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The metacommunity concept provides a theoretical framework that aims at explaining organism distributions by a combination of environmental filtering, dispersal, and drift. However, few works have attempted a multitaxon approach and even fewer have compared two distant biogeographical regions using the same methodology. We tested the expectation that temperate (mediterranean-climate) pond metacommunities would be more influenced by environmental and spatial processes than tropical ones, because of stronger environmental gradients and a greater isolation of waterbodies. However, the pattern should be different among groups of organisms depending on their dispersal abilities. We surveyed 30 tropical and 32 mediterranean temporary ponds from Costa Rica and Spain, respectively, and obtained data on 49 environmental variables. We characterized the biological communities of bacteria and archaea (from the water column and the sediments), phytoplankton, zooplankton, benthic invertebrates, amphibians and birds, and estimated the relative role of space and environment on metacommunity organization for each group and region, by means of variation partitioning using generalized additive models. Purely environmental effects were important in both tropical and mediterranean ponds, but stronger in the latter, probably due to their larger limnological heterogeneity. Spatially correlated environment and pure spatial effects were greater in the tropics, related to higher climatic heterogeneity and dispersal processes (e.g., restriction, surplus) acting at different scales. The variability between taxonomic groups in the contribution of spatial and environmental factors to metacommunity variation was very wide, but higher in active, compared with passive, dispersers. Higher environmental effects were observed in mediterranean passive dispersers, and higher spatial effects in tropical passive dispersers. The unexplained variation was larger in the tropical setting, suggesting a higher role for stochastic processes, unmeasured environmental factors, or biotic interactions in the tropics, although this difference affected some actively dispersing groups (insects and birds) more than passive dispersers. These results, despite our limitations in comparing only two regions, provide support, for a wide variety of aquatic organisms, for the classic view of stronger abiotic niche constraints in temperate areas compared with the tropics. The heterogeneous response of taxonomic groups between regions also points to a stronger influence of regional context than organism adaptations on metacommunity organization.

The subgenus Tityus (Archaeotityus) includes small variegated species considered until recently, a basal group within Tityus, one of the most diverse and medically relevant genera of scorpions in the New World. Archaeotityus species are distributed in the humid forests of Lower Central America and the Choco, Guiana Shield, and Amazon regions. Due to their size and habits, Archaeotityus species are not usually considered dangerous, however, there are some clinical reports that show otherwise. To contribute to the toxinological knowledge of these poorly explored species, we characterized the venom of Tityus ocelote from three localities in Costa Rica. In addition, we assessed the evolutionary relationships of putative sodium channel modulating peptides found in this species with those reported for other members of the genus, through a maximum likelihood phylogenetic analysis based on their amino acid sequences. We observed the presence of homologs of previously identified NaTx from the species T. (Archaeotityus) clathratus and some other putative Na + and K + channel modulating peptides related to the T. bahiensis group. In addition, we sequenced some peptides related to toxins present in the venom of the subgenus Atreus, such as those reported T. obscurus, T. pachyurus, and the Costa Rican endemic species T. dedoslargos. Our phylogenetic analysis suggests that the venom of this Archaeotityus species is very complex and that some of the ion channel toxins expressed in it are related to distinct lineages within the genus Tityus, which could represent a plesiomorphic condition conserved in this group of scorpions of the New World.

Entre 2017 y 2018 se realizó un estudio limnológico de 30 lagunas temporales de Costa Rica. Entre otros organismos, se estudiaron las esponjas de agua dulce (Porifera: Spongillidae), en cuya distribución se centra el presente estudio. De las muestras se aislaron 15 552 gémulas de esponjas repartidas en 21 localidades de la provincia de Guanacaste. Este material se obtuvo a lo largo de seis campañas de muestreo efectuadas entre mayo de 2017 y diciembre de 2018. Las especies de esponjas identificadas fueron Radiospongilla crateriformis (Potts, 1882), Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974), Tubella variabilis Bonetto & Ezcurra de Drago, 1973 y Ephydatia fluviatilis (Linnaeus, 1759) con nuevas localidades. Se recolectaron las cuatro especies juntas en una laguna denominada “El Sitio” y se citan dos nuevas localidades de T. variabilis en “Sainalosa” y “El Sitio” junto con Ephydatia fluviatilis y Corvoheteromeyenia heterosclera en la primera, ambas lagunas localizadas en la provincia de Guanacaste. Además, destaca la recolección de gémulas de T. variabilis aglutinadas en el tubo de alojamiento del oligoqueto Aulophorus vagus Leidy, 1880 (Annelida: Oligochaeta: Naididae). Todas las gémulas se recolectaron únicamente en la vertiente Pacífica de Costa Rica, mientras que no se encontró ninguna en las lagunas muestreadas en la vertiente Atlántica, correspondiéndose con una mayor disponibilidad de fitoplancton en la primera, y mayor transparencia y menor concentración de sales del agua en la segunda.

2 páginas y 1 figura. Corrigendum del registro: http://hdl.handle.net/10261/256298, We report the first proteomics analyses of the venoms of two poorly studied snakes, the Manabi hognosed pitviper Porthidium arcosae endemic to the western coastal province of Manabí (Ecuador), and the Costa Rican hognosed pitviper P. volcanicum with distribution restricted to South Pacific Costa Rica and western Panamá. These venom proteomes share a conserved compositional pattern reported in four other congeneric species within the clade of South American Porthidium species, P. nasutum, P. lansbergii, P. ophryomegas, and P. porrasi. The paraspecific immunorecognition profile of antivenoms produced in Costa Rica (ICP polyvalent), Perú (Instituto Nacional de Salud) and Brazil (soro antibotrópico pentavalente, SAB, from Instituto Butantan) against the venom of P. arcosae was investigated through a third-generation antivenomics approach. The maximal venom-binding capacities of the investigated antivenoms were 97.1 mg, 21.8 mg, and 25.7 mg of P. arcosae venom proteins per gram of SAB, ICP, and INS-PERU antibody molecules, respectively, which translate into 28.4 mg, 13.1 mg, and 15.2 mg of total venom proteins bound per vial of SAB, ICP, and INS-PERU AV. The antivenomics results suggest that 21.8%, 7.8% and 6.1% of the SAB, ICP, and INS-PERU antibody molecules recognized P. arcosae venom toxins. The SAB antivenom neutralized P. arcosae venom's lethality in mice with an ED50 of 31.3 mgV/g SAB AV. This preclinical neutralization paraspecificity points to Brazilian SAB as a promising candidate for the treatment of envenomings by Ecuadorian P. arcosae. BIOLOGICAL SIGNIFICANCE: Assessing the preclinical efficacy profile of antivenoms against homologous and heterologous medically relevant snake venoms represents an important goal towards defining the biogeographic range of their clinical utility. This is particularly relevant in regions, such as Mesoamerica, where a small number of pharmaceutical companies produce antivenoms against the venoms of a small number of species of maximum medical relevance among the local rich herpetofauna, leaving a wide range of snakes of secondary medical relevance, but also causing life-threatening human envenomings without nominal clinical coverage. This work is part of a larger project aiming at mapping the immunological characteristics of antivenoms generated in Latin American countries towards venoms of such poorly studied snakes of the local and neighboring countries' herpetofauna. Here we report the proteomics characterization of the Manabi hognosed pitviper Porthidium arcosae endemic to the western coastal province of Manabí (Ecuador), and the Costa Rican hognosed pitviper P. volcanicum with distribution restricted to southwestern Costa Rica, the antivenomics assessment of three bothropoid commercial antivenoms produced in Costa Rica, Perú, and Brazil against the venom components of P. arcosae, and the in vivo capacity of the Brazilian soro antibotrópico pentavalente (SAB) from Instituto Butantan to neutralize the murine lethality of P. arcosae venom. The preclinical paraspecific ED50 of 31.3 mg of P. arcosae venom per gram of antivenom points to Brazilian SAB as a promising candidate for the treatment of envenomings by the Manabi hognosed pitviper P. arcosae., This study was partly supported by grant EFP-00021744 financed by Fundaç ̃ao Rondˆonia de Amparo ao Desenvolvimento das Aç ̃oes Cien- tíficas e Tecnol ́ogicas (FAPERO, Rondˆonia, Brazil). Research performed at IBV-CSIC was partially funded by grant BFU2017-89103-P from the Ministerio de Ciencia e Innovaci ́on, Madrid, Spain. Work performed at Instituto Clodomiro Picado was supported by Vicerrectoría de Inves- tigaci ́on (741-C0-071) and Vicerrectoría de Acci ́on Social (Proyecto ED- 3248) of Universidad de Costa Rica. The excellent bench work assistance of Sarai Quesada-Bernat with antivenomics, and Yania Rodríguez Jim ́enez with determination of the murine LD50 for P. arcosae venom and neutralization of its lethal effect by the Brazilian pentavalent bothropic antivenom, are gratefully acknowledged

Coralsnakes belong to the family Elapidae and possess venoms which are lethal to humans and can be grouped based on the predominance of either three finger toxins (3FTxs) or phospholipases A

The genus Porthidium includes nine pitviper species inhabiting Mexico, Central America, and northern South America. Porthidium porrasi is a species endemic to the Southwest of Costa Rica, for which no information on its venom was available. In this study, the proteomic composition and functional activities of P. porrasi venom are described. The most abundant venom proteins were identified as metalloproteinases (36.5%). In descending order of abundance, proteins belonging to the disintegrin, phospholipase A2, serine proteinase, C-type lectin/ lectin-like, vascular endothelial growth factor, Cysteine-rich secretory protein, L-amino acid oxidase, phospholipase B, and phosphodiesterase families were also identified. P. porrasi venom showed a weak lethal potency in mice (10 μg/g body weight by intraperitoneal route), induced marked hemorrhage and edema, and weak myotoxic effect. These in vivo activities, as well as those assayed in vitro (proteolytic and phospholipase A2 activities) correlated with compositional data. A comparison of P. porrasi venom with those of three other Porthidium species studied to date reveals a generally conserved compositional and functional pattern in this pitviper genus. Importantly, the lethal effect of P. porrasi venom in mice was adequately cross-neutralized by a heterospecific polyvalent antivenom, supporting its use in the treatment of eventual envenomings by this species. Universidad de Costa Rica/[741-B7-608]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

non-buthid venoms, for which knowledge is scarce. In this work, we characterized the venom of a Diplocentridae species, Didymocentrus krausi, a small fossorial scorpion that inhabits the Tropical Dry Forest of Central America. D. krausi venom soluble fraction contains proteases with enzymatic activity on gelatin and casein. Mass spectrometry and venomic analysis confirmed the presence of elastase-like, cathepsin-O-like proteases and a neprilysin- like metalloproteinase. We did not detect phospholipase A2, C or D, nor hyaluronidase activity in the venom. By homology-based venom gland transcriptomic analysis, NDBPs, a β-KTx-like peptide, and other putative toxin transcripts were found, which, together with a p-benzoquinone compound present in the venom, could potentially explain its direct hemolytic and cytotoxic effects in several mammalian cell lines. Cytotoxicity of D. krausi venom was higher than the effect of venoms from two buthid scorpion species distributed in Costa Rica, Centruroides edwardsii and Tityus pachyurus. Even though D. krausi venom was not lethal to mice or crickets, when injected in mouse gastrocnemius muscle at high doses it induced pathological effects at 24 h, which include myonecrosis, weak hemorrhage, and inflammatory infiltration. We observed an apparent thrombotic effect in the skin blood vessels, but no in vitro fibrinogenolytic activity was detected. In crickets, D. krausi venom induced toxicity and paralysis in short periods of time Universidad de Costa Rica/[741-B8-133]/UCR/Costa Rica Universidad de Costa Rica/[741-A5-048]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicina UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA)

16 páginas, 7 figuras., Snakebite envenoming is a neglected tropical disease that may claim over 100,000 human lives annually worldwide. Snakebite occurs as the result of an interaction between a human and a snake that elicits either a defensive response from the snake or, more rarely, a feeding response as the result of mistaken identity. Snakebite envenoming is therefore a biological and, more specifically, an ecological problem. Snake venom itself is often described as a "cocktail", as it is a heterogenous mixture of molecules including the toxins (which are typically proteinaceous) responsible for the pathophysiological consequences of envenoming. The primary function of venom in snake ecology is pre-subjugation, with defensive deployment of the secretion typically considered a secondary function. The particular composition of any given venom cocktail is shaped by evolutionary forces that include phylogenetic constraints associated with the snake's lineage and adaptive responses to the snake's ecological context, including the taxa it preys upon and by which it is predated upon. In the present article, we describe how conceptual frameworks from ecology and evolutionary biology can enter into a mutually enlightening relationship with clinical toxinology by enabling the consideration of snakebite envenoming from an "ecological stance". We detail the insights that may emerge from such a perspective and highlight the ways in which the high-fidelity descriptive knowledge emerging from applications of -omics era technologies - "venomics" and "antivenomics" - can combine with evolutionary explanations to deliver a detailed understanding of this multifactorial health crisis., Studies by JJC’s research group cited in this review were partially funded by grants from the Ministerio de Ciencia e Innovacion, ´ Madrid, Spain (BMC 2004-01432, BFU 2007-61563, BFU 2010-173730, BFU 2013-42833-P, and BFU 2017-89103-P). JJC wants to acknowledge and heartly thank all the researchers and collaborators of these projects who contributed laboratory work and numerous hours of scientific discussions. EABU was supported by a Norwegian Research Council FRIPROYRT Fellowship no. 287462. TNWJ was supported by National Health and Medical Research Grant 13/093/002 AVRU. KS was supported by DBT / Wellcome Trust India Alliance Fellowship (IA/I/19/2/504647). Support by Vicerrectoría de Investigacion ´ (University of Costa Rica) to work performed at Instituto Clodomiro Picado is also gratefully acknowledged.

The metacommunity concept provides a theoretical framework that aims at explaining organism distributions by a combination of environmental filtering, dispersal and drift. With the development of statistical tools to quantify and partially isolate the role of each of these processes, empirical metacommunity studies have multiplied worldwide. However, few works attempt a multi-taxon approach and even fewer compare two distant biogeographical regions using the same methodology. Under this framework, we tested the expectation that temperate (mediterranean-climate) pond metacommunities would be more influenced by environmental and spatial processes than tropical ones, because of stronger environmental gradients and greater isolation of waterbodies.We surveyed 30 tropical and 32 mediterranean temporary ponds from Costa Rica and Spain, respectively, and obtained data on 49 environmental variables (including limnological, hydrogeomorphological, biotic, climatic, and landscape variables). We characterized the biological communities of Bacteria and Archaea (from both the water column and the sediments), phytoplankton, zooplankton, benthic invertebrates, amphibians and birds, and estimated the relative role of space and environment on metacommunity organization for each group and region, by means of variation partitioning using Generalized Additive Models (GAMs).Environmental selection was important in both tropical and mediterranean ponds, but markedly stronger in the latter, probably due to their larger limnological heterogeneity. Spatialized environment and pure spatial effects were greater in the tropics, related to higher climatic heterogeneity and dispersal processes (e.g. restriction, surplus) acting at different scales. The variability between taxonomic groups in spatial and environmental contributions was very wide. Effects on passive and active dispersers were similar within regions but different across regions, with higher environmental effects in mediterranean active dispersers. The residual (unexplained) variation was larger in tropical pond metacommunities, suggesting a higher role for stochastic processes and/or effects of biotic interactions in the tropics. Overall, these results provide support, for a wide variety of organisms related to aquatic habitats, for the classical view of stronger abiotic niche constraints in temperate areas compared to the tropics.

We report the first proteomics analyses of the venoms of two poorly studied snakes, the Manabi hognosed pitviper Porthidium arcosae endemic to the western coastal province of Manabí (Ecuador), and the Costa Rican hognosed pitviper P. volcanicum with distribution restricted to South Pacific Costa Rica and western Panamá. These venom proteomes share a conserved compositional pattern reported in four other congeneric species within the clade of South American Porthidium species, P. nasutum, P. lansbergii, P. ophryomegas, and P. porrasi. The paraspecific immunorecognition profile of antivenoms produced in Costa Rica (ICP polyvalent), Perú (Instituto Nacional de Salud) and Brazil (soro antibotrópico pentavalente, SAB, from Instituto Butantan) against the venom of P. arcosae was investigated through a third-generation antivenomics approach. The maximal venom-binding capacities of the investigated antivenoms were 97.1 mg, 21.8 mg, and 25.7 mg of P. arcosae venom proteins per gram of SAB, ICP, and INS-PERU antibody molecules, respectively, which translate into 28.4 mg, 13.1 mg, and 15.2 mg of total venom proteins bound per vial of SAB, ICP, and INS-PERU AV. The antivenomics results suggest that 21.8%, 7.8% and 6.1% of the SAB, ICP, and INS-PERU antibody molecules recognized P. arcosae venom toxins. The SAB antivenom neutralized P. arcosae venom's lethality in mice with an ED50 of 31.3 mgV/g SAB AV. This preclinical neutralization paraspecificity points to Brazilian SAB as a promising candidate for the treatment of envenomings by Ecuadorian P. arcosae. Biological significance: Assessing the preclinical efficacy profile of antivenoms against homologous and heterologous medically relevant snake venoms represents an important goal towards defining the biogeographic range of their clinical utility. This is particularly relevant in regions, such as Mesoamerica, where a small number of pharmaceutical companies produce antivenoms against the venoms of a small number of species of maximum medical relevance among the local rich herpetofauna, leaving a wide range of snakes of secondary medical relevance, but also causing life-threatening human envenomings without nominal clinical coverage. This work is part of a larger project aiming at mapping the immunological characteristics of antivenoms generated in Latin American countries towards venoms of such poorly studied snakes of the local and neighboring countries' herpetofauna. Here we report the proteomics characterization of the Manabi hognosed pitviper Porthidium arcosae endemic to the western coastal province of Manabí (Ecuador), and the Costa Rican hognosed pitviper P. volcanicum with distribution restricted to southwestern Costa Rica, the antivenomics assessment of three bothropoid commercial antivenoms produced in Costa Rica, Perú, and Brazil against the venom components of P. arcosae, and the in vivo capacity of the Brazilian soro antibotrópico pentavalente (SAB) from Instituto Butantan to neutralize the murine lethality of P. arcosae venom. The preclinical paraspecific ED50 of 31.3 mg of P. arcosae venom per gram of antivenom points to Brazilian SAB as a promising candidate for the treatment of envenomings by the Manabi hognosed pitviper P. arcosae., This study was partly supported by grant EFP-00021744 financed by Fundação Rondônia de Amparo ao Desenvolvimento das Ações Científicas e Tecnológicas (FAPERO, Rondônia, Brazil). Research performed at IBV-CSIC was partially funded by grant BFU2017-89103-P from the Ministerio de Ciencia e Innovación, Madrid, Spain. Work performed at Instituto Clodomiro Picado was supported by Vicerrectoría de Investigación (741-C0-071) and Vicerrectoría de Acción Social (Proyecto ED-3248) of Universidad de Costa Rica.

10 páginas, 3 figuras, 1 tabla. Dispone de material suplementario en: https://doi.org/10.1016/j.jprot.2020.103882, The Duvernoy's gland secretory proteome of the false coral snake Rhinobothryum bovallii (Costa Rica), unveiled applying bottom-up venomics, comprises a handful of toxins belonging to only three protein families, three-finger toxin (3FTx), cysteine-rich secretory protein (CRISP), and snake venom metalloprotease (PIII-SVMP). Except for small differences in the relative abundance of the PIII-SVMPs, which may be due to individual variability, no evidence of geographic variability or ontogenetic changes was found among the venom proteomes of the juvenile and adult R. bovallii snakes sampled. Major monomeric (86.5%mol) and minor dimeric (2.8%mol) 3FTxs dominate the toxin arsenal of the Costa Rican false coral snake. The remaining 10.7% of the venom proteome comprises CRISP (8.2%) and PIII-SVMP (2.4%) molecules. In vivo lethality assays showed that R. bovallii produces venom that is non-toxic towards mammalian prey, and which exerts a different toxic effect on domestic chicken chicks and baby green iguana. Toxicovenomic analysis of R. bovallii venom in the iguana model identified two 3FTx RP-HPLC fractions that faithfully mimicked the irreversible immobilizing effect of the whole venom. BIOLOGICAL SIGNIFICANCE: With more than 2200 species in family Colubridae (sensu lato), rear-fanged snakes comprise approximately two-thirds of the extant species of advanced snakes. Snakebites from venomous snakes that are of medical concern are predominantly from front-fanged snakes of families Viperidae and Elapidae. On the other hand, rear-fanged snakes have been conventionally considered non-venomous, and thus their venoms have remained a largely untapped area of venomics. However, increasing documentation of life-threadening, even fatal, envenomings from rear-fanged snakes has sparked interest in their venoms. Appying bottom-up venomics we have revealed that the Duvernoy's gland secretory proteome of R. bovallii comprises a handful of toxins belonging to only three protein families, with slow-acting three-finger toxins (3FTx) that are non-toxic towards mammalian prey and show preference towards diapsid taxa representing the dominant structural and functional proteins. Our work documents for the first time 3FTxs exerting different effect in an avian model than in a reptile model. Besides, the 3FTx fractions that faithfully mimicked the irreversible iguana-immobilizing effect of the whole venom were identified through toxicovenomic analysis of R. bovallii venom on Iguana iguana. Our work underscores the importance of using biologically-relevant animal toxicity models for investigating the biological roles of venoms in an evolutionary-ecological context., This study was partly supported by grant BFU2017-89103-P from the Ministerio de Ciencia, Innovación y Universidades, Madrid (Spain) to JJC. The authors gratefully acknowledge the excellent bench assistance of Stephanie Chaves and Julián Fernández, Instituto Clodomiro Picado, UCR, and Andres Vega for sharing his R. bovalli photographs.

Rear-fanged colubrid snakes include hundreds of species globally that possess a Duvernoy's venom gland and often one-several enlarged rear maxillary teeth. We investigated the venom proteome of the Central American Lyre Snake (Trimorphodon quadruplex), a moderate-sized rear-fanged colubrid snake and the southernmost Trimorphodon, using a bottom-up proteomic approach coupled with enzyme and inhibitor assays, cytotoxicity assays and lethal toxicity assays. Several enzymes uncommonly observed in colubrid venoms were purified and characterized further. Trimorphodon quadruplex has a rather low complexity venome, typical of many rear-fanged snakes, but its venom contains L-amino acid oxidase, phospholipase A2, and a dimeric 3FTx, and 3FTxs dominate the proteome. Its PLA2 is catalytically quite active, but it lacks myotoxicity or acute toxicity; LAAO exhibits conserved structure and appears to be highly labile. Several P-III metalloproteinases are present and hydrolyze azocasein and the α-subunit of fibrinogen but lack hemorrhagic activity. Trimorphodon quadruplex produces venom and retains constriction, utilizing both chemically-mediated and mechanical feeding modes. SIGNIFICANCE: We demonstrate that T. quadruplex venom proteins are similar to those found in front-fanged snake species are present but show different biological activities. Our results underscore the importance of considering the biological roles of venoms from more than a mammal-centric perspective.

Scorpions of the Neotropical genus Tityus are responsible for most severe envenomations in the Caribbean, South America, and Lower Central America (LCA). Although Tityus is taxonomically complex, contains high toxin polymorphism, and produces variable clinical manifestations, treatment is limited to antivenoms produced against species with restricted distributions. In this study, we explored the compositional and antigenic diversity of Tityus venoms to provide improved guidelines for the use of available antivenoms at a broader geographic scale. We used immunoblotting, competitive ELISA, and in vivo studies to compare reactivity against commercial antivenoms from Brazil, Venezuela, and Mexico, as well as MALDI-TOF mass spectrometry, cDNA sequencing, and phylogenetic analyses to assess venom sodium channel-active toxin (NaTx) content from medically important Tityus populations inhabiting Brazil, Colombia, Costa Rica, Ecuador, Panama, Trinidad and Tobago, and Venezuela. Additionally, we raised rabbit antibodies against Tityus venoms from LCA to test for cross-reactivity with congeneric species. The results suggest that Tityus spp. possess high venom antigenic diversity, underlying the existence of four toxinological regions in Tropical America, based on venom composition and immunochemical criteria: LCA/Colombia/Amazonia (Region I), Venezuela (Region II), southeast South America (Region III), and a fourth region encompassing species related to toxinologically divergent Tityus cerroazul. Importantly, our molecular and cross-reactivity results highlight the need for new antivenoms against species inhabiting Region I, where scorpions may produce venoms that are not significantly reactive against available antivenoms UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)

In this study, we characterize the venom of Centruroides edwardsii, one of the most abundant scorpions in urban and rural areas of Costa Rica, in terms of its biochemical constituents and their biological activities. C. edwardsii venom is rich in peptides but also contains some higher molecular weight protein components. No phospholipase A2, hemolytic or fibrinogenolytic activities were found, but the presence of proteolytic and hyaluronidase enzymes was evidenced by zymography. Venom proteomic analysis indicates the presence of a hyaluronidase, several cysteine-rich secretory proteins, metalloproteinases and a peptidylglycine α-hydroxylating monooxygenase like-enzyme. It also includes peptides similar to the Kþ-channel blocker margatoxin, a dominant toxin in the venom of the related scorpion C. margaritatus. MS and N-terminal sequencing analysis also reveals the presence of Naþ-channel-modulating peptides with sequence similarity to orthologs present in other scorpion species of the genera Centruroides and Tityus. We purified the hyaluronidase (which co-eluted with an allergen 5-like CRiSP) and sequenced ~60% of this enzyme. We also sequenced some venom gland transcripts that include other cysteine-containing peptides and a Non-Disulfide Bridged Peptide (NDBP). Our in vivo experiments characterizing the effects on potential predators and prey show that C. edwardsii venom induces paralysis in several species of arthropods and geckos; crickets being the most sensitive and cockroaches and scorpions the most resistant organisms tested. Envenomation signs were also observed in mice, but no lethality was reached by intraperitoneal administration of this venom up to 120 μg/g body weight. Universidad de Costa Rica/[741-A5-048]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicina UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

La tenencia de herpetofauna en cautiverio es una actividad que ha experimentado un enorme desarrollo en distintas partes del mundo, constituyéndose en la base de muchos programas de conservación, educación, e investigación. En Costa Rica, esta tendencia se evidencia en la proliferación de centros que mantienen reptiles y anfibios en las últimas dos décadas. Pese a este desarrollo, no hay disponible información centralizada sobre los herpetarios a nivel del país, por lo que se desconoce la forma como operan o los potenciales impactos que pudieran tener en la conservación de las especies mantenidas en ellos. En este trabajo se describen los centros que actualmente funcionan en el país, para lo cual se realizaron entrevistas a sus propietarios o regentes y visitas de conformación. Un total de 33 centros, que en conjunto albergan 144 especies, fueron encontrados. Este número de herpetarios resulta del desarrollo de la industria turística: la mayoría de ellos tienen como finalidad la exhibición de animales, aunque también algunos reportan fines educativos. Solo en cuatro centros se encontró clara evidencia de programas de investigación, pese a que la mayoría de herpetarios indicó la generación de conocimiento como uno de sus principales objetivos. Una proporción importante de establecimientos obtiene sus animales del medio, lo que supone un impacto en aquellas especies con poblaciones reducidas. Tal parece ser el caso de la matabuey Lachesis stenophrys, que se encontró en 66% de los centros, pese a ser una especie con poblaciones amenazadas en el país actualmente. La existencia de estos establecimientos demuestra el interés de nuestra sociedad por la tenencia de vida silvestre, y supone un interesante mosaico de experiencias, posibilidades y retos para la escena ambiental del país. The maintenance of reptiles and amphibians in captivity has greatly developed worldwide, becoming the basis of many conservation, education, and research programs. In Costa Rica, this trend is evident in the proliferation of centers that maintain herpetofauna in the last two decades. Despite this development, there is no information available on the centers existing in Costa Rica, and the way they operate, or the potential impacts they could have on the species kept remain unknown. In this study, we describe the facilities currently operating in the country, through a series of interviews to their owners or technical staff, and in situ observations. A total of 33 centers were found, which keep up to 144 species of reptiles and amphibians. This large number of facilities resulted from the development of the tourism industry in the country: most of them are intended to display animals, although some reported educational purposes. Most interviewed staff claims that generation of knowledge is one of the main objectives of their center. However, only four of them showed clear evidence of research programs. A significant percentage of centers get their animals directly from the natural environment, a practice that might have an impact on species with reduced populations in the wild. This seems to be the case of the Bushmaster Lachesis stenophrys, found in 66% of the centers, despite being a species that is nowadays threatened in the country. The existence of these facilities demonstrates the interest Costa Rica society has on wildlife, and it is an interesting mosaic of experiences, opportunities, and challenges for the environmental scene of the country. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)

We evaluate adaptation of eleven species of wild-caught snakes maintained in captivity for venom production using two procedures for estimating survival rates. Kaplan-Meier estimations of survival time provide a better account of subsistence in captivity than estimations based solely on mean time to death. Highland and mid-elevation species are better adapted to our captive settings, but factors such as body condition at admission, locality of origin, seasonality, and maintenance protocol, affect the studied species differently. Periodic estimations of the collection's mortality rates, coupled with necropsy analyses, are recommended to assess adaptation and to develop acceptable species-specific management practices in captivity.

The ability to assess and avoid predation risk is thought to be a major determinant of behavior for small mammals. We assessed the antipredator responses of three Neotropical rodent species (Heteromys desmarestianus, Peromyscus mexicanus and Melanomys caliginosus) to cues (feces or actual presence) of the snake Bothrops asper. We investigated whether rodents avoided entering or spent less time in snake-cued areas using an experimental arena, and whether rodents reduced foraging efforts (measured by giving-up density) in snake-cued areas under laboratory, semi-natural and field conditions. P. mexicanus and M. caliginosus did not demonstrate any snake avoidance, and did not reduce foraging efforts under any conditions. H. desmarestianus significantly avoided live snakes only at very short distances (

2082/04 Embargo por política editorial The genus Bothriechis comprises a lineage of nine species of Neotropical pitvipers distributed mainly in highlands across Middle America, all adapted to arboreal habitats. Bothriechis supraciliaris is a relatively recently described species that inhabits the Pacific southwest of Costa Rica, whose venom had never been studied. A proteomic and toxicological profiling of its venom is here reported. Proteins or peptides that belong to eleven families were found, with a predominance of bradykinin-potentiating peptides (21.9%), followed by serine proteinases (15.2%) and phospholipases A2 (13.4%). A group of short polyglycine peptides, resembling the poly-His/poly-Gly metalloproteinase inhibitors described in Atheris and Echis snake venoms, was observed for the first time in a Bothriechis venom. Comparison of the venom proteome of B. supraciliaris with those of Bothriechis schlegelii, Bothriechis lateralis, and Bothriechis nigroviridis, confirms the highly diverse toxicological strategies evolved by these arboreal snakes in each case, as possible alternative solutions to the same trophic purpose. Toxicological profiling of B. supraciliaris venom revealed a potent hemorrhagic action, moderate myotoxicity, and very weak procoagulant activity. Importantly from the medical perspective, the lethal activity of its venom (mouse intraperitoneal LD50: 7.1 μg/g) was efficiently neutralized by a polyvalent (Viperidae) antivenom of therapeutic use in Central America. Ministerio de Ciencia y Tecnología/[108-2011]/MICITT/Costa Rica Consejo Nacional para Investigaciones Científicas y Tecnológicas/[108-2011]/CONICIT/Costa Rica Universidad de Costa Rica/[741-B1-549]/UCR/Costa Rica Ministerio de Innovación y Ciencia/[BFU2010-17373]//España Generalitat Valenciana/[PROMETEO/2010/005]//España Consejo Superior de Investigaciones Científicas/[2009CR0021]/CRUSA-CSIC/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)

The swamps dominated by raffia palm Raphia taedigera are conspicuous environments in the Tortuguero floodplains and in other wet regions along the Caribbean and Pacific coasts of Costa Rica. However, these environments have been little studied and are exposed to numerous threats, most importantly their replacement by agricultural activities or pastureland. In this paper, we describe some applications and uses of the raffia palms and other palms that are common in these flooded swamps. We also describe the efforts that have been made in Costa Rica for the protection or raffia-dominated swamps, through the environmental law frame of the country and the establishment of a protection system based on wilderness areas under different categories of protection. We discuss issues relevant to the future of these environments in the regions where they are distributed.

American Elapid snakes (Coral Snakes) comprise the genera Leptomicrurus , Micruroides and Micrurus, which form a vast taxonomic assembly of 330 species distributed from the South of United States to the southern region of South America. In order to obtain venom for animal immunizations aimed at antivenom production, Coral Snakes must be kept in captivity and submitted periodically to venom extraction procedures. Thus, to maintain a snake colony in good health for this purpose, a complete alternative diet utilizing an easily obtained prey animal is desirable. The development of a diet based on fish is compared to the wild diet based on colubrid snakes, and assessed in terms of gain in body weight rate (g/week), longevity (weeks), venom yield (mg/individual), venom median lethal dose (LD 50 ) and venom chromatographic profiles. The animals fed with the fish-based diet gained more weight, lived longer, and produced similar amount of venom whose biological and biochemical characteristics were similar to those of venom collected from specimens fed with the wild diet. This fish-based diet appears to be suitable (and preferable to the wild diet) to supply the nutritional requirements of a Micrurus nigrocinctus snake collection for the production of antivenom.

The general objective of this thesis is the numerical simulation of strong ground motions due to earthquakes. Significant deformations of the soil generate nonlinear behaviors in the superficial layers. The main contribution of this work is to take into account the nonlinearity of the media in a discontinuous Galerkin finite elements context. Different constitutive laws are implemented and analyzed. The particular case of theMasing-Prandtl-Ishlinskii-Iwan (MPII) elastoplastic model is looked at in-depth. This study is divided into two parts. A first one that aims at defining the framework of the problem by presenting the equations and models used to describe the soil motion. In this part we also present the Galerkin Discontinuous spatial approximation method as well as the different temporal schemes that we considered. Particular attention is paid to the algorithmic complexity of the nonlinear elastoplastic MPII model in order to reduce the computation time of simulations. The second part is dedicated to numerical applications. These applications are divided into three distinct categories. 1) We are first interested in the one-dimensional configuration where a single shear wave is propagated. In this context, an upwind numerical flux is established and applications to nonlinear elastic and nonlinear elastoplastic cases are studied. Ananalytical solution concerning the nonlinear elastic case is proposed, which makes it possible to carry out a numerical study of convergence. 2) The one-dimensional problem extended to the three components of the motion is studied and used as a first step towards 3D applications considering the coupling between the shear and compression waves. We are interested here in synthetic and real input signals. The application of a method that significantly reduces the calculation time of the elastoplastic model; L'objectif général de la thèse est la simulation numérique des mouvements forts du sol dûs aux séismes. Les déformations importantes du sol engendrent des comportements nonlinéaires dans les couches superficielles. L'apport principal de la thèse est la prise en compte de la nonlinéarité des milieux dans un contexte éléments finis Galerkin discontinus. Différentes lois de comportement sont implémentées et analysées. Le cas particulier du modèle élastoplastique de Masing-Prandtl-Ishlinskii-Iwan (MPII) est approfondi. Cette étude est divisée en deux parties. Une première qui vise à poser la structure du problème en présentant les équations et modèles utilisés pour décrire les mouvements du sol. Dans cette partie nous présentons également la méthode d’approximation spatiale Galerkin Discontinue ainsi que les différents schémas temporels que nous avons considérés. Une attention particulière est portée sur la complexité algorithmique du modèle nonlinéaire élastoplastique MPII en vue de réduire le temps de calcul des simulations. La deuxième partie est dédiée aux applications numériques. Ces applications sont réparties en trois catégories distinctes. 1) Nous nous intéressons toutd’abord à la configuration unidimensionnelle où une seule onde de cisaillement est propagée. Dans ce contexte, un flux numérique décentré est établi et des applications aux cas nonlinéaire élastique et nonlinéaire élastoplastique sont étudiées. Une solution analytique concernant le cas nonlinéaire élastique est proposée, ce qui permet de réaliser une étude numérique de convergence. 2) Le problème unidimensionnel étendu aux trois composantes du mouvement est étudié et utilisé comme un premier pas vers le 3D compte tenu du couplage entre les ondes de cisaillement et de compression. Nous nous intéressons ici à des signaux synthétiques et réels. L’application d’une méthode permettant de réduire significativement le temps de calcul du modèle élastoplastique est détaillée. 3) Une configuration tridimensionnelle est examinée. Après différentes applications de vérification en milieu linéaire, deux cas d’étude élastoplastique sont analysés. Une première sur un mode propre d’un cube puis une seconde sur un milieu plus réaliste composé d’un bassin hémisphérique à couches sédimentaires ayant un comportement élastoplastique

The general objective of this thesis is the numerical simulation of strong ground motions due to earthquakes. Significant deformations of the soil generate nonlinear behaviors in the superficial layers. The main contribution of this work is to take into account the nonlinearity of the media in a discontinuous Galerkin finite elements context. Different constitutive laws are implemented and analyzed. The particular case of theMasing-Prandtl-Ishlinskii-Iwan (MPII) elastoplastic model is looked at in-depth. This study is divided into two parts. A first one that aims at defining the framework of the problem by presenting the equations and models used to describe the soil motion. In this part we also present the Galerkin Discontinuous spatial approximation method as well as the different temporal schemes that we considered. Particular attention is paid to the algorithmic complexity of the nonlinear elastoplastic MPII model in order to reduce the computation time of simulations. The second part is dedicated to numerical applications. These applications are divided into three distinct categories. 1) We are first interested in the one-dimensional configuration where a single shear wave is propagated. In this context, an upwind numerical flux is established and applications to nonlinear elastic and nonlinear elastoplastic cases are studied. Ananalytical solution concerning the nonlinear elastic case is proposed, which makes it possible to carry out a numerical study of convergence. 2) The one-dimensional problem extended to the three components of the motion is studied and used as a first step towards 3D applications considering the coupling between the shear and compression waves. We are interested here in synthetic and real input signals. The application of a method that significantly reduces the calculation time of the elastoplastic model, L'objectif général de la thèse est la simulation numérique des mouvements forts du sol dûs aux séismes. Les déformations importantes du sol engendrent des comportements nonlinéaires dans les couches superficielles. L'apport principal de la thèse est la prise en compte de la nonlinéarité des milieux dans un contexte éléments finis Galerkin discontinus. Différentes lois de comportement sont implémentées et analysées. Le cas particulier du modèle élastoplastique de Masing-Prandtl-Ishlinskii-Iwan (MPII) est approfondi. Cette étude est divisée en deux parties. Une première qui vise à poser la structure du problème en présentant les équations et modèles utilisés pour décrire les mouvements du sol. Dans cette partie nous présentons également la méthode d’approximation spatiale Galerkin Discontinue ainsi que les différents schémas temporels que nous avons considérés. Une attention particulière est portée sur la complexité algorithmique du modèle nonlinéaire élastoplastique MPII en vue de réduire le temps de calcul des simulations. La deuxième partie est dédiée aux applications numériques. Ces applications sont réparties en trois catégories distinctes. 1) Nous nous intéressons toutd’abord à la configuration unidimensionnelle où une seule onde de cisaillement est propagée. Dans ce contexte, un flux numérique décentré est établi et des applications aux cas nonlinéaire élastique et nonlinéaire élastoplastique sont étudiées. Une solution analytique concernant le cas nonlinéaire élastique est proposée, ce qui permet de réaliser une étude numérique de convergence. 2) Le problème unidimensionnel étendu aux trois composantes du mouvement est étudié et utilisé comme un premier pas vers le 3D compte tenu du couplage entre les ondes de cisaillement et de compression. Nous nous intéressons ici à des signaux synthétiques et réels. L’application d’une méthode permettant de réduire significativement le temps de calcul du modèle élastoplastique est détaillée. 3) Une configuration tridimensionnelle est examinée. Après différentes applications de vérification en milieu linéaire, deux cas d’étude élastoplastique sont analysés. Une première sur un mode propre d’un cube puis une seconde sur un milieu plus réaliste composé d’un bassin hémisphérique à couches sédimentaires ayant un comportement élastoplastique

The difficulty of dealing with complex geotechnical projects implies the necessity to determine adequately soil’s behaviour with strain’s increase. The information provided for these geotechnical studies mostly concerns soil’s in situ resistance and it is only punctual. In order to fully characterize soil’s behaviour with strains, this work exposes a detailed study of the shear modulus evolution with increasing strain by using surface waves methods, geotechnical laboratory tests such as soil mechanics tests and geotechnical in situ tests such as pressure meter test. More sophisticated tests such as resonant column test and cyclic triaxial test have been also used for this purpose. The experimental program described soil behaviour as being nonlinear. This observed behaviour permitted to propose an approach of characterizing the behaviour of soil incase if the needed information is only partial. This thesis manuscript presents a data synthesis of different types of in situ and laboratory tests which allowed describing soil shear modulus evolution for different ranges of deformation; Les projets géotechniques deviennent de plus en plus complexes et il s’avère alors nécessaire de caractériser de manière complète le comportement du sol dans les différentes plages de déformations sollicitées par le projet. Cependant les moyens mis en place lors de ces études sont souvent limités à quelques essais ponctuels lesquels ne donnent pour la plupart qu’une information liée à la résistance du terrain. Afin de caractériser de manière complète le comportement du sol avec la déformation, ce travail expose une étude détaillée de l’évolution du module de cisaillement avec la déformation en utilisant les méthodes d’ondes de surface, les essais géotechniques de laboratoire de mécanique des sols et les essais géotechniques in situ au pressiomètre. Des essais plus sophistiqués tels que l’essai à la colonne résonnante étau triaxial cyclique ont été aussi utilisés dans ce cadre. Le programme expérimental a permis de déterminer que le comportement du sol est non linéaire avec la déformation. Les observations réalisées ont permis de pouvoir proposer une démarche de caractérisation du comportement du sol en cas de disposition d’une information partielle. Ce mémoire de thèse présente une synthèse des données collectées par différents types d’essais in situ et en laboratoire qui ont permis de décrire l’évolution du module de cisaillement dans les différentes plages de déformations

Numerical modeling of seismic wave propagation has been a major topic on ground motion studies using a number of different numerical integration schemes. The consideration of soil nonlinearity holds an important place in order to achieve simulations consistent with real observations for strong seismic shaking. Additionally, in the presence of strong ground motion in saturated soils, pore pressure becomes an important parameter to take into account for related phenomena such as flow liquefaction and cyclic mobility. In this study, first, one component (1C) - seismic wave propagation is modeled in linear and nonlinear media in 1D based on the spectral element numerical method. Viscoelastic and nonlinear soil rheologies are implemented by use of the memory variables technique and Iwan’s elastoplastic model, respectively. Then, the same study is extended to a 1D - three component (3C) model and a preliminary comparison on the effect of using 1C and 3C approaches is made. Then, the influence of excess pore pressure development is included in the 1D-3C model and the developped numerical model is applied to realistic case on the site of Wildlife Refuge Liquefaction Array (USA) which is affected by the 1987 Superstition Hills event. The ground motion modification for different assumptions of the soil rheology in the media and different input motions is studied. The calculated motion is found to be amplified on low frequency and damped in high frequency range due to excess pore pressure development. Furthermore, the soil is found to be more nonlinear under triaxial loading in 3C approach and more dilative due to higher nonlinearity. Despite the similitude in surface acceleration and velocity results, significant differences in surface displacement results of 1C and 3C approaches are remarked. Similar analyses are performed on two Japanese sites Kushiro Port and Onahama Port, which are influenced by the 1993 Kushiro-Oki and the 2011 off the Pacific coast of Tohoku earthquakes, respectively. It has been shown that the nonlinearity-related changes are not homogeneous all over the concerned frequency band and the influence of cohesionless soil behavior on wave propagation is highly dependent on model properties and loadingconditions. Lastly, the 2D SEM code is developped by taking into account soil nonlinearity and pore pressure effects similary to 1D-3C SEM code. The developped 2D SEM code is applied to a 2D sedimentary basin site where the basin geometry is asymmetrical and soil profile consists of layers with different nonlinearity properties. Total and effective stress analyses are performed on the 2D basin for P-SV and SH zave propagation models. The calculated surface motion is shown to differ significantly under synthetic and realistic input motion loading conditions and the resultant deformation in superficial layers is found to be very high in effective stress analysis compared to total stress analysis. Also, wave propagation takes longer time inside basin media and the reflections on bedrock-basin boundaries lead the soil in basin edges to higher nonlinearity. This study shows the possibility of modeling nonlinear soil behavior including pore pressure effects in seismic wave propagation studies by coupling different models with spectral element method. These analyses help identifying and understanding dominant phenomena occurring in superficial layers, depending on local conditions and input motions. This is of great importance for site-specific studies, La modélisation numérique de la propagation des ondes sismiques fait partie des études principales sur le calcul du mouvement sismique basées sur de différents schèmes numériques. La prise en compte du comportement nonlinéaire du sol est consideré désormais très important afin de pouvoir calculer la réponse du milieu cohéremment aux observations sous les sollications sismiques très fortes. En plus, le paramètre de pression interstitielle, qui pourrait emmener le sol aux phénomènes de liquéfaction, devient très important pour les sols saturés. Dans cette étude, dans un premier temps, la propagation des ondes sismiques est modelisée sur une composante (1C) dans les milieux linéaires et nonlinéaires en utilisant la méthode numérique des éléments spéctraux. Les rhéologies viscoélastique et nonlinéaire sont implementées par le méthode de technique des variables de mémoire et le modèle élastoplastique d’Iwan, respectivement. Ensuite, le modèle 1D - trois composantes (3C) est développé et une comparaison préalable sur l’effet de la considération des approches 1C et 3C est faite. L’effet de pression interstitielle est implementé dans le code 1D-3C et le site américain Wildlife Refuge Liquefaction Array (WRLA), qui a été frappé par le séisme de Superstition Hills en 1987 est étudié. Le changement de la réponse du sol sous les différents hypothèses de rhéologie du sol et de mouvement d’entrée est étudié. Le mouvement calculé est noté d’être amplifié pour les basses fréquences et atténué pour les hautes fréquences en raison de l’excès de pression interstitielle dans les sols liquéfiables. Par ailleurs, le sol devient plus nonlinéaire sous le chargement triaxial dans l’approche 3C et plus dilatant dû à la nonlinéarite élevée. En dépit de la similitude entre les accélérations et les vitesses en surface des approches 1C et 3C, une importante différence dans le déplacement en surface entre les deux approches est notée. Les analyses sont répétées pour deux sites japonais Kushiro Port et Onahama Port, qui ont été influencés par le séisme de Kushiro-Oki en 1993 et le séisme de la côte Pacifique de Tohoku en 2011, respectivement. Il a été montré que les changements apportés par la nonlinéarite ne sont pas identiques dans toute la gamme de fréquence concernée et l’influence du comportement des sols non-cohésives sur la propagation des ondes sismiques dépend fortement des propriétés du modèle et des conditions de chargement. Dernièrement, le code SEM est avancé en 2D en considerant les mêmes modèles implementés en 1D-3C pour la nonlinéarite du sol et les effets de pression interstitielle. Le code SEM 2D est mis en application dans un modèle de bassin sédimentaire dont la géometrie est assymmétrique et le profile du sol est composé des couches possédant différentes propriétés nonlinéaires. Le modèle est étudié par les analyses totale et effective pour les propagation des ondes P-SV et SH. La differentiation du mouvement calculé en surface est très importante sous les chargements avec les signaux d’entrée synthétique et réel. L’analyse effective résulte en plus de déformations dans les couches superficielles par rapport à l’analyse totale.De plus, la durée de propagation des ondes augmente à l’intérieur du bassin et les reflections aux frontières de bassin-rocher entraînent plus de nonlinéarite dans les coins du bassin. Cette thèse révèle la possibilité de la modélisation du comportement nonlinéaire du sol en prenant en compte l’effet de pression interstitielle dans les études de la propagation des ondes sismiques en couplant les modèles différents avec la méthode des éléments spéctreaux. Ces analyses contribuent à l’identification et la compréhension des phénomènes majeures qui se déroulent dans les couches superficielles en respectant les conditions locales et les mouvements d’entrées, ce quirend ce travail très important pour les études spécifiques de sites