organ of Bulinus sp. (2n=36) from four populations in the western Cameroon crater lakes. To assess therole of diploid snails belonging to the Bulinus natalensis/tropicus complex in the transmission of urinary schistosomiasis in Cameroon, the relation between Bulinus sp. (from four Cameroon crater lakes) and Schistosoma haematobium (from three transmission foci) were studied. Bulinus sp. in thepresent study refers to the diploid snail (2n=36) tentatively identified as Bulinus natalensis or as Bulinus tropicus in the Cameroon crater lakes. The percentage infection of snails challenged ranged from 03.33 to 06.00% for Nchout Monoun population and from 01.85 to 04.76% for Monoun Ngouondam population. No progeny from Petponoun-East and Petponoun-West were experimentally successfully infected with S. haematobium. All the 351 snails dissected were euphallic. Previous malacological surveys revealed the absence of Bulinus sp. naturally infected with human schistosomes. These results suggested that Bulinus sp. was not susceptible to infection with S. haematobium in the Cameroon Western highland crater lakes. These observations justify the absence of transmission foci (for urinary schistosomiasis) in this area

    Influence of coating on the thermal resistance of a Ni-Based superalloy

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    In this paper, the influence of M-CrAlY polycrystalline coating on the thermal fatigue behavior of a Nickel-base superalloy has been investigated. A special device using a rotating bending machine and two thermal sources has been used to perform thermo-mechanical tests. The two thermal sources have been set to obtain temperature variations between 750 and 1120 °C in the central part of the specimens, with a frequency of 0.1 Hz. The results showed a deleterious effect of the coating on the fatigue resistance. Numerical simulations have been carried out on SAMCEF to determine the thermo-mechanical field of the so-tested specimens. Calculated thermo-mechanical cycles of critical sites are associated with microstructure evolution and damage by cracking observed on the specimens. Damage mechanisms related to the presence of coating are discussed

    Devonian Fungi: Interactions with the Green Alga Palaeonitella

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    This paper describes three new taxa of fossil aquatic fungi preserved in 400-million-year-old Lower Devonian Rhynie Chert. All of the fungal morphotypes are attached to cells of the green alga Palaeonitella cranii. Milleromyces rhyniensis is characterized by a holocarpic, epibiotic ^oosporangium with an elongate discharge tube that penetrates the host cell wall; arising from the base of the sporangium is an extensive rhizoidal system. Stages in infection by presumed zoospores are documented. In Lyonomyces pyriformis the globose-pyriform thallus is embedded in the surface coating of the cell wall. At the base of each thallus is a single rhizoid. Krispiromyces is extramatrical, holocarpic, and characterized by a short beak-like discharge papilla. The rhizoidal system appears to be apophysate. Some of these fungi were probably saprobes, while others were deemed parasitic because of the extensive hypertrophy of some of the algal cells. Although not all life history stages are represented, the discovery of these Lower Devonian forms greatly expands our knowledge of the biology and diversity of aquatic fungi in an ancient freshwater ecosystem

    Multi-pathogens sequence containing plasmids as positive controls for universal detection of potential agents of bioterrorism

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    BACKGROUND: The limited circulation of many of the agents that are likely to be used in a bioterrorism attack precludes the ready availability of positive controls. This means that only specialized laboratories can screen for the presence of these agents by nucleic amplification assays. Calibrated controls are also necessary for quantitative measurements. Primers and probes to be used in both conventional and real-time PCR assays were designed for the detection of agents likely to be used by a bioterrorist. Three plasmids, each of which contains 4 to 6 specific sequences from agents on the CDC Category A and B list (excluding RNA viruses) were constructed. Two plasmids incorporate the sequences of Category A and B agents, respectively. The third plasmid incorporates sequences from Variola major and organisms that cause rash-like illnesses that may be clinically confused with smallpox. An "exogenic sequence", introducing a NotI restriction site was incorporated in the native sequences of the bioterrorism agents inserted in plasmids. The designed molecular system for detection of bioterrorism agents was tested on each of these agents (except Monkeypox virus, Smallpox virus and 2 Burkholderia species for which no native DNA was available) and a collection of 50 isolates of C. burnetii using constructed plasmids as positive controls. RESULTS: Designed primers and probes allowed molecular detection, in either single or multiplex assays, of agent-specific targets with analytical sensitivities of between 1 and 100 DNA copies. The plasmids could be used as positive controls. False-positive results due to contamination by the positive control were easily detected by sequencing and eliminated by digestion with NotI. CONCLUSION: Plasmid A and B can be used as positive controls in molecular assays for the detection of bioterrorism agents in clinical specimens or environmental samples. Plasmid C can be used as a positive control in differentiation of vesicular rashes. It is also possible to avoid or to ensure immediate detection of false positive results due to contamination by positive controls using these plasmids. These plasmids and the corresponding primers and probes are immediately available for all clinical microbiology laboratories provided they have molecular amplification equipment

    Fossil arbuscular mycorrhizae from the Early Devonian

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    The 400 million-year-old Rhynie chert has provided a wealth of information not only of early land plants, but also of the fungi that inhabited this paleoecosystem. In this paper we report the first unequivocal evidence of arbuscules in an endomycorrhizal symbiosis. A new genus, Glomites, is characterized by extraradical, aseptate hyphae with a two-parted wall, and an intraradical, highly branched network of thin-walled hyphae. Hyphal branches produce terminal, elongate-globose multilayered spores that lack a basal septum. Other hyphae penetrate cell walls and form arbuscules. Arbuscules are morphologically identical to those of living arbuscular mycorrhizae (AM) in consisting of a basal trunk and highly dichotomous distal branches that form a bush-like tuft. Arbuscules are confined to a narrow band of specialized thinwalled cells in the outer cortex that continue to be meristematic. Features of the fossil biotroph are compared with those of extant arbuscular mycorrhizae. Although interpretations regarding the evolution of mycorrhizal mutualisms continue to be speculative, the demonstration of arbuscules in the Early Devonian indicates that nutrient transfer is an ancient phenomenon that may have been in existence when plants invaded the land
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