reproductive isolation

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Coevolution of male and female mate choice can destabilize reproductive isolation

Coevolution of male and female mate choice can destabilize reproductive isolation

ferent color pattern loci 50 . Therefore, choosy individuals may not completely stop courting/mating across ecotype boundaries because each sex relies on different aspects of the phenotype. Our model predicts that this error-proneness could strengthen selec- tion favoring mutual mate choice, which could in turn inhibit preference cycling and stabilize reproductive isolation. Thus, perhaps counterintuitively, our model suggests that imperfect male preferences lead to strong reproductive isolation in the long- term by maintaining selection favoring female preferences, and preventing drift-induced preference cycling. Such counter- intuitive results are not unheard of: in the context of local adaptation, imperfect female choice has been shown to be more strongly favored by selection than perfect choice because it Number of consecutive time steps in regime
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Dissecting functional components of reproductive isolation among closely related sympatric species of the Anopheles gambiae complex

Dissecting functional components of reproductive isolation among closely related sympatric species of the Anopheles gambiae complex

1 | INTRODUCTION Speciation proceeds by the progressive establishment of reproductive isolation among genetically distinct populations. Reproductive iso- lation results from the combined effect of all barriers to gene flow, which can be conveniently classified into three functional components (Mallet, 2006): (i) natural selection against immigrants from alternative ecological niches; (ii) sexual isolation due to assortative mating or fer- tilization; and (iii) selection against zygotes formed when hybridization does occur. The latter mechanism can be further partitioned according to whether selection results from the presence of intrinsic genetic in- compatibilities, expressed in the form of hybrid sterility or inviability independent of the environment, or rather from inferior hybrid geno- types as a result of ecological mechanisms, a process also known as extrinsic postmating isolation. Barriers to gene flow are therefore mul- tifarious, with the accumulation of multiple mechanisms in the course of population divergence gradually producing an increase in the nature and strength of isolation. Accordingly, time since lineage divergence is a reasonable predictor of the strength of reproductive isolation, as closely related taxa exhibit weaker isolation compared to distantly re- lated ones (Coyne & Orr, 1998; Orr & Coyne, 1989). While this rela- tionship holds true noisily, several evolutionary processes can distort it when considering closely related taxa issuing from recent adaptive radiations: at this phylogenetic level, the strength of reproductive iso- lation can be modulated by geographical, historical or ecological fac- tors that weaken or strengthen the barriers against gene flow.
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Differentiation in putative male sex pheromone components across and within populations of the African butterfly Bicyclus anynana as a potential driver of reproductive isolation

Differentiation in putative male sex pheromone components across and within populations of the African butterfly Bicyclus anynana as a potential driver of reproductive isolation

components per Bicyclus species, and ~20% of the younger pairs of Bicyclus species displayed one to three pMSP differences, while all pairs of Bicyclus species dif- fered on average by seven pMSP compounds (Bacquet et al. 2015). Thus, the qualitative differences observed between populations in this study were of the same mag- nitude as those observed among closely related species and that participate to reproductive isolation across the genus (Bacquet et al. 2015). Moreover, such chemical dif- ferences are of greater magnitude than those found in female sex pheromones in moths (Linn and Roelofs 1989). Overall, neutral genetic divergence between pairs of B. anynana populations was lower than variation in pMSP although the small sample size for the chemical data could inflate Φ ST values. In addition, a similar level of chemical differentiation was also found within the genetically undifferentiated population of B. anynana in Kenya (Figs. 1, 4). Furthermore, there is evidence of ongoing gene flow between all B. anynana populations as they share a similar mitochondrial haplotype, and we found three individuals in Uganda that appear to be crosses between the two subspecies. The greater chemical than genetic differentiation lends support to the hypothe- sis that chemical divergence was concomitant, or pre- ceded, genetic divergence.
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The contribution of ancient admixture to reproductive isolation between European sea bass lineages

The contribution of ancient admixture to reproductive isolation between European sea bass lineages

that RI barriers can evolve via reticulate gene flow across multiple species boundaries. Speciation is the evolutionary process that leads to the emergence of new species through the progressive establish- ment of reproductive isolation (RI) barriers among diverging populations (Coyne and Orr 2004). Identifying those barriers and understanding the eco-evolutionary context in which they evolved has been at the core of the speciation genetics research program (Presgraves 2010; Wolf et al. 2010). Over the last decade, progress in sequencing technologies has allowed im- portant insights into the genetic basis of RI barriers through the study of genome-wide differentiation/divergence patterns among closely related species (Feder et al. 2012; Seehausen et al. 2014; Harrison and Larson 2016; Wolf and Ellegren 2016; Ravinet et al. 2017). An important result of speciation genomics studies is that the age of the alleles located within genomic regions involved in RI is often much older than the average coalescent time computed across the whole genome. This finding indicates that the regions involved in RI tend to be enriched for anciently diverged haplotypes. An example of this comes from the fixed chromosomal inversions involved in RI between Drosophila
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Low and asymmetrical gene flow in the cordonnier: geographic barrier or reproductive isolation ?

Low and asymmetrical gene flow in the cordonnier: geographic barrier or reproductive isolation ?

imA analysis, nuclear DNA (above); mtDNA (below). Reconstructed gene flow between Mozambique Chan- nel (MZC) and Mascarenes (MAS) was bidirectional for nuclear markers but unidirectional for the mito- chondrial marker. Although weak, gene flow predomi- nantly occurred from MZC to MAS, opposite to the main westward oceanographic circulation. A conti- nent-island model where Ne(MZC) >> Ne(MAS) explains this result. Asymmetric gene flow of mtDNA relative to nDNA is common in situations of second- ary contact with incomplete reproductive isolation.

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Geographically distinct patterns of reproductive isolation and hybridisation in two sympatric species of the Jaera albifrons complex (marine isopods)

Geographically distinct patterns of reproductive isolation and hybridisation in two sympatric species of the Jaera albifrons complex (marine isopods)

hierarchical  analyses  of  variance  without  the  individuals  showing  an  intermediate  phenotype  (see  main   text).     Figure  S6:  Patterns  of  isolation-­‐by  distance  observed  in  Brittany  for  Jaera  albifrons  (blue  circles;  y=0.0209x   +0.0011,  R 2   =  0.73,  Mantel  test  p-­‐value  <  0.01)  and  J.  praehirsuta  (green  circles;  y=0.0065x  -­‐0.0133,  R²=0.11,   Mantel  test  p-­‐value  =  0.02).    
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Multi-level Isolation for Android Applications

Multi-level Isolation for Android Applications

A second important part of our architecture is implemented as a bare metal hypervisor controlling the execution of the Linux kernel. Only a few functionalities are implemented in this hypervisor to keep its footprint as light as possible: It ensures the integrity of other parts of our solution, as well as critical components in the Linux kernel; and it checks the syscall sources to prevent any attempt to bypass the provided isolation. Indeed, an application may emit syscalls by their own without using our modified libc.

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Isolation réseau dans un environnement Cloud Public/Hybride

Isolation réseau dans un environnement Cloud Public/Hybride

Nous avons ensuite divisé les protocoles en nous basant sur leur méthode d’isolation. Nous avons distingué deux méthodes d’isolation pour isoler les utilisateurs et leur trafic. Ces méthodes sont : Host isolation et Core isolation. La première méthode appelée Host isolation, ou Isolation au niveau de l’hôte en fran- çais, sélectionne et applique l’isolation des flux lorsque ceux-ci arrivent à l’hôte de des- tination. Ceci signifie qu’aucun équipement sur le chemin d’un flux ne va vérifier si sa destination l’accepte ou non. Ces équipements ne se préoccupent que de faire transiter ou router les paquets du flux afin d’atteindre la destination. Ce n’est seulement qu’une fois le paquet arrivé à destination que la machine destination vérifie si elle peut ou non accepter le paquet. Il en résulte que l’isolation des trafics utilisateurs ne se fait pas grâce aux équipements intermédiaires (middleboxes) du réseau, mais grâce aux machines hôte. Ces dernières acceptent ou rejettent les paquets en fonction de l’isolation à appliquer en vérifiant si la VM destination appartient ou non au même utilisateur que la VM source. Cette méthode d’isolation permet de conserver des équipements réseau (les middleboxes) simples, car ils n’ont pas à connaître la topologie complète du réseau. En effet, comme ils ne font pas respecter l’isolation des flux, ils n’ont pas à savoir si la source et la des- tination d’un paquet appartiennent bien au même utilisateur. Cependant, cette méthode d’isolation possède deux désavantages qui sont :
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Isolation of plant cell wall proteins

Isolation of plant cell wall proteins

Since labile proteins can be lost during the preparation of cell walls, they must be extracted from tissues by non-destructive techniques such as vacuum infiltration (9), or recovered [r]

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"Où est mon andrologue ?" : le tabou masculin en santé sexuelle et reproductive

"Où est mon andrologue ?" : le tabou masculin en santé sexuelle et reproductive

L’étude de l’histoire des différentes pratiques médicales liées à la santé sexuelle  et reproductive permet de faire le constat d’une profonde interpénétration entre  représentations sociales et représentations médicales. La pertinence des objets  de  recherches,  les  prénotions  avec  lesquelles  ils  sont  abordés,  ainsi  que  la  réception  des  énoncés  scientifiques  produits  sont  déterminées  socialement,  en  fonction  des  représentations  et  des  demandes  de  la  société  vis‐à‐vis  du  corps  scientifique.  Les  travaux  de  critique  féministe  des  sciences,  ainsi  que  l’étude  historique  et  sociologique  de  la  production  de  connaissances  scientifiques,  ont  montré l’incidence de conceptions sexuées du monde sur la compréhension des  faits  observés,  le  vocabulaire  employé  ou  encore  les  impensés  des  recherches  scientifiques.  Les  relations  constantes  unissant  société  et  monde  scientifique  délimitent  le  champ  des  possibles  et  rendent  l’émergence  d’alternatives  marginales  difficile :  les  changements  de  conceptions  en  science  ne  peuvent  surgir  qu’à  la  faveur  d’évolutions  sociopolitiques  modifiant  la  pertinence  des  énoncés.  Le  contrôle  de  pertinence  s’effectue  notamment  à  travers  les  réseaux  d’acteurs  impliqués  dans  le  développement  de  nouvelles  connaissances,  technologies et pratiques car la reconnaissance entre pairs est déterminante du  destin  des  hypothèses.  L’importance  des  interactions  entre  acteurs  est  accrue  dans le domaine médical, car le corps des médecins se définit par la distinction  sociale  impliquée  par  son  accès  restreint.  Appartenir  au  corps  médical  sous‐ entend l’acceptation des règles de fonctionnement de ce monde, règles qui sont  transmises  au  cours  d’un  enseignement  long  et  organisé  hiérarchiquement,  et  l’engagement dans une voie marginale met en péril la carrière des acteurs. 
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Challenges of microsatellite isolation in fungi

Challenges of microsatellite isolation in fungi

Dalleau-Clouet, C., Gauthier, N., Risterucci, A.M., Bon, M.C., Fargues, J., 2005. Isolation and characterization of microsatellite loci from the entomopathogenic hyphomycete, Paecilomyces fumosoroseus. Mol. Ecol. Notes 5, 496-498. Della Rosa, V., Cappuccio, I., Fanelli, C., Urbanelli, S., 2004. Isolation and characterization of microsatellite markers in two basidiomycete species: Pleurotus eryngii and P. ferulae. Mol. Ecol. Notes 4, 271-273.

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Isolation thermique haute performance : toujours plus

Isolation thermique haute performance : toujours plus

Les panneaux d’isolation sous vide (PIV) sont des éléments dont la performance est basée sur le fait que l’absence ou la réduction de la pression gazeuse à l’intérieur du matériau à por[r]

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Bernstein's basis and real root isolation

Bernstein's basis and real root isolation

the coefficients of Q, since every node in the tree created by Algorithm 3.4 (Real Root Isolation) is visited at most three times in Algorithm 3.6 (Improved Real Root Isolation). However Algorithm 3.6 (Improved Real Root Isolation) uses only an O(p 3 (τ + log 2 (p))) workspace, since only one vector of Bernstein’s coefficients is stored throughout the computation in Algorithm 3.6 (Improved Real Root Isolation), rather than possible 2v in the Algorithm 3.4 (Real Root Isolation).

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Review of Active Vibration Isolation Strategies

Review of Active Vibration Isolation Strategies

g is used to remove the drifts of the payload. It can be realized with a Magneto-Rheological (MR) fluid [13-15] or MR elastomer [16,17]. A position feedback creates a so called sky-hook spring, because the actuator delivers the same force as a spring linking the mass to an imaginary point fixed in the sky. It relaxes the second tradeoff by creating both an isolation at low frequency (dashed curve in Fig. (2b)), and a stiffening of the isolator which improves the robustness to external disturbances (see Eq.(6)). Most of the active isolation strategies are based on a combination of a sky-hook spring and a sky-hook damper. Three different configurations are studied in details in the next section.
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Increase in Male Reproductive Success and Female Reproductive Investment in Invasive Populations of the Harlequin Ladybird Harmonia axyridis

Increase in Male Reproductive Success and Female Reproductive Investment in Invasive Populations of the Harlequin Ladybird Harmonia axyridis

1 Inra, Centre de Biologie pour la Gestion des Populations, Montpellier, France, 2 Inra, botAnique et bioinforMatique de l’Architecture des Plantes, Montpellier, France, 3 Laboratory of Forest Ecology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan Abstract Reproductive strategy affects population dynamics and genetic parameters that can, in turn, affect evolutionary processes during the course of biological invasion. Life-history traits associated with reproductive strategy are therefore potentially good candidates for rapid evolutionary shifts during invasions. In a series of mating trials, we examined mixed groups of four males from invasive and native populations of the harlequin ladybird Harmonia axyridis mating freely during 48 hours with one female of either type. We recorded the identity of the first male to copulate and after the 48 h-period, we examined female fecundity and share of paternity, using molecular markers. We found that invasive populations have a different profile of male and female reproductive output. Males from invasive populations are more likely to mate first and gain a higher proportion of offspring with both invasive and native females. Females from invasive populations reproduce sooner, lay more eggs, and have offspring sired by a larger number of fathers than females from native populations. We found no evidence of direct inbreeding avoidance behaviour in both invasive and native females. This study highlights the importance of investigating evolutionary changes in reproductive strategy and associated traits during biological invasions. Citation: Laugier GJM, Le Mogue´dec G, Tayeh A, Loiseau A, Osawa N, et al. (2013) Increase in Male Reproductive Success and Female Reproductive Investment in Invasive Populations of the Harlequin Ladybird Harmonia axyridis. PLoS ONE 8(10): e77083. doi:10.1371/journal.pone.0077083
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Highly infectious diseases in the Mediterranean Sea area: Inventory of isolation capabilities and recommendations for appropriate isolation

Highly infectious diseases in the Mediterranean Sea area: Inventory of isolation capabilities and recommendations for appropriate isolation

outbreak in West Africa, the spread of highly pathogenic avian influenza A and the emergence of new coronaviruses such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Some cases of imported or autochthonous viral haemorrhagic fever occurred in Europe, highlighting the need to improve preparedness for these dis- eases [5] . In particular, these diseases cannot be cared for in regular healthcare settings because their epidemic potential may pose a risk to healthcare workers (HCWs) and other patients. Patients with suspected or proven HIDs should be cared for in a high-level isolation unit (HLIU), a facility providing safe, secure, high-quality and appropriate care with optimal infection containment, prevention and control pro- cedures. The need for these isolation facilities was confirmed during the Ebola outbreak of 2013 –2015, during which many patients were treated in highly specialized centres in Western countries, with no case of secondary transmission. In contrast, when patients with Ebola were hospitalized in non–specially equipped hospitals, cases of transmission to HCWs occurred, mainly in African countries but also in Western countries [6] .
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SecureJS Compiler: Portable Memory Isolation in JavaScript

SecureJS Compiler: Portable Memory Isolation in JavaScript

We have implemented a secure JavaScript-to-JavaScript compiler, SecureJS. It transforms programs into equivalent ones, but which would execute as if they were running inside an isolated memory. The compilation relies on the translation to JS explicit and replaces primitive operations to secure versions and thus execute in an iso- lated memory, which simulates a JavaScript realm. The program running in the isolated memory can interact with others by inten- tionally exporting a value of the isolated memory to outside. This compiler is portable and only uses standard features so it can be used by any JavaScript engine that complies with ECMAScript 5.1 specification. Thus, the compiler provides an isolation mechanism independently of JavaScript implementation, and it enables us to use existing secure interaction libraries in any JavaScript engine.
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Hybrid Isolation Forest - Application to Intrusion Detection

Hybrid Isolation Forest - Application to Intrusion Detection

corresponds to the total number of anomalies observed for the given application layer. For IF, HIF1 and HIF2, the forests comprise 1024 trees and each tree is associated to a data sample containing 512 instances. For HIF and SVM approaches, the meta parameters have been selected such as maximizing the AUC values. The obtained AUC values are in general relatively high, except for the HTTPImage transfer application layer for which the AUC values for IF, HIF1 and HIF2 are respectively .55, .56 and .60. For this application layer, the detection of anomalies are much difficult because the attacks are deeply encoded into the image data packets that are transferred. The features we are using to represent the network data flows are not sufficiently discriminant to detect such anomalies. We note that the two baselines perform slightly better than the isolation forest based algorithms since 1C-SVM and 2C-SVM get respectively .64 and .69 AUC values for this application layer.
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Isolation des ADNc de l'antigène tumoral CA125 dans le cancer ovarien

Isolation des ADNc de l'antigène tumoral CA125 dans le cancer ovarien

Ce manque d'information est relié au fait que la purification totale de la protéine CA 125 est complexe, que son gène a été partiellement cloné seulement en 2001 et que sa séquence gén[r]

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Raisonnement sur les modèles : détection et isolation d'anomalies dans les systèmes de diagnostic

Raisonnement sur les modèles : détection et isolation d'anomalies dans les systèmes de diagnostic

As presented in the introductory chapter, the main objective of this dissertation is to provide Artificial Intelligence and Airbus with means for reasoning about abnormalities in Models [r]

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