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Background: Passiflora setacea (PS) is a passionfruit variety of the Brazilian savannah and is a rich source of plant food bioactives with potential anti-inflammatory activity. This study aimed to investigate the effect of an acute intake of PS juice upon inflammation, metabolic parameters, and gene expression on circulating immune cells in humans. Methods: Overweight male volunteers (n = 12) were enrolled in two double-blind placebo-controlled studies. Blood samples were collected from fasting volunteers 3 h after the consumption of 250 mL of PS juice or placebo (PB). Metabolic parameters (insulin, glucose, total cholesterol, high-density lipoprotein (LDL), high-density lipoprotein (HDL), and total triglycerides) and circulating cytokines were evaluated (study 1). Peripheral blood mononuclear cell (PBMC) from the same subjects were isolated and RNA was extracted for transcriptomic analyses using microarrays (study 2). Results: Insulin and homeostatic model assessment for insulin resistance (HOMA-IR) levels decreased statistically after the PS juice intake, whereas HDL level increased significantly. Interleukin (IL)-17A level increased after placebo consumption, whereas its level remained unchanged after PS juice consumption. Nutrigenomic analyses revealed 1327 differentially expressed genes after PS consumption, with modulated genes involved in processes such as inflammation, cell adhesion, or cytokine&ndash, cytokine receptor. Conclusion: Taken together, these clinical results support the hypothesis that PS consumption may help the prevention of cardiometabolic diseases.

The 4‰ initiative launched by the French government at COP21 in Paris in December 2015 aspires to increase global soil organic carbon (SOC) stocks at a rate of 0.4% per year. We conducted a systematic literature review on SOC storage under agroforestry and conservation agriculture systems in sub-Saharan Africa, where we reported 66 and 33 cases for both systems respectively. The results showed that SOC storage rates were significantly higher than 4‰ yr−1 in fallows and in multistrata agroforestry systems (P = 0.0001 and 0.0178, respectively), but not in alley cropping and parklands systems. For conservation agriculture, SOC storage rates were only significantly higher than 4‰ yr−1 (P = 0.0438) when all three principles were applied, i.e. no- or minimum tillage combined with crop residue retention and intercropping or rotation. The data showed very large variability in SOC storage rates as the result of various factors, including previous land-use history, experimental set up and approach used to determine SOC storage (diachronic versus synchronic approach), soil type, depth of soil sampling, type of crops and management, and duration of the experiment. SOC storage rates significantly decreased with time in the agroforestry systems (P = 0.0328). However, we were unable to find significant relationships with initial SOC stocks or tree density. Given the limited published data and the high variability in results, no significant relationships between SOC storage rates and site variables were found for conservation agriculture. We argue that there is a potential for SOC storage in agricultural soils of sub-Saharan Africa, as illustrated by SOC gaps observed on smallholder farms. Low SOC levels are, however, to a great extent the result of limited resources of most smallholder farmers. Practices such as agroforestry and conservation agriculture can restore SOC in these soils, but the 4‰ initiative has to be implemented on the grounds of the positive impact on crop productivity rather than on climate change mitigation. The efficiency in doing so will depend on the specific situations and will need economic support to smallholder farmers, including the promotion of good markets for sale of extra produce and for input supply, effective private support and policy, such as credit schemes and subsidies for inputs, and efficient extension services which incentivize farmers to invest in new technologies.

International audience; In working with soil physics, getting new answers to the same questions is a challenge. As soil physicists, we are always hoping to find new ways of understanding such a complex soil science area. In this chapter, we will discuss some of the ways to assess soil physical quality for crop growth, using ascending complexity classification, from the simplest to the more complex soil physical indicators for crop growth.

Five strains, JPY461T, JPY359, JPY389, DPU-3 and STM4206 were isolated from nitrogen-fixing nodules on the roots of Mimosa spp. and their taxonomic positions were investigated using a polyphasic approach. All five strains grew at 15–40 °C (optimum, 30–37 °C), at pH 4.0–8.0 (optimum, pH 6.0–7.0) and with 0–1 % (w/v) NaCl [optimum, 0 % (w/v)]. On the basis of 16S rRNA gene sequence analysis, a representative strain (JPY461T) showed 97.2 % sequence similarity to the closest related species Burkholderia acidipaludis SA33T, a similarity of 97.2 % to Burkholderia terrae KMY02T, 97.1 % to Burkholderia phymatum STM815T and 97.1 % to Burkholderia hospita LMG 20598T. The predominant fatty acids of the five novel strains were summed feature 2 (comprising C16 : 1 iso I and/or C14 : 0 3-OH), summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c), C16 : 0 , C16 : 0 3-OH, C17 : 0 cyclo, C18 : 1 ω7c and C19 : 0 cyclo ω8c. The major isoprenoid quinone was Q-8 and the DNA G+C content of the strains was 63.0–65.0 mol%. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminophospholipid, an unidentified aminolipid and several unidentified phospholipids. The DNA–DNA relatedness of the novel strain with respect to recognized species of the genus Burkholderia was less than 54 %. On the basis of 16S rRNA and recA gene sequence similarities, chemotaxonomic and phenotypic data, the five strains represent a novel species in the genus Burkholderia , for which the name Burkholderia diazotrophica sp. nov. is proposed with the type strain, JPY461T ( = LMG 26031T = BCRC 80259T = KCTC 23308T).

C. R. Geosci. ISI Document Delivery No.: 761BF Times Cited: 2 Cited Reference Count: 30 Santos, Glenio Guimaraes da Silva, Euzebio Medrado Marchao, Robelio Leandro da Silveira, Pedro Marques Bruand, Ary James, Francois Becquer, Thierry CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brazil); Embrapa Cerrados-IRD [0203205] This research is part of the project Embrapa Cerrados-IRD, No. 0203205 (Mapping of the Biome Cerrado Landscape and Functioning of Representative Soils). This work was supported by a grant awarded to G.G. Santos by the CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brazil) Elsevier france-editions scientifiques medicales elsevier Paris; International audience; Among the various soil indicators established in order to discuss physical properties of soils is the S-index, derived from the slope of the soil water retention curve at its inflection point, used by a number of authors. In this publication we discuss the value of the slope at the inflection point of the soil water retention curve according to the independent variable used to plot it. We show that a representation of the water content according to the arithmetic rather than logarithmic expression of the suction for the S-index yields a different result for the soil selected. More generally, our results show that examining the physical properties of soil using a water retention curve plotted with an arithmetic expression of suction offers greater potential than when plotted with its natural or decimal logarithm as is often found in the literature. Parmi les différents indicateurs qui ont été proposés pour rendre compte des propriétés physiques du sol, l'indice S, qui correspond à la pente de la courbe de rétention en eau du sol à son point d'inflexion, a été largement utilisé. Dans cet article, nous discutons de la valeur de la pente au point d'inflexion de la courbe de rétention en eau du sol, en fonction de la variable indépendante qui est utilisée pour le déterminer. Nous montrons que la représentation de la teneur en eau en fonction de l'expression arithmétique de la succion au lieu de son expression logarithme, comme pour l'indice S, conduit à un résultat différent pour le sol sélectionné. Plus généralement, nos résultats montrent qu'une discussion des propriétés physiques du sol, en utilisant une représentation de la courbe de rétention d'eau en fonction de l'expression arithmétique de la succion, offre plus de possibilités que l'expression logarithmique naturelle ou décimale qui a été largement utilisée jusqu'alors.

International audience; Brazilian Latosols are characterized by low activity clay, little horizon differentiation, a weak macrostructure and a strong microgranular structure. The development of the latter that was reported as being possibly related to the fine material mineralogy, location in the landscape, parental material and biological activity is still under discussion. The aim of this study is to discuss the origin of the microgranular structure of Latosols located in the Brazilian Central Plateau. Ten Latosols (L) developed in different parent materials were selected along an approximately 350-km long regional toposequence across the South American Surface (SAS) (L1 to L4) and Velhas Surface (VS) (L5 to L10). The structure of the Latosols was studied in the field and samples of the diagnostic Bw horizons were collected for laboratory analyses. Basic soil characterization was performed on the

International audience; This study aims at comparing the centrifuge and pressure plate methods when appropriate duration of run is adopted. Samples collected in tropical soils located in Brazil along a 10-km local hydrosequence across the Cerrado-Amazonia transition (set 1) and along a 350-km regional toposequence across the Cerrado region (set 2) were selected to compare and discuss statistically the similarity of the soil-water retention recorded by using the pressure plate and centrifuge methods. The results showed good agreement (R2 = 0.99) for the 1:1 comparison of measured point-wise soil-water content values (set 1) as well as for the fitted soil-water content curves by van Genuchten model using data points obtained with the two methods (set 2). Thus, the centrifuge method should be considered as an appropriate method for determining soil-water retention properties not only for the similar results with the pressure plate method but also for being much less time consuming.

International audience; The mineralogy of the Latosols of the Brazilian Central Plateau remains under discussion in the absence of a clear relationship with their age according to their geomorphic location. The aim of this study was thus to clarify the origin of the kaolinite and gibbsite content variation by studying a regional toposequence and using data from the literature. Chemical composition and soil color were used to discuss mineralogy. The mineralogy of the clay fraction was also investigated using X-ray diagrams. Our results showed that the large variation of kaolinite and gibbsite content can be explained by taking into account both their local and regional location, the variation of the hematite and goethite content remaining limited. The model that is proposed to explain such variation combines a regional component, which is mainly associated to the age of the geomorphic surface and a local component which is mainly associated to the hydraulic conditions along the toposequence. La minéralogie des latosols du Plateau Central brésilien est discutée en l'absence de relation clairement établie avec leur âge qui est en fonction de leur position géomorphologique. L'objectif de cette étude est par conséquent de clarifier l'origine de la variation de teneur en kaolinite et gibbsite en étudiant une toposéquence régionale et les données de la littérature. La minéralogie a été discutée à partir de la composition chimique et de la couleur du sol. Elle a aussi été discutée à l'aide des données de la diffraction des rayons X. Les résultats montrent que la variation élevée de la proportion de kaolinite et de gibbsite des latosols peut être expliquée en prenant en compte à la fois leur localisation régionale et locale. Le modèle proposé combine en effet une composante régionale qui est principalement liée à l'âge de la surface géomorphologique et une composante locale qui est principalement liée aux conditions hydriques le long de la toposéquence.

International audience; The Brazilian Central Plateau is constituted of the South American Surface and Velhas Surface geomorphologic surfaces and represents 24% of the Brazilian territory. Latosols cover about 40% of these Surfaces. Kaolinite, gibbsite, goethite and hematite were recognized in different proportions in the clay fraction of Latosols by many authors. The objective of this work was to analyse the kaolinite cristalinity and to discuss its variability according to the Latosol location on the geomorphic Surfaces of the Brazilian Central Plateau.

International audience; The Brazilian Central Plateau Latosols occurs on Tertiary South American and Velhas planning surfaces. The purpose of this work was to determine activation energy of kaolinite dehydroxylation and its genesis relationships of the Brazilian Central Plateau Latosols.

The Brazilian Central Plateau is constituted of the two main geomorphic surfaces: the South American surface and the Velhas surface. These surfaces were developed during the Cretaceous Superior and Tertiary and are covered by deeply weathered Latosols. The South American surface is the oldest and occupies the highest position in the landscape (950 to 1,200 m altitude) with smoothly convex plane portions. The Velhas surface is composed by irregular and slightly sloping planes and occupies in the landscape (750 to 950 m altitude). It is connected to the South American surface by areas of steep hillsides.

Latosols are deeply weathered soils characteristic of the moist tropics. Many Latosols have kaolinitic horizons overlying more gibbsitic ones (Lucas, 1989), for which there has been no satisfactory pedological explanation and why they have often been considered as a sedimentary succession. Several hypotheses to explain this phenomenon were expressed: biogeochemical recycling of Si by the forest (Lucas et al., 1993) or the activity of termites (Volland-Tuduri, 2005). The objective of this study is to model the development of Latosols of the Brazilian Central Plateau considering the respective effect of parent material, time or biological activity. This plateau is constituted of the two main geomorphic surfaces: the South American surface (Suface I) and the Velhas surface (Surface II). In the Central Plateau, the Latosols can be identified as Red Latosols (~28%), Yellow Red Latosols (~10%) and Yellow Latosols (~2%), (Reatto, 1998).

The Cerrados Biome is one of the major regions of Brazil with 24% of the Brazilian territory (204.106 ha). It is mainly located in the center of Brazil and corresponds to the whole Central Plateau. About 49% of the soils are Ferralsols and approximately 79.106 ha of these soils are dedicated to agriculture. The main characteristics of Ferralsols are a poor horizonation, a weak development of the macrostructure, and a strong submillimetric granular microstructure.

Ferralsols have a ferralic horizon at some depth between 30 and 200 cm that results from long and intense weathering. Their clay fraction is usually mainly low-activity clay consisting of kaolinite with hematite, goethite and gibbsite in different proportions. Ferralsols show little or no horizonation, and their macrostructure is absent to moderate. On the other hand, they have typically a strong microstructure consisting of microaggregates < 1 mm in size. Because of the lack or small development of macrostructure, porosity of Ferralsols is closely related to the development of microstructure and the assemblage of elementary particles within the microaggregates with a small contribution of large pores resulting from root development and macrofaunal activity. Their physical properties are then closely related to the development of this microstructure. However, there is still no model in the literature that predicts changes of microstructure of these soils using easily accessible soil properties when land-use is modified. The objective of this work was to relate microstructure development to the bulk density (Db) in Ferralsols and then to make possible the use of Db as an indicator of microstructure development.

The physical properties of Brazilian Oxisols are closely related to the development of their microstructure, which typically consists of stable microaggregates >1 mm. There is no model available to predict changes in microstructure in Oxisols. The objective of this work was to relate the proportion of microaggregates to the bulk density (D b ) in the soil studied. Five sites of a typic Haplustox under native vegetation (two sites) and pasture (three sites) were sampled. Soil bulk density, sand, silt, and clay content and aggregate-size distribution were measured from the surface to 1.6 m deep in increments of 0.1 m. Thin sections were prepared from undisturbed samples collected in duplicate from 0- to 0.1-, 0.3- to 0.4-, 0.8- to 0.9-, and 1.5- to 1.6-m depths, and backscattered electron scanning images (BESI) were generated. Clay content ranged from 672 to 798 g kg - 1 and bulk density between 0.87 and 1.18 g cm among the 80 samples studied. Bulk density was poorly correlated with clay content (R 2 = 0.358) and at any depth was not significantly smaller under native vegetation than under pasture. Visual assessment of BESI revealed that soil material corresponded to either microaggregates (

Among microaggregated soils, there are Ferralsols that show little or no distinct horizonation. Their macrostructure is weak to moderate and they have typically a strong microstructure. In most Brazilian clayey Ferralsols, physical properties are closely related to the development of microstructure that consists of subrounded microaggregates 50 to 500 µm in diameter.