Search

For improving properties of pulp fibres, a better understanding of the relationships between its macroscopic mechanical properties, fibre ultrastructure, and properties of the wood polymers is important. This paper discusses such relations between elastic properties of fibres, their matrix structure and the wood polymer elastic constants. It is argued that an orientation of all of the wood polymers in the direction of the cellulose microfibrils is most likely. The elastic longitudinal modulus of cellulose is well described by the value of 134 GPa dominating the longitudinal fibre properties. In the transverse direction the amorphous polymers play a more important role.

The ever-increasing demand of laccases for biodelignification, industrial oxidative processes and environmental bioremediation requires the production of large quantities of enzymes at low cost. The present work was carried out to reduce laccase production costs in liquid fermentations of the white-rot fungus Pleurotus ostreatus through two different approaches. In the first, screening of fungal spent media as natural laccase inducer was performed, eliminating the presence of potentially toxic/recalcitrant and expensive exogenous inducers in the culture broth. In the latter, breeding of different strains of P. ostreatus, screened for their laccase productivity, was performed by cross-hybridisation, avoiding genetic transformation and mutagenic treatments that could produce organisms not suitable for "natural or safe processes". A laccase production level close to 80,000U/L by combining the two approaches was achieved. Autoinduction and classical breeding represent promising tools for the improvement of fungal fermentation without affecting the disposable costs that also depend on the eco-compatibility of the whole process.

Lignin in kraft pulp was extracted by enzymatic hydrolysis of the carbohydrates, acidolysis with dioxane–water–HCl (conventional method), and acidolysis with acetic acid–water–ZnCl2. The latter method was shown to extract lignin with a better yield than for conventional acidolysis and with a much lower content in impurities than for enzymatic hydrolysis. It was confirmed by 13C NMR analysis of the lignin samples that conventional hydrolysis modified the lignin polymer, causing the cleavage of some aryl–ether linkages. The cleavage was also observed on a model compound submitted to the same extraction conditions. In that respect, the acetic acid–water–ZnCl2 method was less damaging and consequently more suitable for analytical purposes. To cite this article: D. Lachenal et al., C. R. Biologies 327 (2004).

In kraft pulping, a comparatively large amount of lignin remains in the fibres after the cook. Based on various analytical techniques for lignin, such as thioacidolysis, GPC and NMR, it is suggested that lignin condensation reactions take place during the cook. The reaction seems, however, not to involve ionic intermediates as has been suggested previously but rather a one-electron mechanism with elemental sulphur as the initiator. Support for such a reaction has been found through kraft cooks in the presence of an added phenol, 2,6-xylenol, as well as through NMR analysis of kraft lignin. It was found that the added phenol is incorporated in the pulp lignin with linkages indicative of radical coupling. Furthermore, kraft lignin was found to contain substantial amounts of chemically linked fatty acids. By complementary analyses of sulphur and polysulphide in an industrial black liquor, the presence of these compounds throughout a kraft cook was demonstrated.

Oxalate is a common metabolite produced by almost all plant-pathogenic fungi. The degradation of cell wall from poplar chips and poplar sawdust by oxalate is reviewed here. Oxalate treatments decrease slightly the amount of sugars constituting hemicelluloses, but only in fibres and not in sawdust or wood chips. The examination of the cell wall ultrastructure of wood chips by transmission electron microscopy (TEM) after polysaccharide staining showed a characteristic fading of the staining of the S1/S2 and S2/S3 transition areas, supporting the idea that reactivity and organization of polysaccharides had changed after the oxalate treatments. Finally, all these changes enhanced the ability of the wood chips to be defibrated by a thermomechanical (TMP) process, as well as the further refining of the pulps. Looking at the fiber surface, it became apparent that fracture areas during the TMP pulping had moved toward the S2 layer, explaining why defibrating and refining occurred more easily, with less energy input in the process. To cite this article: V. Meyer-Pinson et al., C. R. Biologies 327 (2004).

International audience; Given the non competition of miscanthus with food and animal feed, this lignocellulosic species has attracted attention as a possible biofuel resource. However, sustainability of ethanol production from lignocelluloses biomass would imply reduction in the consumption of chemicals and/or energetic means, but also valorization of the lignocellulosic by-product remaining from enzymatic saccharification. Introduction of these by-products into a cementitious matrix could be used in manufacturing a lightweight composite. Miscanthus biomass was submitted to chemical pretreatments followed by saccharification using an enzymatic cocktail. Residues from saccharification were then mixed with a cementitious matrix. Given their mechanical properties and a good adherence between cement and by-product, the hardened materials could be used. However, the delay in the beginning of setting time is too long, which prevents the direct use of by-product into cementitious matrix. Preliminary experiments using a setting accelerator in the cementitious matrix permitted significant reduction in the setting time delay.; L’utilisation de miscanthus comme ressource potentielle pour la production de bioéthanol présente un intérêt, car cette espèce lignocellulosique n’est pas utilisée dans le domaine de l’alimentation humaine ou animale. Cependant, le maintien de cette production dans le temps exigerait une forte réduction de la consommation de produits chimiques et/ou des dépenses énergiques, mais aussi la valorisation des coproduits générés lors de la saccharification enzymatique de la biomasse aérienne. L’incorporation de ces derniers dans une matrice cimentaire, directement après la saccharification, afin d’élaborer un matériau composite allégé a été étudiée. À l’état durci, les matériaux présentent de bonnes propriétés mécaniques et une bonne adhérence entre le ciment et les coproduits. Toutefois, le retard du temps de début de prise est trop important, ce qui empêche une utilisation directe de ces coproduits. Des essais préliminaires, basés sur l’utilisation d’un accélérateur de prise, ont montré que ce retard pouvait être réduit.

14 páginas.-- 7 tablas.-- 82 referencias.-- Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.crvi.2017.01.004..-- M. Cantos et al. / C. R. Biologies xxx (2017) xxx–xx, [EN]: 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., [FR]: Pendant des décennies, les activités humaines ont progressivement détruit les habitats naturels de la vigne sauvage, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi et, de nos jours, cette espèce est menacée dans le Sud de l’Europe. Dans cet article, 94 populations de cette espèce ont été localisées et caractérisées en Andalousie, dans la péninsule Ibérique, entre 1989 et 2013. L’emplacement, les aspects écologiques et les caractéristiques sanitaires sont décrits. Les propriétés du moût et la tolérance in vitro aux conditions calcaires ont été également vérifiées. L’étude contient pareillement une description globale des individus féminins et masculins. Deux cents individus de six populations de bassins fluviaux ont été échantillonnés et leurs structures génétiques analysées en utilisant 25 microsatellites nucléaires pour étudier la diversité génétique des populations de raisins sauvages en Andalousie à deux niveaux : les individus totaux et les populations de bassins fluviaux. De plus, la relation génétique des accessions sauvages et cultivées a été testée. La vigne sauvage est considérée comme l’ancêtre des variétés cultivées et elle doit être préservée, car elle pourrait être utilisée pour lancer des programmes de sélection de variétés cultivées et pour restaurer les forêts riveraines, qui constituent l’un des écosystèmes les plus préservés de la région., We would like to thank the Junta de Andalucía (OG-094/04 project) and Consejo Superior de Investigaciones Científicas (201140E122 project) for financial support.

The story of French epidemiology dates back to Daniel Bernoulli (1760), with regard to mathematical epidemiology,and to Pierre-Charles Louis (1838), with regard to 'numerical medicine', the ancestor of the modern evidence-based medicine. This thematic issue samples some of the recent issues of modern epidemiology: biostatisticians have developed a series of specialized techniques to encover the risk factors and to measure the proportion of the disease frequency they can account for (one paper). Epidemiology of chronic diseases is now providing new insights into the tricky relationships between environmental, genetic factors, and diseases (four papers). Epidemiology is not just concerned with diseases. All aspects of human biology and physiology for which a population approach is necessary, are concerned: one paper deals with the case of fecundity and fertility, which are studied by both demographic and epidemiological approaches. One of the roles of epidemiology is to bring rational answers to disputed issues in public health, such as the hazards of postmenopausal hormonal therapy (one paper). Finally, the power of mathematics is increasingly used to understand better the dynamics of infectious diseases (two papers).

In this paper, a new algorithm is presented, which makes possible multilevel comparison of BLOSUM protein substitution matrices based on data from different groups of organisms. As an example, a comparison between substitution matrices based on data from two groups of bacterial genomes with different GC content is presented. Our approach includes evaluating the number of amino acid pairs in BLOCKS databases created separately for the two groups of bacteria using protein sequences deposited in the COG database. Differences of distributions of amino acid pair counts are tested using the chi-squared based G-test. Different analysis levels make it possible to distinguish different patterns of amino acid substitution. Application of the algorithm reveals statistically significant differences in amino acid substitution patterns between AT-rich and GC-rich groups of bacterial organisms. The differences are particularly visible in the overall substitution pattern, amino acid conservation pattern and in comparison of substitution patterns for single amino acids. The algorithm presented in this paper can be considered a novel method for multi-level comparison of amino acid substitution patterns. The presented approach is not limited to bacterial organisms and BLOSUM substitution matrices. Statistically significant differences between substitution patterns in the two groups of bacterial organisms with respect to amino acid conservation pattern can be the evidence of different rate of evolutionary change between AT-rich and GC-rich bacterial organisms.

The set of these two theoretical papers offers an alternative to the hypothesis of a primordial RNA-world. The basic idea of these papers is to consider that the first prebiotic systems could have been networks of catalysed reactions encapsulated by a membrane. In order to test this hypothesis it was attempted to list the main obligatory features of living systems and see whether encapsulated biochemical networks could possibly display these features. The traits of living systems are the following: the ability they have to reproduce; the fact they possess an identity; the fact that biological events should be considered in the context of a history; the fact that living systems are able to evolve by selection of alterations of their structure and self-organization. The aim of these two papers is precisely to show that encapsulated biochemical networks can possess these properties and can be considered good candidates for the first prebiotic systems. In the present paper it is shown that if the proteinoids are not very specific catalysts and if some of the reactions of the network are autocatalytic whereas others are not, the resulting system does not reach a steady-state and tends to duplicate. In the same line, these biochemical networks possess an identity, viz. an information, defined from the probability of occurrence of these nodes. Moreover interaction of two ligands can increase, or decrease, this information. In the first case, the system is defined as emergent, in the second case it is considered integrated. Another property of living systems is that their behaviour is defined in the context of a time-arrow. For instance, they are able to sense whether the intensity of a signal is reached after an increase, or a decrease. This property can be mimicked by a simple physico-chemical system made up of the diffusion of a ligand followed by its chemical transformation catalysed by a proteinoid displaying inhibition by excess substrate. Under these conditions the system reacts differently depending on whether the same ligand concentration is reached after an increase or a decrease.

In this paper we present a travelling-wave analysis of a mathematical model describing the growth of a solid tumour in the presence of an immune system response. From a modelling perspective, attention is focused upon the attack of tumour cells by tumour infiltrating cytotoxic lymphocytes (TICLs), in a small multicellular tumour, without necrosis and at some stage prior to (tumour-induced) angiogenesis. As we have shown in previous work, for a particular choice of parameters, the underlying reaction–diffusion–chemotaxis system of partial differential equations is able to simulate the well-documented phenomenon of cancer dormancy by depicting spatially heterogeneous tumour cell distributions that are characterized by a relatively small total number of tumour cells. This behaviour is consistent with several immunomorphological investigations. Moreover, the alteration of certain parameters of the model is enough to induce bifurcations into the system, which in turn result in tumour invasion in the form of a standard travelling wave. The work presented in this paper complements the bifurcation analysis undertaken by Matzavinos et al. [Math. Med. Biol. IMA 21 (2004) 1–34] and establishes the existence of travelling-wave solutions for the system under discussion by promoting the understanding of the geometry of an appropriate phase space. To cite this article: A. Matzavinos, M.A.J. Chaplain, C. R. Biologies 327 (2004).

As classically defined by Macdonald in the early 1950s, for the case of diseases with one vector and one host, the Basic Reproduction Number, R0, is defined as the number of secondary infections caused by a single infective of the same type (vector or host) during its infectiousness period in an entirely susceptible population. In the case of a disease which has one vector and one host, it is easy to show that R0 coincides with the threshold for the establishment of an endemic state: if R0 > 1 (< 1), the disease can invade (cannot invade) the host population. In this paper we examine various epidemic situations in which there are more than one vector and/or host. We show that in those more complex systems it is not possible to deduce a single R0 but rather a threshold for infection persistence which is a composite of several quantities closely related to the classical expression of R0. Another definition of R0 given by Diekmann, Heesterbeek and Metz, and denoted in this paper R0NGO is discussed and applied as an alternative to calculate the thresholds for infection establishment.

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.

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 4500–4600 m. 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.

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.

Metamorphosis was a key innovation in insect evolution, wherein the individual acquires characteristic adult features and stops molting during postembryonic development. The ancestral metamorphosis mode was hemimetaboly, in which the embryogenesis gives rise to a first instar nymph with the essential adult body structure. The nymphs grow gradually and the final molt to the adult stage completes the formation of functional genitalia and wings. The metamorphosis mode known as holometaboly emerged from hemimetaboly, which is characterized by embryogenesis that produces a larva with a body form that may be substantially different from that of the adult. The larva grows through various stages until molting to the pupal stage, which bridges the gap between the morphologically divergent larva and that of the winged and reproductively competent adult. In the hemimetabolan and holometabolan modes, metamorphosis is regulated by two hormones: the juvenile hormone (JH) and the ecdysone, plus its biologically active derivative, 20-hydroxyecdysone (20E). 20E is a steroid, and its main role is to promote the successive molts, including the metamorphic one, whereas JH is a terpenoid, whose function is to repress metamorphosis [1] . The action of these hormones is underpinned by the mechanisms that transduce the hormonal signal through a pathway of gene activation. The 20E signaling pathway was first described in the 1990s [2] , whereas the most important details of the JH pathway were unveiled recently. Important components of the JH signaling pathway are the JH receptor, which is the basic helix–loop–helix-Per-ARNT-Sim (bHLH-PAS) protein known as methoprene tolerant (Met), to which JH binds, as unveiled by Jindra's group in the 2010 decade. Another important component is Taiman, also a bHLH-PAS protein that plays the role of co-receptor. Finally, the transcription factor Kruppel homolog 1 (Kr-h1) is the main transducer of the antimetamorphic signal of JH [1] . Kruppel homolog 1 Kr-h1 was discovered in Drosophila melanogaster as a gene with structural similarity to the segmentation gene Kruppel, with which it shares the zinc-finger motifs and amino acid spacers connecting them. The first evidence that connected Kr-h1 and JH was also obtained in D. melanogaster. In this fly, the adult abdominal epidermis derives from larval histoblasts, which start proliferating after puparium formation. The experiments of Ashburner in 1970 showed that administration of JH prior to the prepupal stage prevents the normal differentiation of the abdominal epidermis, and the bristles that should be formed in the adult are shorter or lacking. In 2008, the experiments of Minakuchi and coworkers indicated that Kr-h1 expressed ectopically in the abdominal epidermis during metamorphosis of D. melanogaster also resulted in missing or short bristles, thereby suggesting that Kr-h1 mediates the antimetamorphic action of JH. New experiments of Minakuchi and coworkers carried out in the beetle Tribolium castaneum in 2009 showed that RNAi depletion of Kr-h1 in young larvae caused a precocious larval–pupal transformation, providing clear evidence that Kr-h1 represses metamorphosis and works downstream from Met in the JH signaling pathway. The antimetamorphic action of Kr-h1 was generalized to hemimetabolans in two parallel papers published in 2011 and conducted, respectively, in the cockroach Blattella germanica by Lozano and Belles, and the bugs Pyrrhocoris apterus and Rhodnius prolixus by Konopova and coworkers. In these two studies, RNAi experiments showed that Kr-h1 depletion in nymphs in the penultimate or antepenultimate nymphal stage triggers precocious metamorphosis [1] ( Fig. 1 A). E93 E93 is an early gene in the ecdysone signaling cascade that is specifically expressed in late prepupae of D. melanogaster. As shown by the groups of Thummel and Baehrecke in the 1990 decade, the gene encodes for a protein with RHF domains significantly similar to pipsqueak motifs, which was found to be a key player in the degeneration process of the salivary glands during D. melanogaster metamorphosis. However, the action of E93 in metamorphosis is not restricted to the regulation of degeneration processes, given that it also plays morphogenetic roles. In 2012 Mou and coworkers observed that E93 is widely expressed in adult cells of the pupa of D. melanogaster, where it is required for patterning processes. Studying the induction of the Distal-less (Dll) gene within bract cells of the pupal leg using epidermal growth factor (EGF) receptor signaling, Mou and coworkers found that E93 causes Dll to become responsive to EGF receptor signaling, thus indicating that E93 is both necessary and sufficient for determining this switch. These results suggested that E93 controls the responsiveness of many other target genes and that it is generally required for patterning during metamorphosis. Subsequent RNAi experiments reported by Urena and coworkers in 2014 showed that E93-depleted D. melanogaster larvae are able to pupate but die at the end of the pupal stage. In T. castaneum, E93 depletion by RNAi prevented the pupal–adult transition, resulting in the formation of a supernumerary second pupa. Similar results were obtained in the cockroach B. germanica, where E93 depletion in nymphs prevented the nymphal–adult transition, giving rise to repeated supernumerary nymphal instars ( Fig. 1 B). The same year, Belles and Santos showed that the expression of E93 in juvenile nymphs of B. germanica is inhibited by the transcription factor Kr-h1, thus uncovering the essential mechanism by which JH represses metamorphosis, which was named MEKRE93 pathway [3] . The MEKRE93 pathway in hemimetabolan species The observation that Kr-h1 represses E93 expression led to propose the MEKRE93 pathway as the essential axis regulating insect metamorphosis. Accordingly, in nymph–nymph transitions, JH acts through its receptor Met-Taiman to induce the expression of Kr-h1, while Kr-h1 represses the expression of E93. In contrast, the decline of JH production in the final juvenile stage interrupts Kr-h1 expression, E93 becomes de-repressed, thus triggering adult morphogenesis ( Fig. 2 A) (Belles and Santos, 2014). RNAi experiments in B. germanica by the same authors also revealed that E93 depletion increases Kr-h1 expression, thus indicating that Kr-h1 and E93 are reciprocally repressed. The inhibitory action of Kr-h1 upon E93 expression was corroborated two years later in the holometabolan T. castaneum by Urena and coworkers, which extended the MEKRE93 pathway framework to holometabolan metamorphosis. The MEKRE93 pathway in holometabolan species The main difference between the hemimetabolan and holometabolan metamorphoses is the regulation and function of the Broad complex (BR-C) zinc-finger transcription factors. In hemimetabolan species, BR-C is mainly involved in promoting the growth of wing primordia. For example, this was shown in B. germanica by Huang and coworkers in 2013, who additionally reported that BR-C expression is induced by JH and Kr-h1 during juvenile stages. One year later, Urena and coworkers found that BR-C is repressed by E93 in the metamorphic transition. Furthermore, RNAi studies made in 2019 by the group of Mito and Noji in the cricket Gryllus bimaculatus, a hemimetabolan species, confirmed the mentioned interactions, and additionally discovered that BR-C and Kr-h1 are reciprocally activated. In sharp contrast, and as shown mainly by the group of Riddiford in the decade of 1990, BR-C triggers the formation of the pupal stage in holometabolan species, where JH inhibits the expression of BR-C during larval stages and stimulates BR-C expression after pupal commitment ( Fig. 2 B). In 2019, Chafino and co-workers showed that E93 is involved in triggering the pupal stage, as it promotes BR-C expression in T. castaneum. The whole data indicates that the MEKRE93 pathway is conserved in the holometabolan species, which added the E93/BR-C interaction loop to the ancestral (hemimetabolan) pathway during the evolutionary transition from hemimetaboly to holometaboly ( Fig. 2 C).

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.

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.

In his famous book Le hasard et la necessite (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.

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.

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.

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 Santissima 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.

This paper reports the role of darkling beetles Pimelia laevigata costipennis and Hegeter amaroides (Tenebrionidae) as intermediate hosts of spiruroid nematodes parasites of the black rat and house mouse of El Hierro (Canary Islands). Larvae of spiruroid species were found in the two tenebrionids (18.1% in P. l. costipennis, 7.8% in H. amaroides), Streptopharagus greenbergi being predominant in both (16.1% and 7.1%, respectively), ahead of Mastophorus muris and Gongylonema type larva. The larval stages of S. greenbergi are described for the first time, and adult worms were obtained experimentally from an infected laboratory rat, allowing the identification of the species. Morphometric measurements of experimental adults match those of adults detected in naturally infected rats on the island. Molecular data for S. greenbergi, and the ITS nucleotide sequence of the genus Streptopharagus are also provided for the first time. After the isolation of S. greenbergi DNA and amplification of the ITS region, the ITS1 of this spirocercid was sequenced and deposited in the GenBank database.

Plant organs grow in coordinated and continuous way. Such growth is of a tensor nature, hence there is an infinite number of different directions of growth rate in each point of the growing organ. Three mutually orthogonal directions of growth can be recognized in which growth achieves extreme values (principal directions of growth [PDGs]). Models based on the growth tensor have already been successfully applied to the root and shoot apex. This paper presents the 2D model of growth applied to the arabidopsis leaf. The model employs the growth tensor method with a non-stationary velocity field. The postulated velocity functions are confirmed by growth measurements with the aid of the replica method.

Quorum sensing is a decision-making process used by decentralized groups such as colonies of bacteria to trigger a coordinated behavior. The existence of decentralized coordinated behavior has also been suggested in the immune system. In this paper, we explore the possibility for quorum sensing mechanisms in the immune response. Cytokines are good candidates as inducer of quorum sensing effects on migration, proliferation and differentiation of immune cells. The existence of a quorum sensing mechanism should be explored experimentally. It may provide new perspectives into immune responses and could lead to new therapeutic strategies.

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.

International audience; Why was sexual selection so important to Darwin? And why was it de-emphasized by almost all of Darwin's followers until the second half of the 20th century? These two questions shed light on the complexity of the scientific tradition named "Darwinism". Darwin's interest in sexual selection was almost as old as his discovery of the principle of natural selection. From the beginning, sexual selection was just another "natural means of selection", although different from standard "natural selection" in its mechanism. But it took Darwin 30 years to fully develop his theory, from the early notebooks to the 1871 book The Descent of Man, and Selection in Relation to Sex. Although there is a remarkable continuity in his basic ideas about sexual selection, he emphasized increasingly the idea that sexual selection could oppose the action of natural selection and be non adaptive. In time, he also gave more weight to mate choice (especially female choice), giving explicit arguments in favor of psychological notions such as "choice" and "aesthetic sense". But he also argued that there was no strict demarcation line between natural and sexual selection, a major difficulty of the theory from the beginning. Female choice was the main reason why Alfred Russel Wallace, the co-discoverer of the principle of natural selection, engaged in a major controversy with Darwin about sexual selection. Wallace was suspicious about sexual selection in general, trying to minimize it by all sorts of arguments. And he denied entirely the existence of female choice, because he thought that it was both unnecessary and an anthropomorphic notion. This had something to do with his spiritualist convictions, but also with his conception of natural selection as a sufficient principle for the evolutionary explanation of all biological phenomena (except for the origin of mind). This is why Wallace proposed to redefine Darwinism in a way that excluded Darwin's principle of sexual selection. The main result of the Darwin-Wallace controversy was that most Darwinian biologists avoided the subject of sexual selection until at least the 1950s, Ronald Fisher being a major exception. This controversy still deserves attention from modern evolutionary biologists, because the modern approach inherits from both Darwin and Wallace. The modern approach tends to present sexual selection as a special aspect of the theory of natural selection, although it also recognizes the big difficulties resulting from the inevitable interaction between these two natural processes of selection. And contra Wallace, it considers mate choice as a major process that deserves a proper evolutionary treatment. The paper's conclusion explains why sexual selection can be taken as a test case for a proper assessment of "Darwinism" as a scientific tradition. Darwin's and Wallace's attitudes towards sexual selection reveal two different interpretations of the principle of natural selection: Wallace's had an environmentalist conception of natural selection, whereas Darwin was primarily sensitive to the element of competition involved in the intimate mechanism of any natural process of selection. Sexual selection, which can lack adaptive significance, reveals this exemplarily.

International audience; As part of a breeding strategy applied to pea (Pisum sativum L.), we propose the use of modelling as a tool for studying flowering time. The pea, both a crop and a model species for developmental processes, represents a valuable tool for systems biology approaches. A preliminary computational model for flowering control was previously developed based on genetic and physiological approaches. This paper discusses possible improvements of the model based on recent molecular advances on the regulation of flowering in peas and the model species Arabidopsis thaliana. A combination of a genetic approach together with agroecophysiological models that are not based on genotype, built into a complete model for flowering time prediction is also proposed. This complete model should allow an accurate prediction of flower initiation and also provide an integrative tool that will be useful for various purposes, from genetic networks to crop models.

In our global world, the increasing complexity of social relations and transport infrastructures are key factors in the spread of epidemics. In recent years, the increasing availability of computer power has enabled both to obtain reliable data allowing one to quantify the complexity of the networks on which epidemics may propagate and to envision computational tools able to tackle the analysis of such propagation phenomena. These advances have put in evidence the limits of homogeneous assumptions and simple spatial diffusion approaches, and stimulated the inclusion of complex features and heterogeneities relevant in the description of epidemic diffusion. In this paper, we review recent progresses that integrate complex systems and networks analysis with epidemic modelling and focus on the impact of the various complex features of real systems on the dynamics of epidemic spreading.

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.

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.

In this paper, we build up an individual-based model (IBM) that describes the aggregative behavior in phytoplankton. The processes in play at the individual level (an individual = a phytoplankton cell) are: a random dispersal, a displacement due to the net effect of cells present in a suitable neighborhood (spatial interactions) and a branching (cell division and death). The IBM model provides a virtual world where phytoplankton cells appear to form clusters. Using this model, we explore the spatial structure of phytoplankton and present some numerical simulations that help the understanding of the aggregation phenomenon. To cite this article: N. El Saadi, A. Bah, C. R. Biologies 329 (2006).

The rapid development of new concepts and tools has led to a change in the way in which researchers carry out nutrition-related research. Obesity is determined by the interaction between predisposing genetic and environmental aspects, but at present the gene–gene and gene–environment interactions contributing to the development of this complex disease cannot be analysed in detail. The purpose of the present paper is to provide some examples of the knowledge that is available in the field of obesity genetics, and also the new strategies being developed that are aimed at studying the relative contribution of numerous genes to obesity and their responses to environmental changes. In the rare cases of monogenic obesities in which a major gene is the cause the molecular approach has proved extremely powerful in the identification of the genes responsible and in defining new syndromes. However, in the common forms of obesity (polygenic obesity) most studies have analysed genotype–phenotype associations without sometimes taking into account the influence of environmental factors (diet, sedentary lifestyle). Among the aspects limiting this integrated approach to obesity are the difficulty of having large enough samples and the expansion of biocomputing tools developed for accessing the question of multiple interactions with noa priorihypotheses. This picture is rapidly changing. Large databases of clinical data and DNA and biological sample banks with more precise environmental information and patient phenotypes are being compiled. The capacity for studying multiple genes simultaneously at the DNA or RNA levels is also possible. Finally, the tremendous progress in biocomputing will allow the integration of these different types of data (relating to environment, phenotype, genotype, gene expression) and will improve the ability to deal with this complex disease.

Two aspects of psychology and physiology of time are dealt with in this paper: the way time perception was increasingly studied during the 19th century by scientists, including many physicists, and the way the temporal properties of the nervous system were discovered and explored by physiologists. The neurophysiological correlation between both aspects still remains to be explained. The relationship between time consciousness and consciousness mechanisms was often guessed by philosophers and looked for by scientists. It remains a major subject of investigation in neuroscience as well as a philosophical puzzle. To cite this article: C. Debru, C. R. Biologies 329 (2006).

In 1936 Sir Henry Dale of London and Professor Otto Loewi from Graz shared the Nobel Prize in Physiology or Medicine for their work on chemical neurotransmission. This paper uses much unpublished archival material to augment an examination of Dale's work, from his discovery of naturally occurring acetylcholine in 1913, through to evidence of its role as a neurotransmitter at autonomic ganglia, post-ganglionic parasympathetic nerve terminals and the neuromuscular junction.

In spite of the historical importance of the research that, in the second half of the 18th century, led Luigi Galvani (1737–1798) to lay down the foundation of modern electrophysiology, his scientific personality is largely misrepresented in science history and in popular imagery. He is still considered as a pioneer that by chance incurred some surprising experimental observations and was incapable of pursuing his research in a coherent way. In contrast with these views, Galvani was a high-standard scientist who succeeded, with the strength of experimental science, in demonstrating, in animals, electricity in a condition of disequilibrium between the interior and the exterior of excitable fibres. This electricity, called ‘animal electricity’, was deemed responsible for nerve conduction. By studying the scientific endeavours of Galvani, through his published and unpublished material, and by situating them in the historical context of the physiology of the Enlightenment, this paper attempts to trace the elusive and complex path that led Galvani to his extraordinary discovery. To cite this article: M. Piccolino, C. R. Biologies 329 (2006).

We consider some mathematical issues raised by the modelling of gene networks. The expression of genes is governed by a complex set of regulations, which is often described symbolically by interaction graphs. Once such a graph has been established, there remains the difficult task to decide which dynamical properties of the gene network can be inferred from it, in the absence of precise quantitative data about their regulation. In this paper we discuss a rule proposed by R.Thomas according to which the possibility for the network to have several stationary states implies the existence of a positive circuit in the corresponding interaction graph. We prove that, when properly formulated in rigorous terms, this rule becomes a theorem valid for several different types of formal models of gene networks. This result is already known for models of differential or boolean type. We show here that a stronger version of it holds in the differential setup when the decay of protein concentrations is taken into account. This allows us to verify also the validity of Thomas' rule in the context of piecewise-linear models and the corresponding discrete models. We discuss open problems as well., Comment: To appear in Notes Comptes-Rendus Acad. Sc. Paris, Biologie

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.

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.

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 17.4 x 10(6) 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 degrees C cold pre-treatment of the microspores could be promising for green regeneration in durum wheat.

This paper investigates impacts of the creation of Marine Protected Areas (MPAs), in both economic and biological perspectives. The economic indicator is defined as the sum of discounted benefits derived from exploitation of the resource in the fishery sector, assumed to be optimally managed. The biological indicator is taken as the stock density of the resource. The basic fishery model (C.W. Clark, Mathematical Bioeconomics: The Optimal Management of Renewable Resources, second ed., John Wiley and Sons, New York, 1990) will serve as a convenient benchmark in comparing results with those that are derived from a model of two patchy populations (cf. R. Hannesson, Marine reserves: what would they accomplish, Mar. Resour. Econ. 13 (1998) 159). In the latter, a crucial characteristic is the migration coefficient with describes biological linkages between protected and unprotected areas. A set of situations where both economic and biological criteria are enhanced, after introducing a MPA, is presented. These results are obtained with the help of numerical simulations. To cite this article: D. Ami et al., C. R. Biologies 328 (2005).

The aim of this paper is contributing to the study of the exploitation of the European eel (Anguilla anguilla) in the basin of the French river 'Adour'. This exploitation constitutes the basis of the economy of local professional fishermen, who have recently noticed a diminution of the hunting of elvers. In order to design a sustainable exploitation strategy, we must know as much as possible about eel life cycle. For that purpose, we build a model to describe a phase of eels evolution, their migration upstream the river. Our model is based on the biological details of eels behaviour and constitutes a virtual laboratory, useful to test different hypotheses about eels migration.

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 alpha-amylase activity as well as acid phosphatase were also observed, whereas beta-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.

Epidemiology and heat waves: analysis of the 2003 episode in France. 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 ave occurred without as yet eliciting much public attention.

The paper provides a mathematical study of a model of urban dynamics, adjusting to an ecological model proposed by Lotka and Volterra. The model is a system of two first-order non-linear ordinary differential equations. The study proposed here completes the original proof by using the main tools such as a Lyapunov function.

In this paper we present an overview of the main strategies for physicochemical fractionation, sulphur- and chlorine-free delignification, and intelligent characterisation of various types of plant fibres, which have been experimentally investigated, as well as further developed and assessed by this group over the last ten years. To cite this article: E. Avgerinos et al., C. R. Biologies 327 (2004).

In this paper we consider cell cycle models for which the transition operator for the evolution of birth mass density is a simple, linear dynamical system with a stochastic perturbation. The convolution model for a birth mass distribution is presented. Density functions of birth mass and tail probabilities in n-th generation are calculated by a saddle-point approximation method. With these probabilities, representing the probability of exceeding an acceptable mass value, we have more control over pathological growth. A computer simulation is presented for cell proliferation in the age-dependent cell cycle model. The simulation takes into account the fact that the age-dependent model with a linear growth is a simple linear dynamical system with an additive stochastic perturbation. The simulated data as well as the experimental data (generation times for mouse L) are fitted by the proposed convolution model.

Understanding the regulation of gene control networks and their ensuing dynamics will be a critical component in the understanding of the mountain of genomic data being currently collected. This paper reviews recent mathematical modeling work on the tryptophan and lactose operons which are, respectively, the classical paradigms for repressible and inducible operons.

This paper suggests three additions to the Hildebrand method for gait-pattern specification. The first allows an extension of this method by the use of the forelimb as reference. Thus, dataset could be gathered indifferently from fore or hindlimbs cycles to identify a symmetrical gait or compare gaits of diverse species. On the basis of Hildebrand's definitions, the second suggestion permits to check the proportion of symmetrical and asymmetrical gaits adopted by different individuals of one or different species. The third addition makes a graphical clear-cut between four basic modes of gallops: rotary, transverse, half-bound and bound. These additions will facilitate extensive data comparison either to evaluate the range of variation within a single species or to specify the preferred gaits in diverse species. To cite this article: S. Renous et al., C. R. Biologies 327 (2004).

Regarding the present rate of species extinction, preservation of biodiversity has become a prerequisite to achieve sustainable development. Among major challenges an urgent need in research in biological conservation is required to reach this goal. Protected areas deserve special importance due to their relevance for development of research both in fundamental and applied ecology. This papers aims at making a critical review of possibilities and priorities in conservation ecology in these areas.