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31.
Jean-Jacques Godon Laure Arcemisbéhère Renaud Escudié Jérôme Harmand Edouard Miambi Jean-Philippe Steyer 《Bioenergy Research》2013,6(3):1063-1081
Over millions of years, living organisms have explored and optimized the digestion of a wide variety of substrates. Engineers who develop anaerobic digestion processes for waste treatment and energy production can learn much from this accumulated ‘experience’. The aim of this work is a survey based on the comparison of 190 digestive tracts (vertebrate and insect) considered as ‘reactors’ and their anaerobic processes. Within a digestive tract, each organ is modeled as a type of reactor (continuous stirred-tank, such reactors in series, plug-flow or batch) associated with chemical aspects such as pH or enzymes. Based on this analysis, each complete digestion process has been rebuilt and classified in accordance with basic structures which take into account the relative size of the different reactors. The results show that all animal digestive structures can be grouped within four basic types. Size and/or position in the structure of the different reactors (pre/post treatment and anaerobic microbial digestion) are closely correlated to the degradability of the feed (substrate). Major common features are: (i) grinding, (ii) an extreme pH compartment, and (iii) correlation between the size of the microbial compartment and the degradability of the feed. Thus, shared answers found by animals during their evolution can be a source of inspiration for engineers in designing optimal anaerobic processes. 相似文献
32.
Andrea Picin Marco Peresani Christophe Falguères Giulia Gruppioni Jean-Jacques Bahain 《PloS one》2013,8(10)
The introduction of Levallois technology in Europe marked the transition from the Lower to the early Middle Paleolithic. This new method of flake production was accompanied by significant behavioral changes in hominin populations. The emergence of this technological advance is considered homogeneous in the European archaeological record at the Marine isotopic stage (MIS) 9/MIS 8 boundary. In this paper we report a series of combined electron spin resonance/U-series dates on mammal bones and teeth recovered from the lower units of San Bernardino Cave (Italy) and the technological analyses of the lithic assemblages. The San Bernardino Cave has yielded the earliest evidence of Levallois production on the Italian Peninsula recovered to date. In addition to our results and the review of the archaeological record, we describe the chronological and geographical differences between European territories and diversities in terms of technological developments. The belated emergence of Levallois technology in Italy compared to western Europe corresponds to the late Italian Neanderthal speciation event. The new radiometric dates and the technological analyses of San Bernardino Cave raise the issue of the different roles of glacial refugia in the peopling and the spread of innovative flaking strategies in Europe during the late Middle Pleistocene. 相似文献
33.
Mustapha Faghire Farissi Mohamed Khadijattou Taoufiq Rachid Fghire Adnane Bargaz Btissam Mandri Khalid Oufdou Amenc Laury Jean-Jacques Drevon Cherki Ghoulam 《Symbiosis (Philadelphia, Pa.)》2013,60(3):115-122
The effect of salt stress, under glasshouse conditions, was studied on plant biomass, nodulation, and activities of acid phosphatases (APase, EC 3.1.3.2) and trehalose 6-phosphate phosphatase (TPP, EC 3.1.3.12) in the symbiosis common bean (Phaseolus vulgaris L.)-rhizobia nodules. Four common bean recombinant inbred lines (147, 115, 104 and 83) were separately inoculated, with CIAT 899 or RhM11 strains and grown in hydroaeroponic culture. Two NaCl levels (0 and 25 mM NaCl plant?1 week?1 corresponding, respectively, to the control and the salt treatment) were applied and the culture was assessed during 42 days after their transplantation. The results showed that the nodulation of these lines was not affected by salinity except for the line 83 inoculated with CIAT 899, whose nodule dry weight decreased by 48.24 % compared with the corresponding controls. For the other symbiotic combinations, shoot and root biomasses were not significantly affected by salt constraint. Salinity stress generally reduced acid phosphatise and trehalose phosphate phosphatase activities in nodules that were less affected in plants inoculated with RhM11. Based on our data, it appears that nodule phosphatase activity may be involved in salinity tolerance in common beans and the levels of salt tolerance depend principally on specific combination of the rhizobial strain and the host cultivar. 相似文献
34.
Sarah E. Freidline Philipp Gunz Katerina Harvati Jean-Jacques Hublin 《Journal of human evolution》2013
The fossil ATD6-69 from Atapuerca, Spain, dated to ca. 900 ka (thousands of years ago) has been suggested to mark the earliest appearance of modern human facial features. However, this specimen is a subadult and the interpretation of its morphology remains controversial, because it is unclear how developmental shape changes would affect the features that link ATD6-69 to modern humans. Here we analyze ATD6-69 in an evolutionary and developmental context. Our modern human sample comprises cross-sectional growth series from four populations. The fossil sample covers human specimens from the Pleistocene to the Upper Paleolithic, and includes several subadult Early Pleistocene humans and Neanderthals. We digitized landmarks and semilandmarks on surface and CT scans and analyzed the Procrustes shape coordinates using multivariate statistics. Ontogenetic allometric trajectories and developmental simulations were employed in order to identify growth patterns and to visualize potential adult shapes of ATD6-69. We show that facial differences between modern and archaic humans are not exclusively allometric. We find that while postnatal growth further accentuates the differences in facial features between Neanderthals and modern humans, those features that have been suggested to link ATD6-69's morphology to modern humans would not have been significantly altered in the course of subsequent development. In particular, the infraorbital depression on this specimen would have persisted into adulthood. However, many of the facial features that ATD6-69 shares with modern humans can be considered to be part of a generalized pattern of facial architecture. Our results present a complex picture regarding the polarity of facial features and demonstrate that some modern human-like facial morphology is intermittently present in Middle Pleistocene humans. We suggest that some of the facial features that characterize recent modern humans may have developed multiple times in human evolution. 相似文献
35.
Adnane Bargaz Mustapha Faghire Mohamed Farissi Jean-Jacques Drevon Cherki Ghoulam 《Acta Physiologiae Plantarum》2013,35(5):1633-1644
One of the most adverse effects of phosphorus (P) deficiency on N2-fixing legumes is the generation of harmful active oxygen species which cause oxidative stress. And although oxidative stress has been widely studied in roots and shoots of various plant species, it has not yet sufficiently been documented in bean nodules so far. In this study, two recombinant inbred lines RIL115 (P-deficiency tolerant) and RIL147 (P-deficiency sensitive) of common bean and Concesa (local variety) were inoculated separately with the reference strain R. tropici CIAT899, RhM11 (R. gallicum) or RhM14 (R. tropici); two local strains of the Marrakesh region of Morocco. Nodulated plants were grown under semi-hydroponic conditions with sufficient or deficient P supply and analyzed for their oxidative responses at the flowering stage. The results indicated that P-deficiency decreased the growth of shoots (48 %) and nodules (32 %), particularly with RhM14 exhibiting the highest decrease (52 %) of nodulation. This constraint increased electrolyte leakage of nodules (40 %) as compared to leaves (20 %), especially for plants inoculated with RhM14 and CIAT899. Moreover, high H2O2 and malondialdehyde contents were noticed in P-deficient nodules of RhM14 and RhM11. These variations were associated with peroxidase activity stimulation in P-deficient nodules induced by CIAT899 and RhM14. In symbiosis with RIL115, these last strains exhibited the highest nodule phenol content. Overall, phenol content was mainly enhanced in P-deficient nodules (35 %) as compared to the leaves (16 %). It was concluded that the genotypes inoculated with CIAT899 and RhM11 are relatively P-deficiency tolerant combinations as compared to those inoculated with RhM14. Increase of oxidative stress in nodules rather than in leaves points to the need for further investigations of mechanisms that improve the root-nodule efficiency under adverse conditions. 相似文献
36.
Jean-Jacques Candelier 《Cell Adhesion & Migration》2016,10(1-2):226-235
ABSTRACTThe hydatidiform mole (HM) is a placental pathology of androgenetic origin. Placental villi have an abnormal hyperproliferation event and hydropic degeneration. Three situations can be envisaged at its origin: 1. The destruction/expulsion of the female pronucleus at the time of fertilization by 1 or 2 spermatozoa with the former being followed by an endoreplication of the male pronucleus leading to a complete hydatidiform mole (CHM) 2. A triploid zygote (fertilization by 2 spermatozoa) leading to a partial hydatidiform mole (PHM) but can also lead to haploid and diploid clones. The diploid clone may produce a normal fetus while the haploid clone after endoreplication generates a CHM 3. A nutritional defect during the differentiation of the oocytes or the deterioration of the limited oxygen pressure during the first trimester of gestation may lead to the formation of a HM.In countries with poor medical health care system, moles (mainly the CHM) can become invasive or, in rare cases, lead to gestational choriocarcinomas. 相似文献
37.
38.
We describe two entelodontid upper premolars that were recovered from the late Eocene of the Krabi coal mine in southern Thailand. The size and morphology of the material suggest that it can be referred to Entelodon aff. E. gobiensis, a species known from the late Eocene to the early Oligocene of northern Asia and southern China. The Thai material documents for the first time the southernmost occurrence of entelodontids in Asia during the Paleogene and also suggests that Eocene Southeast Asian mammal localities might potentially yield further entelodontid remains mostly associated with selenodont ungulates. 相似文献
39.
Dugoua JJ Seely D Perri D Cooley K Forelli T Mills E Koren G 《Canadian journal of physiology and pharmacology》2007,85(9):837-847
Common (Cinnamomum verum, C. zeylanicum) and cassia (C. aromaticum) cinnamon have a long history of use as spices and flavouring agents. A number of pharmacological and clinical effects have been observed with their use. The objective of this study was to systematically review the scientific literature for preclinical and clinical evidence of safety, efficacy, and pharmacological activity of common and cassia cinnamon. Using the principles of evidence-based practice, we searched 9 electronic databases and compiled data according to the grade of evidence found. One pharmacological study on antioxidant activity and 7 clinical studies on various medical conditions were reported in the scientific literature including type 2 diabetes (3), Helicobacter pylori infection (1), activation of olfactory cortex of the brain (1), oral candidiasis in HIV (1), and chronic salmonellosis (1). Two of 3 randomized clinical trials on type 2 diabetes provided strong scientific evidence that cassia cinnamon demonstrates a therapeutic effect in reducing fasting blood glucose by 10.3%-29%; the third clinical trial did not observe this effect. Cassia cinnamon, however, did not have an effect at lowering glycosylated hemoglobin (HbA1c). One randomized clinical trial reported that cassia cinnamon lowered total cholesterol, low-density lipoprotein cholesterol, and triglycerides; the other 2 trials, however, did not observe this effect. There was good scientific evidence that a species of cinnamon was not effective at eradicating H. pylori infection. Common cinnamon showed weak to very weak evidence of efficacy in treating oral candidiasis in HIV patients and chronic salmonellosis. 相似文献
40.
We synthesized and evaluated by surface plasmon resonance 64 LNA/2'-O-methyl sequences corresponding to all possible combinations of such residues in a kissing aptamer loop complementary to the 6-nt loop of the TAR element of HIV-1. Three combinations of LNA/2'-O-methyl nucleoside analogues where one or two LNA units are located on the 3' side of the aptamer loop display an affinity for TAR below 1nM, i.e. one order of magnitude higher than the parent RNA aptamer. One of these combinations inhibits the TAR-dependent luciferase expression in a cell assay. 相似文献