University of Antananarivo

About: University of Antananarivo is a education organization based out in Antananarivo, Madagascar. It is known for research contribution in the topics: Population & Lemur. The organization has 1561 authors who have published 1703 publications receiving 30922 citations. The organization is also known as: Tananarive University & Antananarivo University.

Run Distribution Over Flattened Partitions

Abstract: The study of flattened partitions is an active area of current research. In this paper, our study unexpectedly leads us to the OEIS numbers A124324. We provide a new combinatorial interpretation of these numbers. A combinatorial bijection between flattened partitions over $[n+1]$ and the partitions of $[n]$ is also given in a separate section. We introduce the numbers $f_{n, k}$ which count the number of flattened partitions over $[n]$ having $k$ runs. We give recurrence relations defining them, as well as their exponential generating function in differential form. It should be appreciated if its closed form is established. We extend the results to flattened partitions where the first $s$ integers belong to different runs. Combinatorial proofs are given.

Seed Banks in Savanna, Forest Fragments, and Continuous Forest Edges Differ in a Tropical Dry Forest in Madagascar

Abstract: Rapid deforestation has fragmented habitat across the landscape of Madagascar. To determine the effect of fragmentation on seed banks and the potential for forest regeneration, we sampled seed viability, density and diversity in 40 plots of 1 m2 in three habitat types: forest fragments, the near edge of continuous forest, and deforested savanna in a highly fragmented dry deciduous forest landscape in northwestern Madagascar. While seed species diversity was not different between forest fragments and continuous forest edge, the number of animal-dispersed seeds was significantly higher in forest fragments than in continuous forest edge, and this pattern was driven by a single, small-seeded species. In the savanna, seeds were absent from all but three of the 40 plots, indicating that regeneration potential is low in these areas. Several pre- and post-dispersal biotic and abiotic factors, including variation in the seed predator communities and edge effects could explain these findings. Understanding the extent to which seed dispersal and seed banks influence the regeneration potential of fragmented landscapes is critical as these fragments are the potential sources of forest expansion and re-connectivity. Resume Le sort de graines dispersees peut etre altere en reponse a la perte et la fragmentation d’ habitats, modifiant ainsi les banques de semences du sol. Nous avons echantillonne la viabilite, la densite et la diversite des graines dans 40 parcelles de 1 m2 en trois types d'habitats dans le paysage forestier feuillu, sec, et fragmente du nord-ouest de Madagascar: (1) fragments de foret (2) bords rapproches de foret ininterrompue, et (3) savane deboisee. Notre objectif etait d’etablir l'effet de cette fragmentation sur les banques de semences, et la possibilite de regeneration forestier. Nos resultats demontrent, bien que la diversite des especes de semences ne varie pas entre les fragments de foret et les bords rapproches de foret ininterrompue, que la quantite de graines dispersees par les animaux est considerablement plus elevee dans le premier type d'habitat que dans la deuxieme, et que cet effet est grâce a une seule espece [a petites graines]. Dans la savane deboisee, une absence complete de graines a ete notee dans tous les 40 parcelles, a part trois. Plusieurs facteurs biotiques ainsi qu’ abiotiques, pre- et post-dispersion, sont impliques, y compris des variations au sein des communautes de predateurs de graines ainsi que des effets de lisiere. Le potentiel de regeneration en paysages fragmentes repose sur une meilleure comprehension de la nature et l’etendue des changements dans la dispersion des graines, ainsi que les resultantes banques de semences. Ceci est particulierement important au Madagascar, ou la perte des forets se poursuit a un rythme precipite, puisque ces fragments sont les sources essentielles de l'expansion et de la reconnexion forestiere.

Restructuring extended Lexical elaborate Language

Abstract: Requirements engineering is a process that explores the objectives of the actors and the activities to achieve their objectives, meeting requirements. The use of the natural language oriented requirement model as eLEL is interesting in order to specify the requirements and represent the conceptual level of a system. However, the typing of attributes and the representation of the method of a system that the eLEL model describes do not conform to the rule imposed by Object-Oriented Programming to type an attribute and construct a method. But we thought that the information that constitutes them is already described in the universe of discourse (UofD). Our strategy is to extend eLEL in its conceptual representation and the new extended lexicon is called ReLEL. To achieve this, we have added new method concepts to the ReLEL metamodel and extended the attribute format to obey the rule imposed by Object Oriented Programming (POO). Nevertheless, to validate the proposed approach, we evaluated the attribute and method performance of both eLEL and ReLEL requirements models. As a result, we have found that the ReLEL model has more attribute and method level elements than the eLEL model. Therefore, we have proposed an approach to derive a UML class diagram conceptual model from the ReLEL requirement model.

A comparison of the effectiveness of methods of deterring pteropodid bats from feeding on commercial fruit in Madagascar

Abstract: We compared the effectiveness of methods of deterring Pt eropus ru fus from feeding on commercial fruit in east central and southeastern Madagascar in 2012–2013 during the Li t chi chinensis harvest. Two of the three methods used, installing plastic flags and ringing bells in the trees, were derived from those used by litchi growers in the southeast. We improved and standardized these methods and compared their effectiveness with an organic product made from dried blood and vegetable oil (Plantskydd®) with a taste and odour aimed at deterring mammal feeding. The bats damaged from 440–7,040 g of litchi fruits per tree and two of the three methods reduced the fruit lost to bats: the plastic flags and the organic deterrent. There were significant differences in the damage levels between the study sites and between our three methods of deterrence. The plastic flags and bell ringing methods were significantly less effective in reducing the fruit bat damage compared to the taste deterrent. The latter was most effective when it had enough time to dry and adhere to the fruits after spraying and before rain. Its effectiveness was further demonstrated in flight cage experiments during which Ro us ett u s madagas cariens is avoided litchis treated with Plantskydd®. Analysis of bat faecal samples revealed no feeding preference but the collected samples contained large numbers of Ficu s seeds, suggesting that the bats feed extensively on Ficu s fruits rather than on fruit of economic importance. Apart from fruit ripeness, tree productivity or other phenological factors did not affect the amount of fruit eaten by the bats. More fruits were damaged by birds than bats at both study sites.

Extensive variability in the gut microbiome of a highly-specialized and critically endangered lemur species across sites.

Abstract: Deforestation continues to jeopardize Malagasy primates as viable habitats become smaller, more fragmented, and more disturbed. This deforestation can lead to changes in diet, microhabitat, and gene flow between populations of endangered species, and it remains unclear how these changes may affect gut microbiome (GM) characteristics. The black-and-white ruffed lemur (Varecia variegata), which is among Madagascar's most threatened lemur species, provides a critical model for understanding the relationships between historical and on-going deforestation (habitat disturbance), feeding ecology, and GM composition and diversity. We studied four populations inhabiting two rainforests (relatively pristine vs. highly disturbed) in southeastern Madagascar. We conducted full-day focal animal behavioral follows and collected fecal samples opportunistically across a three-month period. Our results indicate that lemurs inhabiting sites characterized by habitat disturbance and low dietary diversity exhibited reduced gut microbial alpha diversity. We also show that these same factors were associated with high community dissimilarity using weighted and unweighted UniFrac metrics. Finally, an indicator species analysis showed that the most pristine site was characterized by an abundance of methanogenic archaea. While it is impossible to disentangle the relative contributions of each confounding variable presented by our sampling design, these results provide crucial information about GM variability, thereby underscoring the importance of monitoring endangered species at the population-level.