Morphology of the regiones ethmoidalis and orbitotemporalis in Galea musteloides Meyen 1832 and Kerodon rupestris (Wied-Neuwied 1820) (Rodentia: Caviidae) with comments on the phylogenetic systematics of the Caviidae

The present study describes the fetal regions ethmoidalis and orbitotemporalis of the cranium of Galea musteloides and Kerodon rupestris and compares them with Galea spixii and Cavia porcellus . The fetal crania of these representatives of the Caviinae were serially sectioned and 3D plate reconstructions were built. For a broader scope, serially sectioned heads of the caviomorph taxa Hydrochaeris hydrochaeris and Dasyprocta leporina were also examined. The ethmoidal and orbitotemporal regions of the cranium provides characters that are pertinent to the discussion of systematics of the Caviinae. Nine cranial characters were identified as being significant and discussed phylogenetically. Taking the monophyly of the Cavioidea as given, two characters are autapomorphic for the genus Galea: the reduction of the crista semicircularis and the lacrimale forming the 'arco antorbitario' (Kraglievich 1930). Cavia is the sister group of Galea; synapomorphic characters are the extent of the processus palatinus medialis of the praemaxillare and the presence lamina pterygoidea of the alisphenoid. There were no apomorphic characters of the structural complexes examined that could support the Caviinae. The reduced and nonperforated alisphenoid is an autapomorphic feature of the Caviidae. The division of the nasoturbinale is evidence for a sistergroup relationship of the Hydrochaeridae and the Caviidae. Autapomorphic characters for the Cavioidea include the ventrolateral opening of the organon vomeronasale and the lateral prolongation of the lacrimale.     

From the creation of the Veterinary Schools to the evolution of the notion of contagion in the 19th and 20th centuries

The creation of the Veterinary Schools in the 18th century would reveal a plethora of scientists, some of whom would be the precursors of Pasteur, some rivals, others followers collaborators or friends of the Master. Among the precursors let us name Chabbert, Huzard, Girard, Delafond, Renault, Toussaint, Galtier ; among the rivals: Chauveau, Arloing, Cornevin and Thomas; among the followers, collaborators or friends of Pasteur: Bouley, at first a resolute spontaneist, then the most fervent in defense of Pasteur (President of the Academy of Medicine and of the Academy of Sciences) and Nocard, Director of the School in Alfort, an important collaborator of Pasteur. Later, there was Leclainche, who created the International Office of Epizootics, and who was President of the Academy of Sciences; Guérin, who with Calmette developed the BCG vaccination; Ramon, the father of anatoxins (vaccines against diphtheria, and tetanus, combined vaccines, adjuvants to immunity). Thus, the creation of the Veterinary Schools contributed not only to the evolution of the notion of contagion, to the amelioration of animal health and the economics of agricultural production, but also to serious advances in human care, and to the protection of public health.     

Style v dans le bassin du Douro: Tradition et changement dans les graphies des chasseurs du Paléolithique Supérieur européen

The documentation of some figures of hoofed in Siega Verde on panels of palaeolithic style and its stylistic references in the whole south of Europe, constitutes the starting point of the reflection on the presence of style v in the outdoors sites of the peninsular occident. In the Douro's region exists a richer documentation than the habitual in Europe: the outdoors panels of Côa and Siega Verde, the engravings on palaeolithic figures of La Griega, the paintings with direct chronologies of Ojo Guareña, the decorated plaquettes of the level 4 of Fariseu and the pebbles and plaquettes of Estebanvela. Painting in the caverns, outdoors and cave engravings and mobile art, with good references of absolute chronology between 11,500 BP and 9000 BP that confirm the continuity of the Palaeolithic art. If we compare the data of the peninsular occident with those of the north, those of Levant and those that begin to be known in Andalusia, the coincidence of dates is astonishing. In the same way if we compare these ones with the dates of the South of France and Italy. The external art of the western facade of the Iberian Peninsula possesses not only a unite palaeolithic contrasted sequence but rather it also puts in evidence the reality of the recurrent and continued locations in the whole sector during 30,000 years.Above the 11,000 BP, the transformations of the hunter groups begin to be evident in the whole south of Europe and the graphics demonstrate these changes, with a progressive transformation of contents and style that leads to a bigger schematization. The interesting cohabitation among naturalism and schematism that demonstrate the direct dates of C¹⁴, apparent a progressive transformation that discards radical ruptures between the social and graphic world of the palaeolithic hunters and their heirs.     

Influence of Stream Profile and Abiotic Factors on the Performance and Residual Dosages of Two Commercial Formulations of Bacillus thuringiensis subsp. israelensis During a 2-Year Experiment

Recently, results of a 3-year study showed the importance of abiotic factors such as water temperature, stream discharge and the hyporheic zone on the behaviour, performance and loss of the residual dosages (amount of the injected dosage left at each station) of two commercial liquid formulations of Bacillus thuringiensis subsp. israelensis ( Bti ), Teknar HP-D and Vectobac 1200L. Experiments were performed in the same stream and under environmental conditions that allowed comparisons of results between formulations. To improve our understanding of the influence of abiotic factors on the behaviour and the performance of these formulations, a 2-year experiment using the same products was conducted in another river characterized by a much different profile, higher discharges and colder temperatures. A field procedure based on a system of gutters located on the bank of the river already used in the previous 3-year experiment was utilized. Black fly larval mortalities were recorded along the river at different distances (stations) to evaluate the behaviour and the performance of the products while water samples taken at the stations were tested in the laboratory against mosquito neonate larvae to evaluate the residual dosages of Bti at each station. Results showed that higher residual dosages of the Vectobac 1200L were recovered compared to Teknar HP-D along the river. Although higher dosages were recovered, higher mortality was observed only for the Vectobac 1200 L in high discharge conditions. As seen before, the hyporheic zone (interstitial water between the streambed and groundwater) produced a major loss of the dosages in the first meters of the river. But because of the river profile, the hyporheic zone had a lesser effect on the loss of the dosages further in the river resulting in very long carries for both Teknar HP-D and Vectobac 1200L.     

Le passage vers l’Atlantique : le processus de néolithisation en Algarve (sud du Portugal)

The late beginning of the research on the neolithisation in the Algarve (southern Portugal) has been providing, as a paradox, excellent conditions for the establishment of interdisciplinary research and the test of working hypotheses. The systematic projects put forward by the University of Algarve permit us today to conclude on a preliminary basis for the formation of a Neolithic enclave at ca. 5500 cal BC, centred in the coastal territories of the region. This enclave is fully Neolithic in economic terms and it is the westernmost extension of the Mediterranean Cardial. However, some specific features of these first Neolithic groups’ artefactual items (such as pottery morphology and style and some technological aspects of chipped stone production) indicate the existence of phenomena of partial reformulation of their material cultures. According to the presently available data, this complex process seems to have occurred in similar traits also in Andalucia and coastal Morocco, that is, at the moment of the passage to the Atlantic. This individualization within the Neolithic of Cardial tradition is the equivalent to the same general cultural phenomena that have been responsible for the formation, for example, of the so-called “Franco-Iberian Cardial” or “Tirrenic Cardial” at the time of settling of the Neolithic groups in these regions.     

Phytogeographical and phenological comparison of the Meuse and the Saône valley meadows (France)

The meadows of the floodplains of the Saône and the Meuse contain similar ecosystems subject to regular winter and spring flooding. The floristic and faunistic biodiversity decreases with the intensification of agricultural practices. The plant communities show the same zonation along a topographic gradient and have similar floristic progression. Thus, the climatic, biogeographic, human and soil factors have determined the floristic particularities of each valley. The floristic affinities of the two floodplains permitted the comparison of the phenological development of fourteen plant species. Many gaps in the development of species have been observed. These could be explained by the climatic differences betwen the two valleys (sub-Mediterranean influences in the Saône and sub-Atlantic in the Meuse), the existence of different types of soils in each valley (sand part more important in the Saône) and the occurrence of specific ecotypes in each valley.     

A discrete probability model of information support during early embryonic development

A percolation model of the diffuse redistribution of morphogenetic information in early regulative development is analyzed. It is demonstrated that the statistical average values of cell connectedness remaining below the percolation threshold of the spatial redistribution of developmental determinants do not provide for the formation of cell structures of the necessary size. The average number of cell interactions should exceed the percolation threshold, and, therefore, the carriers of morphogenetic information in early development can move over distances comparable with the size of the entire embryo. The assumption concerning the percolation mechanism of cell death is used as a basis for estimating the statistical average value of cell connectedness at which the predicted number of cells theoretically isolated from the flow of signal molecules corresponds to the observed frequencies of dying embryonic cells. The estimated average number of cell interactions significantly exceeds the threshold of information resource percolation in the embryonic space and agrees with estimations of other authors, based on direct observations. The probable role of the diffusion front, or percolation cluster shell, in the regionalization of embryonic structures differing in their prospective values is discussed. It is shown that the duration of the communicative period, along with the statistical average number of channels providing for the intercellular transfer of signal molecules by diffusion, is a parameter controlling the processes of determination of embryonic structures.     

Central root cap cells are depleted of endoplasmic microtubules and actin microfilament bundles: implications for their role as gravity-sensing statocytes

Summary Indirect immunofluorescence, using monoclonal antibodies to actin and tubulin, applied to sections of root tips ofLepidium, Lycopersicon, Phleum, andZea, revealed features of the cytoskeleton that were unique to the statocytes of their root caps. Although the cortical microtubules (CMTs) lay in dense arrays against the periphery of the statocytes, these same cells showed depleted complements of endoplasmic microtubules (EMTs) and of actin microfilament (AMF) bundles, both of which are characteristic of the cytoskeleton of other post-mitotic cells in the proximal portion of the root apex. The scarcity of the usual cytoskeletal components within the statocytes is considered responsible for the exclusion of the larger organelles (e.g., nucleus, plastids, ER elements) from the interior of the cell and for the absence of cytoplasmic streaming. Furthermore, the depletion of dense EMT networks and AMF bundles in statocyte cytoplasm is suggested as being closely related to the elevated cytoplasmic calcium content of these cells which, in turn, may also favour the formation of the large sedimentable amyloplasts by not permitting plastid divisions. These latter organelles are proposed to act as statoliths due to their dynamic interactions with very fine and highly unstable AMFs which enmesh the statoliths and merge into peripheral AMFs-CMTs-ER-plasma membrane complexes. Rather indirect evidence for these interactions was provided by showing enhanced rates of statolith sedimentation after chemically-induced disintegration of CMTs. All these unique properties of the root cap statocytes are supposed to effectively enhance the gravity-perceptive function of these highly specialized cells.Dedicated to Prof. Dr. Benno Parthier on the occasion of his retirement     

Comparison of mineral contents between the arteries in upper and lower limbs of japanese monkeys

To examine whether the calcium accumulation in aged arteries is related to the way of walking, the mineral contents were determined in the arteries of Japanese monkeys of quadrupedal walk by inductively coupled plasma-atomic emission spectrometry. Sixteen Japanese monkeys consisting of 7 males and 9 females ranging in age from 2 to 33 yr were studied. The accumulation of calcium, phosphorus, and magnesium occurred progressively in most, but not all, of the arteries with aging. It was found that independent of the upper and lower limbs, a higher accumulation of calcium, phosphorus, and magnesium occurred in the arteries of the proximal regions with aging, compared with the arteries of the distal regions. In a comparison between the arteries of anatomically corresponding regions of the upper and lower limbs, the accumulation of calcium and magnesium was 20–60% higher in the external iliac and femoral arteries of the lower limb than in the axillary and brachial arteries of the upper limb. Regarding phosphorus, the accumulation was 20–120% higher in the external iliac and femoral arteries than in the axillary and brachial arteries. It was known that in humans, the accumulation of calcium, phosphorus, and magnesium was three to seven times higher in the arteries of the lower limb than in the arteries of the upper limb. It is clear that there is a very significant difference in the accumulation of calcium and magnesium in the arteries of the lower limbs between Japanese monkeys and humans. The present study suggests that the accumulation of calcium and magnesium in the arteries of the lower limb with aging is affected by the way of walking.     

The structure and function of the scutellum of the Grarnineae

NEGBI, M., 1984. The structure and function of the scutellum of the Gramineae. Four kinds of scutella, of which only the first is universally known, can be distinguished in the Gramineae. (1) The scutellum sew stricto , the kind most commonly described in textbooks. In this scutellum the only growth activity during germination is the development of every epithelial cell into a separate elongated papilla. These papillae are involved in secretion of hydrolases, gibberellins and other hormonal factors which in their turn activate the aleurone layer; and in absorption of the mobilized endosperm reserves. (2) The kind characteristic of Auma is found in several genera. In this the scutellar tip elongates during germination, reaches the distal end of the endosperm sac and develops papillae over its whole surface. (3) The kind found in Cizuniu in which the scutellar tip elongates and extends to the far end of the caryopsis during embryo development, but not during germination. In this scutellum only the abaxial surface faces the bulk of the storage endosperm and probably only this surface becomes papillate. Several bamboo genera have the kind of scutellum characterized by Melocannu . This scutellum has evolved as a storage organ and in mature caryopses the endosperm is reduced. This kind is associated with vivipary and with the presence of storage tissue in the pericarp.
The vascularization and the structure of the scutellar epithelium, as studied mainly in a limited number of species belonging to the first kind, are related to the functions of the scutellum. The scutellum has a prime role in controlling the mobilization of endosperm reserves.     

Migration and differentiation of gonadotropin-releasing hormone-producing neurons in the brain of mouse fetus exposed to excess of serotonin

The work has been carried out on mice of the Tg8 line with knockout of gene of monoamineoxidase A with an increase of serotonin and noradrenaline content in the brain, and on mice of the C3H line with unchanged genome and normal concentration of monoamines. An immunocytochemical study has been performed of development of neurons producing gonadotropin-releasing hormone (GnRH) under conditions of excess of serotonin and noradrenaline in the mice in embryogenesis. The GnRH-neurons were revealed at the 18th day of embryonic development in telencephalon along trajectory of their migration from olfactory bulbs to the retrochiasmatic area. In telencephalon of mouse embryos of the Tg8 line, a redistribution of the GnRH-neurons along their migration trajectory was observed as compared with embryos of the C3H line mice. The percent of the GnRH-neurons in the Tg8 mouse embryos in caudal parts of the migration trajectory was lower than in rostral parts, the opposite distribution of the neurons being observed in the C3H line mouse embryos; at the excess of serotonin and noradrenaline in the Tg8 line mouse embryos, the total amount of GnRH-neurons in the brain was lower than in the C3H mice. In males of the Tg8 line mice under conditions of excess of serotonin and noradrenaline the optical density of neurons, which correlated with the GnRH concentration in the cell, was higher than in control mice. Thus, in the Tg8 mice under conditions of the serotonin and noradrenaline excess, migration of the GnRH-neurons to their final anlage in hypothalamus is accelerated as well as the total number of the GnRH-neurons decreases, which indicates a decrease of proliferation of cells-precursors and the earlier differentiation of neurons.     

Échinodermes de l'Ordovicien supérieur (Ashgill) de Sardaigne et d'Algérie

Research on the influence of sea level variations on the benthic faunas have been carried out in the Upper Ordovician of Sardinia. Study of the depositional facies and sequence analysis of the upper part (Lower Ashgill) of the Portixeddu Formation led to the identification of the sedimentary environments. Cystoids and crinoids are associated to bryozoans and brachiopods in most levels. The numerical analysis of associations and megaguilds shows that crinoids and cystoids have a higher frequency in the proximal and median facies of the upper offshore. The columnal association characterized by Conspectocrinus celticus and the coronoid Mespilocystites tregarvanicus has been discovered in the upper part of the formation. This material and complementary samples from Upper Ordovician of Sardinia and Kabylia (Algeria) bring additional data on the systematic and show the wide distribution of this fauna outside of the Ibero-armorican domain. The distribution of this echinoderm association supports a palaeogeographical position of the Ibero-armorican domain and Sardinia within the north gondwanan margin during the Lower Palaeozoic.     

Analysis of Foraging Behaviour of the Whitefly Parasitoid Encarsia formosa on a plant: A Simulation Study

The foraging behaviour of Encarsia formosa was analyzed using a stochastic simulation model of the parasitoid's behaviour. Parasitoids were allowed to search during a day on a tomato plant infested with immatures of the greenhouse whitefly, Trialeurodes vaporariorum. The model simulates searching, host selection, host handling and patch leaving behaviour, and the physiological state of the parasitoid. The outputs of the model are the number of visited leaflets and the number of hosts encountered, parasitized or killed by host feeding. The simulation results agreed well with observations of parasitoids foraging on tomato plants. The number of encounters and ovipositions on the plant increased with host density according to a type II functional response. At a clustered host distribution over leaflets and low host densities, the most important parameters affecting the number of ovipositions were the leaf area, the parasitoid's walking speed and walking activity, the probability of oviposition after encountering a host, the initial egg load and the ratio of search times on both leaf sides. At high densities, the maximum egg load and the giving-up time on a leaflet since latest host encounter were the most essential parameters.     

Le peuplement humain en Eurasie : l’Asie centrale montagneuse et les piémonts sous-himalayens du Plio-Pléistocène à l’Holocène, origines, évolution humaine et migrations

During the years 1996 and 1997, a team of the Laboratory of Prehistory, National Museum of Natural History, Paris, and of the Departments of Archaeology, Karachi and Peshawar University, Pakistan, leads the first prehistoric field investigation in the District of Chitral, Hindu Kush, close to the Wakhan Corridor (the Amu Daria course in the Pamir). Problematics are the origins and the becoming of the Epipaleolithic/Neolithic hunters-gatherers known in the Pamir Plateau and the Gissar Range, the lithics tradition of which share common roots with the Sub-Himalayan Soanian tradition (Mode 1). A second field investigation has been conduced in the North West India, where Soan developed from Early Pleistocene, in the Frontal Range of the Siwaliks and Himachal Pradesh during the years 2003, 2005 and 2006 in cooperation with the Department of Archaeology and Museums of Punjab, India. New discoveries in both countries support new hypothesis for the understanding of human evolution in Asia and Homo sapiens origins.     

Schistosoma manonsi: cercarial penetration of host epidermis at the ultrastructural level

Invasion of the outer layers of the epidermis of mouse ear skin by cercariae of Schistosoma mansoni within 7 min of their application to it has been studied with the optical and the scanning and transmission electron microscopes.Entrance of cercariae was under the edges of the dead flattened keratinized cells of the horny layer (squames), and penetration through this layer was by disarticulation of the stacks of squames at their interdigitations. Mucus from the postacetabular glands was recognized with the light and electron microscopes on the skin surface, especially at squame edges and between layers of squames and along the keratogenous zone. The findings suggested that disarticulation of the squames was not effected solely by the muscular probing and pushing of the parasite, but that it might be aided by swelling of the mucus secretion deposited in the area from the postacetabular glands. Loosening of the interlocked edges of the squames by enzymatic action is also a possibility, but was not evaluated for this report.The migration path along the keratongenous zone was marked by extensive damage to the transitional cells of the granular layer subjacent to the squames. Packets of secretion from the cercarial preacetabular glands were identified below the horny layer in the cytoplasm of these cells. It was considered that the host tissue damage in this area was the result not only of tearing of the tissues by passage of the spiny schistosomules, but also of enzymatic activity, the enzyme source being the granules in the packets of preacetabular gland secretion.     

L’étude des conditions d’habitabilité des établissements préhistoriques : à propos des amas coquilliers mésolithiques de la région cantabrique occidentale (Nord de l’Espagne)

We show the methodology we followed in order to reliably estimate a factor that, to our judgement, is fundamental for the assessment of the characteristics of a prehistoric settlement: the conditions of exposure to the sun. This methodology is applied to the study of Mesolithic shell middens in the North of Spain, with the aim to introduce a new kind of information in the debate about the meaning of shell middens. Throughout this century, different ways to understand the behaviour these remains conceal have been proposed. Our thesis with regard to it, presented in this paper, is based on the observation of a series of variables, among which we can find the exposure to the sun the settlements undergo. We therefore show in the last part of the paper, how to join the information from the proposed analysis with the other data subsequent from the study of other variables such as the environmental conditions prevailing during the period of formation of the sites; the situation of the settlements; the location of the remains in the caves; the entity of the occupations; and the energy spent on the transportation of the aquatic resources from the coast towards the places where their rests are found nowadays. In short, we propound a methodology for the study of one of the variables that falls upon the habitability of a prehistoric settlement and we point out the contribution that the incorporation of an analysis of this kind means for the research of Mesolithic shell middens in the North of Spain.     

Theoretical model of reticulocyte to erythrocyte shape transformation

A theoretical model describing the kinetics of reticulocyte shape transformation was developed. The model considers the evolution of a simple cellular shape under transmembrane pressure difference, and proposes a four-parameter axisymmetric approximation of the cell surface. The mathematical analysis considers plasma membrane tension in the plane of bilayer leaflets, membrane spontaneous curvature and transmembrane transport of water. Cytoskeleton dilatational and shear rigidity, and the energetic barrier preventing the decrease of cell volume below a certain minimum are also incorporated. The set of adequate physical assumptions allowed for formulation of the equation for free energy of the investigated system. Computer simulations of cell shape changes, down to the state of free energy minimum, together with estimation of the time needed for the resulting transport of water, revealed a complex, three-phase picture of temporal alterations in cellular geometry with a wide spectrum of final results, and led to propose a standard model of reticulocyte-erythrocyte transformation. According to the model, both cell volume and surface undergo changes, and the work of the pressure, initially accumulated in the cytoskeleton, is consumed for local bending of the cell membrane. Further simulations with modified initial shape or parameters of the standard model show the trajectories of system evolution and help in better understanding the conditions for the erythro-, sphero-, ovalo-, stomato-, and leptoidal metamorphosis of maturing red blood cells. The stability of the final biconcave shape was also verified. Spherogenic modifications were discussed in the context of spherocytosis. Future development of the model was proposed.     

A view from the forest floor: the impact of logging on indigenous peoples in Brazil

The social impact of the mahogany trade on the indigenous peoples of Brazil is described. Emphasis is placed on the violence directed against Indians and the consequences of the destruction of their environment which results from the trade. Also mentioned are the judicial issues regarding the illegal extraction of mahogany from protected areas and several of the court cases against logging companies. A moratorium on mahogany logging in Brazil is advocated as is the right of indigenous peoples to control their lands and resources as the way to conserve their environment.     

Evolution of pupation site and interspecific competitive ability in Drosophila hydei

A competition experiment conducted over a period of 50 weeks resulted in stable coexistence of Drosophila hydei and D. melanogaster. In a repeat of this experiment the results for the first 25 weeks were similar to the results of the earlier experiment, but after this time the state of coexistence collapsed and a fairly rapid trend towards competitive exclusion was observed. Extinctions of D. melanogaster occurred in 11 of the 12 experimental cages before termination of the experiment at 50 weeks. At about the same time as the competitive ability of D. hydei increased, an alteration in the range of pupation sites utilized by this species was noted. The change in pupation site was demonstrated to be at least partially heritable, and it appears to be responsible for D. hydei's increased competitive ability. This experiment provides an example of natural selection within a competing population acting against the stability of the overall two-species system.