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In this paper, we present some thoughts about the recent developments, made possible by technological advances and miniaturisation of connected visual prostheses, linked to the visual system, operating at different level of this one, on the retina as well as in the visual cortex. While these objects represent a great hope for people with impaired vision to recover partial vision, we show how this technology could also act on the functional vision of well sighted persons to improve or increase their visual performance. In addition to the impact on our cognitive and attentional mechanisms, such an operation when it originates outside the natural real visual field (e.g. cybernetics) raises a number of questions about the development and use of such implants or prostheses in the future.

Over a century after the first description of a polymorphism controlled by a supergene, these genetic architectures still puzzle biologists. Supergenes are groups of tightly linked loci facilitating the co-segregation of combinations of alleles underlying alternative, complex adaptive strategies. The suppression of recombination at supergenes is generally caused by polymorphic chromosomal rearrangements, such as inversions. The existence of inversion polymorphisms and supergene raises theoretical and empirical questions. Why do these architectures evolve? How can alternative combinations of alleles be formed? How and why is polymorphism maintained? The purpose of this paper is to provide answers to these questions by reviewing recent advances in the study of Heliconius numata, an Amazonian butterfly displaying a striking diversity of wing color patterns. In a broad context, this review highlights mechanisms that play an important role in the evolution of new genomic architecture and in the adaptation of species.

Most bacterial ribonucleases (RNases) known to date have been identified in either Escherichia coli or Bacillus subtilis. These two organisms lie on opposite poles of the phylogenetic spectrum, separated by 1-3 billion years of evolution. As a result, the RNA maturation and degradation machineries of these two organisms have little overlap, with each having a distinct set of RNases in addition to a core set of enzymes that is highly conserved across the bacterial spectrum. In this paper, we describe what the functions performed by major RNases in these two bacteria, and how the evolutionary space between them can be described by two opposing gradients of enzymes that fade out and fade in, respectively, as one walks across the phylogenetic tree from E. coli to B. subtilis.

Metastatic progression, which begins with the invasion and migration of tumor cells from a primary tumor, marks a major turning point in the evolution of cancer. Indeed, it eventually leads to the formation of secondary tumors, the metastases, which are very often responsible for the patient's death. Understanding the mechanisms controlling the different steps of this process, as well as those explaining the fundamental phenomenon of organotropism (i.e. the distribution of metastases in distant organs by a non-random and tumor-specific process), is essential to define new innovative therapeutic solutions. In this review paper, we will present how biomechanics is an essential element to this understanding, and will emphasize the importance of this orthogonal and promising angle of study as well as our laboratory's focus on the late stages of dissemination, arrest and extravasation of circulating cancer cells and factors secreted by the primary tumor such as extracellular vesicles.

As part of an ongoing survey of scorpion diversity in Colima, Mexico, the isolated mountain Cerro Grande, part of the Biosphere Reserve Sierra de Manantlán, was investigated. Centruroides possanii sp. nov., the fifth species of the genus from the state, was discovered during fieldwork in the massif and is described in the present paper. Physiographical and climatic features of Cerro Grande may restrict the range of this new species; thus, we hypothesized that it may be a microendemic species that requires priority conservation. The new species is not assigned to any Centruroides species group recognized because some of its morphological features do not fit the current diagnosis of any of these groups, and these different groups are non-monophyletic and consequently ill-diagnosed. The new species is profusely illustrated, particularly the hemispermatophore. A distribution map is presented along with the other two more common species distributed in Colima. Because only indirect data on the potency of its venom is available, the medical importance of this new species described here is yet to be known., (Copyright © 2019 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

Although scorpions have been described from China since the 19th century, it was only in the early 2000s that this fauna has seen a noticeable improvement in terms of the number and diversity of the described taxa. Some regions of China have been extensively prospected, while others remain largely unexplored. The latter is the case for the Province of Xinjiang, in the Extreme West of the country. A few contributions dealing with scorpions from this region are available, but these mainly concern representatives of the family Buthidae. In the present paper, a new species belonging to the genus Scorpiops Peters, of the family Scorpiopidae Kraepelin, is described from the Taxkorgan Natural Reserve. The description is based on one male and one female collected under stones at altitudes of 4500-4600m. To our knowledge, this is the first species ever described from the Taxkorgan Natural Reserve and may represent an endemic element within the fauna of Xinjiang Province., (Copyright © 2018 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

Morphological markers as well as two types of molecular markers, inter-sample sequence repeat (ISSR) and start codon targeted (SCoT) are suitable for species identification of the polygonati rhizoma germplasms. In this paper, we adopted these methods for the identification of rhizomes collected from 47 areas in China. Based on their morphological characters, the collected germplasms were classified into two populations, one with alternate leaf arrangement and the other with verticillate leaf arrangement, and they were comprised of five species and fourteen subgroups. Of the five species identified: Polygonatum kingianum, P. cirrhifolium, P. alternicirrhosum, and P. sibiricum belonged to one cluster, and P. cyrtonema belonged to a different cluster. According to the analysis of both ISSR and SCoT markers, all germplasms with greater genetic similarity were classified into one group. Especially, P. sibiricum and P. cirrhifolium, which shared ∼80% similarity, were clustered together, whereas the germplasms identified as P. kingianum with ∼86% similarity formed a separate clade. P. kingianum showed a much greater genetic similarity with P. cyrtonema than with P. sibiricum. The multidimensional scaling analysis further verified the accuracy and reliability of the molecular marker-based results. Thus, both morphological and molecular methods should be combined for the differentiation of germplasms such as those of polygonati rhizoma., (Copyright © 2018 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

Discocyrtanus canjinjim sp. n., belonging to the family Gonyleptidae Sundevall, 1833 is described based on nineteen specimens, eleven adult males and eight adult females, collected in the Vila Bela da Santíssima Trindade, in the State of Mato Grosso, Brazil. This new species represents an endemic component for the harvestmen fauna of Chiquitano Dry Forests terrestrial eco-region, being the most occidental point of distribution of the genus, notably found in the Cerrado and the Atlantic Forest. The new species is characterized by femur IV swollen with the same length of dorsal scutum, trochanter IV with prodorsal distal apophysis as a stout hook not bifurcated, and a unique form of genitalia in the genus. This paper also includes the first identification key to the species of the genus after its revalidation., (Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

Endocrine disruption is commonly thought to be restricted to a direct endocrine mode of action i.e. the perturbation of the activation of a given type of hormonal receptor by its natural ligand. Consistent with the WHO definition of an endocrine disrupter, a key issue is the "altered function(s) of the endocrine system". Such altered functions can result from different chemical interactions, beyond agonistic or antagonistic effect at a given receptor. Based on neuroendocrine disruption by polychlorinated biphenyls and bisphenol A, this paper proposes different mechanistic paradigms that can result in adverse health effects. They are a consequence of altered endocrine function(s) secondary to chemical interaction with different steps in the physiological regulatory processes, thus accounting for a possibly indirect endocrine mode of action., (Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

VIP and its receptors (VPACRs) are largely investigated in vertebrate testis, as well as their functions in the control of spermatogenesis and steroidogenesis. By contrast, a few data are available about the presence and role of VIP in the epididymis. The aim of the present paper was to investigate the localization of VIP and its receptors in the epididymis of two vertebrates: Podarcis sicula, a seasonal reproducer, and Rattus rattus, a continuous reproducer. By immunohystochemical investigation, we demonstrated for the first time that VIP and its receptors are widely represented in the epididymis of Podarcis sand Rattus; in particular in Podarcis, we showed that during the reproductive period, as well as in Rattus, VIP and its receptors are well represented in all the epithelial cells and the connective tissue of the epididymis; by contrast, during the non-reproductive period, VIP and its receptors are represented only in the connective tissue. The possible role of the VIP/VPACR system in the control of reproduction is discussed., (Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

Three plant oils (Cymbopogon citratus, Cymbopogon martini, and Pelargonium graveolens) were developed as EC formulations and tested for their physical stabilities. EC formulations (10EC, 20EC and 30EC) of C. citratus, C. martini and P. graveolens had emulsion stability, spontaneity property, heat and cold stability. EC formulated plant oils were screened against the major seed borne fungi of rice such as Curvularia lunata, Fusarium moniliforme, Bipolaris oryzae, and Sarocladium oryzae. The level of inhibition varied among the concentrations of EC formulations. Among the three EC formulations, that of C. citratus oil 30EC recorded 100% inhibition on the mycelial growth of test pathogens. In the blotter paper method, rice seeds treated with a formulation of C. citratus oil 30EC controlled the infection of C. lunata, F. moniliforme, B. oryzae and S. oryzae in rice seed to the tune of 66.0%, 60.4%, 66.0% and 69.1%, respectively. Seed soaking with formulation of C. citratus oil 30EC showed the highest percentage of normal seedlings, the lowest number of abnormal seedling and fresh ungerminated seeds when tested with the roll-towel method. Seed soaking with 30EC formulation of C. citratus oil increased seed germination, shoot length, root length and vigour of rice seedlings when tested with the plastic tray method. Transmission of pathogens from seed to seedling was reduced significantly by the 30EC formulation of C. citratus oil when tested with the plastic pot method. The effect of the storage life of the 30EC formulation of C. citratus oil showed that it had retained their antifungal effect till the end of the incubation period (120 days), and is able to inhibit the mycelial growth of all test pathogens to the 100% level., (Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

For decades, human activities have gradually destroyed the natural habitats of wild grapevine, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi, and nowadays this species is endangered in southern Europe. In this paper, 94 populations of this species have been localized and characterized in the Andalusian region in the Iberian Peninsula between 1989 and 2013. Location, ecological aspects, and sanitary characteristics are described. Must properties and in vitro tolerance to calcareous conditions were also checked. The paper also contains a global description of female and male individuals. Two hundred individuals from six river basin populations have been sampled, and their genetic structure analyzed by using 25 nuclear microsatellites loci to investigate the gene diversity of wild grape populations in Andalusia at two levels: total individuals and at river basin populations. Also, the genetic relationship of wild and cultivated accessions has been tested. Wild grapevine is considered the ancestor of the cultivated varieties and should be preserved as this material could be used to start breeding programs of cultivated varieties and also to restore riverbank forests, which constitute one of the worst preserved ecosystems in the area., (Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.)

The molecular techniques are the standard tool for the study of the taxonomic position and phylogenetic affinities of the lymnaeid genus Radix Montfort, 1810, and the majority of the European representatives of this taxon have been studied in this respect. However, a plethora of nominal species of Radix described from Northern Asia (Siberia and the Russian Far East) are still characterized only morphologically, raising some doubts concerning their validity. In this paper, we present the triple (morphological, molecular, and zoogeographical) evidence that there is at least one endemic species of Radix, Radix dolgini (Gundrizer and Starobogatov, 1979), widely distributed in Siberia and Western Mongolia. Phylogenetically, it is a sister species to the European R. labiata (Rossmaessler, 1835) [=R. peregra auct.], and their common ancestor most probably lived in the Pliocene, nearly 3.25Myr ago. Our results assume the existence of an extended dispersal barrier for freshwater hydrobionts between Europe and Siberia in the Late Pliocene that may be important for biogeographical explanations. Three other nominal Siberian species of Radix: R. kurejkae (Gundrizer and Starobogatov, 1979), R. gundrizeri (Kruglov and Starobogatov, 1983), and R. ulaganica (Kruglov and Starobogatov, 1983) proved to be the junior synonyms of R. dolgini., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

At the Paris Colloquium held forty years ago, and which this paper celebrates, the issue of psychosurgery had not been tackled yet. At that time psychosurgery was tainted by the controversial history of lobotomy and leucotomy. Supporters of psychosurgery at the time of the Colloquium were preparing their fourth International Conference, which was held in Madrid the following year. This represented a key characteristic of the collective, institutional and symbolic action of psychosurgery practitioners. At the end of the seventies, their strategy changed as noted below. Furthermore, we focus on the special importance of the results presented and commented on by psychosurgery supporters, including its conception and classification throughout the rhetoric historically involved (its supposed ventriloquism, its persuasive strength). Based on this view, we suggest a critical reflection encompassing old and new psychosurgery, while questioning the value of new rhetorical devices for the assessment and presentation of psychosurgery results after the surge of Deep Brain Stimulation., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

In this paper, I examine some important metaphysical lessons that are often presented as derived from two new scientific disciplines: synthetic biology and neuroscience. I analyse four of them: the nature of life, the existence of a soul (the mind-body problem), personhood, and free will. Many caveats are in order, and each 'advance' or each case should be assessed for itself. I conclude that a main lesson can nevertheless be learned: in conjunction with modern science, neuroscience and synthetic biology allow us to enrich old metaphysical debates, to deepen and even renew them. In particular, it becomes less and less plausible to consider life, mind, person, and agency as non-natural or non-physical entities., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

The paper is about the links between ethics and science, at a time (1974-2014) when the life sciences expanded rapidly. First (1974-1994), the development of a principlist ethics, set out by philosophers, sustained the research, and the scientists, expected to behave responsibly, felt like they could easily converge towards impeccable and consensual solutions to any problem arising from scientific innovations. Later on (1994-2014), however, while yielding ground to social sciences and ground work, bioethics took an empirical turn; then it became clear that behaving responsibly was compatible with a plurality of divergent normative convictions. Ethics crumbled. Local or national policies restored order, so-called bioethical laws short-circuited ethical reflection. And far from being respected as the wise men, apt to recommend the very best solutions to problems raised by new scientific advances, researchers happened to be deemed irresponsible, as some of them were suspected of lacking intellectual integrity., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

In this paper, we propose an historical survey of the expression "synthetic biology" in order to identify its main philosophical components. The result of the analysis is then used to investigate the meaning of the notion of "synthetic man". It is shown that both notions share a common philosophical background that can be summed up by the short but meaningful assertion: "biology is technology". The analysis allows us to distinguish two notions that are often confused in transhumanist literature: the notion of synthetic man and the notion of renewed man. The consequences of this crucial distinction are discussed., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

In 1959, Jacques Monod wrote a manuscript entitled Cybernétique enzymatique [Enzymatic cybernetics]. Never published, this unpublished manuscript presents a synthesis of how Monod interpreted enzymatic adaptation just before the publication of the famous papers of the 1960s on the operon. In addition, Monod offers an example of a philosophy of biology immersed in scientific investigation. Monod's philosophical thoughts are classified into two categories, methodological and ontological. On the methodological side, Monod explicitly hints at his preferences regarding the scientific method in general: hypothetical-deductive method, and use of theoretical models. He also makes heuristic proposals regarding molecular biology: the need to analyse the phenomena in question at the level of individual cells, and the dual aspect of all biological explanation, functional and evolutionary. Ontological issues deal with the notions of information and genetic determinism, "cellular memory", the irrelevance of the notion of "living matter", and the usefulness of a cybernetic comprehension of molecular biology., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

In his famous book Le hasard et la nécessité (1970), Monod claims that natural evolution is based on the interplay between chance and necessity bringing about adaptive evolutionary change. This article addresses a set of related questions about Monod's conception of chance: what does he mean when he uses the term "chance"? Does he invoke one or many different concepts of chance? What are the implications of his conception about the issue of the deterministic or indeterministic nature of the biological world? Is Monod's view of what chance is relevant in contemporary biology? This paper, structured by these four questions, aims at providing a synthetic study of the way Monod conceptualizes chance, particularly highlighting the metaphysical and epistemological implications of his conception and its value in biology today., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

Exploiting the annotation of the western clawed frog Silurana tropicalis genome, we identified a new metallothionein (MT) gene, exhibiting all the features to be considered an active gene, but with an atypical coding region, showing only 17 cysteine residues instead of the canonical 20 cysteines of vertebrate metallothioneins and two anomalous cysteine triplets. However, the presence of a gene in the genome does not ensure its effective expression. By using conventional and Real-Time PCR analyses, we demonstrated that this atypical MT is constitutively expressed throughout the life cycle of the African clawed frog Xenopus laevis; moreover, this gene is highly expressed in the adult liver, the major site of MT expression and synthesis in vertebrates. To our knowledge, the X. laevis MT described in this paper is the first sequence of a vertebrate MT showing only 17 cysteine residues, arranged in two Cys-Cys-Cys motifs. Phylogenetic analyses also demonstrated that the atypical X. laevis MT merges in the anuran clade, but is the most derived sequence among tetrapods MTs. Finally, Tajima's Relative Rate Test suggested a different evolutionary rate between the canonical X. laevis MT and this novel isoform., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

In this paper, a delayed predator-prey model with Hassell-Varley-type functional response is investigated. By choosing the delay as a bifurcation parameter and analyzing the locations on the complex plane of the roots of the associated characteristic equation, the existence of a bifurcation parameter point is determined. It is found that a Hopf bifurcation occurs when the parameter τ passes through a series of critical values. The direction and the stability of Hopf bifurcation periodic solutions are determined by using the normal form theory and the center manifold theorem due to Faria and Maglhalaes (1995). In addition, using a global Hopf bifurcation result of Wu (1998) for functional differential equations, we show the global existence of periodic solutions. Some numerical simulations are presented to substantiate the analytical results. Finally, some biological explanations and the main conclusions are included., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

The recently erected cestode order Diphyllobothriidea is unique among all tapeworm orders in that its species infect all major groups of tetrapods, including man. In the present paper, the vitellogenesis of representatives of all three currently recognized families of this order was evaluated, based on ultrastructural (transmission electron microscopy) and cytochemical (detection of glycogen) observations. Vitelline follicles of all taxa studied, i.e. Cephalochlamys namaquensis from clawed frogs (Xenopus), Duthiersia expansa from monitors (Varanus) and Schistocephalus solidus that matures in fish-eating birds, contain vitelline cells at various stages of development and interstitial cells. Developing vitellocytes are characterized by the presence of mitochondria, granular endoplasmic reticulum and Golgi complexes involved in the synthesis of shell globules and formation of shell globule clusters. Mature vitellocytes contain lipids and glycogen in different proportions. The most significant differences among the three diphyllobothriidean families were found in the presence or absence of lamellar bodies. Variations of vitelline clusters morphology and types of lipid droplets are described and discussed in relation to the presumed evolutionary history of diphyllobothriideans, which belong to the most basal cestode groups., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity., (Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.)