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We show in this paper how simple considerations about bio-arrays images lead to a peak segmentation allowing the genes activity analysis. Bio-arrays images have a particular structure and the aim of the paper is to present a mathematical method allowing their automatic processing. The differential geometry approach used here can be also employed for other types of images presenting grey level peaks corresponding to a functional activity or to a chemical concentration. The mathematical method is based on elementary techniques of differential geometry and dynamical systems theory and provides a simple efficient algorithm when the peaks to segment are isolated. [Copyright &y& Elsevier]

Résumé L’article engage une investigation historique sur l’origine de l’expression « biologie synthétique » dans le but d’en dégager les principales composantes philosophiques. Les résultats de cette analyse sont ensuite utilisés pour étendre l’examen au terme d’« homme synthétique ». On montre ainsi que les deux notions comportent l’affirmation d’une conviction philosophique commune qui peut se résumer de la façon suivante : « la biologie est de la technologie ». L’analyse de cette affirmation permet de distinguer nettement deux notions qui sont généralement confondues dans la littérature transhumaniste : celle d’homme synthétique et celle d’homme nouveau. Les conséquences de cette distinction cruciale sont discutées. 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. [ABSTRACT FROM AUTHOR]

Résumé Cet article porte sur les liens entre éthique et science, au cours de la période 1974–2014, qui est un moment de grandes avancées des sciences de la vie. Dans un premier temps (1974–1994), l’essor d’une bioéthique d’inspiration philosophique, formulée en termes de grands principes , soutient la recherche, et les savants, appelés à se conduire de façon responsable , pensent pouvoir converger vers des solutions irréprochables et consensuelles aux problèmes posés par les progrès de la science. Dans un second temps (1994–2014), cependant, avec l’entrée dans le jeu bioéthique des sciences humaines et sociales, les pratiques normatives observées sur le terrain révèlent que les attitudes dites responsables sont compatibles avec une pluralité de convictions éthiques divergentes . Alors, les politiques rétablissent un ordre, la loi court-circuite la réflexion éthique , et, loin de rester les sages que l’on croyait porteurs des meilleures solutions, les chercheurs sont accusés d’être irresponsables lorsqu’ils manquent d’honnêteté intellectuelle. 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. [ABSTRACT FROM AUTHOR]

Abstract: The authors investigated in this paper the attractiveness of a water colonized (‘positive’ breeding site) or not (‘negative’ breeding site) by larvae of Aedes aegypti on gravid females and then characterized their physicochemical properties to identify and quantify the principal components. The results showed that the water that sheltered several generations of larvae was more attractive to gravid females than water that had never been colonized. The water in a ‘positive’ breeding site contains 2.5 times more ammonium ions (NH+ 4), four times more nitrite ions (NO− 2) and 20 times more nitrate ions (NO− 3) than ‘negative’ breeding water. The authors suggest that in the ‘positive’ breeding sites, where the larvae absorb the organic matter, the turbidity of water decreases, which makes it possible for organic nitrogen to be converted into nitrites and nitrates via the nitrifying activity of the bacteria (NH+ 4 →NO− 2 →NO− 3). It is likely that chitin, while accumulating and decomposing at the bottom of the breeding site, may increase the percentage of organic carbon and ammonium ions, then reinforcing the nitrification process. Conversely, in the ‘negative’ breeding site where the conditions of evolution of the nitrifying bacteria are more restrictive, the nitrogen remains primarily in its organic form. To cite this article: F. Darriet, V. Corbel, C. R. Biologies 331 (2008). [Copyright &y& Elsevier]

Abstract: This paper describes the conditions under which autoimmune T cells enter the central nervous system to attack the local tissue. During a prodromal period preceding the onset of neurological disease, the CNS tissue is converted from its physiological immune-hostile state to an immune-friendly state. At the same time, in the peripheral immune system, activated autoimmune T cells undergo profound changes that allow them to enter through the blood-brain barrier and to finally interact with local autoantigen-presenting cells. Antigen recognition leads to T cell activation and the secretion of inflammatory mediators that are responsible for the development of the inflammatory lesions and the neurological deficits. To cite this article: H. Wekerle, C. R. Biologies 330 (2007). [Copyright &y& Elsevier]

Abstract: The Merja Zerga lagoon is a semi-enclosed marine ecosystem in which various types of human activities have been developed. This paper characterizes the biosedimentary units of the lagoon and defines a reference status of the quality and health of the macrozoobenthic communities that can be used as bioindicators of the quality of the global marine environment. Specific and functional diversity were high: 147 taxa were identified; they were distributed within seven main trophic groups. Trophic structure is dominated by the suspension-feeding bivalve Cerastoderma edule and the deposit-feeding bivalve Scrobicularia plana, while micrograzers and macroherbivores remain low. Biotic index values indicated that the site is moderately perturbed and that the benthic communities are unbalanced. Nevertheless, the communities showed a seasonal stability of abundances and a high specific richness all through the year. To cite this article: H. Bazairi et al., C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: In Triticum turgidum subsp. durum (Desf.) Husn., the utilization of in vitro anther culture is hampered by the very high frequency of albinism of the regenerated plants reaching in most cases 100%. Only in vitro ovary culture or intergeneric crosses with maize produce gynogenetic green haploid and doubled haploid plants. This paper is concerned with another very interesting method of androgenetic doubled haploid plant production, the in vitro isolated microspore culture. It is shown that this method, associated with cold alone or cold plus mannitol pre-treatments, of the spikes kept within their sheath leaves, during different times, have significant positive effects, not only on embryo production, but also on chlorophyllian plant regeneration. All pre-treatments and control taken together, a total of 16 490 embryos was obtained from microspores of two T. durum varieties, among which 9320 embryos were transferred to regeneration medium and developed 150 chlorophyllian plants. Thus a long-term (five weeks) 4 °C cold pre-treatment of the microspores could be promising for green regeneration in durum wheat. To cite this article: Z. Labbani et al., C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: This paper presents a pollen diagram from La Beunaz peat-bog (southeast of Évian, Haute-Savoie, France), which provides the first detailed record of human impact on vegetation of the southern bank of Lake Geneva since the Middle Neolithic. The radiocarbon-dated pollen profile is correlated with micro-charcoal record and archaeological data. The results suggest that several phases of deforestations since years BP occurred, in relation to human activities (agriculture, pastoralism). Tombs and vestiges of lacustrine villages indicate that the region was intensively and recurrently occupied by man during at that time. To cite this article: F. Guiter et al., C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: We measure in this paper the electrical capacitance and resistance of aerial organs of some plants, grown in the laboratory (sunflower, pumpkin, and maize, of different ages) or bought at the market (sorrel), in a range of 34 frequencies, from 40 Hz to 100 kHz. The electrospectrometric curves of the leaves aged 14 days of the dicotyledoneous studied are close to each other. They diverge from that of corn, which is monocotyledonous. The opposite organs, as the leaves or the cotyledons, of a same plant have different impedances. Beyond 14 days, the sunflower leaf gives no more any typical electrospectrometric curve. To cite this article: S. Laarabi et al., C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: The climate history can be based on several kinds of data. In the present paper, French records of grape-harvest dates in Burgundy from 1370 to 1890 were used for evaluate the climates at these various period of time. These results reveal that temperatures as high as those reached in the 1990s have occurred several times in Burgundy since 1370. Correlations between temperatures and historic data are presented. To cite this article: E. Le Roy Ladurie, C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: Seeds of pea (Pisum sativum L.) were germinated for four days over two sheets of filter paper moistened with H2O (control) and 5 mM Cd(NO3)2 or CuSO4 (treated). The relationship between heavy-metal stress and breakdown of storage compounds was studied. Germination rate and growth of radicle decreased, while the water content in stressed seeds remained around the control values. Cotyledons changed their biochemical constituents: disorders in the contents of micronutrients (Fe, Mn, Zn), free amino acids and soluble sugars were found. Decline of α-amylase activity as well as acid phosphatase were also observed, whereas β-amylase and alkaline phosphatase ones were not modified by heavy-metal treatments. These results suggest that the inhibition of seed germinations after exposure to cadmium or copper is not the consequence of starvation in water uptake by seed tissues, but may be due to a failure in the reserve mobilization process from cotyledons. To cite this article: A. Mihoub et al., C. R. Biologies 328 (2005). [Copyright &y& Elsevier]

Abstract: The heat wave that struck France in 2003 has been accompanied with an estimated 15 000 excess deaths. This paper stresses the difficulties of the epidemiology of such an event. The relevant clinical and biological information is incomplete or even inaccessible and many of the deaths are due to multiple factors. The data presently available indicate that the deaths occurred in persons already vulnerable, and that the heat wave caused a five- to eight-month loss of lifetime for the affected individuals. There is a noteworthy similarity between the profiles of this exceptional summer mortality surge, and those of many past winters when similar or larger excess mortalities have occurred without as yet eliciting much public attention. To cite this article: A.-J. Valleron, A. Boumendil, C. R. Biologies 327 (2004). [Copyright &y& Elsevier]

Marine microorganism activities are commonly assessed by bulk methods and assigned to the total cell count. The presence in significant amounts of ghost, dead, and damaged cells makes such an assignment a non-correct one. A Nucleic Acid Double Staining protocol (NADS) of fresh water bacteria (Barbesti et al., Cytometry 40 (2000) 214–218) has been adapted to resolve viable, damaged and dead cells in marine environments (Gre´gori et al., Appl. Environ. Microbiol. 67 (2001) 4662–4670). The present paper reports the first in situ application of this approach, conducted in the Bay of Marseilles in winter and spring periods at two sites with contrasted features. To cite this article: G. Gre´gori et al., C. R. Biologies 326 (2003). [Copyright &y& Elsevier]

This paper presents the MBO model for the perceived intensity of odour mixtures. This model is based on an equation previously reported by our team, intended to model the whole stimulus–response intensity curve of pure odorous compounds. The MBO model was applied to a set of published data, and compared to other published models. The results show a high modelling efficiency of the MBO model compared to other proposed equations, especially for binary mixtures exhibiting significant asymmetry of intensity for different ratios of the two components. Furthermore, the MBO model includes parameters specific to the respective effects of each component in the mixture, which may help to clarify the masking and synergy effects that are often sought in odour mixtures. [Copyright &y& Elsevier]

Due to their numerous advantages, mainly in terms of patient benefit, mini-invasive robotically assisted interventions are gaining in importance in various surgical fields. However, this conversion has its own challenges that stem from both its novelty and complexity. In this paper we propose to accompany the surgeons in their transition, by offering an integrated environment that enables them to make better use of this new technology. The proposed system is patient-dependent, and enables the planning, validation, simulation, teaching and archiving of robotically assisted interventions. The approach is illustrated for a coronary bypass graft using the daVinciTM tele-operated robot. [Copyright &y& Elsevier]