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1

A 7-deoxyloganetic acid glucosyltransferase contributes a key step in secologanin biosynthesis in Madagascar periwinkle.  

PubMed

Iridoids form a broad and versatile class of biologically active molecules found in thousands of plant species. In addition to the many hundreds of iridoids occurring in plants, some iridoids, such as secologanin, serve as key building blocks in the biosynthesis of thousands of monoterpene indole alkaloids (MIAs) and many quinoline alkaloids. This study describes the molecular cloning and functional characterization of three iridoid glucosyltransfeases (UDP-sugar glycosyltransferase6 [UGT6], UGT7, and UGT8) from Madagascar periwinkle (Catharanthus roseus) with remarkably different catalytic efficiencies. Biochemical analyses reveal that UGT8 possessed a high catalytic efficiency toward its exclusive iridoid substrate, 7-deoxyloganetic acid, making it better suited for the biosynthesis of iridoids in periwinkle than the other two iridoid glucosyltransfeases. The role of UGT8 in the fourth to last step in secologanin biosynthesis was confirmed by virus-induced gene silencing in periwinkle plants, which reduced expression of this gene and resulted in a large decline in secologanin and MIA accumulation within silenced plants. Localization studies of UGT8 using a carborundum abrasion method for RNA extraction show that its expression occurs preferentially within periwinkle leaves rather than in epidermal cells, and in situ hybridization studies confirm that UGT8 is preferentially expressed in internal phloem associated parenchyma cells of periwinkle species. PMID:24104568

Asada, Keisuke; Salim, Vonny; Masada-Atsumi, Sayaka; Edmunds, Elizabeth; Nagatoshi, Mai; Terasaka, Kazuyoshi; Mizukami, Hajime; De Luca, Vincenzo

2013-10-01

2

'Candidatus Phytoplasma malaysianum', a novel taxon associated with virescence and phyllody of Madagascar periwinkle (Catharanthus roseus).  

PubMed

This study addressed the taxonomic position and group classification of a phytoplasma responsible for virescence and phyllody symptoms in naturally diseased Madagascar periwinkle plants in western Malaysia. Unique regions in the 16S rRNA gene from the Malaysian periwinkle virescence (MaPV) phytoplasma distinguished the phytoplasma from all previously described 'Candidatus Phytoplasma' species. Pairwise sequence similarity scores, calculated through alignment of full-length 16S rRNA gene sequences, revealed that the MaPV phytoplasma 16S rRNA gene shared 96.5?% or less sequence similarity with that of previously described 'Ca. Phytoplasma' species, justifying the recognition of the MaPV phytoplasma as a reference strain of a novel taxon, 'Candidatus Phytoplasma malaysianum'. The 16S rRNA gene F2nR2 fragment from the MaPV phytoplasma exhibited a distinct restriction fragment length polymorphism (RFLP) profile and the pattern similarity coefficient values were lower than 0.85 with representative phytoplasmas classified in any of the 31 previously delineated 16Sr groups; therefore, the MaPV phytoplasma was designated a member of a new 16Sr group, 16SrXXXII. Phytoplasmas affiliated with this novel taxon and the new group included diverse strains infecting periwinkle, coconut palm and oil palm in Malaysia. Three phytoplasmas were characterized as representatives of three distinct subgroups, 16SrXXXII-A, 16SrXXXII-B and 16SrXXXII-C, respectively. PMID:22523165

Nejat, Naghmeh; Vadamalai, Ganesan; Davis, Robert E; Harrison, Nigel A; Sijam, Kamaruzaman; Dickinson, Matthew; Abdullah, Siti Nor Akmar; Zhao, Yan

2013-02-01

3

Complete nucleotide sequences of two begomoviruses infecting Madagascar periwinkle (Catharanthus roseus) from Pakistan.  

PubMed

Though Catharanthus roseus (Madagascar periwinkle) is an ornamental plant, it is famous for its medicinal value. Its alkaloids are known for anti-cancerous properties, and this plant is studied mainly for its alkaloids. Here, this plant has been studied for its viral diseases. Complete DNA sequences of two begomoviruses infecting C. roseus originating from Pakistan were determined. The sequence of one begomovirus (clone KN4) shows the highest level of nucleotide sequence identity (86.5 %) to an unpublished virus, chili leaf curl India virus (ChiLCIV), and then (84.4 % identity) to papaya leaf curl virus (PaLCV), and thus represents a new species, for which the name "Catharanthus yellow mosaic virus" (CYMV) is proposed. The sequence of another begomovirus (clone KN6) shows the highest level of sequence identity (95.9 % to 99 %) to a newly reported virus from India, papaya leaf crumple virus (PaLCrV). Sequence analysis shows that KN4 and KN6 are recombinants of Pedilanthus leaf curl virus (PedLCV) and croton yellow vein mosaic virus (CrYVMV). PMID:23065111

Ilyas, Muhammad; Nawaz, Kiran; Shafiq, Muhammad; Haider, Muhammad Saleem; Shahid, Ahmad Ali

2013-02-01

4

Vinca drug components accumulate exclusively in leaf exudates of Madagascar periwinkle  

PubMed Central

The monoterpenoid indole alkaloids (MIAs) of Madagascar periwinkle (Catharanthus roseus) continue to be the most important source of natural drugs in chemotherapy treatments for a range of human cancers. These anticancer drugs are derived from the coupling of catharanthine and vindoline to yield powerful dimeric MIAs that prevent cell division. However the precise mechanisms for their assembly within plants remain obscure. Here we report that the complex development-, environment-, organ-, and cell-specific controls involved in expression of MIA pathways are coupled to secretory mechanisms that keep catharanthine and vindoline separated from each other in living plants. Although the entire production of catharanthine and vindoline occurs in young developing leaves, catharanthine accumulates in leaf wax exudates of leaves, whereas vindoline is found within leaf cells. The spatial separation of these two MIAs provides a biological explanation for the low levels of dimeric anticancer drugs found in the plant that result in their high cost of commercial production. The ability of catharanthine to inhibit the growth of fungal zoospores at physiological concentrations found on the leaf surface of Catharanthus leaves, as well as its insect toxicity, provide an additional biological role for its secretion. We anticipate that this discovery will trigger a broad search for plants that secrete alkaloids, the biological mechanisms involved in their secretion to the plant surface, and the ecological roles played by them. PMID:20696903

Roepke, Jonathan; Salim, Vonny; Wu, Maggie; Thamm, Antje M. K.; Murata, Jun; Ploss, Kerstin; Boland, Wilhelm; De Luca, Vincenzo

2010-01-01

5

Colonization of Madagascar periwinkle (Catharanthus roseus), by endophytes encoding gfp marker.  

PubMed

This study reports the introduction of gfp marker in two endophytic bacterial strains (Pantoea agglomerans C33.1, isolated from cocoa, and Enterobacter cloacae PR2/7, isolated from citrus) to monitor the colonization in Madagascar perinwinkle (Catharanthus roseus). Stability of the plasmid encoding gfp was confirmed in vitro for at least 72 h of bacterial growth and after the colonization of tissues, under non-selective conditions. The colonization was observed using fluorescence microscopy and enumeration of culturable endophytes in inoculated perinwinkle plants that grew for 10 and 20 days. Gfp-expressing strains were re-isolated from the inner tissues of surface-sterilized roots and stems of inoculated plants, and the survival of the P. agglomerans C33:1gfp in plants 20 days after inoculation, even in the absence of selective pressure, suggests that is good colonizer. These results indicated that both gfp-tagged strains, especially P. agglomerans C33.1, may be useful tools to deliver enzymes or other proteins in plant. PMID:23695435

Torres, Adalgisa Ribeiro; Araújo, Welington Luiz; Cursino, Luciana; de Barros Rossetto, Priscilla; Mondin, Mateus; Hungria, Mariangela; Azevedo, João Lúcio

2013-07-01

6

Nuclear factors GT1 and 3AF1 interact with multiple sequences within the promoter of the Tdc gene from Madagascar periwinkle: GT1 is involved in UV light-induced expression  

Microsoft Academic Search

Plant secondary metabolites of the terpenoid indole alkaloid (TIA) class comprise several compounds with pharmaceutical applications.\\u000a A key step in the TIA biosynthetic pathway is catalysed by the enzyme tryptophan decarboxylase (TDC), which channels the primary\\u000a metabolite tryptophan into TIA metabolism. In Catharanthus roseus (Madagascar periwinkle), the Tdc gene is expressed throughout plant development. Moreover, Tdc gene expression is induced

P. B. F. Ouwerkerk; T. O. Trimborn; F. Hilliou; J. Memelink

1999-01-01

7

Characterization of the plastidial geraniol synthase from Madagascar periwinkle which initiates the monoterpenoid branch of the alkaloid pathway in internal phloem associated parenchyma.  

PubMed

Madagascar periwinkle (Catharanthus roseus [L.] G. Don, Apocynaceae) produces monoterpene indole alkaloids (MIAs), secondary metabolites of high interest due to their therapeutic value. A key step in the biosynthesis is the generation of geraniol from geranyl diphosphate (GPP) in the monoterpenoid branch of the MIA pathway. Here we report on the cloning and functional characterization of C. roseus geraniol synthase (CrGES). The full-length CrGES was over-expressed in Escherichia coli and the purified recombinant protein catalyzed the conversion of GPP into geraniol with a K(m) value of 58.5 ?M for GPP. In vivo CrGES activity was evaluated by heterologous expression in a Saccharomyces cerevisiae strain mutated in the farnesyl diphosphate synthase gene. Analysis of culture extracts by gas chromatography-mass spectrometry confirmed the excretion of geraniol into the growth medium. Transient transformation of C. roseus cells with a Yellow Fluorescent Protein-fusion construct revealed that CrGES is localized in plastid stroma and stromules. In aerial plant organs, RNA in situ hybridization showed specific labeling of CrGES transcripts in the internal phloem associated parenchyma as observed for other characterized genes involved in the early steps of MIA biosynthesis. Finally, when cultures of Catharanthus cells were treated with the alkaloid-inducing hormone methyl jasmonate, an increase in CrGES transcript levels was observed. This observation coupled with the tissue-specific expression and the subcellular compartmentalization support the idea that CrGES initiates the monoterpenoid branch of the MIA biosynthetic pathway. PMID:23102596

Simkin, Andrew J; Miettinen, Karel; Claudel, Patricia; Burlat, Vincent; Guirimand, Grégory; Courdavault, Vincent; Papon, Nicolas; Meyer, Sophie; Godet, Stéphanie; St-Pierre, Benoit; Giglioli-Guivarc'h, Nathalie; Fischer, Marc J C; Memelink, Johan; Clastre, Marc

2013-01-01

8

The Complete Plastid Genome Sequence of Madagascar Periwinkle Catharanthus roseus (L.) G. Don: Plastid Genome Evolution, Molecular Marker Identification, and Phylogenetic Implications in Asterids  

PubMed Central

The Madagascar periwinkle (Catharanthusroseus in the family Apocynaceae) is an important medicinal plant and is the source of several widely marketed chemotherapeutic drugs. It is also commonly grown for its ornamental values and, due to ease of infection and distinctiveness of symptoms, is often used as the host for studies on phytoplasmas, an important group of uncultivated plant pathogens. To gain insights into the characteristics of apocynaceous plastid genomes (plastomes), we used a reference-assisted approach to assemble the complete plastome of C. roseus, which could be applied to other C. roseus-related studies. The C. roseus plastome is the second completely sequenced plastome in the asterid order Gentianales. We performed comparative analyses with two other representative sequences in the same order, including the complete plastome of Coffeaarabica (from the basal Gentianales family Rubiaceae) and the nearly complete plastome of Asclepiassyriaca (Apocynaceae). The results demonstrated considerable variations in gene content and plastome organization within Apocynaceae, including the presence/absence of three essential genes (i.e., accD, clpP, and ycf1) and large size changes in non-coding regions (e.g., rps2-rpoC2 and IRb-ndhF). To find plastome markers of potential utility for Catharanthus breeding and phylogenetic analyses, we identified 41 C. roseus-specific simple sequence repeats. Furthermore, five intergenic regions with high divergence between C. roseus and three other euasterids I taxa were identified as candidate markers. To resolve the euasterids I interordinal relationships, 82 plastome genes were used for phylogenetic inference. With the addition of representatives from Apocynaceae and sampling of most other asterid orders, a sister relationship between Gentianales and Solanales is supported. PMID:23825699

Ku, Chuan; Chung, Wan-Chia; Chen, Ling-Ling; Kuo, Chih-Horng

2013-01-01

9

Ecological Modelling 185 (2005) 105131 Tropical deforestation in Madagascar: analysis using hierarchical,  

E-print Network

Ecological Modelling 185 (2005) 105­131 Tropical deforestation in Madagascar: analysis using­effect relationships for deforestation at various scales has proven difficult even when rates of deforestation appear approach to develop a novel deforestation model for the eastern wet forested zone of Madagascar, a global

Silander Jr., John A.

10

Does Diversity Matter In Modeling? Testing A New Version Of The FORMIX3 Growth Model For Madagascar Rainforests  

NASA Astrophysics Data System (ADS)

Ecological forecasting has become an essential tool used by ecologists to understand the dynamics of growth and disturbance response in threatened ecosystems such as the rainforests of Madagascar. In the species rich tropics, forest conservation is often eclipsed by anthropogenic factors, resulting in a heightened need for accurate assessment of biomass before these ecosystems disappear. The objective of this study was to test a new Madagascar rainforest specific version of the FORMIX3 growth model (Huth and Ditzer, 2000; Huth et al 1998) to assess how accurately biomass can be simulated in high biodiversity forests using a method of functional type aggregation in an individual-based model framework. Rainforest survey data collected over three growing seasons, including 265 tree species, was aggregated into 12 plant functional types based on size and light requirements. Findings indicated that the forest study site compared best when the simulated forest reached mature successional status. Multiple level comparisons between model simulation data and survey plot data found that though some features, such as the dominance of canopy emergent species and relative absence of small woody treelets are captured by the model, other forest attributes were not well reflected. Overall, the ability to accurately simulate the Madagascar rainforest was slightly diminished by the aggregation of tree species into size and light requirement functional type groupings.

Armstrong, A. H.; Fischer, R.; Shugart, H. H.; Huth, A.

2012-12-01

11

Climate change, predictive modeling and lemur health: Assessing impacts of changing climate on health and conservation in Madagascar  

E-print Network

Conservation Lemur Madagascar Parasite Species distribution modeling a b s t r a c t Deforestation for reintroduction efforts and addressing potential parasite risk in lemurs, humans and domestic animals. Ã? 2012 deforestation and a changing climate (Allnutt et al., 2008; Dufils, 2003; Elmqvist et al., 2007; Harper et al

Brown, Jason

12

A necessarily complex model to explain the biogeography of the amphibians and reptiles of Madagascar.  

PubMed

Pattern and process are inextricably linked in biogeographic analyses, though we can observe pattern, we must infer process. Inferences of process are often based on ad hoc comparisons using a single spatial predictor. Here, we present an alternative approach that uses mixed-spatial models to measure the predictive potential of combinations of hypotheses. Biodiversity patterns are estimated from 8,362 occurrence records from 745 species of Malagasy amphibians and reptiles. By incorporating 18 spatially explicit predictions of 12 major biogeographic hypotheses, we show that mixed models greatly improve our ability to explain the observed biodiversity patterns. We conclude that patterns are influenced by a combination of diversification processes rather than by a single predominant mechanism. A 'one-size-fits-all' model does not exist. By developing a novel method for examining and synthesizing spatial parameters such as species richness, endemism and community similarity, we demonstrate the potential of these analyses for understanding the diversification history of Madagascar's biota. PMID:25297804

Brown, Jason L; Cameron, Alison; Yoder, Anne D; Vences, Miguel

2014-01-01

13

Stone tools and foraging in northern Madagascar challenge Holocene extinction models  

PubMed Central

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar’s known occupational history, and thus the time during which people exploited Madagascar’s environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. 14C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton’i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050–1350, by 14C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. 14C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact. PMID:23858456

Dewar, Robert E.; Radimilahy, Chantal; Wright, Henry T.; Jacobs, Zenobia; Kelly, Gwendolyn O.; Berna, Francesco

2013-01-01

14

The subcellular localization of periwinkle farnesyl diphosphate synthase provides insight into the role of peroxisome in isoprenoid biosynthesis.  

PubMed

Farnesyl diphosphate (FPP) synthase (FPS: EC.2.5.1.1, EC.2.5.1.10) catalyzes the formation of FPP from isopentenyl diphosphate and dimethylallyl diphosphate via two successive condensation reactions. A cDNA designated CrFPS, encoding a protein showing high similarities with trans-type short FPS isoforms, was isolated from the Madagascar periwinkle (Catharanthus roseus). This cDNA was shown to functionally complement the lethal FPS deletion mutant in the yeast Saccharomyces cerevisiae. At the subcellular level, while short FPS isoforms are usually described as cytosolic proteins, we showed, using transient transformations of C. roseus cells with yellow fluorescent protein-fused constructs, that CrFPS is targeted to peroxisomes. This finding is discussed in relation to the subcellular distribution of FPS isoforms in plants and animals and opens new perspectives towards the understanding of isoprenoid biosynthesis. PMID:21872968

Thabet, Insaf; Guirimand, Grégory; Courdavault, Vincent; Papon, Nicolas; Godet, Stéphanie; Dutilleul, Christelle; Bouzid, Sadok; Giglioli-Guivarc'h, Nathalie; Clastre, Marc; Simkin, Andrew J

2011-11-15

15

Exploiting alkaloid biosynthesis in Madagascar periwinkle to obtain natural product derivatives and new biocatalysts .  

E-print Network

??Plant alkaloid biosynthesis produces many natural products with medicinal value. For example, vinblastine and vincristine from Catharanthus roseus monoterpene indole alkaloid biosynthesis, and camptothecin derivatives… (more)

Bernhardt, Peter, Ph. D. Massachusetts Institute of Technology

2010-01-01

16

Exploiting alkaloid biosynthesis in Madagascar periwinkle to obtain natural product derivatives and new biocatalysts  

E-print Network

Plant alkaloid biosynthesis produces many natural products with medicinal value. For example, vinblastine and vincristine from Catharanthus roseus monoterpene indole alkaloid biosynthesis, and camptothecin derivatives from ...

Bernhardt, Peter, Ph. D. Massachusetts Institute of Technology

2010-01-01

17

Madagascar Fauna Group  

NSDL National Science Digital Library

This is the homepage of the Madagascar Fauna Group, an "international consortium of zoos and related organizations that pool their talents and resources to work together in one of the world's most endangered places." Readers will find loads of information about the island and its diverse assortment of animal species, many of which are "bizarrely beautiful" and found nowhere else. The site also offers a number of Web links for general information about Madagascar, educational sites about lemurs and other animals, and links geared towards kids.

18

The Madagascar Hissing Cockroach: A New Model for Learning Insect Anatomy  

ERIC Educational Resources Information Center

Teaching and learning animal anatomy has a long history in the biology classroom. As in many fields of biology, decades of experience teaching anatomy have led to the unofficial selection of model species. However, in some cases the model may not be the best choice for our students. Our struggle to find an appropriate model for teaching and…

Heyborne, William H.; Fast, Maggie; Goodding, Daniel D.

2012-01-01

19

A small cohort of Island Southeast Asian women founded Madagascar  

PubMed Central

The settlement of Madagascar is one of the most unusual, and least understood, episodes in human prehistory. Madagascar was one of the last landmasses to be reached by people, and despite the island's location just off the east coast of Africa, evidence from genetics, language and culture all attests that it was settled jointly by Africans, and more surprisingly, Indonesians. Nevertheless, extremely little is known about the settlement process itself. Here, we report broad geographical screening of Malagasy and Indonesian genetic variation, from which we infer a statistically robust coalescent model of the island's initial settlement. Maximum-likelihood estimates favour a scenario in which Madagascar was settled approximately 1200 years ago by a very small group of women (approx. 30), most of Indonesian descent (approx. 93%). This highly restricted founding population raises the possibility that Madagascar was settled not as a large-scale planned colonization event from Indonesia, but rather through a small, perhaps even unintended, transoceanic crossing. PMID:22438500

Cox, Murray P.; Nelson, Michael G.; Tumonggor, Meryanne K.; Ricaut, François-X.; Sudoyo, Herawati

2012-01-01

20

Detection and identification of a new phytoplasma associated with periwinkle leaf yellowing disease in Taiwan  

Microsoft Academic Search

A new leaf yellowing disease was observed on periwinkle (Catharanthus roseus) in Taiwan in 2005. Sequence analysis of a 1.8 kb region of 16S rDNA, 16S-23S intergenic spacer region and partial 23S rDNA\\u000a revealed that the periwinkle leaf yellowing (PLY) disease was associated with a phytoplasma from the 16SrI group. In addition,\\u000a five cultivated plants including chrysanthemum (Chrysanthemum sp.), cosmos (Cosmos

Wuu-Yang Chen; Yao-Chen Huang; Meng-Lu Tsai; Chan-Pin Lin

21

Response of mycorrhizal periwinkle plants to aster yellows phytoplasma infection.  

PubMed

The objective of our research was to assess if arbuscular mycorrhizal (AM) fungal colonization can modify the effect of infection by two aster yellows phytoplasma strains (AY1, AYSim) in Catharanthus roseus plants. Both phytoplasma strains had a negative effect on the root fresh weight, but they differed in symptoms appearance and in their influence on photosynthetic and transpiration rates of the periwinkle plants. AM plants showed significantly reduced shoot fresh weight, while the transpiration rate was significantly increased. AM fungal colonization significantly affected shoot height and fresh weight of the plants infected by each phytoplasma strains as well as the root system of plants infected with the more aggressive AYSim phytoplasma strain. Double inoculation did not reduce the negative effects induced with phytoplasma alone on the photosynthetic activity of phytoplasma-infected plants. PMID:19756778

Kami?ska, Maria; Klamkowski, Krzysztof; Berniak, Hanna; Sowik, Iwona

2010-03-01

22

Ionic alkylleads in salt marsh periwinkles (Littorina irrorata)  

SciTech Connect

Salt marsh periwinkles (Littorina irrorata), from six sites in Maryland and Virginia, were examined to determine ionic alkyllead concentrations and possible alkyllead sources in lower Chesapeake Bay. Different sources of ethylleads and trimethyllead to this species were demonstrated by statistical comparisons of the concentrations of individual analytes from different sites. These comparisons also indicated (1) that environmentally mediated methylation of Pb/sup 2 +/ contributes appreciably to Me/sub 3/Pb/sup +/ concentrations in snails and (2) that the relative concentrations of individual analytes were consistent with an environmental methylation of ethyllead salts. Compared to females, males were characterized by significantly higher concentrations of several of the alkyllead analytes. In addition, an unknown lead-containing compound was present in all samples.

Krishnan, K.; Marshall, W.D.; Hatch, W.I.

1988-07-01

23

Oceanography of West Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Along selected hydrographical transects, a total of 182 CTD stations were conducted and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, along the west and south coast of Madagascar, the shelf is narrow and widen slightly along the north-west coast. In all ten transects the isotherms showed stratified waters from the coast to offshore. A maximum salinity layer was observed at subsurface in all transects. Dissolved oxygen had a maximum at around 500 m depth in all transects. Low fluorescence values were observed in the upper 150-200 m, with maximum values in the range of 0.14-0.22 µg/l at intermediate layers. The conditions were consistent along and between the transects, with more variation observed at transect 9. No upwelling was observed along the western coast. The surface temperature (5 m depth) increased from 22°C in the south to 26°C in the north. The horizontal distribution of surface salinities showed homogenous conditions with values between 35.4psu (south) and 35.0 psu (north). Also starting from the coast to offshore, both the surface temperatures and surface salinities showed homogenous patterns.

John, Bemiasa

2014-05-01

24

From herkogamy to cleistogamy--development of cleistogamy in periwinkle.  

PubMed

Periwinkle (Catharanthus roseus [L.] G. Don), an important medicinal plant, is an allogamous species in which the stigma is below the anthers. The receptive portion is at the base of the stigmatic head and thus automatic intra-flower self-pollination is excluded. The structure of the flower is of typical reverse herkogamy and pollination occurs through nectar-seeking insects. A few self-pollinating strains are also reported in which self-pollination is brought about by an increase in length of the style or of the ovary. Self-pollination is governed by allelic duplicate genes recessive to allogamy. An induced monogenic recessive mutant (EMS 17-1) with caducous closed corolla (corolla abscising before anthesis), isolated from variety, Dhawal, was crossed with two self-pollinating strains to study the possibility of obtaining cleistogamous recombinants combining closed corolla and self-pollination traits. Cleistogamous plants were obtained in which development of fruits and seeds occurred without opening of the corolla. Closed corolla and self-pollination were found to be independently inherited. A dominant gene in the parent in which self-pollination occurred due to an increase in length of the ovary, appeared to completely or partially inhibit expression of the gene for closed corolla in homozygous or heterozygous condition, respectively. The genetic basis of development of cleistogamy is described. Cleistogamy in periwinkle would facilitate in ensuring genetic purity, pollen containment, and seed production even in the absence of pollinators. This appears to be the first report on the development of cleistogamous plants in an allogamous species. PMID:23077233

Kulkarni, Raghavendra N; Baskaran, Kuppusamy

2013-01-01

25

The amino acid and stable isotope biogeochemistry of elephant bird (Aepyornis) eggshells from southern Madagascar  

Microsoft Academic Search

A diverse suite of animals became extinct on Madagascar during the Late Holocene. As observed on landmasses elsewhere, the extinction process broadly coincided with the arrival of people. Our research on the amino acid racemisation and the carbon and oxygen isotope biogeochemistry of elephant bird (Aepyornis) eggshells from southern Madagascar refines models that attempt to explain the extinction process. A

Simon J. Clarke; Gifford H. Miller; Marilyn L. Fogel; Allan R. Chivas; Colin V. Murray-Wallace

2006-01-01

26

The amino acid and stable isotope biogeochemistry of elephant bird ( Aepyornis) eggshells from southern Madagascar  

Microsoft Academic Search

A diverse suite of animals became extinct on Madagascar during the Late Holocene. As observed on landmasses elsewhere, the extinction process broadly coincided with the arrival of people. Our research on the amino acid racemisation and the carbon and oxygen isotope biogeochemistry of elephant bird (Aepyornis) eggshells from southern Madagascar refines models that attempt to explain the extinction process. A

Simon J. Clarke; Gifford H. Miller; Marilyn L. Fogel; Allan R. Chivas; Colin V. Murray-Wallace

2006-01-01

27

Investigating the Lithospheric Structure of Southern Madagascar  

NASA Astrophysics Data System (ADS)

The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly, although this interpretation has recently been questioned. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the eastern part of the study area, where there is some so-far poorly characterised seismicity. We present preliminary results on the lithospheric crust and mantle structure based on surface wave dispersion and waveform modelling, focussing on the contrast between the metamorphic areas in the east and the presumably stretched regions in the west. Interstation Green's functions have been obtained from all pairs of vertical broadband records, with coherent Rayleigh waves being identifiable for periods of 3-40 s. In addition, two-station phase dispersion measurements have allowed us to determine phase dispersion between 25 and 60 s. The ambient noise and earthquake data both indicate a slow-down of surface propagation in the western part of the array for periods < 40-45 s, but faster propagation in the western part for periods >45 s.

Tilmann, Frederik; Yuan, Xiaohui; Rümpker, Georg; Gerard, Rambolamana; Elisa, Rindraharisaona; Priestley, Keith

2014-05-01

28

Madagascar: Heads It's a Continent, Tails It's an Island  

NASA Astrophysics Data System (ADS)

Neither geologists nor biologists have a definition that is capable of classifying Madagascar unambiguously as an island or a continent; nor can they incorporate Malagasy natural history into a single model rooted in Africa or Asia. Madagascar is a microcosm of the larger continents, with a rock record that spans more than 3000 million years (Ma), during which it has been united episodically with, and divorced from, Asian and African connections. This is reflected in its Precambrian history of deep crustal tectonics and a Phanerozoic history of biodiversity that fluctuated between cosmopolitanism and parochialism. Both vicariance and dispersal events over the past 90 Ma have blended a unique endemism on Madagascar, now in decline following rapid extinctions that started about 2000 years ago.

de Wit, Maarten J.

29

Oceanography of East Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - September 2008) in Southern and Eastern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. A total of 102 CTD stations were conducted along selected hydrographical transects and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, the first section between latitude 25o-26oS showed sea surface temperature values ranging between 25oC to 15oC upper 250m depth. As part of the south-west, the shelf is narrow and widen slightly along the tip south of the Island coast. In contrast of the west coast, in all transects performed along the south and the east coast, in most cases, the isotherms showed non stratified waters from the coast to offshore. The presence of the upwelling system in the south-east coast modifies drastically the patterns of all measured parameters. Fluorescence had a maximum values (0.25 µg/l) at surface near the coast in 2nd to 5th transects. Inversely, low temperature values were observed along the south and south-east with minimum values in the range of 18. 5oC-11oC at 50-250 m depth. These conditions were consistent along and between the 2nd to 5th transects, with more variation observed at transect 5. The salinity values (5 m depth) decreased from 35.7 psu in the south to 34.5 psu in the east. The horizontal distribution of oxygen showed non homogenous conditions with values between 5 ml/l (south) and 2.5 ml/l (south-east). Also starting from the coast to offshore, surface temperatures and surface salinities, surface fluorescence and dissolved oxygen showed non homogenous patterns.

Bemiasa, John

2014-05-01

30

Micro-spatial distribution of two sibling periwinkle species across the intertidal indicates hybrdization.  

PubMed

Populations of periwinkles Littorina saxatilis (Olivi 1792) and L. arcana Hannaford Ellis, 1978 are well suited for microevolutionary studies, being at the same time closely related and intraspecifically diverse. The divergence between these two sibling species, sympatric over large parts of their distribution areas, is small, the only morphological difference being the pallial gland complex structure in females. Molecular identification is possible with the use of a RAPD nuclear marker (cloned A2.8 DNA fragment) typical for L. arcana. However, in some individuals from sympatric populations molecular and morphological criteria suggest conflicting species affiliation, which may be explained either by hybridization or by shared ancestral polymorphism. We tested the hybridization hypotheses examining the micro-spatial distribution of these two species across the intertidal zone in two distant sites at the Barents Sea. We found that (a) the frequency of putative hybrids in sympatric populations was proportional to the frequency of L. arcana; (b) L. saxatilis bearing A2.8 DNA fragment were almost absent in the lower part of the intertidal zone, where L. arcana was absent too; (c) there was a close positive correlation between the distribution of potential parent molluscs and putative hybrids. Moreover, logistic regression models showed a good agreement between the distribution of putative hybrid frequencies and that of parental species frequencies. All our observations taken together support the hypothesis of hybridization between L. saxatilis and L. arcana. Elucidating the mechanisms that support the species status of these sympatric populations is necessary. PMID:23887893

Granovitch, Andrei I; Maximovich, Alexei N; Avanesyan, Alina V; Starunova, Zinaida I; Mikhailova, Natalia A

2013-09-01

31

Discovery, characterization, and rational design of the enzymes involved in monoterpene indole alkaloid biosynthesis in Madagascar periwinkle  

E-print Network

The chemical diversity found in plants has served as a major source of inspiration to many synthetic and biological chemists. Nature has evolved enzyme active sites to catalyze the synthesis of structurally complex compounds ...

Giddings, Lesley-Ann

2011-01-01

32

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009  

E-print Network

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009 Influenza Centre, Institut Pasteur de Madagascar (IPM), Antananarivo, Madagascar, 2 Epidemiology Unit, IPM, Antananarivo, Madagascar Abstract Background: In Madagascar, despite an influenza surveillance established

Paris-Sud XI, Université de

33

Ecological and Economic Analysis of Watershed Protection in Eastern Madagascar  

Microsoft Academic Search

Watershed protection is one of the many goods and services provided by the world's fast disappearing tropical forests. Among the variety of watershed protection benefits, flood damage alleviation is crucial, particularly in upland watersheds. This study is a rare attempt to estimate flooding alleviation benefits, resulting from the protection of upland forests in Eastern Madagascar. A three stage model is

Randall A. Kramer; Daniel D. Richter; Subhrendu Pattanayak; Narendra P. Sharma

1997-01-01

34

Biochemical differences between trail mucus and adhesive mucus from marsh periwinkle snails.  

PubMed

The composition of the adhesive form of marsh periwinkle mucus was compared to the trail mucus used during locomotion. The trail mucus consists primarily of large, carbohydrate-rich molecules with some relatively small proteins. In contrast, the adhesive mucus has 2.7 times as much protein with no significant difference in carbohydrate concentration. The resulting gel has roughly equal amounts of protein and carbohydrate. This substantial increase in protein content is due to the additional presence of two proteins with molecular weights of 41 and 36 kD. These two proteins are absent from the trail mucus. Both proteins are glycosylated, have similar amino acid compositions, and have isoelectric points of 4.75. This change in composition corresponds to an order of magnitude increase in tenacity with little clear change in overall concentration. The difference between adhesive and non-adhesive mucus suggests that relatively small proteins are important for controlling the mechanics of periwinkle mucus. PMID:12480724

Smith, Andrew M; Morin, Martha C

2002-12-01

35

NEW FINDINGS AT ANDRAHOMANA CAVE, SOUTHEASTERN MADAGASCAR  

Microsoft Academic Search

A remote eolianite cave and sinkhole complex on the southeast coast of Madagascar has played a major role in the history of paleontology in Madagascar. Andrahomana Cave has yielded a rich fossil record of the extinct megafauna. Expeditions in 2000 and 2003 produced a wealth of new material and provided the first systematic information concerning the genesis, stratigraphy, and taphonomy

D. A. BURNEY; N. V ASEY; L. R. GODFREY; W. L. JUNGERS

2008-01-01

36

Removal of Remazol Brilliant Violet5R dye using periwinkle shells  

Microsoft Academic Search

The purpose of this research is to obtain optimal processing conditions for the adsorption of Remazol Brilliant Violet-5R (RBV-5R) dye onto activated carbon prepared from periwinkle shells (PSAC) by chemical activation with KOH using response surface methodology. Central composite design (CCD) was used to determine the effects of three preparation variables; CO2 activation temperature, CO2 activation time and KOH:char impregnation

Olugbenga Solomon Bello; Mohd Azmier Ahmad

2011-01-01

37

Exploring the Association Between People and Deforestation in Madagascar  

Microsoft Academic Search

\\u000a An island widely recognized for remarkably high biological diversity, Madagascar continues to experience considerable deforestation.\\u000a This study explores possible causes of forest loss between 1990 and 2000. Applying a multivariate probit model, the study\\u000a considers a range of human geographic, physical geographic, and infrastructure data to identify likely reasons for deforestation\\u000a during the final decade of the twentieth century. Results

L. J. Gorenflo; Catherine Corson; Kenneth M. Chomitz; Grady Harper; Miroslav Honzák; Berk Özler

38

DIET OF THE MADAGASCAR HARRIER-HAWK, POLYBORO1DES RADIATUS, IN SOUTHEASTERN MADAGASCAR  

Microsoft Academic Search

We recorded prey deliveries, pellets and food remains of the Madagascar Harrier-Hawk (Polyboroides radiatus) from 10 August-5 December 1997 at Berenty and Bealoka private reserves in extreme southeastern Madagascar. The Madagascar Harrier-Hawk had a variable diet, eating at least 16 prey species, including reptiles (2.4% of biomass), birds (11.5%), mammals (85.9%) and insects (0.2%). The largest component of the diet

STEVEN M. GOODMAN

39

Eating the dead in Madagascar.  

PubMed

Cannibalism has been poorly understood and has seldom been studied, since it was often suppressed by missionaries and colonial administrators, and very few societies still practise it. Cannibalistic practices are more complex than was originally thought. They may be supported in societies under stress or in times of famine, to reflect aggression and antisocial behaviour (in cases where the bodies of enemies killed in battle or people who have harmed the family are eaten), or to honour a dead kinsman. It was, for example, noted in Madagascar during the imperial campaigns of Ranavalona I in the period 1829 - 1853. Two types of cannibalism have been described: exocannibalism, where enemies were consumed, and endocannibalism, where dead relatives were eaten to assist their passing to the world of the ancestors, or to prolong contact with beloved and admired family members and absorb their good qualities. This article reviews some of the beliefs and motivations that surrounded the cannibalistic practices of the people of Madagascar in the 19th century.  PMID:24300654

Campbell, Gwyn

2013-12-01

40

Informe sobre actividades 2005 Baobabs, Madagascar  

E-print Network

Instituto produjo algunos resultados notables, como el descubrimiento de un reservorio de virus Ebola enInforme sobre actividades 2005 #12;Índice Baobabs, Madagascar #12;1 Introducción El IRD en el mundo

41

Phylogeography and Molecular Epidemiology of Yersinia pestis in Madagascar  

E-print Network

Phylogeography and Molecular Epidemiology of Yersinia pestis in Madagascar Amy J. Vogler1 , Fabien Epidemiology of Yersinia pestis in Madagascar. PLoS Negl Trop Dis 5(9): e1319. doi:10.1371/journal.pntd.0001319. pestis in Madagascar has been difficult to study due to the great genetic similarity among isolates. We

Boyer, Edmond

42

What Makes (the) Antankarana, Antankarana? Reckoning Group Identity in Northern Madagascar  

Microsoft Academic Search

This paper discusses different ways of reckoning group identity in the Ankarana region of northern Madagascar. It focuses on two distinct but related models that people employ in construing the meaning of the term 'Antankarana' and identifying the boundaries of the collective it denotes. The first, inclusive, model suggests that any person who respects the moral and political orders of

Andrew Walsh

2001-01-01

43

Urban household food security, Madagascar.  

PubMed

This article discusses the success of the Madagascar Food Security and Nutrition project in decreasing malnutrition and monitoring child health. Success has occurred in the following realms: effective collaboration between government and nongovernmental organizations (NGOs), capacity building through investment in training of community workers, increased quality of services provided by community nutrition workers, community involvement, government commitment, and a flexible program design. NGOs were able to respond to community concerns by adding program inputs without losing the focus on core nutrition interventions. Community workers were selected from a group of mothers. Women were trained to monitor the growth of all children under age 5. Children who were severely malnourished were identified and referred to rehabilitation centers for treatment lasting up to 3 weeks. The program offered support and nutrition education for mothers of sick children. One drawback of the treatment program was the inability of mothers to stay for long periods of time during the duration of treatment. The program offers distribution of iodine capsules as part of a long-term salt iodization program that is supported by UNICEF and the World Bank. The program also offers microcredit. Since 1993, 28,000 children under age 5 have been weighed each month. These children came from two provinces and belonged to 300,000 families. The monitored children were 66% of the total number of children aged under 5 years. Malnutrition rates decreased from 46% to 37%. PMID:12293185

Balachander, J

1997-12-01

44

Evolution in the hypervariable environment of Madagascar  

PubMed Central

We show that the diverse ecoregions of Madagascar share one distinctive climatic feature: unpredictable intra- or interannual precipitation compared with other regions with comparable rainfall. Climatic unpredictability is associated with unpredictable patterns of fruiting and flowering. It is argued that these features have shaped the evolution of distinctive characteristics in the mammalian fauna of the island. Endemic Herpestidae and Tenrecidae and members of five endemic primate families differ from closely related species elsewhere, exhibiting extremes of “fastness” and “slowness” in their life histories. Climatic features may also account for the dearth of frugivorous birds and mammals in Madagascar, and for the evolutionary prevalence of species with large body mass. PMID:17698810

Dewar, Robert E.; Richard, Alison F.

2007-01-01

45

Palatability and chemical defense of Phragmites australis to the marsh periwinkle snail Littoraria irrorata.  

PubMed

Coastal marsh habitats are impacted by many disturbances, including habitat destruction, pollution, and the introduction of invasive species. The common reed, Phragmites australis, has been particularly invasive in the mesohaline regions of the Chesapeake Bay, but few studies have investigated its role in trophic interactions with North American marsh consumers. The marsh periwinkle snail Littoraria irrorata is a common grazer in marshes and grazes on the native grass Spartina alterniflora. Whether this snail grazes on Phragmites has not been addressed. We found Spartina leaves to be tougher than those of Phragmites, but despite this, snails consumed significantly more Spartina than Phragmites. Subsequent experiments demonstrated that Phragmites is chemically deterrent to snails by an unknown, moderately polar, compound. Further studies are required to more fully understand the interactions between Phragmites, herbivores, and Spartina, and how they may impact marsh ecosystems. PMID:21691807

Hendricks, Lindsey G; Mossop, Hannah E; Kicklighter, Cynthia E

2011-08-01

46

Geological evolution of the Neoproterozoic Bemarivo Belt, northern Madagascar  

USGS Publications Warehouse

The broadly east-west trending, Late Neoproterozoic Bemarivo Belt in northern Madagascar has been re-surveyed at 1:100 000 scale as part of a large multi-disciplinary World Bank-sponsored project. The work included acquisition of 14 U-Pb zircon dates and whole-rock major and trace element geochemical data of representative rocks. The belt has previously been modelled as a juvenile Neoproterozoic arc and our findings broadly support that model. The integrated datasets indicate that the Bemarivo Belt is separated by a major ductile shear zone into northern and southern "terranes", each with different lithostratigraphy and ages. However, both formed as Neoproterozoic arc/marginal basin assemblages that were translated southwards over the north-south trending domains of "cratonic" Madagascar, during the main collisional phase of the East African Orogeny at ca. 540 Ma. The older, southern terrane consists of a sequence of high-grade paragneisses (Sahantaha Group), which were derived from a Palaeoproterozoic source and formed a marginal sequence to the Archaean cratons to the south. These rocks are intruded by an extensive suite of arc-generated metamorphosed plutonic rocks, known as the Antsirabe Nord Suite. Four samples from this suite yielded U-Pb SHRIMP ages at ca. 750 Ma. The northern terrane consists of three groups of metamorphosed supracrustal rocks, including a possible Archaean sequence (Betsiaka Group: maximum depositional age approximately 2477 Ma) and two volcano-sedimentary sequences (high-grade Milanoa Group: maximum depositional age approximately 750 Ma; low grade Daraina Group: extrusive age = 720-740 Ma). These supracrustal rocks are intruded by another suite of arc-generated metamorphosed plutonic rocks, known as the Manambato Suite, 4 samples of which gave U-Pb SHRIMP ages between 705 and 718 Ma. Whole-rock geochemical data confirm the calc-alkaline, arc-related nature of the plutonic rocks. The volcanic rocks of the Daraina and Milanoa groups also show characteristics of arc-related magmatism, but include both calc-alkaline and tholeiitic compositions. It is not certain when the two Bemarivo terranes were juxtaposed, but ages from metamorphic rims on zircon suggest that both the northern and southern terranes were accreted to the northern cratonic margin of Madagascar at about 540-530 Ma. Terrane accretion included the assembly of the Archaean Antongil and Antananarivo cratons and the high-grade Neoproterozoic Anaboriana Belt. Late- to post-tectonic granitoids of the Maevarano Suite, the youngest plutons of which gave ca. 520 Ma ages, intrude all terranes in northern Madagascar showing that terrane accretion was completed by this time. ?? 2009 Natural Environment Research Council (NERC).

Thomas, R. J.; De Waele, B.; Schofield, D. I.; Goodenough, K. M.; Horstwood, M.; Tucker, R.; Bauer, W.; Annells, R.; Howard, K.; Walsh, G.; Rabarimanana, M.; Rafahatelo, J. M.; Ralison, A. V.; Randriamananjara, T.

2009-01-01

47

New Primates Discovered in Madagascar and Brazil  

NSDL National Science Digital Library

Nine lemur and two marmoset species native to the forests of Madagascar and Brazil, and new to (Western) science, were described earlier this month. Despite the excitement associated with this discovery, the forest habitats of most of these species appear to be already at risk from development pressures. This news brief from Environment News Service gives an overview of the discovery.

Lazaroff, Cat

2001-01-01

48

Welfare dynamics in rural Kenya and Madagascar  

Microsoft Academic Search

This paper presents comparative qualitative and quantitative evidence from rural Kenya and Madagascar in an attempt to untangle the causality behind persistent poverty. We find striking differences in welfare dynamics depending on whether one uses total income, including stochastic terms and inevitable measurement error, or the predictable, structural component of income based on a household's asset holdings. Our results suggest

Christopher B. Barrett; Paswel Phiri Marenya; John Mcpeak; Bart Minten; Festus Murithi; Willis Oluoch-Kosura; Jean Claude Randrianarisoa; Jhon Rasambainarivo; Justine Wangila

2006-01-01

49

Congruence between allozyme and RAPD data in assessing macrogeographical genetic variation in the periwinkle Littorina striata (Mollusca, Gastropoda)  

Microsoft Academic Search

The population genetic structure of the Macaronesian planktonic-developing periwinkle Littorina striata was analysed, using random amplified polymorphic DNA analysis (RAPD). Two primers, yielding six polymorphic loci, were surveyed to infer the population genetic structure of five geographically separated populations (i.e. 10–2000 km). Biased and unbiased allele frequency and heterozygosity levels were estimated and were found to be highly similar. As

H de Wolf; T Backeljau; R Verhagen

1998-01-01

50

HSP90 homologue from Madagascar periwinkle (Catharanthus roseus): cDNA sequence, regulation of protein expression and location in the endoplasmic reticulum  

Microsoft Academic Search

We describe cDNAs for a HSP90 homologue from Catharanthus roseus and studies on the regulation of expression. The largest cDNA (2670 bp) coded for a protein of 817 amino acids with a calculated size of 93 491 Da and a pI of 4.61. It contained a eucaryotic secretory signal, the endoplasmic reticulum (ER) targeting and retention signal (Lys-Asp-Glu-Leu), and the

Gudrun Schröder; Markus Beck; Johannes Eichel; Hans-Peter Vetter; Joachim Schröder

1993-01-01

51

Growth inhibitory activity of fatty acid methyl esters in the whole seed oil of madagascar periwinkle (Apocyanaceae) against Helicoverpa armigera (Lepidoptera: Noctuidae).  

PubMed

Crude hexane and water extracts of Catharanthus roseus Linn. (Syn: Vinca rosea) (Apocyanaceae) stem, leaf, and seed exhibited pesticidal activity against Helicoverpa armigera (Hübner) (Lepidoptera Noctuidae). The extracts differed significantly in their efficacy, with the crude hexane extract of whole seed being the most effective in curtailing pupal survivorship to 18% followed by the hexane extracts of leaf (21%) and stem (24%). Average pupal weight (68.2 mg) and length (1.5 cm) in the whole seed treatment were drastically reduced, compared with the controls (415.2 mg and 2.72 cm), subsequently reducing adult emergence to 15.7%. SiO2 column purification yielded eight fractions of which fraction 1 exhibited 90% larval mortality, with severe reduction of the larvae weight (12.7 mg) and length (1.5 cm). Gas chromatographic-mass spectrometric analysis of fraction 1 suggested the presence of 16 compounds, among which oleic, linoleic, palmitic, and margaric acids were detected as major constituents. Presence of the alkane hydrocarbons triacontane, tetracosane, and heptacosane also was noted. PMID:19610438

Satyan, R S; Malarvannan, S; Eganathan, P; Rajalakshmi, S; Parida, Ajay

2009-06-01

52

Imperfect Isolation: Factors and Filters Shaping Madagascar's Extant Vertebrate Fauna  

PubMed Central

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar’s colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island’s biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island’s paleogeographical evolution to determine how particular events influenced the arrival of the island’s extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar’s tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island’s isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar’s extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar’s unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more recently arriving clades. Thus, the composition of Madagascar’s endemic vertebrate assemblage itself provides evidence of the island's paleogeographic history. PMID:23626770

Samonds, Karen E.; Godfrey, Laurie R.; Ali, Jason R.; Goodman, Steven M.; Vences, Miguel; Sutherland, Michael R.; Irwin, Mitchell T.; Krause, David W.

2013-01-01

53

A giant frog with South American affinities from the Late Cretaceous of Madagascar  

PubMed Central

Madagascar has a diverse but mainly endemic frog fauna, the biogeographic history of which has generated intense debate, fueled by recent molecular phylogenetic analyses and the near absence of a fossil record. Here, we describe a recently discovered Late Cretaceous anuran that differs strikingly in size and morphology from extant Malagasy taxa and is unrelated either to them or to the predicted occupants of the Madagascar–Seychelles–India landmass when it separated from Africa 160 million years ago (Mya). Instead, the previously undescribed anuran is attributed to the Ceratophryinae, a clade previously considered endemic to South America. The discovery offers a rare glimpse of the anuran assemblage that occupied Madagascar before the Tertiary radiation of mantellids and microhylids that now dominate the anuran fauna. In addition, the presence of a ceratophryine provides support for a controversial paleobiogeographical model that posits physical and biotic links among Madagascar, the Indian subcontinent, and South America that persisted well into the Late Cretaceous. It also suggests that the initial radiation of hyloid anurans began earlier than proposed by some recent estimates. PMID:18287076

Evans, Susan E.; Jones, Marc E. H.; Krause, David W.

2008-01-01

54

A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar  

PubMed Central

Background Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of, and in some cases challenging, aspects of this general model. Results Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea hunter-gatherers, the neighbouring Vezo fishermen, and the Merina central highlanders (n = 266). Complete mitochondrial DNA genome sequences reveal several unresolved lineages, and a new, deep branch of the out-of-Africa founder clade M has been identified. This new haplogroup, M23, has a limited global distribution, and is restricted to Madagascar and a limited range of African and Southwest Asian groups. Conclusions The geographic distribution, phylogenetic placement and molecular age of M23 suggest that the colonization of Madagascar was more complex than previously thought. PMID:20003445

2009-01-01

55

Rosewood of Madagascar: Between democracy and conservation  

Microsoft Academic Search

In 2009 an estimated 52,000 tonnes of precious wood from ca. 100,000 rosewood and ebony trees was logged in north - east Madagascar, one third originating from Marojejy National Park and its environs, the remainder from in and around Masoala National Park. At least 500,000 additional trees and many miles of vines were cut to make rafts to transport the

Hery Randriamalala; Zhou Liu

2010-01-01

56

Agro-Environmental Determinants of Avian Influenza Circulation: A Multisite Study in Thailand, Vietnam and Madagascar  

PubMed Central

Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004–2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced. PMID:25029441

Paul, Mathilde C.; Gilbert, Marius; Desvaux, Stephanie; Rasamoelina Andriamanivo, Harena; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Veronique

2014-01-01

57

Digestive enzymes of the saltmarsh periwinkleLittorina irrorata (Mollusca: Gastropoda).  

PubMed

The saltmarsh periwinkleLittorina irrorata is well adapted for the digestion of a wide range of polysaccharides. Enzyme extracts attacked cellulose, pectin, xylan, bean gum and mannan (common in cell walls of higher plants), as well as starch and laminarin (representative of major polysaccharide classes in fungal, algal, and animal tissues). Activities were generally highes at a ph of 5 or 6. There was no evidence that chitin was digested, but 19 other enzymes, active toward various carbohydrates, lipids and peptides, were demonstrated. Enzymatic activity toward Azocoll, a general substrate for proteinase activity, was weak compared to that of other aquatic detritivores. The maximum was reached at a pH of 8. Enzymatic activities were generally measured with extracts of the entire visceral hump. Separate stomach or intestine extracts also gave strong activities. The stomach was the most acidic section of the digestive system with an average pH of 5.8; the intestine had an average pH of 7.3. PMID:23494343

Bärlocher, F; Arsuffi, T L; Newell, S Y

1989-03-01

58

An Abelisauroid Theropod Dinosaur from the Turonian of Madagascar  

PubMed Central

Geophysical evidence strongly supports the complete isolation of India and Madagascar (Indo-Madagascar) by ?100 million years ago, though sparse terrestrial fossil records from these regions prior to ?70 million years ago have limited insights into their biogeographic history during the Cretaceous. A new theropod dinosaur, Dahalokely tokana, from Turonian-aged (?90 million years old) strata of northernmost Madagascar is represented by a partial axial column. Autapomorphies include a prominently convex prezygoepipophyseal lamina on cervical vertebrae and a divided infraprezygapophyseal fossa through the mid-dorsal region, among others. Phylogenetic analysis definitively recovers the species as an abelisauroid theropod and weakly as a noasaurid. Dahalokely is the only known dinosaur from the interval during which Indo-Madagascar likely existed as a distinct landmass, but more complete material is needed to evaluate whether or not it is more closely related to later abelisauroids of Indo-Madagascar or those known elsewhere in Gondwana. PMID:23637961

Farke, Andrew A.; Sertich, Joseph J. W.

2013-01-01

59

Blood parasites in birds from Madagascar.  

PubMed

Madagascar has long been recognized for its unique and diverse biota. In particular, significant effort has been made to establish baseline population data to better conserve the endemic avifauna. During field expeditions between 1993 and 2004, birds were mist-netted at 11 different sites, at elevations from 60 m to 2,050 m above sea level. Data on endemic status, forest type, and habitat preference were recorded. Thin blood films from 947 birds, belonging to 26 families and 64 species, were examined by light microscopy to determine the prevalence of blood parasites. Of these 947 birds, 30.7% were infected by at least one species of blood parasite, 26.8% of which were infected by more than one species. Species of Haemoproteus were the most prevalent (17.4%), followed by microfilariae (11.0%), Leucocytozoon spp. (9.4%), Plasmodium spp. (1.9%), Trypanosoma spp. (0.9%), and Babesia spp. (0.2%). Species level identifications confirmed the presence of 47 species of hemosporidians and trypanosomes, which is notably high and mirrors the diversity of their avian hosts. Eleven (23.4%) of these parasite species were new to science and thought to be endemic to the island. Significant differences in prevalence were observed by sample site, forest type (humid vs. dry), and habitat preference. Birds from all elevational zones sampled were infected, although not all parasite genera were present in each zone. Four of the six endemic avian families or subfamilies (Bernieridae, Brachypteraciidae, Philepittinae [Eurylaimidae], and Vangidae) were sampled and found to be parasitized. Of the families with the largest sample sizes, the Zosteropidae and Ploceidae had the highest prevalence of infection (65.6% and 49.3%, respectively). The vectors of hematozoan parasites in Madagascar are currently unknown. These results add to the current knowledge of avian parasitism in Madagascar and are of particular interest for the conservation of endemic species, as well as threatened or endangered populations. PMID:19901367

Savage, Amy F; Robert, Vincent; Goodman, Steven M; Raharimanga, Vahomalala; Raherilalao, Marie Jeanne; Andrianarimisa, Aristide; Ariey, Frédéric; Greiner, Ellis C

2009-10-01

60

Temporal and spatial evolution of dynamic support from river profiles: A framework for Madagascar  

NASA Astrophysics Data System (ADS)

We present a strategy for calculating uplift rates as a function of space and time from large sets of longitudinal river profiles. This strategy assumes that the shape of a river profile is controlled by the history of uplift rate and moderated by the erosional process. We assume that upstream drainage area is invariant. The algorithm was tested on a set of ˜100 river profiles which were extracted from a digital elevation model of Madagascar. This set of profiles was simultaneously inverted to obtain uplift rate as a smooth function of space and time. The fit between observed and calculated profiles is excellent and suggests that Madagascar was uplifted by 1-2 km at rates of 0.2-0.4 mm/yr during the last ˜15 Myrs. The location of Madagascar suggests that its topographic elevation is maintained by convective circulation of the sub-lithospheric mantle. Residual depth anomalies of oceanic fragments encompassing the island show that the island straddles a dynamic topographic gradient which generates asymmetric Neogene uplift. Volcanism, warped peneplains and uplifted marine terraces corroborate the existence of youthful uplift. We suggest that sets of longitudinal river profiles contain useful information about the history of regional uplift which can be extracted by inverse modeling and calibrated by independent geologic observations.

Roberts, Gareth G.; Paul, Jonathan D.; White, Nicky; Winterbourne, Jeffrey

2012-04-01

61

The amino acid and stable isotope biogeochemistry of elephant bird ( Aepyornis) eggshells from southern Madagascar  

NASA Astrophysics Data System (ADS)

A diverse suite of animals became extinct on Madagascar during the Late Holocene. As observed on landmasses elsewhere, the extinction process broadly coincided with the arrival of people. Our research on the amino acid racemisation and the carbon and oxygen isotope biogeochemistry of elephant bird ( Aepyornis) eggshells from southern Madagascar refines models that attempt to explain the extinction process. A correlation between the extent of isoleucine epimerisation (aIle/Ile) and radiocarbon age of eggshells allows aIle/Ile to serve as a proxy for eggshell age. The aIle/Ile values indicate the majority (87%) of eggshells in this study are Holocene, with the remainder representing Pleistocene Aepyornis populations, and that further amino acid analyses would help to constrain the timing of Aepyornis extinction. Carbon isotope ratios in the organic and calcite fractions of eggshells indicate that Aepyornis primarily browsed C 3 vegetation. Oxygen isotope values are more negative and less variable than in eggshells of ostriches living in semi-arid environments, suggesting that Aepyornis populations relied upon groundwater-fed coastal wetlands for their drinking water. The isotope results require that the changing abundances of C 3 vegetation and groundwater-fed watering points be considered in models that aim to understand the extinction of Aepyornis in southern Madagascar.

Clarke, Simon J.; Miller, Gifford H.; Fogel, Marilyn L.; Chivas, Allan R.; Murray-Wallace, Colin V.

2006-09-01

62

Origin of birefringence in andradite from Arizona, Madagascar, and Iran  

NASA Astrophysics Data System (ADS)

The crystal structure of four birefringent andradite samples (two from Arizona, one from Madagascar, and one from Iran) was refined with the Rietveld method, space group Iaoverline{3} d, and monochromatic synchrotron high-resolution powder X-ray diffraction (HRPXRD) data. Each sample contains an assemblage of three different cubic phases. From the electron-microprobe (EMPA) results, fine-scale intergrowths in the Arizona-2 and Madagascar samples appear homogeneous with nearly identical compositions of {Ca2.99Mg0.01}?3[{{Fe}}_{1.99}^{3 + } {{Mn}}_{0.01}^{3 + }]?2(Si2.95Al0.03 {{Fe}}_{0.02}^{3 + })?3O12, Adr98 (Arizona-2), and Adr97 (Madagascar). Both samples are near-end-member andradite, ideally {Ca3}[{{Fe}}2^{3 + }](Si3)O12, so cation ordering in the X, Y, or Z sites is not possible. Because of the large-scale intergrowths, the Arizona-1 and Iran samples contain three different compositions. Arizona-1 has compositions Adr97 (phase-1), Adr93Grs4 (phase-2), and Adr87Grs11 (phase-3). Iran sample has compositions Adr86Uv12 (phase-1), Adr69Uv30 (phase-2), and Adr76Uv22 (phase-3). The crystal structure of the three phases within each sample was modeled quite well as indicated by the Rietveld refinement statistics of reduced ?2 and overall R ( F 2) values of, respectively, 1.980 and 0.0291 (Arizona-1); 1.091 and 0.0305 (Arizona-2); 1.362 and 0.0231 (Madagascar); and 1.681 and 0.0304 (Iran). The dominant phase for each sample has the following unit-cell parameters (Å) and weight fractions (%): a = 12.06314(1), 51.93(9) (Arizona-1); 12.04889(1), 52.47(1) (Arizona-2); 12.06276(1), 52.21(8) (Madagascar); and 12.05962(2), 63.3(1) (Iran). For these dominant phases, the distances and site occupancy factors ( sofs) in terms of neutral atoms at the Ca(X), Fe(Y), and Si(Z) sites are as follows: = 2.4348, Fe-O = 2.0121(6), Si-O = 1.6508(6) Å; Ca( sof) = 0.955(2), Fe( sof) = 0.930(2), and Si( sof) = 0.917(2) (Arizona-1); = 2.4288, Fe-O = 2.0148(7), Si-O = 1.6476(7) Å; Ca( sof) = 0.953(2), Fe( sof) = 0.891(2), and Si( sof) = 0.927(2) (Arizona-2); = 2.4319, Fe-O = 2.0220(6), Si-O = 1.6460(6) Å; Ca( sof) = 0.955(2), Fe( sof) = 0.941(2), and Si( sof) = 0.939(2) (Madagascar); and = 2.4344, Fe-O = 2.0156(8), Si-O = 1.6468(8) Å; Ca( sof) = 0.928(2), Fe( sof) = 0.908(2), and Si( sof) = 0.932(3) (Iran). The sofs based on the EMPA results are similar to those obtained from the Rietveld refinement. Each phase in the HRPXRD results can be correlated with a specific chemical composition. For example, the Iran sample composition Adr63Uv30 corresponds to phase-3 that has the smallest unit-cell parameter; Adr76Uv22 corresponds to phase-1 that has the intermediate cell value; and Adr86Uv13 corresponds to phase-2 that has the largest unit-cell parameter. The bond distances compare well with those obtained from radii sum. The three different cubic phases in each sample cause strain that arises from the mismatch of the cubic unit-cell parameters and give rise to birefringence.

Antao, Sytle M.; Klincker, Allison M.

2013-07-01

63

Impact of Women’s Harvest Practices on Pandanus guillaumetii in Madagascar’s Lowland Rainforests 1  

Microsoft Academic Search

\\u000a Impact of Women’s Harvest Practices on\\u000a Pandanus guillaumetii\\u000a in Madagascar’s Lowland Rainforests.\\u000a Pandanus guillaumetii B.C. Stone is endemic to the east coast rainforests of Madagascar. The plant is an important non-timber forest product (NTFP)\\u000a for the local population living near these forests, and its leaves are collected by women to be woven into mats. These mats\\u000a have economic value and

Giacomo Fedele; Zora Lea Urech; Maik Rehnus; Jean-Pierre Sorg

2011-01-01

64

BREEDING BIOLOGY AND FOOD HABITS OF THE MADAGASCAR KESTREL (FALCO NEWTONI) IN NORTHEASTERN MADAGASCAR  

Microsoft Academic Search

We studied Madagascar Kestrels (Falco newtoni) on Masoala Peninsula, northeastern Mada- gascar during the 1997 and 1998 breeding seasons. We located five nest sites and observed eight nesting attempts during the two breeding seasons. All nests were in tree cavities and averaged 13.8 + 2.0 m (SE) above the ground in trees averaging 22.8 +- 0.8 m (SE) in height

LILY-ARISON RENE DE ROLAND; JEANNENEY RABEARIVONY; GILBERT RAZAFIMANJATO; RUSSELL THORSTROM

65

[Plants regeneration from genetically transformed root and callus cultures of periwinkle Vinca minor L. and foxglove purple Digitalis purpurea L].  

PubMed

Plants regenerated from hairy roots and calluses of foxglove purple and periwinkle have been obtained. It was found that organogenesis in hairy root culture occurs spontaneously on hormone-free medium but with different efficiencies. The frequency of direct shoot formation from root cultures was up to 60% in Digitalis and 3.7% in Vinca. Addition of 1 mg/l BA, 0.1 mg/l NAA and 5% sucrose to B5 medium increased regenerative capacity of Vinca roots up to 19.1%. Regenerated plants showed morphological features typically seen in Ri-transgenic plants. They include growth and plagiotropism of the root system, increased shoot formation, changed leaf morphology and short internodes. PMID:25318175

Leshina, L G; Bulko, O V

2014-01-01

66

Imperfect isolation: factors and filters shaping Madagascar's extant vertebrate fauna.  

PubMed

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar's colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island's biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island's paleogeographical evolution to determine how particular events influenced the arrival of the island's extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar's tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island's isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar's extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar's unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more recently arriving clades. Thus, the composition of Madagascar's endemic vertebrate assemblage itself provides evidence of the island's paleogeographic history. PMID:23626770

Samonds, Karen E; Godfrey, Laurie R; Ali, Jason R; Goodman, Steven M; Vences, Miguel; Sutherland, Michael R; Irwin, Mitchell T; Krause, David W

2013-01-01

67

First record of gars (Lepisosteidae, Actinopterygii) on Madagascar: Late Cretaceous remains from the Mahajanga Basin  

Microsoft Academic Search

Gars (Lepisosteidae, Actinopterygii) are reported from Madagascar for the first time, from exposures of the Upper Cretaceous (?Campanian) Maevarano Formation in the Mahajanga Basin, northwestern Madagascar. The material includes relatively common isolated scales, and vertebral centra, teeth, fin rays, and dermal cranial elements, all assigned to Lepisosteus sp. This new record from Madagascar adds to previously documented Cretaceous Gondwanan gar

Michael D. Gottfried; David W. Krause

1998-01-01

68

Immune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci Persistence?  

E-print Network

of the foci. In this study, we aimed to investigate serological responses to plague in wild black rats fromImmune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci, Antananarivo, Madagascar Abstract Background: Plague is endemic within the central highlands of Madagascar

Paris-Sud XI, Université de

69

The Spread of Influenza A(H1N1)pdm09 Virus in Madagascar Described by a Sentinel Surveillance  

E-print Network

The Spread of Influenza A(H1N1)pdm09 Virus in Madagascar Described by a Sentinel Surveillance Virology Unit, National Influenza Center, Institut Pasteur de Madagascar, Antananarivo, Madagascar, 3 Malagasy Ministry of Health, Antananarivo, Madagascar Abstract Background: The influenza A(H1N1)pdm09 virus

Paris-Sud XI, Université de

70

Evaluating ring-tailed lemurs (Lemur catta) from southwestern Madagascar for a genetic population bottleneck.  

PubMed

In light of historical and recent anthropogenic influences on Malagasy primate populations, in this study ring-tailed lemur (Lemur catta) samples from two sites in southwestern Madagascar, Beza Mahafaly Special Reserve (BMSR) and Tsimanampetsotsa National Park (TNP), were evaluated for the genetic signature of a population bottleneck. A total of 45 individuals (20 from BMSR and 25 from TNP) were genotyped at seven microsatellite loci. Three methods were used to evaluate these populations for evidence of a historical bottleneck: M-ratio, mode-shift, and heterozygosity excess tests. Three mutation models were used for heterozygosity excess tests: the stepwise mutation model (SMM), two-phase model (TPM), and infinite allele model (IAM). M-ratio estimations indicated a potential bottleneck in both populations under some conditions. Although mode-shift tests did not strongly indicate a population bottleneck in the recent historical past when samples from all individuals were included, a female-only analysis indicated a potential bottleneck in TNP. Heterozygosity excess was indicated under two of the three mutation models (IAM and TPM), with TNP showing stronger evidence of heterozygosity excess than BMSR. Taken together, these results suggest that a bottleneck may have occurred among L. catta in southwestern Madagascar in the recent past. Given knowledge of how current major stochastic climatic events and human-induced change can negatively impact extant lemur populations, it is reasonable that comparable events in the historical past could have caused a population bottleneck. This evaluation additionally functions to highlight the continuing environmental and anthropogenic challenges faced by lemurs in southwestern Madagascar. PMID:22052208

Parga, Joyce A; Sauther, Michelle L; Cuozzo, Frank P; Jacky, Ibrahim Antho Youssouf; Lawler, Richard R

2012-01-01

71

Predator-induced alarm responses in the common periwinkle, Littorina littorea: dependence on season, light conditions, and chemical labelling of predators  

Microsoft Academic Search

Chemically mediated alarm reactions of the common periwinkle, Littorina littorea (L.), were studied in laboratory experiments during two consecutive summers, and one intermediate autumn season. Responses\\u000a to chemical stimuli were detected as crawl-out responses, i.e. movements of snails out of the water. Snails were exposed to\\u000a extracts of injured conspecifics, extracts of the mussel Modiolus modiolus (L.), and water conditioned

H. P. Jacobsen; O. B. Stabell

1999-01-01

72

Molecular characterization of a cytokinin-inducible periwinkle protein showing sequence homology with pathogenesis-related proteins and the Bet v 1 allergen family  

Microsoft Academic Search

Cytokinin treatment of periwinkle callus cultures increased the accumulation of a protein, designated T1, in two-dimensional separated protein extracts. The first 30 NH2-terminal amino acids were determined by Edman degradation and showed significant sequence homology with intracellular pathogenesis-related (IPR) plant proteins and the Bet v 1 allergen family. The deduced amino acid sequence of cDNAs coding for T1, isolated by

Sabine Carpin; Sylvia Laffer; Françoise Schoentgen; Rudolf Valenta; Jean-Claude Chénieux; Marc Rideau; Saïd Hamdi

1998-01-01

73

Malagasy dialects and the peopling of Madagascar  

PubMed Central

The origin of Malagasy DNA is half African and half Indonesian, nevertheless the Malagasy language, spoken by the entire population, belongs to the Austronesian family. The language most closely related to Malagasy is Maanyan (Greater Barito East group of the Austronesian family), but related languages are also in Sulawesi, Malaysia and Sumatra. For this reason, and because Maanyan is spoken by a population which lives along the Barito river in Kalimantan and which does not possess the necessary skill for long maritime navigation, the ethnic composition of the Indonesian colonizers is still unclear. There is a general consensus that Indonesian sailors reached Madagascar by a maritime trek, but the time, the path and the landing area of the first colonization are all disputed. In this research, we try to answer these problems together with other ones, such as the historical configuration of Malagasy dialects, by types of analysis related to lexicostatistics and glottochronology that draw upon the automated method recently proposed by the authors. The data were collected by the first author at the beginning of 2010 with the invaluable help of Joselinà Soafara Néré and consist of Swadesh lists of 200 items for 23 dialects covering all areas of the island. PMID:21632612

Serva, Maurizio; Petroni, Filippo; Volchenkov, Dima; Wichmann, S?ren

2012-01-01

74

Understanding the persistence of plague foci in Madagascar.  

PubMed

Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar. PMID:24244760

Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

2013-11-01

75

Holocene Indian Ocean Cosmic Impacts: The Megatsunami Chevron Evidence From Madagascar  

NASA Astrophysics Data System (ADS)

The 2.6 million year Quaternary period terrestrial physical record lacks definitive crater evidence for major regional catastrophic impacts by asteroids and comets other than the 10.5-km diameter Botsumtwi structure in Ghana and the 14.0-km diameter Zhamanshin structure in Kazakhstan [1] dating between about 900 and 1100 kya. Current cosmic impact rate models suggest that an average of between 3-6 globally catastrophic impacts should have occurred on the Earth during the Quaternary, along with several additional significant regional impacts in addition to Zhamanshin and Botsumtwi. These models and data indicate that the great majority of the "missing" major impact locations would likely have occurred in poorly studied oceanic settings. Only recently have Late Quaternary and Holocene period coastal paleo-megatsunami chevron deposits been defined in the Caribbean and along the western coasts of Australia, along with the suggestion that some may have been created by oceanic cosmic impacts in distinction to those caused by landslips, eruptions, and seismic events. We investigate the possibility that many or most megatsunami chevrons occurring along the southern coast of Madagascar were caused by two or more major Holocene Indian Ocean cosmic impacts. This hypothesis is based on an initial study of the worldwide archaeological and anthropological record, and the preliminary study of satellite images of the chevrons, selected Indian Ocean deep-sea cores, sea-floor bathymetry, and physical examination of the Madagascar deposits themselves. Candidate Indian Ocean impact structures are identified and correlated with the southern Madagascar megatsunami chevron deposits. [1] Masse, W.B. 2007 The Archaeology and Anthropology of Quaternary Period Cosmic Impact. In Bobrowsky, P.T. & Rickman, H. (eds.)Comets/Asteroid Impacts and Human Society. Springer, Berlin (in press).

Masse, W.; Bryant, E.; Gusiakov, V.; Abbott, D.; Rambolamana, G.; Raza, H.; Courty, M.; Breger, D.; Gerard-Little, P.; Burckle, L.

2006-12-01

76

A chronology for late prehistoric Madagascar.  

PubMed

A database has been assembled with 278 age determinations for Madagascar. Materials 14C dated include pretreated sediments and plant macrofossils from cores and excavations throughout the island, and bones, teeth, or eggshells of most of the extinct megafaunal taxa, including the giant lemurs, hippopotami, and ratites. Additional measurements come from uranium-series dates on speleothems and thermoluminescence dating of pottery. Changes documented include late Pleistocene climatic events and, in the late Holocene, the apparently human-caused transformation of the environment. Multiple lines of evidence point to the earliest human presence at ca. 2300 14C yr BP (350 cal yr BC). A decline in megafauna, inferred from a drastic decrease in spores of the coprophilous fungus Sporormiella spp. in sediments at 1720+/-40 14C yr BP (230-410 cal yr AD), is followed by large increases in charcoal particles in sediment cores, beginning in the SW part of the island, and spreading to other coasts and the interior over the next millennium. The record of human occupation is initially sparse, but shows large human populations throughout the island by the beginning of the Second Millennium AD. Dating of the "subfossil" megafauna, including pygmy hippos, elephant birds, giant tortoises, and large lemurs, demonstrates that most if not all the extinct taxa were still present on the island when humans arrived. Many taxa overlapped chronologically with humans for a millennium or more. The extinct lemurs Hadropithecus stenognathus, Pachylemur insignis, Mesopropithecus pithecoides, and Daubentonia robusta, and the elephant birds Aepyornis spp. and Mullerornis spp., were still present near the end of the First Millennium AD. Palaeopropithecus ingens, Megaladapis edwardsi, and Archaeolemur sp. (cf. edwardsi) may have survived until the middle of the Second Millennium A.D. One specimen of Hippopotamus of unknown provenance dates to the period of European colonization. PMID:15288523

Burney, David A; Burney, Lida Pigott; Godfrey, Laurie R; Jungers, William L; Goodman, Steven M; Wright, Henry T; Jull, A J Timothy

2004-01-01

77

Confiage et scolarisation des enfants en milieu rural à Madagascar  

Microsoft Academic Search

(english) Much empirical research found that fostered children are less likely than others to attend school, which suggests that fostering may be disadvantaged human capital investment. This paper tries to analyze the impact of child fostering on school enrollment in rural Madagascar. We examine firstly if schooling is a principal reason of household’s decision to foster a child. Indeed, biological

Nelly Rakoto-Tiana

2012-01-01

78

Late Holocene environments at Lake Mitsinjo, northwestern Madagascar  

Microsoft Academic Search

Two sediment cores from Lake Mitsinjo in northwestern Madagascar were analysed for evidence of past environmental changes. The unconformities in a 503 cm core from the centre of the lake and a 306 cm core from the shore were correlated to identify a hiatus in sedimentation that occurred just before ca. 1000 BP. The 3500-year stratigraphic record was analysed for

Katsumi Matsumotot; David A. Burneyt

1994-01-01

79

An old adaptive radiation of forest dung beetles in Madagascar  

Microsoft Academic Search

Adaptive radiations of mammals have contributed to the exceptionally high levels of biodiversity and endemism in Madagascar. Here we examine the evolutionary history of the endemic dung beetle tribe Helictopleurini (Scarabaeidae) and its relationship to the widely distributed Oniticellini and Onthophagini. Helictopleurini species are dependent on mammals for their resources. We date the single origin of the tribe at 37

Helena Wirta; Luisa Orsini; Ilkka Hanski

2008-01-01

80

Healing words: becoming a spirit-host in Madagascar  

Microsoft Academic Search

In discussion of healing processes in sub-Saharan Africa, emphasis is characteristically placed on the role of performance. Yet in spirit mediumship, speech is also an important element in therapeutic practices. In Madagascar, the spirits (tromba) are often of exotic origins (frequently in time as well as space) and the language used is likewise exotic. A complex of techniques of enchantment is

John Mack

2011-01-01

81

Revision of the Megaloptera (Insecta: Neuropterida) of Madagascar.  

PubMed

The Megaloptera fauna of Madagascar comprise two endemic genera: Haplosialis Navás, 1927 (Sialidae) and Madachauliodes Paulian, 1951 (Corydalidae: Chauliodinae). Here the two genera are revised, with detailed descriptions and illustrations. A new species, Madachauliodes bicuspidatus Liu, Price & Hayashi, sp. nov., is described. Furthermore the phylogeny and biogeography of the Madagascan fauna is discussed. PMID:24870678

Liu, Xingyue; Price, Benjamin W; Hayashi, Fumio; De Moor, Ferdinand; Yang, Ding

2014-01-01

82

Autochthonous Melioidosis in Humans, Madagascar, 2012 and 2013  

PubMed Central

Melioidosis is an often fatal infectious disease affecting humans and animals in the tropics. Only sporadic cases have been reported from Africa and the Indian Ocean region. We describe 2 confirmed autochthonous cases of human melioidosis in Madagascar, both from novel genotypes of Burkholderia pseudomallei.

Djaomazala, Innocente; Dubois-Cauwelaert, Natasha; Raharimanga, Vaomalala; Ralison, Fidiarivony; Herindrainy, Perlinot; Andriamalala, Nivosoa C.; Sarovich, Derek S.; Mayo, Mark; Kaestli, Mirjam; Currie, Bart J.

2014-01-01

83

Family Background, School Characteristics, and Children's Cognitive Achievement in Madagascar  

ERIC Educational Resources Information Center

This paper uses linked household, school, and test score data from Madagascar to investigate the relation of household characteristics and school factors to the cognitive skills of children ages 8-10 and 14-16. In contrast to most achievement test studies in developing countries, the study uses representative rather than school-based samples of…

Glick, Peter; Randrianarisoa, Jean Claude; Sahn, David E.

2011-01-01

84

Evidence of early butchery of giant lemurs in Madagascar.  

PubMed

We report here definitive evidence of butchery, most probably associated with hunting, of giant extinct lemurs by early human settlers in Madagascar. Specimens of Palaeopropithecus ingens and Pachylemur insignis from two sites in southwestern Madagascar, Taolambiby and Tsirave, show classic signs of butchering. We compared these to the bones (also from Taolambiby) of butchered Propithecus verreauxi, a lemur still living in the region. The characteristics of the tool-induced extinct-lemur bone alterations (sharp cuts and chop marks near joints, oblique cuts along the shafts, spiral fractures, and percussion striae) suggest skinning, disarticulation, and filleting. Conclusive evidence of megafaunal modification by humans in Madagascar was limited previously to a few hippo and elephant bird bones and one extinct aye-aye tooth. New evidence comes not from archaeological sites, but from specimens collected in the early 1900s, without stratigraphic records, at "subfossil" sites (i.e., sites renowned for their late Pleistocene or Holocene fossils, often lacking human artifacts). Whereas these are hardly the most ideal samples for analysis of this kind, careful scrutiny of the characteristics of the cut marks has allowed us to document butchery beyond any reasonable doubt. One bone with definitive cut marks has been dated to the very earliest part of the human period in Madagascar. Continued, careful research on the bones in subfossil collections is warranted. PMID:16225904

Perez, Ventura R; Godfrey, Laurie R; Nowak-Kemp, Malgosia; Burney, David A; Ratsimbazafy, Jonah; Vasey, Natalia

2005-12-01

85

The freshwater crabs of Madagascar (Crustacea, Decapoda, Potamoidea)  

Microsoft Academic Search

The taxonomy of the freshwater crabs of Madagascar is revised and the num­ ber of genera raised from five to six. Two new genera are erected and one genus is synonymised. Hydrothelphusa is revised with four species: H. agilis A. Milne-Edwards , 1872, H. madagascarien sis (A. Milne-Edwards, 1872), H. bombetokensis (Rathbun, 1904) and H. goudoti (H. Milne Edwards, 1853)

Neil CUMBERLIDGE; Richard V. STERNBERG

86

Lemur Habitat and Dental Senescence in Ranomafana National Park, Madagascar  

E-print Network

- ferent kinds of foods may exhibit different rates of dental attrition because their teeth are less wellLemur Habitat and Dental Senescence in Ranomafana National Park, Madagascar Stephen J. King,1, we compare the rates of dental wear in sifaka groups living in nearby habitats that differ

Boyer, Doug M.

87

A bizarre predatory dinosaur from the Late Cretaceous of Madagascar  

Microsoft Academic Search

Here we report the discovery of a small-bodied (~1.8 m) predatory dinosaur from the Late Cretaceous (Maastrichtian) of Madagascar. Masiakasaurus knopfleri, gen. et sp. nov., represented by several skull elements and much of the postcranial skeleton, is unique in being the only known theropod with a highly procumbent and distinctly heterodont lower dentition. Such a derived dental morphology is otherwise

Scott D. Sampson; Matthew T. Carrano; Catherine A. Forster

2001-01-01

88

Tackling computer generated clouds in 'Madagascar: The Crate Escape'  

Microsoft Academic Search

Computer generated clouds are an important component in the animated movie 'Madagascar: The Crate Escape'. Our particle based cloud system is used throughout the animated feature in collaboration with our Layout, Lighting and Matte painting departments. It was clear from the beginning that several objectives had to be defined - the techniques used had to be relatively fast and able

Laurent Kermel; Fangwei Lee; Joon Taik Song; Scott Peterson

2008-01-01

89

When Origins Matter: The Politics of Commemoration in Northern Madagascar  

Microsoft Academic Search

This article discusses different understandings of the origins of a ritual associated with the Antankaraña polity of northern Madagascar. If we are to under- stand how history is ''made'' differently at different points in time, we must consider the interrelatedness of historical narratives and the sociopolitical contexts in which they are produced and interpreted. By focusing on one purportedly commemorative

Andrew Walsh

2001-01-01

90

[On the road to hope with street children in Madagascar].  

PubMed

On a four-month humanitarian mission to Madagascar, two young child care nurses were able to use their nursing skills, listening skills and their imagination to help orphaned children. They were able to discover the island's social and cultural reality. Here they look back at this experience of deep poverty which also included moments of sharing and hope. PMID:22919804

Legrand, Solenne; Pichon, Caroline

2012-01-01

91

Antimicrobial resistance of bacterial enteropathogens isolated from stools in Madagascar  

PubMed Central

Background Diarrheal diseases are a major public health problem in developing countries, and are one of the main causes of hospital admissions in Madagascar. The Pasteur Institute of Madagascar undertook a study to determine the prevalence and the pathogenicity of bacterial, viral and protozoal enteropathogens in diarrheal and non-diarrheal stools of children aged less than 5 years in Madagascar. We present here the results of the analysis of antimicrobial susceptibility of the bacteria isolated during this study. Methods The study was conducted in the community setting in 14 districts of Madagascar from October 2008 to May 2009. Conventional methods and PCR were used to identify the bacteria; antimicrobial susceptibility was determined using an agar diffusion method for enterobacteriaceae and MICs were measured by an agar dilution method for Campylobacter sp. In addition to the strains isolated during this study, Salmonella sp and Shigella sp isolated at the Pasteur Institute of Madagascar from 2005 to 2009 were included in the analysis to increase the power of the study. Results Twenty-nine strains of Salmonella sp, 35 strains of Shigella sp, 195 strains of diarrheagenic E. coli, 203 strains of C. jejuni and 71 strains of C. coli isolated in the community setting were tested for antibiotic resistance. Fifty-five strains of Salmonella sp and 129 strains of Shigella sp isolated from patients referred to the Pasteur Institute of Madagascar were also included in the study. Many E. coli and Shigella isolates (around 80%) but fewer Salmonella isolates were resistant to ampicillin and trimethoprim/sulfamethoxazole. A small proportion of strains of each species were resistant to ciprofloxacin and only 3% of E. coli strains presented a resistance to third generation cephalosporins due to the production of extended-spectrum beta-lactamases. The resistance of Campylobacter sp to ampicillin was the most prevalent, whereas less than 5% of isolates were resistant to each of the other antibiotics. Conclusion The highest prevalence of antimicrobial resistance was to ampicillin and trimethoprim/sulfamethoxazole. Antibiotic treatment is not recommended for children with diarrhea in Madagascar and the emphasis should be placed on oral rehydration. PMID:24568189

2014-01-01

92

Blindness and Cataract Surgical Services in Atsinanana Region, Madagascar  

PubMed Central

Purpose: To assess the prevalence and causes of avoidable blindness in Atsinanana Region, Madagascar, with the Rapid Assessment of Avoidable Blindness (RAAB) survey. We analyzed the hospital records to supplement the findings for public health care planning. Materials and Methods: Only villages within a two-hour walk from a road, about half of the population of Atsinanana was included. Seventy-two villages were selected by population-proportional-to-size sampling. In each village, compact segment sampling was used to select 50 people over age 50 for eye examination using standard RAAB methods. Records at the two hospitals providing cataract surgery in the region were analyzed for information on patients who underwent cataract surgery in 2010. Cataract incidence rate and target cataract surgery rate (CSR) was modeled from age-specific prevalence of cataract. Results: The participation rate was 87% and the sample prevalence of blindness was 1.96%. Cataract was responsible for 64% and 85.7% of blindness and severe visual impairment, respectively. Visual impairment was due to cataract (69.4%) and refractive error (14.1%). There was a strong positive correlation between cataract surgical rate by district and the proportion of people living within 2 hours of a road. There were marked differences in the profiles of the cataract patients at the two facilities. The estimated incidence of cataract at the 6/18 level was 2.4 eyes per 100 people over age 50 per year. Conclusions: Although the survey included only people with reasonable access, the main cause of visual impairment was still cataract. The incidence of cataract is such that it ought to be possible to eliminate it as a cause of visual impairment, but changes in service delivery at hospitals and strategies to improve access will be necessary for this change. PMID:24791107

Randrianaivo, Jean-Baptiste; Anholt, R. Michele; Tendrisoa, Diarimirindra Lazaharivony; Margiano, Nestor Jean; Courtright, Paul; Lewallen, Susan

2014-01-01

93

Natural resources and rural livelihoods: Differences between migrants and non-migrants in Madagascar  

PubMed Central

BACKGROUND Although natural resources play a central role in rural livelihoods across the globe, little research has explored the relationship between migration and natural capital use, particularly in combination with other livelihood capitals (i.e., human, social, financial and physical). OBJECTIVE Grounded in the rural livelihood framework, this paper explores the association between the livelihood capital availability, especially natural capital, for migrants and non-migrants in rural Madagascar. METHODS Data from the 2008/2009 Demographic and Health Survey are used in combination with satellite imagery of vegetation coverage (Normalized Difference Vegetation Index, NDVI) to proxy natural resources. Hierarchical multilevel models allow for inclusion of cross-level interactions between migrant status and proximate natural resources as determinants of the status of livelihood assets. RESULTS Three key findings emerge. First, higher levels of proximate natural resources are associated with greater financial, human, and social capital for both migrants and non-migrants. Second, migrants have, on average, greater financial, physical, human, and social capital than non-migrants, and urban-to-rural migrants do exceptionally well on all capital asset categories. Third, migrants residing in areas with higher levels of natural capital tend to have significantly higher levels of human capital (education). CONCLUSION Although we cannot examine livelihood strategies per se, the results suggest variation in livelihood potential among migrants and non-migrants in rural Madagascar, with migrants tending to have greater capital assets. In addition, access to natural resources is a central livelihood strategy.

Nawrotzki, Raphael J.; Hunter, Lori M.; Dickinson, Thomas W.

2013-01-01

94

Possible Fruit Protein Effects on Primate Communities in Madagascar and the Neotropics  

PubMed Central

Background The ecological factors contributing to the evolution of tropical vertebrate communities are still poorly understood. Primate communities of the tropical Americas have fewer folivorous but more frugivorous genera than tropical regions of the Old World and especially many more frugivorous genera than Madagascar. Reasons for this phenomenon are largely unexplored. We developed the hypothesis that Neotropical fruits have higher protein concentrations than fruits from Madagascar and that the higher representation of frugivorous genera in the Neotropics is linked to high protein concentrations in fruits. Low fruit protein concentrations in Madagascar would restrict the evolution of frugivores in Malagasy communities. Methodology/Principal Findings We reviewed the literature for nitrogen concentrations in fruits from the Neotropics and from Madagascar, and analyzed fruits from an additional six sites in the Neotropics and six sites in Madagascar. Fruits from the Neotropical sites contain significantly more nitrogen than fruits from the Madagascar sites. Nitrogen concentrations in New World fruits are above the concentrations to satisfy nitrogen requirements of primates, while they are at the lower end or below the concentrations to cover primate protein needs in Madagascar. Conclusions/Significance Fruits at most sites in the Neotropics contain enough protein to satisfy the protein needs of primates. Thus, selection pressure to develop new adaptations for foods that are difficult to digest (such as leaves) may have been lower in the Neotropics than in Madagascar. The low nitrogen concentrations in fruits from Madagascar may contribute to the almost complete absence of frugivorous primate species on this island. PMID:20016841

Ganzhorn, Jorg U.; Arrigo-Nelson, Summer; Boinski, Sue; Bollen, An; Carrai, Valentina; Derby, Abigail; Donati, Giuseppe; Koenig, Andreas; Kowalewski, Martin; Lahann, Petra; Norscia, Ivan; Polowinsky, Sandra Y.; Schwitzer, Christoph; Stevenson, Pablo R.; Talebi, Mauricio G.; Tan, Chia; Vogel, Erin R.; Wright, Patricia C.

2009-01-01

95

A multidisciplinary study on lavaka (gully erosion) formation in Central Highlands, Madagascar  

NASA Astrophysics Data System (ADS)

Madagascar is a very important place to study erosion. Due to some forms of gully erosion called lavaka the country is among the first regarding its erosion rate. Lavakas are very abundant in the highlands of Madagascar (they can reach up to 30/km2). Therefore they have been subject of many studies in the past 60 years. Lavaka formation seems to be triggered by many regional effects (thin laterite layer on thick saprolite layer, smoothly convex hills, climate) and local causes (rain attack, earth falls, lack of vegetation) both natural and anthropogenic (deforestation, roads, paths) but the real nature of these erosion features are not fully understood. Based on field surveys, photogrammetrical, geomorphological and lithological-sedimentological methods two different kinds of lavaka (toe-slope and mid-slope) were studied in Tsiafahy, Central Highlands. Our main goal was to understand the formation of lavakas in order to prevent their consequences such as the degradation of agricultural lands, villages and nearby roads. For this purpose we digitalized geological and hydrological maps of the country and compared them with maps showing the occurrence of lavakas in Madagascar. 3D (three-dimensional) modeling of the actual eroding surface was achieved with photogrammetric methods applying the few hundred photos we made during the field surveys. We tested several 3D modeling software and used the best ones (with higher accuracy and resolution) to model a toe-slope lavaka. In order to model a more complex mid-slope lavaka a new program has been developed in MATLAB as well. Such photogrammetric evaluation and 3D modeling of lavakas were achieved for the first time and therefore the results are yet preliminary. Sedimentological features (grain size distribution and mineral composition) of an active mid-slope lavaka were also investigated to define the difference between the lateritic and saprolitic layers of the lavaka. Preliminary results show that the most important causes of lavaka formation are the climate and the lithological features of these areas. According to our field surveys and analysis lavaka's saprolitic layer can be divided into two different units: a yellow colored saprolitic layer with smaller hydraulic conductivity and a reddish saprolitic layer which could be interpreted as the transition between the yellow saprolitic and the upper red lateritic layer. Field surveys and photos show that the complex structure of the lavakas strongly correlate to the distribution of these different saprolitic units. The understanding of 3D distribution of these material types is the key to the lavaka formation. Further studies will concentrate on improving the obtained models and using them for geomorphologic studies including calculating relief, aspects and volume.

Raveloson, A.; Visnovitz, F.; Székely, B.; Molnár, G.; Udvardi, B.

2012-04-01

96

A bizarre predatory dinosaur from the Late Cretaceous of Madagascar.  

PubMed

Here we report the discovery of a small-bodied (approximately 1.8 m) predatory dinosaur from the Late Cretaceous (Maastrichtian) of Madagascar. Masiakasaurus knopfleri, gen. et sp. nov., represented by several skull elements and much of the postcranial skeleton, is unique in being the only known theropod with a highly procumbent and distinctly heterodont lower dentition. Such a derived dental morphology is otherwise unknown among dinosaurs. Numerous skeletal characteristics indicate that Masiakasaurus is a member of Abelisauroidea, an enigmatic clade of Gondwanan theropods. Previously, small-bodied abelisauroids were known only from Argentina. The occurrence of Masiakasaurus on Madagascar suggests that small-bodied abelisauroids, like their larger-bodied counterparts, were more cosmopolitan, radiating throughout much of Gondwana and paralleling the diversification of small coelurosaur theropods in Laurasia. PMID:11206544

Sampson, S D; Carrano, M T; Forster, C A

2001-01-25

97

Antibodies to haemorrhagic fever viruses in Madagascar populations.  

PubMed

Sera of 381 adult people from 5 areas in Madagascar were tested by the indirect immunofluorescence method for antibodies against Congo-Crimean haemorrhagic fever and Rift Valley fever viruses (Bunyaviridae), Ebola (strains Zaire and Sudan) and Marburg viruses (Filoviridae), and Lassa virus (Arenaviridae). The highest prevalence rate was that of Ebola virus (4.5%). As no haemorrhagic syndrome has been found associated with this virus, the possible presence of a less pathogenic, antigenically related, strain is discussed. The prevalences of Congo-Crimean haemorrhagic fever and Rift Valley viruses were very low, despite previous viral isolations from potential vectors. No serum reacted against Lassa or Marburg antigens. The results are analysed in the light of the geographical and bioecological characteristics of Madagascar, which is a true 'microcontinent' very different from the African mainland. PMID:2515626

Mathiot, C C; Fontenille, D; Georges, A J; Coulanges, P

1989-01-01

98

Molecular Analysis and Heterologous Expression of an Inducible Cytochrome P-450 Protein from Periwinkle (Catharanthus roseus L.) 1  

PubMed Central

We screened cDNA libraries from periwinkle (Catharanthus roseus) cell cultures induced for indole alkaloid synthesis and selected clones for induced cytochrome P-450 (P-450) proteins by differential hybridization, size of the hybridizing mRNA, and presence of amino acid motifs conserved in many P-450 families. Four cDNAs satisfying these criteria were analyzed in detail. They were grouped in two classes (pCros1, pCros2) that represented two closely related genes of a new P-450 family designated CYP72. Antiserum against a cDNA fusion protein overexpressed in Escherichia coli recognized in C. roseus a protein band of 56 kD. Quantification of western blots showed that it represented 1.5 ± 0.5 and 6 ± 1 ?g/mg of protein in the membranes from noninduced and induced cells, respectively, and analysis of the total P-450 content suggested that the cDNA-encoded protein was one of the dominant P-450 proteins. The pathway to indole alkaloids contains two known P-450 enzymes, geraniol-10-hydroxylase (GE10H) and nerol-10-hydroxylase (NE10H). The induction kinetics of the cloned P-450 protein and of GE10H activity were similar, but those of NE10H were different. Western blots with membranes from other plants suggested that P-450 CYP72 is specific for C. roseus and other plants with GE10H activity. A tentative assignment of CYP72 as GE10H is discussed. The cDNA was recloned for expression in Saccharomyces cerevisiae, and the presence of the protein was demonstrated by western blots. Assays for GE10H failed to detect enzyme activity, and the same negative result was obtained for NE10H and other P-450 enzymes that are present in C. roseus. Images Figure 5 Figure 7 PMID:16653087

Vetter, Hans-Peter; Mangold, Ursula; Schroder, Gudrun; Marner, Franz-Josef; Werck-Reichhart, Danielle; Schroder, Joachim

1992-01-01

99

Fire ecology and fire politics in Mali and Madagascar  

Microsoft Academic Search

\\u000a Anthropogenic fires dominate Africa, where they have long shaped landscapes and livelihoods. Humans evolved in Africa’s fire-prone\\u000a grasslands and savannas, eventually taking ignition into their own hands. This chapter reviews current knowledge about and\\u000a concerns over lire in two African countries. Mali and Madagascar. Vast areas of land burn in both countries each year as people\\u000a light fires to shape

Christian A. Kull; Paul Laris

100

Extinction Risks and the Conservation of Madagascar's Reptiles  

PubMed Central

Background An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Methodology/Principal Findings Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. Conclusions/Significance With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the island's biodiversity. PMID:25111137

Jenkins, Richard K. B.; Tognelli, Marcelo F.; Bowles, Philip; Cox, Neil; Brown, Jason L.; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R.; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D.; Hantalalaina, Elisoa F.; Glaw, Frank; Griffiths, Richard A.; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H.; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A.; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J. Christian; Randrianasolo, Harison H.; Randrianirina, Jasmin E.; Randrianizahana, Hiarinirina; Raselimanana, Achille P.; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M.; Raxworthy, Christopher J.; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P.; Yoder, Anne D.; Vences, Miguel

2014-01-01

101

Field Museum Researchers Help Trace Origin of Madagascar's Mammals  

NSDL National Science Digital Library

Chicago's Field Museum of Natural History (FMNH) Web site currently features museum-sponsored research on the phylogeny of Madagascar's living Carnivora. Previously thought to represent two to four separate lineages, the island's carnivores are now known to have descended from a single species. These findings, recently published in the journal Nature, are presented in the FMNH Web site as a 4-page press release that should appeal to general readers as well as interested researchers.

2003-01-01

102

Multiple Miocene Melastomataceae dispersal between Madagascar, Africa and India.  

PubMed Central

Melastomataceae sensu stricto (excluding Memecylaceae) comprise some 3000 species in the neotropics, 1000 in Asia, 240 in Africa, and 230 in Madagascar. Previous family-wide morphological and DNA analyses have shown that the Madagascan species belong to at least three unrelated lineages, which were hypothesized to have arrived by trans-oceanic dispersal. An alternative hypothesis posits that the ancestors of Madagascan, as well as Indian, Melastomataceae arrived from Africa in the Late Cretaceous. This study tests these hypotheses in a Bayesian framework, using three combined sequence datasets analysed under a relaxed clock and simultaneously calibrated with fossils, some not previously used. The new fossil calibration comes from a re-dated possibly Middle or Upper Eocene Brazilian fossil of Melastomeae. Tectonic events were also tentatively used as constraints because of concerns that some of the family's fossils are difficult to assign to nodes in the phylogeny. Regardless of how the data were calibrated, the estimated divergence times of Madagascan and Indian lineages were too young for Cretaceous explanations to hold. This was true even of the oldest ages within the 95% credibility interval around each estimate. Madagascar's Melastomeae appear to have arrived from Africa during the Miocene. Medinilla, with some 70 species in Madagascar and two in Africa, too, arrived during the Miocene, but from Asia. Gravesia, with 100 species in Madagascar and four in east and west Africa, also appears to date to the Miocene, but its monophyly has not been tested. The study afforded an opportunity to compare divergence time estimates obtained earlier with strict clocks and single calibrations, with estimates based on relaxed clocks and different multiple calibrations and taxon sampling. PMID:15519967

Renner, Susanne S

2004-01-01

103

Late Cretaceous elasmobranchs from the Mahajanga Basin of Madagascar  

Microsoft Academic Search

Recent collecting in the Mahajanga Basin of northwestern Madagascar has expanded our knowledge of Late Cretaceous elasmobranchs from the island. Mahajanga Basin exposures of the Upper Maastrichtian Berivotra Formation have produced teeth attributable to the following taxa: Pristiophorus sp. (Pristiophoriformes, Pristiophoridae);Parapalaeobates sp. (Rajiformes, Rhinobatidae); cf. Brachyrhizodus sp. (Rajiformes, Myliobatoidea);Carcharias sp. (Lamniformes, Odontaspididae);Squalicorax kaupi and S. pristodontus (Lamniformes, Anacoracidae); and Serratolamna

Michael D. Gottfried; Joseph A. Rabarison

2001-01-01

104

Xenopsylla cheopis (Siphonaptera: Pulicidae) Susceptibility to Deltamethrin in Madagascar  

PubMed Central

The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar. PMID:25369291

Elissa, Nohal

2014-01-01

105

Sporormiella and the late Holocene extinctions in Madagascar  

PubMed Central

Fossil spores of the dung fungus Sporormiella spp. in sediment cores from throughout Madagascar provide new information concerning megafaunal extinction and the introduction of livestock. Sporormiella percentages are very high in prehuman southwest Madagascar, but at the site with best stratigraphic resolution the spore declines sharply by ?1,720 yr B.P. (radiocarbon years ago). Within a few centuries there is a concomitant rise in microscopic charcoal that probably represents human transformation of the local environment. Reduced megaherbivore biomass in wooded savannas may have resulted in increased plant biomass and more severe fires. Some now-extinct taxa persisted locally for a millennium or more after the inferred megafaunal decline. Sites in closed humid forests of northwest Madagascar and a montane ericoid formation of the central highlands show only low to moderate Sporormiella percentages before humans. A subsequent rise in spore concentrations, thought to be evidence for livestock proliferation, occurs earliest at Amparihibe in the northwest at ?1,130 yr B.P. PMID:12960385

Burney, David A.; Robinson, Guy S.; Burney, Lida Pigott

2003-01-01

106

Xenopsylla cheopis (Siphonaptera: Pulicidae) Susceptibility to Deltamethrin in Madagascar.  

PubMed

The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar. PMID:25369291

Boyer, Sebastien; Miarinjara, Adélaïde; Elissa, Nohal

2014-01-01

107

Discovery of three new fungal species from dying Baobab trees in South Africa and Madagascar Prepared by Elsie Cruywagen  

E-print Network

of Capricorn in southern Africa. This species has also been introduced into Madagascar and other partsDiscovery of three new fungal species from dying Baobab trees in South Africa and Madagascar trees in the world. The eight known species of baobab belong to a single genus, Adansonia. Madagascar

108

A geological synthesis of the Precambrian shield in Madagascar  

USGS Publications Warehouse

Available U–Pb geochronology of the Precambrian shield of Madagascar is summarized and integrated into a synthesis of the region’s geological history. The shield is described in terms of six geodynamic domains, from northeast to southwest, the Bemarivo, Antongil–Masora, Antananarivo, Ikalamavony, Androyan–Anosyan, and Vohibory domains. Each domain is defined by distinctive suites of metaigneous rocks and metasedimentary groups, and a unique history of Archean (?2.5 Ga) and Proterozoic (?1.0 Ga, ?0.80 Ga, and ?0.55 Ga) reworking. Superimposed within and across these domains are scores of Neoproterozoic granitic stocks and batholiths as well as kilometer long zones of steeply dipping, highly strained rocks that record the effects of Gondwana’s amalgamation and shortening in latest Neoproterozoic time (0.560–0.520 Ga). The present-day shield of Madagascar is best viewed as part of the Greater Dharwar Craton, of Archean age, to which three exotic terranes were added in Proterozoic time. The domains in Madagascar representing the Greater Dharwar Craton include the Antongil–Masora domain, a fragment of the Western Dharwar of India, and the Neoarchean Antananarivo domain (with its Tsaratanana Complex) which is broadly analogous to the Eastern Dharwar of India. In its reconstructed position, the Greater Dharwar Craton consists of a central nucleus of Paleo-Mesoarchean age (>3.1 Ga), the combined Western Dharwar and Antongil–Masora domain, flanked by mostly juvenile “granite–greenstone belts” of Neoarchean age (2.70–2.56 Ga). The age of the accretionary event that formed this craton is approximately 2.5–2.45 Ga. The three domains in Madagascar exotic to the Greater Dharwar Craton are the Androyan–Anosyan, Vohibory, and Bemarivo. The basement to the Androyan–Anosyan domain is a continental terrane of Paleoproterozoic age (2.0–1.78 Ga) that was accreted to the southern margin (present-day direction) of the Greater Dharwar Craton in pre-Stratherian time (>1.6 Ga), and rejuvenated at 1.03–0.93 Ga with the creation of the Ikalamavony domain. The Vohibory domain, an oceanic terrane of Neoproterozoic age was accreted to the Androyan–Anosyan domain in Cryogenian time (?0.63–0.60 Ga). The Bemarivo domain of north Madagascar is a terrane of Cryogenian igneous rocks, with a cryptic Paleoproterozoic basement, that was accreted to the Greater Dharwar Craton in latest Ediacaran to earliest Cambrian time (0.53–0.51 Ga).

Tucker, Robert D.; Roig, J.Y.; Moine, B.; Delor, C.; Peters, S.G.

2014-01-01

109

The Catharanthus roseus 16-hydroxytabersonine O-methyltransferase involved in vindoline biosynthesis.  

E-print Network

??Madagascar periwinkle (Catharanthus roseus) produces the well known and remarkably complex dimeric anticancer alkaloids vinblastine and vincristine that are derived by coupling vindoline and catharanthine… (more)

Levac, Dylan.

2008-01-01

110

Reprogramming alkaloid biosynthesis in Catharanthus roseus : synthetic biology in plants .  

E-print Network

??The medicinal plant Madagascar periwinkle (Catharanthus roseus) produces over 130 monoterpene indole alkaloid (MIA) natural products. Many of these compounds have pharmaceutical value, such as… (more)

Runguphan, Weerawat

2011-01-01

111

Identification and characterization of a Catharanthus roseus mutant altered in monoterpenoid indole alkaloid biosynthesis.  

E-print Network

??The Madagascar periwinkle [Catharanthus roseus (L.) G. Don] is a commercially important horticultural flower species and is the only source for several pharmaceutically valuable monoterpenoid… (more)

Thamm, Antje MK

2014-01-01

112

A homolog of tocopherol C-methyltransferases catalyzes N-methylation in anticancer alkaloid biosynthesis  

E-print Network

Madagascar periwinkle (Catharanthus roseus) is the sole source of the anticancer drugs vinblastine and vincristine, bisindole alkaloids derived from the dimerization of the terpenoid indole alkaloids vindoline and ...

Liscombe, David K.

113

Taxonomic Revision of Mouse Lemurs (Microcebus) in the Western Portions of Madagascar  

Microsoft Academic Search

The genus Microcebus (mouse lemurs) are the smallest extant primates. Until recently, they were considered to comprise two different species: Microcebus murinus, confined largely to dry forests on the western portion of Madagascar, and M. rufus, occurring in humid forest formations of eastern Madagascar. Specimens and recent field observations document rufous individuals in the west. However, the current taxonomy is

Rodin M. Rasolooarison; Steven M. Goodman; Jörg U. Ganzhorn

2000-01-01

114

The antiquity of Madagascar's grasslands and the rise of C4 grassy biomes  

E-print Network

ORIGINAL ARTICLE The antiquity of Madagascar's grasslands and the rise of C4 grassy biomes William ­ that the grasslands are an insular example of the post-Miocene spread of C4 grassy biomes world-wide. Location with species endemic to Madagascar. Plant and animal species endemic to C4 grassy biomes would not be expected

Silander Jr., John A.

115

On the shoulders of lemurs: pinpointing the ecotouristic potential of Madagascar's unique herpetofauna  

Microsoft Academic Search

Based on 667 tourist interviews in five protected areas (PAs), carried out between January and September 2008, we assessed the ecotouristic potential of Madagascar's amphibians and reptiles compared with that of other components of its unique fauna. Visitors were best informed about mammals and reptiles, and information levels increased with subsequent visits to Madagascar. In contrast, tourists were not well

Katharina C. Wollenberg; Richard K. B. Jenkins; Roma Randrianavelona; Roseline Rampilamanana; Mahefa Ralisata; Andrianirina Ramanandraibe; Olga Ramilijaona Ravoahangimalala; Miguel Vences

2011-01-01

116

Deforestation history of the eastern rain forests of Madagascar from satellite images  

Microsoft Academic Search

Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain

G. M. Green; R. W. Sussman

1990-01-01

117

Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts  

ERIC Educational Resources Information Center

The Madagascar hissing cockroach ("Gromphadorhina portentosa") is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach…

Wagler, Ron

2009-01-01

118

Migration, isolation and hybridization in island crop populations: the case of Madagascar rice  

E-print Network

Migration, isolation and hybridization in island crop populations: the case of Madagascar rice, §T.T. Chang Genetic Resources Center, International Rice Research Institute, DAPO Box 7777, Metro or Asian rice is one of the key domesticated crop species in the world. The island of Madagascar off

Purugganan, Michael D.

119

Broken forest: Applying the integrated conservation and development paradigm to Madagascar's protected areas  

SciTech Connect

The destruction of Madagascar's primary forests through agricultural clearing poses a grave threat to the island's biodiversity. The report assesses the potential of the planned Sustainable and Viable Environmental Management (SAVEM) Project to minimize this threat by implementing Integrated Conservation Development Projects (ICDP's), which link resource conservation to income-generating activities, in the peripheral zones of Madagascar's protected areas.

Barbour, R.; Rabezandria, R.; Daviesson, R.; Guyton, W.; Rakotobe.

1992-06-01

120

Sustainable livelihoods and forest resources in Madagascar: a multi-scale analysis using remote sensing  

Microsoft Academic Search

Madagascar, as much of sub-Saharan Africa, suffers from highly variable and unpredictable climate, and human societies, as well as the natural ecosystems upon which they depend, have evolved and adapted to cope with this to some degree since humans populated the island some 2000 years BP. In Madagascar, humans are an integral component of most landscapes and, thus, may be

Terence P. Dawson; J. Carter Ingram

2008-01-01

121

[Trematode distribution in Littorina saxatilis populations can support the reproductive potential of the host: "toilers" and "idlers" among female periwinkles].  

PubMed

Co-evolution between parasites and their hosts can involve adaptations on the individual and population levels likely to be especially prominent in the systems where parasites have a direct strong impact on the hosts fitness, as is the case with castrating trematodes and their gastropod hosts. We studied populations of the rough periwinkles Littorina saxatilis in the White Sea infested by castrating trematodes to determine whether spatial and temporal variations in the trematode prevalence affect the demographic structure of the host population. Sex, age, reproductive status and infestation of L. saxatilis from 19 populations with different trematode burdens (from < 1 % to 30-50%); in two of these 19 populations (RI and KLN) a long-term monitoring over the period of 15-20 years was also performed. These analyses showed that (1) the average age of gravid females did not correlate with the trematode prevalence of the population, (2) the ratio was skewed towards females, (3) the trematode prevalence in females tended to be higher than in males, (4) the proportion of the non-infested gravid females of the younger ages classes (2-4 years) did not correlate with trematode prevalence of the population. The proportion of young non-infested females that were not reproducing ("idlers") decreased significantly with increasing infestation prevalence when compared among different populations of L. saxatilis, but remained relatively stable within two heavily infested populations RI and KLN despite the year-to-year fluctuations of the infestation prevalence. Thus, a demographic mechanism to compensate for the parasite pressure in L. saxatilis populations may involve the maintenance of a relatively constant proportion of uninfected gravid female ("toilers") at the expense of uninfected, but not reproducing females of fertile age ("idlers"); the latter can be viewed a reproductive reserve of the population tapped into under the conditions of high infestation prevalence. This mechanism, in combination with the previously described elevated individual fecundity of females in heavily infested populations, may compensate for the parasite-induced decrease in the reproductive potential of the host population and ensure the stability of the host-parasite system. PMID:23458020

Granovich, A I; Iagunova, E B; Sokolova, I M

2012-01-01

122

A double-flowered variety of lesser periwinkle (Vinca minor fl. pl.) that has persisted in the wild for more than 160 years  

PubMed Central

Background and Aims Homeotic transitions are usually dismissed by population geneticists as credible modes of evolution due to their assumed negative impact on fitness. However, several lines of evidence suggest that such changes in organ identity have played an important role during the origin and subsequent evolution of the angiosperm flower. Better understanding of the performance of wild populations of floral homeotic varieties should help to clarify the evolutionary potential of homeotic mutants. Wild populations of plants with changes in floral symmetry, or with reproductive organs replacing perianth organs or sepals replacing petals have already been documented. However, although double-flowered varieties are quite popular as ornamental and garden plants, they are rarely found in the wild and, if they are, usually occur only as rare mutant individuals, probably because of their low fitness relative to the wild-type. We therefore investigated a double-flowered variety of lesser periwinkle, Vinca minor flore pleno (fl. pl.), that is reported to have existed in the wild for at least 160 years. To assess the merits of this plant as a new model system for investigations on the evolutionary potential of double-flowered varieties we explored the morphological details and distribution of the mutant phenotype. Methods The floral morphology of the double-flowered variety and of a nearby population of wild-type plants was investigated by means of visual inspection and light microscopy of flowers, the latter involving dissected or sectioned floral organs. Key Results The double-flowered variety was found in several patches covering dozens of square metres in a forest within the city limits of Jena (Germany). It appears to produce fewer flowers than the wild-type, and its flowers are purple rather than blue. Most sepals in the first floral whorl resemble those in the wild-type, although occasionally one sepal is broadened and twisted. The structure of second-whorl petals is very similar to that of the wild-type, but their number per flower is more variable. The double-flowered character is due to partial or complete transformation of stamens in the third whorl into petaloid organs. Occasionally, ‘flowers within flowers’ also develop on elongated pedicels in the double-flowered variety. Conclusions The flowers of V. minor fl. pl. show meristic as well as homeotic changes, and occasionally other developmental abnormalities such as mis-shaped sepals or loss of floral determinacy. V. minor fl. pl. thus adds to a growing list of natural floral homeotic varieties that have established persistent populations in the wild. Our case study documents that even mutant varieties that have reproductive organs partially transformed into perianth organs can persist in the wild for centuries. This finding makes it at least conceivable that even double-flowered varieties have the potential to establish new evolutionary lineages, and hence may contribute to macroevolutionary transitions and cladogenesis. PMID:21527418

Wang, Yong-Qiang; Melzer, Rainer; Theissen, Gunter

2011-01-01

123

Les aspergillomes pulmonaires: ? propos de 37 cas ? Madagascar  

PubMed Central

L'aspergillome pulmonaire est une colonisation par Aspergillus d'une cavité pulmonaire préformée. Nos objectifs étaient de définir le profil épidémio-clinique et thérapeutique des aspergillomes pulmonaires et essayer de dégager les facteurs favorisants de cette affection à Madagascar. Nous avons réalisés une étude prospective, descriptive, analytique durant 59 mois sur les aspergillomes pulmonaires à Antananarivo Madagascar. Etaient inclus dans cette étude les malades ayant un diagnostic d'aspergillome pulmonaire. Trente-sept (37) cas d'aspergillome pulmonaire étaient recensés parmi les 8 392 patients hospitalisés dans le service de Pneumologie (0,44%). Il s'agit de 29 hommes (78,38%) et 8 femmes (21,61%), d’âge moyen de 43 ans. Les facteurs prédisposant étaient dominés par la tuberculose pulmonaire (89,19%). Le délai moyen d'apparition de l'aspergillome chez les malades ayant un antécédent de tuberculose pulmonaire à bacilloscopie positive (TPM+) était de 8 ans et 6 mois avec un délai extrême de un mois à 23 ans. L'hémoptysie était le mode de révélation le plus fréquent (91,89%). Le traitement était médical chez 27 patients (72,97%) et médico-chirurgical chez 10 patients (27,03%). Vingt sept patients étaient perdus de vue (72,97%), et pour les 10 patients suivis (27,02%), 70% avaient une évolution favorable avec disparition des signes, et 30% présentaient des hémoptysies récidivantes. Le taux de mortalité postopératoire était de 4% et 50% des patients avaient des complications postopératoires. La surveillance des lésions séquellaires de tuberculose pulmonaire qui constituent les facteurs favorisants prédominant d'aspergillome pulmonaire à Madagascar nécessite une attention particulière. La prise en charge de la tuberculose doit être précoce et adaptée surtout dans les pays à forte prévalence tuberculeuse. PMID:22187586

Rakotoson, Joelson Lovaniaina; Razafindramaro, Notahiana; Rakotomizao, Jocelyn Robert; Vololontiana, Hanta Marie Danielle; Andrianasolo, Radonirina Lazasoa; Ravahatra, Kiady; Tiaray, Michel; Rajaoarifetra, Jobeline; Rakotoharivelo, Hendriniaina; Andrianarisoa, Ange Christophe Felix

2011-01-01

124

[AIDS in Madagascar. I. Epidemiology, projections, socioeconomic impact, interventions].  

PubMed

Madagascar is still among the rare states of low prevalence of HIV. The seroprevalence rate is nevertheless rising. The aim of this study is to show the current view of the epidemic, its future tendency, its economical and social impact on people and what measures to be taken at the national scale. In Madagascar, we can state by 1995 20 cases of notified AIDS and probably 130 cases of non-notified AIDS. Seroprevalence data are collected every year by the National Reference Laboratory STD/AIDS. But, they are insufficient to estimate the number of infected people. So, they had been completed by a serosurveillance study of AIDS and syphilis in middle of 1995 and at the beginning of 1996. Pregnant women, persons with STDs and prostitutes are been screened in the six biggest cities of the Island. Results show, not only a high prevalence of syphilis, but also indicate that now, we have about 5,000 seropositive people in the country. Besides, by the number of people with STDs, it is estimated that one million Malgasy adults risk to be infected. Based on estimates of the epidemic, be it the cases of a high scenario, (Kenya) or of a low one (Thailand) by the year 2015, the seroprevalence rate could represent 3% or 15% of adults. Demographic consequences of the epidemic will be serious, particularly if HIV spreads quickly. Nevertheless, it does not stop the increase of population. Therefore, there will be more infected people with the disease, especially young people between 15 and 49 years old. The increase of dead people will be serious. Social consequences of the epidemic (case of high scenario) will be gravely felt, in particular by the rise of the number of AIDS orphans. Tuberculosis outbreak can be observed too. This disease is already a serious problem in Madagascar. At last, the epidemic will bring with it a high increase of money spent on health and will have grave consequences on agriculture, industry and commerce. Nevertheless, Madagascar still benefit a big luck which is the prevention of the epidemic not to be exploded in a near future. For this, struggle against it is particularly effective on its start. In addition to counselling given to infected people and care-given to patients, means of prevention of AIDS contamination in all target groups must be set up quickly. It is about broadcasting information on AIDS, community education, controlling other STDs e.g. (importance of medicaments' program), promoting the use of condoms and screening HIV new cases. Only an urgent coordination of everyone's efforts can control the epidemic of AIDS. PMID:9559168

Andriamahenina, R; Ravelojaona, B; Rarivoharilala, E; Ravaoarimalala, C; Andriamiadana, J; Andriamahefazafy, B; May, J F; Behets, F; Rasamindrakotroka, A

1998-01-01

125

The value of small size: loss of forest patches and ecological thresholds in southern Madagascar.  

PubMed

Many services generated by forest ecosystems provide essential support for human well-being. However, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. We present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern Madagascar. Two ecosystem services dependent on the forest habitats were addressed: (1) crop pollination services by wild and semidomesticated bees (Apoidea), essential for local crop production of, for example, beans, and (2) seed dispersal services based on the presence of ring-tailed lemurs (Lemur catta). We studied the vulnerability of these ecosystem services to a plausible scenario of successive destruction of the smallest habitat patches. Our results indicate that, in spite of the fragmented nature of the landscape, the fraction of the landscape presently covered by both crop pollination and seed dispersal services is surprisingly high. It seems that the taboo system, though indirectly and unintentionally, contributes to upholding the generation of these services by protecting the forest patches. Both services are, however, predicted to be very vulnerable to the successive removal of small patches. For crop pollination, the rate of decrease in cover was significant even when only the smallest habitat patches were removed. The capacity for seed dispersal across the landscape displayed several thresholds with habitat patch removal. Our results suggest that, in order to maintain capacity for seed dispersal across the landscape and crop pollination cover in southern Androy, the geographical location of the remaining forest patches is more crucial than their size. We argue that in heavily fragmented production landscapes, small forest patches should increasingly be viewed as essential for maintaining ecosystem services, such as agricultural production, and also should be considered in the ongoing process of tripling the area of protected habitats in Madagascar. PMID:16711035

Bodin, Orjan; Tengö, Maria; Norman, Anna; Lundberg, Jakob; Elmqvist, Thomas

2006-04-01

126

Defining and explaining tropical deforestation: shifting cultivation and population growth in colonial Madagascar (1896-1940).  

PubMed

The case study of deforestation in Madagascar demonstrated how deforestation is a complex phenomenon that reflects interconnections between land-based resources, human groups, and global political economy; specifically, there is a link between changing land use practices affecting shifting cultivation and tropical deforestation. The general development model of exponential population growth and shifting cultivation causing deforestation and environmental degradation is too simplified, places undue blame on the victims, and isolates shifting cultivation practices from the reality of land use patterns in specific places at specific times. Problematic also is the way definition, delimitation, and discussion of environmental problems shapes possible solutions. This analysis suggests a theoretical view that links reconstructed regional geography with political ecology. The assertion is that deforestation is historically based on multiple social processes within Madagascar. Land use practices and resource access decisions during the colonial period affected land management and degradation. The colonial state policy played a role in the destruction of tropical flora by fire, shifting cultivation, and grazing, and the responses of Europeans and Malagasys. Context and multiplicity of motivations and practices were key. A review was presented of reconstructed regional geography and political ecology and global tropical deforestation. The description of the political economy of deforestation during colonial times focused on the movement of population into the forests after 1896 and French annexation. Famine resulted. Shifting cultivation laws were passed between 1881 and 1913, due to the desire for rational forest resource management. Ecologically and socially these rules were difficult to enforce; there were resistance due to the threat of the elimination of subsistence living for wage work. Destructive logging practices and forest product extraction after 1921 are described. During 1900-1941, population was below or at replacement level, but the government still blamed Malagasys. Shifting cultivation meant different things to the subsistence farmers, the state, and international agencies. Denial of context promotes an ideology of repression, fuels fear and prejudice, and promotes the wrong solutions. PMID:12318844

Jarosz, L

1993-10-01

127

Proterozoic tectonostratigraphy and paleogeography of central Madagascar derived from detrital zircon U-Pb age populations  

USGS Publications Warehouse

Detrital zircon U-Pb ages determined by SHRIMP distinguish two clastic sequences among Proterozoic metasedimentary rocks from central Madagascar. The Itremo Group is older: zircon data, stromatolite characteristics, and carbon isotope data all point to a depositional age around 1500-1700 Ma. The Molo Group is younger, deposited between ???620 Ma (the age of the youngest zircon) and ???560 Ma (the age of metamorphic overgrowths on detrital cores). Geochronologic provenance analysis of the Itremo Group points to sources in East Africa as well as local sources in central and southern Madagascar but provides no evidence for a detrital contribution from northern and eastern Madagascar nor from southern India. Detrital zircon and sedimentologic similarities between rocks of the Itremo Group and the Zambian Muva Supergroup suggest a lithostratigraphic correlation between the two. The Molo Group has a strong 1000-1100 Ma detrital signature that also indicates an east African provenance and suggests a Neoproterozoic geographic connection with Sri Lanka but shows no indication of input from the Dharwar craton and eastern Madagascar. Central Madagascar was probably juxtaposed with the Tanzanian craton in the Paleo- and Mesoproterozoic, whereas northern and eastern Madagascar were connected to India. Internal assembly of Madagascar postdates Neoproterozoic Molo Group sedimentation and is likely to have occurred at about 560 Ma. ?? 2004 by The University of Chicago. All rights reserved.

Cox, R.; Coleman, D. S.; Chokel, C. B.; DeOreo, S. B.; Wooden, J. L.; Collins, A. S.; De Waele, B.; Kroner, A.

2004-01-01

128

A Non-Stationary Relationship between Global Climate Phenomena and Human Plague Incidence in Madagascar  

PubMed Central

Background Plague, a zoonosis caused by Yersinia pestis, is found in Asia and the Americas, but predominantly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. Plague's occurrence is affected by local climate factors which in turn are influenced by large-scale climate phenomena such as the El Niño Southern Oscillation (ENSO). The effects of ENSO on regional climate are often enhanced or reduced by a second large-scale climate phenomenon, the Indian Ocean Dipole (IOD). It is known that ENSO and the IOD interact as drivers of disease. Yet the impacts of these phenomena in driving plague dynamics via their effect on regional climate, and specifically contributing to the foci of transmission on Madagascar, are unknown. Here we present the first analysis of the effects of ENSO and IOD on plague in Madagascar. Methodology/principal findings We use a forty-eight year monthly time-series of reported human plague cases from 1960 to 2008. Using wavelet analysis, we show that over the last fifty years there have been complex non-stationary associations between ENSO/IOD and the dynamics of plague in Madagascar. We demonstrate that ENSO and IOD influence temperature in Madagascar and that temperature and plague cycles are associated. The effects on plague appear to be mediated more by temperature, but precipitation also undoubtedly influences plague in Madagascar. Our results confirm a relationship between plague anomalies and an increase in the intensity of ENSO events and precipitation. Conclusions/significance This work widens the understanding of how climate factors acting over different temporal scales can combine to drive local disease dynamics. Given the association of increasing ENSO strength and plague anomalies in Madagascar it may in future be possible to forecast plague outbreaks in Madagascar. The study gives insight into the complex and changing relationship between climate factors and plague in Madagascar. PMID:25299064

Kreppel, Katharina S.; Caminade, Cyril; Telfer, Sandra; Rajerison, Minoarison; Rahalison, Lila; Morse, Andy; Baylis, Matthew

2014-01-01

129

Biogeography of the two major arbovirus mosquito vectors, Aedes aegypti and Aedes albopictus (Diptera, Culicidae), in Madagascar  

PubMed Central

Background In the past ten years, the Indian Ocean region has been the theatre of severe epidemics of chikungunya and dengue. These outbreaks coincided with a high increase in populations of Aedes albopictus that outcompete its sister taxon Aedes aegypti in most islands sampled. The objective of this work was to update the entomological survey of the two Aedes species in the island of Madagascar which has to face these arboviroses. Methods The sampling of Aedes mosquitoes was conducted during two years, from October 2007 to October 2009, in fifteen localities from eight regions of contrasting climates. Captured adults were identified immediately whereas immature stages were bred until adult stage for determination. Phylogenetic analysis was performed using two mtDNA genes, COI and ND5 and trees were constructed by the maximum likelihood (ML) method with the gene time reversible (GTR) model. Experimental infections with the chikungunya virus strain 06.21 at a titer of 107.5 pfu/mL were performed to evaluate the vector competence of field-collected mosquitoes. Disseminated infection rates were measured fourteen days after infection by immunofluorescence assay performed on head squashes. Results The species Aedes aegypti was detected in only six sites in native forests and natural reserves. In contrast, the species Aedes albopictus was found in 13 out of the 15 sites sampled. Breeding sites were mostly found in man-made environments such as discarded containers, used tires, abandoned buckets, coconuts, and bamboo cuts. Linear regression models showed that the abundance of Ae. albopictus was significantly influenced by the sampling region (F = 62.00, p < 2.2 × 10-16) and period (F = 36.22, p = 2.548 × 10-13), that are associated with ecological and climate variations. Phylogenetic analysis of the invasive Ae. albopictus distinguished haplotypes from South Asia and South America from those of Madagascar, but the markers used were not discriminant enough to discern Malagasy populations. The experimental oral infection method showed that six Ae. albopictus populations exhibited high dissemination infection rates for chikungunya virus ranging from 98 to 100%. Conclusion In Madagascar, Ae. albopictus has extended its geographical distribution whereas, Ae. aegypti has become rare, contrasting with what was previously observed. Changes are predominantly driven by human activities and the rainfall regime that provide suitable breeding sites for the highly anthropophilic mosquito Ae. albopictus. Moreover, these populations were found to be highly susceptible to chikungunya virus. In the light of this study, Ae. albopictus may have been involved in the recent outbreaks of chikungunya and dengue epidemics in Madagascar, and consequently, control measures should be promoted to limit its current expansion. PMID:22433186

2012-01-01

130

Salicylic acid mitigates salinity stress by improving antioxidant defence system and enhances vincristine and vinblastine alkaloids production in periwinkle [ Catharanthus roseus (L.) G. Don  

Microsoft Academic Search

A pot experiment was conducted to find out whether the foliar spray of salicylic acid (SA) could successfully ameliorate the\\u000a adverse effects of salinity stress on periwinkle. Thirty-day-old plants were supplied with Control; 0 mM NaCl + 10?5 M SA (T1); 50 mM NaCl + 0 SA (T2); 100 mM NaCl + 0 SA (T3); 150 mM NaCl + 0 SA (T4); 50 mM NaCl + 10?5 M SA (T5); 100 mM NaCl + 10?5 M SA (T6); 150 mM NaCl + 10?5 M SA

Mohd Idrees; M. Naeem; Tariq Aftab; M. Masroor A. Khan; Moinuddin

2011-01-01

131

Mangrove Forest Distributions and Dynamics in Madagascar (1975-2005)  

PubMed Central

Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ± one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ?2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%).

Giri, Chandra; Muhlhausen, Joseph

2008-01-01

132

Phylogeographic analysis of the true lemurs (genus Eulemur) underlines the role of river catchments for the evolution of micro-endemism in Madagascar  

PubMed Central

Introduction Due to its remarkable species diversity and micro-endemism, Madagascar has recently been suggested to serve as a biogeographic model region. However, hypothesis-based tests of various diversification mechanisms that have been proposed for the evolution of the island’s micro-endemic lineages are still limited. Here, we test the fit of several diversification hypotheses with new data on the broadly distributed genus Eulemur using coalescent-based phylogeographic analyses. Results Time-calibrated species tree analyses and population genetic clustering resolved the previously polytomic species relationships among eulemurs. The most recent common ancestor of eulemurs was estimated to have lived about 4.45 million years ago (mya). Divergence date estimates furthermore suggested a very recent diversification among the members of the “brown lemur complex”, i.e. former subspecies of E. fulvus, during the Pleistocene (0.33-1.43 mya). Phylogeographic model comparisons of past migration rates showed significant levels of gene flow between lineages of neighboring river catchments as well as between eastern and western populations of the redfronted lemur (E. rufifrons). Conclusions Together, our results are concordant with the centers of endemism hypothesis (Wilmé et al. 2006, Science 312:1063–1065), highlight the importance of river catchments for the evolution of Madagascar’s micro-endemic biota, and they underline the usefulness of testing diversification mechanisms using coalescent-based phylogeographic methods. PMID:24228694

2013-01-01

133

STUDY OF LAND USE ISSUES CHARACTERIZING THE AMBALAVAO-ANDRINGITRA REGION OF MADAGASCAR  

EPA Science Inventory

EPA Identifier: GF9500572 Title: Study of Land Use Issues Characterizing the Ambalavao-Andringitra Region of Madagascar Fellow (Principal Investigator): Christian Arthur Kull Institution: University of Colorado EPA Grant Representati...

134

Madagascar Flatidae (Hemiptera, Fulgoromorpha): state-of-the-art and research challenges  

PubMed Central

Abstract The paper provides a historical review of the research on Flatidae in Madagascar and indicates future prospects. While the first two species of Madagascar Flatidae were described by Guérin-Méneville (1844), it was Signoret (1860) who made the first real attempt to enhance our knowledge of the Hemiptera fauna of Madagascar by describing several additional species. Over the following century and a half, several investigators have turned their attention to this group of insects, with the final number of species recorded for the island reaching 79. Despite this long history of research, it is evident that much still remains to be done. Detailed taxonomic research will allow the natural history of Madagascar and changes in the biological diversity of its endemic ecosystems to be better understood. This paper should be considered as an introduction to a complex study on the systematics and phylogeny of worldwide Flatidae planthoppers. PMID:24039526

Swierczewski, Dariusz; Stroinski, Adam

2013-01-01

135

THE FOOD HABITS OF THE BARN OWL TYTO ALBA AT THREE SITES ON MADAGASCAR  

Microsoft Academic Search

Goodman, S. M., Langrand, O. & Raxworthy, C. J. 1993. The food habits of the Barn Owl Tyro alba at three sites on Madagascar. Ostrich 64:160-171.Regurgitated food remains of the Barn Owl Tyro alba were collected within the rain forest of the Eastern Region of Madagascar (Andasibe and Manombo) and in the sub-arid thorn scrub of the Western Region (Beza

Steven M. Goodman; Olivier Langrand; Christopher J. Raxworthy

1993-01-01

136

An economic analysis of deforestation in Madagascar in the 1990s  

Microsoft Academic Search

Madagascar is well-known among conservationists for both its unique forest ecosystems and its alarmingly high rates of deforestation. This paper studies the factors driving deforestation in Madagascar using a nation-wide data set of commune-level variables. The analysis suggests that higher population and fertility rates were associated with higher deforestation in the moist forest region in the 1990s. Deforestation was lower

Christine Moser

2008-01-01

137

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle  

Microsoft Academic Search

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite

JEFF A. JOHNSON; RUTH E. TINGA; MELANIE CULVER; FRANK HAILER

2009-01-01

138

Oceanic variability around Madagascar : connections to the large-scale Indian Ocean circulation and its forcing  

Microsoft Academic Search

The connection between the mesoscale eddy activity around Madagascar and the large-scale interannual variability in the Indian Ocean is investigated. We use the combined TOPEX\\/Poseidon-ERS sea surface height (SSH) data for the period 1993-2003. The SSH-fields in the Mozambique Channel and east of Madagascar exhibit a significant interannual oscillation. This is related to the arrival of large-scale anomalies that propagate

V. Palastanga

2007-01-01

139

U-Pb zircon geochronology and geochemistry of Late Jurassic basalts in Maevatanana, Madagascar: Implications for the timing of separation of Madagascar from Africa  

NASA Astrophysics Data System (ADS)

Magmatic zircon ages for the Maevatanana basalts in Madagascar indicate that Madagascar separated from Africa at 149.8 ± 2.1 Ma. Rocks produced by this basaltic magmatism associated with rifting are characterized by low SiO2 (49.6-50.3 wt.%), high total FeO (>13.9 wt.%), TiO2 (>3.7 wt.%), and P2O5 (>0.5 wt.%), and extremely high Na2O/K2O (3.08-3.27). Geochemical variations can be ascribed to significant fractional crystallization of clinopyroxene and plagioclase. The mineralogical and geochemical characteristics of the Maevatanana basalts suggest affinities with calc-alkaline basalt. Additionally the basalts have distinct ocean-island-basalt-like geochemical features that may be related to the Marion plume. We speculate that the Maevatanana basalts are the product of the Marion mantle plume related to separation of Madagascar from Africa in the Late Jurassic.

Yang, Xi-An; Chen, Yu-Chuan; Hou, Ke-Jun; Liu, Shan-Bao; Liu, Jia-Jun

2014-12-01

140

Spatial and temporal arrival patterns of Madagascar's vertebrate fauna explained by distance, ocean currents, and ancestor type  

PubMed Central

How, when, and from where Madagascar's vertebrates arrived on the island is poorly known, and a comprehensive explanation for the distribution of its organisms has yet to emerge. We begin to break that impasse by analyzing vertebrate arrival patterns implied by currently existing taxa. For each of 81 clades, we compiled arrival date, source, and ancestor type (obligate freshwater, terrestrial, facultative swimmer, or volant). We analyzed changes in arrival rates, with and without adjusting for clade extinction. Probability of successful transoceanic dispersal is negatively correlated with distance traveled and influenced by ocean currents and ancestor type. Obligate rafters show a decrease in probability of successful transoceanic dispersal from the Paleocene onward, reaching the lowest levels after the mid-Miocene. This finding is consistent with a paleoceanographic model [Ali JR, Huber M (2010) Nature 463:653–656] that predicts Early Cenozoic surface currents periodically conducive to rafting or swimming from Africa, followed by a reconfiguration to present-day flow 15–20 million years ago that significantly diminished the ability for transoceanic dispersal to Madagascar from the adjacent mainland. PMID:22431643

Samonds, Karen E.; Godfrey, Laurie R.; Ali, Jason R.; Goodman, Steven M.; Vences, Miguel; Sutherland, Michael R.; Irwin, Mitchell T.; Krause, David W.

2012-01-01

141

Intraseasonal Variability of Convection over Southern Africa and Madagascar  

NASA Astrophysics Data System (ADS)

Southern Africa and Madagascar regions delimited respectively by 5S-30S; 25E-40E, and 15S-25S; 42E-50E are considered. Those regions are climatologically wet and are considerably under the influence of the tropical cyclone activity in the southwest Indian Ocean. Periods of wet or dry conditions lasting several days may affect the annual rainfall regime and ultimately impact economy and public health. In this study, NCEP-NCAR Reanalysis data and cold cloud duration data are used to investigate the atmospheric circulation patterns and moisture field associated with wet and dry spells for the 2000-2001 and 2001-2002 rainy seasons. This work is supported by the Department of Commerce and NOAA.

Robjhon, M. L.; Thiaw, W. M.; Joseph, E.

2002-05-01

142

Migration, isolation and hybridization in island crop populations: the case of Madagascar rice.  

PubMed

Understanding how crop species spread and are introduced to new areas provides insights into the nature of species range expansions. The domesticated species Oryza sativa or Asian rice is one of the key domesticated crop species in the world. The island of Madagascar off the coast of East Africa was one of the last major Old World areas of introduction of rice after the domestication of this crop species and before extensive historical global trade in this crop. Asian rice was introduced in Madagascar from India, the Malay Peninsula and Indonesia approximately 800-1400 years ago. Studies of domestication traits characteristic of the two independently domesticated Asian rice subspecies, indica and tropical japonica, suggest two major waves of migrations into Madagascar. A population genetic analysis of rice in Madagascar using sequence data from 53 gene fragments provided insights into the dynamics of island founder events during the expansion of a crop species' geographic range and introduction to novel agro-ecological environments. We observed a significant decrease in genetic diversity in rice from Madagascar when compared to those in Asia, likely the result of a bottleneck on the island. We also found a high frequency of a unique indica type in Madagascar that shows clear population differentiation from most of the sampled Asian landraces, as well as differential exchange of alleles between Asia and Madagascar populations of the tropical japonica subspecies. Finally, despite partial reproductive isolation between japonica and indica, there was evidence of indica/japonica recombination resulting from their hybridization on the island. PMID:20964753

Mather, Kristie A; Molina, Jeanmaire; Flowers, Jonathan M; Rubinstein, Samara; Rauh, Brad L; Lawton-Rauh, Amy; Caicedo, Ana L; McNally, Kenneth L; Purugganan, Michael D

2010-11-01

143

41ZOOSYSTEMA 2002 24 (1) Publications Scientifiques du Musum national d'Histoire naturelle, Paris. www.mnhn.fr/publication/ The freshwater crabs of Madagascar  

E-print Network

, Paris. www.mnhn.fr/publication/ The freshwater crabs of Madagascar (Crustacea, Decapoda, Potamoidea. -- The freshwater crabs of Madagascar (Crustacea, Decapoda, Potamoidea). Zoosystema 24 (1) : 41-79. ABSTRACT The taxonomy of the freshwater crabs of Madagascar is revised and the num- ber of genera raised from five

Cumberlidge, Neil

144

Education and Training in Madagascar: Toward a Policy Agenda for Economic Growth and Poverty Reduction. A World Bank Country Study.  

ERIC Educational Resources Information Center

Madagascar is a poor, primarily rural country in which three-quarters of the population has subsisted below the poverty line for at least two decades. In view of the important role of education in the government's poverty reduction agenda, this report documents the current status of educational development in Madagascar and the key constraints on…

World Bank, Washington, DC.

145

In and out of Madagascar: Dispersal to Peripheral Islands, Insular Speciation and Diversification of Indian Ocean Daisy Trees (Psiadia, Asteraceae)  

Microsoft Academic Search

Madagascar is surrounded by archipelagos varying widely in origin, age and structure. Although small and geologically young, these archipelagos have accumulated disproportionate numbers of unique lineages in comparison to Madagascar, highlighting the role of waif-dispersal and rapid in situ diversification processes in generating endemic biodiversity. We reconstruct the evolutionary and biogeographical history of the genus Psiadia (Asteraceae), a plant genus

Joeri S. Strijk; Richard D. Noyes; Dominique Strasberg; Corinne Cruaud; Fredéric Gavory; Mark W. Chase; Richard J. Abbott; Christophe Thébaud

2012-01-01

146

Elaphoglossum nidusoides (Dryopteridaceae), a New Species of Fern from Madagascar with an Unusual Phylogenetic Position in the  

E-print Network

Elaphoglossum nidusoides (Dryopteridaceae), a New Species of Fern from Madagascar with an Unusual.S.A. 4 Author for correspondence (rouhan@mnhn.fr) Communicating Editor: Mark P. Simmons ABSTRACT. A fern by the succulent fronds. KEYWORDS: Elaphoglossum, fern, Madagascar, new species, phylogeny, Squamipedia

147

ASSESSING FLAVIVIRUS, LENTIVIRUS, AND HERPESVIRUS EXPOSURE IN FREE-RANGING RING-TAILED LEMURS IN SOUTHWESTERN MADAGASCAR  

Microsoft Academic Search

The ring-tailed lemur (Lemur catta) is an endangered species found in southwestern Madagascar, and understanding infectious disease susceptibility is an essential step towards the preservation of wild and captive lemur populations. Lemurs are primates that are widely dispersed throughout the island of Madagascar and may serve as hosts or reservoirs for zoonotic infections. The aim of this study was to

Kerry Sondgeroth; Brad Blitvich; Carol Blair; Julie Terwee; Randall Junge; Michelle Sauther; Sue VandeWoude

148

Influence of Dry Season and Food Quality and Quantity on Behavior and Feeding Strategy of Propithecus verreauxi in Kirindy, Madagascar  

Microsoft Academic Search

According to optimal foraging theory, herbivores can base food choice mainly on the quality or the quantity of food, or both. Among herbivorous primates, folivorous lemurs living in the highly seasonal environment of Madagascar have to cope with the shortage of high-quality food during the dry season, at least in deciduous forests. We studied (Verreaux's sifaka) in Kirindy, western Madagascar,

Ivan Norscia; Valentina Carrai; Silvana M. Borgognini-Tarli

2006-01-01

149

Poverty reduction and Millennium Development Goals: recognizing population, health, and environment linkages in rural Madagascar.  

PubMed

The Millennium Development Goals (MDGs), committed to by all 191 United Nations member states, are rooted in the concept of sustainable development. Although 2007 (midway) reports indicated that programs are under way, unfortunately many countries are unlikely to reach their goals by 2015 due to high levels of poverty. Madagascar is one such example, although some gains are being made. Attempts of this island nation to achieve its MDGs, expressed most recently in the form of a Madagascar Action Plan, are notable in their emphasis on (1) conserving the country's natural resource base, (2) the effect of demographic trends on development, and (3) the importance of health as a prerequisite for development. Leadership in the country's struggle for economic growth comes from the president of the Republic, in part, through his "Madagascar Naturally" vision as well as his commitment to universal access to family planning, among other health and development interventions. However, for resource-limited countries, such as Madagascar, to get or stay "on track" to achieving the MDGs will require support from many sides. "Madagascar cannot do it alone and should not do it alone." This position is inherent in the eighth MDG: "Develop a global partnership for development." Apparently, it takes a village after all - a global one. PMID:18311367

Gaffikin, Lynne; Ashley, Jeffrey; Blumenthal, Paul D

2007-01-01

150

Presence of the amphibian chytrid fungus Batrachochytrium dendrobatidis in native amphibians exported from Madagascar.  

PubMed

The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented. PMID:24599336

Kolby, Jonathan E

2014-01-01

151

Presence of the Amphibian Chytrid Fungus Batrachochytrium dendrobatidis in Native Amphibians Exported from Madagascar  

PubMed Central

The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented. PMID:24599336

Kolby, Jonathan E.

2014-01-01

152

Forecasting deforestation and carbon emissions in tropical developing countries facing demographic expansion: a case study in Madagascar.  

PubMed

Anthropogenic deforestation in tropical countries is responsible for a significant part of global carbon dioxide emissions in the atmosphere. To plan efficient climate change mitigation programs (such as REDD+, Reducing Emissions from Deforestation and forest Degradation), reliable forecasts of deforestation and carbon dioxide emissions are necessary. Although population density has been recognized as a key factor in tropical deforestation, current methods of prediction do not allow the population explosion that is occurring in many tropical developing countries to be taken into account. Here, we propose an innovative approach using novel computational and statistical tools, including R/GRASS scripts and the new phcfM R package, to model the intensity and location of deforestation including the effect of population density. We used the model to forecast anthropogenic deforestation and carbon dioxide emissions in five large study areas in the humid and spiny-dry forests of Madagascar. Using our approach, we were able to demonstrate that the current rapid population growth in Madagascar (+3.39% per year) will significantly increase the intensity of deforestation by 2030 (up to +1.17% per year in densely populated areas). We estimated the carbon dioxide emissions associated with the loss of aboveground biomass to be of 2.24 and 0.26 tons per hectare and per year in the humid and spiny-dry forest, respectively. Our models showed better predictive ability than previous deforestation models (the figure of merit ranged from 10 to 23). We recommend this approach to reduce the uncertainty associated with deforestation forecasts. We also underline the risk of an increase in the speed of deforestation in the short term in tropical developing countries undergoing rapid population expansion. PMID:23789079

Vieilledent, Ghislain; Grinand, Clovis; Vaudry, Romuald

2013-06-01

153

[Water and environment in the Southwest of Madagascar].  

PubMed

The dry and arid southwest region of Madagascar is not a desert but resembles the Sahel region of West Africa. The chronic water deficit is aggravated by the heat and constant winds that accelerate evapotranspiration on the permeable soils. The dryness occurs because the southwest region lies outside the main pluviogenic systems. Erosion occurs at all seasons. In the winter the sun and winds are the main causes, while the rare storms are more conducive to run-off and to erosion than to absorption. The acute water shortage in the southwest has prompted hydrogeologic research and well-drilling, but the high salt content of the water and other impurities will be a limiting factor for development of the area. The population of the southwest is extremely mobile. Human settlements are concentrated in the valleys and depressions and along major roads. Customary rights to land under the control of the traditional chiefs regulate tenure in most areas. But especially in the river bottoms, the coming of cash crops cultivated with modern equipment has resulted in significant erosion which has aggravated ecological problems. Accelerating soil degradation has led peasants to extend their lands under cultivation to the detriment of forest cover. Cattle herding remains the principal economic activity in the southwest. Herding has progressed from nomadism to pastoralism, but it remains a sign of power and wealth. Transhumance is the strategy of herders faced with shortages of water and pasturage, demographic pressure, and environmental degradation. Raising of sheep and goats constitutes a supplemental food source, medium of exchange, and form of savings. But angora goats graze on everything in their path, devastating their surrounds. Fear of cattle thefts militates against efforts to improve the quality of the stock. The various problems together have prompted a wasteful exploitation of the forest resources. Development strategies for the area explored by the government have all been forced to consider the high cost of potable water. A water project forms part of the Environmental Plan of Action launched by Madagascar with the assistance of international organizations. PMID:12286688

Razanamparany, L

1993-04-01

154

Molecular characterization of recombinant T1, a non-allergenic periwinkle (Catharanthus roseus) protein, with sequence similarity to the Bet v 1 plant allergen family.  

PubMed Central

More than 25% of the population suffer from Type I allergy, an IgE-mediated hypersensitivity disease. Allergens with homology to the major birch ( Betula verrucosa ) pollen allergen, Bet v 1, belong to the most potent elicitors of IgE-mediated allergies. T1, a cytokinin-inducible cytoplasmic periwinkle ( Catharanthus roseus ) protein, with significant sequence similarity to members of the Bet v 1 plant allergen family, was expressed in Escherichia coli. Recombinant T1 (rT1) did not react with IgE antibodies from allergic patients, and failed to induce basophil histamine release and immediate-type skin reactions in Bet v 1-allergic patients. Antibodies raised against purified rT1 could be used for in situ localization of natural T1 by immunogold electron microscopy, but did not cross-react with most of the Bet v 1-related allergens. CD analysis showed significant differences regarding secondary structure and thermal denaturation behaviour between rT1 and recombinant Bet v 1, suggesting that these structural differences are responsible for the different allergenicity of the proteins. T1 represents a non-allergenic member of the Bet v 1 family that may be used to study structural requirements of allergenicity and to engineer hypo-allergenic plants by replacing Bet v 1-related allergens for primary prevention of allergy. PMID:12656672

Laffer, Sylvia; Hamdi, Said; Lupinek, Christian; Sperr, Wolfgang R; Valent, Peter; Verdino, Petra; Keller, Walter; Grote, Monika; Hoffmann-Sommergruber, Karin; Scheiner, Otto; Kraft, Dietrich; Rideau, Marc; Valenta, Rudolf

2003-01-01

155

Identification of a 115kDa MAP-kinase activated by freezing and anoxic stresses in the marine periwinkle, Littorina littorea.  

PubMed

The mitogen-activated protein kinase (MAPK) cascade regulates changes in gene transcription by transmitting extracellular stimuli from the plasma membrane to the cell nucleus and has an important role to play in organismal responses to environmental stresses. The activities of MAPKs were investigated in the marine gastropod mollusk, Littorina littorea, a species that tolerates both extracellular freezing and long term oxygen deprivation. In-gel kinase assays revealed the presence of two MAPKs in foot muscle and hepatopancreas, a 42 and a 115kDa protein. Immunoblot analysis showed that both were MAPK proteins and that one was the periwinkle homologue of p42(ERK2). Size exclusion chromatography confirmed the 115kDa size of the novel snail MAPK and its role as the dominant MAPK activity in foot muscle. In-gel kinase assays, immunoblotting with phospho-specific ERK antibody, as well as kinase activity profiles from hydroxyapatite chromatography demonstrated that p115 MAPK kinase activity was increased in foot muscle in response to in vivo freezing or anoxia exposures. The results suggest a role for this novel kinase in environmental stress response. PMID:16620767

MacDonald, Justin A; Storey, Kenneth B

2006-06-15

156

Atelier paludisme: an international malaria training course held in Madagascar  

PubMed Central

The Atelier Paludisme (Malaria Workshop) is an international training course organized by the Institut Pasteur de Madagascar, which has been held annually for the past five years. The course was designed for both young and experienced researchers, as well as for healthcare professionals, mostly from malaria-endemic countries. Its objective is to provide participants with a broad knowledge of all features of malaria, to improve their skills in project management, to break geographical isolation by using the Internet as a source of documentary information. This six-week course makes use of concepts of andragogy and problem-based learning, i.e. a relationship between participants and tutors, which promotes a process of exchange rather than the simple transmission of knowledge, where participants have to search actively for information. This approach to training, combined with the wide background and experience of those involved, creates positive dynamics and enables participants to acquire new skills, develop their critical and analytical abilities. This paper describes the course and the lessons learned from its evaluation. PMID:18471291

Domarle, Olivier; Randrianarivelojosia, Milijaona; Duchemin, Jean-Bernard; Robert, Vincent; Ariey, Frederic

2008-01-01

157

Trans-oceanic and endemic origins of the small minnow mayflies (Ephemeroptera, Baetidae) of Madagascar  

PubMed Central

We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300?bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects. Ancestral state likelihood analysis suggested at least one Afrotropical lineage had its origin in Madagascar, demonstrating that unidirectional dispersal from a continental source may be too simplistic. We conclude that the Malagasy mayfly fauna should be considered in a biogeographical context that extends beyond Madagascar itself, encompassing trans-oceanic dispersal within multiple lineages. PMID:16096096

Monaghan, Michael T; Gattolliat, Jean-Luc; Sartori, Michel; Elouard, Jean-Marc; James, Helen; Derleth, Pascale; Glaizot, Olivier; de Moor, Ferdy; Vogler, Alfried P

2005-01-01

158

Timing of hot spot--related volcanism and the breakup of madagascar and India.  

PubMed

Widespread basalts and rhyolites were erupted in Madagascar during the Late Cretaceous. These are considered to be related to the Marion hot spot and the breakup of Madagascar and Greater India. Seventeen argon-40/argon-39 age determinations reveal that volcanic rocks and dikes from the 1500-kilometer-long rifted eastern margin of Madagascar were emplaced rapidly (mean age = 87.6 +/- 0.6 million years ago) and that the entire duration of Cretaceous volcanism on the island was no more than 6 million years. The evidence suggests that the thick lava pile at Volcan de l'Androy in the south of the island marks the focal point of the Marion hot spot at approximately 88 million years ago and that this mantle plume was instrumental in causing continental breakup. PMID:17813912

Storey, M; Mahoney, J J; Saunders, A D; Duncan, R A; Kelley, S P; Coffin, M F

1995-02-10

159

Early initiation of and exclusive breastfeeding in large-scale community-based programmes in Bolivia and Madagascar.  

PubMed

About one-fourth to one-half of all infant deaths in developing countries occur in the first week of life. Immediate breastfeeding within the first hour, followed by early exclusive breastfeeding, improves the health and survival status of newborns. The aim of this study was to demonstrate that breastfeeding practices, crucial to infant health, can be improved at scale in developing countries. During 1999-2003, the LINKAGES Project, funded by the United States Agency for International Development, implemented its community-based model to bring about rapid change in individual behaviours and community norms regarding early and exclusive breastfeeding, at a scale [LINKAGES' definition of 'scale' was adapted from a CORE Group background paper on 'Scaling-up' maternal, newborn, and child health services, 11 July 2005] that could achieve significant public-health impact. 'Scale' was defined as bringing improved infant-feeding practices to more people over a wider geographic area, more quickly, more equitably, and with sustainability as a goal. During this time, country-specific programmes were designed and implemented in Bolivia and Madagascar, with catchment populations of one million and six million respectively. These country programmes were implemented with multiple local government, private voluntary organizations, and partners of non-governmental organizations (NGOs) through existing health and nutrition activities. Breastfeeding was an entry point to work at all levels of the healthcare system and, within communities, using policy/advocacy and training for healthcare workers, with a particular emphasis on front-line health workers and community members. Harmonized messages and materials, including mass media, were developed and used by partners. Timely initiation of breastfeeding was one indicator measured. Data collected through rapid assessment surveys showed statistically significant increases (p<0.001) in timely initiation of breastfeeding in both the countries. In Bolivia, timely initiation of breastfeeding went from 56% in 2000 to 69% in 2001 and reached 74% by the end of 2003. In Madagascar, the initiation rate went from 34% at baseline in 2000 to 69% in 2001, 76% in 2002, and rose to 78% in 2004. Exclusive breastfeeding during the first month of life was also measured. At baseline in Bolivia, the rate of exclusive breastfeeding for the first month of life was 81% (2000), decreased slightly in 2001, and then increased to 88% by the end of the Project in 2003. In Madagascar, it started high at 86% in 2000, increased during the implementation of the programme, and by 2004, was 91%. These results were achieved quickly and sustained over the course of the intervention. PMID:17591350

Baker, Elizabeth Jean; Sanei, Linda C; Franklin, Nadra

2006-12-01

160

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle  

USGS Publications Warehouse

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. ?? 2008 The Authors.

Johnson, J.A.; Tingay, R.E.; Culver, M.; Hailer, F.; Clarke, M.L.; Mindell, D.P.

2009-01-01

161

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle.  

PubMed

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. PMID:19140964

Johnson, Jeff A; Tingay, Ruth E; Culver, Melanie; Hailer, Frank; Clarke, Michèle L; Mindell, David P

2009-01-01

162

An Unexpected Recurrent Transmission of Rift Valley Fever Virus in Cattle in a Temperate and Mountainous Area of Madagascar  

PubMed Central

Rift Valley fever is an acute, zoonotic viral disease of domestic ruminants, caused by a phlebovirus (Bunyaviridae family). A large outbreak occurred in Madagascar in 2008–2009. The goal of the present study was to evaluate the point prevalence of antibodies against Rift Valley Fever Virus (RVFV) in cattle in the Anjozorobe district, located in the wet and temperate highland region of Madagascar and yet heavily affected by the disease, and analyse environmental and trade factors potentially linked to RVFV transmission. A serological study was performed in 2009 in 894 bovines. For each bovine, the following variables were recorded: age, location of the night pen, minimum distance from the pen to the nearest water point and the forest, nearest water point type, and herd replacement practices. The serological data were analyzed using a generalized linear mixed model. The overall anti-RVFV IgG seroprevalence rate was 28% [CI95% 25–31]. Age was statistically linked to prevalence (p?=?10?4), being consistent with a recurrent RVFV circulation. Distance from the night pen to the nearest water point was a protective factor (p?=?5.10?3), which would be compatible with a substantial part of the virus transmission being carried out by nocturnal mosquito vectors. However, water point type did not influence the risk of infection: several mosquito species are probably involved. Cattle belonging to owners who purchase animals to renew the herd were significantly more likely to have seroconverted than others (p?=?0.04): cattle trade may contribute to the introduction of the virus in this area. The minimum distance of the night pen to the forest was not linked to the prevalence. This is the first evidence of a recurrent transmission of RVFV in such an ecosystem that associates a wet, temperate climate, high altitude, paddy fields, and vicinity to a dense rain forest. Persistence mechanisms need to be further investigated. PMID:22206026

Chevalier, Veronique; Rakotondrafara, Toky; Jourdan, Marion; Heraud, Jean Michel; Andriamanivo, Harena Rasamoelina; Durand, Benoit; Ravaomanana, Julie; Rollin, Pierre E.; Rakotondravao, Rene

2011-01-01

163

Human and environmental controls over aboveground carbon storage in Madagascar  

PubMed Central

Background Accurate, high-resolution mapping of aboveground carbon density (ACD, Mg C ha-1) could provide insight into human and environmental controls over ecosystem state and functioning, and could support conservation and climate policy development. However, mapping ACD has proven challenging, particularly in spatially complex regions harboring a mosaic of land use activities, or in remote montane areas that are difficult to access and poorly understood ecologically. Using a combination of field measurements, airborne Light Detection and Ranging (LiDAR) and satellite data, we present the first large-scale, high-resolution estimates of aboveground carbon stocks in Madagascar. Results We found that elevation and the fraction of photosynthetic vegetation (PV) cover, analyzed throughout forests of widely varying structure and condition, account for 27-67% of the spatial variation in ACD. This finding facilitated spatial extrapolation of LiDAR-based carbon estimates to a total of 2,372,680 ha using satellite data. Remote, humid sub-montane forests harbored the highest carbon densities, while ACD was suppressed in dry spiny forests and in montane humid ecosystems, as well as in most lowland areas with heightened human activity. Independent of human activity, aboveground carbon stocks were subject to strong physiographic controls expressed through variation in tropical forest canopy structure measured using airborne LiDAR. Conclusions High-resolution mapping of carbon stocks is possible in remote regions, with or without human activity, and thus carbon monitoring can be brought to highly endangered Malagasy forests as a climate-change mitigation and biological conservation strategy. PMID:22289685

2012-01-01

164

Economic valuation of subsistence harvest of wildlife in Madagascar.  

PubMed

Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife's ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha(-1) · year(-1). Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people's food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. PMID:24405165

Golden, Christopher D; Bonds, Matthew H; Brashares, Justin S; Rasolofoniaina, B J Rodolph; Kremen, Claire

2014-02-01

165

Economic Valuation of Subsistence Harvest of Wildlife in Madagascar  

PubMed Central

Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife’s ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha?1 · year?1. Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people’s food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. PMID:24405165

Golden, Christopher D.; Bonds, Matthew H.; Brashares, Justin S.; Rasolofoniaina, B. J. Rodolph; Kremen, Claire

2014-01-01

166

PLEURONECTIDAE DE L'ILE DE LA RÉUNION? ET DE MADAGASCAR.? II. GENRES SAMARIS ET SAMARISCUS  

Microsoft Academic Search

Among specimens of 5amarinae (pleuronectidae) recently collected from the waters of Reunion Island and Madagascar are three species new to science (Samaris costae, Samariscus nie\\/seni and Samariscus desouJterae). Another species represented in the collections is an unidentifiable Samaris species. Keys to Indo-Pacific species of Samaris. Samariscus and P\\/agiopsetla are' presented.

1989-01-01

167

New discoveries of skeletal elements of Hadropithecus stenognathus from Andrahomana Cave, southeastern Madagascar  

Microsoft Academic Search

Remains of what appears to be a single, subadult Hadropithecus stenognathus were recovered from a previously unexcavated site at Andrahomana Cave (southeastern Madagascar). Specimens found comprise isolated teeth and cranial fragments (including the frontal processes of the orbits), as well as a partial postcranial skeleton. They include the first associated fore- and hind-limb bones, confirming the hind-limb attributions made by

L. R. Godfrey; W. L. Jungers; D. A. Burney; N. Vasey; Ramilisonina; W. Wheeler; P. Lemelin; L. J. Shapiro; G. T. Schwartz; S. J. King; M. F. Ramarolahy; L. L. Raharivony; G. F. N. Randria

2006-01-01

168

The distribution and conservation of bats in the dry regions of Madagascar  

Microsoft Academic Search

We carried out extensive field surveys in the dry forest portions of Madagascar to document the species of bats occurring in these regions. These data combined with information in the literature and museum specimen records indicate that 28 species of Chiroptera occur in this region of the island, of which we documented 27 during our inventories. The community composition at

Steven M. Goodman; Daudet Andriafidison; Radosoa Andrianaivoarivelo; Scott G. Cardiff; Edina Ifticene; Richard K. B. Jenkins; Amyot Kofoky; Tsibara Mbohoahy; Daniel Rakotondravony; Julie Razafimanahaka; Fanja Ratrimomanarivo; Paul A. Racey

2005-01-01

169

RESEARCH ARTICLE Positive effects of climate change on rice in Madagascar  

E-print Network

. The present article reports the impact of various climate changes on rice productivity in four croppingRESEARCH ARTICLE Positive effects of climate change on rice in Madagascar Edward Gerardeaux on rice yields are positive under the most pessimistic climate change scenarios but we demonstrate

Paris-Sud XI, Université de

170

Genetics of the Pig Tapeworm in Madagascar Reveal a History of Human Dispersal and Colonization  

PubMed Central

An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation. PMID:25329310

Yanagida, Tetsuya; Carod, Jean-Francois; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P.; Ito, Akira

2014-01-01

171

Permian to tertiary faunas and paleogeography: Somalia, Kenya Tanzania, Mozambique, Madagascar, South Africa  

Microsoft Academic Search

Permian to Tertiary faunas along the eastern margin of Africa, and on Madagascar, are presented, described, and discussed. Presentation of the faunas is made in four charts: Permo-Triassic, Jurassic, Cretaceous, and Tertiary. A correlation chart provides tentative time-rock units. Paleogeography northeast and east of Africa is derived from the writer's analysis of marine invertebrate fauna, and is delineated in sketches

Maurice Kamen-Kaye

1978-01-01

172

Schistosoma haematobium induced lesions in the female genital tract in a village in Madagascar  

Microsoft Academic Search

Female genital schistosomiasis, FGS, was investigated in a gynaecological study as part of an overall community based morbidity survey, including parasitological and ultrasonographical examination, of a Schistosoma haematobium endemic area in Madagascar. Women (103), of childbearing age (15–49 years), were included for a gynaecological examination and visible lesions of vagina and cervix were biopsied in order to determine the origin

P Leutscher; C Raharisolo; J. L Pecarrere; V. E Ravaoalimalala; J Serieye; M Rasendramino; B Vennervald; H Feldmeier; P Esterre

1997-01-01

173

Understanding Mortality and the Life of the Ancestors in Rural Madagascar  

ERIC Educational Resources Information Center

Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The…

Astuti, Rita; Harris, Paul L.

2008-01-01

174

Robustness of subjective welfare analysis in a poor developing country: Madagascar 2001  

Microsoft Academic Search

We analyse the subjective perceptions of poverty in Madagascar in 2001 and their relationship to objective poverty indicators. We base our analysis on survey responses to a series of subjective perception questions. We extend the existing empirical methodology for estimating subjective poverty lines on the basis of categorical consumption adequacy questions. Based on this methodology, we calculate the household-specific, subjective

Michael Lokshin; Nithin Umapathi; Stefano Paternostro

2006-01-01

175

Vetiver Victorious: The Systematic Use of Vetiver to Save Madagascar's FCE Railway  

Microsoft Academic Search

In 2000, two cyclones hit the island nation of Madagascar in a two-week period. The devastation to infrastructur es was enormous. Among the worst hit was the FCE train line in the southeastern part of the country that suffered more than 280 landslides. The line was closed for three months, causing severe hardship to the more than 100 000 people

Diti Hengchaovanich; Karen Schoonmaker Freudenberger

176

Long-term changes in dominance ranks among ring-tailed lemurs at Berenty Reserve, Madagascar  

Microsoft Academic Search

A study was conducted between 1989 and 2001 to monitor changes in the dominance ranks among adult ring-tailed lemurs (Lemur catta) at Berenty Reserve, Madagascar. Adult females were observed to be dominant over adult males. Their rank fluctuated greatly. However, in some troops, female rank orders were fairly stable over a period of several years. In general, male ranks were

Naoki Koyama; Shinichiro Ichino; Masayuki Nakamichi; Yukio Takahata

2005-01-01

177

Co-Circulation and Evolution of Polioviruses and Species C Enteroviruses in a District of Madagascar  

Microsoft Academic Search

Between October 2001 and April 2002, five cases of acute flaccid paralysis (AFP) associated with type 2 vaccine-derived polioviruses (VDPVs) were reported in the southern province of the Republic of Madagascar. To determine viral factors that favor the emergence of these pathogenic VDPVs, we analyzed in detail their genomic and phenotypic characteristics and compared them with co-circulating enteroviruses. These VDPVs

Mala Rakoto-Andrianarivelo; Sophie Guillot; Jane Iber; Jean Balanant; Bruno Blondel; Franck Riquet; Javier Martin; Olen Kew; Bakolalao Randriamanalina; Lalatiana Razafinimpiasa; Dominique Rousset; Francis Delpeyroux

2007-01-01

178

The osteology of Masiakasaurus knopfleri, a small abelisauroid (Dinosauria: Theropoda) from the Late Cretaceous of Madagascar  

Microsoft Academic Search

We describe the osteology of the new small theropod dinosaur Masiakasaurus knopfleri, from the Late Cretaceous Maevarano Formation of northwestern Madagascar. Approximately 40% of the skeleton is known, including parts of the jaws, axial column, forelimb, pelvic girdle, and hind limb. The jaws of Masiakasaurus are remarkably derived, bearing a heterodont, procumbent dentition that is unknown elsewhere among dinosaurs. The

Matthew T. Carrano; Scott D. Sampson; Catherine A. Forster

2002-01-01

179

Frugivory and Seed Dispersal by Four Species of Primates in Madagascar's Eastern Rain Forest1  

Microsoft Academic Search

In the unique faunal assemblage of the Malagasy rain forest, lemurs appear to play particularly important roles as seed-dispersing frugivores. A three-month study of feeding ecology and seed dispersal by four species of lemurs in Madagascar's eastern rain forest found that three species, Eulemur rubriventer, Eulemur fulvus, and Erecia variegata were seed dispersers, and the fourth, Propithecus diadema, was a

J. Lawrence Dew; Patricia Wright

1998-01-01

180

Les mandres du dveloppement agricole au Lac Alaotra, Madagascar Entre inconstance politique et innovation technique  

E-print Network

. This conflict of temporalities shaped an agricultural history which built itself more or less between East bank and integration to markets. Key words : agriculture, development, policy, innovation, Lac Alaotra, Madagascar L'histoire mouvementée de l'évolution de l'agriculture au Lac Alaotra, principal grenier à riz de

Paris-Sud XI, Université de

181

Les mandres du dveloppement agricole au Lac Alaotra, Madagascar Entre inconstance politique et innovation technique  

E-print Network

shaped an agricultural history which built itself more or less between East bank and West bank and integration to markets. Key words : agriculture, development, policy, innovation, Lac Alaotra, Madagascar / BV Lac Alaotra Résumé L'histoire mouvementée de l'évolution de l'agriculture au Lac Alaotra

Paris-Sud XI, Université de

182

Conservation, Development, and a Heterogeneous Community: The Case of Ambohitantely Special Reserve, Madagascar  

Microsoft Academic Search

At the Ambohitantely Special Reserve in the central highlands of Madagascar, local people's use of fire and conservation authorities' efforts to change local practice illustrate the complexity of conservation issues. In theory the integrated conservation and development discourse provides a people-oriented context for framing conservation strategies, but in practice it may be no more effective than the “fortress”-style approach that

Jørgen Klein; Bertrand Réau; Ingvild Kalland; Mary Edwards

2007-01-01

183

Romancing Dahalo: The Social Environment of Cattle Theft in Ihorombe, Madagascar  

Microsoft Academic Search

In 1990 a woman named Nancy, a Peace Corps worker in southern Madagascar, received a marriage proposal from a man she did not know. It was Easter Monday, a national holiday for the Malagasy, and the man had been drinking; his proposal included a dowry of a very substantial number of cattle, an animal of tremendous cultural and material wealth

John McNair

2008-01-01

184

The genetic population structure of the gray mouse lemur ( Microcebus murinus), a basal primate from Madagascar  

Microsoft Academic Search

The genetic structure of a population is closely connected to fundamental evolutionary processes and aspects of social behavior. Information on genetic structure is therefore instrumental for the interpretation of social behavior and evolutionary reconstructions of social systems. Gray mouse lemurs (Microcebus murinus) are basal primates endemic to Madagascar whose social organization is characterized by solitary foraging at night and communal

Barbara Wimmer; Diethard Tautz; Peter M. Kappeler

2002-01-01

185

Epidemiologic Features of Four Successive Annual Outbreaks of Bubonic Plague in Mahajanga, Madagascar  

Microsoft Academic Search

From 1995 to 1998, outbreaks of bubonic plague occurred annually in the coastal city of Mahajanga, Madagascar. A total of 1,702 clinically suspected cases of bubonic plague were reported, including 515 laboratory confirmed by Yersinia pestis isolation (297), enzyme-linked immunosorbent assay, or both. Incidence was higher in males and young persons. Most buboes were inguinal, but children had a higher

Pascal Boisier; Lila Rahalison; Monique Rasolomaharo; Maherisoa Ratsitorahina; Mahafaly Mahafaly; Maminiriana Razafimahefa; Jean-Marc Duplantier; Lala Ratsifasoamanana; Suzanne Chanteau

2002-01-01

186

Madagascar corals reveal a multidecadal signature of rainfall and river runoff since 1708  

NASA Astrophysics Data System (ADS)

Pacific Ocean sea surface temperatures (SST) influence rainfall variability on multidecadal and interdecadal timescales in concert with the Pacific Decadal Oscillation (PDO) and Interdecadal Pacific Oscillation (IPO). Rainfall variations in locations such as Australia and North America are therefore linked to phase changes in the PDO. Furthermore, studies have suggested teleconnections exist between the western Indian Ocean and Pacific Decadal Variability (PDV), similar to those observed on interannual timescales related to the El Niño Southern Oscillation (ENSO). However, as instrumental records of rainfall are too short and sparse to confidently assess multidecadal climatic teleconnections, here we present four coral climate archives from Madagascar spanning up to the past 300 yr (1708-2008) to assess such decadal variability. Using spectral luminescence scanning to reconstruct past changes in river runoff, we identify significant multidecadal and interdecadal frequencies in the coral records, which before 1900 are coherent with Asian-based PDO reconstructions. This multidecadal relationship with the Asian-based PDO reconstructions points to an unidentified teleconnection mechanism that affects Madagascar rainfall/runoff, most likely triggered by multidecadal changes in North Pacific SST, influencing the Asian Monsoon circulation. In the 20th century we decouple human deforestation effects from rainfall-induced soil erosion by pairing luminescence with coral geochemistry. Positive PDO phases are associated with increased Indian Ocean temperatures and runoff/rainfall in eastern Madagascar, while precipitation in southern Africa and eastern Australia declines. Consequently, the negative PDO phase that started in 1998 may contribute to reduced rainfall over eastern Madagascar and increased precipitation in southern Africa and eastern Australia. We conclude that multidecadal rainfall variability in Madagascar and the western Indian Ocean needs to be taken into account when considering water resource management under a future warming climate.

Grove, C. A.; Zinke, J.; Peeters, F.; Park, W.; Scheufen, T.; Kasper, S.; Randriamanantsoa, B.; McCulloch, M. T.; Brummer, G.-J. A.

2013-03-01

187

Temporal and Spatial Evolution of Dynamic Support From River Profiles: A Framework for Madagascar and Africa  

NASA Astrophysics Data System (ADS)

It is generally accepted that the surface topography of Africa is a manifestation of convective circulation in the sub-lithospheric mantle. Here, we present an inverse method whereby longitudinal river profiles are interrogated to extract quantitative estimates of spatial and temporal variations in the rate of tectonic uplift. Surface processes can provide an important window into transient convective circulation in the sub-lithospheric mantle. River profiles act as 'tectonic tape recorders': we assume the generation of broad, convex-upward knickzones to represent the effect of tectonic uplift shifting the river system into a state of disequilibrium. Profiles evolve through time primarily via the headward retreat of these knickzones. We use a conjugate gradient inverse algorithm to minimise the misfit between observed river profiles - derived from a regional Digital Elevation Model (DEM) - and calculated profiles obtained by varying the uplift rate history. We jointly invert a total of 98 Malagasy and 570 African river profiles to obtain a history of the cumulative tectonic uplift through geological time. We show that Africa has undergone two phases of rapid uplift: first in Eocene times; secondly, since 10 Ma. While the first gave rise to broad, long wavelength topography, the second led to more localised domal swells of high relief. We propose the existence of two wavelengths of dynamic support, reflecting a change in the style of convection in the upper mantle since 50 Ma. Our results correlate strongly with independent geological estimates of uplift across Africa and Madagascar, while our calculated landscape surface following 50 Myr of uplift corresponds closely to a surface fit across present-day drainage divides. Finally we calculate the solid sediment flux delivered to major African deltas as a function of time. This onshore record provides an important indirect constraint on the history of vertical motions at the surface, and agrees well with the offshore flux record, obtained from mapping the thickness of chronostratigraphic sediment packages at the deltas.

Paul, J. D.; Roberts, G. G.; White, N.

2012-04-01

188

Geological evolution of the Antongil Craton, NE Madagascar  

USGS Publications Warehouse

The Antongil Craton, along with the Masora and Antananarivo cratons, make up the fundamental Archaean building blocks of the island of Madagascar. They were juxtaposed during the late-Neoproterozoic to early Palaeozoic assembly of Gondwana. In this paper we give a synthesis of the geology of the Antongil Craton and present previously published and new geochemical and U-Pb zircon analyses to provide an event history for its evolution.The oldest rocks in the Antongil Craton form a nucleus of tonalitic gneiss, characteristic of Palaeo-Mesoarchaean cratons globally, including phases dated between 3320 ?? 14. Ma to 3231 ?? 6. Ma and 3187 ?? 2. Ma to 3154 ?? 5. Ma. A series of mafic dykes was intruded into the Mesoarchaean tonalites and a sedimentary succession was deposited on the craton prior to pervasive deformation and migmatisation of the region. The age of deposition of the metasediments has been constrained from a volcanic horizon to around 3178 ?? 2. Ma and subject to migmatisation at around 2597 ?? 49. Ma. A subsequent magmatic episode generated voluminous, weakly foliated granitic rocks, that also included additions from both reworked older crustal material and younger source components. An earlier granodiorite-dominated assemblage, dated between 2570 ?? 18. Ma and 2542 ?? 5. Ma, is largely exposed in xenoliths and more continuously in the northern part of the craton, while a later monzogranite-dominated phase, dated between 2531 ?? 13. Ma and 2513 ?? 0.4. Ma is more widely developed. Together these record the stabilisation of the craton, attested to by the intrusion of a younger dyke swarm, the age of which is constrained by a sample of metagabbro dated at 2147 ?? 6. Ma, providing the first evidence for Palaeoproterozoic rocks from the Antongil Craton.The youngest events recorded in the isotopic record of the Antongil Craton are reflected in metamorphism, neocrystallisation and Pb-loss at 792 ?? 130. Ma to 763 ?? 13. Ma and 553 ?? 68. Ma. These events are interpreted as being the only manifestation of the Pan-African orogeny seen in the craton, which led to the assembly of the tectonic blocks that comprise the island. ?? 2010 NERC.

Schofield, D. I.; Thomas, R. J.; Goodenough, K. M.; De Waele, B.; Pitfield, P. E. J.; Key, R. M.; Bauer, W.; Walsh, G. J.; Lidke, D. J.; Ralison, A. V.; Rabarimanana, M.; Rafahatelo, J. M.; Randriamananjara, T.

2010-01-01

189

The lemurs of marojejy strict nature reserve, Madagascar: A status overview with notes on ecology and threats  

Microsoft Academic Search

From mid-August to late October 1988, we surveyed Marojejy Strict Nature Reserve, in the northern part of Madagascar’s rain\\u000a forest. Although widely believed to be a keystone site for lemur conservation, only incidental information concerning Marojejy’s\\u000a primate communities has hitherto been published. The reserve extends from 75 to 2133 m in altitude, and its 60,150 ha comprise\\u000a an almost-intact series

J. W. Duckworth; M. I. Evans; A. F. A. Hawkins; R. J. Safford; R. J. Wilkinson

1995-01-01

190

Rainforest Pharmacopeia in Madagascar Provides High Value for Current Local and Prospective Global Uses  

PubMed Central

Botanical diversity provides value to humans through carbon sequestration, air and water purification, and the provisioning of wild foods and ethnomedicines. Here we calculate the value of botanical ethnomedicines in a rainforest region of Madagascar, the Makira Protected Area, using a substitution method that combines replacement costs and choice modeling. The Makira watershed may comprise approximately 0.8% of global botanical diversity and possesses enormous value both in its ability to provision botanical ethnomedicines to local people and as a source of potentially novel pharmaceutical drugs for society as a whole. Approximately 241 locally-recognized species are used as ethnomedicines, including 113 agricultural or weed species. We equated each ethnomedicinal treatment to the monetary value of a comparable pharmaceutical treatment adjusted by personal preferences in perceived efficacy (rather than from known or assumed medicinal equivalency). The benefit value of these botanical ethnomedicines per individual is $5.40–7.90 per year when using the value of highly subsidized Malagasy pharmaceuticals and $100.60–287.40 when using the value of American pharmaceuticals. Using local pharmaceuticals as substitutes, the value per household is $30.24–44.30 per year, equivalent to 43–63% of median annual household income, demonstrating their local importance. Using the value of American pharmaceuticals, the amount is equivalent to 22–63% of the median annual health care expenditures for American adults under 45 in 2006. The potential for developing novel biomedicines from the Makira watershed’s unique flora ranges in untapped benefit value from $0.3–5.7 billion for American pharmaceutical companies, non-inclusive of the importance of providing novel medicines and improved healthcare to society. This study provides evidence of the tremendous current local and prospective global value of botanical ethnomedicines and furthers arguments for the conservation of tropical forests for sustainable use. Botanique de la diversité apporte de la valeur à l’homme par la séquestration du carbone, de l’air et de purification de l’eau, et le provisionnement des aliments sauvages et ethnomedicines. Ici, nous calculons la valeur de ethnomedicines botaniques dans une région de forêt de Madagascar, la zone protégée de Makira, en utilisant une méthode de substitution qui combine les coûts de remplacement et la modélisation des choix. Le bassin versant de Makira peut comprendre environ 0,8% de la diversité botanique mondiale et possède une valeur énorme à la fois dans sa capacité à fournir ethnomedicines botaniques à la population locale et en tant que source de nouveaux médicaments potentiellement pharmaceutiques pour la société dans son ensemble. Environ 241 espèces localement reconnus sont utilisés comme ethnomedicines, y compris 113 espèces d’agricoles ou de mauvaises herbes. Nous assimilé chaque traitement ethnomédicales à la valeur monétaire d’un traitement comparable pharmaceutique ajusté en fonction des préférences personnelles en matière d’efficacité perçue (plutôt que de l’équivalence médicament connu ou supposé). La valeur de l’avantage de ces ethnomedicines botaniques par individu est de $5,40 à 7.90 par année lors de l’utilisation de la valeur des produits pharmaceutiques malgaches fortement subventionnés et de $100,60 à 287,40 lors de l’utilisation de la valeur des produits pharmaceutiques américains. Utilisation de produits pharmaceutiques locales comme des substituts, la valeur par ménage est de $30.24 à 44.30 par an, équivalent à 43–63% du revenu médian des ménages annuelle, ce qui démontre leur importance locale. Utilisation de la valeur des produits pharmaceutiques

Golden, Christopher D.; Rasolofoniaina, B. J. Rodolph; Anjaranirina, E. J. Gasta; Nicolas, Lilien; Ravaoliny, Laurent; Kremen, Claire

2012-01-01

191

Anti-Predator Strategies in a Diurnal Prosimian, the Ring-Tailed Lemur ( Lemur catta ), at the Beza Mahafaly Special Reserve, Madagascar  

Microsoft Academic Search

With the dramatic increase in research on Madagascar’s lemurs during the past few decades, it is now feasible to both document\\u000a anti-predator behavior and to test predictions regarding the effect of predation pressure on the behavioral ecology of lemurs.\\u000a In 1994 Goodman raised much interest by his suggestion that, in the absence of large, extant predators on Madagascar, anti-predator\\u000a behaviors

Lisa Gould; Michelle L. Sauther

192

Deforestation history of the eastern rain forests of Madagascar from satellite images  

SciTech Connect

Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain forest remained, representing only 50% of the 7.6 million hectares existing in 1950 and 34% of the estimated original extent (11.2 million hectares). Between 1950 and 1985, the rate of deforestation averaged 111,000 hectares per year. Deforestation was most rapid in areas with low topographic relief and high population density. If cutting of forests continues at the same pace, only forests on the steepest slopes will survive the next 35 years.

Green, G.M.; Sussman, R.W. (Washington Univ., St. Louis, MO (USA))

1990-04-13

193

Degrading uplands in the rainforest region of Madagascar: Fallow biomass, nutrient stocks, and soil nutrient availability  

Microsoft Academic Search

Soil fertility restoration depends on natural fallows in the slash-and-burn system of eastern Madagascar. In the Beforona-Vohidrazana\\u000a study zone, none of the fallow species are able to withstand the slashing, burning and cropping frequencies of 3–5 years.\\u000a Eventually soils are abandoned for agriculture. Along the degradation sequence, this study quantifies fallow biomass, nutrient\\u000a stocks and soil nutrient availability of four dominant

Erika Styger; Erick C. M. Fernandes; Harivelo M. Rakotondramasy; Eric Rajaobelinirina

2009-01-01

194

Neoproterozoic extension in the greater dharwar craton: A reevaluation of the "betsimisaraka suture" in madagascar  

USGS Publications Warehouse

The Precambrian shield of Madagascar is reevaluated with recently compiled geological data and new U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology. Two Archean domains are recognized: the eastern Antongil-Masora domain and the central Antananarivo domain, the latter with distinctive belts of metamafic gneiss and schist (Tsaratanana Complex). In the eastern domain, the period of early crust formation is extended to the Paleo-Mesoarchean (3.32-3.15 Ga) and a supracrustal sequence (Fenerivo Group), deposited at 3.18 Ga and metamorphosed at 2.55 Ga, is identified. In the central domain, a Neoarchean period of high-grade metamorphism and anatexis that affected both felsic (Betsiboka Suite) and mafic gneisses (Tsaratanana Complex) is documented. We propose, therefore, that the Antananarivo domain was amalgamated within the Greater Dharwar Craton (India + Madagascar) by a Neoarchean accretion event (2.55-2.48 Ga), involving emplacement of juvenile igneous rocks, high-grade metamorphism, and the juxtaposition of disparate belts of mafic gneiss and schist (metagreenstones). The concept of the "Betsimisaraka suture" is dispelled and the zone is redefined as a domain of Neoproterozoic metasedimentary (Manampotsy Group) and metaigneous rocks (Itsindro-Imorona Suite) formed during a period of continental extension and intrusive igneous activity between 840 and 760 Ma. Younger orogenic convergence (560-520 Ma) resulted in east-directed overthrusting throughout south Madagascar and steepening with local inversion of the domain in central Madagascar. Along part of its length, the Manampotsy Group covers the boundary between the eastern and central Archean domains and is overprinted by the Angavo-Ifanadiana high-strain zone that served as a zone of crustal weakness throughout Cretaceous to Recent times.

Tucker, R. D.; Roig, J. -Y.; Delor, C.; Amlin, Y.; Goncalves, P.; Rabarimanana, M. H.; Ralison, A. V.; Belcher, R. W.

2011-01-01

195

Cycles of Activity, Group Composition, and Diet of Lemur mongoz mongoz Linnaeus 1766 in Madagascar  

Microsoft Academic Search

A preliminary study of the ecology and behavior of Lemur mongoz mongoz was carried out in the northwest of Madagascar. The animals were observed for approximately 250 h in July till August, 1973, and for 50 h in June, 1974. L.m.mongoz has been reported to be diurnal and to live in groups of 6–8 individuals. However, we found the animals

Robert W. Sussman; Ian Tattersall

1976-01-01

196

Aye-aye population genomic analyses highlight an important center of endemism in northern Madagascar  

PubMed Central

We performed a population genomics study of the aye-aye, a highly specialized nocturnal lemur from Madagascar. Aye-ayes have low population densities and extensive range requirements that could make this flagship species particularly susceptible to extinction. Therefore, knowledge of genetic diversity and differentiation among aye-aye populations is critical for conservation planning. Such information may also advance our general understanding of Malagasy biogeography, as aye-ayes have the largest species distribution of any lemur. We generated and analyzed whole-genome sequence data for 12 aye-ayes from three regions of Madagascar (North, West, and East). We found that the North population is genetically distinct, with strong differentiation from other aye-ayes over relatively short geographic distances. For comparison, the average FST value between the North and East aye-aye populations—separated by only 248 km—is over 2.1-times greater than that observed between human Africans and Europeans. This finding is consistent with prior watershed- and climate-based hypotheses of a center of endemism in northern Madagascar. Taken together, these results suggest a strong and long-term biogeographical barrier to gene flow. Thus, the specific attention that should be directed toward preserving large, contiguous aye-aye habitats in northern Madagascar may also benefit the conservation of other distinct taxonomic units. To help facilitate future ecological- and conservation-motivated population genomic analyses by noncomputational biologists, the analytical toolkit used in this study is available on the Galaxy Web site. PMID:23530231

Perry, George H.; Louis, Edward E.; Ratan, Aakrosh; Bedoya-Reina, Oscar C.; Burhans, Richard C.; Lei, Runhua; Johnson, Steig E.; Schuster, Stephan C.; Miller, Webb

2013-01-01

197

Daily torpor in the gray mouse lemur ( Microcebus murinus ) in Madagascar: energetic consequences and biological significance  

Microsoft Academic Search

Patterns and energetic consequences of spontaneous daily torpor were measured in the gray mouse lemur (Microcebus murinus) under natural conditions of ambient temperature and photoperiod in a dry deciduous forest in western Madagascar. Over a\\u000a period of two consecutive dry seasons, oxygen consumption (VO2) and body temperature (T\\u000a b) were measured on ten individuals kept in outdoor enclosures. In all

Jutta Schmid

2000-01-01

198

Habitat use, roost selection and conservation of bats in Tsingy de Bemaraha National Park, Madagascar  

Microsoft Academic Search

Although the land mammals of Madagascar have been the subject of many studies, the island’s bats have yet to feature prominently\\u000a on the research or conservation agenda. In this study we used mist nets, acoustic sampling and cave surveys to assess habitat\\u000a use, seasonality and roost selection. Four microchiropteran species (Triaenops rufus, T. furculus, Miniopterus manavi and Myotis goudoti) appeared

Amyot Kofoky; Daudet Andriafidison; Fanja Ratrimomanarivo; H. Julie Razafimanahaka; Daniel Rakotondravony; Paul A. Racey; Richard K. B. Jenkins

199

Habitat Use, Roost Selection and Conservation of Bats in Tsingy De Bemaraha National Park, Madagascar  

Microsoft Academic Search

Although the land mammals of Madagascar have been the subject of many studies, the island’s bats have yet to feature prominently\\u000a on the research or conservation agenda. In this study we used mist nets, acoustic sampling and cave surveys to assess habitat\\u000a use, seasonality and roost selection. Four microchiropteran species (Triaenops rufus, T. furculus, Miniopterus manavi and Myotis goudoti) appeared

Amyot Kofoky; Daudet Andriafidison; Fanja Ratrimomanarivo; H. Julie Razafimanahaka; Daniel Rakotondravony; Paul A. Racey; Richard K. B. Jenkins

2007-01-01

200

A ten-year summary of reproductive parameters for ring-tailed lemurs at berenty, madagascar  

Microsoft Academic Search

From 1989 to 1998, 204 live births were recorded for ring-tailed lemurs (Lemur catta) at Berenty, Madagascar. Excluding unknown birth dates, the peak month of birth was September, with 82.0% (146\\/178) occurring\\u000a during this period. The offspring sex ratio (1?1.19) was not significantly different from 1?1, and there was no association\\u000a with the mother's age. The first births occurred at

Naoki Koyama; Masayuki Nakamichi; Ryo Oda; Naomi Miyamoto; Shinichiro Ichino; Yukio Takahata

2001-01-01

201

Mating behavior of ring-tailed lemurs ( Lemur catta ) at Berenty, Madagascar  

Microsoft Academic Search

The mating behavior of ring-tailed lemurs at Berenty, Madagascar, was observed in April 1982. Although Troop A included five\\u000a adult females, only two were observed to mate. The mating period covered two consecutive days, April 24 and 25. Each female\\u000a was receptive for about 4 hr. Data from 47 copulations, of which 38 were with ejaculation, suggest that to be

Naoki Koyama

1988-01-01

202

Daytime deliveries observed for the ring-tailed lemurs of the berenty reserve, Madagascar  

Microsoft Academic Search

In the Berenty Reserve, Southern Madagascar, of the 16 deliveries recorded for ring-tailed lemurs from 1995 and 1997, 10 cases\\u000a occurred during daytime hours (07:00 – 16:59). Four mothers lost contact with their troop members during parturition, but\\u000a were able to rejoin them after about one hour. No attack from the individuals of the neighboring groups or predators on the

Yukio Takahata; Naoki Koyama; Naomi Miyamoto; Megumi Okamoto

2001-01-01

203

Antipredator behavior in lemurs: Evidence of an extinct eagle on Madagascar or something else?  

Microsoft Academic Search

Goodman (1994) related the antipredator response exhibited by two species of lemurs from southwestern Madagascar against extant\\u000a birds of prey to the predatory efforts of an extinct eagle, inhabiting the same region about 4000 years ago. He argued that\\u000a today’s smaller raptors, hunting young individuals perhaps only occasionally, represent marginal danger to lemurs. Nevertheless,their activity would be sufficient to impose

Davide Csermely

1996-01-01

204

Economic Crisis and Changes in Mortality Due to Infectious and Parasitic Diseases in Antananarivo, Madagascar  

Microsoft Academic Search

Madagascar was severely affected by the economic crisis that hit sub-Saharan Africa in the 1980s. The crisis, exacerbated\\u000a by a high degree of political instability, led to food shortages in the mid-1980s. The impact on mortality is not well known,\\u000a owing to a lack of statistics for the whole island. Systematic analysis of the registers of the Municipal Hygiene Office

Dominique Waltisperger

205

The impact of advective transport by the South Indian Ocean Countercurrent on the Madagascar plankton bloom  

E-print Network

plankton bloom F. Huhn,1,2 A. von Kameke,1,3 V. P�rez-Mu�uzuri,1,4 M. J. Olascoaga,2 and F. J. Beron-Vera2�2007) of satellite ocean color data we analyze the spatiotemporal patterns in the seasonal Madagascar plankton bloom upwelling region, and extends to the east further than the largest plankton blooms ($2500 km). In bloom

Olascoaga, Maria Josefina

206

Susceptibility to Yersinia pestis Experimental Infection in Wild Rattus rattus , Reservoir of Plague in Madagascar  

Microsoft Academic Search

In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague\\u000a challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between

C. Tollenaere; L. Rahalison; M. Ranjalahy; J.-M. Duplantier; S. Rahelinirina; S. Telfer; C. Brouat

2010-01-01

207

CCR5 polymorphism and plague resistance in natural populations of the black rat in Madagascar  

Microsoft Academic Search

Madagascar remains one of the world's largest plague foci. The black rat, Rattus rattus, is the main reservoir of plague in rural areas. This species is highly susceptible to plague in plague-free areas (low-altitude regions), whereas rats from the plague focus areas (central highlands) have evolved a disease-resistance polymorphism. We used the candidate gene CCR5 to investigate the genetic basis

C. Tollenaere; L. Rahalison; M. Ranjalahy; S. Rahelinirina; J.-M. Duplantier; C. Brouat

2008-01-01

208

First Full Genome Sequence of a Human Enterovirus A120, Isolated in Madagascar  

PubMed Central

We report the first complete genome sequence of an enterovirus isolate belonging to the human enterovirus A species of the Picornaviridae family and to type A120 (EV-A120). The EV-A120 isolate MAD-2741-11 was obtained from the stool of a healthy child living on Madagascar Island. The isolate genome was amplified by a reverse transcription-PCR method, and the consensus sequence was determined. PMID:24948760

Joffret, Marie-Line; Delpeyroux, Francis; Heraud, Jean-Michel

2014-01-01

209

Diversification of an emerging pathogen in a biodiversity hotspot: Leptospira in endemic small mammals of Madagascar.  

PubMed

Biodiversity hotspots and associated endemism are ideal systems for the study of parasite diversity within host communities. Here, we investigated the ecological and evolutionary forces acting on the diversification of an emerging bacterial pathogen, Leptospira spp., in communities of endemic Malagasy small mammals. We determined the infection rate with pathogenic Leptospira in 20 species of sympatric rodents (subfamily Nesomyinae) and tenrecids (family Tenrecidae) at two eastern humid forest localities. A multilocus genotyping analysis allowed the characterization of bacterial diversity within small mammals and gave insights into their genetic relationships with Leptospira infecting endemic Malagasy bats (family Miniopteridae and Vespertilionidae). We report for the first time the presence of pathogenic Leptospira in Malagasy endemic small mammals, with an overall prevalence of 13%. In addition, these hosts harbour species of Leptospira (L. kirschneri, L. borgpetersenii and L. borgpetersenii group B) which are different from those reported in introduced rats (L. interrogans) on Madagascar. The diversification of Leptospira on Madagascar can be traced millions of years into evolutionary history, resulting in the divergence of endemic lineages and strong host specificity. These observations are discussed in relation to the relative roles of endemic vs. introduced mammal species in the evolution and epidemiology of Leptospira on Madagascar, specifically how biodiversity and biogeographical processes can shape community ecology of an emerging pathogen and lead to its diversification within native animal communities. PMID:24784171

Dietrich, Muriel; Wilkinson, David A; Soarimalala, Voahangy; Goodman, Steven M; Dellagi, Koussay; Tortosa, Pablo

2014-06-01

210

Biodiversity conservation and drug discovery: Can they be combined? The Suriname and Madagascar experiences  

PubMed Central

The approach to new drugs through natural products has proved to be the single most successful strategy for the discovery of new drugs, but in recent years its use has been deemphasized by many pharmaceutical companies in favor of approaches based on combinatorial chemistry and genomics, among others. Drug discovery from natural sources requires continued access to plant, marine, and microbial biomass, and so the preservation of tropical rainforests is an important part of our drug discovery program. Sadly, many of the tropical forests of the world are under severe environmental pressure, and deforestation is a serious problem in most tropical countries. One way to combat this loss is to demonstrate their value as potential sources of new pharmaceutical or agrochemical products. As part of an effort to integrate biodiversity conservation and drug discovery with economic development, we initiated an International Cooperative biodiversity Group (ICBG) to discover potential pharmaceuticals from the plant biodiversity of Suriname and Madagascar. The Group, established with funding from agencies of the United States government, involved participants from the USA, Suriname, and Madagascar. The basic approach was to search for bioactive plants in the Suriname and Malagasy flora, and to isolate their bioactive constituents by the best available methods, but the work included capacity building as well as research. Progress on this project will be reported, drawing on results obtained from the isolation of bioactive natural products from Suriname and Madagascar. The benefits of this general approach to biodiversity and drug discovery will also be discussed. PMID:20161050

Cao, Shugeng; Kingston, David G. I.

2009-01-01

211

Conservation education in Madagascar: three case studies in the biologically diverse island-continent.  

PubMed

Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island-continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascar's geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10-15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher-training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long-term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university. PMID:20039330

Dolins, Francine L; Jolly, Alison; Rasamimanana, Hantanirina; Ratsimbazafy, Jonah; Feistner, Anna T C; Ravoavy, Florent

2010-05-01

212

The Hippoboscidae (Insecta: Diptera) from Madagascar, with new records from the “Parc National de Midongy Befotaka”  

PubMed Central

The Hippoboscidae or “louse-flies” is a family of pupiparous Diptera, which in their adult stage are ectoparasites of mammals and birds. This paper presents a comprehensive review of Malagasy Hippoboscidae. In total, amongst the 213 species of this family known worldwide, 14 have been reported in Madagascar, among which six are considered as endemic to the Malagasy region. In addition, data are presented from a collection of 17 Hippoboscidae obtained from seven species of forest-dwelling birds in the “Parc National de Midongy Befotaka”, southeastern Madagascar, in 2003. The flies in this collection belong to three different species: Icosta malagasii (one), Ornithoica podicipis (ten) and Ornithoctona laticornis (six). The two former species were previously only known from single specimens in museum collections; the later species is distributed across much of the Afrotropical region and the records presented herein are the first for Madagascar. All the seven bird species are new hosts for hippoboscids. We present the first description of the male of Icosta malagasii. An illustrated dichotomous determination key of the 14 Malagasy species, based on morphological criteria only, is presented. PMID:21678788

Rahola, N.; Goodman, S.M.; Robert, V.

2011-01-01

213

The re-stocking of captive-bred ruffed lemurs (Varecia variegata variegata) into the Betampona Reserve, Madagascar: methodology and recommendations  

Microsoft Academic Search

Since November 1997 the Madagascar Fauna Group has released 13 captive-bred black and white ruffed lemurs (Varecia variegata variegata) into the Betampona Reserve in eastern Madagascar. The release programme has three major aims: (1) to assess the ability of captive-bred V. v. variegata to adapt to life in their natural habitat; (2) to investigate the contribution that such a release

Adam Britt; Charles Welch; Andrea Katz; Bernard Iambana; Ingrid Porton; Randall Junge; Graham Crawford; Cathy Williams; David Haring

2004-01-01

214

Consuming sex: the association between modern goods, lifestyles and sexual behaviour among youth in Madagascar  

PubMed Central

Background Ethnographic evidence suggests that transactional sex is sometimes motivated by youth’s interest in the consumption of modern goods as much as it is in basic survival. There are very few quantitative studies that examine the association between young people’s interests in the consumption of modern goods and their sexual behaviour. We examined this association in two regions and four residence zones of Madagascar: urban, peri-urban and rural Antananarivo, and urban Antsiranana. We expected risky sexual behaviour would be associated with interests in consuming modern goods or lifestyles; urban residence; and socio-cultural characteristics. Methods We administered a population-based survey to 2, 255 youth ages 15–24 in all four residence zones. Focus group discussions guided the survey instrument which assessed socio-demographic and economic characteristics, consumption of modern goods, preferred activities and sexual behaviour. Our outcomes measures included: multiple sexual partners in the last year (for men and women); and ever practicing transactional sex (for women). Results Overall, 7.3% of women and 30.7% of men reported having had multiple partners in the last year; and 5.9% of women reported ever practicing transactional sex. Bivariate results suggested that for both men and women having multiple partners was associated with perceptions concerning the importance of fashion and a series of activities associated with modern lifestyles. A subset of lifestyle characteristics remained significant in multivariate models. For transactional sex bivariate results suggested perceptions around fashion, nightclub attendance, and getting to know a foreigner were key determinants; and all remained significant in multivariate analysis. We found peri-urban residence more associated with transactional sex than urban residence; and ethnic origin was the strongest predictor of both outcomes for women. Conclusions While we found indication of an association between sexual behaviour and interest in modern goods, or modern lifestyles, such processes did not single-handedly explain risky sexual behaviour among youth; these behaviours were also shaped by culture and conditions of economic uncertainty. These determinants must all be accounted for when developing interventions to reduce risky transactional sex and vulnerability to HIV. PMID:23510104

2013-01-01

215

Isolation and structural elucidation of cytotoxic compounds from the root bark of Diospyros quercina (Baill.) endemic to Madagascar  

PubMed Central

Objective To isolate and characterize the cytotoxic compounds from Diospyros quercina (Baill.) G.E. Schatz & Lowry (Ebenaceae). Methods An ethno-botanical survey was conducted in the south of Madagascar from July to August 2010. Bio-guided fractionation assay was carried out on the root bark of Diospyros quercina, using cytotoxicity bioassay on murine P388 leukemia cell lines as model. The structures of the cytotoxic compounds were elucidated by 1D and 2D NMR spectroscopy and mass spectrometry. Results Biological experiments resulted in the isolation of three bioactive pure compounds (named TR-21, TR-22, and TR-23) which exhibited very good in vitro cytotoxic activities with the IC50 values of (0.017?5±0.0060) µg/mL, (0.089±0.005) µg/mL and (1.027±0.070) µg/mL respectively. Thus, they support the claims of traditional healers and suggest the possible correlation between the chemical composition of this plant and its wide use in Malagasy folk medicine to treat cancer. Conclusions The ability of isolated compounds in this study to inhibit cell growth may represent a rational explanation for the use of Diospyros quercina root bark in treating cancer by Malagasy traditional healers. Further studies are, therefore, necessary to evaluate the in vivo anti-neoplastic activity of these cytotoxic compounds as effective anticancer drugs. PMID:25182433

Ruphin, Fatiany Pierre; Baholy, Robijaona; Emmanuel, Randrianarivo; Amelie, Raharisololalao; Martin, Marie-Therese; Koto-te-Nyiwa, Ngbolua

2014-01-01

216

Deep phylogenetic divergence between Scolytoplatypus and Remansus, a new genus of Scolytoplatypodini from Madagascar (Coleoptera, Curculionidae, Scolytinae).  

PubMed

Scolytoplatypodini Blandford is a monotypic tribe of ambrosia beetles found in Asia, Madagascar and Africa. Only three species are currently known from Madagascar and four additional species are here described as new to science. Phylogenetic analyses of morphological and molecular data revealed that four of the seven endemic species are deeply separated from all other species by genetic and distinct morphological characters and therefore placed in a new genus Remansus Jordal. The split between this ancient lineage and Scolytoplatypus Schaufuss was estimated to approximate Palaeocene age (63 Ma), extending the minimum age of ambrosia feeding for this tribe to the beginning of the Palaeocene?Eocene thermal maximum (PETM). In addition to the ancient origin of Remansus in Madagascar during the Palaeocene, a second origin occurred in Scolytoplatypus no more than 13 Ma. A geographical origin of the latter in South-Eastern Africa was unequivocally inferred from the phylogenies. PMID:24294090

Jordal, Bjarte H

2013-01-01

217

an additional control variable in the synthesis of metal clusters. --MSL  

E-print Network

of complex metabo- lites important in plant defense. Leaves of the Madagascar periwinkle (Catharanthus roseus. have exploited RNA analysis of the leaf epidermis. C. roseus epider- mis is rich in a variety

Gotelli, Nicholas J.

218

Reprogramming alkaloid biosynthesis in Catharanthus roseus : synthetic biology in plants  

E-print Network

The medicinal plant Madagascar periwinkle (Catharanthus roseus) produces over 130 monoterpene indole alkaloid (MIA) natural products. Many of these compounds have pharmaceutical value, such as the anticancer agents vinblastine ...

Runguphan, Weerawat

2011-01-01

219

Small effect of fragmentation on the genetic diversity of Dalbergia monticola, an endangered tree species of the eastern forest of Madagascar, detected by chloroplast and nuclear microsatellites  

PubMed Central

Background and Aims The oriental forest ecosystem in Madagascar has been seriously impacted by fragmentation. The pattern of genetic diversity was analysed on a tree species, Dalbergia monticola, which plays an important economic role in Madagascar and is one of the many endangered tree species in the eastern forest. Methods Leaves from 546 individuals belonging to 18 small populations affected by different levels of fragmentation were genotyped using eight nuclear (nuc) and three chloroplast (cp) microsatellite markers. Key Results For nuclear microsatellites, allelic richness (R) and heterozygosity (He,nuc) differed between types of forest: R = 7·36 and R = 9·55, He,nuc = 0·64 and He,nuc = 0·80 in fragmented and non-fragmented forest, respectively, but the differences were not significant. Only the mean number of alleles (Na,nuc) and the fixation index FIS differed significantly: Na,nuc = 9·41 and Na,nuc = 13·18, FIS = 0·06 and FIS = 0·15 in fragmented and non-fragmented forests, respectively. For chloroplast microsatellites, estimated genetic diversity was higher in non-fragmented forest, but the difference was not significant. No recent bottleneck effect was detected for either population. Overall differentiation was low for nuclear microsatellites (FST,nuc = 0·08) and moderate for chloroplast microsatellites (FST,cp = 0·49). A clear relationship was observed between genetic and geographic distance (r = 0·42 P < 0·01 and r = 0·42 P = 0·03 for nuclear and chloroplast microsatellites, respectively), suggesting a pattern of isolation by distance. Analysis of population structure using the neighbor-joining method or Bayesian models separated southern populations from central and northern populations with nuclear microsatellites, and grouped the population according to regions with chloroplast microsatellites, but did not separate the fragmented populations. Conclusions Residual diversity and genetic structure of populations of D. monticola in Madagascar suggest a limited impact of fragmentation on molecular genetic parameters. PMID:19773273

Andrianoelina, O.; Favreau, B.; Ramamonjisoa, L.; Bouvet, J.-M.

2009-01-01

220

Noretta Koertge Department of History and Philosophy of Science  

E-print Network

that common medicines such as digitalis and ephedrine come from familiar plants. It goes on to describes new drugs for childhood leukemia and Hodgkin's disease that have been extracted from more esoteric plants, such as the Madagascar rosy periwinkle, and then concludes: Plants like the periwinkle have contributed

Koertge, Noretta

221

[Intestinal schistosomiasis from Schistosoma mansoni in Madagascar: extent and center of the endemic].  

PubMed

Schistosoma mansoni and S. haematobium affect respectively 2 million and 500,000 persons in Madagascar. Over the past decade, S. mansoni has spread in the central Highlands of Madagascar, essentially throughout the mid-west and Antananarivo plain. To understand this recent change in the epidemiology of S. mansoni, we examined the relationship between its spatial distribution and several host factors, including labour migration, urbanization and water development projects. In the Highlands, the disease in distribution could be superimposed on the potential expansion areas of snail distribution defined in 1958. However, the distribution is not homogeneous, as for example the road between Betafo and Mandoto (South West of Antananarivo). This focal pattern described in other African countries is unique to the central Highlands of Madagascar. Rice cultivation is the main economic activity and is associated with intense water contact. The focal distribution may be related to an environmental adaptation of host-parasite interaction depending on behavioural patterns, water and soil chemistry and incompatibility between Biomphalaria pfeifferi and S. mansoni. It is also possible that these focal patterns precede homogeneous endemicity, as along the road Itasy-Tsiroanomandidy (west Antananarivo). Major water development carried out in this migration area led to a rapid endemization of the disease. In Befato-Mandoto, where soil management is more restricted, schistosomiasis due to S. mansoni seems to have been established in some foci where epidemiologic conditions are favourable (for example, traditional irrigation canals). In contrast, the spread of S. mansoni in the Antananarivo plain closely follows the settlement of an infected rural population. Epidemiologic surveys conducted on school children in the Antananarivo suburbs, where sanitary conditions are poor, showed a prevalence of 25%. Human migration linked to development projects and urbanization seems to be the principal factor associated with the spread of schistosomiasis in the mid-west area and Antananarivo plain. In the Highlands, the preferential exposure of adult labour migrants has contributed to the widening of the endemic area. PMID:10399598

Ollivier, G; Brutus, L; Cot, M

1999-05-01

222

Analysis of Patterns of Bushmeat Consumption Reveals Extensive Exploitation of Protected Species in Eastern Madagascar  

PubMed Central

Understanding the patterns of wild meat consumption from tropical forests is important for designing approaches to address this major threat to biodiversity and mitigate potential pathways for transmission of emerging diseases. Bushmeat consumption has been particularly poorly studied in Madagascar, one of the world's hottest biodiversity hotspots. Studying bushmeat consumption is challenging as many species are protected and researchers must consider the incentives faced by informants. Using interviews with 1154 households in 12 communes in eastern Madagascar, as well as local monitoring data, we investigated the importance of socio-economic variables, taste preference and traditional taboos on consumption of 50 wild and domestic species. The majority of meals contain no animal protein. However, respondents consume a wide range of wild species and 95% of respondents have eaten at least one protected species (and nearly 45% have eaten more than 10). The rural/urban divide and wealth are important predictors of bushmeat consumption, but the magnitude and direction of the effect varies between species. Bushmeat species are not preferred and are considered inferior to fish and domestic animals. Taboos have provided protection to some species, particularly the Endangered Indri, but we present evidence that this taboo is rapidly eroding. By considering a variety of potential influences on consumption in a single study we have improved understanding of who is eating bushmeat and why. Evidence that bushmeat species are not generally preferred meats suggest that projects which increase the availability of domestic meat and fish may have success at reducing demand. We also suggest that enforcement of existing wildlife and firearm laws should be a priority, particularly in areas undergoing rapid social change. The issue of hunting as an important threat to biodiversity in Madagascar is only now being fully recognised. Urgent action is required to ensure that heavily hunted species are adequately protected. PMID:22194787

Jenkins, Richard K. B.; Keane, Aidan; Rakotoarivelo, Andrinajoro R.; Rakotomboavonjy, Victor; Randrianandrianina, Felicien H.; Razafimanahaka, H. Julie; Ralaiarimalala, Sylvain R.; Jones, Julia P. G.

2011-01-01

223

Convergent evolution of chemical defense in poison frogs and arthropod prey between Madagascar and the Neotropics  

PubMed Central

With few exceptions, aposematically colored poison frogs sequester defensive alkaloids, unchanged, from dietary arthropods. In the Neotropics, myrmicine and formicine ants and the siphonotid millipede Rhinotus purpureus are dietary sources for alkaloids in dendrobatid poison frogs, yet the arthropod sources for Mantella poison frogs in Madagascar remained unknown. We report GC-MS analyses of extracts of arthropods and microsympatric Malagasy poison frogs (Mantella) collected from Ranomafana, Madagascar. Arthropod sources for 11 “poison frog” alkaloids were discovered, 7 of which were also detected in microsympatric Mantella. These arthropod sources include three endemic Malagasy ants, Tetramorium electrum, Anochetus grandidieri, and Paratrechina amblyops (subfamilies Myrmicinae, Ponerinae, and Formicinae, respectively), and the pantropical tramp millipede R. purpureus. Two of these ant species, A. grandidieri and T. electrum, were also found in Mantella stomachs, and ants represented the dominant prey type (67.3% of 609 identified stomach arthropods). To our knowledge, detection of 5,8-disubstituted (ds) indolizidine iso-217B in T. electrum represents the first izidine having a branch point in its carbon skeleton to be identified from ants, and detection of 3,5-ds pyrrolizidine 251O in A. grandidieri represents the first ponerine ant proposed as a dietary source of poison frog alkaloids. Endemic Malagasy ants with defensive alkaloids (with the exception of Paratrechina) are not closely related to any Neotropical species sharing similar chemical defenses. Our results suggest convergent evolution for the acquisition of defensive alkaloids in these dietary ants, which may have been the critical prerequisite for subsequent convergence in poison frogs between Madagascar and the Neotropics. PMID:16087888

Clark, Valerie C.; Raxworthy, Christopher J.; Rakotomalala, Valerie; Sierwald, Petra; Fisher, Brian L.

2005-01-01

224

Medicinal plants used by women from Agnalazaha littoral forest (Southeastern Madagascar)  

PubMed Central

Background The country of Madagascar is renowned for its high level of biodiversity and endemism, as well as the overwhelming pressures and threats placed on the natural resources by a growing population and climate change. Traditional medicine plays an important role in the daily lives of the Malagasy for various reasons including limited access to healthcare, limited markets and traditional values. The objective of this study was to assess the modern utitilization of the Agnalazaha Forest by the local population in Mahabo-Mananivo, Madagascar, for medicinal plants used by women, and to establish a list of medicinal plants used by women sourced from Agnalazaha Forest. Methods Ethnobotanical studies were conducted over a period of five months in 2010 to determine the diversity of medicinal plants used by women in the commune of Mahabo-Mananivo. In all, 498 people were interviewed, both male and female ranging age from 15 to over 60 years old. Results 152 medicinal plants used by local people were collected during the ethnobotanical studies. Among the recorded species, eight native species are widely used by women. These species are known for their therapeutic properties in treating placental apposition and complications during childbirth as well as tropical illnesses such as malaria, filariasis, and sexual diseases like gonorrhea and syphilis. Conclusions Littoral forests are rare ecosystems that are highly threatened on the island nation of Madagascar. Our investigation into the use of medicinal plants sourced from and around the Agnalazaha Forest by the women of Mahabo-Mananivo reinforces the need for this natural resource as a first line of health care for rural families. PMID:24188563

2013-01-01

225

Tectonic significance of granitoid plutons from the Andasibe paragneiss belt, east-central Madagascar  

NASA Astrophysics Data System (ADS)

The understanding of the crustal evolution of the central Madagascar is of major significance in the study of the Precambrian basement of Madagascar and the greater Gondwana supercontinent. The study area, known as Andasibe paragneiss defines a fold belt that stretches from Ambatondrazaka to Soavina area in eastern Madagascar and is intruded by extensive granitoid intrusions. The western part of Andasibe paragneiss lies within the crustal scale Angavo shear zone, and is characterized by fine to medium-grained foliated paragneiss, which also include biotite-hornblende gneiss, migmatitic quartzofeldspathic gneiss, sillimanite-bearing gneiss, garnet-bearing gneiss, graphitic gneiss intercalates with schist, quartzite, muscovite-bearing gneiss and marble. Three samples of granitoid plutons intruding the Andasibe paragneiss yielded isotope dilution-thermal ionization mass spectrometry (ID-TIMS) U-Pb zircon ages of 801.2×3.8Ma, 776.5×4.4Ma and 772.1×4.2Ma. These dates are interpreted to represent the crystallization ages of these rocks and are comparable to other reported U-Pb emplacement ages for granitoid plutons within and along the north-central margin of the Angavo shear zone, which are suggested to be related to ca. 820 Ma successor-arc plutonism. These granitoids pre-dates the Angavo shear zone and folds affecting the plutons foliation are believed to have formed during the East-African Orogen, which in this part of the Malagasy Precambrian basement, is considered to have associated with Neoproterozoic extensive magmatism ca. 820 Ma to 540 Ma.

Raharimahefa, T.

2013-12-01

226

Convergent evolution of chemical defense in poison frogs and arthropod prey between Madagascar and the Neotropics.  

PubMed

With few exceptions, aposematically colored poison frogs sequester defensive alkaloids, unchanged, from dietary arthropods. In the Neotropics, myrmicine and formicine ants and the siphonotid millipede Rhinotus purpureus are dietary sources for alkaloids in dendrobatid poison frogs, yet the arthropod sources for Mantella poison frogs in Madagascar remained unknown. We report GC-MS analyses of extracts of arthropods and microsympatric Malagasy poison frogs (Mantella) collected from Ranomafana, Madagascar. Arthropod sources for 11 "poison frog" alkaloids were discovered, 7 of which were also detected in microsympatric Mantella. These arthropod sources include three endemic Malagasy ants, Tetramorium electrum, Anochetus grandidieri, and Paratrechina amblyops (subfamilies Myrmicinae, Ponerinae, and Formicinae, respectively), and the pantropical tramp millipede R. purpureus. Two of these ant species, A. grandidieri and T. electrum, were also found in Mantella stomachs, and ants represented the dominant prey type (67.3% of 609 identified stomach arthropods). To our knowledge, detection of 5,8-disubstituted (ds) indolizidine iso-217B in T. electrum represents the first izidine having a branch point in its carbon skeleton to be identified from ants, and detection of 3,5-ds pyrrolizidine 251O in A. grandidieri represents the first ponerine ant proposed as a dietary source of poison frog alkaloids. Endemic Malagasy ants with defensive alkaloids (with the exception of Paratrechina) are not closely related to any Neotropical species sharing similar chemical defenses. Our results suggest convergent evolution for the acquisition of defensive alkaloids in these dietary ants, which may have been the critical prerequisite for subsequent convergence in poison frogs between Madagascar and the Neotropics. PMID:16087888

Clark, Valerie C; Raxworthy, Christopher J; Rakotomalala, Valérie; Sierwald, Petra; Fisher, Brian L

2005-08-16

227

New Material of Beelzebufo, a Hyperossified Frog (Amphibia: Anura) from the Late Cretaceous of Madagascar  

PubMed Central

The extant anuran fauna of Madagascar is exceptionally rich and almost completely endemic. In recent years, many new species have been described and understanding of the history and relationships of this fauna has been greatly advanced by molecular studies, but very little is known of the fossil history of frogs on the island. Beelzebufo ampinga, the first named pre-Holocene frog from Madagascar, was described in 2008 on the basis of numerous disarticulated cranial and postcranial elements from the Upper Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. These specimens documented the presence of a hyperossified taxon that differed strikingly from extant Malagasy frogs in its large size and heavy coarse cranial exostosis. Here we describe and analyse new, articulated, and more complete material of the skull, vertebral column, and hind limb, as well as additional isolated elements discovered since 2008. ?CT scans allow a detailed understanding of both internal and external morphology and permit a more accurate reconstruction. The new material shows Beelzebufo to have been even more bizarre than originally interpreted, with large posterolateral skull flanges and sculptured vertebral spine tables. The apparent absence of a tympanic membrane, the strong cranial exostosis, and vertebral morphology suggest it may have burrowed during seasonally arid conditions, which have been interpreted for the Maevarano Formation from independent sedimentological and taphonomic evidence. New phylogenetic analyses, incorporating both morphological and molecular data, continue to place Beelzebufo with hyloid rather than ranoid frogs. Within Hyloidea, Beelzebufo still groups with the South American Ceratophryidae thus continuing to pose difficulties with both biogeographic interpretations and prior molecular divergence dates. PMID:24489877

Evans, Susan E.; Groenke, Joseph R.; Jones, Marc E. H.; Turner, Alan H.; Krause, David W.

2014-01-01

228

Low levels of family planning knowledge and use threaten Madagascar population goals.  

PubMed

1992 Madagascar Demographic and Health Survey (DHS) data indicate that Madagascar has a long way to go in order to realize its 1990 National Population Policy Law goal of reducing fertility from 6.1 to 4.0 by the year 2000. Madagascar DHS data are based upon a nationally representative sample of 6260 women aged 15-49. Only 62% of sampled women in union knew a modern method of contraception and 45% knew where they could obtain one. 56% of rural women and 38% of women with no education were similarly knowledgeable. Injection, the pill, and female sterilization are the best known modern methods. The infrequent airing and limited reach of family planning messages found only 6% of respondents reporting hearing a family planning message on the radio or television in the month preceding the survey. An aggressive and widespread information, education, and communication program is therefore needed to increase the level of knowledge about modern contraceptive methods. There is considerable unmet need for family planning in Madagascar. 40% of married women in 1992 reported that they did not want to have any more children, while another 30% reported wanting to space their next birth. Only 5% of married women, however, were then currently using modern methods, and 12% were using traditional methods, mainly periodic abstinence. As for maternal and child health, 163 children under five years old die per 1000 births, with the level of mortality inversely related to the level of education attained by the mother. The under-five mortality rate is 183/1000 in rural areas and 142/1000 in urban areas. In 1992, 78% of mothers received antenatal care from an health professional, and an health professional was present at delivery for 57% of births. Only 43% of children aged 12-23 months, however, have received all recommended vaccinations, such that childhood illnesses, particularly diarrhea, are common among young children. More than 50% of children under five are stunted, and 40% are underweight. PMID:12319376

1995-01-01

229

Leptopsyllines from Madagascar (Insecta: Siphonaptera: Ceratophyllidae): description of five new species of Paractenopsyllus Wagner, 1938.  

PubMed

Five new species of the malagasy endemic genus Paractenopsyllus Wagner, 1938, are described. Paractenopsyllus rouxi, P. ratovonjatoi, P. duplantieri, P. juliamarinus and P. gemelli have been collected on endemic small mammals and the black rat. Biotopes are mid-elevation rain-forests of the central highlands or the northern mountains of Madagascar. Morphological affinities between these new species and those already known provide taxonomic links within the genus. Differences in the spatial and altitudinal distributions and host ranges allow discussion of the potential factors important in the species distribution of this genus. PMID:15071828

Duchemin, J B

2004-03-01

230

Home Sweet Home: How to Build a Madagascar Hissing Cockroach Habitat Out of Recycled Materials  

NSDL National Science Digital Library

Madagascar hissing cockroaches (MHC) are amazing insects that can be an integral part of an effective science learning and teaching environment. MHCs have a fascinating social structure. They make excellent pets, teach students how to properly care for animals, and their large size adds to their âwowâ factor. These characteristics make them unique as classroom insects and add to their effectiveness in increasing your studentsâ scientific knowledge. This article provides directions for building a free, eco-friendly, low-maintenance MHC home out of garbage.

Wagler, Ron

2010-04-01

231

[A case of childhood granulomatous perioral dermatitis (CGPD) in a three year old boy from Madagascar].  

PubMed

A case of childhood granulomatous perioral dermatitis (CGPD)/facial Afro-Caribbean childhood eruption (FACE) in a three year old boy from Madagascar is described. This disorder occurs predominantly in black children until puberty. It is a relatively uncommon condition of unknown aetiology characterized by a monomorphic, papular eruption around the mouth, nose and eyes. The disorder looks like sarcoidosis, but it is benign and self-limited and not associated with any systemic manifestations. In our case we treated the patient with Elidel (pimecrolimus) with an excellent result. PMID:18252166

Mørtz, Charlotte Gotthard; Deleuran, Mette Søndergaard

2008-01-28

232

Is madagascar becoming increasingly vulnerable to food crises?  

Microsoft Academic Search

The physical need or status?quo approaches have not provided the appropriate conceptual framework for guiding food aid policies. As a response to this, models based on household or individual behavior are being articulated to explain food vulnerability. However, due to the complexity of these models and their data requirements, they have yet to become operational for the determination of food

M. Mahmud Khan; Nancy B. Mock; Victor Jeannoda; Shawn K. Baker

1993-01-01

233

http://www.jstor.org New Taxa and a New Rank of Selaginella (Selaginellaceae) from Madagascar and the Comoros  

E-print Network

http://www.jstor.org New Taxa and a New Rank of Selaginella (Selaginellaceae) from Madagascar), pp. 203-209 Published by: Missouri Botanical Garden Press Stable URL: http://www.jstor.org/stable/3391922 Accessed: 10/07/2008 10:48 Your use of the JSTOR archive indicates your acceptance of JSTOR

234

Well-Being Is a Process of Becoming: Respondent-Led Research with Organic Farmers in Madagascar  

ERIC Educational Resources Information Center

Malagasy "players"--farmers, middle men, organic organisations and policy makers--see in export-orientated organic agriculture a way for Madagascar to build upon its historic export strengths: spices, essential oils, medicinal plants and tropical fruits. They point to the "de facto" organic status of most farming in the country and view organic…

Farnworth, Cathy Rozel

2009-01-01

235

Comparison of the Jurassic and Cretaceous sedimentary cycles of Somalia and Madagascar: implications for the Gondwana breakup  

Microsoft Academic Search

The Jurassic and Cretaceous sedimentary history of northern Somalia and the Morondava Basin of south-western Madagascar have been studied. Both regions display an independent facial development; however, a comparison of the sequential evolution of the Mesozoic sedimentary successions in these two presently widely separated areas reveals a surprisingly high level of similarity, which probably reflects major events during the disintegration

Peter Luger; M. Gröschke; M. Bussmann; A. Dina; W. Mette; A. Uhmann; H. Kallenbach

1994-01-01

236

Inverting the impacts: Mining, conservation and sustainability claims near the Rio Tinto\\/QMM ilmenite mine in Southeast Madagascar  

Microsoft Academic Search

This paper traces a genealogy of land access and legitimization strategies culminating in the current convergence of mining and conservation in Southeast Madagascar, contributing to recent debates analyzing the commonalities and interdependencies between seemingly discrete types of land acquisitions. Drawing upon research carried out near the Rio Tinto\\/QMM ilmenite mine in 2009 (January–March), it focuses on how local Malagasy land

Caroline Seagle

2012-01-01

237

Competition or co-existence of reintroduced, critically endangered Mauritius fodies and invasive Madagascar fodies in lowland Mauritius?  

Microsoft Academic Search

Habitat destruction and introductions of invasive species have been primary causes of endemic species loss on oceanic islands. This paper addresses the question of whether a reintroduced population of a critically endangered island endemic, the Mauritius fody (Foudia rubra) is competing or co-existing with an exotic congener, the Madagascar fody (F. madagascariensis). We investigated habitat use and feeding ecology of

Lucy J. H. Garrett; Carl G. Jones; Andrew Cristinacce; Diana J. Bell

2007-01-01

238

Indigenous fruit trees of Madagascar: potential components of agroforestry systems to improve human nutrition and restore biological diversity  

Microsoft Academic Search

Biodiversity in Eastern Madagascar is threatened by slash and burn agriculture, which is resulting in species extinction, land and soil degradation and rural impoverishment. An ethnobotanical study was undertaken to determine the domestication potential of indigenous fruit tree species as components of agroforestry systems. Four major selection criteria were used: nutritional and income needs of the population, diversification of the

E. STYGER; R. RABEVOHITRA

1999-01-01

239

A method for quantifying biodiversity loss and its application to a 50-year record of deforestation across Madagascar  

E-print Network

of deforestation across Madagascar Thomas F. Allnutt1,2 , Simon Ferrier3,4 , Glenn Manion3 , George V. N. Powell1 Avenue, Pittsburgh, PA, 15213, USA Keywords Biodiversity loss; deforestation; endemism; extinction of deforestation and endemism. Deforestation has been extensive, but impacts of forest loss on biodiversity have

Vermont, University of

240

SIMULATION OF A TYPICAL HOUSE IN THE REGION OF ANTANANARIVO, MADAGASCAR DETERMINATION OF PASSIVE SOLUTIONS USING LOCAL MATERIALS  

E-print Network

superior to the national average [2]. However, the majority of the population lives in poorly designed solutions at an acceptable cost which also take into account the use of local materials and the living of living of the country. Keywords: Madagascar, Insulation, Passive solutions, Thermal comfort 1

Boyer, Edmond

241

Social Relationships Among Ring-Tailed Lemurs ( Lemur catta ) in Two Free-Ranging Troops at Berenty Reserve, Madagascar  

Microsoft Academic Search

We observed two free-ranging troops of ring-tailed lemurs at the Berenty Reserve, Madagascar. Kinship affinities in these troops are known only for mothers and their offspring =4 years of age. We attempted to quantify social relationships. Almost all agonistic interactions were dyadic, and triadic agonistic interactions, such as alliances, were very rare. Dominance hierarchies in both sexes in the two

Masayuki Nakamichi; Naoki Koyama

1997-01-01

242

Group Composition, Home Range Size, and Diet of Three Sympatric Bamboo Lemur Species (Genus Hapalemur ) in Ranomafana National Park, Madagascar  

Microsoft Academic Search

This is the first long-term, simultaneous, comparative study of three bamboo lemur species (Hapalemur griseus, H. aureus, and H. simus) at a site in southeastern-central Madagascar where they occur in sympatry. At Talatakely, Ranomafana National Park, the three Hapalemur spp. share overlapping home ranges. Hapalemur griseus has flexible group sizes, varying from three to nine individuals (n = 6). The

Chia L. Tan

1999-01-01

243

Effect of pruning history on growth and dry mass partitioning of jatropha on a plantation site in Madagascar  

Microsoft Academic Search

While technical aspects of oil processing of seeds of jatropha are under intensive investigation, comparably little is known about the performance of jatropha in the field. We investigated the effects of water availability (rainfed versus irrigated) and pruning-induced differences in plant stature on growth, biomass partitioning, and canopy size at a plantation site in Madagascar in 2010. Plants of different

Holger Brueck; Folkard Asch

244

Miocene benthic foraminifera from Nosy Makamby and Amparafaka, Mahajanga Basin, northwestern Madagascar  

NASA Astrophysics Data System (ADS)

Madagascar is well known for its fossil deposits and hosts one of the world's most important Upper Cretaceous terrestrial faunal sites (in the Mahajanga and Morondava Basins in the west and northwest of the island). Cenozoic marine fossils are also described from Madagascar, but these have received far less attention from the paleontological community, with most of this work dating from the 19th and early 20th centuries. Our study reports a new comprehensive microfossil assemblage from a Miocene sequence on the island of Nosy Makamby. After washing, sieving and sorting (?30 kg), twenty-five genera of foraminifera were identified including Alveolina, Ammodiscus, Ammonia, Archaias, Bolivina, Borelis, Cassidulina, Cyclammina, Cycloforina, Dentalina, Elphidium, Hauerina, Lagena, Lepidocyclina, Nodosaria, Nonion, Nonionella, Peneroplis, Pyrgo, Quinqueloculina, Rhabdammina, Spirillina, Spirolina, Spiroloculina and Triloculina. Ostracods are found in association with the foraminifera, as well as many other macroinvertebrate fossils (including bivalves, gastropods, and echinoids) in addition to vertebrate fossils. Together, the assemblage indicates that during the late Miocene, Nosy Makamby was a tropical, near-shore environment, probably similar to that seen today. Furthermore, the existence of epiphytic foraminiferans (e.g., Elphidium) suggests that sea-grass beds were likely present.

Ramihangihajason, Tolotra N.; Andrianavalona, Tsiory H.; Razafimbelo, Rachel; Rahantarisoa, Lydia; Ali, Jason R.; Samonds, Karen E.

2014-12-01

245

Seroprevalence of hepatitis C and associated risk factors in urban areas of Antananarivo, Madagascar  

PubMed Central

Background The risk factors for the transmission of HCV vary substantially between countries and geographic regions. The overall prevalence in south and east Africa region has been estimated to be 1.6% but limited information about the epidemiology of HCV infection in Madagascar is available Methods A cross-sectional survey for hepatitis C antibodies was conducted in 2,169 subjects of the general population of Antananarivo to determine seroprevalence of hepatitis C and associated risk factors. Results The overall seroprevalence was 1.2% (25/2,169). The prevalence did not differ significantly according to gender but it increased with age (Chi2 tendency test, p < 10-5). The variable history of hospitalization, previous therapeutic injections, dental treatment, intravenous drug use, and abnormal ALT and AST were statistically significantly related with the presence of HCV antibodies. No relationship with past history of blood transfusion was observed. Conclusion HCV prevalence in Madagascar seems to be similar to that in most other east African countries. Age appears to be an important risk factor. Iatrogenic causes of HCV transmission need to be further evaluated because all HCV cases had a history of receiving therapeutic injections and data suggested a cumulative effect in relation with therapeutic injections. PMID:18312652

Ramarokoto, Charles E; Rakotomanana, Fanjasoa; Ratsitorahina, Maherisoa; Raharimanga, Vaomalala; Razafindratsimandresy, Richter; Randremanana, Rindra; Rakoto-Andrianarivelo, Mala; Rousset, Dominique; Andrianaja, Voahangy; Richard, Vincent; Soares, Jean-Louis; Rabarijaona, Leon P

2008-01-01

246

DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar  

PubMed Central

The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods is tested using ants in Madagascar. We demonstrate how DNA barcoding helps address the failure of current inventory methods to rapidly respond to pressing biodiversity needs, specifically in the assessment of richness and turnover across landscapes with hyperdiverse taxa. In a comparison of inventories at four localities in northern Madagascar, patterns of richness were not significantly different when richness was determined using morphological taxonomy (morphospecies) or sequence divergence thresholds (Molecular Operational Taxonomic Unit(s); MOTU). However, sequence-based methods tended to yield greater richness and significantly lower indices of similarity than morphological taxonomy. MOTU determined using our molecular technique were a remarkably local phenomenon—indicative of highly restricted dispersal and/or long-term isolation. In cases where molecular and morphological methods differed in their assignment of individuals to categories, the morphological estimate was always more conservative than the molecular estimate. In those cases where morphospecies descriptions collapsed distinct molecular groups, sequence divergences of 16% (on average) were contained within the same morphospecies. Such high divergences highlight taxa for further detailed genetic, morphological, life history, and behavioral studies. PMID:16214741

Smith, M. Alex; Fisher, Brian L; Hebert, Paul D.N

2005-01-01

247

Multiple colonization of Madagascar and Socotra by colubrid snakes: evidence from nuclear and mitochondrial gene phylogenies.  

PubMed

Colubrid snakes form a speciose group of unclarified phylogeny. Their almost cosmopolitan distribution could be interpreted as a product of plate-tectonic vicariance. We used sequences of the nuclear c-mos, the mitochondrial cytochrome b and the 16S rRNA genes in 41 taxa to elucidate the relationships between the endemic colubrid genera found in Madagascar and in the Socotra archipelago. The well-resolved trees indicate multiple origins of both the Malagasy and the Socotran taxa. The Malagasy genus Mimophis was nested within the Psammophiinae, and the Socotran Hemerophis was closely related to Old World representatives of the former genus Coluber. The remaining 14 genera of Malagasy colubrids formed a monophyletic sister group of the Socotran Ditypophis (together forming the Pseudoxyrhophiinae). Molecular-clock estimates place the divergence of Malagasy and Socotran colubrids from their non-insular sister groups into a time-frame between the Eocene and Miocene. Over-seas rafting is the most likely hypothesis for the origin of at least the Malagasy taxa. The discovery of a large monophyletic clade of colubrids endemic to Madagascar indicates a need for taxonomic changes. The relationship of this radiation to the Socotran Ditypophis highlights the potential of the Indian Ocean islands to act as an evolutionary reservoir for lineages that have become extinct in Africa and Asia. PMID:14728785

Nagy, Zoltán Tamás; Joger, Ulrich; Wink, Michael; Glaw, Frank; Vences, Miguel

2003-12-22

248

The Settlement of Madagascar: What Dialects and Languages Can Tell Us  

PubMed Central

The dialects of Madagascar belong to the Greater Barito East group of the Austronesian family and it is widely accepted that the Island was colonized by Indonesian sailors after a maritime trek that probably took place around 650 CE. The language most closely related to Malagasy dialects is Maanyan, but Malay is also strongly related especially for navigation terms. Since the Maanyan Dayaks live along the Barito river in Kalimantan (Borneo) and they do not possess the necessary skill for long maritime navigation, they were probably brought as subordinates by Malay sailors. In a recent paper we compared 23 different Malagasy dialects in order to determine the time and the landing area of the first colonization. In this research we use new data and new methods to confirm that the landing took place on the south-east coast of the Island. Furthermore, we are able to state here that colonization probably consisted of a single founding event rather than multiple settlements.To reach our goal we find out the internal kinship relations among all the 23 Malagasy dialects and we also find out the relations of the 23 dialects to Malay and Maanyan. The method used is an automated version of the lexicostatistic approach. The data from Madagascar were collected by the author at the beginning of 2010 and consist of Swadesh lists of 200 items for 23 dialects covering all areas of the Island. The lists for Maanyan and Malay were obtained from a published dataset integrated with the author's interviews. PMID:22363465

Serva, Maurizio

2012-01-01

249

Bird fossils from Ankilitelo Cave: inference about Holocene environmental changes in southwestern Madagascar.  

PubMed

The identifications of non-permineralized fossil bird bones recovered from Ankilitelo Cave in southwestern Madagascar are presented. Among the more than 560 elements recovered, 29 different taxa were identified, the vast majority being species that still occur in this region of the island. Eggshell remains from the extinct elephant bird (Family Aepyornithidae) and assigned to Aepyornis sp. were found at the site. Two identified extant taxa, Scopus umbretta and Monias benschi, no longer occur in the area immediately surrounding the cave. The available radiocarbon measurements of collagen from fossil bird bones and avian eggshell carbonate of recovered from the cave range from 13,270 Cal yr BP to modern times. Hence, the presumed ecological shifts that took place resulting in the disappearance or range contractions of these three taxa is within the Holocene and are presumed to be associated with natural climatic change and in more recent centuries associated human pressures. Information is also presented on the origin of guinea fowl (Numida) and inference on the period of colonization of Corvus albus on Madagascar.  PMID:25113715

Goodman, Steven M; Raherilalao, Marie Jeanne; Muldoon, Kathleen

2013-01-01

250

Invasion genetics of a human commensal rodent: the black rat Rattus rattus in Madagascar.  

PubMed

Studies focusing on geographical genetic patterns of commensal species and on human history complement each other and provide proxies to trace common colonization events. On Madagascar, the unintentional introduction and spread of the commensal species Rattus rattus by people may have left a living clue of human colonization patterns and history. In this study, we addressed this question by characterizing the genetic structure of natural populations of R. rattus using both microsatellites and mitochondrial sequences, on an extensive sampling across the island. Such data sets were analysed by a combination of methods using population genetics, phylogeography and approximate Bayesian computation. Our results indicated two introduction events to Madagascar from the same ancestral source of R. rattus, one in the extreme north of the island and the other further south. The latter was the source of a large spatial expansion, which may have initially started from an original point located on the southern coast. The inferred timing of introduction events-several centuries ago-is temporally congruent with the Arabian trade network in the Indian Ocean, which was flourishing from the middle of the first millennium. PMID:24975563

Brouat, C; Tollenaere, C; Estoup, A; Loiseau, A; Sommer, S; Soanandrasana, R; Rahalison, L; Rajerison, M; Piry, S; Goodman, S M; Duplantier, J-M

2014-08-01

251

Multiple colonization of Madagascar and Socotra by colubrid snakes: evidence from nuclear and mitochondrial gene phylogenies.  

PubMed Central

Colubrid snakes form a speciose group of unclarified phylogeny. Their almost cosmopolitan distribution could be interpreted as a product of plate-tectonic vicariance. We used sequences of the nuclear c-mos, the mitochondrial cytochrome b and the 16S rRNA genes in 41 taxa to elucidate the relationships between the endemic colubrid genera found in Madagascar and in the Socotra archipelago. The well-resolved trees indicate multiple origins of both the Malagasy and the Socotran taxa. The Malagasy genus Mimophis was nested within the Psammophiinae, and the Socotran Hemerophis was closely related to Old World representatives of the former genus Coluber. The remaining 14 genera of Malagasy colubrids formed a monophyletic sister group of the Socotran Ditypophis (together forming the Pseudoxyrhophiinae). Molecular-clock estimates place the divergence of Malagasy and Socotran colubrids from their non-insular sister groups into a time-frame between the Eocene and Miocene. Over-seas rafting is the most likely hypothesis for the origin of at least the Malagasy taxa. The discovery of a large monophyletic clade of colubrids endemic to Madagascar indicates a need for taxonomic changes. The relationship of this radiation to the Socotran Ditypophis highlights the potential of the Indian Ocean islands to act as an evolutionary reservoir for lineages that have become extinct in Africa and Asia. PMID:14728785

Nagy, Zoltan Tamas; Joger, Ulrich; Wink, Michael; Glaw, Frank; Vences, Miguel

2003-01-01

252

Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.  

PubMed

In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10? bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (< 5,000 bacteria), delayed mortality was observed and surviving seronegative rats were not uncommon. These results concerning plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar. PMID:20443044

Tollenaere, C; Rahalison, L; Ranjalahy, M; Duplantier, J-M; Rahelinirina, S; Telfer, S; Brouat, C

2010-06-01

253

[Rice: source of life and death on the plateaux of Madagascar].  

PubMed

Since the 17th century, Europeans travelling in Madagascar described the contrast between the fever-free Plateau and the fever-ridden coasts. The former were inhabited by people of Asiatic origins and the latter by African migrants. At the end of the 18th century, "Merina" kings developed land irrigation and rice cultivation, using manpower from the coasts. Since then, rice has become a monoculture covering most of the arable lands of the Highlands. The first malaria epidemic occurred in the Tananarive area in 1878, and rapidly spread throughout the Plateau. The mortality rate was high. A second epidemic in 1895 may have been a resurgence of the previous one. Subsequently, malaria became meso-epidemic despite control measures, mainly consisting of larvivorous fishes, quinine treatment and prophylaxis. In 1949, an eradication program was launched based on DDT house-spraying and chloroquine prophylaxis in children. It was very successful on the Highlands where malaria disappeared, in 1962. Spraying was cancelled and only three small foci remained under surveillance. In 1987 and 1988, a malaria outbreak devastated the plateau. Subsequently, intensive spraying operations brought the situation under control by 1993. The main malaria vector on the Madagascar Highlands is An. funestus. More than 95% of its breeding sites are in the rice fields just before the harvest and afterwards in the fallow lands. The vector peak and the corresponding peak of malaria cases occur between February and May, depending on the farming calender. The second but less important vector, An. arabiensis, breeds in the rice fields just after seeding when the surface water is sunlit. Although rice fields remain the main source of this vector, it also breeds in rainwater pods and borow-pits. Malaria vectors on the plateau are products of human activities of rice cultivation, which is the basis of the economy. The epidemiological importance of rice fields varies greatly from one country to another. In Southeast Asia, the rice fields harbor several anopheline species most of which are only vectors of P. vivax. In West Africa where malaria is holoendemic, they produce large populations of An. gambiae; however, the malaria pattern is unaltered and remains at peak levels. In the dry areas of southern Madagascar, the vector An. funestus and meso-hyperendemic malaria are restricted to areas of cultivated rice. In West and Central Africa, An. funestus is never found in rice fields even though it is common in marshes. In Madagascar, this vector breeds in irrigated rice fields. Because it is practically impossible to control anophelines in rice fields by chemical, biological and ecological methods on the Highlands of Madagascar, house-spraying remains the best method for mass malaria control. Bed-nets impregnated with pesticides may offer an alternative, but their use is resisted by the local population. PMID:8705134

Laventure, S; Mouchet, J; Blanchy, S; Marrama, L; Rabarison, P; Andrianaivolambo, L; Rajaonarivelo, E; Rakotoarivony, I; Roux, J

1996-01-01

254

In and out of Madagascar: dispersal to peripheral islands, insular speciation and diversification of Indian Ocean daisy trees (Psiadia, Asteraceae).  

PubMed

Madagascar is surrounded by archipelagos varying widely in origin, age and structure. Although small and geologically young, these archipelagos have accumulated disproportionate numbers of unique lineages in comparison to Madagascar, highlighting the role of waif-dispersal and rapid in situ diversification processes in generating endemic biodiversity. We reconstruct the evolutionary and biogeographical history of the genus Psiadia (Asteraceae), a plant genus with near equal numbers of species in Madagascar and surrounding islands. Analyzing patterns and processes of diversification, we explain species accumulation on peripheral islands and aim to offer new insights on the origin and potential causes for diversification in the Madagascar and Indian Ocean Islands biodiversity hotspot. Our results provide support for an African origin of the group, with strong support for non-monophyly. Colonization of the Mascarenes took place by two evolutionary distinct lineages from Madagascar, via two independent dispersal events, each unique for their spatial and temporal properties. Significant shifts in diversification rate followed regional expansion, resulting in co-occurring and phenotypically convergent species on high-elevation volcanic slopes. Like other endemic island lineages, Psiadia have been highly successful in dispersing to and radiating on isolated oceanic islands, typified by high habitat diversity and dynamic ecosystems fuelled by continued geological activity. Results stress the important biogeographical role for Rodrigues in serving as an outlying stepping stone from which regional colonization took place. We discuss how isolated volcanic islands contribute to regional diversity by generating substantial numbers of endemic species on short temporal scales. Factors pertaining to the mode and tempo of archipelago formation and its geographical isolation strongly govern evolutionary pathways available for species diversification, and the potential for successful diversification of dispersed lineages, therefore, appears highly dependent on the timing of arrival, as habitat and resource properties change dramatically over the course of oceanic island evolution. PMID:22900068

Strijk, Joeri S; Noyes, Richard D; Strasberg, Dominique; Cruaud, Corinne; Gavory, Fredéric; Chase, Mark W; Abbott, Richard J; Thébaud, Christophe

2012-01-01

255

Accumulation of Monoterpenoid Indole Alkaloids in Periwinkle Seedlings ("Catharanthus roseus") as a Model for the Study of Plant-Environment Interactions  

ERIC Educational Resources Information Center

Alkaloids are part of the chemical arsenal designed to protect plants against an adverse environment. Therefore, their synthesis and accumulation are frequently induced in response to certain environmental conditions and are mediated by chemical signals, which are formed as the first responses to the external stimulus. A set of experiments using…

Miranda-Ham, Maria de Lourdes; Islas-Flores, Ignacio; Vazquez-Flota, Felipe

2007-01-01

256

Global warming and extinction risks for amphibians in Madagascar, an Franco Andreone, Museo Regionale di Scienze Naturali and Amphibian Specialist Group /  

E-print Network

Global warming and extinction risks for amphibians in Madagascar, an overview Franco Andreone be ideally interpreted within the framework of the global climate change. This gap was filled up in the last

Andreone, Franco

257

Premier cas d'un sub-fossile d'araignée appartenant au genre Archaea Koch & Berendt (Archaeidae) dans le copal de Madagascar  

NASA Astrophysics Data System (ADS)

The first known case of a sub-fossil of a spider belonging to the genus Archaea from the Madagascan copal. The first known sub-fossil of a spider belonging to the genus Archaea Koch & Berendt is described from the Copal of Madagascar. The new species was found in the Province of Antseranana (Diego-Suarez) in the northern part of the island. It belongs to the family Archaeidae. The genus Archaea is endemic in Madagascar.

Lourenço, Wilson R.

2000-04-01

258

Cover sequences at the northern margin of the Antongil Craton, NE Madagascar  

USGS Publications Warehouse

The island of Madagascar is a collage of Precambrian, generally high-grade metamorphic basement domains, that are locally overlain by unmetamorphosed sedimentary rocks and poorly understood low-grade metasediments. In the Antalaha area of NE Madagascar, two distinct cover sequences rest on high-grade metamorphic and igneous basement rocks of the Archaean Antongil craton and the Neoproterozoic Bemarivo belt. The older of these two cover sequences, the Andrarona Group, consists of low-grade metasedimentary rocks. The younger sequence, the newly defined Ampohafana Formation, consists of unmetamorphosed sedimentary rocks. The Andrarona Group rests on Neoarchaean granites and monzogranites of the Antongil craton and consists of a basal metagreywacke, thick quartzites and an upper sequence of sericite-chlorite meta-mudstones, meta-sandstones and a volcaniclastic meta-sandstone. The depositional age of the volcaniclastic meta-sandstone is constrained in age by U–Pb laser-ablation ICP-MS analyses of euhedral zircons to 1875 ± 8 Ma (2?). Detrital zircons of Archaean and Palaeoproterozoic age represent an input from the Antongil craton and a newly defined Palaeoproterozoic igneous unit, the Masindray tonalite, which underlies the Andrarona Group, and yielded a U–Pb zircon age of 2355 ± 11 Ma (2?), thus constraining the maximum age of deposition of the basal part of the Andrarona Group. The Andrarona Group shows a low-grade metamorphic overprint in the area near Antalaha; illite crystallinity values scatter around 0.17°?2? CuK?, which is within the epizone. The Ampohafana Formation consists of undeformed, polymict conglomerate, cross-bedded sandstone, and red mudstone. An illite crystallinity value of >0.25°?2? CuK? obtained from the rocks is typical of the diagenetic zone. Occurrences of rhyodacite pebbles in the Ampohafana Formation and the intrusion of a basaltic dyke suggest a deposition in a WSW-ENE-trending graben system during the opening of the Indian Ocean in the Upper Cretaceous, that was characterized by extensive rhyolitic to basaltic magmatism along Madagascar's eastern coast.

Bauer, W.; Walsh, G. J.; de Waele, B.; Thomas, R. J.; Horstwood, M. S. A.; Bracciali, L.; Schofield, D. I.; Wollenberg, U.; Lidke, D. J.; Rasaona, I. T.; Rabarimanana, M. H.

2011-01-01

259

Malagasyprinus, a new genus of the Saprininae from Madagascar with description of two new species (Coleoptera, Histeridae, Saprininae) (First contribution to the knowledge of the Histeridae of Madagascar)  

PubMed Central

Abstract Based on the results of recent phylogenetic analysis of the higher taxa of the Saprininae as well as external morphological characters, especially the presence of deep and large prosternal foveae, and the shape and position of the sensory organs of the antennal club, the species Saprinus (s.str.) caeruleatus Lewis, 1905 is excluded from the genus Saprinus and a new genus Malagasyprinus, exclusive to Madagascar, is established for it. The new genus shows mainly characters that are apomorphic for the subfamily and contains another two, highly similar allopatric species Malagasyprinus perrieri sp. n., and Malagasyprinus diana sp. n., described herein. The three species are best separated from each other by the structure of the prosternum and male terminalia, especially the shape of the aedeagus. We re-describe Malagasyprinus caeruleatus comb. n. and provide Malagasyprinus perrieri and Malagasyprinus diana with brief differential diagnoses. All taxon descriptions are accompanied with color habitat photographs, SEM micrographs and drawings of their male genitalia. A key to the species of Malagasyprinus is given. Sensory structures of the antenna of Malagasyprinus caeruleatus comb. n. are likewise depicted herein. The systematic position of the newly erected genus is discussed. A lectotype of Saprinus caeruleatus Lewis, 1905 is designated. PMID:24146560

Lackner, Tomas; Gomy, Yves

2013-01-01

260

A new and aberrant species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Madagascar.  

PubMed

In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia. PMID:25147450

Stocchino, Giacinta Angela; Sluys, Ronald; Manconi, Renata

2014-01-01

261

Animal health studies using participatory epidemiology in the Mandrare Valley, Madagascar.  

PubMed

Pastoral herders in Madagascar have limited access to animal health workers and veterinary medicines, and more information on their livestock diseases is needed, so that effective animal health programmes can be implemented. In this study, participatory epidemiology methods were used to gather such information in the Mandrare Valley. These included pair-wise ranking and matrix scoring. Eleven diseases were deemed to be priorities by pair-wise ranking. Matrix scoring and characterisation showed that the informant groups associated many disease syndromes with the same diseases, indicating agreement and understanding of the key diseases. The Malagasy-named syndromes, Soko, Besorko and Mamany lio, which are gastrointestinal parasitism, clostridial disease and babesiosis, respectively, were identified by every informant group. A greater sample size may be needed to characterise the diseases precisely with matrix scoring because, in this study, the matrices' scores had wide confidence intervals. PMID:23999777

Bardsley, Elise L; Thrusfield, Michael V

2014-01-01

262

Troop fission in wild ring-tailed lemurs (Lemur catta) at Berenty, Madagascar.  

PubMed

A detailed fission process in a wild ring-tailed lemur (Lemur catta) troop was observed at Berenty Reserve, Madagascar. The troop fission occurred as follows: 1) During the birth season in 2000, two adult females (mother and daughter) were evicted as a result of "targeted aggression" (i.e., intense and persistent aggressive behavior toward particular individuals). 2) Two adult and three immature females in the same kin group as the evicted females spontaneously immigrated into the new group. 3) A male immigrated into the new group 1.5 months later. 4) The new troop successfully established its own home range. This report exemplifies three characteristics of troop fission in ring-tailed lemurs. First, targeted aggression initiated the fission process. Second, the troop females divided along matrilineal lines. Finally, no male played a specific role in the fission process. PMID:16419123

Ichino, Shinichiro

2006-01-01

263

Pilot survey of avahi population (woolly lemurs) in littoral forest fragments of southeast Madagascar.  

PubMed

This study presents a pilot survey of the avahis (pair-living, nocturnal prosimians) living in threatened littoral forest fragments of southeastern Madagascar. In the period of October-December 2004, I evaluated the density of adult and newborn avahis (carried by the mothers) by counting the individuals encountered during 58 night walks in seven fragments of Sainte Luce and Mandena forests, along one trail/fragment. Along each trail, I used random plots (5 m2) for a preliminary characterization of the vegetation. The density of the population was not correlated with fragment size and number of plant morphospecies, while it was correlated with large tree availability. Possibly due to a low energy diet based on leaves and to specialized and energetically expensive vertical leaping, the loss of large trees by selective logging seems to affect avahi populations more than other variables. PMID:17805480

Norscia, Ivan

2008-01-01

264

Impact of the Safe Water System on Water Quality in Cyclone-Affected Communities in Madagascar  

PubMed Central

Cyclone Hudah struck the northeastern coast of Madagascar in the spring of 2000. Over a 5-month period, 11 700 relief kits consisting of bottles of water disinfectant and foldable jerry cans were distributed to the affected population. Five months after the cyclone, a survey was conducted in 12 villages to determine the impact of these relief kits on water quality. Seventy-six percent of the surveyed households reported using jerry cans, and 65% reported using the disinfectant. Stored water in households using both products had significantly less microbiological contamination than stored water in other households. To improve the prospects for a sustainable intervention, the response plan for future disasters should incorporate a transition to recovery and development, including formative research into local customs, beliefs, and water handling habits, and funding support to initiate social marketing. PMID:11574310

Mong, Yves; Kaiser, Reinhard; Ibrahim, Dasy; Rasoatiana; Razafimbololona, Lalaina; Quick, Robert E.

2001-01-01

265

Thermoluminescence External Personnel Monitoring of Workers in Diagnostic Radiology in Madagascar  

NASA Astrophysics Data System (ADS)

Results of thermoluminescence personnel external monitoring are reported from 1990 to 2000 for workers in diagnostic radiology which represents more than 75% of the professional exposure in Madagascar and for which enough data for good statistical considerations are available. Average and individual doses distribution are presented. In most cases, compliance with dose limits is verified though some high exposures have been identified. Globaly, these doses can be compared with the average effective dose from natural radiation sources. Methods for the evaluation of quality and performance are presented as long as the doses measured are all in the low range. In radiation protection, an important principle is to meet the requirements of the implementation of ALARA, in order to limit or reduce exposures. This work can be used as reference for decision makers for corrective measures or further investigation when substantial variation in average doses is observed.

Andriambololona, Raoelina; Ratovonjanahary, J. F.; Randriantsizafy, R. D.; Rakotoson, E.; Razafindrabe, R. L.

2002-07-01

266

[Premarital sex in Antananarivo (Madagascar): how are students freeing themselves from the norms?].  

PubMed

This paper aims to analyze the representations of premarital sexuality among young people in a context where they are strongly encouraged not to engage in premarital sexual relations. This link between prevention messages, representations and behaviours has been studied among a student population in Madagascar. The analysis is based on a socio-demographic survey conducted in 2006. Results show that young men and women share the ideal of abstinence before marriage. The promotion of premarital sexual abstinence within AIDS programs reinforces gender differences. It is mainly young women who are urged to be abstinent, whereas young men have the means--condom use--to transgress the taboo of premarital sex and protect themselves against health risks. Thus, young men have a dual strategy. On the one hand, they attach great importance to premarital abstinence with their future wife; on the other hand, they can have sex with occasional partners and are then protected by condoms. PMID:24069762

Gastineau, Bénédicte; Binet, Clotilde

2013-06-01

267

Introducing auto-disable syringes to the national immunization programme in Madagascar.  

PubMed Central

OBJECTIVE: To evaluate the safety and coverage benefits of auto-disable (AD) syringes, weighed against the financial and logis- tical costs, and to create appropriate health policies in Madagascar. METHODS: Fifteen clinics in Madagascar, trained to use AD syringes, were randomized to implement an AD syringe only, mixed (AD syringes used only on non-routine immunization days), or sterilizable syringe only (control) programme. During a five-week period, data on administered vaccinations were collected, interviews were conducted, and observations were recorded. FINDINGS: The use of AD syringes improved coverage rates by significantly increasing the percentage of vaccines administered on non-routine immunization days (AD-only 4.3%, mixed 5.7%, control 1.1% (P<0.05)). AD-only clinics eliminated sterilization sessions for vaccinations, whereas mixed clinics reduced the number of sterilization sessions by 64%. AD syringes were five times more expensive than sterilizable syringes, which increased AD-only and mixed clinics' projected annual injection costs by 365% and 22%, respectively. However, introducing AD syringes for all vaccinations would only increase the national immunization budget by 2%. CONCLUSION: The use of AD syringes improved vaccination coverage rates by providing ready-to-use sterile syringes on non-routine immunization days and decreasing the number of sterilization sessions, thereby improving injection safety. The mixed programme was the most beneficial approach to phasing in AD syringes and diminishing logistical complications, and it had minimal costs. AD syringes, although more expensive, can feasibly be introduced into a developing country's immunization programme to improve vaccination safety and coverage. PMID:14576886

Drain, Paul K.; Ralaivao, Josoa S.; Rakotonandrasana, Alexander; Carnell, Mary A.

2003-01-01

268

A Genome Sequence Resource for the Aye-Aye (Daubentonia madagascariensis), a Nocturnal Lemur from Madagascar  

PubMed Central

We present a high-coverage draft genome assembly of the aye-aye (Daubentonia madagascariensis), a highly unusual nocturnal primate from Madagascar. Our assembly totals ?3.0 billion bp (3.0 Gb), roughly the size of the human genome, comprised of ?2.6 million scaffolds (N50 scaffold size = 13,597 bp) based on short paired-end sequencing reads. We compared the aye-aye genome sequence data with four other published primate genomes (human, chimpanzee, orangutan, and rhesus macaque) as well as with the mouse and dog genomes as nonprimate outgroups. Unexpectedly, we observed strong evidence for a relatively slow substitution rate in the aye-aye lineage compared with these and other primates. In fact, the aye-aye branch length is estimated to be ?10% shorter than that of the human lineage, which is known for its low substitution rate. This finding may be explained, in part, by the protracted aye-aye life-history pattern, including late weaning and age of first reproduction relative to other lemurs. Additionally, the availability of this draft lemur genome sequence allowed us to polarize nucleotide and protein sequence changes to the ancestral primate lineage—a critical period in primate evolution, for which the relevant fossil record is sparse. Finally, we identified 293,800 high-confidence single nucleotide polymorphisms in the donor individual for our aye-aye genome sequence, a captive-born individual from two wild-born parents. The resulting heterozygosity estimate of 0.051% is the lowest of any primate studied to date, which is understandable considering the aye-aye's extensive home-range size and relatively low population densities. Yet this level of genetic diversity also suggests that conservation efforts benefiting this unusual species should be prioritized, especially in the face of the accelerating degradation and fragmentation of Madagascar's forests. PMID:22155688

Perry, George H.; Reeves, Darryl; Melsted, Pall; Ratan, Aakrosh; Miller, Webb; Michelini, Katelyn; Louis, Edward E.; Pritchard, Jonathan K.; Mason, Christopher E.; Gilad, Yoav

2012-01-01

269

Forest Management Devolution: Gap Between Technicians' Design and Villagers' Practices in Madagascar  

NASA Astrophysics Data System (ADS)

In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.

Rives, Fanny; Carrière, Stéphanie M.; Montagne, Pierre; Aubert, Sigrid; Sibelet, Nicole

2013-10-01

270

The origin and dispersion of human parasitic diseases in the old world (Africa, Europe and Madagascar).  

PubMed

The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani--the dog--has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar). Migrants coming from Africa and Arabia brought with them the two African forms of bilharziosis: S. haematobium and S. mansoni. PMID:12687757

Nozais, Jean-Pierre

2003-01-01

271

Lost in translation: conflicting views of deforestation, land use and identity in western Madagascar.  

PubMed

This paper focuses on the interplay between environmental narratives, identity politics and the management of forest resources in Madagascar. While efforts to conserve the island's biological diversity have centred primarily on the designation of protected areas, policies have increasingly focused on local communities. The experiences of the last 20 years have shown that community-based approaches to conservation offer considerable challenges due to the complex politics of natural resource use, which involve multiple and diverse stakeholders, often with very different and sometimes conflicting values. In this paper, I focus on the environmental perceptions and values of two groups in the Central Menabe region of western Madagascar – conservation organisations and rural households – revealing a contrasting set of views regarding the region's forest. I show that the conservation discourse has changed over time, increasingly emphasising the biological diversity of the region's tropical dry-deciduous forest and prioritising non-consumptive uses of natural resources. Although policy has changed in response to changing values, I show that it has been underpinned by the notion that hatsake (‘slash-and-burn’ agriculture) is an irrational practice driven by necessity rather than choice. Policy has thus sought to provide livelihood alternatives, firstly through forestry, then through changes in cultivation and increasingly through tourism. This misunderstands the local view of the forest, which sees hatsake as a way to make the land productive, as long as it is carried out responsibly according to local fady (taboos). As well as facing problems of translating conservation goals into local values and misunderstanding the motives for forest clearance, policy has been based on a narrative that attaches particular land use practices to ethnic identities. I argue that this ignores the history and fluid reality of both identity and land use. PMID:22413174

Scales, Ivan R

2012-01-01

272

Madagascar Highland erosion: What can we learn from the archive precipitation data?  

NASA Astrophysics Data System (ADS)

In Madagascar, soil erosion is significant even when it is compared to world averages, resulting in special geomorphic forms known as lavakas appearing in the Highland regions of the island. The development of these features is due to rather unique multifactorial environmental conditions. Among many factors (geology, soil composition, human influence, etc.) the spatial and temporal distribution of precipitation is a key factor. The presence of the dry and wet season seems to be responsible for the enhanced generation of small cracks that might eventually lead to the development of a gully. However, the way of the development of such gully erosions are unknown. To what extent of the actual precipitation pattern to what extent the weather contributes to the aforementioned phenomenon has not yet been studied in great detail. The aim of our research is to study the climatic and weather conditions of lavaka-prone areas for the last decades. The typical cyclonal pattern affects the Madagascar Highlands in various ways. The precipitation and the soil moisture data show that the spatial distribution can be correlated with the appearance of lavakas to a given extent, however the local distribution cannot be explained only based on the precipitation pattern. The severity of the wet season varies strongly in the various decades leading to different precipitation maxima in January-March period. In general the effectiveness of the gully erosion is thought to be highly enhanced if the run-off of the area show large temporal variations. According to our studies this variability is quite high in certain seasons, and, despite of the low spatial resolution, related to the lavaka-prone areas. However, neither the amount of the precipitation, nor the variability alone cannot explain the high variation found in the spatial density and length distribution. Further multidisciplinary studies are necessary to draw conclusions about lavaka formation and describe the process of lavaka development. This is ILARG-contribution Nr. 11.

Imola Szabó, Amanda; Raveloson, Andrea; Székely, Balázs

2014-05-01

273

Petrogenesis of high-K metagranites in the Kerala Khondalite Belt, southern India: a possible magmatic-arc link between India, Sri Lanka, and Madagascar  

NASA Astrophysics Data System (ADS)

The Proterozoic Kerala Khondalite Belt (KKB), southern India preserves a distinct high-grade terrain that is interpreted to have been situated adjacent to Madagascar and Sri Lanka during Gondwana assembly. As such, it has become a major focus for testing models of supercontinent amalgamation and dispersal. The lithounits of KKB have remarkable petrological similarities to the Highland Complex (HC) of Sri Lanka and south-central Madagascar. However, there is no well-constrained petrogenetic model for the KKB that fits explicitly within a supercontinent reconstruction model. We present here results from our on-going studies on the origin and evolution of K-rich (potassic, where K2O/Na2O > 1) gneisses of KKB in relation to Proterozoic supercontinent events. Our results show, in a major departure from earlier metasedimentary origin, that potassic gneisses are metamorphosed granitoids. The metagranitoid samples display high K2O contents and low Al2O3/(FeO + MgO + TiO2) values. They are moderate to strongly peraluminous (ASI values ranging from 1.05 to 1.47) rocks showing mineralogical, petrological, and geochemical characteristics distinctive of the high-K calc-alkaline suites. Typical of igneous suites, the high-K metagranites show minor variation in chemical compositions with most oxides showing negative correlation with SiO2. Geochemistry illustrates distinctive features of arc-related magmas with LILE (K, Rb, and Th) and LREE enriched patterns and considerable depletion of HSFE (Nb, Zr, and Ti). The high-K metagranites are further characterized by strong negative anomalies of Eu (Eu/Eu* = 0.10-0.44) and Sr, suggesting melting in plagioclase stability field and retention of plagioclase in the residual phase. Petrogenetic discrimination for granitoids, using major and trace elements demonstrates that the high-K metagranites of the KKB formed by partial melting of igneous source in lower- to middle-crust levels. Overall the geochemical features are supportive of origin in relation to a convergent margin setting, possibly in a continental magmatic arc system, which can be connected to the amalgamation and dispersal of continental fragments in a supercontinent event. This study, therefore, provides a lead towards more robust comparisons between the Proterozoic supercontinent events and processes.

Sreejith, C.; Ravindra Kumar, G. R.

2013-01-01

274

Metabolism and temperature regulation during daily torpor in the smallest primate, the pygmy mouse lemur ( Microcebus myoxinus ) in Madagascar  

Microsoft Academic Search

Thermoregulation, energetics and patterns of torpor in the pygmy mouse lemur, Microcebus myoxinus, were investigated under natural conditions of photoperiod and temperature in the Kirindy\\/CFPF Forest in western Madagascar.\\u000a M. myoxinus entered torpor spontaneously during the cool dry season. Torpor only occurred on a daily basis and torpor bout duration was\\u000a on average 9.6?h, and ranged from 4.6?h to 19.2?h.

J. Schmid; T. Ruf; G. Heldmaier

2000-01-01

275

Finite strain pattern in Andriamena unit (north-central Madagascar): evidence for late Neoproterozoic–Cambrian thrusting during continental convergence  

Microsoft Academic Search

This paper deals with the late Neoproterozoic–Cambrian tectonic evolution of a part of north-central Madagascar, which is characterized by the occurrence of a mafic-ultramafic sequence (the Andriamena unit) overlying a gneissic-granitic basement. The finite strain pattern has been determined by carrying out a SPOT satellite image analysis, structural mapping of specific areas and kinematic analyses of shear zones. Structural investigations

Philippe Goncalves; Christian Nicollet; Jean-Marc Lardeaux

2003-01-01

276

Indigenous fruit trees of Madagascar: potential components of agroforestry systems to improve human nutrition and restore biological diversity  

Microsoft Academic Search

Biodiversity in Eastern Madagascar is threatened by slash and burn agriculture, which is resulting in species extinction,\\u000a land and soil degradation and rural impoverishment. An ethnobotanical study was undertaken to determine the domestication\\u000a potential of indigenous fruit tree species as components of agroforestry systems. Four major selection criteria were used:\\u000a nutritional and income needs of the population, diversification of the

E. Styger; J. E. M. Rakotoarimanana; R. Rabevohitra; E. C. M. Fernandes

1999-01-01

277

First Isolation and Direct Evidence for the Existence of Large Small-Mammal Reservoirs of Leptospira sp. in Madagascar  

Microsoft Academic Search

BackgroundLeptospirosis has long been a major public health concern in the southwestern Indian Ocean. However, in Madagascar, only a few, old studies have provided indirect serological evidence of the disease in humans or animals.Methodology\\/Principal FindingsWe conducted a large animal study focusing on small-mammal populations. Five field trapping surveys were carried out at five sites, from April 2008 to August 2009.

Soanandrasana Rahelinirina; Albertine Léon; Rudy A. Harstskeerl; Natacha Sertour; Ahmed Ahmed; Claudine Raharimanana; Elisabeth Ferquel; Martine Garnier; Loïc Chartier; Jean-Marc Duplantier; Lila Rahalison; Muriel Cornet; Igor Mokrousov

2010-01-01

278

Population and social dynamics changes in ring-tailed lemur troops at Berenty, Madagascar between 1989–1999  

Microsoft Academic Search

In the present study, we recorded all births, immigrations, deaths, and emigrations for a population of ring-tailed lemurs\\u000a at Berenty Reserve, Madagascar, between September 1989 and August 1999. In September 1989, three troops (C, B, and T) inhabited\\u000a the study area of 14.2 ha. During the 10-year period, eight troop divisions, six evictions of females, and three troop takeovers\\u000a of

Naoki Koyama; Masayuki Nakamichi; Shinichiro Ichinc; Yukio Takahata

2002-01-01

279

Body mass of wild ring-tailed lemurs in Berenty Reserve, Madagascar, with reference to tick infestation: a preliminary analysis  

Microsoft Academic Search

In 1999, we measured the body mass of 101 wild ring-tailed lemurs (Lemur catta) inhabiting the Berenty Reserve, Madagascar. In addition, we counted the number of ticks [Haemaphysalis (Rhipistoma) lemuris Hoogstraal, 1953] infesting their facial skin and external auditory meatuses. For both males and females, the body mass appeared\\u000a to increase until the age of 3 years. With the apparent exception

Naoki Koyama; Mitsuru Aimi; Yoshi Kawamoto; Hirohisa Hirai; Yasuhiro Go; Shinichiro Ichino; Yukio Takahata

2008-01-01

280

Maternal responses to dead and dying infants in wild troops of ring-tailed lemurs at the Berenty Reserve, Madagascar  

Microsoft Academic Search

We describe responses of seven mothers and other troop members to dead and dying infants in several troops of ring-tailed\\u000a lemurs(Lemur catta) at the Berenty Reserve, Madagascar. In contrast to mothers in simian species, ring-tailed lemur mothers rarely carried their\\u000a dying, immobile or dead infants. However, they sniffed, licked, and touched them even after they had died. While the dying

Masayuki Nakamichi; Naoki Koyama; Alison Jolly

1996-01-01

281

Bringing Safe Water to Remote Populations: An Evaluation of a Portable Point-of-Use Intervention in Rural Madagascar  

Microsoft Academic Search

Rural populations disproportionately lack access to improved water supplies. We evaluated a novel scheme that employed community-based sales agents to disseminate the Safe Water System (SWS)—a household-level water chlorination and safe storage intervention—in rural Madagascar. Respondents from 242 households in 4 villages were inter- viewed; all used surface water for drinking water. Respondents from 239 households (99%) had heard of

Pavani Kalluri Ram; Elaine Kelsey; Oliver Rakotomalala; Robert E. Quick

2007-01-01

282

Nesogordonia tricarpellata (Dombeyaceae), a new species from Madagascar that compels modification of the morphological circumscription of the genus  

PubMed Central

Abstract Nesogordonia tricarpellata Skema & Dorr, sp. nov., a new species from southeastern Madagascar, is described and illustrated. It differs from all other species of Nesogordonia Baill. in having 6–9 stamens, 3 staminodes, a 3-carpellate ovary, and a 3-valved capsule. These androecial and gynoecial characters require modification of the long-standing circumscription of the genus. The new species also has the southernmost geographic range of any species in the genus. PMID:22171171

Skema, Cynthia; Dorr, Laurence J.

2011-01-01

283

Régime des eaux souterraines en milieu cristallin altéré: un exemple en zone intertropicale humide d'altitude (Madagascar)  

Microsoft Academic Search

Le régime des eaux souterraines en milieu cristallin altéré (zone intertropicale humide d'altitude de Madagascar) est analysé à grande échelle au cours de trois cycles climatiques successifs: (a) par l'étude hydraulique du milieu (tests par pompages et piézométrie en écoulement naturel); et (b) par des données isotopiques (O et H). Le caractère bicouche de l'aquifère est précisé, en particulier par

J. C. GRILLOT

1992-01-01

284

Density estimates of two endangered nocturnal lemur species from northern Madagascar: new results and a comparison of commonly used methods.  

PubMed

Very little information is known of the recently described Microcebus tavaratra and Lepilemur milanoii in the Daraina region, a restricted area in far northern Madagascar. Since their forest habitat is highly fragmented and expected to undergo significant changes in the future, rapid surveys are essential to determine conservation priorities. Using both distance sampling and capture-recapture methods, we estimated population densities in two forest fragments. Our results are the first known density and population size estimates for both nocturnal species. In parallel, we compare density results from four different approaches, which are widely used to estimate lemur densities and population sizes throughout Madagascar. Four approaches (King, Kelker, Muller and Buckland) are based on transect surveys and distance sampling, and they differ from each other by the way the effective strip width is estimated. The fifth method relies on a capture-mark-recapture (CMR) approach. Overall, we found that the King method produced density estimates that were significantly higher than other methods, suggesting that it generates overestimates and hence overly optimistic estimates of population sizes in endangered species. The other three distance sampling methods provided similar estimates. These estimates were similar to those obtained with the CMR approach when enough recapture data were available. Given that Microcebus species are often trapped for genetic or behavioral studies, our results suggest that existing data can be used to provide estimates of population density for that species across Madagascar. PMID:22311681

Meyler, Samuel Viana; Salmona, Jordi; Ibouroi, Mohamed Thani; Besolo, Aubin; Rasolondraibe, Emmanuel; Radespiel, Ute; Rabarivola, Clément; Chikhi, Lounes

2012-05-01

285

Stable carbon isotope values document how a Late Holocene expansion in grasslands impacted vertebrates in northwestern Madagascar  

NASA Astrophysics Data System (ADS)

Madagascar is home to some of the world's most distinctive plants and animals. Unfortunately, forest loss and habitat degradation has had a dramatic impact on both floral and faunal communities. Here we use carbon isotope values in radiocarbon-dated bones to examine how the vertebrate community at Anjohibe Cave, northwestern Madagascar, responded to a Late Holocene increase in C4 grass abundance. Our data demonstrate that major changes in the vegetation and animal community are recent phenomena at Anjohibe. Extinct lemurs and hippopotamuses were present until ca. 1500 years ago. These taxa relied exclusively on C3 resources. Locally extirpated fauna were present until 300 years ago. The majority of these species also relied on C3 resources. Their presence strongly suggests that the region surrounding the cave was more wooded than it is now, possibly as recently as 300 years ago. All introduced individuals are modern. Rats (Rattus sp.), shrews (Suncus murinus), and the giant frog Hoplobatrachus cf. tigrinus, have remarkably high carbon isotope values, implicating substantial ingestion of C4 foods. It is possible that grass abundance has increased dramatically in the past 100 years. Alternatively, opportunistically granivorous rats and shrews may selectively consume seeds from C4 grasses. In agreement with previous studies, stable isotope data reveal details of vegetation and faunal turnover in Northwestern Madagascar. Grasses have increased, forest dwelling species have vanished, and introduced taxa are exploiting a novel niche.

Crowley, B. E.; Samonds, K.

2012-12-01

286

Assessing flavivirus, lentivirus, and herpesvirus exposure in free-ranging ring-tailed lemurs in southwestern Madagascar.  

PubMed

The ring-tailed lemur (Lemur catta) is an endangered species found in southwestern Madagascar, and understanding infectious disease susceptibility is an essential step towards the preservation of wild and captive lemur populations. Lemurs are primates that are widely dispersed throughout the island of Madagascar and may serve as hosts or reservoirs for zoonotic infections. The aim of this study was to determine the prevalence of antibodies to West Nile virus (WNV), simian immunodeficiency virus (SIV), and herpes simplex virus type 1 (HSV-1) in a population of free-ranging ring-tailed lemur from the Beza Mahafaly Special Reserve, Madagascar. Samples were collected from 50 animals during field capture studies in June and July 2004 and assayed for presence of viral antibodies during the 12 mo following collection. Forty-seven of the 50 lemurs sampled had antibodies against WNV detectable by epitope-blocking enzyme-linked immunosorbent assay (ELISA). In addition, 50 of 50 samples had titers against WNV ranging from 80 to > or = 1,280 using plaque reduction neutralization test (PRNT(90)). Ten lemurs had antibodies against lentiviral antigens as determined by Western blot analysis. None of the lemurs had antibodies against HSV-1 using ELISA. PMID:17347392

Sondgeroth, Kerry; Blitvich, Brad; Blair, Carol; Terwee, Julie; Junge, Randall; Sauther, Michelle; VandeWoude, Sue

2007-01-01

287

The Madagascar hissing cockroach as a novel surrogate host for Burkholderia pseudomallei, B. mallei and B. thailandensis  

PubMed Central

Background Burkholderia pseudomallei and Burkholderia mallei are gram-negative pathogens responsible for the diseases melioidosis and glanders, respectively. Both species cause disease in humans and animals and have been designated as category B select agents by the Centers for Disease Control and Prevention (CDC). Burkholderia thailandensis is a closely related bacterium that is generally considered avirulent for humans. While it can cause disease in rodents, the B. thailandensis 50% lethal dose (LD50) is typically???104-fold higher than the B. pseudomallei and B. mallei LD50 in mammalian models of infection. Here we describe an alternative to mammalian hosts in the study of virulence and host-pathogen interactions of these Burkholderia species. Results Madagascar hissing cockroaches (MH cockroaches) possess a number of qualities that make them desirable for use as a surrogate host, including ease of breeding, ease of handling, a competent innate immune system, and the ability to survive at 37°C. MH cockroaches were highly susceptible to infection with B. pseudomallei, B. mallei and B. thailandensis and the LD50 was <10 colony-forming units (cfu) for all three species. In comparison, the LD50 for Escherichia coli in MH cockroaches was >105?cfu. B. pseudomallei, B. mallei, and B. thailandensis cluster 1 type VI secretion system (T6SS-1) mutants were all attenuated in MH cockroaches, which is consistent with previous virulence studies conducted in rodents. B. pseudomallei mutants deficient in the other five T6SS gene clusters, T6SS-2 through T6SS-6, were virulent in both MH cockroaches and hamsters. Hemocytes obtained from MH cockroaches infected with B. pseudomallei harbored numerous intracellular bacteria, suggesting that this facultative intracellular pathogen can survive and replicate inside of MH cockroach phagocytic cells. The hemolymph extracted from these MH cockroaches also contained multinuclear giant cells (MNGCs) with intracellular B. pseudomallei, which indicates that infected hemocytes can fuse while flowing through the insect’s open circulatory system in vivo. Conclusions The results demonstrate that MH cockroaches are an attractive alternative to mammals to study host-pathogen interactions and may allow the identification of new Burkholderia virulence determinants. The importance of T6SS-1 as a virulence factor in MH cockroaches and rodents suggests that the primary role of this secretion system is to target evasion of the innate immune system. PMID:22892068

2012-01-01

288

Campylobacter infection in a cohort of rural children in Moramanga, Madagascar  

PubMed Central

Background Campylobacter infection is the most common cause of bacterial gastroenteritis in developing countries, including Madagascar. Reports of pathogenicity have not been consistent and repeated exposures over time seem to lead to the development of protective immunity in developing areas. We conducted this study to support evidence for these hypotheses by exploring the association between infection and age, the reoccurrence of infection and the pathogenicity of Campylobacter. Methods We carried out a community-based longitudinal study of children under the age of 24 months in two rural villages in Moramanga, Madagascar. Children were visited twice a week and a stool specimen was collected in cases of diarrhoea. Stools specimens were collected bimonthly from all children enrolled, regardless of symptoms. Children were followed-up until the age of 36 months. Results Between January 2010 and May 31st 2012, 508 children were included in the cohort. We detected 319 episodes of Campylobacter infection in total, and 43.3% (n?=?220) of the children had at least one episode of intestinal Campylobacter infection. The rate of Campylobacter isolation from stool specimens was 9.3%. The annual incidence rate for symptomatic Campylobacter infection was 0.05 episodes/child. The probability of Campylobacter infection was highest between the ages of six and 23 months. Taking children under six months of age as the reference group, the age-specific odds ratio for the association was 5.0 (95% CI: 2.9-8.6) for children aged six to 11 months, 5.7 (95% CI: 3.3-10.0) for children aged 12 to 17 months and 3.3 (95% CI: 1.8-5.8) for children aged 18 to 23 months. A second episode of infection occurred 63 days after the first episode in children with primary infections, and after 137 days in children with multiple infections (p?

2014-01-01

289

A new microhylid frog, genus Rhombophryne, from northeastern Madagascar, and a re-description of R. serratopalpebrosa using micro-computed tomography.  

PubMed

The rainforests of the Marojejy massif in northern Madagascar are a well-known hotspot of amphibian species diversity and endemism. In the present paper, we re-describe Rhombophryne serratopalpebrosa (Guibé 1975), a cophyline microhylid frog from high altitude on this massif, based on a re-examination of its holotype, and describe Rhombophryne vaventy sp. nov. using characters of external morphology and osteology, illustrated by pdf-embedded comparative 3D models of their skeletons. Rhombophryne serratopalpebrosa differs from R. vaventy sp. nov. by smaller size (28 mm snout-vent length vs. 52.9 mm), skin texture (granular vs. rough and tubercular skin respectively), supratympanic fold shape (strong, long and straight reaching the eye vs. curved and not extending anteriorly beyond the tympanum), relative tympanum diameter (78% vs. 41% of eye diameter), shape of the postchoanal prevomerine palate, shape of the footplate of the columella, length of prepollex, and by other subtle osteological features. Morphological comparisons suggest that a specimen from Ambolokopatrika assigned to R. serratopalpebrosa in previous genetic studies might belong to yet another undescribed species, closely related to R. vaventy sp. nov., whereas DNA sequences of the topotypic R. serratopalpebrosa remain unknown. We therefore emphasise the need for collecting additional material from high altitudes of the Marojejy massif to understand the systematics, as well as the natural history, of this poorly known species. For the new species described herein, we propose a Red List threat status of Vulnerable, in line with other Marojejy endemics from a similar altitude.  PMID:25283290

Scherz, Mark D; Ruthensteiner, Bernhard; Vences, Miguel; Glaw, Frank

2014-01-01

290

Providing family planning services to remote communities in areas of high biodiversity through a Population-Health-Environment programme in Madagascar.  

PubMed

Population-Health-Environment (PHE) is an interdisciplinary model of programme design which recognises the complex interconnections between people, their health and their environment. PHE responds holistically to the challenges faced by ecosystems and the communities dependent on them, with thematically distinct but interconnected work strands sharing the same infrastructure, resources and goals. This has been shown to achieve better outcomes than tackling health and environmental issues in isolation. This paper shows how PHE programme design has been used by Blue Ventures for providing family planning services in a remote, biodiverse coastal region in southwest Madagascar. The PHE programme has integrated family planning services into a pre-existing, community-based conservation programme, aided by the established infrastructure and good community relations developed by the conservation workers. Implementation of the programme has led to a strong uptake of family planning services, and couples in the region are now able to make their own family planning choices. Successes and challenges of the programme are discussed. PMID:24908460

Mohan, Vik; Shellard, Tess

2014-05-01

291

Air pollution studies in terms of PM2.5, PM2.5-10, PM10, lead and black carbon in urban areas of Antananarivo - Madagascar  

E-print Network

Atmospheric aerosols or particulate matters are chemically complex and dynamic mixtures of solid and liquid particles. Sources of particulate matters include both natural and anthropogenic processes. The present work consists in determining the concentrations of existing elements in the aerosols collected in Andravoahangy and in Ambodin'Isotry in Antananarivo city (Madagascar). The size distribution of these elements and their main sources are also studied. The Total Reflection X-Ray Fluorescence spectrometer is used for the qualitative and quantitative analyses. The results show that the concentrations of the airborne particulate matters PM2.5-10 are higher than those of PM2.5. The identified elements in the aerosol samples are Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr and Pb. The average concentrations of these elements are also higher in the coarse particles than in the fine particles. The calculation of the enrichment factors by Mason's model shows that Cr, Ni, Cu, Zn, Br and Pb are of anthropogenic origins. The...

Rasoazanany, E O; Ravoson, H N; Andriambololona, Raoelina; Randriamanivo, L V; Ramaherison, H; Ahmed, H; Harinoely, M

2012-01-01

292

Aye-aye (Daubentonia madagascariensis) feeding strategies at Ranomafana National Park, Madagascar: an indirect sampling method.  

PubMed

In this research, we focused on aye-aye populations in Ranomafana National Park, Madagascar. From August to December 2008, we tested how aye-aye feeding was influenced by presence/absence of both fruiting and non-fruiting Canarium trees. Deadwood feeding traces were used as a proxy for evidence of Canarium feeding. We enumerated deadwood feeding traces in 20 locations, 10 with Canarium, 10 without. Each location contained two transects (80 m L × 20 m W) for a total area of 5.6 ha. Feeding trace results for Canarium locations compared to non-Canarium locations were not significant (Z = -1.926, p = 0.083); however, feeding trace results were significant when comparing fruiting and non-fruiting Canarium locations (Z = -2.417, p = 0.016). These results highlight the importance of Canarium in the diet of aye-ayes and demonstrate how the distribution of this resource may influence the foraging behavior of aye-ayes. PMID:22627178

Sefczek, Timothy M; Farris, Zach J; Wright, Patricia C

2012-01-01

293

Extreme vulnerability of smallholder farmers to agricultural risks and climate change in Madagascar.  

PubMed

Across the tropics, smallholder farmers already face numerous risks to agricultural production. Climate change is expected to disproportionately affect smallholder farmers and make their livelihoods even more precarious; however, there is limited information on their overall vulnerability and adaptation needs. We conducted surveys of 600 households in Madagascar to characterize the vulnerability of smallholder farmers, identify how farmers cope with risks and explore what strategies are needed to help them adapt to climate change. Malagasy farmers are particularly vulnerable to any shocks to their agricultural system owing to their high dependence on agriculture for their livelihoods, chronic food insecurity, physical isolation and lack of access to formal safety nets. Farmers are frequently exposed to pest and disease outbreaks and extreme weather events (particularly cyclones), which cause significant crop and income losses and exacerbate food insecurity. Although farmers use a variety of risk-coping strategies, these are insufficient to prevent them from remaining food insecure. Few farmers have adjusted their farming strategies in response to climate change, owing to limited resources and capacity. Urgent technical, financial and institutional support is needed to improve the agricultural production and food security of Malagasy farmers and make their livelihoods resilient to climate change. PMID:24535397

Harvey, Celia A; Rakotobe, Zo Lalaina; Rao, Nalini S; Dave, Radhika; Razafimahatratra, Hery; Rabarijohn, Rivo Hasinandrianina; Rajaofara, Haingo; Mackinnon, James L

2014-04-01

294

Factors associated with coverage and usage of long-lasting insecticidal nets in madagascar.  

PubMed

In October 2007, long-lasting insecticidal nets (LLINs) were distributed in 59 of the 111 districts in Madagascar as part of a nationwide child survival campaign. A community-based cross-sectional survey was conducted six months post-campaign to evaluate net ownership, use and equity. Here, we examined the effects of socioeconomic factors on LLIN ownership and usage in districts with and without net distribution during the campaign. Our data demonstrated that in districts with LLIN distribution, LLIN ownership was similar across all wealth groups in households with at least one child under the age of five years (90.5% versus 88.6%); in districts without net distribution, 57.8% of households in the poorest tertile compared to 90.1% of households in the least poor tertile owned at least one LLIN. In contrast, in LLIN-owning households, both in districts with and without net distribution, higher socio-economic status was not associated with use among children under five years. These findings suggest that socio-economic status contributes to the household net ownership but once a household owns a net, socio-economic status is not associated with net use. PMID:20309420

Thawani, Neeta; Kulkarni, Manisha A; Sohani, Salim

2009-01-01

295

Factors Associated with Coverage and Usage of Long-Lasting Insecticidal Nets in Madagascar  

PubMed Central

In October 2007, long-lasting insecticidal nets (LLINs) were distributed in 59 of the 111 districts in Madagascar as part of a nationwide child survival campaign. A community-based cross-sectional survey was conducted six months post-campaign to evaluate net ownership, use and equity. Here, we examined the effects of socioeconomic factors on LLIN ownership and usage in districts with and without net distribution during the campaign. Our data demonstrated that in districts with LLIN distribution, LLIN ownership was similar across all wealth groups in households with at least one child under the age of five years (90.5% versus 88.6%); in districts without net distribution, 57.8% of households in the poorest tertile compared to 90.1% of households in the least poor tertile owned at least one LLIN. In contrast, in LLIN-owning households, both in districts with and without net distribution, higher socio-economic status was not associated with use among children under five years. These findings suggest that socio-economic status contributes to the household net ownership but once a household owns a net, socio-economic status is not associated with net use. PMID:20309420

Thawani, Neeta; Kulkarni, Manisha A.; Sohani, Salim

2009-01-01

296

Long-term changes in dominance ranks among ring-tailed lemurs at Berenty Reserve, Madagascar.  

PubMed

A study was conducted between 1989 and 2001 to monitor changes in the dominance ranks among adult ring-tailed lemurs (Lemur catta) at Berenty Reserve, Madagascar. Adult females were observed to be dominant over adult males. Their rank fluctuated greatly. However, in some troops, female rank orders were fairly stable over a period of several years. In general, male ranks were more unstable than female ranks. Most young females aged 3 years occupied the lowest ranks among adult females. However, several were also observed to have attained relatively higher ranks, placing them right beneath their high-ranking mothers; this suggested the existence of "dependent ranks". Mothers were dominant over their daughters. Similarly, older sisters were usually dominant over younger sisters. The mean duration of alpha status for females was 1.95 years, although considerable variation was observed in the duration of the alpha status (1-5 or more years). Most young males aged 3 years initially occupied the lowest ranks in their natal troops, and then they migrated to non-natal troops around the age of 4 years. They ascended in rank between the ages of 4 and 6 years, although there was considerable variation in the acquirement of high rank. The mean duration of alpha status for males was 2.2 years. Larger males were observed to occupy higher ranks. Occasionally, both males and females showed intense aggression (i.e., targeting aggression) towards others. PMID:16142423

Koyama, Naoki; Ichino, Shinichiro; Nakamichi, Masayuki; Takahata, Yukio

2005-10-01

297

[Eradication of poliomyelitis and emergence of pathogenic vaccine-derived polioviruses: from Madagascar to Cameroon].  

PubMed

The oral poliovaccine, a live vaccine made of attenuated poliovirus strains, is the main tool of the vaccination campaigns organised for eradicating poliomyelitis. these campaigns had led to the decline and, thereafter, to the disappearance of wild poliovirus strains of the three serotypes (1-3) in most parts of the world. However, when the poliovaccine coverage becomes too low, vaccine polioviruses can circulate in insufficiently immunized populations and become then pathogenic by mutations and genetic recombination with other enteroviruses of the same species, in particular some coxsackievirus A. These mutated and recombinant vaccine strains have been implicated in several epidemics of paralytic poliomyelitis. Two polio outbreaks associated with these pathogenic circulating vaccine-derived poliovirus (cVDPV) occurred in 2001-2002 and 2005 in the South of Madagascar where vaccine coverage was low. These cVDPV, of serotype 2 or 3, were isolated from paralyzed children and some of their healthy contacts. Other cVDPV were isolated in the same region from healthy children in 2011, indicating that these viruses were circulating again. Vaccination campaigns could stop the outbreaks in 2002 and 2005, and most probably prevent another one in 2011. Therefore, the genetic plasticity of poliovaccine strains that threatens the benefit of vaccination campaigns is the target of an accurate surveillance and an important theme of studies in the virology laboratories of the Institut Pasteur international network. PMID:24280508

Delpeyroux, Francis; Colbère-Garapin, Florence; Razafindratsimandresy, Richter; Sadeuh-Mba, Serge; Joffret, Marie-Line; Rousset, Dominique; Blondel, Bruno

2013-11-01

298

Seroprevalence of Antibodies against Chikungunya, Dengue, and Rift Valley Fever Viruses after Febrile Illness Outbreak, Madagascar  

PubMed Central

In October 2009, two–3 months after an outbreak of a febrile disease with joint pain on the eastern coast of Madagascar, we assessed serologic markers for chikungunya virus (CHIKV), dengue virus (DENV), and Rift Valley fever virus (RVFV) in 1,244 pregnant women at 6 locations. In 2 eastern coast towns, IgG seroprevalence against CHIKV was 45% and 23%; IgM seroprevalence was 28% and 5%. IgG seroprevalence against DENV was 17% and 11%. No anti-DENV IgM was detected. At 4 locations, 450–1,300 m high, IgG seroprevalence against CHIKV was 0%–3%, suggesting CHIKV had not spread to higher inland-altitudes. Four women had IgG against RVFV, probably antibodies from a 2008 epidemic. Most (78%) women from coastal locations with CHIKV-specific IgG reported joint pain and stiffness; 21% reported no symptoms. CHIKV infection was significantly associated with high bodyweight. The outbreak was an isolated CHIKV epidemic without relevant DENV co-transmission. PMID:23092548

Girmann, Mirko; Randriamampionona, Njary; Bialonski, Alexandra; Maus, Deborah; Krefis, Anne Caroline; Njarasoa, Christine; Rajanalison, Jeanne Fleury; Ramandrisoa, Herly Daniel; Randriarison, Maurice Lucien; May, Jurgen; Schmidt-Chanasit, Jonas; Rakotozandrindrainy, Raphael

2012-01-01

299

Seroprevalence of antibodies against Chikungunya, Dengue, and Rift Valley fever viruses after febrile illness outbreak, Madagascar.  

PubMed

In October 2009, two-3 months after an outbreak of a febrile disease with joint pain on the eastern coast of Madagascar, we assessed serologic markers for chikungunya virus (CHIKV), dengue virus (DENV), and Rift Valley fever virus (RVFV) in 1,244 pregnant women at 6 locations. In 2 eastern coast towns, IgG seroprevalence against CHIKV was 45% and 23%; IgM seroprevalence was 28% and 5%. IgG seroprevalence against DENV was 17% and 11%. No anti-DENV IgM was detected. At 4 locations, 450-1,300 m high, IgG seroprevalence against CHIKV was 0%-3%, suggesting CHIKV had not spread to higher inland-altitudes. Four women had IgG against RVFV, probably antibodies from a 2008 epidemic. Most (78%) women from coastal locations with CHIKV-specific IgG reported joint pain and stiffness; 21% reported no symptoms. CHIKV infection was significantly associated with high bodyweight. The outbreak was an isolated CHIKV epidemic without relevant DENV co-transmission. PMID:23092548

Schwarz, Norbert G; Girmann, Mirko; Randriamampionona, Njary; Bialonski, Alexandra; Maus, Deborah; Krefis, Anne Caroline; Njarasoa, Christine; Rajanalison, Jeanne Fleury; Ramandrisoa, Herly Daniel; Randriarison, Maurice Lucien; May, Jürgen; Schmidt-Chanasit, Jonas; Rakotozandrindrainy, Raphael

2012-11-01

300

Polyphase Neoproterozoic orogenesis within the east Africa- Antarctica orogenic belt in central and northern Madagascar  

USGS Publications Warehouse

Our recent geological survey of the basement of central and northern Madagascar allowed us to re-evaluate the evolution of this part of the East Africa-Antarctica Orogen (EAAO). Five crustal domains are recognized, characterized by distinctive lithologies and histories of sedimentation, magmatism, deformation and metamorphism, and separated by tectonic and/or unconformable contacts. Four consist largely of Archaean metamorphic rocks (Antongil, Masora and Antananarivo Cratons, Tsaratanana Complex). The fifth (Bemarivo Belt) comprises Proterozoic meta-igneous rocks. The older rocks were intruded by plutonic suites at c. 1000 Ma, 820-760 Ma, 630-595 Ma and 560-520 Ma. The evolution of the four Archaean domains and their boundaries remains contentious, with two end-member interpretations evaluated: (1) all five crustal domains are separate tectonic elements, juxtaposed along Neoproterozoic sutures and (2) the four Archaean domains are segments of an older Archaean craton, which was sutured against the Bemarivo Belt in the Neoproterozoic. Rodinia fragmented during the early Neoproterozoic with intracratonic rifts that sometimes developed into oceanic basins. Subsequent Mid- Neoproterozoic collision of smaller cratonic blocks was followed by renewed extension and magmatism. The global 'Terminal Pan-African' event (560-490 Ma) finally stitched together the Mid-Neoproterozoic cratons to form Gondwana. ?? The Geological Society of London 2011.

Key, R.M.; Pitfield, P.E.J.; Thomas, R.J.; Goodenough, K.M.; Waele, D.; Schofield, D.I.; Bauer, W.; Horstwood, M.S.A.; Styles, M.T.; Conrad, J.; Encarnacion, J.; Lidke, D.J.; O'connor, E. A.; Potter, C.; Smith, R.A.; Walsh, G.J.; Ralison, A.V.; Randriamananjara, T.; Rafahatelo, J.-M.; Rabarimanana, M.

2011-01-01

301

Post-collisional magmatism in the central East African Orogen: The Maevarano Suite of north Madagascar  

USGS Publications Warehouse

Late tectonic, post-collisional granite suites are a feature of many parts of the Late Neoproterozoic to Cambrian East African Orogen (EAO), where they are generally attributed to late extensional collapse of the orogen, accompanied by high heat flow and asthenospheric uprise. The Maevarano Suite comprises voluminous plutons which were emplaced in some of the tectonostratigraphic terranes of northern Madagascar, in the central part of the EAO, following collision and assembly during a major orogeny at ca. 550 Ma. The suite comprises three main magmatic phases: a minor early phase of foliated gabbros, quartz diorites, and granodiorites; a main phase of large batholiths of porphyritic granitoids and charnockites; and a late phase of small-scale plutons and sheets of monzonite, syenite, leucogranite and microgranite. The main phase intrusions tend to be massive, but with variably foliated margins. New U-Pb SHRIMP zircon data show that the whole suite was emplaced between ca. 537 and 522 Ma. Geochemically, all the rocks of the suite are enriched in the LILE, especially K, and the LREE, but are relatively depleted in Nb, Ta and the HREE. These characteristics are typical of post-collisional granitoids in the EAO and many other orogenic belts. It is proposed that the Maevarano Suite magmas were derived by melting of sub-continental lithospheric mantle that had been enriched in the LILE during earlier subduction events. The melting occurred during lithospheric delamination, which was associated with extensional collapse of the East African Orogen. ?? 2009 Natural Environment Research Council.

Goodenough, K.M.; Thomas, R.J.; De Waele, B.; Key, R.M.; Schofield, D.I.; Bauer, W.; Tucker, R.D.; Rafahatelo, J.-M.; Rabarimanana, M.; Ralison, A.V.; Randriamananjara, T.

2010-01-01

302

Bark essential oil of Cedrelopsis grevei from Madagascar: investigation of steam-distillation conditions.  

PubMed

The effect of the distillation time on the yield and chemical composition of the bark essential oil of Cedrelopsis grevei Baill. was investigated. Distillation kinetics were determined for three batches of bark sampled from two sites, i.e., Itampolo (batches IT1 and IT2) and Salary (SAL), located in a region in the south of Madagascar with characteristically large populations of C. grevei. The bark samples were subjected to steam distillation, and the essential oil was collected at 3-h intervals. The total yield (calculated after 14?h of distillation) varied from 0.9 to 1.7%, according to the batch tested. Moreover, the essential oils obtained were characterized by GC-FID and GC/MS analyses. During the course of the distillation, the relative percentages of the most volatile components (monoterpenes and sesquiterpene hydrocarbons) diminished progressively, whereas the least volatile ones (oxygenated derivatives) increased at a consistent rate. Principal component analysis (PCA) and agglomerative hierarchical clustering analysis (AHC) of the results, performed on 13 principal components, allowed distinguishing three chemical groups, corresponding to the three batches, irrespective of the distillation time. This indicated that the chemical variability currently observed with commercial samples is not mainly linked to the experimental conditions of the extraction process, as the distillation time did not significantly alter the chemical composition of the essential oils. PMID:24591320

Rakotobe, Miarantsoa; Menut, Chantal; Andrianoelisoa, Hanitriniaina Sahondra; Rahajanirina, Voninavoko; Tsy, Jean Michel Leong Pock; Rakotoarimanana, Vonjison; Ramavovololona, Perle; Danthu, Pascal

2014-02-01

303

Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa) and Foleyella furcata (Nematoda) in wild endemic reptiles from Madagascar  

PubMed Central

Madagascar is one of the world’s top twelve “megadiversity” hot spots hosting unique and threatened flora and fauna. Parasites are a major component of biodiversity but remain largely uncharacterized in wildlife. In this study we combine microscopic and molecular assessment of hemoparasites in endemic reptile species from Madagascar. We detected three distinct parasites: the apicomplexans Hepatozoon and Sarcocystis, and filarial nematodes. The prevalence and intensity of these apicomplexans were low overall, while microfilarial infections in chameleons were relatively high. We detected mixed infections of two Hepatozoon haplotypes in Madagascarophis colubrinus, and of Hepatozoon and microfilariae in a Furcifer sp. Phylogenetic analyses of Hepatozoon showed evidence of prey-predator transmission, with identical sequences found in the snakes M. colubrinus and Ithycyphus oursi, and their prey Furcifer sp. Based on previous studies regarding the life cycle of Hepatozoon domerguei Landau, Chabaud, Michel, and Brygoo, 1970 in these hosts and due to their morphological similarity, we propose that this Hepatozoon haplotype is Hepatozoon domerguei. Future studies, including the examination of invertebrate hosts, are needed to verify this preliminary taxonomic identification. A distinct hemogregarine haplotype was found in Oplurus sp., which displayed morphologically different gametocytes, some of which were apparently inside leukocytes. The Sarcocystis identified from Tracheloptychus petersi was identical to that reported in a North African snake, indicating that the same lineage is found in geographically distinct regions. By combining morphological and genetic information, Foleyella furcata (Linstow, 1899) filarial nematodes were identified in several Furcifer chameleons. This study provides insights into the distribution, diversity and host-parasite interactions of hemoparasites in wild reptile populations from Madagascar. PMID:25224723

Maia, Joao P.; Crottini, Angelica; Harris, David James

2014-01-01

304

New species from the Galoka and Kalabenono massifs: two unknown and severely threatened mountainous areas in NW Madagascar  

PubMed Central

The Galoka mountain chain, comprising principally the Galoka and Kalabenono massifs, situated at the northern edge of the Sambirano Region in NW Madagascar is an area that was virtually unknown botanically. It was visited three times between 2005 and 2007 as part of a floristic inventory. Both massifs contain the last remaining primary forests in the Galoka chain, which extends parallel to the coastline from South of Ambilobe to North of Ambanja. Several new species have been discovered amongst the collections, eight of which are described here. PMID:21857767

Callmander, Martin W.; Rakotovao, Charles; Razafitsalama, Jeremi; Phillipson, Peter B.; Buerki, Sven; Hong-Wa, Cynthia; Rakotoarivelo, Nivo; Andriambololonera, Sylvie; Koopman, Margaret M.; Johnson, David M.; Deroin, Thierry; Ravoahangy, Andriamandranto; Solo, Serge; Labat, Jean-Noel; Lowry, Porter P.

2011-01-01

305

Cryogenian (˜830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar?  

NASA Astrophysics Data System (ADS)

The northern Madurai Block, southern India, lies directly south of, and partly deformed by, the Palghat-Cauvery Shear Zone System (PCSS) - a potential suture of the Neoproterozoic Mozambique Ocean. The Kadavur gabbro-anorthosite complex lies south of the PCSS, in the northern Madurai Block, and crystallized at 829 ± 14 Ma (LA-ICPMS zircon data) in a supra-subduction zone setting. The complex contains zircon ?Hf(t) values of -12.5 to -8.6 that represent Palaeoproterozoic T(DM) model ages (2.3-2.5 Ga). These broadly agree with a whole rock neodymium T(DM) model age of 2287 Ma. Oxygen isotope ? 18O ratios range from 5.82‰ and 6.74‰. The parental magma for the gabbro-anorthosites are interpreted to be derived from a juvenile Neoproterozoic mantle contaminated by Mesoarchaean igneous infra-crustal sources. The gabbro-anorthosites intrude quartzites with dominantly Palaeoproterozoic detrital zircons that contain Neoarchaean and Mesoarchaean hafnium model ages. These quartzite zircons contain metamorphic rims that yield an age of 843 ± 23 Ma demonstrating the autochthonous nature of the gabbro-anorthosite complex. Later felsic magmatism is recorded by the 766 ± 8 Ma crystallisation age of the protolith of a felsic gneiss. Cryogenian magmatism in the Madurai Block is interpreted to form part of an extensive arc magmatic province within the southern East African Orogen that can be traced from central Madagascar, through southern India to the Wanni Complex of Sri Lanka. This province is interpreted to have formed above a south/west dipping subduction system as the Mozambique Ocean was subducted under the Neoproterozoic continent Azania.

Teale, William; Collins, Alan S.; Foden, John; Payne, Justin L.; Plavsa, Diana; Chetty, T. R. K.; Santosh, M.; Fanning, Mark

2011-08-01

306

Study on the movement of Rattus rattus and evaluation of the plague dispersion in Madagascar.  

PubMed

Plague affects mainly the rural areas in the central highlands of Madagascar. Rattus rattus is the main rodent host of Yersinia pestis in these localities. Since the introduction of plague, endemic foci have continued to expand, and spatiotemporal variability in the distribution of human plague has been observed. To assess the movements of R. rattus and evaluate the risk of dispersion of the disease, a field study at the scale of the habitats (houses, hedges of sisals, and rice fields) in the plague villages was carried out during high and low seasons of plague transmission to humans. The systemic oral marker Rhodamine B was used to follow rats' movements. Baits were placed in different habitats, and trapping success was carried out once a month for 3 months after the bait distribution. Plague indicators (reservoirs' abundance, flea index, Y. pestis prevalence in fleas, and Y. pestis antibody prevalence in rats) were determined. The highest abundance of rats and marking efficiency were observed in the sisal hedges and the rice fields. Marked rats were captured most commonly near the points where baits were initially placed. The main movements of rats were observed between the houses and sisal hedges. Major differences were observed between the seasons of high and low plague transmission. During the season of low plague transmission, rats were more abundant in the sisal hedges and rice fields, with rats moving from the houses to the rice fields. During the high plague transmission season, rats moved from the hedges of sisal to the rice fields. Important indicators of vector abundance and plague transmission were higher during the high plague transmission season. The three study habitats were the risk areas for plague transmission, but the risk appeared highest in the houses and sisals. Rats' movements according to the season were likely directed by the availability of food. PMID:20158335

Rahelinirina, Soanandrasana; Duplantier, Jean Marc; Ratovonjato, Jocelyn; Ramilijaona, Olga; Ratsimba, Mamy; Rahalison, Lila

2010-01-01

307

The importance of taboos and social norms to conservation in Madagascar.  

PubMed

Informal institutions governing the use of wild species are present in many societies. A system of prohibitions known as fady is central to Malagasy culture. We examined whether fady that relate to the use of natural resources in the eastern rainforests of Madagascar play an important conservation role. Prohibitions ranged from strict taboos in which a species or area was forbidden by the ancestors to social norms that concerned acceptable behavior when harvesting wild species. Strict taboos offered real protection to threatened species, such as the lemur Propithecus edwardsi and the carnivore Cryptoprocta ferox. Taboos also reduced pressure on some economically important endemic species by preventing their sale or limiting the harvest season. Despite their value for conservation, the taboos did not appear to originate from attempts to sustainably manage resources. Nevertheless, social norms, in which the sanction was social disapproval rather than supernatural retribution, encouraged sustainable harvesting practices for tenrecs (Tenrec ecudatus) and pandans (Pandanus spp.). Unfortunately, the social norms concerning methods of harvesting pandans appeared to be breaking down in villages surrounding Ranomafana National Park, and we suggest that the imposition of external conservation rules is weakening traditional management. Informal institutions are important to conservation because they suggest ways of improving cultural understanding and conservation communication. Food taboos influence societal preferences, which affect the wider demand for a species. Most important, where capacity to enforce external conservation rules is limited, informal institutions may provide the only effective regulations. Informal institutions should receive greater attention from conservation biologists so that local people's conservation roles can be acknowledged fairly and so that potential synergies with conservation objectives can be realized. PMID:18616743

Jones, Julia P G; Andriamarovololona, Mijasoa M; Hockley, Neal

2008-08-01

308

Patterns of Loss and Regeneration of Tropical Dry Forest in Madagascar: The Social Institutional Context  

PubMed Central

Loss of tropical forests and changes in land-use/land-cover are of growing concern worldwide. Although knowledge exists about the institutional context in which tropical forest loss is embedded, little is known about the role of social institutions in influencing regeneration of tropical forests. In the present study we used Landsat images from southern Madagascar from three different years (1984, 1993 and 2000) and covering 5500 km2, and made a time-series analysis of three distinct large-scale patterns: 1) loss of forest cover, 2) increased forest cover, and 3) stable forest cover. Institutional characteristics underlying these three patterns were analyzed, testing the hypothesis that forest cover change is a function of strength and enforcement of local social institutions. The results showed a minor decrease of 7% total forest cover in the study area during the whole period 1984–2000, but an overall net increase of 4% during the period 1993–2000. The highest loss of forest cover occurred in a low human population density area with long distances to markets, while a stable forest cover occurred in the area with highest population density and good market access. Analyses of institutions revealed that loss of forest cover occurred mainly in areas characterized by insecure property rights, while areas with well-defined property rights showed either regenerating or stable forest cover. The results thus corroborate our hypothesis. The large-scale spontaneous regeneration dominated by native endemic species appears to be a result of a combination of changes in precipitation, migration and decreased human population and livestock grazing pressure, but under conditions of maintained and well-defined property rights. Our study emphasizes the large capacity of a semi-arid system to spontaneously regenerate, triggered by decreased pressures, but where existing social institutions mitigate other drivers of deforestation and alternative land-use. PMID:17476324

Elmqvist, Thomas; Pyykönen, Markku; Tengö, Maria; Rakotondrasoa, Fanambinantsoa; Rabakonandrianina, Elisabeth; Radimilahy, Chantal

2007-01-01

309

Phylogenomics and taxonomy of Lecomtelleae (Poaceae), an isolated panicoid lineage from Madagascar  

PubMed Central

Background and Aims An accurate characterization of biodiversity requires analyses of DNA sequences in addition to classical morphological descriptions. New methods based on high-throughput sequencing may allow investigation of specimens with a large set of genetic markers to infer their evolutionary history. In the grass family, the phylogenetic position of the monotypic genus Lecomtella, a rare bamboo-like endemic from Madagascar, has never been appropriately evaluated. Until now its taxonomic treatment has remained controversial, indicating the need for re-evaluation based on a combination of molecular and morphological data. Methods The phylogenetic position of Lecomtella in Poaceae was evaluated based on sequences from the nuclear and plastid genomes generated by next-generation sequencing (NGS). In addition, a detailed morphological description of L. madagascariensis was produced, and its distribution and habit were investigated in order to assess its conservation status. Key Results The complete plastid sequence, a ribosomal DNA unit and fragments of low-copy nuclear genes (phyB and ppc) were obtained. All phylogenetic analyses place Lecomtella as an isolated member of the core panicoids, which last shared a common ancestor with other species >20 million years ago. Although Lecomtella exhibits morphological characters typical of Panicoideae, an unusual combination of traits supports its treatment as a separate group. Conclusions The study showed that NGS can be used to generate abundant phylogenetic information rapidly, opening new avenues for grass phylogenetics. These data clearly showed that Lecomtella forms an isolated lineage, which, in combination with its morphological peculiarities, justifies its treatment as a separate tribe: Lecomtelleae. New descriptions of the tribe, genus and species are presented with a typification, a distribution map and an IUCN conservation assessment. PMID:23985988

Besnard, Guillaume; Christin, Pascal-Antoine; Male, Pierre-Jean G.; Coissac, Eric; Ralimanana, Helene; Vorontsova, Maria S.

2013-01-01

310

Renaud Paulian et le programme du CNRS sur les hautes montagnes à Madagascar: étage vs domaine  

PubMed Central

Résumé Le programme intitulé « Étude des écosystémes montagnards dans la région malgache» (RCP 225/CNRS; responsable: Recteur Renaud Paulian) avait pour ambition de dégager leurs caractères généraux, l'origine des éléments constitutifs et de tester la validité d'un Domaine malgache des Hautes Montagnes proposé par Humbert dès 1951. De 1970 à 1973, trois campagnes (Andringitra; Chaînes anosyennes et Ankaratra; Itremo, Ibity et Marojejy) ont permis une caractérisation écologique des milieux particuliers ainsi que des analyses de systématique sur certains taxa connus pour leur intérêt biogéographique. La succession altitudinale des formations végétales, définies par des critères physionomiques et structuraux, est précisée par massif. Le dernier étage caractérisé par le fourré éricoïde et ses groupements associés ne correspond pas à l'Étage des Hautes Montagnes de l'Est africain. Des groupes de la faune (invertébrés hexapodes: Collemboles et Dermaptères) indiquent une disjonction entre les massifs du Nord (Tsaratanana, Marojejy), ceux du Centre et du Sud; des éléments de la flore (Pandanaceae, Araliaceae, Asteraceae) sont en cours d'analyse dans le même sens. Le Domaine des Hautes montagnes à Madagascar est une réalité écologique mais ne peut être défini floristiquement; chaque massif montagneux est une entité phytogéographique d'étages de végétation interdépendants inclus dans les différents Sous-Domaines du Centre. Les groupes peu mobiles de la faune indiquent globalement une dépendance trophique et bioclimatique (effet tampon du climat intraforestier) vis-à-vis des étages de végétation, mais peuvent réagir à des microclimats locaux par des décalages à leurs limites. PMID:21731422

Guillaumet, Jean-Louis; Betsch, Jean-Marie; Callmander, Martin W.

2011-01-01

311

Symbolic capital and health: the case of women's sex work in Antananarivo, Madagascar.  

PubMed

Public health research on sex work has been criticized both for representing sex work as a monolithic entity and for focusing only on individual behavioral determinants of health. When broader determinants are acknowledged, they are often described in solely economic terms (ie, comparing health risks of higher class versus lower class sex workers). Drawing from Pierre Bourdieu, I describe women's sex work in Antananarivo, Madagascar as a social 'field' and demonstrate that this field is both highly complex and highly structured. Fourteen months of ethnographic fieldwork (December 2002-December 2003; May-June 2004) in Antananarivo with women sex workers (n approximately 60) and community members (n approximately 85) informed a description of the community's understanding of the sex work field and its contrast to the lived experience of key informant sex workers. Women who sell sex were categorized by their communities into three social positions--ambony (high), antonony (middle) and ambany (low)--which were differentiated by economic capital (earnings per sexual exchange) and symbolic capital (prestige associated with race, ethnicity and moral demeanor). Women who occupied the antonony social position held the greatest volumes of symbolic capital both because they were identified as belonging to the local dominant ethnic group, and because they demonstrated discretion and shame in their sex work practice. Alternatively, women who occupied the ambony and ambany positions openly practiced their sex work and were associated with ethnic or racial minority identities, contributing to their lower volumes of symbolic capital. Symbolic capital influenced unique health vulnerabilities, such as to sexually transmitted disease, by social position through mechanisms operating from the institutional to the interpersonal level. This analysis illustrates the value of examining sex work as a social field, specifically the importance of capturing more than economic capital in order to understand sex workers' unique health vulnerabilities and concerns. PMID:19362403

Stoebenau, Kirsten

2009-06-01

312

A refined chronology of prehistoric Madagascar and the demise of the megafauna  

NASA Astrophysics Data System (ADS)

The vertebrate community of Madagascar is one of the most unique and diverse on Earth, yet faunal diversity today is just a fraction of that present in the Pleistocene and Early Holocene. An understanding of the chronology of extinction relative to climate change and anthropogenic factors is essential to test hypotheses for extinction. Here, I combine over 200 new radiocarbon dates with published 14C dates from extinct and extant subfossil vertebrates. These new data provide evidence for the prolonged existence of both extant and extinct endemic terrestrial vertebrate species well before human arrival, with habitation of some localities extending back before the Last Glacial Maximum. I analyze the data for patterns among body sizes and ecoregions in relation to four major historical events: human arrival (ca 2500 years ago), establishment of human settlements (ca 1500 years ago), Late Holocene aridification (peaking ca 1000 years ago), and European arrival (ca 500 years ago). Patterns in endemic species abundance after human arrival differ depending on body size and geographic location. Within the first 500 years after human arrival, there were population declines in (1) very large species (>150 kg) and large species (10-150 kg) in the Dry Deciduous Forest, (2) large species in the Central Highlands, and (3) very large species in the Spiny Thicket. This first pulse of declines was likely triggered by human predation. Large species continued to be well represented in the Spiny Thicket and Succulent Woodland until ca 1000 years ago, when their populations plummeted. This second pulse of declines may have been solely triggered by continued human predation, or it may have resulted from a combination of increasing Late Holocene aridity and human impacts in the form of hunting and habitat modification. The abundance of endemic animals weighing <10 kg increased dramatically in the aftermath of the decline in large-bodied species.

Crowley, Brooke E.

2010-09-01

313

Petrology of ultramafic xenoliths in Cenozoic alkaline rocks of northern Madagascar (Nosy Be Archipelago)  

NASA Astrophysics Data System (ADS)

Late Miocene basanites of Nosy Be and Nosy Sakatia islands (Nosy Be Archipelago, northern Madagascar) carry spinel-facies anhydrous ultramafic xenoliths (lherzolites, harzburgites and wehrlites). Geothermobarometric estimates indicate that these xenoliths derive from shallow mantle depths of 35-40 km, with those from Nosy Be island showing equilibration T (averages in the range of 945-985 °C) lower than the Nosy Sakatia analogues (averages ranging from 1010 to 1110 °C). One Nosy Sakatia mantle xenolith exhibits relatively fertile lherzolite composition, with trace and major element mineral chemistry consistent with a residual character after low degrees (1-2%) of mafic melt extraction. We interpret this composition as that resembling a depleted mantle (DM)-like lithospheric composition before metasomatic overprints. The other lherzolites and harzburgites display petrochemical characters consistent with variable extent of partial melting (up to 18%), associated with pronounced metasomatic overprints caused by migrating melts, as highlighted by enrichments in highly incompatible trace elements (e.g. light rare earth elements, LREE and Sr), together with the abundant occurrence of wehrlitic lithologies. The variability of petrochemical features points to different styles of metasomatism and metasomatic agents. The estimated composition of the parental melts of wehrlites matches that of host basanites. The combination of this evidence with the petrographic features, characterized by coarse-granular to porphyroclastic textures and by the presence of olivine without kink-banding, suggests that wehrlites are veins or pockets of high pressure cumulates within the mantle peridotite. The same melts also metasomatized via porous-flow percolation some lherzolites and harzburgites. Distinctly, a group of lherzolites and harzburgites was metasomatized by a different alkaline melt having markedly lower incompatible trace element contents. Late infiltration of metasomatic fluids is responsible for the spongy texture of some clinopyroxenes of lherzolites, harzburgites and wehrlites.

Rocco, Ivana; Lustrino, Michele; Zanetti, Alberto; Morra, Vincenzo; Melluso, Leone

2013-01-01

314

Successful contracting of prevention services: fighting malnutrition in Senegal and Madagascar.  

PubMed

There are very few documented large-scale successes in nutrition in Africa, and virtually no consideration of contracting for preventive services. This paper describes two successful large-scale community nutrition projects in Africa as examples of what can be done in prevention using the contracting approach in rural as well as urban areas. The two case-studies are the Secaline project in Madagascar, and the Community Nutrition Project in Senegal. The article explains what is meant by 'success' in the context of these two projects, how these results were achieved, and how certain bottlenecks were avoided. Both projects are very similar in the type of service they provide, and in combining private administration with public finance. The article illustrates that contracting out is a feasible option to be seriously considered for organizing certain prevention programmes on a large scale. There are strong indications from these projects of success in terms of reducing malnutrition, replicability and scale, and community involvement. When choosing that option, a government can tap available private local human resources through contracting out, rather than delivering those services by the public sector. However, as was done in both projects studied, consideration needs to be given to using a contract management unit for execution and monitoring, which costs 13-17% of the total project's budget. Rigorous assessments of the cost-effectiveness of contracted services are not available, but improved health outcomes, targeting of the poor, and basic cost data suggest that the programmes may well be relatively cost-effective. Although the contracting approach is not presented as the panacea to solve the malnutrition problem faced by Africa, it can certainly provide an alternative in many countries to increase coverage and quality of services. PMID:10787654

Marek, T; Diallo, I; Ndiaye, B; Rakotosalama, J

1999-12-01

315

Physical influence on biological production along the western shelf of Madagascar  

NASA Astrophysics Data System (ADS)

In September 2009, the R.V. Dr. Fridtjof Nansen surveyed the western coast of Madagascar. Environmental parameters of temperature, salinity, fluorescence and oxygen were profiled with a CTD probe and continuously underway at 5 m utilising a thermosalinograph equipped with a fluorescence sensor. A ship mounted Acoustic Doppler Current Profiler (ADCP) provided current profiles down to 250 m, while estimates of biomass were obtained from acoustics and trawling was used for species identification. In addition, visual whale observations were conducted. The survey revealed three areas that were identified as upwelling regions, namely the Southern Coast (26°S), offshore from Cap St. André (16°S) and near Nosy Be Island (13°S). In these upwelling regions, acoustic estimates, trawling and whale observations indicated high biological productivity. The total acoustic estimate for the whole western coast was as low as 62 000 t, typical for tropical waters. In addition to the upwelling areas, high biological productivity was also found outside river mouths. Ship born wind measurements, as well as re-analysed wind fields, indicated that the southern coast upwelling cell was wind-driven and had a larger extent than reported earlier. The wind conditions were not favourable for upwelling in the two northernmost upwelling cells. Here the ADCP showed high bottom velocities (>1 m s-1) oriented northeast. These currents were probably forced by the migrating eddies in the area as indicated by the remotely sensed Sea Level Anomaly (SLA). Such currents induce bottom friction layer transport oriented towards the coast, thus driving upwelling, although not necessarily penetrating all the way to the surface layer as was the case near Cap St. André.

Pripp, T.; Gammelsrød, T.; Krakstad, J. O.

2014-02-01

316

"Even with Higher Education You Remain a Woman": A Gender Perspective on Higher Education and Social Change in the Toliara Region of Madagascar  

ERIC Educational Resources Information Center

This article investigates some issues related to gender and education based on a qualitative, empirical study of women in higher education in the Toliara region of Madagascar. The focus is on how women's participation in higher education has created changes in gender relations, and how these women have succeeded in achieving higher education. In…

Skjortnes, Marianne; Zachariassen, Heidi Holt

2010-01-01

317

Look at That!: Using Madagascar Hissing Cockroaches to Develop and Enhance the Scientific Inquiry Skill of Observation in Middle School Students  

ERIC Educational Resources Information Center

Middle school students can develop and enhance their observation skills by participating in teacher-guided scientific inquiry (NRC 1996) activities where they observe animals that tend to act in known, predictable ways. Madagascar hissing cockroaches ("Gromphadorhina portentosa") are one such animal. This article presents beginning, intermediate,…

Wagler, Ron

2011-01-01

318

Population Ecology of the Ring-Tailed Lemur, Lemur catta, and the White Sifaka, Propithecus verreauxi verreauxi, at Berenty, Madagascar, 1981  

Microsoft Academic Search

The diurnal lemurs Propithecus verreauxi verreauxi and Lemur catta at Berenty in southern Madagascar, have been studied for the last 30 years. The August 1981 census indicates that the population size of L. catta remains stable at 150 adults but that P. v. verreauxi troops have become fragmented and scattered and the population is apparently increasing. Eight different vegetation types

C. J. Howarth; J. M. Wilson; A. P. Adamson; M. E. Wilson; M. J. Boase

1986-01-01

319

Exit the State: Decentralization and the Need for Local Social, Political, and Economic Considerations in Water Resource Allocation in Madagascar and Kenya  

Microsoft Academic Search

This paper focuses on the iconoclasticism of water as a plentiful resource and the near universalization of decentralizing institutions to manage it. The authors explore two agro-pastoral regions — Ambovombe District (Madagascar) and Tana River District (Kenya) — and consider institutional change, particularly the disengaging state, the lack of fiscal and administrative support throughout decentralization, community responses, and informal private

Richard Marcus; Joseph Onjala

2008-01-01

320

Habitat structure and proximity to forest edge affect the abundance and distribution of forest-dependent birds in tropical coastal forests of southeastern Madagascar  

Microsoft Academic Search

Despite the fact that Madagascar is classified a biological `hotspot' due to having both high levels of species endemism and high forest loss, there has been no published research on how Madagascan bird species respond to the creation of a forest edge or to degradation of their habitat. In this study, we examined how forest bird communities and different foraging

James E. M. Watson; Robert J. Whittaker; Terence P. Dawson

2004-01-01

321

A TAXONOMIC REVISION OF GOUANIA (RHAMNACEAE) IN MADAGASCAR AND THE OTHER ISLANDS OF THE WESTERN INDIAN OCEAN (THE COMORO AND MASCARENE ISLANDS, AND THE SEYCHELLES)1  

PubMed Central

A taxonomic revision of the genus Gouania Jacq. (Rhamnaceae) is presented for Madagascar and the other western Indian Ocean islands. Seventeen species are recognized, of which nine are described and published as new (all endemic to Madagascar): G. ambrensis Buerki, Phillipson & Callm., G. callmanderi Buerki, G. cupreifolia Buerki, Phillipson & Callm., G. cupuliflora Buerki, Phillipson & Callm., G. gautieri Buerki, Phillipson & Callm., G. perrieri Buerki, Phillipson & Callm., G. phillipsonii Buerki, G. taolagnarensis Buerki, Phillipson & Callm., and G. zebrifolia Buerki, Phillipson & Callm. Sixteen species occur in Madagascar, of which 13 are endemic and three are common to Madagascar and one or more of the smaller Indian Ocean islands. The latter include G. laxiflora Tul., a species which is also present on mainland Africa. One species, G. mauritiana Lam., is endemic to Réunion Island. We recognize two subspecies within G. scandens (Gaertn.) R. B. Drumm.: G. scandens subsp. scandens and G. scandens subsp. glandulosa (Boivin ex Tul.) Buerki, Phillipson & Callm., the latter transferred from G. glandulosa Boivin ex Tul. Past confusion about the identity of this species is discussed. Five names are lectotypified: G. aphrodes Tul., G. glandulosa [= G. scandens subsp. glandulosa], G. laxiflora, G. lineata Tul., and G. tiliifolia Lam. Both lectotype and epitype are designated for G. mauritiana. Conservation assessments are provided for all species within their primary areas of occurrence. PMID:22053117

Buerki, Sven; Phillipson, Peter B.; Callmander, Martin W.

2011-01-01

322

Unravelling the linkages between the millennium development goals for poverty, education, access to water and household water use in developing countries: Evidence from Madagascar  

Microsoft Academic Search

All members of the United Nations have pledged to meet eight Millennium Development Goals (MDGs) by the year 2015. This study looks at the MDG objectives and linkages between poverty, education, access to water, and household water use based on primary data collected in Madagascar. We find strong links between these MDGs. Better educated and higher income households rely significantly

Bruce Larson; Bart Minten; Ramy Razafindralambo

2006-01-01

323

Genome-wide evidence of Austronesian-Bantu admixture and cultural reversion in a hunter-gatherer group of Madagascar  

PubMed Central

Linguistic and cultural evidence suggest that Madagascar was the final point of two major dispersals of Austronesian- and Bantu-speaking populations. Today, the Mikea are described as the last-known Malagasy population reported to be still practicing a hunter-gatherer lifestyle. It is unclear, however, whether the Mikea descend from a remnant population that existed before the arrival of Austronesian and Bantu agriculturalists or whether it is only their lifestyle that separates them from the other contemporary populations of South Madagascar. To address these questions we have performed a genome-wide analysis of >700,000 SNP markers on 21 Mikea, 24 Vezo, and 24 Temoro individuals, together with 50 individuals from Bajo and Lebbo populations from Indonesia. Our analyses of these data in the context of data available from other Southeast Asian and African populations reveal that all three Malagasy populations are derived from the same admixture event involving Austronesian and Bantu sources. In contrast to the fact that most of the vocabulary of the Malagasy speakers is derived from the Barito group of the Austronesian language family, we observe that only one-third of their genetic ancestry is related to the populations of the Java-Kalimantan-Sulawesi area. Because no additional ancestry components distinctive for the Mikea were found, it is likely that they have adopted their hunter-gatherer way of life through cultural reversion, and selection signals suggest a genetic adaptation to their new lifestyle. PMID:24395773

Pierron, Denis; Razafindrazaka, Harilanto; Pagani, Luca; Ricaut, Francois-Xavier; Antao, Tiago; Capredon, Melanie; Sambo, Clement; Radimilahy, Chantal; Rakotoarisoa, Jean-Aime; Blench, Roger M.; Letellier, Thierry; Kivisild, Toomas

2014-01-01

324

How Much Variation Can One Ant Species Hold? Species Delimitation in the Crematogaster kelleri-Group in Madagascar  

PubMed Central

We investigated the species-level taxonomy of the Malagasy Crematogaster (Crematogaster) kelleri-group and an additional more distantly related species of the same subgenus. Morphological data from worker, queen and male ants, as well as genetic data from three nuclear genes (long wavelength rhodopsin, arginine kinase and carbomoylphosphate synthase) and one mitochondrial marker (cytochrome oxidase I) led to the recognition of six species. Within the C. kelleri-group, three new species are described: C. hazolava Blaimer sp. n., C. hafahafa Blaimer sp. n. and C. tavaratra Blaimer sp. n. The previously described taxa C. kelleri Forel and C. madagascariensis André are validated by our analysis. Conversely, our data suggests synonymy of C. adrepens Forel (with C. kelleri) and C. gibba Emery (with C. madagascariensis). A more distantly related and phylogenetically isolated species, C. tsisitsilo Blaimer sp. n., is further described. We report high levels of morphological and molecular variation in C. kelleri and illustrate that this variation can be explained partly by geography. Species descriptions, images, distribution maps and identification keys based on worker ants, as well as on queen and male ants where available, are presented for all six species. Our work highlights the elevated species richness of Crematogaster ants throughout Madagascar’s humid forests, especially in the far northern tip of the island, and the need to use multiple data sources to ensure clear demarcation of this diversity. PMID:23874503

Blaimer, Bonnie B.; Fisher, Brian L.

2013-01-01

325

Laboratory diagnosis of sexually transmitted infections in women with genital discharge in Madagascar: implications for primary care.  

PubMed

Women seeking care in Madagascar for genital discharge (n = 1,066) were evaluated for syphilis seroreactivity; bacterial vaginosis (BV) and trichomoniasis. Chlamydial infection was assessed by ligase chain reaction (LCR) and by direct immunofluorescence (IF); gonorrhoea by direct microscopy, culture and LCR. Leucocytes were determined in endocervical smears and in urine using leucocyte esterase dipstick (LED). Gonococcal isolates were tested for minimal inhibitory concentrations. BV was found in 56%, trichomoniasis in 25%, and syphilis in 6% of the women. LCR detected gonorrhoea in 13% and chlamydial infection in 11% of the women. Detection of Gram(-) intracellular diplococci in endocervical smears, and gonococcal culture were respectively 23% and 57% sensitive and 98% and 100% specific compared to LCR. Chlamydia antigen detection by IF was 75% sensitive and 77% specific compared to LCR. Leucocytes in endocervical smears and LED testing lacked precision to detect gonococcal and chlamydial infections. Of 67 gonococcal strains evaluated, 19% were fully susceptible to penicillin, 33% to tetracycline; all were susceptible to ciprofloxacin, ceftriaxone, and spectinomycin. Patients who present with genital discharge in Madagascar should be treated syndromically for gonococcal and chlamydial infections and screened for syphilis. Gonorrhoea should be treated with ciprofloxacin. PMID:12230924

Behets, F M-T F; Andriamiadana, J; Randrianasolo, D; Rasamilalao, D; Ratsimbazafy, N; Dallabetta, G; Cohen, M S

2002-09-01

326

[Management of sexually transmitted diseases by the syndrome approach and voluntary HIV screening in a specialized dispensary in Antananarivo (Madagascar)].  

PubMed

In 1994, Médecins du Monde opened a free health centre specialized in STD/AIDS in an ill-favored district of Antananarivo, the Malagasy capital of Madagascar. Besides the medical treatment of Sexually Transmitted Diseases (STD) and AIDS, the centre is responsible for the Information, Education and Communication activities (IEC) within and without the centre towards the residents of the 67 hectares district and the high-risk populations (prostitutes, truck-drivers and transvestites). The project aimed at both preventing the spreading of the VIH infection and reducing the incidence of STD. As the Ministry of Health directed, a syndromic method was applied since 1997 regarding STD. Results for 1998 showed the predominance of the association Neisseria gonorrhae-Chlamydiae among the consultants of both sexes. Negative results from 1,218 HIV serological tests carried out seemed confirm the low prevalence of the HIV infection in Madagascar. Yet, the percentage of positive syphilis serology among the tested consultants was lower than that mentioned in previous surveys. Finally, it appears that the syndromic method is of high interest for the countries with limited laboratory capacities. PMID:12463035

Gleize, L; Randriamanga, R; Ratsimbazafy, N; Rakotonandrasana, S; Durand, P; Le Bot, F

2000-01-01

327

Ethnobotanical and economic value of Ravenala madagascariensis Sonn. in Eastern Madagascar  

PubMed Central

Background Known worldwide as the “traveler’s tree”, the Malagasy endemic species Ravenala madagascariensis Sonn. (Strelitziaceae) is considered as an iconic symbol of Madagascar. It is a widespread species in the eastern part of the country with four different varieties which are well represented in Ambalabe community. All of them are used for different purposes and the species represents an important cultural value in the lives of the local population. However, uses of Ravenala are only generally well known by local population. Thus, in this study, we report on the different uses of Ravenala and its importance to the Ambalabe local people. Methods Semi-structured interviews among 116 people, 59 men and 57 women with ages ranging from 17 to 84 years old, free listing and market surveys were conducted in order to collect the vernacular names, the uses of Ravenala madagascariensis and the price of plant parts sold in local market. Then, the uses were categorized according to Cámara-Leret et al. classification. Results Different parts of the plant are currently used by local population, which are grouped as heart, trunk, leaves, petioles and rachis. Seven categories of use were recorded, most cited include: human food, utensils and tools, and house building. The most commonly used parts are trunk, heart, leaves and petioles for which the price varies between $3-15. Uses mentioned for construction (floor, roofs and wall), human food and utensils and tools are the most frequent and salient for local population. But the use of the plant as first materials for house building is revealed to be the most important for them. Conclusions Ravenala madagascariensis is very important to the Ambalabe communities because for local population, it represents the Betsimisaraka cultural and traditional use of the plant for house building. Moreover, none of its parts are discarded. The harvest and sale of R. madagascariensis for building materials can also provide an additional source of income to the family. Besides, using Ravenala in house construction reduces the use of slow growing trees and contributes to the sustainable use of natural forest resources. PMID:25027625

2014-01-01

328

FRN TECHNIQUES (137Cs 210Pbex) DOCUMENT SOIL EROSION SOIL REDISTRIBUTION MANUALLY-TILLED HILLSLOPES MADAGASCAR HIGHLAND N. Rabesiranana M. Rasolonirina A. F. Solonjara H. N. Ravoson Raoelina Andriambololona  

EPA Pesticide Factsheets

Search instead for FRN TECHNIQUES (137Cs 210Pbex) DOCUMENT SOIL EROSION SOIL REDISTRIBUTION MANUALLY-TILLED HILLSLOPES MADAGASCAR HIGHLAND N. Rabesiranana M. Rasolonirina A. F. Solonjara H. N. Ravoson Raoelina Andriambololona ?

329

Entomological and parasitological impacts of indoor residual spraying with DDT, alphacypermethrin and deltamethrin in the western foothill area of Madagascar  

PubMed Central

Background In Madagascar, indoor residual spraying (IRS) with insecticide was part of the national malaria control programme since the middle of the twentieth century. It was mainly employed in the highlands and the foothill areas, which are prone to malaria epidemics. Prior to a policy change foreseeing a shift from DDT to pyrethroids, a study was carried out to assess the entomological and parasitological impacts of IRS in areas with DDT or pyrethroids and in areas without IRS. Methods The study was carried out from October 2002 to February 2005 in three communes of the western foothill area of Madagascar. Two communes received IRS with DDT in February 2003, then IRS with pyrethroids (alphacypermethrin or deltamethrin) in February 2004. The third commune remained untreated. Mosquitoes were collected at night using human landing catches and early in the morning in resting places. Blood smears were obtained from schoolchildren and microscopically examined for Plasmodium presence. Results In total, 18,168 human landing mosquitoes and 12,932 resting anophelines were collected. The Anopheles species caught comprised 10 species. The main and most abundant malaria vector was Anopheles funestus (72.3% of human-seeking malaria vectors caught indoors). After IRS had taken place, this species exhibited a lower human biting rate and a lower sporozoite index. Overall, 5,174 blood smears were examined with a mean plasmodic index of 19.9%. A total of four Plasmodium species were detected. Amongst tested school children the highest plasmodial index was 54.6% in the untreated commune, compared to 19.9% in the commune sprayed with DDT and 11.9% in the commune sprayed with pyrethroid. The highest prevalence of clinical malaria attacks in children present at school the day of the survey was 33% in the untreated commune compared to 8% in the areas which received IRS. Conclusion In terms of public health, the present study shows (1) a high efficacy of IRS with insecticide, (2) a similar efficacy of DDT and pyrethroid and (3) a similar efficacy of alphacypermethrin and deltamethrin. The use of IRS with DDT and pyrethroid greatly decreased the vector-human contact, with an associated decrease of the plasmodial index. However malaria transmission did not reach zero, probably due to the exophilic host-seeking and resting behaviours of the malaria vectors, thus avoiding contact with insecticide-treated surfaces indoors. The study highlights the strengths and weaknesses of the IRS implementation and the need for complementary tools for an optimal vector control in Madagascar. PMID:24423246

2014-01-01

330

A fatal neuroinvasive West Nile virus infection in a traveler returning from Madagascar: clinical, epidemiological and veterinary investigations.  

PubMed

Abstract. A 58-year-old woman living in Reunion Island and returning from Madagascar was hospitalized for neuroinvasive encephalitis and died 1 month later. West Nile virus (WNV) infection was biologically confirmed by detection of immunoglobulin M (IgM) reactive with WNV antigens in both cerebrospinal fluid and serum, and weak neutralizing activity was also detected. A veterinary survey performed in her traveling area showed a seroprevalence of WNV of 28.7% (95% confidence interval [CI] = 21.1-36.3) in adult poultry, confirming an active circulation of the virus. Development of a severe form could be related to a weak antibody response, because the patient presented low IgM and IgG titers. This case report underlines the constant risk of emergence of West Nile in Indian Ocean territories, including Reunion Island where competent vectors are widely present during the whole year. PMID:23751400

Larrieu, Sophie; Cardinale, Eric; Ocquidant, Philippe; Roger, Matthieu; Lepec, Richard; Delatte, Hélène; Camuset, Guillaume; Desprès, Philippe; Brottet, Elise; Charlin, Cyril; Michault, Alain

2013-08-01

331

Molecular characterization of rotavirus strains circulating among children with acute gastroenteritis in Madagascar during 2004-2005.  

PubMed

A survey was undertaken of the etiology of acute gastroenteritis in children <16 years of age in Antananarivo, Madagascar, from May 2004 through May 2005. With use of electron microscopy of fecal specimens, 104 (36%) of 285 children were found to be infected with rotavirus. Rotavirus strain characterization was undertaken using enzyme-linked immunosorbent assay, electropherotyping, reverse-transcription polymerase chain reaction genotyping, and nucleotide sequencing. The predominant group A rotavirus strain types identified were P[4]G2 (62%) and P[8]G9 (23%). Nucleotide sequence analysis of the VP7 genes of selected Malagasy G2 and G9 strains demonstrated similarity with those of other recently identified African rotavirus strains belonging to the same genotype. PMID:20684699

Adiku, T K; Dove, W; Grosjean, P; Combe, P; Nakagomi, T; Nakagomi, O; Hart, C A; Cunliffe, N A

2010-09-01

332

A Fatal Neuroinvasive West Nile Virus Infection in a Traveler Returning from Madagascar: Clinical, Epidemiological and Veterinary Investigations  

PubMed Central

A 58-year-old woman living in Reunion Island and returning from Madagascar was hospitalized for neuroinvasive encephalitis and died 1 month later. West Nile virus (WNV) infection was biologically confirmed by detection of immunoglobulin M (IgM) reactive with WNV antigens in both cerebrospinal fluid and serum, and weak neutralizing activity was also detected. A veterinary survey performed in her traveling area showed a seroprevalence of WNV of 28.7% (95% confidence interval [CI] = 21.1–36.3) in adult poultry, confirming an active circulation of the virus. Development of a severe form could be related to a weak antibody response, because the patient presented low IgM and IgG titers. This case report underlines the constant risk of emergence of West Nile in Indian Ocean territories, including Reunion Island where competent vectors are widely present during the whole year. PMID:23751400

Larrieu, Sophie; Cardinale, Eric; Ocquidant, Philippe; Roger, Matthieu; Lepec, Richard; Delatte, Helene; Camuset, Guillaume; Despres, Philippe; Brottet, Elise; Charlin, Cyril; Michault, Alain

2013-01-01

333

Comparative analysis of active constituents in Centella asiatica samples from Madagascar: application for ex situ conservation and clonal propagation.  

PubMed

A comparative quantitative analysis of the active triterpenoids in Centella asiatica samples collected in different locations in Madagascar was carried out to evaluate the natural variability in triterpenoid content and to select elite samples for further ex situ germplasm conservation and clonal propagation. The highest asiaticoside content (6.42%) was measured in samples collected in Mangoro region. In vitro propagation of C. asiatica was successfully achieved in hormone-free medium. Although lower asiaticoside content was detected in 8-week-old vitro plants, the Mangoro sample still showed the highest content in this triterpenoid constituent (1.78%). Acetoxycentellynol, a C(15)-polyacetylene, was found to be accumulated up to 18 times more in in vitro plants as compared to plant material collected in situ. PMID:17560738

Randriamampionona, Denis; Diallo, Billo; Rakotoniriana, Francisco; Rabemanantsoa, Christian; Cheuk, Kiban; Corbisier, Anne-Marie; Mahillon, Jacques; Ratsimamanga, Suzanne; El Jaziri, Mondher

2007-12-01

334

[Resurgence of the plague in the Ikongo district of Madagascar in 1998. 2. Reservoirs and vectors implicated].  

PubMed

Our survey of mammals and fleas arose as a result of an outbreak of bubonic plague at an usually low altitude in the Ikongo district (Madagascar), while a previous study had found anti-F1 antibodies in an endemic hedgehog. Animals were sampled with live traps in two hamlets (Antanambao-Vohidrotra, 540 m alt. and Ambalagoavy, 265 m alt.) and with pitfall traps in a neighbouring forest (750 m alt.). Rat fleas were collected by brushing the fur and free-living fleas by use of light traps. The introduced shrew Suncus murinus was found only in the village of Ambalagoavy while the black rat (Rattus rattus) was found in all three sites and the only seropositive rat was caught at Antanambao-Vohidrotra. In contrast, among the Tenrecidae (endemic shrews and hedgehogs) found in the forest near the first village, four animals were found seropositive for anti-F1 antibodies. One of them was carrying the endemic flea Paractenopsyllus pauliani, not yet reported as a vector of plague. The endemic vector of plague, Synopsyllus fonquerniei, was found only in the first village of Antanambao-Vohidrotra, and the cosmopolite flea Xenopsylla cheopis only in Ambalagoavy. Although no Yersinia pestis could be isolated and no F1-antigen could be detected in these animals, we found evidence of the recent transmission of plague in Antanambao-Vohidrotra and the nearby forest, but not in Ambalagoavy. These data corroborate with the sylvatic plague cycle hypothesis in Madagascar and its involvement in the outcome of the bubonic plague outbreak in this district. PMID:11475029

Duplantier, J M; Duchemin, J B; Ratsitorahina, M; Rahalison, L; Chanteau, S

2001-05-01

335

Stratigraphic Analysis of Upper Cretaceous Rocks in the Mahajanga Basin, Northwestern Madagascar: Implications for Ancient and Modern Faunas.  

PubMed

Upper Cretaceous strata of the Mahajanga Basin, northwestern Madagascar, yield some of the most significant and exquisitely preserved vertebrate fossils known from Gondwana. The sedimentology of these strata and their stratigraphic relations have been the focus of renewed geological investigations during the course of five expeditions since 1993. We here designate stratotypes and formalize the terrestrial Maevarano Formation, with three new members (Masorobe, Anembalemba, Miadana), and the overlying marine Berivotra Formation. The Maevarano Formation accumulated on a broad, semiarid alluvial plain bounded to the southeast by crystalline highlands and to the northwest by the Mozambique Channel. The Berivotra Formation was deposited in an open marine setting that evolved from a clastic- to a carbonate-dominated shelf, resulting in deposition of the overlying Betsiboka limestone of Danian age. New stratigraphic data clearly indicate that the Maevarano Formation correlates, at least in part, with the Maastrichtian Berivotra Formation, and this in turn indicates that the most fossiliferous portions of the Maevarano Formation are Maastrichtian in age, rather than Campanian as previously reported. This revised age for the Maevarano vertebrate assemblage indicates that it is approximately contemporaneous with the vertebrate fauna recovered from the Deccan basalt volcano-sedimentary sequence of India. The comparable age of these two faunas is significant because the faunas appear to be more similar to one another than either is to those from any other major Gondwanan landmass. The revised age of the Maevarano Formation, when considered in the light of our recent fossil discoveries, further indicates that the ancestral stocks of Madagascar's overwhelmingly endemic modern vertebrate fauna arrived on the island in post-Mesozoic times. The basal stocks of the modern vertebrate fauna are conspicuously absent in the Maevarano Formation. Finally, the revised age of the Maevarano Formation serves to expand our global perspective on the K/T event by clarifying the age of a diverse, and arguably the best preserved, sample of Gondwanan vertebrates from the terminal Cretaceous. PMID:10769157

Rogers; Hartman; Krause

2000-05-01

336

Assessment of organochlorine pesticides and metals in ring-tailed lemurs (Lemur catta) at Beza Mahafaly Special Reserve, Madagascar.  

PubMed

Like most of Madagascar's endemic primates, ring-tailed lemurs (Lemur catta) face a number of threats to their survival. Although habitat loss is of greatest concern, other anthropogenic factors including environmental contamination may also affect lemur health and survival. In this study, we examined ring-tailed lemurs from the Beza Mahafaly Special Reserve (BMSR), southern Madagascar for exposure to organochlorine (OC) pesticides and metals and examined differences in contaminant concentrations between sexes and among age groups, troops, and habitats. A total of 14 pesticides and 13 metals was detected in lemur blood (24 individuals) and hair (65 individuals) samples, respectively. p,p'-DDT, heptachlor, aldrin, heptachlor epoxide, endrin aldehyde, and endrin were among the most prevalent pesticides detected. Surprisingly, the persistent metabolite of p,p'-DDT, p,p'-DDE, was not detected. The most commonly detected metals were aluminum, zinc, boron, phosphorus, silicon, and copper, whereas metals considered more hazardous to wildlife (e.g. arsenic, cadmium, lead, selenium, vanadium) were not found above detection limits. Overall, concentrations of OC pesticides and metals were low and similar to those considered to be background concentrations in other studies examining the ecotoxicology of wild mammals. Few inter-sex, -age, -troop, and -habitat differences in contaminant concentrations were observed, suggesting a uniform distribution of contaminants within the reserve. Several statistically significant relationships between lemur body size and contaminant concentrations were observed, but owing to the lack of supportive data regarding contaminant exposure in wild primates, the biological significance of these findings remains uncertain. Results of this study document exposure of ring-tailed lemurs at BMSR to multiple OC pesticides and metals and provide essential baseline data for future health and toxicological evaluations of lemurs and other wild primates, especially those in regions with expanding agricultural and mining operations. PMID:19746443

Rainwater, Thomas R; Sauther, Michelle L; Rainwater, Katherine A E; Mills, Rachel E; Cuozzo, Frank P; Zhang, Baohong; McDaniel, Les N; Abel, Michael T; Marsland, Eric J; Weber, Martha A; Youssouf Jacky, Ibrahim Antho; Platt, Steven G; Cobb, George P; Anderson, Todd A

2009-12-01

337

Rivaling the World's Smallest Reptiles: Discovery of Miniaturized and Microendemic New Species of Leaf Chameleons (Brookesia) from Northern Madagascar  

PubMed Central

Background One clade of Malagasy leaf chameleons, the Brookesia minima group, is known to contain species that rank among the smallest amniotes in the world. We report on a previously unrecognized radiation of these miniaturized lizards comprising four new species described herein. Methodology/Principal Findings The newly discovered species appear to be restricted to single, mostly karstic, localities in extreme northern Madagascar: Brookesia confidens sp. n. from Ankarana, B. desperata sp. n. from Forêt d'Ambre, B. micra sp. n. from the islet Nosy Hara, and B. tristis sp. n. from Montagne des Français. Molecular phylogenetic analyses based on one mitochondrial and two nuclear genes of all nominal species in the B. minima group congruently support that the four new species, together with B. tuberculata from Montagne d'Ambre in northern Madagascar, form a strongly supported clade. This suggests that these species have diversified in geographical proximity in this small area. All species of the B. minima group, including the four newly described ones, are characterized by very deep genetic divergences of 18–32% in the ND2 gene and >6% in the 16S rRNA gene. Despite superficial similarities among all species of this group, their status as separate evolutionary lineages is also supported by moderate to strong differences in external morphology, and by clear differences in hemipenis structure. Conclusion/Significance The newly discovered dwarf chameleon species represent striking cases of miniaturization and microendemism and suggest the possibility of a range size-body size relationship in Malagasy reptiles. The newly described Brookesia micra reaches a maximum snout-vent length in males of 16 mm, and its total length in both sexes is less than 30 mm, ranking it among the smallest amniote vertebrates in the world. With a distribution limited to a very small islet, this species may represent an extreme case of island dwarfism. PMID:22348069

Glaw, Frank; Köhler, Jörn; Townsend, Ted M.; Vences, Miguel

2012-01-01

338

Assessing Water Management of Mining Effluent Using Temporal and Spatial Hydrologic Analyses: The Case of QIT Madagascar Minerals  

NASA Astrophysics Data System (ADS)

Associated with the commencement of any water-intensive mining operation is the formation of a set of policies, standards, and sampling protocols that guide the management of all water resources connected to the mining facility, surrounding environment, and affected communities. This study explores the interface between corporate water management and hydrologic methods by evaluating changes in water quality over the course of the mining cycle at QIT Madagascar Minerals (QMM) in Tolagnaro, Madagascar. Sampling and lab research of processed water were conducted following established QMM procedures and then analyzed in conjunction with the complete QMM water quality database. Water quality was analyzed spatially to exhibit how processed water changes as it moves throughout the mining cycle before release into the environment. Graphical representation of the spatial changes in various parameters exhibit deterioration in water quality relative to the source, improvement in quality before being released as effluent, and natural remediation by wetlands before discharge into the Mandromondromotra River. In addition, water quality parameters were evaluated temporally, using data supplied by QMM's Service de l'Eau et Déchets. Yearly and monthly comparisons of hydrological parameters highlight data gaps, the effects of seasonality, and the evolution of water quality monitoring at QMM. Technical evaluation of processed water as it flows through the mining system provides insight into how water monitoring and management can best be adapted at the corporate level to prevent negative impacts on the environment. Water quality data for various parameters from April 2013 at each of the sampling locations. The graphs highlight spatial changes in parameters as water moves from the sources (WD90, Paddock 3), to sites on the mine (500M, Basmin, SCC2), to release points (WMC703, WMC803), to discharge points into the MMM River.

Hoagland, N. E.

2013-12-01

339

Preliminary study of a radiological survey in an abandoned uranium mining area in Madagascar  

NASA Astrophysics Data System (ADS)

The region of Vinaninkarena located in central Madagascar (47°02'40"E, 19°57'17"S), is known to be a high natural radioactive area. Uranium ore was extracted in this region during the 1950s and the early 1960s. In the mid-1960s, mining activities were stopped and the site abandoned. In the meantime, the region, which used to be without any inhabitants, has recently been occupied by new settlers with presumed increase in exposure of the local population to natural ionizing radiation. In order to assess radiological risk, a survey to assess the soil natural radioactivity background was conducted during the year 2004. This study was implemented in the frame of the FADES Project SP99v1b_21 entitled: Assessment of the environmental pollution by multidisciplinary approach, and the International Atomic Energy Agency Technical Cooperation Project MAG 7002 entitled: Effects of air and water pollution on human health. Global Positioning System (GPS) was used to determine the geographical coordinates of the top soil samples (0-15cm) collected. The sampling was performed using a multi integrated scale approach to estimate the spatial variability of the parameters under investigation (U, Th and K) using geo-statistical approach. A total of 205 soil samples was collected in the study site (16 km2). After humidity correction, the samples were sealed in 100 cm3 cylindrical air-tight plastic containers and stored for more than 6 months to reach a secular equilibrium between parents and short-lived progeny (226Ra and progeny, 238U and 234Th). Measurements were performed using a high-resolution HPGe Gamma-detector with a 30% relative efficiency and an energy resolution of 1.8 keV at 1332.5 keV, allowing the determination of the uranium and thorium series and 40K. In case of secular equilibrium, a non-gamma-emitting radionuclide activity was deduced from its gamma emitting progeny. This was the case for 238U (from 234Th), 226Ra (from 214Pb and 214Bi) and 232Th (from 228Ac, 212Pb or 208Tl). Furthermore, in order to assess the radiological effect, the kerma rate in the air at 1 m above ground level was calculated for each sampled points using standard activity-kerma rate conversion coefficients for uranium, thorium series and potassium. Geostatistical interpolation tools (e.g. Inverse Distance Weighting power 2 and Ordinary Kriging) were used to optimize the data set mapping. The measured Potassium-40 activity was 333 Bq kg-1 ± 95% (Mean ± Coefficient of Variation), the Uranium activity was 195 Bq kg-1 ± 53% and the Thorium activity was 139 Bq kg-1 ± 29%. The world average concentrations are reported by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as 400 Bq kg-1 for 40K, 35 Bq kg-1 for 238U and 30 Bq kg-1 for 232Th. The results show that generally, 40K concentrations in soils of the area are slightly lower than the world average value, whereas uranium and thorium series activities are noticeably higher. On average the kerma rate reaches 143 nGy h-1 with a standard deviation of 41 nGy h-1 and a coefficient of variation of 28%. The information obtained was mapped and the dose exposition was also assessed for the local settlers. Key-words: soil contamination, environmental radioactivity, radioecology, dose exposure.

N, Rabesiranana; M, Rasolonirina; F, Solonjara A.; Andriambololona., Raoelina; L, Mabit

2010-05-01

340

Microstructural evidences of garnet plasticity in the continental crust. New example from south Madagascar  

NASA Astrophysics Data System (ADS)

Garnet mechanical behaviour is of great importance to understand the rheological evolution of rocks within the mantle and the lower crust. Well-constrained natural examples of plastically deformed garnets are scarce; consequently their identification and the physical parameters controlling their occurrence are still debated. In southern Madagascar, a granulitic metamorphic event has developed during a late Panafrican - Cambrian, east-west shortening (570 Ma). This has led to the development of vertical transpressive shear zones. Within these zones, we identified variations in garnet microstructure following the deformation sequence. In order to understand this evolution, we carried out a thorough microstructural description of samples using the following techniques: optical microscopy and SEM imaging, EBSD technique (localized lattice-preferred orientation), TEM for dislocation density, EMP for chemical analyses, as well as crystal size distribution, statistic grain boundary and shapes analyses (Lexa et al., 2005). The hand samples were quartzites or two-feldspars quartzo- feldsphatic rocks bearing 10 modal percent of garnet. As strain increases, various garnet textures were observed: Type 1) millimetre-sized rounded garnets bearing two types of inclusions, i.e. elongated quartz ribbons and well oriented sillimanite parallel to the lineation; Type 2) elliptic very elongated and lobed garnets (1 to 8 aspect ratio); Type 3) smaller elongated pinch and swell garnets (1 to 3 aspect ratio); and finally Type 4) rounded small garnets (300 microns in diameter). Type 1 textures are due to multiple nucleation garnets and coalescence controlled by aluminous aggregates (biotite and sillimanite). As strain increases, these large skeleton garnets start to re-crystallise preferentially at the tip of lenticular quartz inclusions, giving Type 2 very elongated garnets with unique CPO. The latter then continues to re-crystallise by sub-grain rotation as underlined by the CPO in situ measurements of new re-orientated grains (Type 3). In the type 4, few large garnets remain and only smaller-sized rounded garnets are left. In these highly deformed rocks, fine sillimanite needles are locally preserved and tilted with respect to the main foliation. All garnets from Type 2 to 4 textures are chemically homogeneous. Data from garnets, quartz, and feldspars are compared for each microstructural type and progressive deformation. The observed microstructures are in accordance with garnet ductility coeval with the deformation of quartz K-feldspar and plagioclase and showing mixing of all phases (random distribution) as well as constant grain size (average diameter 200 microns). Our analyses show that under the high-temperature and dry conditions (850°C) all phases are mechanically active. This indicates convergence of strength minerals marked by contrasting (laboratory derived) rheologies. Lexa, O., Štípská, P., Schulmann, K., Baratoux, L., Kröner, A., 2005. Contrasting textural record of two distinct metamorphic events of similar P-T conditions and different durations. Journal of Metamorphic Geology 23. 649-666. http://petrol.natur.cuni.cz/~ondro/polylx:home

Malamoud, Karim; Martelat, Jean-Emmanuel; Cordier, Patrick; Schulmann, Karel; Lardeaux, Jean-Marc

2010-05-01

341

Sensing landscape level change in soil fertility following deforestation and conversion in the highlands of Madagascar using Vis-NIR spectroscopy  

Microsoft Academic Search

Research data on soil quality are scarce in Madagascar, despite the island's widely recognized problems of soil and environmental degradation. One of the major constraints to properly assessing current status, trends and processes of soil degradation is the high level of costs involved when using conventional soil analytical methods. Previous studies have demonstrated that visible-near-infrared (Vis-NIR) reflectance spectroscopy may permit

Tor-G. Vågen; Keith D. Shepherd; Markus G. Walsh

2006-01-01

342

A new species of the Boophis rappiodes group (Anura, Mantellidae) from the Sahamalaza Peninsula, northwest Madagascar, with acoustic monitoring of its nocturnal calling activity  

PubMed Central

Abstract A new species of treefrog of the Boophis rappiodes group (Anura, Mantellidae) is described from the Sahamalaza – Iles Radama National Park in northwest Madagascar. This new species is green in colour with bright red speckling across its head and dorsum; similar in morphology to other species of this group including: B. bottae, B. rappiodes, B. erythrodactylus and B. tasymena. The new species can be distinguished by its advertisement call and by a genetic divergence of more than 4.9% in the analysed mitochondrial 16S rRNA gene fragment. Its call consists of two note types: a trill and a click; although similar sounding to B. bottae, the trill note of the new species has a faster pulse rate while the click note is predominantly two-pulsed rather than three. All individuals were detected from the banks of two streams in Ankarafa Forest. The new species represents the only member of the B. rappiodes group endemic to Madagascar’s western coast, with the majority of other members known from the eastern rainforest belt. Despite its conspicuous call, it has not been detected from other surveys of northwest Madagascar and it is likely to be a local endemic to the peninsula. The ranges of two other amphibian species also appear restricted to Sahamalaza, and so the area seems to support a high level of endemicity. Although occurring inside a National Park, this species is highly threatened by the continuing decline in the quality and extent of its habitat. Due to these threats it is proposed that this species should be classified as Critically Endangered according to the IUCN Red List criteria. PMID:25152689

Penny, Samuel G.; Andreone, Franco; Crottini, Angelica; Holderied, Marc W.; Rakotozafy, Lovasoa Sylviane; Schwitzer, Christoph; Rosa, Goncalo M.

2014-01-01

343

Effects of spatial proximity and alliances on dominance relations among female ring-tailed lemurs ( Lemur catta ) at Berenty Reserve, Madagascar  

Microsoft Academic Search

In the present study, we describe a change in the dominance rank of the top-ranking female in a wild troop of ring-tailed\\u000a lemurs (Lemur catta) at Berenty Reserve, Madagascar. After the top-ranking female fell to the bottom-ranking position, she was able to outrank\\u000a a low-ranking female with the support of her adult daughter or an unrelated high-ranking female. These results

Masayuki Nakamichi; Maria L. O. Rakototiana; Naoki Koyama

1997-01-01

344

Natural Disasters and Primate Populations: The Effects of a 2Year Drought on a Naturally Occurring Population of Ring-Tailed Lemurs ( Lemur catta ) in Southwestern Madagascar  

Microsoft Academic Search

We examine demographic patterns from a long-term study (1987–1996) of the population of ring-tailed lemurs in the Beza-Mahafaly Special Reserve, in southwestern Madagascar. In particular, we focus on the effects that a severe drought in 1991 and 1992 had on the population. The population of adult animals peaked in 1991 but decreased rapidly during the subsequent drought and immediate postdrought

Lisa Gould; Robert W. Sussman; Michelle L. Sauther

1999-01-01

345

Genetic tests of the taxonomic status of the ring-tailed lemur (Lemur catta) from the high mountain zone of the Andringitra Massif, Madagascar  

Microsoft Academic Search

A recent survey of the high-mountain zone of the Madagascar Parc National (PN) d'Andringitra revealed the presence of an apparently isolated troop of the ring-tailed lemur Lemur catta. These animals display phenotypic and ecological characteristics that are unusual for the monotypic genus Lemur, thus raising the possibility that they are members of a different undescribed species. We present analyses of

Anne D. Yoder; Jodi A. Irwin; Steven M. Goodman; Soava V. Rakotoarisoa

2000-01-01

346

Vigilance behavior during the birth and lactation season in naturally occurring ring-tailed lemurs ( Lemur catta ) at the Beza-Mahafaly Reserve, Madagascar  

Microsoft Academic Search

I examined the vigilance behavior of adult males and females in two groups of ring-tailed lemurs(Lemur catta)during the birth and lactation season at the Beza-Mahafaly Reserve, southwestern Madagascar. I found no sex difference with\\u000a respect to the rates of overall vigilance, rates of vigilance toward a potential predator or unfamiliar sound, or rates of\\u000a vigilance toward conspecifics from other social

Lisa Gould

1996-01-01

347

Structure and metamorphism of the granitic basement around Antananarivo: A key to the Pan-African history of central Madagascar and its Gondwana connections  

NASA Astrophysics Data System (ADS)

The Precambrian basement of Madagascar acquired a polyphase imprint during the Pan-African orogeny. In northern central Madagascar, emplacement of stratoid alkaline granites at midcrustal depth (4-5 kbars) led to formation of a layered crust in a postcollisional extensional regime at 630 Ma (D1). Subsequently, the structures of the stratoid granites were rotated by the sinistral and transpressive E-W Antananarivo flexure (or virgation) zone (D2). East of Antananarivo the structures of the D1 layered crust and the D2 virgation are crosscut by the steeply dipping N-S foliations of the Angavo belt. Lineations gently plunging to the north attest that the Angavo belt is a major strike-slip shear zone that formed under low-pressure granulitic conditions (3 kbars, 790°C). The nearby porphyritic Carion granite was emplaced at the end of this period of N-S shearing (D3), which can thus be no younger than 530 Ma. Late-Pan-African (580-550 Ma) strike-slip motion along broadly N-S shear zones has been recognized elsewhere in Madagascar and in its Gondwana connections. Continuation of the Angavo belt as one of the high strain belts of the Arabian-Nubian Shield is discussed in the general framework of Gondwana assembly.

NéDéLec, Anne; Ralison, Bruno; Bouchez, Jean-Luc; GréGoire, Vincent

2000-10-01

348

Body mass of wild ring-tailed lemurs in Berenty Reserve, Madagascar, with reference to tick infestation: a preliminary analysis.  

PubMed

In 1999, we measured the body mass of 101 wild ring-tailed lemurs (Lemur catta) inhabiting the Berenty Reserve, Madagascar. In addition, we counted the number of ticks [Haemaphysalis (Rhipistoma) lemuris Hoogstraal, 1953] infesting their facial skin and external auditory meatuses. For both males and females, the body mass appeared to increase until the age of 3 years. With the apparent exception of infants, there were no sexual differences in body mass. Within a group, higher-ranked adult males tended to be heavier than lower-ranked males. In contrast, there was no consistent correlation between the body mass of females and their ranks. Among the study groups, there was a small difference in body mass and significant difference in the number of ticks infesting the facial skin and external auditory meatuses. In particular, lemurs of a group who inhabited an area of gallery forest in the study area exhibited the smallest values of body mass and were severely infested with ticks. Such group variations were not consistently correlated with the reproductive parameters of the study groups. In three groups moderately infested with ticks, ticks infested adult males and subadults more heavily than adult females, juveniles, and infants. PMID:17632687

Koyama, Naoki; Aimi, Mitsuru; Kawamoto, Yoshi; Hirai, Hirohisa; Go, Yasuhiro; Ichino, Shinichiro; Takahata, Yukio

2008-01-01

349

Diversity of lepidopteran stem borers on monocotyledonous plants in eastern Africa and the islands of Madagascar and Zanzibar revisited.  

PubMed

Surveys were completed in Eritrea, Ethiopia, Kenya, Madagascar, Mozambique, Tanzania, Uganda and Zanzibar to assess the lepidopteran stem borer species diversity on wild host plants. A total of 24,674 larvae belonging to 135 species were collected from 75 species of wild host plants belonging to the Poaceae, Cyperaceae and Typhaceae. Amongst them were 44 noctuid species belonging to at least nine genera, 33 crambids, 15 pyralids, 16 Pyraloidea species not yet identified, 25 tortricids and three cossids. The noctuid larvae represented 73.6% of the total number of larvae collected, with 66.3, 3.5 and 3.8% found on Poaceae, Cyperaceae and Typhaceae, respectively. The Crambidae, Pyralidae, Tortricidae and Cossidae represented 19.8, 1.9, 2.5 and 0.1% of the total larvae collected, respectively, with 90.4% of the Crambidae and Pyralidae collected from Poaceae, and 99.7% of the Tortricidae collected from Cyperaceae. The lepidopteran stem borer species diversity in the wild host plants was far more diverse than previously reported. PMID:17201973

Le Ru, B P; Ong'amo, G O; Moyal, P; Ngala, L; Musyoka, B; Abdullah, Z; Cugala, D; Defabachew, B; Haile, T A; Matama, T Kauma; Lada, V Y; Negassi, B; Pallangyo, K; Ravolonandrianina, J; Sidumo, A; Omwega, C O; Schulthess, F; Calatayud, P A; Silvain, J F

2006-12-01

350

AFLP genome scan in the black rat (Rattus rattus) from Madagascar: detecting genetic markers undergoing plague-mediated selection.  

PubMed

The black rat (Rattus rattus) is the main reservoir of plague (Yersinia pestis infection) in Madagascar's rural zones. Black rats are highly resistant to plague within the plague focus (central highland), whereas they are susceptible where the disease is absent (low altitude zone). To better understand plague wildlife circulation and host evolution in response to a highly virulent pathogen, we attempted to determine genetic markers associated with plague resistance in this species. To this purpose, we combined a population genomics approach and an association study, both performed on 249 AFLP markers, in Malagasy R. rattus. Simulated distributions of genetic differentiation were compared to observed data in four independent pairs, each consisting of one population from the plague focus and one from the plague-free zone. We found 22 loci (9% of 249) with higher differentiation in at least two independent population pairs or with combining P-values over the four pairs significant. Among the 22 outlier loci, 16 presented significant association with plague zone (plague focus vs. plague-free zone). Population genetic structure inferred from outlier loci was structured by plague zone, whereas the neutral loci dataset revealed structure by geography (eastern vs. western populations). A phenotype association study revealed that two of the 22 loci were significantly associated with differentiation between dying and surviving rats following experimental plague challenge. The 22 outlier loci identified in this study may undergo plague selective pressure either directly or more probably indirectly due to hitchhiking with selected loci. PMID:20444082

Tollenaere, C; Duplantier, J-M; Rahalison, L; Ranjalahy, M; Brouat, C

2011-03-01

351

A new species of the Boophis rappiodes group (Anura, Mantellidae) from the Sahamalaza Peninsula, northwest Madagascar, with acoustic monitoring of its nocturnal calling activity.  

PubMed

A new species of treefrog of the Boophis rappiodes group (Anura, Mantellidae) is described from the Sahamalaza - Iles Radama National Park in northwest Madagascar. This new species is green in colour with bright red speckling across its head and dorsum; similar in morphology to other species of this group including: B. bottae, B. rappiodes, B. erythrodactylus and B. tasymena. The new species can be distinguished by its advertisement call and by a genetic divergence of more than 4.9% in the analysed mitochondrial 16S rRNA gene fragment. Its call consists of two note types: a trill and a click; although similar sounding to B. bottae, the trill note of the new species has a faster pulse rate while the click note is predominantly two-pulsed rather than three. All individuals were detected from the banks of two streams in Ankarafa Forest. The new species represents the only member of the B. rappiodes group endemic to Madagascar's western coast, with the majority of other members known from the eastern rainforest belt. Despite its conspicuous call, it has not been detected from other surveys of northwest Madagascar and it is likely to be a local endemic to the peninsula. The ranges of two other amphibian species also appear restricted to Sahamalaza, and so the area seems to support a high level of endemicity. Although occurring inside a National Park, this species is highly threatened by the continuing decline in the quality and extent of its habitat. Due to these threats it is proposed that this species should be classified as Critically Endangered according to the IUCN Red List criteria. PMID:25152689

Penny, Samuel G; Andreone, Franco; Crottini, Angelica; Holderied, Marc W; Rakotozafy, Lovasoa Sylviane; Schwitzer, Christoph; Rosa, Gonçalo M

2014-01-01

352

Coprophagy by wild ring-tailed lemurs (Lemur catta) in human-disturbed locations adjacent to the Beza Mahafaly Special Reserve, Madagascar.  

PubMed

Coprophagy occurs in a number of animal species, including nonhuman primates. During the 2003-2004 dry seasons at the Beza Mahafaly Special Reserve, Madagascar, we observed wild ring-tailed lemurs (Lemur catta) consuming dried fecal matter from three different species. Ring-tailed lemurs consumed human feces on 12 occasions, cattle feces twice, and feral dog feces once. Coprophagy in this population may be a behavioral adaptation that provides animals access to energy and nutrients and may be an important nutritional source for older, and/or dentally impaired individuals during the dry season. PMID:17253614

Fish, Krista D; Sauther, Michelle L; Loudon, James E; Cuozzo, Frank P

2007-06-01

353

Signalling molecules and the synthesis of alkaloids in Catharanthus roseus seedlings  

Microsoft Academic Search

The Madagascar periwinkle, Catharanthus roseus, produces numerous alkaloids, several of which have important pharmaceutical uses. Catharanthus seedlings rapidly accumulate the monomeric alkaloids, vindoline, catharanthine and tabersonine, during germination. Various plant signalling molecules were tested for their ability to enhance alkaloid synthesis in Catharanthus seedlings. The compounds tested included plant hormones, fatty acid-derived messengers and agents that can induce systemic-acquired resistance

Rob J. Aerts; Andrea Schäfer; Manfred Hesse; Thomas W. Baumann; Alan Slusarenko

1996-01-01

354

Techniques for the maintenance and propagation of phytoplasmas in glasshouse collections of Catharanthus roseus.  

PubMed

Phytoplasma collections are a vital resource for researchers and diagnosticians studying phytoplasma diseases. They provide material as a point of reference and a research tool to increase our understanding of phytoplasmas and the diseases they cause. This chapter describes the techniques required to create and maintain collections of phytoplasma-infected Catharanthus roseus (Madagascar periwinkle). PMID:22987402

Hodgetts, Jennifer; Crossley, David; Dickinson, Matt

2013-01-01

355

Bone Histology and Primary Growth Rates in Hatchling Titanosaurs from Madagascar: New Insights from Micro-Computed Tomography  

NASA Astrophysics Data System (ADS)

Sauropods are the largest known terrestrial vertebrates and exhibit a greater ontogenetic variation in body size than any other taxon. More than 120 species of sauropods are known from the Jurassic and Cretaceous, and a wealth of specimens documents their enormous adult body sizes. Juvenile sauropods, in contrast, are rare. Though titanosaur eggs containing embryos have been recovered, to date the smallest known post-hatching juveniles are only a little less than half of known adult size, and details of the earliest stages of sauropod ontogeny remain particularly poorly understood. Here we report on two partial skeletons of hatchling Rapetosaurus krausei, a titanosaur from the Upper Cretaceous Maevarano Formation of Madagascar, and provide important new data on primary early stage growth rates in sauropods. The two partial skeletons come from different localities in the Anembalemba Member of the Maevarano Formation. There is no duplication of elements for either specimen. Comparison of greatest length ratios for appendicular elements to those of a complete sub-adult Rapetosaurus confirms that there are only two individuals present, that there is no significant allometry in Rapetosaurus postcranial ontogeny, and that each individual is less than 15% adult size. The smaller specimen includes a sacral neural arch, three caudal centra, three caudal neural arches, left pubis, right femur (maximum length [ml] = 19.3 cm), tibia (ml = 12.7 cm), and metacarpal III, left and right fibulae, humeri, and metatarsal I, and a phalanx. The larger specimen includes a caudal centrum and neural arch, right metacarpal I, right tibia (ml = 17.9 cm), and left metacarpal IV. In order to non-destructively sample these exceptional Rapetosaurus juvenile elements, we employed micro-computed tomography to garner bone histology data. The micro-computed tomography was carried out using an X5000 high-resolution microfocus X-ray CT system located in the Department of Earth Sciences, University of Minnesota. The microfocus head has a minimum focal spot size of < 6 microns and the detector has a pixel pitch of 74.8 ?m. Machine parameters (e.g. voltage, current, tube to detector distance) vary based on sample size and desired magnification. For this study 70-100 kV (260-370 ?A) was sufficient to penetrate the samples and obtain good contrast. We were able to achieve an effective pixel pitch of 36-48 ?m for the larger samples and 14-28 ?m for sub-volumes. 2-D radiographs were collected and these data were reconstructed to produce a 3-D volume for visual analysis, and slices of the 3-D volume for quantitative analysis. Our results indicate that primary bone growth in Rapetosaurus is highly vascularized woven and fibrolamellar bone. However, even in these very small juvenile individuals, endosteal remodeling is common at the mid-diaphysis and extends in some areas into the mid-cortex. The presence of a single line of arrested growth is recorded in each individual. These results are surprising given the small size of the elements, and support the hypothesis that intensive remodeling observed in the bones of older juvenile Rapetosaurus may be dictated, at least in part, by resource limitations during periods of drought/ecological stress recorded in the Maevarano Formation of Madagascar.

Bagley, B. C.; Whitney, M.; Rogers, K. C.

2012-12-01

356

Rectal Carriage of Extended-Spectrum Beta-Lactamase-Producing Gram-Negative Bacilli in Community Settings in Madagascar  

PubMed Central

Background Extended-spectrum ß-lactamase-producing Enterobacteria (ESBL-PE) emerged at the end of the 1980s, causing nosocomial outbreaks and/or hyperendemic situations in hospitals and long-term care facilities. In recent years, community-acquired infections due to ESBL-PE have spread worldwide, especially across developing countries including Madagascar. Objectives This study aimed to determine the prevalence and risk factors of intestinal carriage of ESBL-PE in the community of Antananarivo. Methods Non-hospitalized patients were recruited in three health centers in different socio economic settings. Fresh stool collected were immediately plated on Drigalski agar containing 3 mg/liter of ceftriaxone. Gram-negative bacilli species were identified and ESBL production was tested by a double disk diffusion (cefotaxime and ceftazidime +/? clavulanate) assay. Characterization of ESBLs were perfomed by PCR and direct sequencing . Molecular epidemiology was analysed by Rep-PCR and ERIC-PCR. Results 484 patients were screened (sex ratio ?=?1.03, median age 28 years). 53 ESBL-PE were isolated from 49 patients (carrier rate 10.1%). The isolates included Escherichia coli (31), Klebsiella pneumoniae (14), Enterobacter cloacae (3), Citrobacter freundii (3), Kluyvera spp. (1) and Pantoae sp.(1). In multivariate analysis, only the socioeconomic status of the head of household was independently associated with ESBL-PE carriage, poverty being the predominant risk factor. Conclusions The prevalence of carriage of ESBL in the community of Antananarivo is one of the highest reported worldwide. This alarming spread of resistance genes should be stopped urgently by improving hygiene and streamlining the distribution and consumption of antibiotics. PMID:21829498

Ratovoson, Rila; Ratsima Hariniana, Elisoa; Buisson, Yves; Genel, Nathalie; Decre, Dominique; Arlet, Guillaume; Talarmin, Antoine; Richard, Vincent

2011-01-01

357

On the active principles of the Euphorbiaceae, XII. Highly unsaturated irritant diterpene esters from Euphorbia tirucalli originating from Madagascar.  

PubMed

The latex of Euphorbia tirucalli originating from Madagascar contains as irritant constituents ingenane- and tigliane-type diterpene esters derived from the parent alcohols ingenol and phorbol. The main irritant constituents are isomeric 12,13-acetates, acylates of phorbol as well as 3-acylates of ingenol. As acyl groups, they carry homologous, highly unsaturated aliphatic acids of the general structure CH3-(CH2)m-(CH = CH)n-COOH (m = 2,4; n = 2,3,4,5; total number N of C-atoms = 2n + m + 2). The lack of 4-deoxyphorbol esters in this latex as compared to latex of South African origin is probably indicative of the existence of chemical races of E. tirucalli. In the acyl moiety of phorbol esters investigated in detail, an increasing number of C-atoms or an increasing number of double bonds at a fixed number of C-atoms leads to an increase of irritant activity. As compared to their saturated analogs, corresponding unsaturated phorbol esters exhibit similar irritant activities. On the other hand, by an increasing number of conjugated double bonds in the acyl moieties of phorbol esters, the promoting activity is decreased, thus indicating that irritant activity is a necessary, but insufficient, requirement for promoting activity of phorbol esters. An assessment of a potential carcinogenic risk involved in mass production and handling of the plant should point to the very weak tumor-promoting activity and the chemical instability demonstrated for the diterpene constituents in the latex and hence in all plant parts. PMID:3760879

Fürstenberger, G; Hecker, E

1986-01-01

358

Protected Area Safeguard Tree and Shrub Communities from Degradation and Invasion: A Case Study in Eastern Madagascar  

NASA Astrophysics Data System (ADS)

Despite their prevalence in both developed and developing countries, there have been surprisingly few field assessments of the ecological effectiveness of protected areas. This study aimed to assess the effectiveness of a key protected area in eastern Madagascar, Ranomafana National Park (RNP). We established paired 100 × 4-m vegetation transects (400 m2) within RNP and in remnant forests in the park’s peripheral zone. In each 400-m2 plot, all woody stems >1.5 cm in diameter at breast height were measured and identified to species. All species were also identified as native or non-native. We identified utilitarian species within all transects and they were sorted into use category. We calculated plot-level taxonomic biodiversity and functional diversity of utilitarian species; the latter was calculated by clustering the multivariate distances between species based on their utilitarian traits, and all metrics were tested using paired t-tests. Our results showed that there was significantly higher biodiversity inside RNP than in remnant forests and this pattern was consistent across all diversity metrics examined. Forests not located within the park’s boundary had significantly higher non-native species than within RNP. There was no statistically significant difference in functional diversity of utilitarian species inside RNP vs. remnant forests; however, the overall trend was toward higher diversity inside park boundaries. These findings suggested that RNP has been effective at maintaining taxonomic diversity relative to surrounding unprotected areas and restricting the spread of non-native plants. The results also suggested that low functional redundancy of forests outside of RNP might be of concern, because residents in surrounding villages may have few other substitutes for the services provided by species that are of critical importance to their livelihoods. This study highlights the challenges of trying to reconcile biodiversity conservation with human use of natural resources in economically poor, remote areas.

Brown, Kerry A.; Carter Ingram, J.; Flynn, Dan F. B.; Razafindrazaka, Rova; Jeannoda, Vololoniaina

2009-07-01

359

Beyond an AFLP genome scan towards the identification of immune genes involved in plague resistance in Rattus rattus from Madagascar.  

PubMed

Genome scans using amplified fragment length polymorphism (AFLP) markers became popular in nonmodel species within the last 10 years, but few studies have tried to characterize the anonymous outliers identified. This study follows on from an AFLP genome scan in the black rat (Rattus rattus), the reservoir of plague (Yersinia pestis infection) in Madagascar. We successfully sequenced 17 of the 22 markers previously shown to be potentially affected by plague-mediated selection and associated with a plague resistance phenotype. Searching these sequences in the genome of the closely related species Rattus norvegicus assigned them to 14 genomic regions, revealing a random distribution of outliers in the genome (no clustering). We compared these results with those of an in silico AFLP study of the R. norvegicus genome, which showed that outlier sequences could not have been inferred by this method in R. rattus (only four of the 15 sequences were predicted). However, in silico analysis allowed the prediction of AFLP markers distribution and the estimation of homoplasy rates, confirming its potential utility for designing AFLP studies in nonmodel species. The 14 genomic regions surrounding AFLP outliers (less than 300 kb from the marker) contained 75 genes encoding proteins of known function, including nine involved in immune function and pathogen defence. We identified the two interleukin 1 genes (Il1a and Il1b) that share homology with an antigen of Y. pestis, as the best candidates for genes subject to plague-mediated natural selection. At least six other genes known to be involved in proinflammatory pathways may also be affected by plague-mediated selection. PMID:23237097

Tollenaere, C; Jacquet, S; Ivanova, S; Loiseau, A; Duplantier, J-M; Streiff, R; Brouat, C

2013-01-01

360

Feeding outside the Forest: The Importance of Crop Raiding and an Invasive Weed in the Diet of Gallery Forest Ring-Tailed Lemurs (Lemur catta) following a Cyclone at the Beza Mahafaly Special Reserve, Madagascar  

Microsoft Academic Search

In January 2005, a cyclone hit southern Madagascar, including the Beza Mahafaly Special Reserve, disrupting the flowering\\/fruiting cycle of Tamarindus indica, leaving Lemur catta without its major food resource during reproductive periods. We studied two adjacent groups of L. catta during the late gestation period, and both groups ventured outside the reserve to feed. The Red group (RG) fed daily

M. LaFleur; L. Gould

2009-01-01

361

One reserve, three primates: applying a holistic approach to understand the interconnections among ring-tailed lemurs (Lemur catta), Verreaux's sifaka (Propithecus verreauxi), and humans (Homo sapiens) at Beza Mahafaly Special Reserve, Madagascar  

Microsoft Academic Search

We applied cultural anthropological, ethological, and parasitological methodologies to investigate the interplay among three primate species, ring-tailed lemurs (Lemur catta), Verreaux's sifaka (Propithecus verreauxi), and humans (Homo sapiens) who live within the same habitat (i.e. in sympatry) around the Beza Mahafaly Special Reserve, Madagascar. Through a fusion of these methodologies we hope to provide a holistic understanding of the advantages

James E. Loudon; Michelle L. Sauther; Krista D. Fish; Mandala Hunter-Ishikawa; Youssouf Jacky Ibrahim

362

ASSESSMENT OF HEALTH AND GROWTH OF RING-NECKED PHEASANTS FOLLOWING CONSUMPTION OF INFECTED INSECTS OR CONIDIA OF ENTOMOPATHOGENIC FUNGI, Metarhizium anisopliae var. acridum AND Beauveria bassiana , FROM MADAGASCAR AND NORTH AMERICA  

Microsoft Academic Search

Isolates of two fungi ( Beauveria bassiana and Metarhizium anisopliae var. acridum ) from Madagascar are being developed for control of grasshoppers and locusts, as part of a search for alternatives to environmentally detrimental chemical insecticides. The probable effects of these entomopathogens on nontarget species must be determined before operational use. Birds may become exposed to these fungi either directly,

Dan L. Johnson; Judit E. Smits; Stefan T. Jaronski; David K. Weaver

2002-01-01

363

Post-cropping change and dynamics in soil and vegetation properties after forest clearing: Example of the semi-arid Mikea Region (southwestern Madagascar)  

NASA Astrophysics Data System (ADS)

This study concerns post-cultural dynamics in the semi-arid South-West of Madagascar (Analabo area, near the Mikea Forest). A synchronic comparison was performed on a set of abandoned fields plots aged from 2 to 30 years and on forest and savanna reference ecosystems, located on cambic arenosols developed from same Quaternary dune sands. The studied parameters concerned mainly a few physical and chemical soil properties (density, permeability, compaction, texture, C, N, K, P content). Important changes occur in the post-cultural succession: an increase of the soil density and compaction, and decrease of the soil upper layer permeability. Consequently, slash and burn cultivation leads to a packing and an induration of the soil surface. Results about edaphic indicators have shown that the physical parameters used better discriminate various stages of evolution than the chemical parameters do. The multivariate analysis of soil indicators shows that vegetative succession over 30 years in a forest ecosystem cleared, burnt, cultivated and left, does not lead to features corresponding to a closed-canopy forest but rather to those of a tree savanna with open, mixed woody-herbaceous vegetation. The primary dense dry deciduous regeneration of the primary forest is very low or nil. In the semi-arid SW Madagascar (Analabo region), post-cultural dynamics conditions consists in a savanna-formation process, controlled by: (1) the intensity and duration of the disturbance (during the cultivation phase); and (2) the more drastic environmental conditions (including both climate and soil).

Leprun, Jean-Claude; Grouzis, Michel; Randriambanona, Herizo

2009-07-01

364

Understanding the molecular signatures in leaves and flowers by desorption electrospray ionization mass spectrometry (DESI MS) imaging.  

PubMed

The difference in size, shape, and chemical cues of leaves and flowers display the underlying genetic makeup and their interactions with the environment. The need to understand the molecular signatures of these fragile plant surfaces is illustrated with a model plant, Madagascar periwinkle (Catharanthus roseus (L.) G. Don). Flat, thin layer chromatographic imprints of leaves/petals were imaged using desorption electrospray ionization mass spectrometry (DESI MS), and the results were compared with electrospray ionization mass spectrometry (ESI MS) of their extracts. Tandem mass spectrometry with DESI and ESI, in conjunction with database records, confirmed the molecular species. This protocol has been extended to other plants. Implications of this study in identifying varietal differences, toxic metabolite production, changes in metabolites during growth, pest/pathogen attack, and natural stresses are shown with illustrations. The possibility to image subtle features like eye color of petals, leaf vacuole, leaf margin, and veins is demonstrated. PMID:23848451

Hemalatha, R G; Pradeep, T

2013-08-01

365

Indigenizing Civic Education in Africa: Experience in Madagascar and the Sahel  

ERIC Educational Resources Information Center

In Africa, as in many countries of the South, democratization is sometimes perceived as a process modeled upon outside--and specifically Northern--experience. Formal civic education programs in those countries arguably reflect the same bias and have not always been notably successful. Yet there are rich patterns of civic involvement and democratic…

Antal, Carrie; Easton, Peter

2009-01-01

366

Unusual evolution of silica-under- and -oversaturated alkaline rocks in the Cenozoic Ambohimirahavavy Complex (Madagascar): Mineralogical and geochemical evidence  

NASA Astrophysics Data System (ADS)

The almost unknown Ambohimirahavavy ring complex in the Cenozoic alkaline province of northwestern Madagascar has recently attracted considerable interest because of the discovery of important rare-metal mineralization. The complex consists of arc-shaped bodies made up of silica-under- and -oversaturated syenites and extremely evolved peralkaline granitic dykes, as well as several mafic to felsic volcanic units, including basalt, phonolite and trachyte, all of which have an alkaline affinity. Uranium-lead zircon ages of 24.2 ± 0.6 Ma and 23.5 ± 6.8 Ma have been obtained for nepheline syenites and peralkaline granitic dykes, respectively, which, together with field data and ages of neighboring complexes, support emplacement controlled by regional lithospheric structures, rather than an evolving hot spot. Whole-rock major and trace-element and Sr-Nd isotopic data for the mafic suite suggest that the parental melt of this complex was generated by low degrees of melting of a metasomatized mantle source with residual amphibole. Fractional crystallization of this alkali basaltic melt likely produced the silica-undersaturated suite. We propose that the silica-oversaturated suite evolved from the undersaturated melt after contamination of the latter by crustal material. Further evolution to peralkaline compositions in both suites is attributed mainly to plagioclase and alkali feldspar segregation. Nepheline and feldspar compositions, as well as considerations of mineral equilibria among mafic silicates and Fe-Ti oxide minerals indicate crystallization temperatures of 1000 to 700 °C and an oxygen fugacity of 0.4 to 0.8 log units below the fayalite-magnetite-quartz (FMQ) buffer at 1 kbar for the silica-undersaturated melt, and temperatures of 860 to 570 °C and an oxygen fugacity of 1.5 to 3.8 log units below FMQ for the oversaturated syenitic melt. The undersaturated melt evolved towards a more peralkaline composition. Crystallization of arfvedsonite plus aegirine further reduced the melt the evolution of which ended with fluid exsolution. At late stages of crystallization, the oversaturated melt departed from the reducing trend of the undersaturated melt, evolving towards high oxygen fugacity. Very late exsolution of the fluid permitted concentration of the HFSE in the last stages of magmatic evolution with local production of low-temperature pegmatitic phases extremely enriched in these elements.

Estrade, Guillaume; Béziat, Didier; Salvi, Stefano; Tiepolo, Massimo; Paquette, Jean-Louis; Rakotovao, Soatsitohaina

2014-10-01

367

A new geological framework for south-central Madagascar, and its relevance to the "out-of-Africa" hypothesis  

USGS Publications Warehouse

The Precambrian shield of south-central Madagascar, excluding the Vohibory region, consists of three geologic domains, from north to south: Antananarivo, Ikalamavony-Itremo, and Anosyen-Androyen. The northern Antananarivo domain represents the Neoarchean sector of the Greater Dharwar Craton amalgamated at 2.52-2.48. Ga. The Greater Dharwar Craton is overlain by several groups of Meso- to Neoproterozoic supracrustal rocks (Ambatolampy, Manampotsy, Ampasary, Sahantaha, and Maha Groups) each with a common and diagnostic signature of Paleoproterozoic detrital zircons (2.2-1.8. Ga). The central domain (Ikalamavony-Itremo) consists of two distinct parts. The Itremo Sub-domain, in the east, is a structurally intercalated sequence of Neoarchean gneiss and shallow marine metasedimentary rocks of Paleo-Mesoproterozoic age (Itremo Group), the latter with Paleoproterozoic detrital zircons ranging in age between 2.2 and 1.8. Ga. The Ikalamavony Sub-domain, to the west, contains abundant volcano-clastic metasediments and lesser quartzite (Ikalamavony Group), formed between 1.03. Ga and 0.98. Ga, and intruded by igneous rocks (Dabolava Suite) of Stenian-Tonian age. Structurally intercalated with these are sheets of Neoarchean gneiss (~2.5. Ga) and Neoproterozoic metaclastic rocks (Molo Group). Like the Itremo Group, quartzite of the Ikalamavony Group has detrital zircons of Paleoproterozoic age (2.1-1.8. Ga). The southern domain of Anosyen-Androyen consists of a newly recognized suite of Paleoproterozoic igneous rocks (2.0-1.8. Ga), and stratified supracrustal rocks also having Paleoproterozoic detrital zircons (2.3-1.8. Ga). The contact between the Anosyen-Androyen and Ikalamavony-Itremo domains, formerly known as the Ranotsara-Bongolava shear zone, is a tightly folded and highly flattened boundary that was ductilely deformed in Ediacaran time. It is roughly equivalent to the Palghat-Cauvery shear zone in south India, and it defines approximately the boundary between the Archean Greater Dharwar Craton (to the north) and the Paleoproterozoic terrane of Anosyen-Androyen (to the south).

Tucker, R.D.; Roig, J.Y.; Macey, P.H.; Delor, C.; Amelin, Y.; Armstrong, R.A.; Rabarimanana, M.H.; Ralison, A.V.

2011-01-01

368

This composite image reveals the typical habitat for the periwinkle snail which colonises the tidal splash zone of the upper rock wall, where the grey rock surface is blackened by biofilm  

E-print Network

the opportunity, to survive, grow and reproduce. It is a central tenet of ecology that the abundances of organisms to enrich the habitat overall. We have modelled the concept to explore its potential for applications across many scales of community structure. The next step is to test the model on natural systems." The project

Anderson, Jim

369

Attacks on a wild infant ring-tailed lemur (Lemur catta) by immigrant males at Berenty, Madagascar: interpreting infanticide by males.  

PubMed

An orphaned infant ring-tailed lemur (Lemur catta) was attacked persistently by immigrant males and disappeared with severe wounds at Berenty Reserve, Madagascar. Prior to the attacks, two troop members disappeared. On 20 November 1998, the only resident male in Troop C2B disappeared suddenly. After the disappearance, nine males from three neighboring troops approached, but only six males continued to shadow the troop. Of the females, the one lactating female attacked the males the most frequently. On 21 January 1999, the lactating female disappeared and her infant was orphaned. Subsequently, five attacks on the infant by immigrant males were observed for five consecutive days from January 23 to 27. The aggression was persistent and specifically targeted the infant, suggesting that the attacks were purposeful aggression, rather than redirected or accidental aggression. The primary attacker was the most dominant of the immigrant males, and mated with females in the next mating season. PMID:16229008

Ichino, Shinichiro

2005-10-01

370

Methodological problems and amendments to demonstrate effects of temperature on the epidemiology of malaria. A new perspective on the highland epidemics in Madagascar, 1972-89.  

PubMed

There is a growing consensus that changes in climate will have major consequences for human health through a reduction in the availability of food and an increasing frequency of natural disasters. However, the contribution of higher temperatures to vector-borne diseases, particularly malaria, remains controversial despite the known biological dependence of both vector and pathogen on climate. Misconceptions and inappropriate use of variables and methods have contributed to the controversy. At present there appears to be more support for non-climatic explanations to account for the resurgence of malaria in the African highlands, e.g. the deterioration of malaria control and the development of drug resistance. An attempt is made here to show that dismissing temperature as a driving force in the case of malaria is premature. Using a de-trended time-series of malaria incidence in Madagascar between 1972 and 1989 indicated that a minimum temperature during 2 months at the start of the transmission season can account for most of the variability between years (r2 = 0.66). These months correspond with the months when the human-vector (Anopheles gambiae sensu lato) contact is greatest. The relationship between El Niño Southern Oscillation (ENSO) and temperature (r = 0.79), and ENSO and malaria (r = 0.64), suggests that there might be an increased epidemic risk during post-Niño years in the Madagascar highlands and therefore warrants increased vigilance and extended control efforts in the first half of 2003. This review suggests that the rejection of climate-disease associations in studies so far published may not have used biologically relevant climate parameters. It highlights the importance of identifying more relevant parameters during critical periods of the transmission season in order to aid epidemic forecasting and to assess the potential impact of global warming. PMID:14584363

Bouma, Menno Jan

2003-01-01

371

Biomedical evaluation of free-ranging ring-tailed lemurs (Lemur catta) in three habitats at the Beza Mahafaly Special Reserve, Madagascar.  

PubMed

Complete physical examinations and biomedical sample collection were performed on 70 free-ranging ring-tailed lemurs (Lemur catta) from three different habitats in the Beza Mahfaly Special Reserve (BMSR), in southern Madagascar, to assess the impact of humans and habitat on lemur health. Lemurs were chemically immobilized with ketamine and diazepam administered via blow darts for concurrent biomedical, morphometric, and behavioral studies. Subsets of the animals had blood analyzed for hematology, serum chemistry, micronutrients, fat-soluble vitamins (vitamins A, D, and E), measures of iron metabolism, and polymerase chain reaction assays (PCR) for Toxoplasma gondii, Hemoplasma spp., Bartonella spp., Ehrlichia spp., Anaplasma phagocytophilum, and Neorickettsia risticii. Results were compared on the basis of gender and the habitats at the study site: reserve (intact gallery forest), degraded (human inhabited and altered), and marginal (dry didieracea forest with heavy grazing and tree cutting). Levels of vitamin D, triglycerides, and cholesterol, and measures of iron metabolism for BMSR lemurs were greater than those previously reported for a free-ranging lemur population (Tsimanampetsotsa Strict Nature Reserve, Madagascar) with less access to foods of anthropogenic origin. BMSR ring-tailed lemurs from a habitat with less water (marginal) had higher sodium (P = 0.051), chloride (P = 0.045), osmolality (P = 0.010), and amylase (P = 0.05) levels than lemurs from other BMSR habitats, suggesting that these lemurs were less hydrated. Vitamin D levels of male lemurs were higher (P = 0.011) than those of females at BMSR, possibly because of differences in sunning behavior or differential selection of food items. The biological significance is uncertain for other parameters with statistically significant differences. All samples tested (n = 20) were negative for the pathogens tested using PCR assays. Continued concurrent biomedical and ecological research is needed at BMSR to confirm these results and determine their association with population mortality and fecundity rates. PMID:17679503

Miller, David S; Sauther, Michelle L; Hunter-Ishikawa, Mandala; Fish, Krista; Culbertson, Heather; Cuozzo, P Frank; Campbell, Terry W; Andrews, Gordon A; Chavey, Patricia Sue; Nachreiner, Raymond; Rumbeiha, Wilson; Stacewicz-Sapuntzakis, Maria; Lappin, Michael R

2007-06-01

372

Persistence of pre-metamorphic C and O isotopic signatures in marbles subject to Pan-African granulite-facies metamorphism and U–Th mineralization (Tranomaro, Southeast Madagascar)  

Microsoft Academic Search

The status of fluid regimes during the Pan-African granulite-facies metamorphism in Southern Madagascar was examined by means of a mineralogical and stable isotope study of marble lithologies. In the granulitic Tranomaro area, which is made up of metasedimentary rocks (metapelitic, leptynitic (felsic) and calc–silicate metasediments) and intruded by syn-granulitic granitic bodies, syn-granulitic mineralization (Th–U) and metasomatic transformations (marbles?pyroxenites) demonstrate that

P. Boulvais; S. Fourcade; G. Gruau; B. Moine; M. Cuney

1998-01-01

373

La réhydratation orale par sonde gastrique est-elle plus efficace que la réhydratation orale par cuillère ? Étude préliminaire chez l’enfant atteint de déshydratation non sévère à l’hôpital Joseph-Raseta-Befelatanana, Madagascar  

Microsoft Academic Search

Résumé  Depuis sa recommandation par l’OMS, la solution de réhydratation orale (SRO) a contribué à la réduction de la mortalité imputée\\u000a aux gastroentérites de l’enfant. À Madagascar, les gastroentérites présentent un taux de létalité hospitalière de 3 %. La\\u000a réhydratation est réalisée classiquement avec une tasse ou une cuillère (C), dont l’efficacité peut être discutée en pratique\\u000a courante, compte tenu de

T. Ravelomanana; S. Rabeatoandro; N. Randrianaivo; A. Ratsimbazafy; H. Raobijaona; H. Barennes

2010-01-01

374

The geology, SHRIMP U Pb geochronology and metallogenic significance of the Ankisatra-Besakay District, Andriamena belt, northern Madagascar  

NASA Astrophysics Data System (ADS)

The Ankisatra-Besakay District (A-BD), located about 200 km north of Antananarivo and 75 km east of Maevatanana in central-northern Madagascar, hosts two historical mines, the Ankisatra Pb-Zn ± Au and Besakay Pb-Ag mines. These shear-hosted en echelon quartz veins at Besakay and deformed tensional quartz veins at Ankisatra produced a total of 4446 t of lead and 156 t of zinc in the early 1940s. In addition, there is Pb-Zn-Cu mineralisation in both quartz-feldspar leucosome veins/bands and metasomatised granulite-facies mafic orthogneiss, Cu-Zn and associated Fe-Mn mineralisation in magnetite-pyrite enderbite breccia, and Cu-Zn mineralisation in retrograde shear zones in granulite-facies paragneiss in the A-BD. The country rocks in the A-BD consist of amphibolite to granulite-facies mafic and granitoid orthogneisses and paragneisses with horizons of silicate-facies BIF. The paragneissic rocks in the district tectonically overlie the biotite-granitoid hornfels and sub-volcanic mangeritic rocks, which are separated from amphibolite-facies alkali-feldspar granitoid and enderbitic rocks by a major structure. The A-BD is structurally characterised by: (1) E-W-trending tensional fractures, quartz veins and dolerite dykes; (2) buckling-related axial-planar fractures; and (3) N-S, NE-SW and NNE-SSW trending dextral strike-slip shear zones, dolerite sills and quartz veins in transpressional extensional zones. Uranium-Pb SHRIMP II geochronology of zircon constrains the peak of magmatic, metamorphic, deformational and metasomatic events in the A-BD. An important constraint is whether hosting terranes contain signatures of the ca. 1690-1590 Ma critical age window for world-class BHT Pb-Zn-Ag deposits elsewhere in the world. At least two magmatic events are recorded from the A-BD. An early magmatic event is recorded by a 2725 ± 12 Ma single xenocrystic magmatic zircon in the >2676 ± 6 Ma precursor to the granulite-facies mafic orthogneiss. A ca. 2503-2460 Ma event is recorded by a 2465 ± 6 Ma minimum age of magmatism for the precursor to metasomatised granulite-facies mafic orthogneiss and 2483 ± 20 Ma for the precursor to biotite-granitoid hornfels. Zircons extracted from both the metasomatised and unaltered granulite-facies mafic orthogneisses record peak metamorphic ages of 2465 ± 12 and 2390 ± 10 Ma, probably representing compressional deformation, partial melting, and associated local magmatic events within the ca. 2475-2380 Ma period. Inherited zircons from the quartzo-feldspathic granulite-facies paragneisses return ages of protolithic supracrustal rocks ranging from ca. 2870 to 1700 Ma. A widespread period of rifting, anatectic magmatism, basic-ultrabasic and mangerite magmatism, and related granulite-facies metamorphism occurred between ca. 820 and 780 Ma. The possible exhalative units (silicate-facies BIF and metasomatic, garnet-quartz-plagioclase rock) are of late-Archaean to early-Palaeoproterozoic, rather than Mesoproterozoic age. The terrane lacks the critical evolution age window of ca. 1770-1550 Ma, characteristic of well-documented BHT Provinces in the Broken Hill Block and Mt. Isa Block, Australia and ca. 1959-1135 Ma from the Bushmanland Ore District, South Africa. This suggests that either such an event did not occur in the crust now forming the A-BD or that the equivalent supracrustal rocks containing these age signatures were eroded during Proterozoic times. It is less likely that the intense 780-820 Ma event destroyed evidence for their prior existence. The galenas from the Ankisatra and Besakay deposits have signatures characteristic of small-scale mineralised systems which derived most of their lead from local crustal rocks older than ca. >2.7 Ga. They are thus atypical of BHT deposits and associated vein-style mineralisation from well-endowed terranes. It is concluded that there are neither direct signs nor indirect temporal signals of giant stratiform/stratabound BHT Pb-Zn-Ag mineralisation, nor clear evidence for the presence of characteristic transitional sequences and alteration styles asso

Kabete, J.; Groves, D.; McNaughton, N.; Dunphy, J.

2006-05-01

375

A comparison of salivary pH in sympatric wild lemurs (Lemur catta and Propithecus verreauxi) at Beza Mahafaly Special Reserve, Madagascar.  

PubMed

Chemical deterioration of teeth is common among modern humans, and has been suggested for some extinct primates. Dental erosion caused by acidic foods may also obscure microwear signals of mechanical food properties. Ring-tailed lemurs at the Beza Mahafaly Special Reserve (BMSR), Madagascar, display frequent severe tooth wear and subsequent tooth loss. In contrast, sympatric Verreaux's sifaka display far less tooth wear and infrequent tooth loss, despite both species regularly consuming acidic tamarind fruit. We investigated the potential impact of dietary acidity on tooth wear, collecting data on salivary pH from both species, as well as salivary pH from ring-tailed lemurs at Tsimanampesotse National Park, Madagascar. We also collected salivary pH data from ring-tailed lemurs at the Indianapolis Zoo, none of which had eaten for at least 12 hr before data collection. Mean salivary pH for the BMSR ring-tailed lemurs (8.098, n=41, SD=0.550) was significantly more alkaline than Verreaux's sifaka (7.481, n=26, SD=0.458). The mean salivary pH of BMSR (8.098) and Tsimanampesotse (8.080, n=25, SD=0.746) ring-tailed lemurs did not differ significantly. Salivary pH for the Indianapolis Zoo sample (8.125, n=16, SD=0.289) did not differ significantly from either the BMSR or Tsimanampesotse ring-tailed lemurs, but was significantly more alkaline than the BMSR Verreaux's sifaka sample. Regardless of the time between feeding and collection of pH data (from several minutes to nearly 1 hr), salivary pH for each wild lemur was above the "critical" pH of 5.5, below which enamel demineralization occurs. Thus, the high pH of lemur saliva suggests a strong buffering capacity, indicating the impact of acidic foods on dental wear is short-lived, likely having a limited effect. However, tannins in tamarind fruit may increase friction between teeth, thereby increasing attrition and wear in lemurs. These data also suggest that salivary pH varies between lemur species, corresponding to broad dietary categories. PMID:18157845

Cuozzo, Frank P; Sauther, Michelle L; Yamashita, Nayuta; Lawler, Richard R; Brockman, Diane K; Godfrey, Laurie R; Gould, Lisa; Youssouf, Ibrahim Antho Jacky; Lent, Cheryl; Ratsirarson, Joelisoa; Richard, Alison F; Scott, Jessica R; Sussman, Robert W; Villers, Lynne M; Weber, Martha A; Willis, George

2008-04-01

376

Coat condition of ringtailed lemurs, Lemur catta at Berenty Reserve, Madagascar: I. Differences by age, sex, density and tourism, 1996-2006.  

PubMed

An index of coat condition can be a non-invasive tool for tracking health and stress at population level. Coat condition in ringtailed lemurs, Lemur catta, was recorded during September-November birth seasons of 1996, 1997, 1999, and 2001-2006 at Berenty Reserve, Madagascar. Condition was scored on a scale from 0: full, fluffy coat with guard hairs present, to 5: half or more of body hairless. Adult males did not differ overall from adult females. Coats were worse in adults than in 2-year-old subadults; 1-year-old juveniles were intermediate. Mothers and adult males lost coat condition as the season progressed: non-mother females maintained condition. Years 1999-2002 scored better coats than either 1996-1997 or 2003-2006. Lemurs in high population density areas had worse coats than in natural forest, but tourist presence had less effect than density. Monitoring coat condition in an apparently healthy population reveals differences between population segments, and in a forest fragment with limited immigration or emigration it can track progressive changes, correcting impressions of progressive improvement or degradation over time. Above all it gives a baseline for response to climate changes or eventual pathology. PMID:19051320

Jolly, Alison

2009-03-01

377

The Colposcopic Atlas of Schistosomiasis in the Lower Female Genital Tract Based on Studies in Malawi, Zimbabwe, Madagascar and South Africa  

PubMed Central

Background Schistosoma (S.) haematobium is a neglected tropical disease which may affect any part of the genital tract in women. Female genital schistosomiasis (FGS) may cause abnormal vaginal discharge, contact bleeding, genital tumours, ectopic pregnancies and increased susceptibility to HIV. Symptoms may mimic those typical of sexually transmitted infections (STIs) and women with genital schistosomiasis may be incorrectly diagnosed. An expert consensus meeting suggested that the following findings by visual inspection should serve as proxy indicators for the diagnosis of schistosomiasis of the lower genital tract in women from S. haematobium endemic areas: sandy patches appearing as (1) single or clustered grains or (2) sandy patches appearing as homogenous, yellow areas, or (3) rubbery papules. In this atlas we aim to provide an overview of the genital mucosal manifestations of schistosomiasis in women. Methodology/Principal findings Photocolposcopic images were captured from women, between 1994 and 2012 in four different study sites endemic for S. haematobium in Malawi, Zimbabwe, South Africa and Madagascar. Images and specimens were sampled from sexually active women between 15 and 49 years of age. Colposcopic images of other diseases are included for differential diagnostic purposes. Significance This is the first atlas to present the clinical manifestations of schistosomiasis in the lower female genital tract. It will be freely available for online use, downloadable as a presentation and for print. It could be used for training purposes, further research, and in clinical practice. PMID:25412334

Norseth, Hanne M.; Ndhlovu, Patricia D.; Kleppa, Elisabeth; Randrianasolo, Bodo S.; Jourdan, Peter M.; Roald, Borghild; Holmen, Sigve D.; Gundersen, Svein G.; Bagratee, Jayanthilall; Onsrud, Mathias; Kjetland, Eyrun F.

2014-01-01

378

Analysis of seed phorbol-ester and curcin content together with genetic diversity in multiple provenances of Jatropha curcas L. from Madagascar and Mexico.  

PubMed

Jatropha curcas L. has been promoted as an oilseed crop for use to meet the increased world demand for vegetable oil production, and in particular, as a feedstock for biodiesel production. Seed meal is a protein-rich by-product of vegetable oil extraction, which can either be used as an organic fertilizer, or converted to animal feed. However, conversion of J. curcas seed meal into animal feed is complicated by the presence of toxins, though plants producing "edible" or "non-toxic" seeds occur in Mexico. Toxins present in the seeds of J. curcas include phorbol esters and a type-I ribosome inactivating protein (curcin). Although the edible seeds of J. curcas are known to lack phorbol esters, the curcin content of these seeds has not previously been studied. We analyzed the phorbol ester and curcin content of J. curcas seeds obtained from Mexico and Madagascar, and conclude that while phorbol esters are lacking in edible seeds, both types contain curcin. We also analyzed spatial distribution of these toxins in seeds. Phorbol-esters were most concentrated in the tegmen. Curcin was found in both the endosperm and tegmen. We conclude that seed toxicity in J. curcas is likely to be due to a monogenic trait, which may be under maternal control. We also conducted AFLP analysis and conclude that genetic diversity is very limited in the Madagascan collection compared to the Mexican collection. PMID:21835630

He, Wei; King, Andrew J; Khan, M Awais; Cuevas, Jesús A; Ramiaramanana, Danièle; Graham, Ian A

2011-10-01

379

Household malaria knowledge and its association with bednet ownership in settings without large-scale distribution programs: Evidence from rural Madagascar  

PubMed Central

Background Insecticide–treated bednets are effective at preventing malaria. This study focuses on household–level factors that are associated with bednet ownership in a rural area of Madagascar which had not been a recipient of large–scale ITN distribution. Methods Data were gathered on individual and household characteristics, malaria knowledge, household assets and bednet ownership. Principal components analysis was used to construct both a wealth index based on household assets and a malaria knowledge index based on responses to questions about malaria. Bivariate and multivariate regressions were used to determine predictors of household bednet ownership and malaria knowledge. Results Forty–seven of 560 households (8.4%) owned a bednet. In multivariate analysis, higher level of malaria knowledge among household members was the only variable significantly associated with bednet ownership (odds ratio 3.72, P?

Krezanoski, Paul J.; Tsai, Alexander C.; Hamer, Davidson H.; Comfort, Alison B.; Bangsberg, David R.

2014-01-01

380

The common periwinkle, Littorina littorea , Linne, attracted by sugars  

Microsoft Academic Search

Summary In its natural habitat this marine snail was found to be very strongly attracted to an agar gel containing glucose. Sucrose and galactose were less but about equally attractive; manose barely attractive and fructose and manitol not attractive.

Richard G. Woodbridge

1978-01-01

381

Ecology and conservation of the crowned lemur, Lemur coronatus, at Ankarana, n. Madagascar. With notes on Sanford's lemur, other sympatrics and subfossil lemurs.  

PubMed

Forests of Ankarana limestone massif in northern Madagascar support one of the largest and least disturbed populations of Crowned Lemurs, Lemur coronatus. This paper reports a preliminary study of the ecology of this species in the Ankarana Special Reserve conducted at the end of the dry season in 1986, with additional information collected a year later. Crowned Lemurs occur in very high densities in the semi-deciduous canopy forest and this probably represents a dry season refuge for the species. They also use more open habitats, including sparsely vegetated limestone and degraded forest. Sanford's Lemur, Lemur fulvus sanfordi, also inhabits the Ankarana forests but is most abundant in degraded habitats. Crowned and Sanford's Lemurs had similar patterns of activity, which included nocturnal travelling and feeding bouts. Crowned Lemurs proved to be unusual among Lemur species in displaying low spatial troop cohesion and a lack of obvious troop hierarchy. Stronglyoides-like enteric helminths infested about one third of Crowned Lemurs but were apparently not causing disease. Crowned Lemurs fall prey to the Fosa, Cryptoprocta ferox, and the young possibly also to the largest raptors. A total of seven living lemur species (including the very rare Propithecus diadema perrieri and Daubentonia madagascariensis) were confirmed at Ankarana by the authors, and three further species have been reported by other observers. In addition to these ten extant lemurs, four subfossil species have been discovered: three of them (Hapalemur simus, Palaeopropithecus and Mesopropithecus) by the authors. The possibility that all 14 lemurs were once sympatric is discussed. For the present, the lemurs of Ankarana are protected from hunting by local taboo. Nevertheless they are under severe threat from habitat destruction, despite Ankarana's Special Reserve status. Given the very restricted distributions of Crowned and Sanford's Lemurs, both must be considered as threatened with extinction. PMID:2807091

Wilson, J M; Stewart, P D; Ramangason, G S; Denning, A M; Hutchings, M S

1989-01-01

382

Biology of mosquitoes that are potential vectors of Rift Valley Fever virus in different biotopes of the central highlands of Madagascar.  

PubMed

There were epidemic-epizootics of Rift Valley Fever (RVF) affecting humans and cattle in Madagascar in the district of Anjozorobe in 2008. Little is known about the role of Malagasy mosquitoes in the circulation of RVF virus. Therefore, we investigated the species diversity, dynamics and biology of potential RVF virus vectors in the rainforest, rainforest edge (village of Anorana), and savanna biotope (village of Antanifotsy) of this district between November 2008 and July 2010. We captured 56,605 adults of 35 different species. Anopheles squamosus (Theobald), Anopheles coustani (Laveran), Culex antennatus (Becker), Culex pipiens (L.), and Culex univittatus (Theobald) were the most abundant during the rainy season with Cx. pipiens the most abundant species in the rainforest (47%), and An. squamosus the most abundant species in the rainforest edge and in the savanna biotope (56%, 60%, respectively). Only Cx. univittatus was abundant in the dry season. The parous rate was > 60% throughout the rainy season for An. squamosus and it was > 50% from the middle to the end of the rainy season for Cx. pipiens. Two additional species have been found only at larval stage. Cattle were the most attractive bait for all species, followed by sheep and poultry. Human was the least attractive for all species. Most of the 163 bloodmeals tested were taken from cattle. Three were from poultry, one was from dog and one was a mixed bloodmeal taken from sheep and cattle. These results on vectorial capacity parameters may allow considering the involvement of mosquito transmission of the virus in the district of Anjozorobe during the recent epidemic-epizootic. PMID:23802456

Tantely, Michaël Luciano; Rakotoniaina, Jean-Claude; Tata, Etienne; Andrianaivolambo, Lala; Razafindrasata, Fidimanana; Fontenille, Didier; Elissa, Nohal

2013-05-01

383

Sources of tooth wear variation early in life among known-aged wild ring-tailed lemurs (Lemur catta) at the Bezà Mahafaly Special Reserve, Madagascar.  

PubMed

Ring-tailed lemurs (Lemur catta) at the Bezà Mahafaly Special Reserve (BMSR), Madagascar display a high frequency of individuals with notable and sometimes extreme tooth wear. Adult lemurs display a range of tooth wear even among individuals of the same age, but we do not know at what age this variation first appears. This study's goal was to determine whether wear variation occurs in younger wild lemurs. Based on the decade-long study of ring-tailed lemur feeding and dental ecology at BMSR, we hypothesized that younger, natal lemurs (under 5 years of age), would display variation in their degree of tooth wear that would correspond to microhabitat differences, given differences in food availability in different troops' home ranges. We also hypothesized that wear would differ between sexes at this young age, given differences in feeding between males and females in this population. Hypotheses were tested using dental topographic analyses using dental impressions collected from known-aged lemurs across 10 years at BMSR. Results illustrate significant differences in wear-related tooth topography (i.e., relief and slope, presented here as "occlusal lift") for microhabitat, sex and troop affiliation among lemurs under 5 years of age in this population. Although, all lemurs in this population consume mechanically challenging tamarind fruit, those in more disturbed habitats eat additional introduced foods, some of which are also mechanically challenging. Thus, dietary variation is the likely cause of variation in tooth wear. The wear variation we show at a young age suggests caution when assigning age based on tooth wear in living and fossil primates. These wear-related tooth shape changes early in life, which reflects sex, habitat variation and levels of anthropogenic disturbance, may potentially impact reproductive fitness later in life. Am. J. Primatol. 76:1037-1048, 2014. © 2014 Wiley Periodicals, Inc. PMID:24953664

Cuozzo, Frank P; Head, Brian R; Sauther, Michelle L; Ungar, Peter S; O'Mara, M Teague

2014-11-01

384

Three differentially expressed S-adenosylmethionine synthetases from Catharanthus roseus: molecular and functional characterization  

Microsoft Academic Search

We describe the molecular and functional characterization of three closely related S-adenosyl-L-methionine synthetase (SAMS) isoenzymes from Catharanthus roseus (Madagascar periwinkle). The genes are differentially expressed in cell cultures during growth of the culture and after application of various stresses (elicitor, nutritional down-shift, increased NaCl). Seedlings revealed organ-specific expression and differential gene regulation after salt stress. A relationship analysis indicated that

Gudrun Schröder; Johannes Eichel; Sabine Breinig; Joachim Schröder

1997-01-01

385

Feeding outside the forest: the importance of crop raiding and an invasive weed in the diet of gallery forest ring-tailed lemurs (Lemur catta) following a cyclone at the Beza Mahafaly special reserve, Madagascar.  

PubMed

In January 2005, a cyclone hit southern Madagascar, including the Beza Mahafaly Special Reserve, disrupting the flowering/fruiting cycle of Tamarindus indica, leaving Lemur catta without its major food resource during reproductive periods. We studied two adjacent groups of L. catta during the late gestation period, and both groups ventured outside the reserve to feed. The Red group (RG) fed daily on cultivated sweet potato (Ipomoea batatas) leaves in a nearby field, and both groups consumed leaves and stems of the invasive terrestrial flowering herb Mexican prickly poppy (Argemone mexicana), growing outside the reserve. The Green group (GG) spent significantly more time feeding than did RG, and more time feeding inside the forest compared to outside. The members of RG spent half of their time feeding in the crops, and nearly half of their diet consisted of easy-to-process sweet potato leaves. Additionally, RG defended and restricted GG's access to the crop territory. Of the two non-forest foods, A. mexicana leaves were higher in protein and most minerals (P, Mg, K and Na, but not Ca) and lower in fiber than sweet potato leaves, but sweet potato leaves were preferred by RG. L. catta is a markedly flexible primate with respect to diet, and switches to fallback foods from outside the forest during periods of low food availability. In the highly seasonal and unpredictable climate of southern Madagascar, such behavioral adaptations are important to the survival of this species. PMID:19776607

LaFleur, M; Gould, L

2009-01-01

386

A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar  

E-print Network

Abstract Background Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of...

Ricaut, Francois-X; Razafindrazaka, Harilanto; Cox, Murray P; Dugoujon, Jean-M; Guitard, Evelyne; Sambo, Clement; Mormina, Maru; Mirazon-Lahr, Marta; Ludes, Bertrand; Crubezy, Eric

2009-12-14

387

Toarcian–Kimmeridgian depositional cycles of the south-western Morondava Basin along the rifted continental margin of Madagascar  

Microsoft Academic Search

After rifting and final breakup of Gondwana along the former East-African-Antarctic Orogen during the Toarcian–Aalenian, passive\\u000a margins formed around the Proto-Indian Ocean. Sedimentological and stratigraphic studies in the southern Morondava Basin contribute\\u000a to an improved reconstruction of palaeoenvironmental changes during the syn-rift and post-rift margin formation. Depositional\\u000a models based on outcrop and literature data in combination with subsurface data sets

Markus Geiger; Günter Schweigert

2006-01-01

388

[The campaign against malaria in central western Madagascar: comparison of the efficacy of lambda-cyhalothrin and DDT house spraying. I--Entomological study].  

PubMed

For malaria vector control in Madagascar, the efficacy of lambda-cyhalothrin 10% wettable powder (ICON 10 WP) was compared with DDT 75% WP for house-spraying. This evaluation was conducted from November 1997 to September 1998 in highland villages of Vakinankaratra Region, at the fringe of the malaria epidemic zone, outside the zone covered by routine DDT house-spraying (Opération de pulvérisation intro-domiciliaire de DDT: OPID zone). Treatments were compared by house-spraying in four areas: 1) application of DDT 2g ai/m2 and 2) lambda-cyhalothrin 30 mg ai/m2 in previously unsprayed villages; 3) no intervention (control); 4) OPID 5th cycle of DDT 2g ai/m2. The prevalent vector Anopheles funestus almost disappeared from both the DDT and ICON sprayed areas, whereas in the unsprayed (control) area An. funeslus density went up to 60 females per room in April and there were two seasonal peaks of malaria transmission in January and March (see following paper). In the area sprayed with ICON, the parous rate of An. funestus decreased from 47% pre-spray to 39% six months post-spraying, while the parous rate increased in DDT-sprayed area (from 57% pre-spray to 64% six months post-spray). Bioassays of An. funestus on treated walls, six months post-spray, gave mortality rates of 100% on DDT and 90% on ICON. Conversely, ICON appeared to be more effective than DDT on thatched roofs (66% versus 100%, respectively, six months post-spray). In areas sprayed with DDT or ICON the density of An. arabiensis were little affected. This study demonstrated that, under equivalent conditions, both DDT and lambda-cyhalothrin were effective in reducing malaria transmission on the western fringes of the malaria epidemic zone of the malagasy highlands, with a residual effect lasting at least for six months. Lambda-cyhalothrin appeared to be more effective than DDT in reducing the longevity of malaria vectors. In addition to efficacy, the choice of insecticide for malaria vector control should take into account their acceptability by human populations and their toxicity and persistence in the environment. PMID:11802266

Brutus, L; Le Goff, G; Rasoloniaina, L G; Rajaonarivelo, V; Raveloson, A; Cot, M

2001-12-01

389

Determining areas that require indoor insecticide spraying using Multi Criteria Evaluation, a decision-support tool for malaria vector control programmes in the Central Highlands of Madagascar  

PubMed Central

Background The highlands of Madagascar present an unstable transmission pattern of malaria. The population has no immunity, and the central highlands have been the sites of epidemics with particularly high fatality. The most recent epidemic occurred in the 1980s, and caused about 30,000 deaths. The fight against malaria epidemics in the highlands has been based on indoor insecticide spraying to control malaria vectors. Any preventive programme involving generalised cover in the highlands will require very substantial logistical support. We used multicriteria evaluation, by the method of weighted linear combination, as basis for improved targeting of actions by determining priority zones for intervention. Results Image analysis and field validation showed the accuracy of mapping rice fields to be between 82.3% and 100%, and the Kappa coefficient was 0.86 to 0.99. A significant positive correlation was observed between the abundance of the vector Anopheles funestus and temperature; the correlation coefficient was 0.599 (p < 0.001). A significant negative correlation was observed between vector abundance and human population density: the correlation coefficient was -0.551 (p < 0.003). Factor weights were determined by pair-wise comparison and the consistency ratio was 0.04. Risk maps of the six study zones were obtained according to a gradient of risk. Nine of thirteen results of alert confirmed by the Epidemiological Surveillance Post were in concordance with the risk map. Conclusion This study is particularly valuable for the management of vector control programmes, and particularly the reduction of the vector population with a view to preventing disease. The risk map obtained can be used to identify priority zones for the management of resources, and also help avoid systematic and generalised spraying throughout the highlands: such spraying is particularly difficult and expensive. The accuracy of the mapping, both as concerns time and space, is dependent on the availability of data. Continuous monitoring of malaria transmission factors must be undertaken to detect any changes. A regular case notification allows risk map to be verified. These actions should therefore be implemented so that risk maps can be satisfactorily assessed. PMID:17261177

Rakotomanana, Fanjasoa; Randremanana, Rindra V; Rabarijaona, Léon P; Duchemin, Jean Bernard; Ratovonjato, Jocelyn; Ariey, Frédéric; Rudant, Jean Paul; Jeanne, Isabelle

2007-01-01

390

More than just talk: the framing of transactional sex and its implications for vulnerability to HIV in Lesotho, Madagascar and South Africa  

PubMed Central

Background 'Transactional sex' was regarded by the mid-1990s as an important determinant of HIV transmission, particularly in sub-Saharan Africa. Little attention has been paid to what the terms used to denote transactional sex suggest about how it is understood. This study provides a nuanced set of descriptions of the meaning of transactional sex in three settings. Furthermore, we discuss how discourses around transactional sex suggest linkages to processes of globalization and hold implications for vulnerability to HIV. Methods The analysis in this article is based on three case studies conducted as part of a multi-country research project that investigated linkages between economic globalization and HIV. In this analysis, we contextualize and contrast the 'talk' about transactional sex through the following research methods in three study sites: descriptions revealed through semi-structured interviews with garment workers in Lesotho; focus groups with young women and men in Antananarivo, Madagascar; and focus groups and in-depth interviews with young women and men in Mbekweni, South Africa. Results Participants' talk about transactional sex reveals two themes: (1) 'The politics of differentiation' reflects how participants used language to demarcate identities, and distance themselves from contextually-based marginalized identities; and (2) 'Gender, agency and power' describes how participants frame gendered-power within the context of transactional sex practices, and reflects on the limitations to women's power as sexual agents in these exchanges. Talk about transactional sex in our study settings supports the assertion that emerging transactional sexual practices are linked with processes of globalization tied to consumerism. Conclusions By focusing on 'talk' about transactional sex, we locate definitions of transactional sex, and how terms used to describe transactional sex are morally framed for people within their local context. We take advantage of an opportunity to comparatively explore such talk across three different study sites, and contribute to a better understanding of both emerging sexual practices and their implications for HIV vulnerability. Our work underlines that transactional sex needs to be reflected as it is perceived: something very different from, but of at least equal concern to, formal sex work in the efforts to curb HIV transmission. PMID:21961516

2011-01-01

391

Madagascar corals track sea surface temperature variability in the Agulhas Current core region over the past 334 years.  

PubMed

The Agulhas Current (AC) is the strongest western boundary current in the Southern Hemisphere and is key for weather and climate patterns, both regionally and globally. Its heat transfer into both the midlatitude South Indian Ocean and South Atlantic is of global significance. A new composite coral record (Ifaty and Tulear massive Porites corals), is linked to historical AC sea surface temperature (SST) instrumental data, showing robust correlations. The composite coral SST data start in 1660 and comprise 200 years more than the AC instrumental record. Numerical modelling exhibits that this new coral derived SST record is representative for the wider core region of the AC. AC SSTs variabilities show distinct cooling through the Little Ice Age and warming during the late 18(th), 19th and 20th century, with significant decadal variability superimposed. Furthermore, the AC SSTs are teleconnected with the broad southern Indian and Atlantic Oceans, showing that the AC system is pivotal for inter-ocean heat exchange south of Africa. PMID:24637665

Zinke, J; Loveday, B R; Reason, C J C; Dullo, W-C; Kroon, D

2014-01-01

392

Annual report 2005 Baobabs, Madagascar  

E-print Network

for three years - and some widely noted results, such as the discovery of an Ebola virus reservoir in bats capacities 28-29 Finding applications 30 Working for sustainable development 31 Sharing information-53 Information systems 54 Evaluation 54 Appendices Structure of the IRD 56 Central services 57 Research

393

Dinosaur Cannibal Unearthed in Madagascar  

NSF Publications Database

... Majungatholus atopus feeding from the remains of a conspecific. Majungatholus was an abelisaurid the ... also indication that Majungatholus fed on the remains of contemporary sauropods. including the ...

394

Vinca alkaloids.  

PubMed

Vinca alkaloids are a subset of drugs obtained from the Madagascar periwinkle plant. They are naturally extracted from the pink periwinkle plant, Catharanthus roseus G. Don and have a hypoglycemic as well as cytotoxic effects. They have been used to treat diabetes, high blood pressure and have been used as disinfectants. The vinca alkaloids are also important for being cancer fighters. There are four major vinca alkaloids in clinical use: Vinblastine (VBL), vinorelbine (VRL), vincristine (VCR) and vindesine (VDS). VCR, VBL and VRL have been approved for use in the United States. Vinflunine is also a new synthetic vinca alkaloid, which has been approved in Europe for the treatment of second-line transitional cell carcinoma of the urothelium is being developed for other malignancies. Vinca alkaloids are the second-most-used class of cancer drugs and will stay among the original cancer therapies. Different researches and studies for new vinca alkaloid applications will be carried out in this regard. PMID:24404355

Moudi, Maryam; Go, Rusea; Yien, Christina Yong Seok; Nazre, Mohd

2013-11-01

395

Vinca Alkaloids  

PubMed Central

Vinca alkaloids are a subset of drugs obtained from the Madagascar periwinkle plant. They are naturally extracted from the pink periwinkle plant, Catharanthus roseus G. Don and have a hypoglycemic as well as cytotoxic effects. They have been used to treat diabetes, high blood pressure and have been used as disinfectants. The vinca alkaloids are also important for being cancer fighters. There are four major vinca alkaloids in clinical use: Vinblastine (VBL), vinorelbine (VRL), vincristine (VCR) and vindesine (VDS). VCR, VBL and VRL have been approved for use in the United States. Vinflunine is also a new synthetic vinca alkaloid, which has been approved in Europe for the treatment of second-line transitional cell carcinoma of the urothelium is being developed for other malignancies. Vinca alkaloids are the second-most-used class of cancer drugs and will stay among the original cancer therapies. Different researches and studies for new vinca alkaloid applications will be carried out in this regard. PMID:24404355

Moudi, Maryam; Go, Rusea; Yien, Christina Yong Seok; Nazre, Mohd.

2013-01-01

396

Host resistance, population structure and the long-term persistence of bubonic plague: contributions of a modelling approach in the Malagasy focus.  

PubMed

Although bubonic plague is an endemic zoonosis in many countries around the world, the factors responsible for the persistence of this highly virulent disease remain poorly known. Classically, the endemic persistence of plague is suspected to be due to the coexistence of plague resistant and plague susceptible rodents in natural foci, and/or to a metapopulation structure of reservoirs. Here, we test separately the effect of each of these factors on the long-term persistence of plague. We analyse the dynamics and equilibria of a model of plague propagation, consistent with plague ecology in Madagascar, a major focus where this disease is endemic since the 1920s in central highlands. By combining deterministic and stochastic analyses of this model, and including sensitivity analyses, we show that (i) endemicity is favoured by intermediate host population sizes, (ii) in large host populations, the presence of resistant rats is sufficient to explain long-term persistence of plague, and (iii) the metapopulation structure of susceptible host populations alone can also account for plague endemicity, thanks to both subdivision and the subsequent reduction in the size of subpopulations, and extinction-recolonization dynamics of the disease. In the light of these results, we suggest scenarios to explain the localized presence of plague in Madagascar. PMID:23675291

Gascuel, Fanny; Choisy, Marc; Duplantier, Jean-Marc; Débarre, Florence; Brouat, Carine

2013-01-01

397

Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar.  

PubMed

In many mammalian species, the progressive wearing down of the teeth that occurs over an individual's lifetime has the potential to change dental function, jaw movements, or even feeding habits. The orientation of phase-I wear facets on molars reveals the direction of jaw movement during the power stroke of mastication. We investigated if and how molar wear facets change with increasing wear and/or age by examining a mixed longitudinal dataset of mandibular tooth molds from wild Propithecus edwardsi (N = 32 individuals, 86 samples). Measurements of the verticality of wear facets were obtained from three-dimensional digital models generated from ?CT scans. Results show that verticality decreases over the lifetime of P. edwardsi, a change that implies an increasingly lateral translation of the jaw as the teeth move into occlusion. A more transverse phase-I power stroke supports the hypothesis that these animals chew to maximize longevity and functionality of their teeth, minimizing the "waste" of enamel, while maintaining sharp shearing crests. Results of this study indicate that wear facet verticality is more closely correlated with age than overall amount of tooth wear, measured as area of exposed dentin, suggesting that age-related changes in cranial morphology may be more responsible for adjustments in jaw motion over the lifetimes of Propithecus than wear-related changes inthe shape of occluding teeth. Finally, the rate of decrease in wear facet verticality with age is greater in males than in females suggesting differences in development and/or access to resources between the sexes in this species. PMID:21805464

Blatch, Stephanie; Boyer, Doug M; King, Stephen J; Bunn, Jonathan M; Jernvall, Jukka; Wright, Patricia C

2011-09-01

398

The breakup of East Gondwana: Assimilating constraints from Cretaceous ocean basins around India into a best-fit tectonic model  

NASA Astrophysics Data System (ADS)

models for the Cretaceous seafloor-spreading history of East Gondwana result in unlikely tectonic scenarios for at least one of the plate boundaries involved and/or violate particular constraints from at least one of the associated ocean basins. We link East Gondwana spreading corridors by integrating magnetic and gravity anomaly data from the Enderby Basin off East Antarctica within a regional plate kinematic framework to identify a conjugate series of east-west-trending magnetic anomalies, M4 to M0 (~126.7-120.4 Ma). The mid-ocean ridge that separated Greater India from Australia-Antarctica propagated from north to south, starting at ~136 Ma northwest of Australia, and reached the southern tip of India at ~126 Ma. Seafloor spreading in the Enderby Basin was abandoned at ~115 Ma, when a ridge jump transferred the Elan Bank and South Kerguelen Plateau to the Antarctic plate. Our revised plate kinematic model helps resolve the problem of successive two-way strike-slip motion between Madagascar and India seen in many previously published reconstructions and also suggests that seafloor spreading between them progressed from south to north from 94 to 84 Ma. This timing is essential for tectonic flow lines to match the curved fracture zones of the Wharton and Enderby basins, as Greater India gradually began to unzip from Madagascar from ~100 Ma. In our model, the 85-East Ridge and Kerguelen Fracture Zone formed as conjugate flanks of a "leaky" transform fault following the ~100 Ma spreading reorganization. Our model also identifies the Afanasy Nikitin Seamounts as products of the Conrad Rise hotspot.

Gibbons, Ana D.; Whittaker, Joanne M.; Müller, R. Dietmar

2013-03-01

399

High-resolution Plate Reconstruction Models for the Central Indian Ocean Between Chrons 34 to 20 (83 to 42 Ma)  

NASA Astrophysics Data System (ADS)

The Indian Ocean is the result of East Gondwanaland fragmentation and dispersal since Jurassic. The complex seafloor spreading history of this region is related with several major events such as the Kerguelen and Reunion hotspot inception and the Indo-Eurasian collision. Indian and French scientists have collected a large amount of marine geophysical data in the conjugate basins of the northern and southern Indian Ocean, respectively. Using these data and under the auspices of an Indo-French collaborative project, we revisited the Central Indian (CIB), Crozet (CZB) and Madagascar (MDB) basins to understand their evolution. We created a common database consisting of magnetic data from 148 cruises belonging to the Indian and French scientists along with the so-called international data archived at NGDC. From these magnetic profiles, (1) we identified the anomalies using the inter-profile correlation and forward modelling as well as a detailed analysis of the characteristic shape of the anomalies (including the tiny wiggles); (2) we precisely located the magnetic isochrons using the analytic signal technique; and (3) we validated these isochrons by plate reconstructions. The analysis resulted in an updated magnetic isochrons map of the Central Indian, Crozet and Madagascar basins between chron 34ny (83 Ma) and chron 20ny (42.5 Ma), where the fracture zones were constrained by the satellite altimetry derived free air gravity anomaly map. The 1399 magnetic anomaly crossings (846, 287 and 266 picks from CIB, CZB, and MDB respectively) enabled us to estimate improved finite rotation parameters for Indian-Antarctic and Indian-African plate boundaries, which enabled preparation of better constrained high-resolution plate reconstruction models of the Central Indian Ocean for closer time intervals (~2 Ma). These magnetic anomaly picks and rotation parameters could also be used for a better tracing of the Indian Ocean Triple junction in the Central Indian Basin (CIB) and thereby defining the eastern and western parts of the CIB which are conjugate to the Crozet and Madagascar basins, respectively.

Yatheesh, V.; Dyment, J.; Bhattacharya, G. C.; Jensen, J.; Ramprasad, T.; Royer, J.-Y.; Kamesh Raju, K. A.; Patriat, P.; Choi, Y.

2009-04-01

400

Low autochtonous urban malaria in Antananarivo (Madagascar)  

PubMed Central

Background The study of urban malaria is an area undergoing rapid expansion, after many years of neglect. The problem of over-diagnosis of malaria, especially in low transmission settings including urban areas, is also receiving deserved attention. The primary objective of the present study was to assess the frequency of malaria among febrile outpatients seen in private and public primary care facilities of Antananarivo. The second aim was to determine, among the diagnosed malaria cases, the contribution of autochthonous urban malaria. Methods Two cross-sectional surveys in 43 health centres in Antananarivo in February 2003 (rainy season) and in July 2003 (dry season) were conducted. Consenting clinically suspected malaria patients with fever or history of fever in the past 48 hours were included. Malaria rapid diagnostic tests and microscopy were used to diagnose malaria. Basic information was collected from patients to try to identify the origin of the infection: autochthonous or introduced. Results In February, among 771 patients, 15 (1.9%) positive cases were detected. Three malaria parasites were implicated: Plasmodium. falciparum (n = 12), Plasmodium vivax (n = 2) and Plasmodium. ovale (n = 1). Only two cases, both P. falciparum, were likely to have been autochthonous (0.26%). In July, among 739 blood smears examined, 11 (1.5%) were positive: P. falciparum (n = 9) and P. vivax (n = 2). Three cases of P. falciparum malaria were considered to be of local origin (0.4%). Conclusion This study demonstrates that malaria cases among febrile episodes are low in Antananarivo and autochthonous malaria cases exist but are rare. PMID:16573843

Rabarijaona, Leon Paul; Ariey, Frederic; Matra, Robert; Cot, Sylvie; Raharimalala, Andrianavalona Lucie; Ranaivo, Louise Henriette; Le Bras, Jacques; Robert, Vincent; Randrianarivelojosia, Milijaona

2006-01-01

401

Antiproliferative Bistramides from Trididemnum cyclops from Madagascar  

PubMed Central

Bioassay-guided fractionation of a marine extract from Trididemnum cyclops afforded the new lipopeptide 39-oxobistramide K (1) and the known bistramides A (2) and D (3). Structure elucidation of 1 was carried out by analysis of one and two-dimensional NMR spectroscopy and HRMS data. Bistramides have been reported to exhibit antiproliferative activity in the nanomolar range against a number of tumor cell lines in vitro and in vivo. The isolate 1 was tested for antiproliferative activity against the A2780 cell line, and exhibited an IC50 value of 0.34 µM. PMID:19555084

Murphy, Brian T.; Cao, Shugeng; Brodie, Peggy; Maharavo, Jean; Andriamanantoanina, Hanta; Ravelonandro, Pierre; Kingston, David G.I.

2010-01-01

402

Madagascar Hissing Cockroaches: Information and Care  

E-print Network

, this insect is pri- marily a food source for larger animals such as lemurs, birds, and lizards. Worldwide. To avoid hurting the insect in this delicate stage, the cockroach should not be handled during this time months. He will leave it only for brief periods to obtain food and water. Female MHC are gregarious (form

Balasundaram, Balabhaskar "Baski"

403

Modeling  

NASA Technical Reports Server (NTRS)

A prediction of the future population of satellites, satellite fragments, and assorted spacecraft debris in Earth orbit can be reliably made only after three conditions are satisfied: (1) the size and spatial distributions of these Earth-orbiting objects are established at some present-day time; (2) the processes of orbital evolution, explosions, hypervelocity impact fragmentation, and atmospheric drag are understood; and (3) a reasonable traffic model for the future launch rate of Earth-orbiting objects is assumed. The theoretician will then take these three quantities as input data and will carry through the necessary mathematica and numerical analyses to project the present-day orbital population into the future.

Zook, H. A.

1985-01-01

404

Graphical Models in Computational Molecular  

E-print Network

Biology Organism Organs Tissues Cells Molecules Macro Molecules as Sequences SUGARS FATTY ACIDS AMINO ACIDS NUCLEOTIDES POLYSACCHARIDES FATS, LIPIDS, MEMBRANES PROTEINS NUCLEIC ACIDS (DNA, RNA) Building-tailed bat Jamaican fruit-eating bat Asiatic shrew Long-clawed shrew Mole Small Madagascar hedgehog Aardvark

Friedman, Nir

405

CathaCyc, a metabolic pathway database built from Catharanthus roseus RNA-Seq data.  

PubMed

The medicinal plant Madagascar periwinkle (Catharanthus roseus) synthesizes numerous terpenoid indole alkaloids (TIAs), such as the anticancer drugs vinblastine and vincristine. The TIA pathway operates in a complex metabolic network that steers plant growth and survival. Pathway databases and metabo